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Analysis of tracing and capacity utilization by handlers in production / Analýza trasování a vytíženosti manipulantů v lisovací haleBark, Ondřej January 2015 (has links)
The diploma thesis focuses on tracing in layout by handlers between assembly lines in new plant for corporation Continental Automotive Czech Republic ltd, where boosters are produced. The theoretical part involves definitions of logistics, supply chain, material flow and handling equipment. Furthermore, methods of mathematic programming and software equipment are described, such as quadratic assignment problem, knapsack problem, travelling salesman problem from graph theory. In the practical part the situation in corporation has been analyzed and the data prepared for further examination. Then layout of plant and internal processes are evaluated and an appropriate model or concept of solution is selected. Subsequently, application in MS Excel is created with support of VBA scripts (3 kinds of layouts). The user manipulates with application followed by Solver for implementation of a new solution into practice. Finally, the models are interpreted and verified by Lingo. The focus of the thesis is the design of a layout change of a new plant including the description of tracing.
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Multi Colony Ant AlgorithmsMiddendorf, Martin, Reischle, Frank, Schmeck, Hartmut 25 October 2018 (has links)
In multi colony ant algorithms several colonies of ants cooperate in finding good solutions for an optimization problem. At certain time steps the colonies exchange information about good solutions. If the amount of exchanged information is not too large multi colony ant algorithms can be easily parallelized in a natural way by placing the colonies on different processors. In this paper we study the behaviour of multi colony ant algorithms with different kinds of information exchange between the colonies. Moreover we compare the behaviour of different numbers of colonies with a multi start single colony ant algorithm. As test problems we use the Traveling Salesperson problem and the Quadratic Assignment problem.
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NETWORKED ISSUE AGENDAS ON SOCIAL MEDIA: INTERRELATIONSHIPS BETWEEN POLARIZED CAMPAIGNS, NEWS MEDIA, AND PARTY SUPPORTERSArman, Zahedur Rahman 01 December 2022 (has links)
U.S. politics, media, and citizens are highly polarized, stipulating that society is divided between Democrats and Republicans (Hameleers, 2019). The U.S. has seen an increased political polarization over the past 25 years (Heltzel & Laurin, 2020; Westfall, Van Boven, Chambers, & Judd, 2015). Technological development in the campaign environment has fueled this political polarization (Hong & Kim, 2016). In such a polarized technological society, partisan news media cover political issues and events from their ideological perspective (Arceneaux, Johnson, & Murphy, 2012), which may affect the polarized citizens.The Republican Party is conservative, while the Democratic Party is liberal (Westfall, Van Boven, Chambers, & Judd, 2015). Each party has issue agendas that they prioritize during the campaign. When political campaigns post a message on social media, they not only post just one issue but several related issues. These interlinked issues have a networked effect on the partisan news media and the polarized citizens (McCombs, Shaw, & Weaver, 2014). How political campaigns interlinked different issue agendas during campaigns in a polarized environment has not been investigated. This study intends to see the similarities and dissimilarities between the Democratic and Republican Party issue networks using a network agenda setting theory during the 2020 U.S. presidential campaign and how they build and set networked issue agendas in the partisan news media and the polarized public on Facebook. The study uses a hybrid content analysis and network analysis of issue agendas presented by the Biden and Trump campaigns, partisan media (CNN and Fox News), and the Democratic Party and the Republican Party supporters on Facebook. Facebook posts are collected using Facebook’s CrowdTangle Search option from January 1, 2021, to November 3, 2020. This study uses a hybrid content analysis method which engages with both human coders and computational means to analyze big data sets (Guo et al., 2016). The data analysis involves measuring core-periphery block model, clique analysis, network visualization, and Quadratic Assignment Procedures (QAP). A social networking analysis software, UCINET, is used for measuring core-periphery block model, clique analysis, and QAP correlations(Borgatti, Everett, & Johnson, 2018). The scholarship of political campaign communication needs to reconnect to the ideological positions of political campaigns, partisan news media, and party supporters. This holistic study is significant in terms of better understanding the mechanism of networked agenda-setting activities of presidential campaigns in a polarized environment on Facebook. Methodologically, this study offers new techniques for investigating networked issue agendas of campaigns, news media, and citizens. It uses core-periphery block model and clique analysis as indicators of network agenda building and network agenda-setting influences. Social media practitioners like campaign managers can consider the political polarization, fragmented nature of social media, and polarized audience during political campaigning.
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Drawing DNA Sequence NetworksOlivieri, Julia 12 August 2016 (has links)
No description available.
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Smart Delivery Mobile Lockers: Design, Models and AnalyticsLiu, Si January 2024 (has links)
This doctoral thesis represents pioneering research in integrating Smart Mobile Lockers
with City Buses (SML-CBs) for e-commerce last-mile delivery, a novel concept rooted
in the sharing economy. It explores the innovative use of underutilized urban bus capacities
for parcel transportation while incorporating smart parcel lockers to facilitate
self-pick-up by customers. Comprising six chapters, the thesis delineates its background,
motivations, contributions, and organization in Chapter 1. Chapter 2 presents a comprehensive review of the recent literature on last-mile freight deliveries, including a bibliometric
analysis, identifying gaps and opportunities for SML-CBs intervention. In Chapter
3, using survey data, we conduct empirical analytics to study Canadian consumers’
attitudes towards adopting SML-CBs, focusing on deterrents such as excessive walking
distances to pick-up locations and incentives led by environmental concerns. This chapter
also pinpoints demographic segments likely to be early adopters of this innovative
delivery system. To address the concerns over walking distances identified in Chapter 3,
Chapter 4 presents a prescriptive model and algorithms aimed at minimizing customer
walking distance to self-pick-up points, considering the assignment of SML-CBs and customers.
The case study results endorse the convenience of SML-CBs in terms of short
walking distances. To systematically assess the sustainability benefits, a key motivator
identified in Chapter 3, Chapter 5 includes analytical models for pricing and accessibility
of SML-CBs. It also employs a hybrid life cycle assessment (LCA) methodology to
analyze the sustainability performance of SML-CBs. It establishes system boundaries,
develops pertinent LCA parameters, and illustrates substantial greenhouse gas (GHG)
savings in both operational and life cycle phases when SML-CBs are utilized instead of
traditional delivery trucks. The dissertation is concluded in Chapter 6, summarizing the
principal contributions and suggesting avenues for future research. This comprehensive
study not only provides empirical and analytical evidence supporting the feasibility and
advantages of SML-CBs but also contributes to the literature on sustainable logistics
and urban freight deliveries. / Thesis / Doctor of Philosophy (PhD) / This doctoral thesis represents pioneering research in integrating Smart Mobile Lockers
with City Buses (SML-CBs) for e-commerce last-mile delivery. It explores the innovative
use of underutilized urban bus capacities for parcel transportation while incorporating
smart parcel lockers to facilitate self-pick-up by customers. Comprising six chapters,
the thesis delineates its background, motivations, contributions, and organization in
Chapter 1. Chapter 2 presents a comprehensive review of the recent literature on lastmile
freight deliveries. In Chapter 3, we study Canadian consumers’ attitudes towards
adopting SML-CBs, focusing on deterrents such as excessive walking distances to pickup
locations and incentives led by environmental concerns. To address the concerns over
walking distances identified in Chapter 3, Chapter 4 presents models and algorithms for
operating SML-CBs. Chapter 5 presents an assessment of the sustainability of SML-CBs.
The dissertation is concluded in Chapter 6, summarizing the principal contributions and
suggesting avenues for future research.
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Optimal Air Defense Strategies For A Naval Task GroupKarasakal, Orhan 01 January 2004 (has links) (PDF)
We develop solution methods for the air defense problem of a naval task group in this dissertation. We consider two interdependent problems. The first problem is the optimal allocation of a set of defensive missile systems of a naval task group to a set of attacking air targets. We call this problem the Missile Allocation Problem (MAP). The second problem called the Sector Allocation Problem (SAP) is the determination of a robust air defense formation for a naval task group by locating ships in predefined sectors on the surface. For MAP, we present three different mixed integer programming formulations. MAP by its nature requires real time solution. We propose efficient heuristic solution procedures that satisfy the demanding time requirement of MAP. We also develop mathematical programming models for SAP. Proposed branch and bound solution scheme for SAP yields highly satisfactory solutions. We characterize the interaction between MAP and SAP and develop an integrated solution approach.
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The Allure of Departed Colleagues : An Examination of Career Mobility in Competitive Labor MarketsGopakumar, M G January 2015 (has links) (PDF)
In global corporations, work is increasingly organized around projects and individuals are constantly working with new constellations of partners across locational and temporal boundaries. In order to be successful in such settings, individuals have to form and maintain relationships with those they need to learn from and coordinate with. Recent studies suggest that these social ties provide resources and support as well as create normative pressures that strengthen the attachment of employees with the firm and lead them to stay with the firm. In contrast, the strength of an individual’s attachment with the organization given the departure of connected colleagues remains largely under theorized, and consequently, its implications have not been adequately studied. We address these gaps by examining whether ties to colleagues who leave the firm activate different mechanisms which can weaken their binds with the organization. This study assume significance in the context of contemporary free-agent labor markets where career trajectories are proposed to unfold in a series of short stints at multiple firms as opposed to life-long career in a single firm.
We develop theoretical arguments predicting the effect of workplace relationships on career mobility decisions by building on prior research into distributed work, changing nature of careers, social comparison, homophily, and structural equivalence. The main contention of this study is that the departure of one or more coworkers serves as powerful signals that unsettle the feeling of belongingness the focal employee enjoys with other teammates who choose to stay with the firm. Further, we propose that the influence of those departed employees will be higher when they are collocated and occupied similar professional roles as the focal employee.
To test the arguments, we analyze entire project co-assignment data across five years that linked 728 geographically distributed employees who were engaged in software development and delivery activities at a multi-national high technology firm. Our findings suggest that instead of seeking belonging and viability with coworkers, employees are actively seeking cues from their network of colleagues and continuously making subjective assessments of career success. In distributed work settings, such cues circulate more among physically proximate than distant employees and formal roles of coworkers serve as referent points for those signals. These mechanisms collectively influence voluntary turnover decisions. Using a classification model, we further demonstrate how insights from this study can be used by human resource management practitioners to assess and contain the flight risk of their valuable talent.
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THE EVACUATION PROBLEM IN MULTI-STORY BUILDINGSCung, Quang Hong 19 March 2019 (has links)
The pressure from high population density leads to the creation of high-rise structures within urban areas. Consequently, the design of facilities which confront the challenges of emergency evacuation from high-rise buildings become a complex concern. This paper proposes an embedded program which combines a deterministic (GMAFLAD) and stochastic model (M/G/C/C State Dependent Queueing model) into one program, GMAF_MGCC, to solve an evacuation problem. An evacuation problem belongs to Quadratic Assignment Problem (QAP) class which will be formulated as a Quadratic Set Packing model (QSP) including the random flow out of the building and the random pairwise traffic flow among activities. The procedure starts with solving the QSP model to find all potential optimal layouts for the problem. Then, the stochastic model calculates an evacuation time of each solution which is the primary decision variable to figure the best design for the building. Here we also discuss relevant topics to the new program including the computational accuracy and the correlation between a successful rate of solving and problems’ scale. This thesis examines the relationship of independent variables including arrival rate, population and a number of stories with the dependent variable, evacuation time. Finally, the study also analyzes the probability distribution of an evacuation time for a wide range of problem scale.
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Affectation de composantes basée sur des contraintes énergétiques dans une architecture multiprocesseurs en trois dimensionsDeldicque, Martin 06 1900 (has links)
La lithographie et la loi de Moore ont permis des avancées extraordinaires dans
la fabrication des circuits intégrés. De nos jours, plusieurs systèmes très complexes
peuvent être embarqués sur la même puce électronique.
Les contraintes de développement de ces systèmes sont tellement grandes qu’une
bonne planification dès le début de leur cycle de développement est incontournable.
Ainsi, la planification de la gestion énergétique au début du cycle de développement est
devenue une phase importante dans la conception de ces systèmes.
Pendant plusieurs années, l’idée était de réduire la consommation énergétique en
ajoutant un mécanisme physique une fois le circuit créé, comme par exemple un dissipateur de chaleur. La stratégie actuelle est d’intégrer les contraintes énergétiques dès les premières phases de la conception des circuits. Il est donc essentiel de bien connaître la dissipation d’énergie avant l’intégration des composantes dans une architecture d’un système multiprocesseurs de façon à ce que chaque composante puisse fonctionner efficacement dans les limites de ses contraintes thermiques. Lorsqu’une composante fonctionne, elle consomme de l’énergie électrique qui est transformée en dégagement de chaleur.
Le but de ce mémoire est de trouver une affectation efficace des composantes dans
une architecture de multiprocesseurs en trois dimensions en tenant compte des limites
des facteurs thermiques de ce système. / Lithography and Moore’s law have led to extraordinary advances in integrated
circuits manufacturing. Nowadays, many complex systems can be embedded on the
same chip.
Development constraints of these systems are so significant that a good planning
from the beginning of the development stage is essential. Thus, the planning of energy
management at the beginning of the development cycle has become important in the
design of these systems.
For several years, the idea was to reduce energy consumption by adding a cooling
system once the circuit is created, a heat sink for example. The current strategy is to integrate energy constraints in the early stages of circuits design. It is therefore important to know the energy dissipation before the integration of the components in the architecture of a multiprocessor system so that each component can work within the limits of its thermal stresses. When a component is running, it consumes electric energy which is converted into heat.
The aim of this thesis is to find an efficient assignment of components in a multiprocessor system architecture in three dimensions, taking into account the limits of its thermal factors.
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Otimização do processo de inserção automática de componentes eletrônicos empregando a técnica de times assíncronos. / Using A-Teams to optimize automatic insertion of electronic components.Rabak, Cesar Scarpini 22 June 1999 (has links)
Máquinas insersoras de componentes são utilizadas na indústria eletrônica moderna para a montagem automática de placas de circuito impresso. Com a competição acirrada, há necessidade de se buscar todas as oportunidades para diminuir custos e aumentar a produtividade na exploração desses equipamentos. Neste trabalho, foi proposto um procedimento de otimização do processo de inserção da máquina insersora AVK da Panasonic, implementado em um sistema baseado na técnica de times assíncronos (A-Teams). Foram realizados testes com exemplos de placas de circuito impresso empregadas por uma indústria do ramo e problemas sintéticos para avaliar o desempenho do sistema. / Component inserting machines are employed in the modern electronics industry for the automatic assembly of printed circuit boards. Due the fierce competition, there is a need to search for all opportunities to reduce costs and increase the productivity in the exploitation of these equipment. In this work we propose an optimization procedure for the insertion process of the AVK Panasonic inserting machine, implemented in a system based on asynchronous teams (A-Teams). Tests were conducted using as examples both printed circuit boards used by a particular industry of the realm and synthetic problems for the evaluation of the system.
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