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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Package Dependencies Analysis and Remediation in Object-Oriented Systems

Laval, Jannik 17 June 2011 (has links) (PDF)
Les logiciels évoluent au fil du temps avec la modification, l'ajout et la suppression de nouvelles classes, méthodes, fonctions, dépendances. Une conséquence est que le comportement peut être placé dans de mauvais paquetages et casser la modularité du logiciel. Une bonne organisation des classes dans des paquetages identifiables facilite la compréhension, la maintenance, les tests et l'évolution des logiciels. Nous soutenons que les responsables manquent d'outils pour assurer la remodularisation logicielle. La maintenance des logiciels nécessite des approches qui aident à (i) la compréhension de la structure au niveau du paquetage et l'évaluation de sa qualité; (ii) l'identification des problèmes de modularité, et (iii) la prise de décisions pour le changement. Dans cette thèse nous proposons ECOO, une approche qui aide la remodularisation. Elle concerne les trois domaines de recherche suivants: (i) Comprendre les problèmes de dépendance entre paquetages. Nous proposons des visualisations mettant en évidence les dépendances cycliques au niveau des paquetages; (ii) Proposer des dépendances qui devraient être changées. L'approche propose des dépendances à changer pour rendre le système plus modulaire; (iii) Analyser l'impact des changements. L'approche propose une analyse d'impact du changement pour essayer les modifications avant de les appliquer sur le système réel. L'approche présentée dans cette thèse a été validée qualitativement et les résultats ont été pris en compte dans la réingénierie des systèmes analysés. Les résultats obtenus démontrent l'utilité de notre approche.
232

Konsekvensanalys : en värdefull delprocess vid förändringsarbete i organisationer / Impact Analysis : a valuable sub process in creating organizational change

Angemo, Per January 2009 (has links)
ABSTRAKT  Syfte: Detta arbete har haft två syften: 1) Att skapa en ökad förståelse för hur en organisationsövergripande konsekvensanalys kan inverka på förändringsprocessers utfall. samt 2) Att inleda utvecklingen av ett pedagogiskt verktyg för att genomföra konsekvensanalys i förändringsprocesser samt genomföra ett inledande test av detta verktyg. Metod: Detta arbete är en kvalitativ fallstudie. Efter en inledande litteraturstudie har metoden för datainsamling varit kvalitativa intervjuer av såväl ostrukturerad som semi-strukturerad karaktär. Vid analysen av insamlad data har tillämpats ett hermeneutiskt synsätt. Resultat & slutsats: Den i undersökningen genomförda konsekvensanalysen visar tydligt hur en konsekvensanalys kan förändra underlaget för beslut, planering och implementering av förändring i organisationer. Grund för konsekvensanalysens betydelse har således funnits i såväl teori som empiri. Testet av verktyget visade att de fokusområden som tagits fram upplevdes som relevanta i undersökningsföretagets kontext. Verktyget kräver dock troligtvis vidareutveckling i form av en tydligare handledning och utbildning för att en förståelse av fokusområdenas innehåll och dess inverkan på varandra ska kunna skapas utan konsulthjälp i de flesta organisationer. Detta var ett inledande antagande som stärkts av undersökningens resultat. Förslag till fortsatt forskning: En svaghet i undersökningen är att konsekvensanalysen på grund av tillgången på undersökningsföretag fick utföras i ett annat skede av förändringsprocessen än vad som är tänkt vara dess huvudsakliga placering. Det vore önskvärt att i framtiden utföra det på sin tänkta placering, innan beslut om och planering av förändring. Med tanke på den aktuella organisationens begränsade verksamhet då den i princip enbart innefattar försäljning vore det också både intressant och nödvändigt att testa fokusområdenas relevans och konsekvensanalysens inverkan på en större organisation med en högre grad av diversifiering av verksamheten. Dessa är båda lämpliga uppslag för framtida undersökningar. Uppsatsens bidrag: Min förhoppning är att denna uppsats skapat en ökad förståelse för en konsekvensanalys betydelse för ett förändringsarbetes resultat. Arbetet med ett verktyg för att utföra en konsekvensanalys har inletts. I färdigutvecklad form är min förhoppning att detta verktyg ska vara till hjälp för organisationer som ska genomföra förändringsarbete. Nyckelord: organisationsförändring, konsekvensanalys, förändringsprocess, förändringsledning / ABSTRACT Aim: This thesis has two purposes: 1) To create a better understanding of how an impact analysis may affect the outcome of organizational change processes   and   2) To initiate the development of a tool for carrying out an impact analysis in an organizational change process and carry out an initial test of this tool. Method: This thesis is a qualitative case study. After an initial literature review, the method of data collection has been qualitative interviews of unstructured and semi-structured nature. In the analysis of collected data a hermeneutic approach has been applied. Result & Conclusion: The impact analysis carried out in this case study clearly shows how an impact analysis can affect the basis of decision making, planning and implementation of change in organizations. Thus theoretical as well as empirical ground has been found for its value in organizational change processes.   The test of the tool showed that the focus areas developed were perceived as relevant in the company context. The tool, however, most likely needs further development in the form of a user's guide to achieve an understanding of the focus areas, their content, and their impact on each other, good enough to be applied without using external consulting services. This was an initial assumption that was strengthened by the results of the study. Suggestions for future research: One limitation of this study may be that the test of the tool had to be carried out at a different stage in the change process from what was initially planned. It would be suitable to test the tool at its originally suggested stage of a change process and also in an organization of a more diversified character. The above mentioned are both suggestions for future studies. Contribution of the thesis: My hope is that this thesis has created a better understanding of how an impact analysis may affect the outcome of organizational change projects. The development of a tool for carrying out an impact analysis has been initiated and in its future complete version this tool may well be of much help for organizations involved in organizational change projects. Key words: organizational change, impact analysis, change process, leading change
233

The effect of compact development on travel behavior, energy consumption and GHG emissions in Phoenix metropolitan area

Zhang, Wenwen 10 April 2013 (has links)
Suburban growth in the U.S. urban regions has been defined by large subdivisions of single-family detached units. This growth is made possible by the mobility supported by automobiles and an extensive highway network. These dispersed and highly automobile-dependent developments have generated a large body of work examining the socioeconomic and environmental impacts of suburban growth on cities. The particular debate that this study addresses is whether suburban residents are more energy intensive in their travel behavior than central city residents. If indeed suburban residents have needs that are not satisfied by the amenities around them, they may be traveling farther to access such services. However, if suburbs are becoming like cities with a wide range of services and amenities, travel might be contained and no different from the travel behavior of residents in central areas. This paper will compare the effects of long term suburban growth on travel behavior, energy consumption, and GHG emissions through a case study of neighborhoods in central Phoenix and the city of Gilbert, both in the Phoenix metropolitan region. Motorized travel patterns in these study areas will be generated using 2001 and 2009 National Household Travel Survey (NHTS) data by developing a four-step transportation demand model in TransCAD. Energy consumption and GHG emissions, including both Carbon Dioxide (CO₂) and Nitrous Oxide (N₂O) for each study area will be estimated based on the corresponding trip distribution results. The final normalized outcomes will not only be compared spatially between Phoenix and Gilbert within the same year, but also temporally between years 2001 and 2009 to determine how the differential land use changes in those places influenced travel. The results from this study reveal that suburban growth does have an impact on people's travel behaviors. As suburbs grew and diversified, the difference in travel behavior between people living in suburban and urban areas became smaller. In the case of shopping trips the average length of trips for suburban residents in 2009 was slightly shorter than that for central city residents. This convergence was substantially due to the faster growth in trip lengths for central city compared to suburban residents in the 8-year period. However, suburban residents continue to be more energy intensive in their travel behavior, as the effect of reduction in trip length is likely to be offset by the more intensive growth in trip frequency. Additionally, overall energy consumption has grown significantly in both study areas over the period of study.
234

Identifying Testing Requirements for Modified Software

Apiwattanapong, Taweesup 09 July 2007 (has links)
Throughout its lifetime, software must be changed for many reasons, such as bug fixing, performance tuning, and code restructuring. Testing modified software is the main activity performed to gain confidence that changes behave as they are intended and do not have adverse effects on the rest of the software. A fundamental problem of testing evolving software is determining whether test suites adequately exercise changes and, if not, providing suitable guidance for generating new test inputs that target the modified behavior. Existing techniques evaluate the adequacy of test suites based only on control- and data-flow testing criteria. They do not consider the effects of changes on program states and, thus, are not sufficiently strict to guarantee that the modified behavior is exercised. Also, because of the lack of this guarantee, these techniques can provide only limited guidance for generating new test inputs. This research has developed techniques that will assist testers in testing evolving software and provide confidence in the quality of modified versions. In particular, this research has developed a technique to identify testing requirements that ensure that the test cases satisfying them will result in different program states at preselected parts of the software. This research has also developed supporting techniques for identifying testing requirements. Such techniques include (1) a differencing technique, which computes differences and correspondences between two software versions and (2) two dynamic-impact-analysis techniques, which identify parts of software that are likely affected by changes with respect to a set of executions.
235

A Business Rule Approach To Requirements Traceability

Narmanli, Murat 01 September 2010 (has links) (PDF)
In this thesis, a requirements traceability model is proposed in order to make efficient and effective change request impact analysis. The proposed model is a requirements &ndash / requirements traceability model. There are several researches regarding software requirements traceability problem. The main problem of these researches is that the proposed solutions can not be applied to software industry with affordable changes. However, current literature begins to see that describing all the software requirements in a huge black box is not so much applicable to today&rsquo / s more dynamic and bigger software projects, especially regarding change management. The proposed traceability model tries to be a solution to these problems. Change requests and business rules are two important and popular terms for today&rsquo / s software industry. The traceability model consists of three types of software requirements: data definitions, business rules and use cases. The traceability model proposes bidirectional traces between these types. Data definitions, business rules and use cases are related to each other and they all should be seen as parts of a software system which should work together to make the software system work properly. Empirical investigation is made on a real industrial software project. These types were configured in order to match to the project specific needs in a reconfigurable way. Experimental results show that the traceability model has an acceptable degree of correctness.
236

Schedule Delay Analysis In Construction Projects: A Case Study Using Time Impact Analysis Method

Dayi, Songul 01 December 2010 (has links) (PDF)
Inadequate or weak preparatory work before starting construction of any structure may cause serious problems during the construction period. For example, projects without sufficient detailed drawings or construction schedules and a disorganized building site can create many problems in the management and completion of the construction works. Consequently, the cost of construction increases digressively, the construction duration of the project extends and the quality of construction is affected adversely. This study dwells on the importance of construction schedules in achieving the aim of producing good quality construction work within the specified duration. Monitoring continuously the interactive relation concerning delays in construction schedules and contractor demands is a complicated process. Here the simplest and basic approach is that, both for owner and contractor, time is money and for this reason construction schedule delays should be analyzed and corrective measures should be taken in a timely manner. The main purpose of this study is to investigate the causes of construction schedule delays and the methods of schedule delay analyses. In this context completion construction works of a covered swimming pool building in Ankara was selected as a case study for analyzing project scheduling and the delays therein. The &ldquo / Time Impact Analysis Method&rdquo / (TIA) was applied to the case study project using PRIMAVERA&reg / software in order to determine the construction schedule delays / to measure the impacts of these delays on the project completion duration / and to allocate responsibility amongst the project participants for preventing delay claims. After the application of the delay analysis it was observed that the delays in the critical activities extended the project duration by 57 days in total i.e. by 15.4 % of the estimated construction period. Fines should have been paid by the contractor because of 31-days non-excusable delays. Also, the contractor should have been given a time extension of 26-days due to 22-days excusable compensable delays and 4-days excusable non-compensable delays which were beyond the control of the contractor. These delays were caused due to organizational deficiencies of the owner, the bureaucracy of the provincial municipality, the lack of detail drawings during the municipality application, the lack of experience of the contractor, problems in material procurement, unforeseeable weather conditions and shortages of qualified employees of the subcontractors. It was observed that of these all except one correspond to the important causes of delays as reported in literature concerning public projects in Turkey.
237

Assessing operational impact in enterprise systems with dependency discovery and usage mining

Moss, Mark Bomi 15 July 2009 (has links)
A framework for monitoring the dependencies between users, applications, and other system components, combined with the actual access times and frequencies, was proposed. Operating system commands were used to extract event information from the end-user workstations about the dependencies between system, application and infrastructure components. Access times of system components were recorded, and data mining tools were leveraged to detect usage patterns. This information was integrated and used to predict whether or not the failure of a component would cause an operational impact during certain time periods. The framework was designed to minimize installation and management overhead, to consume minimal system resources (e.g. network bandwidth), and to be deployable on a variety of enterprise systems, including those with low-bandwidth and partial-connectivity characteristics. The framework was implemented in a test environment to demonstrate the feasibility of this approach. The system was tested on small-scale (6 computers in the GT CERCS Laboratory over 35 days) and large-scale (76 CPR nodes across the entire GT campus over 4 months) data sets. The average size of the impact topology was shown to be approximately 4% of the complete topology, and this size reduction was related to providing system administrators the capability to better identify those users and resources most likely to be affected by a designated set of component failures during a designated time period.
238

Evaluating developments of regional impact using TRANSIMS

Shealey, Stephanie Lynne 08 April 2010 (has links)
The thesis develops and documents a workflow for applying TRANSIMS to the analysis of Developments of Regional Impact (DRI). The proposed workflow will consider perspectives of both the transportation agency responsible for the evaluating the DRI and the transportation engineer responsible for performing the analysis. TRANSIMS offers a comprehensive framework for managing inputs and outputs that follow a transportation planning workflow. Not a single, monolithic software application, TRANSIMS is a suite of 65 small, light-weight, single-task tools for creating and manipulating GIS shape files and SQL data base files, estimating the elements of a four-step transportation modeling process, and computing link and vehicle delays for a given transportation network. Current analysis techniques for developments of regional impact require that the analyst apply arbitrary or non-repeatible estimates for trip assignments at the regional level. Because of the modular nature of the TRANSIMS, implementing each DRI as a layer in the GIS data base will permit the mixing and matching of multiple DRI within a local area, permitting a risk-based approach to the evaluation of multiple DRI, any of which may or may not actually happen. This thesis focuses exclusively on the review of DRI analysis techniques, review of TRANSIMS modules, and development of a proposed DRI workflow within the TRANSIMS framework.
239

Essays on sustainable operations

Agrawal, Vishal 15 June 2010 (has links)
With the increased attention of different stakeholders on the environmental performance of businesses, several firms are increasingly focusing on product recovery and reuse activities which are not only profitable but may also help to reduce the environmental impact of their operations. This dissertation focuses on managerial challenges associated with such value-added recovery and reuse activities. The first essay examines how a firm should bring a product to market, in particular, whether to lease or sell products. Motivated by claims that leasing can be an environmentally superior to selling, we analytically investigate if either leasing or selling can be both more profitable for a monopolist and have a lower total environmental impact. The second essay first experimentally examines the effect of remanufactured products on the perceived value of new products. This effect is then incorporated to analytically investigate an OEM's strategy in the presence of competition from third-party remanufacturers. In the third essay, motivated by a major IT company, we investigate the optimal product recovery and remanufacturing strategy for a firm that can offer trade-in rebates to achieve price discrimination. We also consider the effect of potential entry of third-party remanufacturers on the firm's recovery and remanufacturing strategy.
240

A methodology to enable rapid evaluation of aviation environmental metrics and aircraft technologies

Becker, Keith Frederick 16 May 2011 (has links)
Commercial aviation has become an integral part of modern society and enables unprecedented global connectivity by increasing rapid business, cultural, and personal connectivity. In the decades following World War II, passenger travel through commercial aviation quickly grew at a rate of roughly 8% per year globally. The FAA's most recent Terminal Area Forecast predicts growth to continue at a rate of 2.5% domestically, and the market outlooks produced by Airbus and Boeing generally predict growth to continue at a rate of 5% per year globally over the next several decades, which translates into a need for up to 30,000 new aircraft produced by 2025. With such large numbers of new aircraft potentially entering service, any negative consequences of commercial aviation must undergo examination and mitigation by governing bodies so that growth may still be achieved. Options to simultaneously grow while reducing environmental impact include evolution of the commercial fleet through changes in operations, aircraft mix, and technology adoption. Methods to rapidly evaluate fleet environmental metrics are needed to enable decision makers to quickly compare the impact of different scenarios and weigh the impact of multiple policy options. As the fleet evolves, interdependencies may emerge in the form of tradeoffs between improvements in different environmental metrics as new technologies are brought into service. In order to include the impacts of these interdependencies on fleet evolution, physics-based modeling is required at the appropriate level of fidelity. Evaluation of environmental metrics in a physics-based manner can be done at the individual aircraft level, but will then not capture aggregate fleet metrics. Contrastingly, evaluation of environmental metrics at the fleet level is already being done for aircraft in the commercial fleet, but current tools and approaches require enhancement because they currently capture technology implementation through post-processing, which does not capture physical interdependencies that may arise at the aircraft-level. The goal of the work that has been conducted here was the development of a methodology to develop surrogate fleet approaches that leverage the capability of physics-based aircraft models and the development of connectivity to fleet-level analysis tools to enable rapid evaluation of fuel burn and emissions metrics. Instead of requiring development of an individual physics-based model for each vehicle in the fleet, the surrogate fleet approaches seek to reduce the number of such models needed while still accurately capturing performance of the fleet. By reducing the number of models, both development time and execution time to generate fleet-level results may also be reduced. The initial steps leading to surrogate fleet formulation were a characterization of the commercial fleet into groups based on capability followed by the selection of a reference vehicle model and a reference set of operations for each group. Next, three potential surrogate fleet approaches were formulated. These approaches include the parametric correction factor approach, in which the results of a reference vehicle model are corrected to match the aggregate results of each group; the average replacement approach, in which a new vehicle model is developed to generate aggregate results of each group, and the best-in-class replacement approach, in which results for a reference vehicle are simply substituted for the entire group. Once candidate surrogate fleet approaches were developed, they were each applied to and evaluated over the set of reference operations. Then each approach was evaluated for their ability to model variations in operations. Finally, the ability of each surrogate fleet approach to capture implementation of different technology suites along with corresponding interdependencies between fuel burn and emissions was evaluated using the concept of a virtual fleet to simulate the technology response of multiple aircraft families. The results of experimentation led to a down selection to the best approach to use to rapidly characterize the performance of the commercial fleet for accurately in the context of acceptability of current fleet evaluation methods. The parametric correction factor and average replacement approaches were shown to be successful in capturing reference fleet results as well as fleet performance with variations in operations. The best-in-class replacement approach was shown to be unacceptable as a model for the larger fleet in each of the scenarios tested. Finally, the average replacement approach was the only one that was successful in capturing the impact of technologies on a larger fleet. These results are meaningful because they show that it is possible to calculate the fuel burn and emissions of a larger fleet with a reduced number of physics-based models within acceptable bounds of accuracy. At the same time, the physics-based modeling also provides the ability to evaluate the impact of technologies on fleet-level fuel burn and emissions metrics. The value of such a capability is that multiple future fleet scenarios involving changes in both aircraft operations and technology levels may now be rapidly evaluated to inform and equip policy makers of the implications of impacts of changes on fleet-level metrics.

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