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Bailey, O C (2008) Least-cost energy system design for commercial buildings: The relationship between end-use energy efficiency, distributed generation, and utility energy supply, Unpublished PhD Thesis, , Cornell University.

Bennett, F L (1966) Some approaches to the critical path scheduling resource allocation problem, Unpublished PhD Thesis, , Cornell University.

• Type: Thesis
• Keywords: complexity; duration; city planning; critical path method; programming; resource allocation; resource scheduling; scheduling; heuristic
• ISBN/ISSN:
• URL: https://www.proquest.com/docview/302188513
• Abstract:
  (INTRODUCTION) Since its introduction in 1957, the critical path method for scheduling project activities has achieved rapid acceptance in several fields. Projects in such diverse fields as construction, city planning and research and development, where operations are generally performed only once rather than in a cyclical, "assembly line" fashion, have benefited greatly from critical path types of analysis. In relating the activities of a project through the use of an arrow diagram, the planner is required to consider the sequence of operations for the entire project before it is begun. Further, the time estimates which are made for each activity in the project allow an estimate of the total duration of the work and a determination of those activities which are likely to influence this completion time to the greatest extent. As the work progresses, the time required for completing activities may be compared with the original estimates, and an updated project completion time may be predicted. The time which an individual activity requires for completion is usually closely related to the rate at which the various types of necessary resources are employed on the activity. To estimate an activity's duration without considering the assignment of resources to it is to Ignore one of the most important phases of any scheduling problem. And yet, a common feature of nearly all critical path scheduling to date is that it has not considered this question of resource allocation. Clearly, the assignment of resources to individual project activities is related in some degree to the amounts of the resources that are available for the project as a whole. Apparently early critical path analyses were made either ignoring this fact completely or assuming that resources were available in unlimited amounts. In many cases such an assumption is not valid. Two aspects of prime importance, then, in connection with resource allocation in critical path scheduling must be considered, 1) At the individual activity level, the duration and resource assignment are closely related and cannot be considered separately. 2) In terms of the overall project, the assignment of resources to activities for each unit of time must take into consideration the resources that are available to be assigned during that time. For most projects, it Is desirable to complete the work in as short a time as possible. When resources are limited, a project may require longer to complete than when they are not. The fundamental problem, therefore, may be stated as follows: Schedule the activities of a project network, some or all of which require resources which are available in limited amounts, in such a way that the duration of the project is a minimum and the limited resource levels are not exceeded. It is the purpose of this thesis to suggest and investigate several methods for dealing with this problem, in an attempt to provide a workable means by which the planner might meet these conditions. First, the basic features of "traditional" critical path scheduling methods will be presented. It should become clear, in tracing these early developments, that scheduling by this method has generally ignored the question of resource allocation. Recently, the problem of resource scheduling has begun to receive attention. Chapter 3 will review all of the published accounts of such work which the author could find. This review will reveal two important characteristics of these contributions. First, in nearly all of the approaches which have been suggested, there is no guarantee that the schedule which is obtained will allow completion of the project in the shortest possible time. Second, most of the methods which various authors have presented do not allow for more than one possible duration for each activity, whereas it might be more realistic to allow some activities to have various durations depending on the amounts of resources that were assigned to them. Chapter 4 will be devoted to the development of some mathematical models which can guarantee a minimum project duration while meeting the availability requirements. In general, the models will state that the project completion time is to be minimized, subject to the constraints that each activity must be completed, in terms of duration and resource needs; that the activities must be done in proper sequence; and that the resources assigned during each unit of time (usually one day) must not exceed the resources that are available. Four such models will be suggested. The first will deal with the case in which it is assumed that both the duration and resource assignment for each activity are fixed, so that, for example, a certain activity would be worked on for a given number of days, and on each of these days a given number of men would be assigned to the activity. In the other three models, it will be assumed that the duration of an activity can vary depending on the amount of its required resources which are assigned to it. In this case, a total resource requirement for an activity may be stated in, say, man-days, with no specification as to the activity's duration or daily resource assignment. Apparently these three models are the first published attempts to guarantee a minimum project duration for this "varying duration" case. These minimizing formulations require for their solution some rather recent developments in mathematical programming. Chapter 5 will report that author's experience in attempting to solve specific cases by the use of integer programming and quadratic programming. Although this experience was valuable in terms of testing some rather new mathematical techniques, the results indicate clearly that some difficulties would be involved in applying the models to actual planning situations. Because of the complexity and unpredictability of the models for assuring minimum project duration, a computer program was developed which can assign resources to the activities of a project in a logical manner, will allow activity durations to vary, and will assure that resource assignments do not exceed availabilities for each time unit of the project. However, there is no assurance that the resulting project duration will be an absolute minimum for the conditions of the project. This also appears to be the first published account of an heuristic technique which deals with the "varying duration" case. Experience with the program indicates that it could be used to schedule several resources simultaneously for projects having a reasonably large number of activities without requiring an excessively high computer run time. Finally, in Chapter 7, some of the advantages and limitations of the work will be pointed out and suggestions for further research will be made.

Huang, B (2017) A hierarchical multi-stakeholder principal-agent model for (anti-) corruption in public infrastructure procurement, Unpublished PhD Thesis, , Cornell University.

Perez Cordoba, X A (2013) Life-cycle cost optimization for foundation engineering, Unpublished PhD Thesis, , Cornell University.

Radu, A C (2015) Life-cycle estimates of structures subjected to seismic loads, Unpublished PhD Thesis, , Cornell University.

Tallant, D J (1993) Privatization in a developing economy: Lessons from the Turkish cement industry, Unpublished PhD Thesis, , Cornell University.

Vaidya, R (1981) The role of the construction industry in economic development: The case of Nepal, Unpublished PhD Thesis, , Cornell University.

Vaziri, K (2006) Program planning under uncertainty, Unpublished PhD Thesis, , Cornell University.