Computer Ballistics Lab 2

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Introduction to Computers

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© 2001 Paradigm Publishing Inc.
Computer Concepts 1-6
Components of a Computer System
Input Devices
•Keyboard •Mouse •Trห้องสมุดไป่ตู้ckball •Stylus
Shift in information infrastructure
© 2001 Paradigm Publishing Inc.
Computer Concepts 1-4
Progress of Technology through Time
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ENIAC
Composed of 17,000 vacuum tubes, 70,000 resistors, and 10,000 capacitors, the ENIAC (Electronic Numerical Integrator and Computer) weighed over 30 tons and took up 1800 square feet of floor space. Completed in 1945, the ENIAC was used for ballistics work and later on for weather prediction.
Computer Concepts 1-3
The Information Age Timeline
1970’s-1980’s
Infrastructure focused on data crunching and data storage

水中机器人2D仿真水球斯诺克策略优化

ａｎｄｒａｐｉｄ．
Ｋｅｙｗｏｒｄｓ：２Ｄｓｉｍｕｌａｔｉｏｎ；ｒｏｂｏｔｉｃｉｆｓｈ；ｗａｔｅｒｐｏｌｏｓｎｏｏｋｅｒ；ｓｔｒａｔｅｇｙｏｐｔｉｍｉｚａｔｉｏｎ；ａｕｔｏｍａｔｉｃｓｈｉｔ；ｆｈｅａｄｉｎｇｂａｌｌａｌｇｏｒｉｔｈｍ
ｏｐｔｉｍｉｚｅｄｃｏｍｐｅｔｉｔｉｏｎｓｔｒａｔｅｇｙ．Ａｃｃｏｒｄｉｎｇｔｏｔｈｅｓｐｅｅｄａｎｄｃｏｎｓｉｓｔｅｎｃｙ，ｇｉｖｅｓａｎａｕｔｏｍａｔｉｃｓｈｉｔｆｏｆｒｏｂｏｔｉｃｉｓｆｈｈｅａｄｉｎｇ
兵工自动化
ＯｒｄｎａｎｃｅＩｎｄｕｓｔｒｙＡｕｔｏｍａｔｉｏｎ
２Ｏ１３．１２
３２．７６９０／ｂｇｚｄｈ．２０１３．１２．０２２
水中机器人２Ｄ仿真水球斯诺克策略优化
高俊杰，贾翠玲，李卫国
（１．内蒙古工业大学机械学院，呼和浩特０１００５ｌ；２．内蒙古工业大学工程训练中心，呼和浩特０１００５１）
摘要：基于ＵＲＷＰＧＳｉｍ２Ｄ仿真平台，提出一种新型的比赛策略和顶球算法。介绍２Ｄ仿真水球斯诺克现有的比赛策略、顶球算法，给出优化后的比赛策略，根据速度性和连贯性，提出一种自动换挡的机器鱼顶球算法，并以实例对优化后的比赛策略和顶球算法进行仿真实验。实验结果表明：优化后的比赛策略的稳定性有所提高，使顶球更

OpenLabV2用户手册_学生版

（3）超级终端软件的安装和设置
网络实验的全部操作是使用超级终端软件完成，如果客户端没有安装此软件，可按如下方法安装：
“开始菜单” -- “设置” -- “控制面板” -- “添加/删除程序”-- “添加/删除 Windows 组件” -- “附件和工具” -- “通讯”，出现程序列表，请勾选“超级终端”，按“确定”按钮（必要时请播入 Windows 安装光盘.）；并按如下方法设置：
由管理员开设
学生账号
由教师开设
计费用户账号
由管理员开设或实验人员自行注册
管理员可以在其管理目录下的“高级管理”中设定是否开放自行注册的权限，
（详情请参考下章），在开放注册的情况下，计费用户可以点击首页的“注册”按
钮，按照网页的提示填写相关信息，账号和密码只能使用英文字母和数字，不区
P6
e 即易，易则 e
转换到同一拓扑的另一个设备：如果需要配置同一拓扑的其他设备，直接输入该设备的逻辑名，转换到新一个设备的配置状态中；如果您忘记了设备的逻辑名，可以键入指令“<show device>”显示此拓扑的全部设备清单及使用状况；
转换到下一个拓扑实验：退出本超级终端会话窗口，结束超级终端程序。重新回到学生登录后的首页，在“当日实验安排”列表中，点击您新选定的拓扑所在行的“开始实验”按钮。
如果配置正确，IE 浏览器会自动打开超级终端，显示“连接成功”的字样；如果 IE 没有打开超级终端，只显示“请稍等…”的字样，请确认是否安装了超级终端程序，如果已安装，就代表您的电脑没有配置正确，请参考上节介绍的方法重新配置；如果你安装了超级终端软件，并确认按照“配置”的要求进行设置，但进入实验室时还是 Dos 界面的 Telnet 程序而不是超级终端，这时请按以下的方法处理：点击“开始”-“运行”- 键入 Regeidit 打开“注册表编辑器”，把主键值： “ 我的电脑 \HKEY_LOCAL_Machine\Software\classes\telnet\shell\ open\command”的值改为：超级终端安装路径\hypertrm.exe /t %1

Lab 2

Lab 2VelocityOverviewIn this lab, we will explore the relationship between the position function and the velocity function of a moving object. In the lectures, we have seen that the velocity function v(t) is the derivative of the position function s(t) (and therefore s(t) is an antiderivative ofv(t)). We will be examining these statements in this lab by using a motion detector to measure the velocity and position of a person walking.Vocabulary used in this lab•Distance: This is the distance an object is from the motion detector. The words distance and position will be used interchangeably in this lab.•Displacement: This is “change of position,” that is, the difference between the initial and terminal coordinates the object. Displacement can be either positive or negative. (Think about what the difference between positive and negativedisplacement is.)•Velocity and speed: The important thing to note here is that velocity can be either positive or negative, depending on whether motion is in the positive ornegative direction. But speed = |v(t)| is never negative: it is the absolute value of the velocity. For example, a car’s speedometer is measuring speed and alwaysreads positive, regardless of the direction you’re traveling.•Total distance traveled: Perhaps this is best illustrated by an example. If you walk 2 meters forward and then 2 meters backward then your displacement willzero (the initial and terminal positions are the same so therefore the difference of coordinates is zero). But, you actually traveled 4 meters. In this case, the totaldistance traveled would be 4 meters. The “total distance traveled” is nevernegative.Mathematics for this labThe mathematics that we will need is the relationship between displacement and velocity: •Displacement is equal to the definite integral of velocity v(t) over a time interval.•Total distance traveled is equal to the definite integral of speed |v(t)|over a time interval.These ideas are discussed in the textbook on pages 374-375.Materials•Computer with Vernier computer interface.•Vernier motion detector. This will plug into the LoggerPro computer interface.•Separate “Lab Report 2” sheet. This is what you will turn in. It is due one week after your scheduled lab day, by 4:30 pm, in the Mathematics Office (Cupples I,room 100).Comments on the Motion DetectorThe motion detector works by emitting short bursts of ultrasonic sound waves. You will hear a clicking sound when the detector is operating. The detector “listens” for the ech o of these ultrasonic waves returning to it. The motion detector measures the time it takes for the sound waves to make the trip from the detector to the object and back to the detector. Knowing the speed of sound, the detector is then able to calculate the distance to the object.The specifications on the detector state that it has a minimum range of 0.4 m. and a maximum range of 6.0 m. The detector seems to work best if there is a smooth flat surface for the sound waves to bounce off of.Practically speaking, this means that as you collect data•Your motion needs to be parallel to the sensor and not perpendicular to it (i.e., you will need to walk either away from or towards the sensor, or both).•You will probably want to be holding a book or piece of cardboard in the sensor’s “line of sight” while you walk.•If neighboring lab teams are moving while you are collecting data, your motion detector might pick up their motion as well. You will have to cooperate with your neighboring teams so that your motion detector is only picking up data from your walking.•It is very important that the motion detector does not move. (What would the motion detector measure if it was moving?)ProcedureThe first thing to do is get the computer and motion detector ready.Connect the motion detector to the Dig/Sonic 2 port of the Lab Pro. Make sure the Lab Pro is connected to the USB port of the computer. (It is likely that these have already been done for you.)•Set the detector upright on the edge of the desk, facing out in a direction in which you have a clear path at least 2 m. long.•Open the LoggerPro program. You will want to select “Lab Pro USB” for the port in the Setup Interface. It is possible (hopefully not likely) that LoggerProwill not recognize the hardware. If this happens, unplugging the Lab Pro andplugging it back in should take care of the problem.•Open the experiment file for this lab. (Click on the “Open” button and open the file labeled “lab2_velocity.” (It is possible that LoggerPro will complain aboutthis file – just ignore any complaint and click “OK.”)•At this point, you should be able to collect distance and velocity data. Try playing around with the motion detector by pressing the “collect button” on thetoolbar. (For example: turn the sensor to face the nearest wall and collect data—what happens? Turn the sensor around and collect data by moving your handback-and-forth in front of it.) When you start collecting data, notice that velocity and distance data is graphed and the actual data appears in a table to the right ofthe graphs. Notice also that each time you start collecting new data, the data from the previous run is cleared. (Another way to clear recently collected data is toselect Data, Delete Run from the menu.)You are now ready to start collecting data that you will analyze.•Decide who will monitor the computer (and hit the collect button) and who will be the “mover”—the mover will create distance and velocity data bywalking back and forth in front of the motion detector.•Your goal is to generate a data set that exhibits both positive and negative velocity during the five seconds of movement.•There is a limited amount of free space in the lab for straight-line movement, so you will have to coordinate your data collection with your neighbors.Make sure you have a clear path before you start collecting your data.•The mover should take an initial position standing in front of the motion detector, holding a book or a piece of cardboard in the detector’s “line ofsight.” This will help to make a smoother velocity graph as you collect thedata.Before beginning, note the mover’s initial position. When the datacollection stops, the mover should remain in position while his/her partnernotes the terminal position. (An acceptable method to note these positionsis to put a marker, like a pen, on the floor where the mover’s feet start.)Measure and write down these positions (number of meters in front of thesensor); you’ll need this information later. (There will be a tape measurein the lab for you to measure the distances. You’re not looking for greataccuracy—just something in the right ballpark. Remember that 1 meter isapproximately 3.28 feet.).•Click on the “Collect” button and gather the data. When the mover hears the motion detector making the clicking sound, s/he should start moving along astraight line in front of the motion detector. Remember your goal to createdata with positive and negative velocity.After collecting your distance and velocity data, you should make sure your data looks “reasonable”: for example,•Is the graph of the velocity reasonably smooth?•Does the distance data in the table look like what you were expecting? Do the distances more-or-less match up with what you noted for the initial and finalpositions?•Is the velocity positive and negative when you were expecting it to be positive and negative?•If your data looks questionable, collect another set of data. (The good news is that it doesn’t take much time to collect another data set if necessary.) •If your data looks good, save it so that you can finish your report after the lab period if necessary. (If you didn’t bring a diskette, you could e-mail the datato yourself.)At this point, you are ready to analyze your data.•You should have two graphs –position (labeled “Distance vs. Time”) and velocity (labeled “Velocity vs. Time). You should print both of these graphs and also the table: activate each graph or table window before you print (so that youget a nice printout of each one separately).•Click on the “Examine” button (Analyze – Examine in the menu). This should allow you to more easily read both the graph and the data (watch what happenswhen you move the mouse to the graphs and the data table). Using this, answer#1-3 on Lab Report 2.DisplacementWe want to calculate the displacement of the mover after 5 seconds. We can do this in three different ways:a) by having LoggerPro estimate the integral of the velocityfunction v(t) for 0 <= t <= 5b) by using our data and the Fundamental Theorem of Calculus (Part II) to evaluate the same integralc) by using the measurements we made “by hand” during the data collection process.In detail:a) Using LoggerPro to estimate the integral of the velocity:•Click on the left-hand side of the velocity graph (Time=0) and drag the black line across to the right-hand side of the graph. While you are doing this, the values in the table window should be highlighted. Make sure you actually click on thegraph on not outside the graph (otherwise you will see the pop-up box asking you about the y-axis and y-scale).•Click the Integral button or choose Analyze – Integrate from the menu. A floating box with LoggerPro’s estimate of the value of the integral appears in the Veloci ty graph window. Note the units in this box: m/s * s, which is just meters (theseconds cancel out); don’t misread the units as “m/sec2” !! Print a copy of thegraph with the box. Record this value in #4a on the Lab Report.b) According the Fundamental Theorem of Calculus (Part II), we can compute the integral of v(t) over the time interval [0,5] using an antiderivative. In this situation, the numeric result can be worked out using subtracting two numbers taken from your data tables. In the Lab Report #4b state what numbers you are using and give the resulting value for the integral.c) Finally, calculate the displacement using the distances from the sensor that you measured during the data collection process. Record the result of the calculation in Lab Report #4c.In Lab Report #4d, you are asked to offer some reasons why the results in a), b) and c) are (probably) not equal.Total Distance TraveledTo find the total distance traveled, we need to integrate the speed |v(t)| during our 5 second time interval. To have LoggerPro do this,we need the speed data—so we create it in a new column:•Activate the velocity graph window by clicking on the velocity graph. Select View – Graph Options from the menu.•Modify the Graph Title by typing “Speed/” before Velocity. It should now read Speed/Velocity vs. Time. Click Apply, then click OK.•Select Data - New Column, Formula from the Data menu. The New Column window will appear.•Under the Options tab, in the Labels section, type “Speed” for Long Name, “sp”for Short Name and “m/s” for Units.•Click the Definition tab. In the Equation box, enter the formula(abs(“Velocity”)). You can (and should) do this by selecting “abs()” from the Functions list followed by selecting “Velocity” from the Variables list.•Click Try New Column. If it new data looks as it should (how should it look?), then click “OK”.•Notice that the new graph (Speed) coincides with the original velocity graph when the velocity is positive. How do these graphs compare when velocity is negative? •Click on the left-hand side of the speed/velocity graph (Time = 0) and drag the black line across to the right-hand side of the graph. All of the values in the table window should be highlighted.•Click the Integrate button. An Integral Selection window appears. Remove the check next to Velocity by clicking in its box. Make sure that Speed is checked.Click OK.• A floating box with LoggerPro’s estimate of the value of the integral appears in the Speed/Velocity graph window. Print a copy of the graph with the box. Report the total distance traveled on Lab Report, #5.Answer #6 and #7 on the Lab Report sheet.。

Pearson Edexcel Level 2 编程设计与应用Unit 1 开发网页产品P4828

Paper ReferenceTurn over Instructions•Complete all activities.•You must not use the internet during this test.Information•There is ONE task in this examination paper, containing TWO activities.•T he ASSETS folder in your user area includes all the content and informationyou need.•The invigilator will tell you where to store your work.•You may use blank paper for design work.•The total mark is 50.•T he marks for each activity are shown in brackets– use this as a guide as to how much time to spend on each activity.Advice•Read the task and instructions on pages 2–4.•Save your work regularly.•Check your work.You must have: A computer workstation, appropriate software,ASSETS folder containing data files and EVALUATION.doc,blank paper for design workPearson Edexcel Level 2*P48284A*P48284A©2017 Pearson Education Ltd.1/1/1DA201/019 January – 13 January 2017Time: 2 hours 30 minutesCertificate in Digital ApplicationsUnit 1: Developing Web Products2P48284ACLIENT BRIEFImpromptoo is a pop-up, temporary music shop. Impromptoo will be trading in Crawdale High Street for three days. The shop will sell a wide variety of music on vinyl and CD and feature a different local DJ every day.Impromptoo wants you to produce a microsite to attract customers to the shop. The target audience is local people, who are interested in buying, making and listening to music.The basis for the content and information for the microsite can be found in the ASSETS folder.Overall site requirements• Four pages: • home page, linking to • merchandise page • music page • DJ page.• Content must be visible, without scrolling, at a resolution of 1024 x 768 pixels.• Facts about Impromptoo , which should be taken from the INFO.rtf file. This text may be edited.• Images to be taken from the ASSETS folder, which may be edited.• Accessibility features for visually impaired users.• A consistent design across the microsite.Other requirementsPage template A banner including a suitable image and the shop logo. The banner should extend the full width of the page.The shop logo should be linked to A navigation bar linking to the home, music and DJ pages.The navigation bar should include the home, music and DJ icons as part of the links.The shop logo, images and icons can be found in the IMAGES folder.Page title Include a suitable title on each page. Each title should relate to the page content.File formats Images to be in .png format and each individual image must be less than 450 KB.All the audio files should be in .mp3 format.3P48284A Turn overShopfrontThe image SHOPFRONT.jpg can be found in the IMAGES folder:• edit the image to include the shop name • include the edited image on the home page.T-shirt hotspot Include T-SHIRT.png on the home page.Add a hotspot over the t-shirt to create a link to the merchandise page. The hotspot should be the same shape as the t-shirt.PlaylistThe client has given you the following sketch.Using the sketch as a guide, create a box for a playlist on the music page:• t he box should have a background colour of #cc3333 and a 1px solid black border• i nclude the three record cover images – RECORD_ONE.png, RECORD_TWO.png and RECORD_THREE.png• include the name of each record to the right of its cover• use an <h4> tag for the name of each record• under the name, embed the audio for each record• the audio should play only on click. The record cover images can be found in the IMAGES folder. The record names can be found in the INFO.rtf file. The audio files can be found in the ASSETS folder.Flyer Convert the image FLYER.jpg to the required format and insert it on any page. FLYER.jpg can be found in the IMAGES folder.Local DJs From the LOCAL_DJs.png image, choose one DJ to create a graphical link on the DJ page that:• shows only your chosen DJ• links to an image showing all the DJs.The LOCAL_DJs.png image can be found in the IMAGES folder.Contacts Add an email link on the merchandise page. The email address can be found in the INFO.rtf file.4P48284A THE TASKYou must design and create a microsite for Impromptoo .You will need to create a page template to ensure consistency.You must include the requirements specified in the client brief.You should create a logical folder structure for your site files.In Activity 2, you will need to explain your design decisions, justify your choices and suggest further improvements as part of your evaluation.Activity 1Design, build and test the microsite.(44)Activity 2Complete an evaluation of your microsite using the document EVALUATION.doc (6)(Total for Task = 50 marks)TOTAL FOR PAPER = 50 MARKS。

今日新鲜事计算机高级应用(二级)课程

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文档下载后可定制随意修改，请根据实际需要进行相应的调整和使用，谢谢!并且，本店铺为大家提供各种各样类型的实用资料，如教育随笔、日记赏析、句子摘抄、古诗大全、经典美文、话题作文、工作总结、词语解析、文案摘录、其他资料等等，如想了解不同资料格式和写法，敬请关注!Download tips: This document is carefully compiled by the editor. I hope that after you download them, they can help you solve practical problems. The document can be customized and modified after downloading, please adjust and use it according to actual needs, thank you!In addition, our shop provides you with various types of practical materials, such as educational essays, diary appreciation, sentence excerpts, ancient poems, classic articles, topic composition, work summary, word parsing, copy excerpts, other materials and so on, want to know different data formats and writing methods, please pay attention!今日新鲜事计算机高级应用(二级)课程随着科技的发展，计算机高级应用课程变得越来越受到重视。

深入理解计算机系统LAB2

深入理解计算机系统ＬAB2————————————————————————————————作者: ————————————————————————————————日期：LAＢ1实验报告实验目的:使用课程知识拆除一个“Biｎary Bomｂs”来增强对程序的机器级表示、汇编语言、调试器和逆向工程等理解。

实验简介:ﻩ一个“BｉnａrｙBombs”(二进制炸弹，简称炸弹）是一个Ｌinuｘ可执行C程序,包含phase1～phase6共6个阶段。

炸弹运行各阶段要求输入一个字符串,若输入符合程序预期，该阶段炸弹被“拆除”,否则“爆炸”。

实验目标是你需要拆除尽可能多的炸弹。

运行结果:ﻩ通关密码储存在001３1．ｔｘt文件中。

成功运行结果截图：ﻩ实验中的六组密码：PＨASＥ1:字符串比较ﻩ本关比较简单，根据课件中的提示用GDB将最先压栈的那个字符串常量打印出来，然后将其作为密码输入，比较成功后即通关。

08048ab2 <ｐhasｅ_1>:８04８ab２：ﻩ8３ｅc 14 sｕb $0x14，%eｓp804８ab5：6ﻩ８ 0４９f 04 ０8 push ＄０x804９f04804８aｂa：ﻩff 74 ２4 １c ﻩpusｈｌ 0ｘ１c(%esp)804８aｂe：ﻩe8 4d 04 00 00 ﻩcalｌ 8048f10 <ｓtrings_noｔ_equaｌ> ﻩ将地址0ｘ8049f０4中的值打印出来：即“The future wｉll be ｂetｔｅｒtomorrow．”PＨＡSE2：循环在查看汇编语言的时候,会看到有调用一个read_sｉx＿number函数，猜测此题是让输入六个数字。

08048ad3 ＜phaｓe_2>:8048aｄ３：ﻩ５6 ｐusｈ％esi53ｐuｓh %ebx8048aｄ4:ﻩ83 eｃ2c ﻩsub $0x2c,％ｅｓｐ804８ad５：ﻩ80４8ad8: 8d ４4 24 1０lea 0x10(％eｓp）,％eａx80４８adc:ﻩ50pusｈ %eax8０48ａdｄ:ﻩfｆ 74 ２４３c ﻩｐｕshｌ0ｘ3c（%esｐ）8048aｅ1：e8 ４6 05 ０0 00 calｌ８0490２c <reａd_ｓix_numbers>83ｃ４１０ａdd ＄0x10，%ｅsp８04８ａｅ6:ﻩ8０４8ae9:ﻩ８3 ７ｃ２4 0８０１ﻩcmｐl $0x1，0ｘ8（%esp)-－－-－-→判定是否为18048aee: ７4 1ｅﻩje 8048b0ｅ <phaｓe＿2＋0x3b>8０48af0: e8 1２０5 00 00 ﻩｃall 8049007 <explｏde＿boｍb>8048aｆ5: eｂ 17 jmp 8０48b０e <phasｅ_２+０x3ｂ>80４８af７:ﻩ８b ０3 ﻩmov (%ebx）,%eａx８04８aｆ9:0ﻩ１ c0 ﻩａｄd %ｅax,%eax－---→进行自加,扩大两倍8０48afb: 39 43 04 ﻩcmp %eax，0x４(%ebx）0５ｊe ８0４８b05 <ｐhasｅ_2+0x３74８048ａfｅ:ﻩ2>8048b００:ﻩｅ8 02 05 ０0 00 call ８049007 <ｅｘplode_bｏmb> 83c3 ０4 add $０x4,％ｅｂｘ8０48b05:ﻩ8048b08: 39 f３ﻩｃmp %eｓi,%ｅbx8048ｂ0a：7５ｅb ﻩjｎｅ８０48ａf7 ＜phａsｅ_2＋0ｘ24＞8０４８b0ｃ: eb 0a ｊｍｐ８０48b18 ＜phaｓｅ_2+０ｘ４５＞８0４8b0e:ﻩ8d 5c 24 08 lｅa 0ｘ8（％esｐ），%ｅｂx８048ｂ12：ﻩ８ｄ 7４2４ 1c ﻩleａ 0x１c（%eｓp),％ｅsi8048b1６: eb df ｊmp 8048ａf7 <phaｓe_２+０x24>→循环8０48b18：83 c4 ２4 ﻩadd $０x２4,％eｓp80４8b1b:ﻩ５b pop %ebx８04８b1c: 5e ﻩpop %esi804８ｂ1d：ﻩc3 ﻩrｅt有汇编语言进行分析,不难看出，这道题目要求输入六个数字,并且要求第一个数字为1，之后跳入一个循环，将第一个数字加倍和已有的数字进行比较，所以不难看出所需要的密码是1,２,4,8,16,32这六个数字。

深入理解计算机系统LAB2

实验二报告一、实验内容根据实验文件里的提示，补充15段代码，熟悉对整型和浮点型数的操作，并成功调试运行。

二、实验程序解释1.bitAnd要求只运用~和|符号实现and的功能。

a and b=not(not a or not b),根据德摩根律易得结果。

int bitAnd(int x, int y) {return ~(~x|~y);}2.getByte得到x的第n个字节的值，规定其中x的最低位为第0个字节，最高位为第3个字节。

如果是第0个字节，将x右移0个字节再利用掩码0xFF将高位的三个字节置为0。

如果是求第1个字节，将x右移1个字节，同理利用掩码。

可以知道，将x右移n个字节也就是n*8位、即(n<<3)位。

接下来清除前三个高位字节，保留最低字节的信息，与0xFF进行&运算。

int getByte(int x, int n) {int t;t=x>>(n<<3);t=t&0xFF;return t;}3.LogicalShift逻辑右移是将移动后补充的高位置0，而算数右移时补充的和符号位相同。

对于字x，需要进行逻辑右移n位。

将x用sxxxxxxx表示，s为符号位，算术右移n-1位的结果为ss…sxx..（有n个s）。

想要得到的结果是00…xxx..(n个0)，所以如果能得到s’s’…s’111..（n个s’）的话，按位与就能得到结果。

首先提取符号位t，1左移31位得到100..00，与x进行按位与操作得到s000..0，接着算术右移n位，得到ss..s00..00（n+1个s），再左移1位，得到s..s0..0(n个s)，取反得到s’s’..s’111..1。

这样就能得到逻辑右移n位的结果了。

注意，在得到s’s’…111的过程中，不能直接将s00.. 0右移n-1位，考虑特殊情况，n为0时，右移-1位是不正确的。

int logicalShift(int x, int n) {int t=(1<<31)&x;t=~((t>>n)<<1);t=(x>>n)&t;return t;}4.bitCount要求计算32位二进制数x中1个个数。

简单保龄球游戏编程

简单保龄球游戏编程在开始介绍简单保龄球游戏的编程之前，我们先来了解一下保龄球游戏的规则和基本要素。

保龄球是一种室内运动，通常由两支球队进行比赛，每支球队有2-6名球员。

每位球员轮流进行投球，并且试图将球击倒10个排列成三角形的瓶子。

每轮投球结束后，倒下的瓶子会被重新摆放。

根据倒下的瓶子数量来计分，而最高得分的球队将获胜。

保龄球游戏编程可以通过使用编程语言和相关的开发工具来实现。

最常用的编程语言之一是C++，它具有强大的图形和计算能力，非常适合用于保龄球游戏的编程开发。

接下来，我们将使用C++来编写一个简单的保龄球游戏。

首先，我们需要创建一个保龄球游戏的窗口界面。

可以使用相关的图形库来实现，例如使用OpenGL来绘制游戏界面。

在游戏界面中，我们可以绘制保龄球的球道和瓶子，以及指示球的路径等元素。

同时，还需要实现一些用户交互功能，例如按下空格键来发球，按下方向键来控制球的移动方向等。

接下来，我们需要编写保龄球球道的物理模拟和碰撞检测等功能。

球道可以看作是一个斜坡，球在滚动过程中受到重力的作用，并具有一定的摩擦力。

为了检测球和瓶子之间的碰撞，我们需要计算球的位置和速度，以及瓶子的位置和状态。

当球撞击到瓶子时，需要判断球的移动方向和速度，以及瓶子的倒下状态，并根据相应的规则进行计分。

此外，我们还可以添加一些其他功能来增加游戏的趣味性，例如在球道上放置一些障碍物，或者实现不同难度级别的模式等。

可以根据需要自行设计和开发。

总结一下，编写简单保龄球游戏的编程需要掌握C++编程语言和相关的图形库，并具备一定的物理模拟和碰撞检测等知识。

通过合理设计和编程实现，可以创建一个美观、流畅，并且具有一定趣味性的保龄球游戏。

希望以上的介绍对您有所帮助，祝您编写保龄球游戏的编程开发顺利！。

计算机图形学二维弹球实验报告

计算机图形学实验报告实验一、二维弹球游戏设计一、实验目的与基本要求：（1）掌握在VS2010或以上版本环境下如何配置OpenGL环境的方法；（2）熟悉OpenGL应用程序基本架构；（3）培养良好的编程习惯和风格，学习撰写实验报告；（4）学习交互式游戏设计；（5）通过小球移动、反弹、击中等功能实现学习二维几何的基本运算；（6）菜单的使用。

二、实验设备（环境）及要求1. 操作系统：Windows XP 或Windows 72. 编程环境：Microsoft Visual Studio 2010，OpenGL 库函数3. 界面框架：Win32，MFC，QT选择其中一种三、实验内容与步骤实验分为以下几个步骤：1.绘制游戏界面和基础物体（小球、挡板）2.实现小球的发射及方向的控制3.实现小球与墙壁和挡板、挡板与墙壁的碰撞算法4.实现键盘控制的挡板移动5.菜单游戏介绍及难度等级的选择附加功能：1.砖块的绘制和与小球的碰撞2.砖块的消失3.文字标识的游戏的输赢4.增加了小球的生命数以及血量条5.增加了背景图案的变化和背景颜色的切换四、实现过程说明及成果展示：1.绘制游戏界面和基础物体（小球、挡板）游戏界面的绘制使用画面单位的长和宽与画面比例相乘得到小球的绘制和挡板的绘制函数为运用了绘制小球2.实现小球的发射和方向控制小球的初始方向设置为向量（1,1）的方向，其x轴和y轴的方向分别用数组分开存储：ballDir[0]表示x轴，ballDir[1]表示y轴3.实现小球与墙壁和挡板、挡板与墙壁的碰撞算法小球与墙壁的碰撞和挡板相似，以挡板为例：小球的坐标处设置为球心坐标，故其与挡板的碰撞位置判断时需要加上小球的半径当小球与挡板的上部碰撞时：小球位置应在挡板的左右横坐标之间，当小球球心位置+ 小球半径< 挡板上沿并且小球位置> 挡板下沿（保证球不会穿过挡板）时，小球的则不能继续穿过挡板，（为了实现小球镜面反射式的碰撞）则小球的水平速度不变，竖直速度反向，实现代码如下：对比以上方式，小球与挡板侧面发生碰撞时，只需小球的竖直速度不变，水平速度反向即可。

attacklab实验总结 -回复

attacklab实验总结-回复Attacklab实验总结Attacklab实验是一项旨在让学生深入了解计算机系统底层原理和安全性的实践性课程。

通过该实验，学生能够亲自实践漏洞利用和防御的技术，提高对计算机系统安全性的认识和理解。

本文将从实验流程、实验内容和实验收获三个方面回答关于Attacklab实验的问题。

一、实验流程Attacklab实验包括三个实验阶段：Phase1、Phase2和Phase3。

Phase1：Buffer LabPhase1是Attacklab实验的入门阶段，目的是让学生了解栈缓冲区溢出的原理和利用方式。

学生需要分析给定的源代码，在栈上分配合适的空间，并使用合适的输入来修改程序执行路径，达到改变程序行为的效果。

Phase2：Return-Oriented Programming LabPhase2是Attacklab实验的进阶阶段，目的是让学生了解ROP （Return-Oriented Programming）的原理和利用方式。

学生需要找到程序中合适的代码片段（称为gadgets），通过串联这些gadgets来实现攻击。

与Phase1相比，Phase2更加复杂和技术性，需要学生在程序的内存空间中构建复杂的ROP链。

Phase3：Code-Injection Attacks LabPhase3是Attacklab实验的高级阶段，目的是让学生了解代码注入攻击的实现原理。

学生需要通过构造合适的输入，将恶意代码注入到程序执行的内存空间中，并实现自己的攻击目标。

二、实验内容1. Buffer Lab在Buffer Lab中，学生需要完成五个不同的任务，每个任务都涉及到栈溢出攻击的不同方面。

通过这些任务，学生可以熟悉栈帧布局、溢出点的定位和栈溢出攻击的基本原理。

2. Return-Oriented Programming Lab在ROP Lab中，学生需要构建复杂的ROP链，以利用程序中的存在漏洞的函数。

Lab 2 Stereographic Projection

Techniques of plotting---plotting a plane with attitude 120 30
P: tracing paper, m: Wulff net
Plotting the plane: 30 45
• 1. Count 30°from point N clockwise, get point “A” • 2. Rotate the tracing paper and make point “A” superposition with “E”. • 3. Count 45°from “A”alone A—O, and get point B. • 4. Draw the longitude great circle passing point B. • 5. Revert the tracing paper, the great circle represents the plane 30 45
R
S
Statistics with Schmidt net
Center counter
Peripheral counter
Contouring
Assignment
Please solve the following problems 1. Plot the following planes on the stereonet: a) 245 30, b) 20 60 , c) 340 40 ,d) 120 70 2. Plot the following lines on the stereonet: a) 42 - 62 , b) 130 - 45, c)220 - 50, d) 315 - 32 3. Plot the following poles (or, normals) to the planes on the stereonet: a) 318 26 , b) 125 35 , c) 338 15 4. Find the attitude of the intersection line between two planes: 245 30 and 145 48 5. Find the apparent dip in a direction of 80, 190 individually, on the plane oriented 154 40 .

普林斯顿计算机公开课(原书第2版)

第8章络
第10章万维
8.1与调制解调器 8.2有线电视和DSL 8.3局域和以太 8.4无线络 8.5手机 8.6带宽 8.7压缩 8.8错误检测与纠正 8.9小结
9.1互联概述 9.2域名和 9.3路由 9.4 TCP/IP 9.5高层协议 9.7物联 9.8小结
10.1万维是如何工作的 10.2 HTML 10.3 cookie 10.4动态页 10.5页之外的动态内容 10.6病毒、蠕虫和木马 10.7 Web安全 10.8自我防御 10.9小结
普林斯顿计算机公开课（原书第2版）
读书笔记模板
01 思维导图
03 目录分析 05 精彩摘录
目录
02 内容摘要 04 读书笔记 06 作者介绍
思维导图

本书关键字分析思维导图
技术
语言
第版
工作
计算机
课程
硬件
公开课
世界
计算机小结
编程
普林斯顿
第章
字节
软件
部分
信息
程序
内容摘要
从1999年开始，作者在普林斯顿大学开设了一门名为“我们世界中的计算机”的课程（COS 109： Computers in Our World），这门课向非计算机专业的学生介绍计算机的基本常识，多年来大受学生追捧。本书就是基于这门课程的讲义编写而成的，书中不仅解释了计算机和通信系统的工作原理，还分析了新技术带来的隐私和安全问题。第2版的新增章节讨论了Python编程、人工智能、机器学习以及大数据等内容。本书适合所有希望了解数字世界的读者阅读，通过了解技术的工作原理、起源和未来发展趋势，更好地理解并改变我们身处的世界。
第5章编程与编程语言
第4章算法

往年catics2d试题

往年catics2d试题往年的CATICs2D试题涵盖了计算机科学与技术的各个方面，包括编程、数据结构、算法、操作系统、计算机网络、数据库等。

以下是一些可能出现在CATICs2D试题中的题目类型和内容：1. 编程题，要求编写特定功能的程序或算法。

可能涉及各种编程语言，如C、C++、Java、Python等。

题目可能涉及字符串处理、数组操作、递归、排序算法、查找算法等。

2. 数据结构题，要求设计和实现特定的数据结构，如链表、栈、队列、树、图等。

可能涉及数据结构的基本操作、遍历、查找、插入、删除等。

3. 算法题，要求设计和实现特定的算法，如动态规划、贪心算法、回溯算法、图算法等。

可能涉及最短路径问题、最小生成树、拓扑排序、背包问题等。

4. 操作系统题，涉及操作系统的基本概念、进程管理、内存管理、文件系统等。

可能涉及进程调度算法、死锁处理、内存分配算法、文件操作等。

5. 计算机网络题，涉及计算机网络的基本概念、网络协议、网络安全等。

可能涉及IP地址分配、路由算法、传输层协议、网络安全技术等。

6. 数据库题，涉及数据库的基本概念、SQL查询、事务管理等。

可能涉及表设计、查询优化、事务隔离级别、数据库索引等。

在回答这些试题时，需要考虑以下几个方面：1. 理论知识，回答试题需要掌握相关的理论知识，包括算法、数据结构、操作系统、计算机网络、数据库等方面的知识。

2. 实际应用，试题可能会涉及实际应用场景，需要结合实际情况进行分析和解答。

3. 举例说明，为了更好地解释问题，可以举例说明，以帮助读者理解。

4. 思路清晰，回答问题时需要有清晰的思路，可以先分析问题，然后给出解决方案，最后给出具体的实现步骤。

总的来说，往年的CATICs2D试题涵盖了计算机科学与技术的各个方面，需要综合运用所学的知识和技能来解答问题。

希望以上回答能够满足你的要求。

MATLAB数学建模2乒乓球的弹跳和罗基斯帝模型

乒乓球的弹跳罗基斯第模型[问题]罗基斯第模型一个乒乓球离球拍的高度为h0，落在球拍上反弹，设恢复系数为e，不计空气阻力。

(1)如果e为常数，讨论球的高度变化的规律。

如果e2与高度h n成线性关系e2=μ(1–h n/H0)(2.1) 其中H0是最大高度，μ是参数。

对于不同的参数讨论小球高度的变化规律。

(2)当参数连续变化时，分析最后分布的高度。

(3)计算前几个分岔点。

(4)用李雅普洛夫指数判断混沌的发生。

[解析](1)当球从高度h n下落到球拍上之前速度为vn球与球拍碰撞后反弹的速度为v'n=ev n(2.3) 球反弹的高度为h n+1=e2h n(2.4) 如果e<1，则球的反弹高度随次数不断减小；如果e=1，则球反弹后始终保持初始高度；如果e>1，例如球拍每次加一个向上的冲击力，则球的高度随次数不断增加。

e2与高度的线性关系说明：如果球的高度较大，则恢复系数较小，反之较大。

设相对高度为x n=h n/H0，则下一次上升的相对高度为x n+1=μ(1–x n)x n，(n=0,1,2,…)(2.5) 这是着名的罗基斯第模型。

由于相对高度0≤x n≤1，而(1–x n)x n 的最大值为1/4，所以参数的值在0到4之间。

球的高度强烈依赖参数。

[算法](1)先取一个参数，再取一个相对高度，通过迭代算法计算下一次碰撞后的高度，画出高度点，依此类推。

再取另一高度参数，重新通过迭代算法计算高度，画出高度点，依此类推。

[程序]MATH2_1.m如下。

%乒乓球与球拍的碰撞高度clear%清除变量u=input('请输参数(参考值:0.5,2,3.25,3.5,3.56,3.8):');%键盘输入初始相对高度(1)xn=0.9;%第1个的初始相对高度(2)figure%开创图形窗口plot(0,xn,'.')%画高度点text(0,xn,num2str(xn),'FontSize',16)%标记第1个的初始高度grid minor%加细网格title(['乒乓球与球拍的碰撞高度(\it\mu\rm=',num2str(u),')'],'FontSize',16)%标题n=50;%迭代次数axis([0,n,0,1])%坐标范围hold on%保持图像for j=1:n%按次数循环xn=u*(1-xn)*xn;%计算下一次的相对高度(3)plot(j,xn,'.')%画高度点end%结束循环xn=0.1;%取初始相对高度(4)plot(0,xn,'ro')%画高度点text(0,xn,num2str(xn),'FontSize',16)%初始高度for j=1:n%按次数循环xn=u*(1-xn)*xn;%计算下一次的相对高度(5)plot(j,xn,'ro')%画高度点end%结束循环[说明](1)程序执行时要用户用键盘输入参数，提供6个参数选择。

MIT6.824spring21Lab2D总结记录

MIT6.824spring21Lab2D总结记录写在前⾯lab2D是今年新添加的部分，⽹上很难找到博客资源。

这⼀部分要求我们为raft添加log compaction功能：在运⾏⼀段时间后，raft的上层service可以⽣成⼀个snapshot，并通知raft。

在这之后，raft就可以丢弃snapshot包含的log entries，起到节约空间的作⽤。

这部分难度不⼤，但是细节略多。

（测试结果：Lab2D的testcase跑50次，全部PASS）代码见：https:///sun-lingyu/MIT6.824-spring21/tree/Raft-2D关于CondInstallSnapshot看过Lab2D实验指导的⼈都会发现，如果follower收到了⼀个InstallSnapshot RPC，其处理逻辑是⾮常扭曲的：⾸先，在InstallSnapshot Handler中，follower需要将收到的snapshot通过applyCh发送给上层service。

此时follower并不会安装这个snapshot。

在⼀段时间后，上层service会调⽤CondInstallSnapshot函数，询问raft是否应该安装此snapshot。

若在follower执⾏InstallSnapshot Handler 到执⾏CondInstallSnapshot的这段时间⾥，raft没有因为收到applyentries RPC导致其commitID超过该snapshot。

在什么情况下CondInstallSnapshot会拒绝安装snapshot？当然，出现“CondInstallSnapshot拒绝安装snapshot”这种情况，是可以理解的。

下⾯给出⼀种可能的情况：leader的当前状态如下。

图中的直线代表leader的log，且假设所有的log entry都已commit。

leader向其中⼀个落后的follower发送appendEntries RPC。

ballistics 小节

BallisticsBallistics is the branch of science that deals with the motion of projectiles, such as bullets, rockets, and artillery shells. It involves the study of the forces acting on these projectiles, their trajectory, and their impact.History of BallisticsThe study of ballistics dates back centuries. In ancient times, it was primarily focused on the development of weapons and their effectiveness on the battlefield. However, with the advancement of technology, ballistics has evolved into a scientific discipline with various applications in fields such as forensic science, astronomy, and aerospace engineering.Internal BallisticsInternal ballistics refers to the study of the behavior of a projectile within a firearm or other launching device. It involves the study of propellants, their combustion, and the pressure generated inside the gun barrel. Internal ballistics is crucial in ensuring the safe and efficient functioning of firearms.External BallisticsExternal ballistics deals with the behavior of a projectile after it has left the barrel. It focuses on the projectile’s flight path, which is influenced by factors such as air resistance, gravity, wind, and spin. External ballistics is essential in accurately predicting a projectile’s tr ajectory and determining its range and impact.Terminal BallisticsTerminal ballistics involves the study of how projectiles interact with the target upon impact. It includes the analysis of factors like penetration, expansion, fragmentation, and energy transfer. Terminal ballistics helps determine the effectiveness of projectiles in various applications, including hunting, self-defense, and military operations.Forensic BallisticsForensic ballistics applies the principles of ballistics to legal investigations. It involves the analysis of firearms, ammunition, and bullet trajectories to determine crucial details in criminal cases. Forensic ballistics helps identify the weapon used, establish the distance between the shooter and the victim, and reconstruct the events of a crime scene.Applied BallisticsApplied ballistics utilizes the principles of ballistics to optimize the performance of projectiles. It involves the use of mathematical models, computer simulations, and experimental data to design projectiles with enhanced accuracy and effectiveness. Applied ballistics is particularly important in military applications and long-range shooting.Ballistic ProtectionBallistic protection focuses on the development of materials and structures capable of resisting the penetration of projectiles. This field is essential for personal protective equipment such as bulletproof vests and helmets. Ballistic protection research aims to enhance the safety and survivability of individuals in high-risk environments.ConclusionBallistics is a multidisciplinary field that intersects various scientific disciplines, engineering, and law enforcement. Its applications range from improving weapon technology to analyzing crime scenes and protecting individuals. By understanding the principles of ballistics, we can enhance safety, accuracy, and effectiveness in various domains.。

大连理工版信息技术五年级下册《趣味弹力球》课堂练习附课文知识点

大连理工版信息技术五年级下册《趣味弹力球》课堂练习附课文知识点课文知识点归纳：1. 弹力球游戏的基本规则和操作方法。

2. 计算机程序中的条件判断和事件响应原理。

3. 通过游戏理解物理中的弹力和动量概念。

4. 学习使用编程软件（如Scratch）设计简单游戏。

5. 培养问题解决和逻辑思维能力。

课堂练习：一、判断题：1. 在《趣味弹力球》游戏中，球只会向斜上方弹跳。

（）2. 游戏中的弹力球在碰到障碍物时会改变方向，这是通过编程中的条件语句实现的。

（）3. 设计弹力球游戏时，我们不需要考虑物理中的弹力和动量。

（）二、选择题：1. 在编程中，如何让弹力球在碰到边缘时自动反弹？A. 使用"如果...那么..."的条件语句B. 设定球的移动速度为零C. 直接改变球的运动方向D. 无需处理，游戏会自动实现2. 下列哪个概念与弹力球游戏的物理效果无关？A. 重力B. 动能C. 速度D. 数据分析3. 在Scratch中，如何让弹力球在屏幕上移动？A. 使用"移动10步"的积木B. 设定球的旋转速度C. 通过"广播"和"接收"实现D. 直接输入数学公式三、填空题：1. 弹力球在碰到障碍物后，会根据______和______改变运动方向。

2. 在Scratch中，我们通常使用______积木来检测弹力球是否碰到边界或障碍物。

四、简答题：1. 解释一下在编程中，"如果...那么..."的条件语句是如何工作的，以及它在弹力球游戏中是如何应用的。

2. 请描述一下弹力球游戏是如何体现物理中的弹力和动量概念的。

参考答案：一、判断题1参考答案：错误，球的弹跳方向取决于碰撞的角度和力度。

2参考答案：正确3参考答案：错误，这些因素会影响游戏的趣味性和真实性。

二、选择题1（参考答案：A）2（参考答案：D）3（参考答案：A）三、填空题1（参考答案：碰撞力度，碰撞角度）2（参考答案："如果碰到...那么..."）四、简答题1（参考答案："如果...那么..."语句用于设定一个条件，当这个条件满足时，程序会执行特定的操作。

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Computer Ballistics Lab #2 Name________________________________1. Go to the PHET web site/web-pages/simulations-base.htmlGo to the Motion Page and start the Projectile Motion simulation.2. Try using some of the different objects in the pull down menu without air resistance.3. Now try the different objects with air resistance.4. What do you notice about all of the projectiles when there is no air resistance?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 5. What does air resistance do to a projectile? Why?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 6. Why does a bowling ball go farther than a golf ball even though a golf ball has a much smaller drag coefficient?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 7. Why does a human go so much farther than a Buick when they have the same drag coefficient?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 8. What things are important to know in order to find out how an objects path will be changed by air resistance?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 9. Move the target to a distance 20 meters from the cannon. With air resistance off and10. Which angle requires the fastest speed in order to hit the target? Why?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________11. Which angle requires the slowest speed to hit the target? Why?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________12. What do you notice about angles 75° and 15°?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________13. If an X appears on the trajectory at each second how long was each shot up in the air? Which shot was in the air the longest?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________14. How did the shots with the smallest angles go just as far as the shots that were in the air the longest?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________15. Using the magnifying glass move the target to 490 meters. For the golf ball with no air resistance fire a shot with Angle 45° and Initial Speed 69.3 m/sec. This is Trajectory A.Without erasing fire a shot with Angle 75° and Initial Speed of 50.7 m/sec. This is Trajectory B.These two shapes are called parabolas. Notice the X that appears at each second—the highest point for each parabola is at 5 seconds. This is called the vertex.Using the tape measure; measure the height of each vertex and the length of each trajectory.16. Why do the X’s get closer together as you get to the top of the parabola?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 17. What happens to the speed of the golf ball as you get closer to the top of the parabola? Does the horizontal speed change or only the vertical speed?________________________________________________________________________ ________________________________________________________________________trajectory has the highest total speed? How can you tell?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 19. On the same screen fire a shot at Angle 75° and Initial Speed 97.9 m/sec. Call this Trajectory C. Find the:Vertex (m)=______ Horizontal Trajectory (m) =______ Duration (seconds in air) = ____ 20. How does trajectory C compare to Trajectory A and Trajectory B?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 21. What is the horizontal speed of Trajectory C? _____________ What is the vertical speed of Trajectory C? ____________ Which of the three trajectories has the highest initial speed? __________ Which of the three trajectories has the highest speed at the vertex?______22. Shoot trajectories C again looking carefully at the data readout at the top of the window. Using the range and time readout find the horizontal speed at second five. How does this compare to the horizontal velocity calculated in problem 21? Explain.________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 23. Using the vertex height and the second marks find the average vertical velocity of the golf ball as it goes to the top of trajectories A, B and C. How does this compare to its actual (instantaneous) vertical velocity at the vertex?________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________。