建筑外文文献及翻译

建筑外文文献及翻译
外文原文
Study on Human Resource Allocation in Multi-Project Based on the Priority and the Cost of Projects
Lin Jingjing , Zhou Guohua
SchoolofEconomics and management, Southwest Jiao tong University ,610031 ,China
Abstract----This paper put forward the a ffecting factors of project’s priority. which is introduced into a multi-objective optimization model for human resource allocation in multi-project environment . The objectives of the model were the minimum cost loss due to the delay of the time limit of the projects and the minimum delay of the project with the highest priority .Then a Genetic Algorithm to solve the model was introduced. Finally, a numerical example was used to testify the feasibility of the model and the algorithm.
Index Terms—Genetic Algorithm, Human Resource Allocation, Multi-project’s project’s priority .
1.INTRODUCTION
More and more enterprises are facing the challenge of multi-project management, which has been the focus among researches on project management. In multi-project environment ,the share are competition of resources such as capital , time and human resources often occur .Therefore , it’s critical to schedule projects in order to
satisfy the different resource demands and to shorten the projects’ duration time with resources constrained ,as in [1].For many enterprises ,the human resources are the most precious asset .So enterprises should reasonably and effectively allocate
each resource , especially the human resource ,in order to shorten the time and cost of projects and to increase the benefits .Some literatures have discussed the resource allocation problem in multi-project environment with resources constrained. Reference [1] designed an iterative algorithm and proposed a mathematical model of the resource-constrained multi-project scheduling .Based on work breakdown structure (WBS) and Dantzig-Wolfe decomposition method ,a feasible multi-project planning method was illustrated , as in [2] . References [3,4] discussed the resource-constrained project scheduling based on Branch Delimitation method .Reference [5] put forward the framework of human resource allocation in multi-project in Long-term ,medium-term and short-term as well as research and development(R&D) environment .Based on GPSS language, simulation model of resou rces allocation was built to get the project’s duration time and resources distribution, as in [6]. Reference [7] solved the engineering project’s resources optimization problem using Genetic Algorithms. These literatures reasonably optimized resources allocation in multi-project, but all had the same prerequisite that
the project’s importance is the same to each other .This paper will analyze the effects of project’s priority on human resource allocation ,which is to be introduced into a mathematical model ;finally ,a Genetic Algorithm is used to solve the model. 2.EFFECTS OF PROJECTS PRIORITY ON HUMAN RESOUCE ALLOCATION AND THE
AFFECTING FACTORS OF PROJECT’S PRIORITY
Resource sharing is one of the main characteristics of multi-project management .The allocation of shared resources relates to the efficiency and rationality of the use of resources .When
resource conflict occurs ,the resource demand of the project with highest priority should be satisfied first. Only after that, can the projects with lower priority be considered.
Based on the idea of project classification management ,this paper classifies the affecting factors of project’s priority into three categories ,as the proj ect’s benefits ,the complexity of project management and technology , and the strategic influence on the enterprise’s future development . The priority weight of the project is the function of the above three categories, as shown in (1).
W=f(I,c,s…) (1)
Wh ere w refers to project’s priority weight; I refers to the benefits of the project; c refers to the complexity of the project, including the technology and management; s refers to the influence
of the project on enterprise .The bigger the values of the three categories, the higher the priority is.
3.HUMAN RESOURCE ALLOCATION MODEL IN MULTI-PROJECT ENVIRONMENT
3.1Problem Description
According to the constraint theory, the enterprise should strictly differentiate the bottleneck resources and the non-bottleneck resources to solve the constraint problem of bottleneck resources .This paper will stress on the limited critical human resources being allocated to multi-project with definite duration times and priority.
To simplify the problem, we suppose that that three exist several parallel projects and a shared resources storehouse, and the enterprise’s operation only involves one kind of c ritical human resources. The supply of the critical human resource is
limited, which cannot be obtained by hiring or any other ways during a certain period .when resource conflict among parallel projects occurs, we may allocate the human resource to multi-project according to project’s priorities .The allocation of non-critical independent human resources is not considered in this paper, which supposes that the independent resources that each project needs can be satisfied.
Engineering projects usually need massive critical skilled human
resources in some critical chain ,which cannot be substituted by the other kind of human resources .When the critical chains of projects at the same time during some period, there occur resource conflict and competition .The paper also supposes that the corresponding network planning of various projects have already been established ,and the peaks of each project’s resources demand have been optimized .The delay of the critical chain will affect the whole project’s duration t ime .
3.2 Model Hypotheses
The following hypotheses help us to establish a mathematical model:
(1)The number of mutually independent projects involved in
resource allocation problem in multi-project is N. Each
project is indicated with Q i ,while i=1,2, … N.
(2)The priority weights of multi-project have been
determined ,which are respectively w 1,w 2…w n .
(3)The total number of the critical human resources is R ,with
r k standing for each person ,while k=1,2, …,R
(4)Δk
i = others toprojectQ rcer humanresou i k 01
(5)Resources capturing by several projects begins on time. t
E
i is
the expected duration time of project I that needs the critical resources to finish some task after time t ,on the premise that the human resources demand can be satisfied .tAi is the real duration time of project I that needs the critical resource to finish some task after time t .
(6)According to the contract ,if the delay of the project happens
the daily cost loss due to the delay is △c i for project
I .According to the projec t’s importance ,the delay of a
project will not only cause the cost loss ,but will also damage the prestige and status of the enterprise .(while the latent cost is difficult to quantify ,it isn’t considered in this article temporarily.)
(7)From the hypothesis (5) ,we can know that after time t ,the
time-gap between the real and expected duration time of project I that needs the critical resources to finish some task is △t i,( △t i=t A i-t E i). For there exists resources competition, the time –gap is necessarily a positive number.
(8)According to hypotheses (6) and (7), the total cost loss of
project I is C i (C i= △t i* △C i ).
(9)The duration time of activities can be expressed by the
workload of activities divided by the quantity of resources ,which can be indicated with following expression of t A i =ηi/R i*,.In the expression , ηi refers to the workload of projects I during some period ,which is supposed to be fixed and pre-determined by the project managers on project planning
phase ; R i * refers to the number of the critical human resources
being allocated to projects I actually, with the equation R i * =∑=R k ki 1δ
existing. Due to the resource competition the
resource demands of projects with higher
Priorities may be guarantee, while those projects with lower priorities may not be fully guaranteed. In this situation, the decrease of the resource supply will lead to the increase of the duration time of activities and the project, while the
workload is fixed.
3.3 Optimization Model
Based on the above hypotheses, the resource allocation model
in multi-project environment can be established .Here, the optimization model is :
F i =min Z i = min ∑∑==N
i i N i Ci 11ω =min i i N i i N i c t ??∑∑==1
1ω (2) =min ∑∑==N i i N i 11ω )
E i R i ki i t - ??∑=1δη i c ? 2
F =min Z 2=min ()i t ?=min )
E i R i ki i t -
∑=1δη (3)。