【10-9】FEM9.311RulesfortheDesignofStorageandRetrievalMachinesStructuresS欧洲物料搬运协会.
美丽中国(双语)智慧树知到课后章节答案2023年下山东建筑大学
美丽中国（双语）智慧树知到课后章节答案2023年下山东建筑大学山东建筑大学第一章测试1.Now，there arises a more popular saying that Sanshan refers to three touristattractions, which are（）.答案:Yandang Mountains in Zhejiang Province;Mount Lu in JiangxiProvince;Mount Huang in Anhui Province2.Mount Tai is a mountain of historical and cultural significance located southof the city of Tai’an, Shandong province. （）答案:错3.Confucius once said “No mountains home and abroad could be compared toAnhui’s Huangshan Mountain. There is no desire for climbing othermountains after a visit to Mount Huangshan, the viewing (of other mountains) stops.”（）答案:错4.Who renamed Huangshan in 747 AD?（）答案:Emperor Xuanzong of Tang5.（）is one of the steepest and most challenging hiking paths of MountTai? （）答案:The 18 Bends6.Mount Tai is among the first group of National Parks of China.（）答案:对7.玉皇顶 is translated as Jade Emperor Peak.（）答案:对8.Since ancient times, north has been believed to be the holiest point since itwas the direction from which the sun would rise, leading it to be associated with birth and renewal.（）答案:错9.Huangshan is located within Huangshan city in the（）of AnhuiProvince. （）答案:south10.Welcoming-Guests Pine is thought to be more than 1500 years old. （）答案:对第二章测试1.“不到长城非好汉”可以翻译为“He who fails to reach the Great Wall is not atrue man.”。
MICHIGAN DEPARTMENT OF HISTORY, ARTS, AND LIBRARIES TECHNICAL STANDARDS
MICHIGAN DEPARTMENT OF HISTORY, ARTS, AND LIBRARIESTECHNICAL STANDARDSFOR CAPTURING DIGITAL IMAGES FROM PAPER OR MICROFILM(By authority conferred on the department of history, arts, and libraries by sections 2 and 4 of therecords reproduction act, 1992 PA 116, section 2 as amended by 2004 PA 572 and section 4 asadded by 2004 PA 574, MCL 24.402 and 24.404)Section 1. Applicability and intentSec. 1. These standards apply to the conversion of public records from paper or microfilm todigital images for the purpose of maintaining official records in a digital format. They do notapply to digital photography, digital publications, or convenience copies of records producedpurely for the purpose of informational distribution, such as web publications and e-mails ofpublications.Section 2. DefinitionsSec. 2. (1) As used in these standards, the following definitions apply:(a) “Act” means the records reproduction act, 1992 PA 116, MCL 24.401 et seq.(b) “Agency” means a governmental entity or a governmental official acting in his or her officialcapacity, including but not limited to a state officer, employee, department, bureau, center,division, board, commission, council, authority, or other independent or dependent subunit of theexecutive branch of state government; an agency, board, commission, or council in thelegislative branch of state government; the judiciary; and a county, city, village, intercounty,intercity, or regional governing body, council, school district, special district, or other municipalcorporation, or a board, department, commission, council, or other independent or dependentsubunit of a municipal corporation.(c) “Department” means the department of history, arts, and libraries.(d) “DPI” and “PPI” mean and refer to dots per inch and pixels per inch, respectively. The termsmay be used interchangeably.(e) “Lossless compression method” means a compression method by which data are compressedby efficient coding of the information in the image and where the reconstructed image containsthe same amount of information as the original data.(f) “Lossey compression” means a compression method by which data are compressed byefficient coding of the information in the image and where the reconstructed image is only anapproximation of the original data.(g) “Quality assurance” means the process by which the total product is examined to ensure thatthe quality criteria initially established in the pre-production test have been met.(h) “Quality control” means and consists of those steps that are incorporated into the productionprocess and are designed specifically to reduce error.(i) “Standards” means the technical standards adopted in this set of technical standards.(j) “State archives” means the state archives of Michigan.7/1/2005(k) “Tagged image file format” or “TIFF” is a standard image file format recommended by the American National Standards Institute, “ANSI”, and the Association of Image and Information Management, “AIIM”.(2) The definitions listed in section 1 of the act apply to these standards.Section 3. Archival recordsSec. 3. Issues that affect the permanent preservation of the records include but are not limited to organization, indexing, format, resolution, compression algorithm, and storage media. An agency with a question about the suitability of an electronic format or technique for archival storage may contact the state archives for information and technical assistance.Section 4. Agency responsibilitiesSec. 4. (1) An agency is responsible for managing its records and information. An agency shall implement appropriate policies, procedures, and business practices, in order to ensure that a digital recordkeeping system selected by the agency will protect the authenticity, reliability, integrity, and usability of the records contained in the system and will address a migration path to a new system which will provide complete protection for the full retention period of the records stored in the system.(2) If an independent contractor, a consultant, or some other party outside of government produces a reproduction of a record for an agency, the agency shall ensure that the party acts in compliance with these standards. An agency may ensure compliance through execution of a contract that contains adequate legal safeguards.Section 5. Compression method standardSec. 5. (1) Compression methods may be used to reduce the amount of data needed to store or transmit a representation of a specific image.(2) If an agency uses a compression method to compress data, the lossless compression method T-4 (formerly known as group III) or the lossless compression method T-6 (formerly known as group IV), developed by the International Telecommunication Union - Telecommunication Standardization Sector, “ITU-T”, shall be used.(3) Lossy compression may be justified only when the retention value of the records is short term or when it is determined through testing that the desired results of the capture process cannot meet the agency’s business needs using a recommended format with lossless compression.(4) The selection of a compression scheme is application specific. The characteristics of the record, the tasks the system is designed to perform, and the user requirements to be satisfied shall be taken into account when selecting a compression scheme.Section 6. File format standardSec. 6. (1) A file format with lossless compression shall be used, so long as the format has the capability of conversion of its images to TIFF without a significant loss of information.(2) The use of a file format with lossy compression may be justified, when the retention life of a record is short term or if the agency determines through testing that the desired results of the capture process cannot meet the agency’s business needs using a recommended format with lossless compression.Section 7. Resolution standardSec. 7. (1) The minimum resolution level for standard business documents is 200 DPI/PPI. The minimum resolution level for line art, including but not limited to engineering drawings, and for those records intended for optical character recognition processing, is 300 DPI/PPI. For records that are designated to be transferred to the state archives in digital form, an agency may use higher resolution. The agency may contact the state archives to ascertain the appropriate resolution for records identified for permanent preservation or for transfer to the state archives. (2) The use of a lower resolution level may be justified when it is determined through testing that the desired results of the capture process cannot meet the agency’s business needs using a recommended format with a higher resolution level. Images shall exhibit a degree of legibility and readability comparable to the source document.Section 8. Enhancement technique standardSec. 8. An agency may employ a digitized record enhancement technique which is commonly used in scanning software, including but not limited to deskew, despeckle, crop, and rotate. An agency may not use an enhancement technique which alters content that exists in an original record.Section 9. Document preparation standardSec. 9. An agency shall engage in document preparation prior to scanning a record, a record series, or a collection of records.Section 10. Indexing standardSec. 10. (1) An agency may use any functional method to index digitized records, if the method adequately addresses all characteristics of the stored images, the requirements of the storage system, and end-user retrieval requirements.(2) Acceptable indexes include but are not limited to databases, spreadsheets, full-text optical character recognition systems, document profiles, and file naming conventions.Section 11. Quality control standardSec. 11. (1) An agency shall assemble a sample set of source documents or records equivalent in characteristics to the source documents, for the purposes of evaluating scanner results against defined quality criteria prior to production.(2) An agency shall establish quality control criteria based upon the results of the pre-production quality sample. The production process shall take account of the quality control criteria.(3) An agency shall produce a new sample for quality if the conditions or attributes of documents to be digitized change or if the equipment used to scan the documents change.Section 12. Quality assurance standardSec. 12. (1) An agency shall adopt written quality assurance procedures for inspection of digital images that are produced.(2) Quality assurance shall be conducted before the original documents are destroyed.(3) For more information regarding quality assurance an agency may refer to ANSI/AIIM TR34-1996 - Sampling Procedures for Inspection by Attributes of Images in Electronic Image Management (EIM) and Micrographics Systems.Section 13. Scanners and scanning standardSec. 13. (1) Except for regular computer enhancement routines used to improve the legibility of a scanned record, an agency shall not use an imaging system that is capable of altering a public record as scanned. Recorded text or characters in original records shall not be edited.(2) An agency shall periodically evaluate scanner quality. For more information on performing scanner quality evaluations, an agency may refer to ANSI/AIIM MS44-1998 (R1993) - Recommended Practice for Quality Control of Image Scanners.Section 14. Media standardSec. 14. An agency may use any media suitable for the storage of digital images as identified in the act, if the images are managed in a system which has an appropriate level of certainty for the recovery and security of the images and related index attributes.APPENDIX AREFERENCESNATIONAL STANDARDS AND RECOMMENDED PRACTICESThe following national standards and recommended practices issued by the American National Standards Institute (ANSI), the Association for Information and Image Management (AIIM), and the International Association for Standards (ISO) may contain additional information that will assist state agencies and local governments with complying with Michigan law. These publications are available from the Association for Information and Image Management, 1100 Wayne Ave., Suite 1100, Silver Spring, MD 20910-5699, /.ANSI/AIIM MS44-1998 (R1993) - Recommended Practice for Quality Control of Image ScannersANSI/AIIM MS50-1994 - Recommended Practice for Monitoring Image Quality of Aperture Card Film Image ScannersANSI/AIIM MS52-1991 - Recommended Practice for the Requirements and Characteristics of Original Documents Intended for Optical ScanningANSI/AIIM MS53-1993 - Recommended Practice; File Format for Storage and Exchange of Image; Bi-Level Image File Format: Part 1 MS 53-1993.pdfANSI/AIIM MS55-1994 - Recommended Practice for the Identification and Indexing of Page Components (Zones) for Automated Processing in an Electronic Image Management (EIM) EnvironmentANSI/AIIM MS58-1996 - Standard Recommended Practice for Implementation of Small Computer Systems Interface (SCSI-2) (X3.131-1994)ANSI/AIIM MS59-1996 - Media Error Monitoring and Reporting Techniques for Verification of Stored Data on Optical Digital Data DisksANSI/AIIM MS60-1996 - Electronic Folder Interchange DatastreamANSI/AIIM MS61-1996 - Application Programming Interface (API) for Scanners in Document Imaging SystemsANSI/AIIM TR1-1988 (A1992) - Guidelines for MetricsANSI/AIIM TR2-1998 - Glossary of Document TechnologiesANSI/AIIM TR15-1997 - Planning Considerations, Addressing Preparation of Documents for Image CaptureANSI/AIIM TR17-1989 - Facsimile and Its Role in Electronic ImagingANSI/AIIM TR19-1993 - Electronic Imaging Display DevicesANSI/AIIM TR21-1991 - Recommendations for the Identifying Information to be Placed on Write-Once-Read-Many (WORM) and Rewritable Optical Disk (OD) Cartridge Label(s) and Optical Disk Cartridge Packaging (Shipping Containers)ANSI/AIIM TR25-1995 - The Use of Optical Disks for Public RecordsANSI/AIIM TR26-1993 - Resolution as it Relates to Photographic and Electronic ImagingANSI/AIIM TR27-1996 - Electronic Imaging Request for Proposal (RFP) GuidelinesANSI/AIIM TR28-1991 - The Expungement of Information Recorded on Optical Write-Once-Read-Many (WORM) SystemsANSI/AIIM TR29-1993 - Electronic Imaging Output PrintersANSI/AIIM TR31:1-1992 - Performance Guideline for the Legal Acceptance of Records Produced by Information Technology Systems Part 1: EvidenceANSI/AIIM TR31:2-1993 -Performance Guideline for the Legal Acceptance of Records Produced by Information Technology Systems Part 2: Acceptance by Government AgenciesANSI/AIIM TR31:3-1994 - Performance Guideline for the Legal Acceptance of Records Produced by Information Technology Systems Part 3: ImplementationANSI/AIIM TR31:4-1994 - Performance Guideline for the Legal Acceptance of Records Produced by Information Technology Systems Part 4: Model Act and RuleANSI/AIIM TR32-1994 - Paper Forms Design Optimization for Electronic Image Management (EIM)ANSI/AIIM TR33-1998 - Selecting an Appropriate Image Compression Method to Match User RequirementsANSI/AIIM TR34-1996 - Sampling Procedures for Inspection by Attributes of Images in Electronic Image Management (EIM) and Micrographics SystemsANSI/AIIM TR35-1995 - Human and Organizational Issues for Successful EIM System ImplementationANSI/AIIM TR38-1996 - Compilation of Test Target for Document Imaging SystemsANSI/AIIM TR39-1996 - Guidelines for the Use of Media Error Monitoring and Reporting Techniques for the Verification of Information Stored on Optical Digital Data DisksANSI/AIIM TR40-1995 - Suggested Index Fields for Documents in Electronic Image (EIM) EnvironmentsISO 12653-1:2000 - Electronic Imaging - Test target for the black-and-white scanning of office documents - Part 1 - CharacteristicsISO 12653-2:2000 - Electronic Imaging - Test target for the black-and-white scanning of office documents - Part 2 - Method of useISO 15489-1:2001 - Information and Documentation - Records Management - Part 1 - General ISO 15489-2:2001 - Information and Documentation - Records Management - Part 2 - GuidelinesISO/TR 15801:2004 - Electronic Imaging - Information stored electronically - Recommendations for trustworthiness and reliability。
Calculus Rules of Dierentiation
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Rule 1: The Derivative of a Constant. The derivative of a constant is zero.
Rule 2: The General Power Rule. The derivative of xn is nxn−1.
Example 1 Differentiate y = x4.
The basic rules of differentiation are presented here along with several examples.
Remember that if y = f (x) is a function then the derivative of y can be represented
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国际象棋俱乐部规则英语作文
国际象棋俱乐部规则英语作文Rules and Regulations of the International Chess Club.I. Introduction.The International Chess Club is a prestigious organization dedicated to the promotion and development of the game of chess. Founded with the aim of fostering a competitive yet inclusive environment for chess enthusiasts, the club strives to provide a platform for players of all levels to improve their skills, engage in friendly matches, and share their passion for the game. These rules and regulations are designed to ensure the smooth operation of the club, fair play among members, and the maintenance of a respectful and enjoyable atmosphere.II. Membership.2.1 Eligibility.Membership in the International Chess Club is open to individuals of all ages and skill levels, with a keen interest in the game of chess. Prospective members must adhere to the club's code of conduct and abide by the rules and regulations outlined herein.2.2 Application Process.Applicants must submit a completed membership application form along with the required fee. The application will be reviewed by the club's management committee, and upon approval, the applicant will benotified of their acceptance as a member.2.3 Membership Fees.Annual membership fees are set to cover the operational costs of the club and are subject to periodic review. Members are required to pay their fees in full and on time to maintain their membership status. Failure to do so may result in the suspension or termination of membership.III. Conduct and Etiquette.3.1 Respectful Behavior.Members are expected to maintain a respectful and courteous demeanor at all times. Unacceptable behavior,such as harassment, intimidation, or disrespectful language, will not be tolerated and may result in disciplinary action.3.2 Fair Play.All members are expected to uphold the principles offair play and abide by the rules of chess. Cheating, collusion, or any other form of unethical behavior will be strictly prohibited and may lead to disciplinary sanctions.3.3 Dress Code.Members are expected to dress appropriately when attending club events. While a strict dress code is not enforced, members should ensure their attire is respectfulof the club's environment and the occasion.IV. Tournaments and Matches.4.1 Tournament Registration.Members interested in participating in tournaments or matches must register in advance and pay the required participation fee. The registration process will involve providing personal information, selecting a preferred division or category, and agreeing to abide by the tournament rules.4.2 Tournament Rules.Tournament rules will be announced prior to each event and will be strictly adhered to. Members are expected to familiarize themselves with the rules and abide by them during the tournament. Any violations may result in disqualification or other disciplinary measures.4.3 Match Scheduling.Matches between members may be arranged through the club's scheduling system or by mutual agreement between the participants. It is the responsibility of both parties to ensure that the match is played in a timely manner and that the result is reported accurately.V. Club Facilities and Resources.5.1 Usage of Facilities.Members are welcome to utilize the club's facilities and resources for practicing, playing matches, and engaging in chess-related activities. However, they are expected to respect the facility's equipment, furniture, and amenities, and to maintain a clean and orderly environment.5.2 Reservation of Facilities.Members wishing to reserve the club's facilities for private events or tournaments must do so in advance through the club's management committee. Reservations will be subject to availability and may be subject to additionalfees.VI. Disciplinary Action.6.1 Grounds for Disciplinary Action.Disciplinary action may be taken against members who violate the club's rules and regulations, including but not limited to: disrespectful behavior, unethical conduct, failure to pay membership fees, and violation of tournament rules.6.2 Types of Disciplinary Action.Disciplinary action may range from verbal warnings to suspension or termination of membership. The severity of the action will depend on the nature and severity of the offense.VII. Appeals and Complaints.7.1 Appeals Process.Members who wish to appeal a disciplinary decision or seek redress for any grievance must submit a written appeal to the club's management committee. The appeal will be reviewed, and a decision will be made in a timely manner.7.2 Complaints Procedure.Members who have a complaint about the club's operations, facilities, or the conduct of other members should submit their complaint in writing to the management committee. The committee will investigate the complaint and take appropriate action to resolve the issue.VIII. Conclusion.The rules and regulations outlined herein are.。
On the Design of S-Boxes
ON THE DESIGN OF S-BOXESA. F. Webster and S. E. TavaresDepartment of Electrical EngineeringQueen's UniversityKingston, Ont.CanadaThe ideas of completeness and the avalanche effect were first introduced by Kam and Davida [1] and Feistel [2], respectively. If a cryptographic transformation is complete, then each ciphertext bit must depend on all of the plaintext bits. Thus, if it were possible to find the simplest Boolean expression for each ciphertext bit in terms of the plaintext bits, each of those expressions would have to contain all of the plaintext bits if the function was complete. Alter-natively, if there is at least one pair of n-bit plaintext vectors X and X i that differ only in bit i ,and f X () and f X i () differ at least in bit j for all{(i,j) | 1 < i,j < n }then the function f must be complete.For a given transformation to exhibit the avalanche effect, an average of one half ofthe output bits should change whenever a single input bit is complemented. In order to determine whether a given m n ×(m input bits and n output bits) function f satisfies this requirement, the 2m plaintext vectors must be divided into 21m − pairs, X and X i , such that X and X i differ only in bit i. Then the 21m − exclusive-or sums()()V f x f x i i =⊕must be calculated. These exclusive-or sums will be referred to as avalanche vectors, each of which contains n bits, or avalanche variables.If this procedure is repeated for all i such that 1 < i < m, and one half of the avalanche variables are equal to 1 for each i , then the function f has good avalanche effect. Of course thismethod can be pursued only if m is fairly small; otherwise, the number of plaintext vectors be-comes too large. If that is the case then the best that can be done is to take a random sample of plaintext vectors X , and for each value of i calculate all the avalanche vectors V i . If approxi-mately one half the resulting avalanche variables are equal to 1 for all values of i , then we can conclude that the function has a good avalanche effect.THE STRICT AVALANCHE CRITERION AND THE INDEPENBENCE OFAVALANCHE VARIABLESThe concepts of completeness and the avalanche effect can be combined to define a new property which we shall call the strict avalanche criterion. If a cryptographic function is to satisfy the strict avalanche criterion, then each output bit should change with a probability of one half whenever a single input bit is complemented. A more precise definition of the criterion is as follows. Consider X and X i , two n-bit, binary plaintext vectors, such that X and X i differ only in bit i , 1 < i < n . LetV Y Y i i=⊕where ()Y f X =, ()Y f X i i = and f is the cryptographic transformation, under consideration.If f is to meet the strict avalanche criterion, the probability that each bit in V i is equal to 1should be one half over the set of all possible plaintext vectors X and X i . This should be true for all values of i . Again, unless n is small it would be an immense task to follow this proce-dure for all possible vector pairs X and X i .An alternate method which could be used to ascertain whether a given cryptographic transformation, f , satisfies the strict avalanche criterion would be to construct a dependence matrix. First an n-bit, random plaintext vector X is generated and its corresponding m-bit ci-phertext, ()Y f X =, is obtained (n and m will be equal if f is an invertible transformation and there is no data expansion). Then the set of n vectors(,,...,)X X X n 12is formed such that X and X j differ only in bit j. The ciphertext vectorsY Y Y n(,,...,)12=() and they are used to obtain the set of m-bit binary ava-are then found where Y f Xj jlanche vectorsV V V n(,,...,)12=⊕. This procedure is illustrated in Figure 1.such that V Y Yj jin the m x n de-The value of bit i in V j (either a 1 or a 0) is added to element a i j,pendence matrix A. This procedure is repeated for a large number, r, of randomly generatedgives the strength of plaintext vectors X, and each element in A is divided by r. Then each a i j,the relationship between plaintext bit j and ciphertext bit i. A value of 1 indicates that whenever bit j is complemented in the plaintext then the ciphertext bit i will also change its value, while a value of 0 indicates that the ciphertext bit is completely independent of the plaintext bit. If all elements in the matrix have a nonzero value then the cryptographic transformation is complete, and if it is to satisfy the strict avalanche criterion, every element must have a value close to one half. Therefore, completeness is a necessary condition if the strict avalanche criterion is to be met.A second property which would seem desirable for any cryptographic transformation is that, for a given set of avalanche vectors generated by the complementing of a single plaintext bit, all the avalanche variables should be pairwise independent. In order to measure the degree of independence between a pair of avalanche variables, we can calculate their correlation coeffi-cient. For two variables A andB [3, p.378]{}{}{}{}ρσσA B A B A B ,cov ,=where{}ρA B , = correlation coefficient of A and Bcov{A, B} = covariance of A and B= {}{}{}ΕΕΕAB A B −×{}σ2A = {}{}ΕΕA A 22−()For the case of binary variables, it can be shown that a correlation coefficient of 0means that the variables are independent. In addition, the variables will always be identical if the correlation coefficient equals 1, and a value of -1 means that they will always be comple-ments of one another [4].If either the strict avalanche criterion or the avalanche variable independence require-ment is not satisfied, then a cryptanalyst can gain some information about the statistical proper-ties of the function, which he could conceivably use to his advantage in an attack on the system.Figure 1. Part of the method for testing to see if a transformation satisfies the strict avalanche criterion:Input bit j is complemented giving V j . Each bit i, 1 < i < m, in V j is added to element a i j , inthe dependence matrix.PERFECT S-BOXESNow that these two new criteria have been presented, it would seem desirable to dis-cover how to produce cryptographic transformations which satisfy both conditions. One addi-tional condition that will be imposed on such transformations is that they be invertible. This means that there must be a one-to-one correspondence between plaintext and ciphertext vectors.If there are n input/output bits for a given function, there are ()2n! possible invertible transformations. This means that there will be approximately 2 x 1013 such functions for a four-bit system. Therefore, the search will be limited to 4 x 4 (four input/four output bit) substitution boxes (S-boxes).The initial step is to find all the potentially invertible 4x1 functions that satisfy the strict avalanche criterion, which will be combined four at a time to produce 4x 4 substitution boxes. A potentially invertible function returns a value of 1 for one half of the possible input vectors and a value of 0 for the other half. It is a necessary, but not sufficient, condition if the S-boxes formed from the single output bit functions are to be invertible. The 12,870 potentially invertible 4 x 1 functions were tested, and it was found that while 12,618 of them were com-plete, only 1368 satisfied the strict avalanche criterion [4].These 1368 functions can be divided into 9 equivalence classes or "families". Each family is closed under the following operations:plementing one or more of the input bits2.Permuting the input bitsplementing the output bitPotential invertibility and adherence to the strict avalanche criterion are preserved over these op-erations.The simplest procedure to follow in constructing the substitution boxes would be to randomly -select potentially invertible, single output bit functions from the list of those that sat-isfy the strict avalanche criterion. First, these substitution boxes are tested to see if they are in-vertible. If they satisfy the requirement, they are then examined to see if, when each input bit is complemented, the resulting avalanche variables are pairwise independent. An S-box that dis-plays both of these properties will be referred to as a "perfect" substitution box.When the method of random selection of single output bit functions was followed, the probability of the resulting 4 x 4 S-boxes being invertible was only 1.2 x 10-3, and only one S-box in 7.1 x 105 was perfect [4]. During this search, the families of single output bit functions which formed perfect S-boxes were noted. In an attempt to reduce the amount of effort required to produce perfect -boxes, the families from which the 4 x 1 functions were selected were fixed so hat only combinations which had produced perfect S-boxes in the initial search were used. This increased the frequency of occurence of perfect S-boxes by about a factor of one thousand. Several other approaches were tried which involved relaxing one or both of the strict avalanche criterion and the avalanche variable independence requirement, but none proved to be as good as choosing the single output bit functions from fixed family combinations.In the process of building these S-boxes, it was discovered that if an box is complete, or even perfect, its inverse function may not be complete. This could become important if these in-verse functions are used in the decryption process, for it would be desirable for any changes in the ciphertext to affect all bits in the plaintext in a random fashion, especially if there is not much redundancy in the original plaintext. Complete cryptographic transformations with in-verses which are complete are described as being two-way complete, and if the inverse is not complete the transformation is said to be only one-way complete.A COMPLETE S-P NETWORKKam and Davida [1] presented a method whereby an entire S-P network could be guaranteed to be complete if all the substitution boxes used in the procedure were complete. This entailed using specially designed bit permutations between the substitution layers. The networks can be of any size as long as=n k gwheren = the number of input/output bits for entire networkk = the number of input/output bits for each S-boxg = the number of substitution-permutation stages.Since completeness is a prerequisite if the strict avalanche criterion is to be met, we thought that perhaps by using perfect S-boxes in the system we could come up with a "perfect" system. A complete S-P network with n = 64, k = 4 and g = 3 was implemented. Unfortunately, it turned out that each out bit changed with a probability of only one eighth when a single input bit was complemented. In fact, it can be shown that the probability of an output changing will always be 2-g. This was termed avalanche damping. The same test was run with complete S-boxes of the type that Kam and Davida suggested in their paper instead of perfect S-boxes. The mean value of elements in the dependence matrix was slightly higher at 0.19, but their variance was over one hundred times greater than that calculated when the perfect S-boxes were used [4]. In fact, some elements had values as low as 0.01, which represents a significant shortcoming in the system.Figure 2.Mean and variance of elements in the dependence matrix for an S-P network vs. num-ber of substitution-permutation stages: All the substitution boxes in this network wereperfect, and the bit permutations were generated randomly. It is evident that the strictavalanche criterion is satisfied after approximately 12 S-P stages.This test was repeated for S-P networks with perfect S-boxes and random bit permu-tations. A plot of the mean and variance of the elements in the dependence matrix is shown in Figure 2. After three rounds, the performance is poorer than that for the complete S-P network, but after about 12 rounds the strict avalanche criterion is satisfied. This result suggests that with the addition of several S-P stages with complete or perfect S-boxes and random bit permutations, a complete S-P network could still be guaranteed to be complete and would probably satisfy the strict avalanche criterion.DESThe Data Encryption Standard (DES) has, been a federal standard in the United States since 1977. DES employs substitutions and permutations, but the algorithm is much more com-plex than the one for the complete S-P network [5].It can be shown that the DES algorithm is invertible [3, p.240]. Since the dependence matrix could, in theory, be different for every key, we cannot state that DES is always a "perfect" sys-tem. However, the results shown in Figure 3 for the key (FF . . . FF) indicate that in that case the strict avalanche criterion is satisfied. In addition, in a sample of 30 correlation coefficients picked at random, the highest absolute value found was 4.88 x 10-2. This suggests that there is very little correlation between avalanche variables. Similar results were obtained using several other key values. Thus, we can conclude that DES is a “perfect” encryption algorithm, at least for the key values that were tested.Since the S-boxes are the only nonlinear portion of the DES algorithm, their character-istics have a significant effect on the strength of the entire system. The S-boxes are not inverti-ble, but due to the way in which they are employed in the algorithm, this does not pose a prob-lem for decryption. Nor do they satisfy the strict avalanche criterion. For the entire set of 8 S-boxes, the probability that a particular output bit will change when a single input bit is comple-mented ranges from 0.43 to 0.93.The correlation coefficients between pairs of avalanche variables for the DES S-boxes were also calculated. While most of them had absolute values of less than 0.5, it was found that when input bit 1 (the least significant bit in the input) was complemented, the correlation coeffi-cients between bits 1 and 2 and between bits 3 and 4 in the output of S 4 were equal to -1. This isequivalent to the discovery made by Heilman et al. [6] that the exclusive-or sums of the output bits, y y 12⊕ and y y 34⊕, of S 4 are complemented whenever input bit x1 changes its value. Itcan also be shown that both of these results can be derived from another one of their findings()()()()()S X S X x x x x 4400000121341111⊕=⊕,,,,,where (2,1)(3,4) means that the first and second bits as well as the third and fourth bits of the following vector are interchanged.Figure 3 Mean and variance of DES dependence matrix vs. number of encryption rounds: These valuesof mean and variance are only for elements in one quarter of the dependence matrix, but Meyer[7] shows that these results will propagate through the rest of the matrix within two rounds. The strict avalanche criterion is satisfied after four rounds for this portion of the matrix; therefore, it will take six rounds before the full system will meet the requirement.ACKNOWLEDGMENTSThe authors would like to acknowledge the financial support provided by the Natural Sciences and Engineering Research Council.REFERENCES[1]Kam, J.B., and Davida, G.I.: Structured Design of Substitution Permutation EncryptionNetworks. IEEE Transactions on Computers, Vol 28, No. 10, 747 (1979)[2]Feistel, H.: Cryptography and Computer Privacy. Scientific American, Vol. 228, No. 5,15 (1973)[31Konheim, A.G.: Cryptography: a Primer. John Wiley and Sons, New York (1981)[4]Webster, A. F.: Plaintext/Ciphertext Bit Dependencies in Cryptographic Algorithms.M.Sc. thesis, Queen's University at Kingston (1985)[5]National Bureau of Standards: Data Encryption Standard. FIPS Publication 46, Wash-ington, D.C. (1977)[6]Hellman, M.E., Merkle, R., Schroeppel, R., Washington, L., Diffie, W. Pohlig, S., andSchweitzer, P.: Results of an Initial Attempt to Cryptanalyze the NBS Data Encryption Standard. SEL 76-042, Stanford University (1976)[7]Meyer, C.H.: Ciphertext/Plaintext and Ciphertext/Key Dependence vs Number of Roundsfor the Data Encryption Standard. 1978 National Computer Conference, p.1119. AFIPS Press, Montvale, New Jersey (1978)。
U4 A Red Light for Scofflaws中英对照
A Red Light for ScofflawsLaw-and-order is the longest-running and probably the best-loved political issue in . history. Yet it is painfully apparent 2 that millions of Americans who would never think of themselves as lawbreakers, let alone criminals, are taking increasing liberties with the legal codes that are designed to protect and nourish their society. 3 Indeed, there are moments today — amid outlaw litter, tax cheating, illicit noise and motorized anarchy — when it seems as though the scofflaw represents the wave of the future. 4 Harvard Sociologist David Riesman suspects that a majority of Americans have blithely taken to committing supposedly minor derelictions as a matter of course. Already, Riesman says, the ethic of U.S. society is in danger of becoming this: “You're a fool if you obey the rules.”法律和秩序，可以说是美国历史上历时最久、或许还是人们最爱谈论的政治问题。
给外星人制作一些规则和规矩英语作文
给外星人制作一些规则和规矩英语作文Creating rules and regulations for extraterrestrial beings is a task that requires careful consideration and thought. As we venture into the unknown and come into contact with alien civilizations, it becomes important to establish guidelines to ensure peaceful coexistence and mutual understanding. In this article, we will explore some of the key rules and regulations that could be put in place for interactions with extraterrestrial beings.1. Communication Protocol: The first and most important rule to establish is a communication protocol. This protocol should outline the methods of communication to be used, as well as the languages or symbols that will be used to convey messages. It is essential to establish a common ground for communication to avoid misunderstandings and misinterpretations.2. Respect for Cultural Differences: Just as we have different cultures and customs on Earth, it is likely that extraterrestrial beings will have their own unique traditions and practices. It is crucial to show respect for these cultural differences and to avoid imposing our own values and beliefs on them. By fostering an environment of cultural exchange and understanding, we can build stronger relationships with alien civilizations.3. Environmental Protection: The preservation of the environment is a universal concern that transcends boundaries and species. It is important to establish rules and regulations to protect the natural resources of a planet, whether it is inhabited by humans or extraterrestrial beings. By working together to preserve the environment, we can ensure the sustainability of our shared home in the universe.4. Non-interference Policy: In our interactions with extraterrestrial beings, it is important to adopt anon-interference policy. This means that we should refrain from interfering with the internal affairs of alien civilizations and respect their autonomy and sovereignty. By respecting the rights and values of other beings, we can foster trust and cooperation in our interactions.5. Conflict Resolution Mechanisms: In the event of disagreements or conflicts with extraterrestrial beings, it is important to have mechanisms in place for resolving disputes peacefully. This could involve mediation, arbitration, or other forms of conflict resolution that are mutually agreed upon. By establishing effective conflict resolution mechanisms, we can prevent misunderstandings from escalating into larger conflicts.6. Scientific Collaboration: One of the most exciting possibilities of interacting with extraterrestrial beings is the opportunity for scientific collaboration. By sharing knowledge, resources, and technology, we can advance our understanding of the universe and make new discoveries together. It is important to establish rules and regulations for scientific collaboration to ensure that it is conducted ethically and responsibly.7. Mutual Respect and Understanding: Above all, the most important rule to abide by in our interactions with extraterrestrial beings is mutual respect and understanding. By approaching each other with an open mind, empathy, and curiosity, we can foster positive relationships and build a foundation for meaningful interactions. By treating each other with respect and dignity, we can create a future of peace, cooperation, and mutual benefit.In conclusion, creating rules and regulations for interactions with extraterrestrial beings is a complex and challenging task that requires careful consideration and foresight. By establishing guidelines for communication, cultural exchange, environmental protection, conflict resolution, scientific collaboration, and mutual respect, we can lay the groundwork for peaceful and productive interactions with alien civilizations. As we ventureinto the unknown and reach out to the stars, let us approach our extraterrestrial neighbors with openness, humility, and a spirit of cooperation.。
范文school rules
范文school rules英文版School RulesSchool rules are essential for maintaining discipline and ensuring a safe and effective learning environment. They are designed to guide students, teachers, and staff in their conduct within the school premises, promoting respect, responsibility, and cooperation.Firstly, punctuality is paramount. Arriving on time for classes and meetings is crucial to maintain the flow of the school day. It also sets a precedent for respecting others' time and efforts.Secondly, dress code regulations are imposed to promote a professional and formal learning atmosphere. Students are encouraged to dress appropriately, avoiding casual or inappropriate attire that may distract from the learning process.Thirdly, the school expects students to respect the property of the institution and fellow students. Vandalism, graffiti, and the misuse of school resources are strictly prohibited.Moreover, bullying and harassment are not tolerated. The school strives to create a safe and inclusive environment where everyone is treated with dignity and respect. Students are expected to treat each other kindly, fostering a positive school culture.Lastly, the use of electronic devices such as phones and laptops is restricted during class time. This is to ensure maximum attention and focus on the learning activities conducted in class.In conclusion, school rules are not mere regulations but guidelines that promote discipline, respect, and safety within the academic community. Following these rules is crucial for a positive and productive school experience.中文版学校规则学校规则对于维护纪律和确保安全有效的学习环境至关重要。
schooi rules作文
schooi rules作文School Rules.As members of a school community, it is essential to adhere to certain rules and regulations to maintain order, safety, and a conducive learning environment. School rules are established to ensure the well-being of all students and staff, and it is our responsibility as individuals to respect and follow them.遵守校规的益处。
There are numerous benefits to following school rules. Firstly, it creates a safe and orderly environment. When students adhere to rules such as staying within designated areas, following safety procedures, and respecting the property of others, they contribute to a positive and secure atmosphere where everyone can feel comfortable and focused.Secondly, following school rules promotes discipline and self-control. By adhering to regulations, students learn to regulate their behavior, manage their emotions, and develop a sense of responsibility. This self-discipline translates into other areas of life, helping students become more successful in their studies, personal relationships, and future careers.Thirdly, adherence to school rules fosters respect for authority. By following the instructions of teachers, administrators, and other school staff, students learn to value and respect those in positions of leadership. This respect extends beyond the school environment and helps students develop a greater appreciation for authority figures throughout their lives.后果 of Violating School Rules.Consequences of violating school rules vary depending on the severity of the offense and the individual school's policies. Common consequences may include:1. Verbal warnings.2. Detention.3. Suspension.4. Expulsion.In addition to these formal consequences, breaking school rules can also have negative social and emotional consequences. Students who violate rules may face disapproval from their peers, damage their relationships with teachers and administrators, and experience a loss of trust.Conclusion.School rules are essential for maintaining a safe, orderly, and productive learning environment. By adhering to these rules, students create a positive atmosphere, develop self-discipline, and foster respect for authority. Conversely, violating school rules can have negativeconsequences, both formally and informally. It is the responsibility of all members of the school community to follow and uphold school rules to ensure the well-being of all.中文回答：学校规则。
旅游景点需要遵守的规则英语作文
旅游景点需要遵守的规则英语作文Rules to Follow at Tourist AttractionsHi everyone! My name is Emily, and I'm 10 years old. I love going on trips and visiting cool places with my family. We've been to lots of tourist attractions like museums, national parks, historic sites, and even theme parks. It's always so much fun to learn about new things and see amazing sights.But you know, there are certain rules we need to follow when we go to these places. The rules are there to keep us safe, respect the attraction, and make sure everyone has a good time. I'm going to share some important rules that we should all remember the next time we visit a tourist spot.First, we have to obey all the signs and instructions. The signs are put there by people who work at the attraction to guide us. For example, if a sign says "Do Not Touch", we shouldn't touch anything, even if we really want to. Things can get damaged or broken easily. At museums, we have to be very careful around the exhibits because many of them are old, valuable, and fragile.Another rule is to stay on the designated paths and trails. We can't just go wandering off wherever we want. That's dangerousbecause we could get lost or hurt. Plus, we might trample on plants or disturb animals in their natural habitats. Trust me, you don't want to surprise a bear or mountain lion! The paths are marked to keep us safe and protect nature.It's also very important to throw away any trash or recycling in the proper bins. We can't just litter everywhere! That makes the place look messy and ruins it for other visitors. It's also bad for the environment and can harm plants and animals. Pack out whatever you packed in.When we're indoors at places like museums or historic buildings, we need to use our indoor voices and walk calmly. No running, shouting, or being too rowdy. We have to be respectful of others trying to enjoy the exhibits too. These places aren't playgrounds!Speaking of being respectful, we should always follow the cultural customs and traditions. At religious sites, we may need to cover our heads, take off our shoes, or stay quiet. We have to be mindful of how we act and dress. It's their sacred place, so we need to do what they ask of us.Now, taking pictures is usually okay, but we have to check the rules first. Some attractions don't allow any photography at all. And even if they do allow it, we should never use a flash nearvaluable items because it can cause damage over time. Always ask before taking pics!If we get separated from our parents or group, it's important to stay calm and go to the designated meeting spot right away. Don't just wander off trying to find them. There will be staff there who can help reunite us with our families safely.There might be some areas that are off-limits or under construction. We have to pay attention to any restricted areas and detours. Those places are closed for good reasons, like safety hazards or protecting nature. We can't just go wherever we want!Finally, we need to be respectful of all the staff and park rangers working at these attractions. They are there to help us and keep everything running smoothly. We should listen to any instructions they give us and be patient if there are lines or crowds. Getting upset won't help anyone.Those are some of the most important rules I can think of for visiting places like museums, parks, historical sites, and other tourist attractions. Rules aren't fun, but they are necessary. As long as we follow them, we can have an amazing time learning about the world around us. Plus, we'll be setting a great example for others to follow the rules too!It's up to all of us to be responsible and respectful visitors. That's how we can protect these amazing places for many years to come so that other kids like me can experience them too. So remember the rules, have fun, and make some incredible memories!。
关于美术馆的规则英语作文初一
关于美术馆的规则英语作文初一英文回答：Museum Rules: A Guide to Proper Etiquette.When visiting a museum, it is important to observe proper etiquette to ensure a respectful and enjoyable experience for all. Here are some general rules to follow:1. Be respectful of the artwork and exhibits.Avoid touching or handling any artwork or exhibits unless explicitly permitted. Use the provided viewing platforms and do not lean over or crowd the pieces. Maintain a respectful distance from fragile or valuable items.2. Stay quiet and avoid talking excessively.Museums are places of contemplation and study. Keepyour voice low and avoid loud conversations or noises that might disturb other visitors. If you have questions or need assistance, approach a museum staff member discreetly.3. No photography or recording without permission.Many museums have strict policies regarding photography and recording. Check the guidelines at the entrance or ask a staff member for permission before using cameras or recording devices. Flash photography is often prohibitedfor the preservation of the artwork.4. No food or drinks in the galleries.Food and drinks can damage or contaminate artwork and exhibits. Refrain from bringing any food or beverages into the galleries. Designated areas, such as cafeterias or designated seating zones, are usually provided for refreshments.5. Be aware of your surroundings and stay alert.Pay attention to the location of fire exits andsecurity measures. Report any suspicious activity or emergency situations to a museum staff member immediately. Keep your personal belongings secure and avoid leaving valuables unattended.6. Follow the designated pathways.Most museums have designated pathways and flow patterns to guide visitors through the exhibits. Stay within the designated areas and avoid cutting through ropes orbarriers to access restricted areas.7. Respect the time and space of others.Allow other visitors ample time and space to view the exhibits. Avoid overcrowding or pushing your way through crowds. Be patient and courteous to all other guests.8. Ask for assistance or information when needed.Museum staff members are there to help. Do not hesitateto approach them if you have questions, need assistance, or require special accommodations. They can provide valuable information and make your visit more enjoyable.9. Support the museum by purchasing tickets or making donations.Admission fees and donations help support the museum's operations and maintenance. Consider purchasing tickets or making a donation to contribute to the preservation and accessibility of these cultural institutions.10. Be a responsible museum visitor.Follow these rules and guidelines to ensure arespectful and enriching experience for yourself and others. Remember that museums are places for education, appreciation, and enjoyment.中文回答：美术馆规则，正确礼仪指南。
英语作文第四单元校规
英语作文第四单元校规英文回答：# School Rules: Maintaining Order and Safety.School rules are an essential aspect of any educational institution. They establish clear expectations for conduct and behavior, ensuring a safe and conducive learning environment for all students. Without rules, schools would descend into chaos and disorder.Importance of School Rules.1. Safety and Security: Rules help ensure the physical and emotional safety of students. They establish boundaries, prohibit dangerous behaviors, and define consequences for unacceptable actions.2. Order and Discipline: Rules create an orderly and structured environment where students can focus on learning.They prevent disruptions and distractions, allowing teachers to effectively deliver instruction.3. Respect and Responsibility: Rules promote respect among students, teachers, and administrators. They encourage students to be accountable for their actions and to treat others with dignity.4. Equity and Fairness: Rules ensure that all students are treated fairly and equitably. They establish clear standards of conduct that apply to everyone, regardless of background or circumstance.5. Student Development: Rules help students develop self-discipline, problem-solving skills, and a sense of community. They teach students the importance of adhering to expectations and respecting authority.Types of School Rules.School rules can be categorized into several types:1. General Conduct: These rules apply to all students and include expectations regarding behavior in the classroom, hallways, and common areas.2. Academic Integrity: These rules prohibit plagiarism, cheating, and other forms of academic dishonesty.3. Dress Code: These rules define appropriate attirefor school, ensuring that students are dressed respectfully and appropriately for the learning environment.4. Technology Usage: These rules regulate the use of electronic devices in school, including cell phones, laptops, and tablets.5. Safety and Emergency Procedures: These rules outline specific protocols to follow in case of emergencies, such as fire drills, earthquakes, or lockdowns.Enforcement of School Rules.The enforcement of school rules is essential to theireffectiveness. Teachers, administrators, and other school staff must work together to ensure that rules are consistently enforced. Consequences for breaking rules should be clear, fair, and appropriate to the severity of the infraction.Conclusion.School rules play a crucial role in creating a safe, orderly, and conducive learning environment for students. They establish expectations, promote respect, and ensure equity and fairness. By adhering to these rules, students can create a positive and productive atmosphere where they can thrive academically and socially.中文回答：学校规则，维持秩序和安全。
在历史博物馆必须遵守的规则英语作文
在历史博物馆必须遵守的规则英语作文Rules to Follow at the History MuseumHi there! My name is Lily and I'm 10 years old. Last weekend, my class went on a field trip to the big history museum downtown. It was so much fun seeing all the old artifacts and learning about how people lived a long time ago. But before we went inside, our teacher Mrs. Martinez went over some really important rules we all had to follow. She said if we didn't listen, we might not be allowed back! So I paid close attention because I definitely want to go back to that awesome museum again.The first rule is that we had to stay with our group and teacher the whole time. We couldn't wander off by ourselves, even for a second! Mrs. Martinez said it's really easy to get lost in a huge place like that with so many exhibits and hallways. Plus, there would be lots of other school groups there too, so we had to stick together. If we needed to go to the bathroom, we had to ask a grownup to take us.Another big rule was no running, jumping, shoving or horseplay of any kind. The museum has so many priceless treasures and artifacts that are thousands of years old. Just imagine if you accidentally knocked over a vase from ancientEgypt or broke a remnant of the Great Wall of China! You'd get in super big trouble and might even have to pay a lot of money to replace it. No thanks! We had to walk carefully, keep our hands to ourselves and be on our very best behavior.We also couldn't shout, scream or make loud noises. Can you imagine how annoying that would be for everyone else trying to look at the exhibits? All the loud sounds might damage the old stuff too. We had to use our inside voices and be quiet and respectful. If we wanted to say something, we had to whisper it.Speaking of respecting the museum, we couldn't eat any food or candy inside either. Could you imagine if someone spilled their juice box or dropped their granola bar all over a 500-year-old painting? What a disaster! We had to leave all snacks and drinks in the lunchroom. Water bottles were okay though, as long as we kept them closed and in our bags.And I probably don't even need to say this, but we absolutely, positively could NOT touch anything on display unless there was a sign saying we could. All that old stuff is too fragile and valuable to be poked and prodded by grabby hands. We had to keep our hands behind our backs or in our pockets the whole time. No touching!But probably the most important rule of all is that we had to listen to our teacher, the museum staff and any guards or security people we saw. If they told us to do something, we had to do it right away without arguing or backtalk. They know how to keep us and the exhibits safe, so we owed them our full respect and cooperation at all times.Mrs. Martinez promised that if we followed all the rules, we'd have an awesome time exploring the museum's exhibits about ancient civilizations, early American history, world cultures and more. But she warned that if anyone broke a rule, we might get kicked out or not be allowed back for future field trips. Yikes!It was really hard to keep all those rules straight, but we managed it. Well, except for Billy Johnson who tried to sneak a peanut butter crackers into the Egyptian mummy room. The guard caught him and gave the whole class a super stern look. We all had to sit through a lecture on why food isn't allowed. Oops! Poor Billy's face was as red as a tomato.Other than that, we were all perfect angels. We listened to the tour guides, stayed with our group, walked slowly and kept our hands off everything. I saw so many cool things, like:A skeleton of a Tyrannosaurus rex that lived 65 million years ago! It was ginormous.Traditional clothing and masks from ancient Mayan and Incan cultures. The colors and designs were beautiful.A real suit of armor worn by a knight from the Middle Ages. I can't imagine going into battle wearing all that heavy metal!Arrowheads, tools and pottery made by Native American tribes centuries ago. The craftsmanship was incredible.Paintings, books, furniture and clothes showing how people lived in Colonial America in the 1700s.Old guns, swords, canons and tanks used in different wars throughout history. That stuff looked terrifying!I could go on and on, but I think you get the idea. The history museum was so fascinating and I learned a ton. Just thinking about it makes me want to go back again and again! But I'll make sure to review all the rules first so I can continue being on my best behavior.If you ever get to go to a museum like that, I hope you'll remember to follow proper museum etiquette too. Don't touch anything unless you're allowed, keep your voices down, stay with your group and most of all, soak up all the amazing knowledge and history on display! Museums are wonderful places where we can learn so much about our world. But we have to beresponsible visitors in order to protect the priceless treasures they contain. Follow the rules, and you're guaranteed to have an awesome time traveling back through the centuries.。
校规校训的英语作文
校规校训的英语作文School rules and school motto are important for maintaining order and discipline in the school environment. They provide guidelines for students to follow and help create a positive and respectful atmosphere for learning.School rules are designed to ensure the safety andwell-being of all students and staff. They cover a wide range of areas, including behavior, dress code, attendance, and academic integrity. By following these rules, students can contribute to a harmonious and productive learning environment.The school motto serves as a guiding principle for students to live by. It often embodies the values of the school and encourages students to strive for excellence, respect others, and take responsibility for their actions. By embracing the school motto, students can develop a strong sense of character and integrity.Adhering to school rules and embracing the school motto not only benefits the individual student, but also the entire school community. It fosters a sense of unity and cooperation among students, teachers, and staff, creating a supportive and inclusive environment where everyone can thrive.In conclusion, school rules and school motto play a crucial role in shaping the school culture and promoting a positive learning environment. By following these guidelines and embodying the values of the school motto, students can contribute to a respectful and harmonious community where everyone has the opportunity to succeed.。
英语作文,介绍迪士尼的规则
介绍迪士尼规则的英语作文1Disneyland is a magical place that attracts countless visitors. However, to ensure a pleasant and safe experience for everyone, there are certain rules that need to be followed.When entering the park, some items are strictly prohibited. For instance, sharp objects, large coolers, and outside food and beverages are not allowed.The use of rides and attractions also has specific regulations. For popular rides, there is often a long queue, and visitors are required to wait patiently in an orderly manner. When it's your turn to ride, you must fasten your seatbelts and follow the instructions of the staff.As for visitor behavior, it's essential to keep public areas clean. Littering is not acceptable. Moreover, respecting other visitors is of utmost importance. Do not push or cut in lines, and avoid loud and disturbing noises.By adhering to these rules, we can all enjoy the wonder and joy that Disneyland has to offer. Let's make our visit to Disneyland a memorable and pleasant one for ourselves and others.2Disneyland is a magical place that attracts millions of visitors everyyear. However, to ensure the safety and order of all guests, there are certain rules that everyone must follow.First and foremost, safety is of paramount importance. To protect visitors, there are various safety measures in place. For instance, in thrill rides, there are secure seat belts and harnesses. Alongside the rides, there are clear warning signs indicating height restrictions and health warnings.When it comes to watching shows, guests are expected to remain quiet and respect the seating arrangements. This not only allows everyone to enjoy the performance but also ensures a smooth and pleasant experience for all. Disruptive behavior such as talking loudly or standing up randomly is strictly prohibited.Another important rule is queuing orderly. Visitors should wait in line patiently without pushing or cutting in. This helps to maintain a fair and efficient environment for everyone.In conclusion, these rules at Disneyland are not meant to restrict but to safeguard and enhance the enjoyment of every visitor. By adhering to them, we can all have a wonderful and safe time in this enchanting world.3Disneyland is not just a place of magic and fun; it also has strict environmental rules that contribute to a sustainable and enjoyable experience for all. One of the notable rules is the emphasis on waste sorting. Guests are expected to separate their trash into different categories such asrecyclables, organic waste, and non-recyclables. This helps in reducing the amount of waste that ends up in landfills and promotes the recycling process.Another important rule is the reduction of single-use items. For instance, instead of providing disposable cups and straws, Disneyland encourages guests to bring their reusable ones. This not only cuts down on plastic waste but also raises awareness about the negative impact of single-use plastics on the environment.Furthermore, the park has regulations on energy conservation. Lights and attractions are designed to be energy-efficient, and there are reminders for guests to turn off unnecessary electronics to save power.By following these green rules, visitors not only enjoy the enchanting attractions but also actively participate in protecting the environment. It is a collective effort to ensure that Disneyland remains a wonderland for generations to come.4Disneyland is a magical place that attracts millions of visitors every year. However, like any large entertainment venue, it has specific rules in place for special circumstances.When bad weather strikes, such as thunderstorms or strong winds, the operation of some rides may be temporarily suspended for the safety of guests. This decision is not taken lightly. The staff constantly monitor theweather conditions and make judgments based on strict safety standards. They understand that guests may be disappointed, but safety always comes first.In the event that a visitor suddenly feels unwell, Disney has well-organized emergency response rules. Trained medical personnel are on standby to provide immediate assistance. If necessary, they will coordinate with local medical facilities to ensure the visitor receives appropriate treatment. Special areas are designated for providing first aid and calming the situation.These rules are not just bureaucratic formalities but a demonstration of Disney's commitment to the well-being and safety of every guest. They ensure that even in unexpected situations, the magic of the Disney experience remains intact while prioritizing the health and security of all.5When it comes to visiting Disneyland, there are several fascinating service rules that greatly enhance the visitor experience. One of the most important rules is the acquisition and usage of FastPass. To get a FastPass, you need to find the dedicated machines located near popular attractions. You can only obtain one FastPass at a time, and there is a specific time interval before you can get the next one. This rule ensures that the waiting time for rides is significantly reduced, allowing you to enjoy more attractions in a shorter period.Another delightful rule is about interacting with the Disney characters. You might come across these beloved figures in designated areas. When approaching them, it's essential to be polite and show your enthusiasm. Remember not to rush or push others. It's a magical moment that should be shared with kindness and respect.Disneyland also has rules for queuing. Stand in an orderly manner and follow the instructions of the staff. This not only keeps everything running smoothly but also adds to the overall pleasant atmosphere of the park.In conclusion, these rules at Disneyland are designed to make your visit as wonderful and memorable as possible. By following them, you'll have an enchanting time filled with joy and magic.。
为什么要遵循图书馆规则英文作文
为什么要遵循图书馆规则英文作文The Paramount Importance of Adhering to Library Rules.Libraries, revered as sanctuaries of knowledge and intellectual exploration, serve as essential cornerstones of our educational and cultural landscapes. To ensure that these invaluable institutions remain havens of learning and discovery, it is imperative that patrons strictly adhere to the established rules and regulations. These guidelines are not mere arbitrary impositions but rather indispensable pillars that safeguard the integrity, functionality, and accessibility of libraries for all.Preserving the Collection: A Shared Responsibility.The preservation of library collections is paramount, as they represent a collective heritage passed down through generations. Rare manuscripts, centuries-old tomes, and invaluable artifacts are entrusted to libraries for safekeeping and public access. Failure to comply withlibrary rules can inadvertently damage or destroy these precious resources, depriving future generations of their wisdom and inspiration.For instance, the improper handling of books, such as bending their spines, turning down pages, or writing on their margins, can irreparably damage their physical integrity. Similarly, consuming food or beverages while handling library materials can lead to stains and contamination, rendering them unusable. Adhering to the designated areas for eating and drinking helps protect the collection from potential harm.Respecting the Environment: Creating a Conducive Space.Libraries are communal spaces where individuals gather to delve into the written word, engage in research, and seek knowledge. Maintaining a respectful and conducive environment is essential for all patrons to fully benefit from the library's resources and services.Loud conversations, disruptive behavior, or the use ofelectronic devices without headphones can disturb othersand impede their ability to concentrate. Following thelibrary's guidelines regarding noise levels and deviceusage ensures that everyone has an equally enjoyable and productive experience. Maintaining proper hygiene, such as refraining from smoking or wearing strongly scented perfumes, also contributes to a pleasant and welcoming atmosphere.Promoting Equitable Access: Sharing the Resources.Libraries strive to provide equal access to information and resources for all members of the community. However,this can only be achieved when patrons are mindful ofothers' needs and follow the established borrowing policies.Overdue or lost books deprive other patrons of the opportunity to benefit from those resources. Promptly returning or renewing borrowed materials ensures theirtimely availability for others. Similarly, excessive borrowing or hoarding books can limit access for those who may need them more urgently. Staying within the designatedborrowing limits promotes equity and fairness among all library users.Protecting the Library: Ensuring its Longevity.Libraries are vulnerable to theft, vandalism, and other forms of misconduct that can jeopardize their ability to serve the community. By adhering to library rules, patrons play a vital role in protecting this invaluable resource.Reporting suspicious activities, such as unauthorized entry or suspicious behavior, to library staff helps ensure the safety and security of the premises and its contents. Respecting closing times prevents unauthorized access and reduces the risk of damage or theft. Avoiding excessive noise or engaging in disruptive activities contributes to a secure and welcoming environment for all.In conclusion, adhering to library rules is not merely a matter of compliance but rather an essential act of respect, responsibility, and community spirit. By embracing these guidelines, patrons contribute to the preservation ofpriceless collections, foster a respectful and inclusive environment, promote equitable access to resources, and safeguard the longevity of these cherished institutions. As stewards of our shared intellectual heritage, it is incumbent upon us all to uphold the rules and regulations that ensure the enduring vitality of our libraries.。
Cutting-Edge_Laboratories_of_Shared_Humanity
A large “cellular wall” at the Shanghai NaturalHistory Museum brings sunlight into the atrium, M O S A I Callowing visitors to enjoy natural lighting fromthe third underground floor. The museum hastwo floors above ground and three underground.(Photo by Dong Fang/China Pictorial) ArrayCopyright©博看网. All Rights Reserved.Cutting-Edge Laboratories of Shared Humanity Text by Irina BokovaMuseums are hubs of constant dialogue within and among countries that foster knowledge about the incredible cultural diversity of humanity.working closely with the International Council of Museums (ICOM), also created by UNESCO. But so much has changed since then. UNESCO has stayed engaged not only by supporting the ICOM, but also by investing in major intercul-tural projects in which museums have played a prominent role. Considering the Silk Road’s endur-ing legacy of connecting civilizations throughout history, the UNESCO Silk Roads Programme, launched in 1988, continues to revive and expand these historic networks in a digital space, bringing people together in an ongoing dialogue and fostering a mutual understanding of diverse and ofteninterrelated cultures along these routes. The author served two terms as the director-general of UNESCO from 2009 to 2017.T oday, museums are not only repositories for objects, but centers of knowledge exchangeand social connection. Through thesoft power of cultural diplomacy,museums become spaces to fosterawareness of our shared history andtransmit common values. These ideasresonated deeply during my experi-ence as director-general of UNESCO.In the 1960s, UNESCO launchedthe pioneering “Imaginary Museum”project to increase global access to artthrough reproduction of the world’smost famous paintings. UNESCOthen adopted its first recommenda-tion on museums, seeking to makethem accessible to everyone byC H I N A P I C TO R I A L55Copyright©博看网. All Rights Reserved.own history and culture, as well as those of other histories and cultures. They are places where people come together as one single community, showcasing the wealth of diversity. They are places to wonder, to learn about the past, and to invent the future.I see museums as cutting-edge laboratories of our shared human-ity helping to protect our heritage, catalyze new creativity, find words and images to capture the complexity of our world, and to foster under-standing of others. I firmly believe in the power of museums to rejuvenate urban policies, deepen social inclu-sion, create jobs, foster a sense of belonging, make the most of cultural heritage for all, and contribute to mutual understanding in a complex world.This is the spirit of UNESCO’s Recommendation Concerning the Protection and Promotion of Museums and Collections , adopted in November 2015. It seeks to promote the role of museums in fostering ideals of tolerance and mutual under-standing. The recommendation recognized that “the preservation, study, and transmission of cultural and natural, tangible, and intan-gible heritage, in its movable and immovable conditions, are of great importance for all societies, for inter-cultural dialogue among peoples, for social cohesion, and for sustainable development.”All these ideas were very well captured at UNESCO’s High-Level Forum on Museums, held in Shenzhen, Guangdong Province, from November 10 to 12, 2016, following the adoption of the recom-mendation. I had the privilege of participating in it. I believe these words have not aged a day. At the heart of our cities, museums are much more than cultural spaces to display collec-tions. They are hubs of constant dialogue within and among countries and bastions of knowledge about the incredible cultural diversity of humanity. The Programme has a very rich legacy of movable heritage displayed in museums along the lengths of these routes. Since 2017, these museums have been presented and promoted by an online platform, connecting the historic cultural legacy of the Silk Road around the world—from Xi’an to Venice and all the way through Baghdad, Samarkand, the Balkans, and other places.For millennia, the wondrous story of the Silk Road has been one of encounters between people, cultures, religions, and knowledge. These encounters have shaped civilization over the ages, catalyzing inventions and fertilizing intellectual scholar-ship. They gave birth to literary and scientific treasures and to traditions and artistic practices that have been passed across generations.And all the glorious stories of human encounters can be found in museums. Generally, they are places where people meet to share ideas, innovate and learn more about their A child enjoys the Silk Road exhibits including pottery figurines from the Tang Dynasty (618-907) at the National Museum of China, May 6, 2023. (Photo by Qin Bin/China Pictorial)56 V O L U M E 896M O S A I CCopyright ©博看网. All Rights Reserved.。
于对区爱美学校高考英语二轮小专题复习 落实用之文化教育型阅读理解2
于对区爱美学校专题限时训练(十七) [文化教育型阅读理解(二)](限时：25分钟)AMillions of people pass through the gates of Disney's entertainment parks in California, Florida and Japan each year. What makes these places an almost universal attraction? What makes foreign kings and queens and other important people want to visit these Disney parks? Well, one reason is the way they're treated once they get there. The people at Disney go out of their way to serve their “guests”， as they prefer to call them, and to see that they enjoy themselves.All new employees, from vice presidents to parttime workers, begin their employment by attending Disney University and taking “Traditions 1”. Here, they learn about the company's history, how it is managed and why it is successful. They are shown how each department relates to the whole. All employees are shown how their part is important in making the park a success.After passing “Traditions 1”， the employees go on to more specialized training for their specific jobs. No detail is missed. A simple job like taking tickets requires four eighthour days of training. When one ticket taker was asked why it took so much training for such a simple, ordinar y job, he replied, “What happens if someone wants to know where the restrooms are, when the parade starts or what bus to take back to the campgrounds？…We need to know the answers or where to get them quickly. Our constant aim is to help our guests enjoy th e party.”Even Disney's managers get involved in the daily management of the park. Every year, the managers leave their desks and business suits and put on special service clothes. For a full week, the bosses sell hot dogs or ice cream, take tickets or drive the monorail (单轨车), and take upany of the 100 jobs that make the entertainment park come alive. The managers agree that this week helps them to see the company's goals more clearly.All these efforts to serve the public well have made Walt Disney Productions famous. Disney is considered by many as the best mass service provider in America or the world. As one long time business observer on ce said, “How Disney treats people, communicates with them, and rewards them, is in my view the very reason for his fifty years of success…I have watched, very carefully and with great respect and admiration, the theory and practice of selling satisfaction and serving millions of people on a daily basis, successfully. It is what Disney does best.”1. The first day they come to Disney parks, all new employees ________．A．begin as ticket takersB．must learn several jobsC．begin by receiving onthejob trainingD．have already attended Disney University2. The main goal of the Disney employees is to ________．A．learn all parts of the businessB．keep their important guests happyC．be able to answer all kinds of questionsD．see that their guests enjoy themselves3. Each year, managers wear special service clothes and work in the park to ________．A．gain a better view of the company's objectivesB．remind themselves of their beginnings at DisneyC．set a good example for employeesD．replace employees on holiday4. Which of the following is NOT true according to the passage?A．Parades are regularly held in Disney's entertainment parks.B．Disney attracts people almost from all over the world.C．Tourists learn the history of Disney in its entertainment parks.D．Disney's managers are able to do almost all kinds of work in the Disney parks.5. This passage is mainly about ________．A．how Disney employees are trainedB．the history and traditions of the Disney enterprisesC．the importance Disney places on serving people wellD．why Disney enterprises make a lot of moneyBBicycle SafetyOperation Always ride your bike in a safe, controlled manner on campus(校园). Obey rules and regulations. Watch out for walkers and other bicyclists, and always use your lights in dark conditions.Theft Prevention Always securely lock your bicycle to a bicycle rack—even if you are only away for a minute. Register your bike with the University Department of Public Safety. It's fast, easy, and free. Registration permanently records your serial number, which is useful in the possible recovery of the bike stolen.EquipmentBrakes Make sure that they are in good working order and adjusted properly.Helmet Make sure your helmet meets current safety standards and fits properly.Lights Always have a front headlight—visible at least 500 feet in front of the bike. A taillight is a good idea.Rules of the RoadRiding on Campus As a bicycle rider, you have a responsibility to ride only on streets and posted bicycle paths. Riding on sidewalks or other walkways can lead to a fine. The speed limit for bicycles on campus is 15 mph, unless otherwise posted. Always give the right of way to walkers. If you are involved in an accident, you are required to offer appropriate aid, call the Department of Public Safety and remain at the scene until the officer lets you go.Bicycle Parking Only park in areas reserved for bikes. Trees, handrails, hallways, and sign posts are not for bicycle parking, and parking in such spots can result in a fine.If Things Go WrongIf you break the rules, you will be fined. Besides violating rules while riding bicycles on campus, you could be fined for：No bicycle registration$25Bicycle parking banned$30Blocking the path with the bicycle$40Violation of bicycle equipment requirement$351．Registration of your bicycle may help you ________.A．find your stolen bicycleB．get your serial numberC．receive free repair servicesD．settle conflicts with walkers2．According to the passage, what bike equipment is a free choice for bicycle riders?A．Brakes. B．A helmet.C．A headlight. D．A taillight.3．When you ride a bicycle on the campus, ________.A．ride on posted bicycle paths and sidewalksB．cycle at a speed of over 15 mphC．put the walkers' right of way firstD．call the police before leaving in case of an accident4．If you lock your bicycle to a tree on the campus, you could be fined ________.A．$25 B．$30 C．$35 D．$405．What is the passage mainly about?A．A guide for safe bicycling on the campus.B．Directions for bicycle tour on the campus.C．Regulations of bicycle race on the campus.D．Rules for riding motor vehicles on the campus.CAs computers become more popular in China, Chinese people are increasingly relying on computer keyboards to input Chinese characters. But if they use the computer too much, they may end up forgetting the exact strokes(笔画)of each Chinese character when writing on paper. Experts suggest people, especially students, write by hand more.Do you write by hand more or type more? In Beijing, students start using a computer as earlyas the primary school. And computer dependence is more widespread among university students. Almost all their assignments and essays are typed on a computer.All the students interviewed say they usually use a computer.It's faster and easier to correct if using a computer. And that's why computers are being applied more and more often to modern education. But when people are taking_stock_in computers increasingly, problems appear.“When I'm writing with a pen, I find I often can't remember how to write a character, though I feel I'm familiar with it.”“I'm not in the mood to write when faced with a pen and paper.”Many students don't feel this is something to worry about. Now that it's more convenient and efficient to write on a computer, why bother to handwrite?Many educators think differently. Shi Liwei, the headmaster of a famous primary school in the capital said，“Chinese characters enjoy both practical and aesthetic(审美的) value. But those characters typed with computer keyboards only maintain their practical value. All the artistic beauty of the characters is lost. And handwriting contains the writer's emotion. Through one's handwriting, people can get to know one's thinking and personality. Beautiful writing will give people a better first impression of them.”To encourage students to handwrite more, many primary schools in Beijing have made writing classes compulsory(必修的)and in universities, some professors are asking students to turn in their homework and essays written by hand.1. Which of the following can best serve as the title of the passage?A．The importance of handwriting and typingB．To type or to handwrite?C．Writing by computer will replace writing by handD．Practical and aesthetic value of Chinese characters2. The students interviewed prefer to write using a computer mainly because________．A．they are usually asked to email their homework and essaysB．they can correct the mistakes they make quickly and convenientlyC．they find it not easy to remember how to write a characterD．computers have become a trend and fashion in China3. Which of the following statements is NOT true of the advantages of handwriting? A．Handwriting contains the writer's emotion.B．The writer's thinking and personality are shown in his or her handwriting. C．Handwriting can impress people well and build one's selfconfidence.D．Chinese characters enjoy both practical and aesthetic value.4. The underlined expression “taking stock in”(Paragraph 4) probably means “________”．A．getting bored withB．getting dependent onC．becoming crazy aboutD．getting curious about5. We can draw the conclusion from the passage that________．A．more and more students will give up writing on a computerB．writing by hand will give way to typing by computer one dayC．more and more students will pay attention to handwritingD．the typing article better expresses one's emotion and quality专题限时训练(十七)A【要点综述】本文主要介绍了迪斯尼公司通过严格的训练管理和优质的服务吸引了来自世界各地的人们。
遵守学校安全规章制度英语
遵守学校安全规章制度英语As students, it is our responsibility to abide by the safety rules and regulations set forth by our school. These rules are put in place to ensure the well-being and security of everyone in the school community. By following these rules, we can create a safe and positive learning environment for all.1. Dress CodeOne of the most basic safety rules in our school is the dress code. It is important to dress modestly and appropriately for school. This means avoiding clothing that is revealing, offensive, or disruptive to the learning environment. By following the dress code, we can show respect for ourselves and others.2. AttendanceRegular attendance is crucial for academic success. It is important to attend all classes and arrive on time. If you are absent, it is important to provide a valid excuse and make up any missed work. By attending class regularly, we can stay on top of our studies and forge a path to success.3. Respect for Teachers and StaffRespect for teachers and staff is another key component of school safety. It is important to treat all school personnel with courtesy and kindness. This means following their instructions, listening attentively, and showing appreciation for their hard work. By respecting our teachers and staff, we can create a positive and supportive learning environment.4. Proper Use of TechnologyIn today's digital age, technology plays a huge role in our education. It is important to use technology responsibly and in accordance with school policies. This means avoiding inappropriate websites, refraining from cyberbullying, and using technology for educational purposes only. By using technology responsibly, we can ensure a safe and productive learning environment.5. Avoiding Drugs and AlcoholDrugs and alcohol have no place in our school community. It is important to avoid using drugs and alcohol on school grounds or at school events. By refraining from these substances, we can protect our health and safety, as well as the well-being of our classmates.6. Reporting Bullying and HarassmentBullying and harassment have no place in our school. It is important to report any incidents of bullying or harassment to a teacher, counselor, or administrator. By speaking up andstanding up against bullying, we can create a safe and inclusive school environment for all students.7. Fire and Emergency DrillsFire and emergency drills are held regularly in our school to prepare us for unexpected situations. It is important to take these drills seriously and follow instructions carefully. By practicing fire and emergency drills, we can be prepared to respond quickly and safely in case of an emergency.8. Respect for School PropertyRespect for school property is essential to maintaining a clean and welcoming learning environment. It is important to take care of school property, such as desks, books, and equipment. By treating school property with respect, we can create a positive learning environment for ourselves and others.9. Safe TransportationIf you travel to school by bus, bike, or car, it is important to do so safely. Follow traffic rules, wear a helmet while biking, and be mindful of your surroundings. By practicing safe transportation, we can ensure our journey to and from school is secure and stress-free.10. Reporting Safety ConcernsIf you notice any safety concerns or hazards in our school, it is important to report them to a teacher or administrator immediately. By speaking up about safety concerns, we can work together to address and resolve any potential risks.In conclusion, school safety rules and regulations are in place to protect and support all members of the school community. By following these rules, we can create a safe, respectful, and positive learning environment for everyone. Let us all work together to uphold these rules and ensure the well-being of our school community.。
关于美术馆的规则英语作文初一
关于美术馆的规则英语作文初一Art museums are fascinating places where people can explore and appreciate various forms of art. However, just like any other public space, art museums have certain rules and regulations that visitors need to follow in order to ensure a pleasant and respectful experience for everyone. These rules are in place to protect the artwork, maintain a peaceful environment, and ensure the safety of both the visitors and the exhibits.One of the most fundamental rules in art museums is to refrain from touching the artwork. This rule is crucial as touching the art can cause damage, especially to delicate pieces such as paintings, sculptures, and other fragile items. Even the natural oils on our skin can be harmful to the artwork over time. Therefore, it is important for visitors to admire the art from a distance and resist the temptation to touch or lean on the displays.In addition to refraining from touching the artwork, visitors are also expected to maintain a respectful distance from the exhibits. This meansrefraining from getting too close to the artwork, leaning over barriers, or blocking the view of others. By respecting the personal space of the artwork and other visitors, everyone can have a more enjoyable and enriching experience at the museum.Another important rule in art museums is to refrain from using flash photography. While photography is often permitted in art museums, the use of flash can be damaging to the artwork. The bright light from the flash can cause fading and deterioration of the colors in paintings and other pieces. Therefore, it is important for visitors to be mindful of their surroundings and use only non-flash photography, if allowed.Furthermore, visitors are expected to maintain a quiet and peaceful demeanor while in the museum. This means refraining from loud conversations, using cell phones, or making disruptive noises. By maintaining a tranquil atmosphere,visitors can fully immerse themselves in the beauty of the art and allow others to do the same.Additionally, many art museums have specific rules regarding food and drinks. In order to protect the artwork and maintain a clean environment, visitors aretypically not allowed to bring food or beverages into the galleries. This rule helps to prevent accidental spills or stains on the artwork, as well as to preserve the overall cleanliness of the museum.Finally, it is important for visitors to follow any additional rules or guidelines provided by the museum staff. This may include restrictions on large bags or backpacks, guidelines for visiting special exhibitions, or specific rules for certain areas of the museum. By following these instructions, visitors can help to ensure the safety and security of the museum's collections and facilities.In conclusion, art museums have rules and regulations in place to protect the artwork, maintain a peaceful environment, and ensure the safety of both the visitors and the exhibits. By refraining from touching the artwork, maintaining a respectful distance, avoiding flash photography, and following other guidelines, visitors can contribute to a positive and enriching experience for all. It is important for visitors to be mindful of these rules and to follow them in order to preserve the beauty and integrity of the art for future generations to enjoy.。
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柔性物体的动态等效质量
该结构的弹簧常数
平均水平方向运动的减速（加速）
动态变形
制动路径
减速周期（周期加 速）
振荡系数
静止位置
减速期间振荡的最大振幅
在减速过程中“准静 态”平均的位置
上述微分方程的积分函数
因为到该结构受到的应力成正比的动态变形， 振荡系数 Swmax=2必须用于变形，应力和应力结果的进一步计算。
惯性水平力的影响
使用条件下，稳定性 v 应 ≥1.5; 在特殊
情况下，例如，紧急制动时，应至少 为 1.1
≥ 摩擦力系数
侧向力
取决于加速度的方向，惯性力动态趋于增加或减小车轮荷载
R 1和 R2
额外的负荷分类
缓冲力
特殊负载的分类
为简化计算振荡系数
一般功能测试 紧急捕捞负荷
提升运输赶上或制动 路径
三角图 梯形图 矩形图
FEM9.31存储和检索机器结构设计规则 恒载
超过 弹性极限 材料过度训练 超出 屈曲临界应力 结构过度疲劳
超出 疲劳强度 材料过度训练 许用应力
假定负荷
运行歪斜产生的力
惯性垂直力的影响动， 升降，伸缩
准静态力
由驱动单元产生的水平惯性力 动态振荡系数
对于标注了堆垛机，有必要知道由行驶运动而引起振荡精的确应力。 挠度，应力和压力的 合力应该乘以动态振荡系数 μS
三角形的 梯形
矩形