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(21 - 40 of 228)
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- Title
- WEB-BASED CONTEMPORANEOUS DELAY ANALYSIS
- Creator
- Pektas, Murat
- Date
- 2011-11-22, 2011-12
- Description
-
The construction industry is fragmented due to the many stakeholders and the diverse phases involved in a construction project. On time,...
Show moreThe construction industry is fragmented due to the many stakeholders and the diverse phases involved in a construction project. On time, within budget, with required quality are essentials of a successful project. However, most construction projects are faced with delays, which obstruct success. To recover the damage caused by delays, both the delays and the parties responsible for them should be identified accurately. Daily window delay analysis outperforms other delay analysis methods, but it requires intensive day-by-day information. The information flow among the project stakeholders must be smooth and speedy at all stages of the production process not only to achieve the basic project objectives but also to let project stakeholders recognize the delays and the parties responsible for them in order to recover time and cost. The Internet is attractive for transferring information promptly and economically with no regional or temporal borders. To merge the power of the Internet and to ease time consuming delay analysis, a web-based application is proposed to analyze delays effectively and contemporaneously, to reduce time and cost, and to provide historical data. The application considers the day-by-day variation in critical path(s) during the project life cycle. The application gives accurate and repeatable results for apportioning project delays, accelerations and decelerations among involved parties. The manual effort required by traditional systems is minimized with the application’s simple, easy to use, yet effective and highly automated features. Moreover, the database structure of the application is designed to store and manage more than one project at a time to let its users calculate the overall performance of the company including all projects, and to calculate average durations for activities that can come up in future projects.
M.S. in Civil Engineering, December 2011
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- Title
- A METHODOLOGY FOR MAJOR BUS ROUTE RESCHEDULING TO IMPROVE TRANSIT PERFORMANCE
- Creator
- Lu, Xi
- Date
- 2012-08-01, 2012-07
- Description
-
In a period of growing transit operating deficits, increasing attention and concern is being directed at both the decreasing levels of...
Show moreIn a period of growing transit operating deficits, increasing attention and concern is being directed at both the decreasing levels of productivity of transit systems in general and the broad differences in measured service performance compiled for various transit systems. The purpose of this study is an assist public transit managers by providing them with a mathematical technique to analyze the efficiency with which serviced is produced and the effectiveness with which it is consumed. By providing the analysis model which not requires an extensive amount of data, the operator can have tool for decision-making of profit and market growth. Thus, transit managers will be able to access the performance of the agency and areas where improvements can be realistically achieved. Using the urban operation of the Chicago Transit Authority, a transit performance model is developed to analysis efficiency and effectiveness of the city's bus system. As the system exists, there are 144 bus routes start and end, frequency of dispatching buses and ridership changes from Weekdays and Weekend, peak hour and off-peak hour. In many of these routes, vehicles are used inefficiently and ineffectively, only a few passengers carried in some routes in off-peak hour, yet in other routes through the Central Business District (CBD) area, there are always not enough buses in peak hour. Also, some routes cannot provide enough on-time arrival service and some special group like elderly and handicapped cannot receive enough service in certain area. The goal of case research is to determine to understand the transit performance of Chicago Transit Authority and to select the optimal improvement projects to maximize the performance in term of economy and social equity.
M.S. in Civil Engineering, July 2012
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- Title
- DAMAGE DETECTION OF STRUCTURES USING INTERVAL FINITE ELEMENT METHOD
- Creator
- Venkitaraman, Shyamala
- Date
- 2012-04-16, 2012-05
- Description
-
Health assessment and damage detection for existing structures is an essential procedure for their safe and reliable operation so that any...
Show moreHealth assessment and damage detection for existing structures is an essential procedure for their safe and reliable operation so that any catastrophic failure may be prevented in a timely manner. However, results obtained from a health assessment of a structure possess uncertainties in measurements, system properties and loads. Furthermore, the conventional deterministic structural analyses are incapable of considering these uncertainties, thereby resulting in error when estimating the state of health of a structure. Interval (unknown-but-bounded) representation is one method to quantify uncertainty in a physical system. Using an interval variable, the uncertain parameter is bounded between extreme values. In this work, a new method for damage assessment of structures is developed that utilizes the results from structural health assessment as uncertain input parameters in an interval finite element analysis scheme. This method, due to its capability of considering uncertainties, offers a more robust process for estimating the possible existence of damage and overall health of the structure. As an illustrative example, the method is applied for a failed sign support structure. First, the structure's response from previous health assessment procedure was used to construct uncertain interval responses. Then using these interval responses as input parameters, an interval finite element method was performed. The results of the analysis verify and correlate with the failure location of the actual structure. Moreover, the lifetime assessment of the structure obtained from this method is the lower bound of, and correlates with the actual failure time of the structure.
M.S. in Civil Engineering, May 2012
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- Title
- DETERMINATION OF REDUNDANCY IN STRUCTURES USING INTERVAL UNCERTAINTY ANALYSIS
- Creator
- Amirshaghaghi, Sayeh
- Date
- 2014, 2014-05
- Description
-
Existence of redundancy in structures plays an important role in increasing their safety and reliability. However, using state-of-the-art...
Show moreExistence of redundancy in structures plays an important role in increasing their safety and reliability. However, using state-of-the-art deterministic and probabilistic approaches, all possibilities for estimation of redundancy (e.g. due to occurrence of different damage scenarios) have not been considered. One of the methods to quantify the presence of uncertainties in a system is to use interval variables. In this work, a new method for estimating the redundancy using interval structural analysis is developed. This method, hereafter referred to as Interval Redundancy Analysis (IRA), is robust and considers possibilities of strength reduction for each element leading to failure. Independent intervals for reduction of the strength for five damage scenarios of intact, slightly damage, moderately damaged, severely damaged, and completely damaged as well as strength of each element are considered. A numerical example to show the behavior of the developed method with comparison to Monte-Carlo simulation results is presented.
M.S. in Civil Engineering, May 2014
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- Title
- Emotional reactions to variations in contract language
- Creator
- Menches, Cindy L., Dorn, Lawrence
- Date
- 2012-07-20, 2012-07-25
- Description
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This article introduces a theory of emotion-driven behavior in construction contracting and provides support for this theory by presenting the...
Show moreThis article introduces a theory of emotion-driven behavior in construction contracting and provides support for this theory by presenting the quantitative results of a study on the emotional reaction of individuals to the language in contract clauses. Four different versions of the standard Delay Clause found in most construction contracts were extracted from four different contracts and were presented to a group of 27 individuals. Participants rank ordered the clause versions from 1 (most negative) to 4 (most positive). Overall, Clause Version 2 was ranked as having the most negative contract language, with nearly 75% of the participants ranking it as most negative. In contrast, Clause Version 4 was ranked as having the most positive contract language, with over 50% of the participants ranking it as most positive. Participants likewise selected negative emotion words to describe their reaction to Clause Version 2 and positive emotion words to describe their reaction to Clause Version 4. The findings suggest that contract clauses that contain negative language do tend to generate negative emotional reactions while positive contract language do tend to generate positive emotional reactions.
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- Title
- NSF Annual Report 2012 on Flexible Decision-making in Response to Disruptive Events on Construction Sites
- Creator
- Menches, Cindy L., Chen, Juan
- Date
- 2012-06-29, 2012-06-29
- Description
-
This 2012 annual research report submitted to the National Science Foundation describes: (1) involved people, (2) research activities, (3)...
Show moreThis 2012 annual research report submitted to the National Science Foundation describes: (1) involved people, (2) research activities, (3) research findings, (4) training and development, (5) outreach activities, (6) publications, and (7) contributions for rant number CMMI-1100514, Flexible Decision-making in Response to Disruptive Events on Construction Sites.
Sponsorship: National Science Foundation Award Number: CMMI-1100514
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- Title
- Using ecological momentary assessment to understand a construction worker’s daily disruptions and decisions (Working Paper)
- Creator
- Menches, Cindy L., Chen, Juan
- Date
- 2012-06-01, 2012-06-01
- Description
-
Capturing the momentary decisions and actions made by construction workers in response to workflow disruptions is challenging because, until...
Show moreCapturing the momentary decisions and actions made by construction workers in response to workflow disruptions is challenging because, until now, there has not been a minimally-disruptive data collection method that allows workers to identify their decision process “in the moment.” However, an Ecological Momentary Assessment (EMA) method – designed to capture momentary work experiences in natural settings – can provide researchers with detailed information about the daily challenges experienced by workers during the course of performing their tasks. An explanation of the method is provided, along with examples of the types of research questions that can be addressed and appropriate analysis techniques. The EMA method is being used on a federally-funded research program in the United States that is investigating how construction workers adapt to workflow disruptions by improvising their decisions and actions. Consequently, this article demonstrates the use of the method by presenting an idiographic study of William, an electrical construction worker. The evaluation of William’s disruptions, decisions, and actions elucidated an important relationship: every one of William’s disruptions required an improvisational action in order to continue working. The EMA method opens the door to the development of new theories about rapid decisions and subsequent actions on construction sites.
Sponsorship: National Science Foundation
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- Title
- ORGANIZATIONAL FLEXIBILITY IN CONSTRUCTION COMPANIES
- Creator
- Taghizadeh Khamesi, Hossein
- Date
- 2016, 2016-05
- Description
-
Flexibility is a key factor for an organization survival in a changing environment. Considering the cyclical nature of construction demand,...
Show moreFlexibility is a key factor for an organization survival in a changing environment. Considering the cyclical nature of construction demand, organizational flexibility is of special importance in construction company management. Most previous studies tried to categorize the response strategies of construction contractors to business and environmental changes. However, there is gap in the literature about the dynamic effect of organizational flexibility on the growth and competitiveness in construction companies. The objective of this study is to investigate the organizational flexibility of top construction contractors in the U.S. Engineering News-Records (ENR) top 400 contractors lists were used to collect data for the 52-year period 1963-2015. Using the collected data, several analyses were performed to find the relationship between organizational flexibility and competitive success. This attempt did not indicate a distinct relationship between organizational flexibility and competitiveness. It was found however that organizational flexibility is affected by change in the economy and that it was linked to company expansion/contraction. It is concluded that organizational flexibility is an essential advantage for construction contractors. Those contractors that are consistently ranked in the top 400 contractors list respond well to economic changes by expanding and contracting. On the other hand, different size contractors respond to changes in the economy differently, based on their resources and the nature of their work. In addition, this study concluded that those contractors that seek high growth rates face more fluctuations in their growth path and need more flexibility in response to them.
M.S. in Civil Engineering, May 2016
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- Title
- Water power development at Iowa Falls, Iowa
- Creator
- Dowdell, Charles O.
- Date
- 2009, 1907
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/waterpowerdevelo00dowd
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 12
- Title
- IMPROVEMENT OF BUS TRANSIT OPERATIONS BY MINIMIZING NON-REVENUE TRAVEL TIME
- Creator
- Arthur, Christina
- Date
- 2012-06-04, 2012-07
- Description
-
There are many activities in which a transit agency can investigate reduce costs. Three main activities include service cuts, renegotiations...
Show moreThere are many activities in which a transit agency can investigate reduce costs. Three main activities include service cuts, renegotiations of union labor contracts and modifications to bus operations. The first activity, cutting service, is often a last resort because not only must an agency adhere to its budget but also its service standards. Service cutting can involve route eliminations, stop eliminations, reroutes and reductions in spans of service and frequency of service. These service cuts greatly impact the riders in which routes serve as well as the image of the agency. In order to maintain customer satisfaction and ridership, an agency may decide to employ the latter two activities. In essence these two types of activities, singularly or in combination, can produce a reduction in overhead costs to the agency by more efficiently operating services. This paper focuses on modifications to bus operations as it relates to pull-in and pull-out trips, commonly referred to as deadheading and operator travel to relief points. Using the urban bus operation of the Chicago Transit Authority, a model is developed to assign routes to garages given the locations of the pull-in and pull-out locations associated with each route. As the system currently exists, there are seven garages distributed across the city from which 144 bus routes start and end. Many of these routes are operated out of multiple garages. The main reason for these route-to-multi-garage assignments is garage capacity and scheduling needs. The goal of this research is to determine how routes can be assigned to one specific garage and still meet the requirements given by the schedule.
M.S. in Civil Engineering, July 2012
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- Title
- TASK/STAFFING-TECHNOLOGY FIT IN CONSTRUCTION SCHEDULING
- Creator
- Yang, Juneseok
- Date
- 2015, 2015-07
- Description
-
Construction managers use scheduling methods such as the critical path method (CPM) and linear scheduling methods (LSM) to improve the outcome...
Show moreConstruction managers use scheduling methods such as the critical path method (CPM) and linear scheduling methods (LSM) to improve the outcome of their project. CPM is a popular scheduling method that is mostly based on precedence relationships and the identification of the longest path through a network. LSMs are based on a continuous flow of resources and are used mostly on projects that exhibit repetitive characteristics. Despite the many obvious advantages of CPM, its use in construction has been limited. LSMs are much less frequently used than CPM, although the general consensus is that LSMs are quite effective in projects composed of activities of repetitive nature. Understanding the reasons why these methods are not used as extensively as expected could improve their level of acceptance in the construction industry. The link between construction scheduling methods and the tasks expected to be performed by schedulers has been an on-going concern in the construction industry. The link between construction scheduling methods and the capabilities of the scheduling staff has also been an important issue. This study proposes a combined task/staffing-technology fit model to understand why CPM and LSM are not used as extensively as expected in construction scheduling: (1) a task-technology fit model that aims to measure the extent to which a construction scheduling method functionally matches the tasks expected to be performed by the scheduling staff; (2) a staffing-technology fit model that aims to measure the extent to which a construction scheduling method matches the staff`s experience, know-how and capabilities. The models that are proposed are an answer to the lack of proper instruments for evaluating the extent to which scheduling methods are used in the industry. A questionnaire survey was administered to professionals listed in the directory of the Construction Management Association of America (CMAA) who have many years of experience in construction scheduling. Statistical analyses were performed to determine statistical significance of the differences between the level of agreement concerning task-technology fit and staffing-technology fit for CPM and LSM applications. Findings indicate that there are significant differences between the opinions of CPM users and LSM users. This means that task-technology fit is much different in CPM and LSM applications. Similarly, staffing-technology fit is also quite different in CPM and LSM applications.
M.S. in Civil Engineering, July 2015
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- Title
- A system of street pavement for Naperville, Illinois
- Creator
- Beckman, H. E., Johnson, R. W., Peterson, I. C.
- Date
- 2009, 1909
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/systemofstreetpa00beck
Thesis (B.S.)--Armour Institute of Technology
- Title
- The structural design of a three-story reinforced concrete cold storage building
- Creator
- Wamsley, Gage R
- Date
- 2009, 1920
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/structuraldesign00wams
Thesis (B.S.)--Armour Institute of Technology;Includes folded leaves in back pocket
- Title
- Waterproofing of concrete by addition of commerical compounds
- Creator
- Hills, G. B, Cleaver, J. G, Schmidt, Fred
- Date
- 2009, 1911
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/waterproofingofc00hill
Thesis (B.S.)--Armour Institute of Technology, 1911 B.S. in Civil Engineering, 1911
- Title
- BUILDING SCIENCE MEASUREMENTS FOR THE HOSPITAL MICROBIOME PROJECT
- Creator
- Ramos, Tiffanie
- Date
- 2014, 2014-05
- Description
-
The Hospital Microbiome Project was designed to study the progression of microbial communities present inside and nearby patient rooms in a...
Show moreThe Hospital Microbiome Project was designed to study the progression of microbial communities present inside and nearby patient rooms in a new hospital pavilion recently built at the University of Chicago, both before the hospital was occupied and for nearly one year after introduction of patients and hospital staff. A suite of building science measurements, which is the focus of this work, was also designed and implemented to provide potentially meaningful data on several building environmental and operational parameters that may have influenced microbial communities inside the hospital. The building science measurement plan included characterizations of indoor air temperature, relative humidity (RH), absolute humidity, light levels, outdoor air fractions in the HVAC systems, room pressurization, and human occupancy using both beam break counters and CO2 concentrations in the 10 patient rooms and 2 nurse stations. Each parameter was measured at 5-minute intervals over the span of nearly one year, which resulted in more than 8 million collected data points. Air temperatures varied more than expected for such a typically tightly controlled environment, with surprisingly low correlations between rooms. RH and absolute humidity were highly correlated between patient rooms, indicating a strong effect from the HVAC system and little effect from occupants. Humidity was more tightly controlled during summer and winter months when the weather was most extreme in Chicago. Light intensity levels were not found to be very different between rooms and floors (which received similar solar exposure), but large seasonal patterns were apparent. CO2 was moderately correlated with non-directional IR beam-break counts at times, but not consistently. IR beam-break counters revealed large variations in patient room occupancy xv patterns throughout the study. In the HVAC systems serving each floor, outdoor air (OA) fractions were successfully calculated using CO2 concentrations measured in the outdoor air intake, recirculation air, and supply air, albeit only after periodic calibrations with data from the building automation system. OA fractions also showed distinct patterns of economizer usage with outdoor temperatures. Ultimately, this large suite of building science data will be used alongside microbial diversity data to explore correlations between indoor microbiology and the built environment.
M.S. in Environmental Engineering, May 2014
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- Title
- SENSITIVITY ANALYSIS: INFLUENCE OF INFLUENT VARIABLES ON A WRP MODEL
- Creator
- Wang, Xiaolong
- Date
- 2015, 2015-07
- Description
-
Balancing between cost and effluent quality at the Calumet water reclamation plants (WRP) is important. Influent quality has strong effects on...
Show moreBalancing between cost and effluent quality at the Calumet water reclamation plants (WRP) is important. Influent quality has strong effects on effluent quality. In this study, based on a simulation model, the influence of influent parameters on effluent ammonia concentration is identified by sensitivity analysis methods. Nine sensitivity analysis methods, including two mathematical methods, five statistical methods, and two graphical methods, are presented. Using different sensitivity analysis, most results presented all main effects have stronger effects than interactions among input variables on the output. Water temperature is always the most important parameter; the most important interaction effect is between water temperature and SS. Key words: Sensitivity analysis; water reclamation plants; design of experiments; simulation model; influent water quality; effluent ammonia
M.S. in Environmental Engineering, July 2015
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- Title
- AN OVERVIEW OF IMPROVED PROBABILISTIC METHODS FOR STRUCTURAL REDUNDANCY ASSESSMENT OF INDETERMINATE TRUSSES
- Creator
- Pathe, Julien Rene
- Date
- 2012-07-25, 2012-07
- Description
-
The redundancy of a structure refers to the extent of strength that is not considered in design. For an indeterminate structure a member...
Show moreThe redundancy of a structure refers to the extent of strength that is not considered in design. For an indeterminate structure a member failure does not necessarily induces the loss of integrity or functionality of the structure; rather it will affect its potential for safely carrying any future load. Numerous methods have been introduced in structural reliability literature to measure and implement the redundancy in design. However, in accordance with the semi-probabilistic approach of the codes which aim to develop design method providing consistent level of redundancy within the structure, the probability of failure of the structure has been proposed and is widely used as a redundancy measure. A classical method to compute the probability of failure of the structure based on failure paths is presented as a reference in this thesis. However, although extensively used, this method has major shortcomings which may lead to a misrepresentation of the structure redundancy. By using a geometric representation of members’ limit states associated with a loading regime, the research presented herein proposes an improved method for structural redundancy estimation that may be helpful to overcome problems associated with approximations and inconsistencies inherent in classics methods. Specific assumptions and/or procedures considered in the proposed method are described below. (1) An approximation is given to make the events of member failures mutually exclusive. (2) Geometric calculations are used to determine reliability indices and conditional reliability indices in order to establish closer bounds for the failure probability of individual structural members. (3) System’s failure probability is obtained using the assumption and procedures outlined in (1) and (2) above. (4) To further extend the method beyond geometrical redundancy, and to consider material redundancy, plasticity models commonly used in the structural analyses are considered in this study
M.S. in Civil Engineering, July 2012
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- Title
- Selecting a Compensation Strategy to Control Project Duration: Empirical Comparison of Lump Sum and Reimbursable Strategies (Working Paper)
- Creator
- Chen, Juan, Menches, Cindy L.
- Date
- 2012-05-01, 2012-05-01
- Description
-
Reducing project duration is a significant concern for many industries in the speed-to-market era. Numerous studies have examined the effects...
Show moreReducing project duration is a significant concern for many industries in the speed-to-market era. Numerous studies have examined the effects of project delivery methods on speeding up the process of construction. However, no study has quantitatively compared the effect of using different compensation strategies on schedule duration and schedule reduction. Using the data obtained from 175 international construction projects, this paper focuses on examining the influence of compensation strategy (lump sum versus reimbursable) on project duration while specifically taking into account the industry sector (heavy industrial versus light industrial). The results of the study provide empirical evidence that using a reimbursable compensation strategy can potentially shorten the procurement duration, construction duration, and overall project duration of heavy industrial projects. However, reimbursable contracting did not appear to reduce the project duration on light industrial projects.
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- Title
- Innovative Uses of Native CAD Files
- Creator
- Menches, Cindy L., Kleps, Stephen M.
- Date
- 2012-08-31, 2011-08-31
- Description
-
This technical report describes the outcomes resulting from conducting interviews with professional estimators within the electrical...
Show moreThis technical report describes the outcomes resulting from conducting interviews with professional estimators within the electrical construction industry. The purpose of the interviews was to identify whether native files are shared, why sharing does not occur more frequently, how file sharing might benefit the estimating process, and barriers to sharing native CAD files for the purpose of estimating from CAD drawings.
Sponsorship: Electri International
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- Title
- INVESTIGATION OF THE RELATIONSHIP BETWEEN BID PRICE AND CLAIMS IN PUBLIC BUILDING CONSTRUCTION PROJECTS
- Creator
- Vuong, Huy Anh
- Date
- 2014, 2014-07
- Description
-
This thesis focus on examining the relationship between bid price and claims in public construction projects in order to propose the...
Show moreThis thesis focus on examining the relationship between bid price and claims in public construction projects in order to propose the alternative bidding strategy and help owner minimize actual completion cost and gain the best value for their construction projects. The investigation on the literature of bidding methods, claims and their relationship guided us to come up with our hypotheses on building up an equation that quantitatively expressing the reverse correlation of bid price and claims. In order to archive our goal, data from 30 public construction projects were collected, and the statistic method and data analysis are utilized. Finally the equation to estimate the amount of claim from the bid price, the engineer’s estimate, and the spread between the lowest two bids are established through regression model. Even though some limitations are remained, the results from this study strongly recommend owners to prefer a contractor that offers the lowest bid and potential claim, rather than select the contractor using the traditional process of choosing the lowest bid.
M.S. in Civil Engineering, July 2014
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