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1
Fong, Nga Hin Benjamin. "Modeling, Analysis,and Design of Responsive Manufacturing Systems Using Classical Control Theory." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/27269.
Повний текст джерелаАнотація:
The manufacturing systems operating within todayâ s global enterprises are invariably dynamic and complicated. Lean manufacturing works well where demand is relatively stable and predictable where product diversity is low. However, we need a much higher agility where customer demand is volatile with high product variety. Frequent changes of product designs need quicker response times in ramp-up to volume. To stay competitive in this 21st century global industrialization, companies must posses a new operation design strategy for responsive manufacturing systems that react to unpredictable market changes as well as to launch new products in a cost-effective and efficient way.
The objective of this research is to develop an alternative method to model, analyze, and design responsive manufacturing systems using classical control theory. This new approach permits industrial engineers to study and better predict the transient behavior of responsive manufacturing systems in terms of production lead time, WIP overshoot, system responsiveness, and lean finished inventory. We provide a one-to-one correspondence to translate manufacturing terminologies from the System Dynamics (SD) models into the block diagram representation and transfer functions. We can analytically determine the transient characteristics of responsive manufacturing systems. This analytical formulation is not offered in discrete event simulation or system dynamics approach. We further introduce the Root Locus design technique that investigates the sensitivity of the closed-loop poles location as they relate to the manufacturing world on a complex s-plane. This subsequent complex plane analysis offers new management strategies to better predict and control the dynamic responses of responsive manufacturing systems in terms of inventory build-up (i.e., leanness) and lead time. We define classical control theory terms and interpret their meanings according to the closed-loop poles locations to assist production management in utilizing the Root Locus design tool. Again, by applying this completely graphic view approach, we give a new design approach that determine the responsive manufacturing parametric set of values without iterative trial-and-error simulation replications as found in discrete event simulation or system dynamics approach.Ph. D.
2
Markovsky, Ivan. "Exact and approximate modeling of linear systems : a behavioral approach /." Philadelphia, Pa. : Society for Industrial and Applied Mathematics, 2006. http://www.loc.gov/catdir/enhancements/fy0708/2005057537-d.html.
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3
Cho, Tae Ho. "A hierarchical, modular simulation environment for flexible manufacturing system modeling." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186144.
Повний текст джерелаАнотація:
Computer simulation is one of the most widely used techniques in manufacturing systems study. The value of simulation increases constantly due to improvements in computing power. However models of large-scale systems tend to be very complex, and writing simulation programs to execute them can be an arduous task. Rapid modeling of such systems can play a significant role in the selecting manufacturing strategy. This dissertation deals with the design and implementation of tools that aid in such modeling activity by identifying some of the problems that occur frequently in the modeling of flexible manufacturing systems (FMS). This set of tools, collectively called the hierarchical modular modeling environment (HMME), is designed and implement by extending DEVS(Discrete EVent System Specification)-Scheme. The problems identified are in the field of model interconnections, embedding expert systems in models, model structuring and simulation display. An example, of operation overlapping strategy in a hierarchical FMS, demonstrates the utility of the environment. Although developed for FMS simulation, this modeling aid is applicable to many other domains of knowledge-based systems and intelligent control.
4
Oulton, David. "Selected papers on colorimetric theory and colour modeling." Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/selected-papers-on-colorimetric-theory-and-colour-modeling(e4f13600-5d8e-45a8-afce-846647130dfb).html.
Повний текст джерелаАнотація:
The annotated papers that are submitted as part of this thesis consider the phenomenon of colour at the fundamental, technical, and application levels, and they were written and published by Oulton between 1990 and 2009. The papers disclose significant insights by the author into colorimetric modeling theory and report aspects of the author's work that have led to commercially successful practical applications. The academic significance of these papers is evident in their citation record; their practical value is shown by a number of successful industrial collaboration programmes, and through the award of national prizes for innovation by the Worshipful Company of Dyers, and the Society of Dyers and Colorists. The published research primarily concerns digital devices that either capture or reproduce coloured images. For example, the research problem of how to calibrate the colour on computer CRT screens, which was thought at the time to be intractable, was reported by Oulton in paper 1 to be solved at the two to three significant figure level of colorimetric accuracy. This world leading level of accuracy was subsequently confirmed using a comprehensive data set in paper 7, and has been exploited internationally in commercial computer aided design and colour communication systems by Textile Computer Systems Ltd and Datacolor Inc. Further research problems resolved by Oulton in the presented papers include how to predict the colorimetric sensitivity of dye recipes; how to design, test, and fine-tune the spectral response of digital cameras; and how the individual customers in a shop can be tracked automatically to reveal their buying behavior, using coloured CCTV images.The challenge to the standard CIE colorimetric model posed by the results of Dr W.A. Thornton was analyzed and satisfactorily explained by Oulton in papers 2, 3 and 4. It is also shown that Thornton's results do not in any way compromise either the practice of colorimetry based on the CIE Standard Observer, or the validity of its quantifying data sets. It is also additionally shown under the annotation of paper 4 presented here, that the success of the CIE colorimetric model has a clearly demonstrable theoretical basis.In all but one of the presented papers the convention is maintained that the standard CIE XYZ co-ordinate model should be used as the reference basis, when modeling the properties of colour and quantifying its uses. The final paper to be published (and presented here as paper 4) challenges this convention and demonstrates that a context free and formally defined alternative reference basis may be used in colorimetric modeling with significant advantage. It is also shown in paper 4 that under the specified axioms, any cross dependency that is potentially non linear can in principle be resolved into its component scalar and additive relationships, and that the causes of scalar non linearity may be characterized independently from the causes of linearly additive cross dependency. The result is a widely applicable analytical and experimental design method for resolving complex cross dependent relationships in general and in particular, for resolving those between the spectral visual stimuli and the psychophysical response to them.
5
Balestrini, Robinson Santiago. "A modeling process to understand complex system architectures." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29621.
Повний текст джерелаАнотація:
Thesis (Ph.D)--Aerospace Engineering, Georgia Institute of Technology, 2010.Committee Chair: Mavris, Dimitri; Committee Member: Bishop, Carlee; Committee Member: German, Brian; Committee Member: Nixon, Janel; Committee Member: Schrage, Daniel. Part of the SMARTech Electronic Thesis and Dissertation Collection.
6
Cho, Jeongho. "Multiple modeling and control of nonlinear systems with self-organizing maps." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0008180.
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7
Xiong, Xiaolu. "Theory and Practice: Improving Retention Performance through Student Modeling and System Building." Digital WPI, 2017. https://digitalcommons.wpi.edu/etd-dissertations/139.
Повний текст джерелаАнотація:
The goal of Intelligent Tutoring systems (ITSs) is to engage the students in sustained reasoning activity and to interact with students based on a deep understanding of student behavior. In order to understand student behavior, ITSs rely on student modeling methods to observes student actions in the tutor and creates a quantitative representation of student knowledge, interests, affective states. Good student models are going to effectively help ITSs customize instructions, engage student's interest and then promote learning. Thus, the work of building ITSs and advancing student modeling should be considered as two interconnected components of one system rather than two separate topics. In this work, we utilized the theoretical support of a well-known learning science theory, the spacing effect, to guide the development of an ITS, called Automatic Reassessment and Relearning System (ARRS). ARRS not only validated the effectiveness of spacing effect, but it also served as a testing field which allowed us to find out new approaches to improve student learning by conducting large-scale randomized controlled trials (RCTs). The rich data set we gathered from ARRS has advanced our understanding of robust learning and helped us build student models with advanced data mining methods. At the end, we designed a set of API that supports the development of ARRS in next generation ASSISTments platform and adopted deep learning algorithms to further improve retention performance prediction. We believe our work is a successful example of combining theory and practice to advance science and address real- world problems.
8
Gopal, Kartik. "Modeling and Optimization of Hospital Transportation System." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1481314351566885.
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Qi, Chenkun. "Modeling of nonlinear distributed parameter system for industrial thermal processes /." access full-text access abstract and table of contents, 2009. http://libweb.cityu.edu.hk/cgi-bin/ezdb/thesis.pl?phd-meem-b23750911f.pdf.
Повний текст джерелаАнотація:
Thesis (Ph.D.)--City University of Hong Kong, 2009."Submitted to Department of Manufacturing Engineering and Engineering Management in partial fulfillment of the requirements for the degree of Doctor of Philosophy." Includes bibliographical references (leaves 167-187)
10
Moon, Kyungjin. "Self-reconfigurable ship fluid-network modeling for simulation-based design." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34733.
Повний текст джерелаАнотація:
Our world is filled with large-scale engineering systems, which provide various services and conveniences in our daily life. A distinctive trend in the development of today's large-scale engineering systems is the extensive and aggressive adoption of automation and autonomy that enable the significant improvement of systems' robustness, efficiency, and performance, with considerably reduced manning and maintenance costs, and the U.S. Navy's DD(X), the next-generation destroyer program, is considered as an extreme example of such a trend.
This thesis pursues a modeling solution for performing simulation-based analysis in the conceptual or preliminary design stage of an intelligent, self-reconfigurable ship fluid system, which is one of the concepts of DD(X) engineering plant development. Through the investigations on the Navy's approach for designing a more survivable ship system, it is found that the current naval simulation-based analysis environment is limited by the capability gaps in damage modeling, dynamic model reconfiguration, and simulation speed of the domain specific models, especially fluid network models.
As enablers of filling these gaps, two essential elements were identified in the formulation of the modeling method. The first one is the graph-based topological modeling method, which will be employed for rapid model reconstruction and damage modeling, and the second one is the recurrent neural network-based, component-level surrogate modeling method, which will be used to improve the affordability and efficiency of the modeling and simulation (M&S) computations. The integration of the two methods can deliver computationally efficient, flexible, and automation-friendly M&S which will create an environment for more rigorous damage analysis and exploration of design alternatives.
As a demonstration for evaluating the developed method, a simulation model of a notional ship fluid system was created, and a damage analysis was performed. Next, the models representing different design configurations of the fluid system were created, and damage analyses were performed with them in order to find an optimal design configuration for system survivability. Finally, the benefits and drawbacks of the developed method were discussed based on the result of the demonstration.
11
Zhang, Hanzhong. "A moving boundary problem in a distributed parameter system with application to diode modeling." Access restricted to users with UT Austin EID, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3037035.
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12
Bider, Ilia. "State-Oriented Business Process Modeling : Principles, Theory and Practice." Doctoral thesis, KTH, Computer and Systems Sciences, DSV, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3375.
Повний текст джерелаАнотація:
In the last 50 years, a considerable amount of research workhas been completed in the mathematical system theory and theoryof control. Implementation of the results from this researchinto practice has drastically decreased the production costs.Most production processes are highly automated, and the use ofrobots in industry is growing. As far as office, or businessprocesses are concerned, the situation is quite different.Though the office workers and sales personnel have obtainedmuch help from the modern computers, the office and salesprocesses are far behind the production processes on the levelof automation. The computers are used in the office mainly tohelp in performing various activities, e.g., to write a letter,to print an invoice, to complete a transaction, etc. Thecontrol of the business processes in the office remains, to alarge extent, manual. There is a lot to gain if the controlover business processes could be automated, at leastpartially.
The material presented in this thesis is aimed to supportthe following hypothesis: "The ideas worked out in the Mathematical system theory formodeling and controlling physical processes can be successfullyused for modeling and controlling business processes." Oneof the main ideas of mathematical system theory is to considera process as a set of valid trajectories in a state space, andthis idea is the keystone for the thesis. The thesis startswith reformulating the state-oriented approach for the domainof business processes to show what kind of sate space can beused in this domain. First, the approach is introducedinformally by means of an example. Next, a possibleformalization adjusted to the properties of business processesis discussed. Then, experimental evidences that the methodsuggested in the thesis can be used in practice are presented.The suggested method is also compared with other methods ofbusiness process modeling to find out the areas where it hasadvantages over the other methods. In the conclusion, theresults are summarized, and plansfor the future are drawn.
Most of the material included in the thesis has beenpublished and presented at international conferences. Thecontribution of this thesis consists in organizing the materialin support of the main hypothesis.
13
Cunis, Torbjørn. "Modeling, analysis, and control for upset recovery : from system theory to unmanned aircraft flight." Thesis, Toulouse, ISAE, 2019. http://www.theses.fr/2019ESAE0027.
Повний текст джерелаАнотація:
Le travail effectué au cours de cette thèse tente d’apporter des solutions algorithmiques à la problématique de reprise au décrochage d’un aéronef. A travers de nombreux exemples d’application sur des modèles aérodynamiques, le lecteur pourra appréhender les concepts abstraits présentés dans cette thèse. Alors que la capacité pour un aéronef à revenir à une situation nominale après une sortie du domaine de vol est un élément clé pour les systèmes de transport aérien du futur, les recherches menées dans ce cadre sont encore peu nombreuses. Pourtant,un tel dépassement conduit généralement à une perte de contrôle (dénommée LOC-I), que l’Association du Transport Aérien International (IATA) a classé dans la catégorie des « risques les plus élevés pour l’aviation ». Dans un premier temps, nous avons montré que les modèles polynomiaux habituellement utilisés en théorie des systèmes ne représentent pas fidèlement l’aérodynamique d’un modèle d’avion sur l’ensemble de son enveloppe de vol. Nous avons donc tout d’abord montré qu’un modèle polynomial par morceaux représente avec exactitude les coefficients aérodynamiques pour les angles d’attaque faibles et élevés. Nous avons alors pu étendre à cette classe de systèmes, récentes d’étude de bifurcation et d’analyse de stabilité qui utilisent des techniques de programmation semi-définie basées sur la positivité de polynômes (SOS); nous avons notamment appliqué ces résultats au modèle d’avion de transport générique dénommé GTM. Dans le même esprit, nous avons développé un modèle pour un petit aéronef à voilure fixe basé sur des simulations numériques en mécanique des fluides (CFD). Les coefficients dynamiques n’étant pas déterminés en CFD, nous avons identifié le coefficient d’amortissement du tangage en comparant l’analyse de bifurcation et les données de vol, ce qui nous a permis d’étudier à la fois la dynamique et la stabilité du vol en cas de fort décrochage.Des résultats antérieurs ont montré que les techniques SOS étaient prometteuses pour la certification des lois de commande pour des systèmes non-linéaires, cependant sans avoir été appliqués à l’ingénierie aéronautique. En adaptant ces techniques aux modèles polynomiaux par morceaux,nous avons montré qu’il est désormais possible de les utiliser d’une manière précise mais réalisable sur le plan calculatoire. Ensuite, nous avons synthétisé des lois de commandes linéaires et polynomiales pour la récupération d’un fort décrochage. En outre, nous sommes désormais en mesure d’estimer des régions d’attraction pour des modèles polynomiaux par morceaux; pour cela, nous avons proposé un algorithme amélioré pour l’analyse de stabilité locale des systèmes à commutation, tels que ceux qui sont définis par des splines, rendant ainsi notre travail disponible pour l’analyse et la certification futures de modèles d’avion très fidèles.La commande prédictive basée modèle (MPC) s’est avérée être une approche très efficace lorsque la dynamique du système est fortement non linéaire et soumise à des contraintes d’état qui rendent difficile la récupération après le décrochage. Cependant, pour des systèmes réalistes,il est nécessaire de prendre des précautions afin de prouver rigoureusement la stabilité en boucle fermée. En utilisant la technique SOS, nous avons ainsi montré la stabilité d’une stratégie de récupération d’un fort décrochage visant à minimiser la perte d’altitude. Nous avons aussi montré qu’une telle stratégie de commande permet la récupération d’une spirale infernale en utilisant le simulateur GTM.Les résultats de cette thèse sont donc prometteurs et fournissent de nouvelles approches théoriques pour la modélisation, l’analyse de stabilité et le contrôle de la dynamique des futurs aéronefs ainsi que pour le développement et la certification de systèmes de commande de vol visant a prévenir les accidents dus à la perte de contrôleUpset flight dynamics are characterised by unstable, highly nonlinear behaviourof the aircraft aerodynamic system. As upsets often lead to in-flight loss-of-control (LOC-I) accidents,it still poses a severe threat to today’s commercial aviation. Contributing to almost everysecond fatality in civil aviation while representing merely 10% of the total accidents (both fataland nonfatal), the International Air Transport Association has classified LOC-I as the “highestrisk to aviation safety”. Considerable effort has been undertaken in response by academics,manufacturers, commercial airlines, and authorities to predict and prevent LOC-I events as wellas recover from upset conditions into the nominal flight envelope. As result, researchers fromboth aeronautical engineering and system theory have made significant contributions towardsaviation safety; however, approaches from engineering and theory are rather disparate. This thesistherefore focuses on the application and transfer of system theoretical results to engineeringapplications.In particular, we have found simple polynomial models for aircraft dynamics, despite commonin the system theoretical literature, failing to represent full-envelope aerodynamics accurately.Advanced fitting methods such as multi-variate splines, on the other hand, are unsuitable forsome of the proposed functional analysis methods. Instead, a simple piecewise defined polynomialmodel proves to be accurate in fitting the aerodynamic coefficients for low and high angles ofattack. State-of-the-art bifurcation analysis and analysis based on sum-of-squares programmingtechniques are extended for this class of models and applied to a piecewise equations of motionof the Generic Transport Model (GTM). In the same spirit, we develop a model for a small,fixed-wing aircraft based on static continuous fluid dynamics (CFD) simulations. In the lackof dynamic coefficients from CFD, we identify a pitch-damping model comparing bifurcationanalysis and flight data that predicts well dynamics and stability of deep-stall flight.Previous developments in sum-of-squares programming have been promising for the certificationof nonlinear dynamics and flight control laws, yet their application in aeronauticalengineering halted. In combination with piecewise polynomial modeling, we are able to re-applythis technique for analysis in an accurate but computationally feasible manner to verify stablerecovery. Subsequently, we synthesise inherently stable linear and polynomial feedback laws fordeep-stall recovery. We further extend the estimation of regions of attraction for the piecewisepolynomial model towards an improved algorithm for local stability analysis of arbitrary switchingsystems, such as splines, thus making our work available for future analysis and certificationof highly accurate algebraic models.With highly nonlinear dynamics and critical state and input constraints challenging upsetrecovery, model-predictive control (MPC) with receding horizon is a powerful approach. MPCfurther provides a mature stability theory contributing towards the needs for flight control certification.Yet, for realistic control systems careful algebraic or semi-algebraic considerationsare necessary in order to rigorously prove closed-loop stability. Employing sum-of-squares programming,we provide a stability proof for a deep-stall recovery strategy minimising the loss ofaltitude during recovery. We further demonstrate MPC schemes for recovery from spiral andoscillatory spin upsets in an uncertain environment making use of the well-known and freelyavailable high-fidelity GTM desktop simulation.The results of this thesis are thus promising for future system theoretic approaches in modeling,analysis, and control of aircraft upset dynamics for the development and certification offlight control systems in order to prevent in-flight loss-of-control accidents
14
Koch, Patrick N. "Hierarchical modeling and robust synthesis for the preliminary design of large scale complex systems." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/16651.
Повний текст джерела
15
Fanizza, Giovanna. "Modeling and Model Reduction by Analytic Interpolation and Optimization." Doctoral thesis, Stockholm : Engineering sciences, Kungliga Tekniska högskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9125.
Повний текст джерела
16
Bottegal, Giulio. "Modeling, estimation and identification of stochastic systems with latent variables." Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3423358.
Повний текст джерелаАнотація:
The main topic of this thesis is the analysis of static and dynamic models in which some variables, although directly influencing the behavior of certain observables, are not accessible to measurements. These models find applications in many branches of science and engineering, such as control systems, communications, natural and biological sciences and econometrics. It is well-known that models with unaccessible - or latent - variables, usually suffer from a lack of uniqueness of representation. In other words, there are in general many models of the same type describing a given set of observables say, the measurable input-output variables. This is well-known and has been well-studied for a special class of linear models, called state-space models. In this thesis we shall focus on two particular classes of stochastic systems with latent variables: the generalized factor analysis models and errors-in-variables models. For these classes of models there are still some unresolved issues related to non-uniqueness of the representation and clarifying these issues is of paramount importance for their identification. Since mathematical models usually need to be estimated from experimental data, solving the non-uniqueness problem is essential for their use in statistical inference (system identification) from measured data.L’argomento principale di questa tesi è l’analisi di modelli statici e dinamici in cui alcune variabili non sono accessibili a misurazioni, nonostante esse influenzino l’evoluzione di certe osservazioni. Questi modelli trovano applicazione in molte discipline delle scienze e dell’ingegneria, come ad esempio l’automatica, le telecomunicazioni, le scienze naturali, la biologia e l’econometria e sono stati studiati approfonditamente nel campo dell’identificazione dei modelli. E' ben noto che sistemi con variabili inaccessibili - o latenti, spesso soffrono di una mancanza di unicità nella rappresentazione. In altre parole, in generale ci sono molti modelli dello stesso tipo che possono descrivere un dato insieme di osservazioni, come ad esempio variabili misurabili di ingresso-uscita. Questo è ben noto, ed è stato studiato a fondo per una classe speciale di modelli lineari, chiamata modelli a spazio di stato. In questa tesi ci si focalizza su due classi particolari di sistemi stocastici a variabili latenti: i modelli generalized factor analysis e i modelli errors-in-variables. Per queste classi di modelli ci sono ancora alcuni problemi irrisolti legati alla non unicità della rappresentazione e chiarificare questi problemi è di importanza fondamentale per la loro identificazione. Poiché solitamente i modelli matematici necessitano ti essere stimati da dati sperimentali, è essenziale risolvere il problema della non unicità per il loro utilizzo nell’inferenza statistica (identificazione di modelli) da dati misurati.
17
Heinen, Garrett David. "Modeling and Charging Control of a Lithium Ion Battery System for Solar Panels." DigitalCommons@CalPoly, 2017. https://digitalcommons.calpoly.edu/theses/1745.
Повний текст джерелаАнотація:
The advancement in solar panel and battery technology makes them useful for energy supply and storage. This thesis involves the modeling and charging control of a lithium ion battery system for solar panels. The proposed model is based on the parameters and characteristics of a realistic battery and solar panel system; and the hybrid control approach combines the advantages of the adaptive incremental conductance method and the perturb and observe method to track the maximum power point of the solar panel for charging the battery unit. Computer simulation results demonstrate that this proposed approach offers a faster convergence rate than the adaptive incremental conductance method, and less steady-state error than the perturb and observe method.
18
Biroscak, Brian J. "Use of System Dynamics Modeling to Explicate the Theory-of-Change of a Social Marketing Innovation." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5184.
Повний текст джерелаАнотація:
Community coalitions are an important part of the public health milieu and thus subject to many of the same external pressures as public health organizations--including changes in required strategic orientation. Many funding agencies have shifted their funding agenda from program development to policy change. Thus, the Florida Prevention Research Center created the Community-Based Prevention Marketing for Policy Development framework to teach community coalitions how to apply social marketing to policy change. The dissertation research reported here was designed to explicate the framework's theory-of-change. The research question was: "What are the linkages and connections between CBPM inputs, activities, immediate outcomes, intermediate outcomes, and ultimate impacts?" The author implemented a case study design, with the case being a normative community coalition. The study adhered to a well-developed series of steps for system dynamics modeling.
Results from model simulations show how gains in performance depend on a community coalition's initial culture and initial efficiency, and that only the most efficient coalitions may see benefits in coalition performance from implementing Community-Based Prevention Marketing for Policy Development. Theoretical implications for social marketers--e.g., real-world example of how to work `upstream'--and system dynamics modelers--e.g., application of generic structures--are discussed. Practical implications for the framework's developers--namely, the importance of managing the early expectations of framework adopters--are discussed as well.
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Park, Seung In. "Modeling Social Group Interactions for Realistic Crowd Behaviors." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/19297.
Повний текст джерелаАнотація:
In the simulation of human crowd behavior including evacuation planning, transportation management, and safety engineering in architecture design, the development of pedestrian model for higher behavior fidelity is an important task. To construct plausible facsimiles of real crowd movements, simulations should exhibit human behaviors for navigation, pedestrian decision-making, and social behaviors such as grouping and crowding. The research field is quite mature in some sense, with a large number of approaches that have been proposed to path finding, collision avoidance, and visually pleasing steering behaviors of virtual humans. However, there is still a clear disparity between the variety of approaches and the quality of crowd behaviors in simulations.Many social science field studies inform us that crowds are typically composed of multiple social groups (James, 1953; Coleman and James, 1961; Aveni, 1977). These observations indicate that one component of the complexity of crowd dynamics emerges from the presence of various patterns of social interactions within small groups that make up the crowd. Hence, realism in a crowd simulation may be enhanced when virtual characters are organized in multiple social groups, and exhibit human-like coordination behaviors.
Motivated by the need for modeling groups in a crowd, we present a multi-agent model for large crowd simulations that incorporates socially plausible group behaviors. A computational model for multi-agent coordination and interaction informed by well- established Common Ground theory (Clark, 1996; Clark and Brennan, 1991) is proposed. In our approach, the task of navigation in a group is viewed as performing a joint activity which requires maintaining a state of common ground among group members regarding walking strategies and route choices. That is, group members communicate with, and adapt their behaviors to each other in order to maintain group cohesiveness while walking. In the course of interaction, an agent may present gestures or other behavioral cues according to its communicative purpose. It also considers the spatiotemporal conditions of the agent-group\'s environment in which the agent interacts when selecting a kind of motions.
With the incorporation of our agent model, we provide a unified framework for crowd simulation and animation which accommodates high-level socially-aware behavioral realism of animated characters. The communicative purpose and motion selection of agents are consistently carried through from simulation to animation, and a resulted sequence of animated character behaviors forms not merely a chain of reactive or random gestures but a socially meaningful interactions.
We conducted several experiments in order to investigate the impact of our social group
interaction model in crowd simulation and animation. By showing that group communicative behaviors have a substantial influence on the overall distribution of a crowd, we demonstrate the importance of incorporating a model of social group interaction into multi-agent simulations of large crowd behaviors. With a series of perceptual user studies, we show that our model produces more believable behaviors of animated characters from the viewpoint of human observers.
Ph. D.
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Thompson, Kelsie. "Using Video Modeling to Improve Staff Implementation of the PEAK Relational Training System." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7585.
Повний текст джерелаАнотація:
Evidence suggests that the Promoting the Emergence of Advanced Knowledge Relational Training System (PEAK) is an effective method of providing verbal behavior training to individuals with developmental disabilities, and previous research indicates that BST can be used to train staff in its implementation. Video modeling is a modification to BST that can decrease the amount of resources necessary to provide instruction without limiting the effectiveness of the training. This study evaluated the effectiveness of using video modeling for teaching direct care staff how to implement the Promoting the Emergence of Advanced Knowledge Relational Training System (PEAK) using a multiple baseline across participants design. All participants showed improvement in PEAK implementation with video modeling treatment; one required the addition of a checklist to achieve mastery. Implications for further research are discussed.
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Lee, Timothy J. "CHITRA93 : a tool to analyze system behavior by visualizing and modeling ensembles of traces /." Master's thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-10242009-020057/.
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Black, Derek J. "Development and feasibility of economical hardware and software in control theory application." Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/38170.
Повний текст джерелаАнотація:
Master of ScienceDepartment of Mechanical and Nuclear Engineering
Dale E. Schinstock
Control theory is the study of feedback systems, and a methodology investigated by many engineering students throughout most universities. Because of control theory's broad and interdisciplinary nature, it necessitates further study by application through experimental learning and laboratory practice. Typically, the hardware used to connect the theoretical aspects of controls to the practical can be expensive, big, and time consuming to the students and instructors teaching on the equipment. Alternatively, using cheaper sensors and hardware, such as encoders and motor drivers, can obfuscate the collected data in a way that creates a disconnect between developed theoretical models and actual system results. This disconnect can dissuade the idea that systems can and will follow a modeled behavior. This thesis attempts to assess the feasibility of a piece of laboratory apparatus named the NERMLAB. Multiple experiments will be conducted on the NERMLAB system and compared against time-tested hardware to demonstrate the practicality of the NERMLAB system in control theory application.
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Layshot, Nicholas Joseph. "MODELING OF A GYRO-STABILIZED HELICOPTER CAMERA SYSTEM USING NEURAL NETWORKS." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/421.
Повний текст джерелаАнотація:
On-board gimbal systems for camera stabilization in helicopters are typically based on linear models. Such models, however, are inaccurate due to system nonlinearities and complexities. As an alternative approach, artificial neural networks can provide a more accurate model of the gimbal system based on their non-linear mapping and generalization capabilities.
This thesis investigates the applications of artificial neural networks to model the inertial characteristics (on the azimuth axis) of the inner gimbal in a gyro-stabilized multi-gimbal system. The neural network is trained with time-domain data obtained from gyro rate sensors of an actual camera system. The network performance is evaluated and compared with measured data and a traditional linear model. Computer simulation results show the neural network model fits well with the measured data and significantly outperforms a traditional model.
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Warshawsky, David. "A system of systems flexibility framework: A method for evaluating designs that are subjected to disruptions." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54277.
Повний текст джерелаАнотація:
As systems become more interconnected, the focus of engineering design must shift
to include consideration for systems of systems (SoS) e ects. As the focus shifts from
singular systems to systems of systems, so too must the focus shift from performance
based analysis to an evaluation method that accounts for the tendency of such large
scale systems to far outlive their original operational environments and continually
evolve in order to adapt to the changes. It is nearly impossible to predict the nature
of these changes, therefore the rst focus of this thesis is the measurement of
the
exibility of the SoS and its ability to evolve and adapt. Flexibility is measured
using a combination of network theory and a discrete event simulation, therefore,
the second focus is the development of a simulation environment that can also measure
the system's performance for baseline comparisons. The results indicate that
simulated
exibility is related to the performance and cost of the SoS and is worth
measuring during the design process. The third focus of this thesis is to reduce the
computational costs of SoS design evaluation by developing heuristics for
exibility.
This was done by developing a network model to correspond with the discrete event
simulation and evaluating network properties using graph theory. It was shown that
the network properties can correlate with simulated
exibility. In such cases it was
shown that the heuristics could be used in connection with an evolutionary algorithm
to rapidly search the design space for good solutions. The entire methodology was
demonstrated on a multi-platform maintenance planning problem in connection with
the Navy Hardware Open System Technologies initiative.
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Khan, Imran. "Hajj crowd management: Discovering superior performance with agent-based modeling and queueing theory." Arabian Journals of Business and Management Review, 2012. http://hdl.handle.net/1993/13698.
Повний текст джерелаАнотація:
The thesis investigates how Agent-Based Modeling and Simulation (ABMS) and Queueing Theory (QT) techniques help manage mass gathering (MG) crowds. The techniques are applied to Hajj MG, which is one of the most complex annual MG, with a focus on its challenging Tawaf ritual. The objective is to develop a Tawaf Decision Support System (DSS) to better understand Tawaf crowd dynamics and discover decisions that lead to superior performance. TawafSIM is an ABMS model in the DSS, which simulates macro-level Tawaf crowd dynamics through micro-level pilgrim modeling to explore the impact of crowd characteristics, facility layout, and management preferences on emergent crowd behaviours with respect to throughput, satisfaction, health, and safety. Whereas, TawafQT is a QT model in the DSS to explore the impact of pilgrim arrival rate and Tawaf throughput on expected arrival, departure, and waiting times along with average queue length in the Tawaf waiting area.
The thesis provides several contributions, including the following. First, it is the only Tawaf research to use a hybrid ABMS and QT approach. Second, TawafSIM is a comprehensive Tawaf simulator. It incorporates features for pilgrim characteristics, facility design, and management preferences. It calculates eight metrics for Tawaf performance, which includes one for throughput, three for satisfaction, one for health, and three for safety. It is the only Tawaf simulator to estimate satisfaction and spread of infectious disease. It conducts 42 simulation experiments in 12 categories. It generates observations for emergent, tipping point, expected, and counter intuitive behaviours. It recommends a default scenario as the best decision along with a small subset of alternative scenarios, which provide above average Tawaf performance. It generates a Tawaf Crowd Management Guide to better understand Tawaf crowd dynamics and how to pursue above average Tawaf performance under different conditions. Third, TawafQT is the only study of the Tawaf waiting area. It uses an accurate queueing model with finite source, single service, and PH type distribution, which is not only applicable to the Tawaf and other Hajj related queueing systems but also to any queueing system, which has finite population and single service characteristics.
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Garvey, Matthew Sidney. "Performance Analysis of a Dual-Use Secure Radarcomm System in Non-Line-of-Sight Environments: Theory & Modeling." Miami University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=miami1596212392792427.
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Robuschi, Camilla. "L'estetico quale strumento di modellizzazione nella prospettiva della biosemiotica." Doctoral thesis, Università degli studi di Trento, 2022. https://hdl.handle.net/11572/355841.
Повний текст джерелаАнотація:
Il presente lavoro di ricerca vuole essere un contributo all’elaborazione di una teoria della modellizzazione estetica. L’idea di estetico che verrà sviluppata è solo in ultima istanza incentrata sulle opere d’arte, le quali saranno prese in considerazione nei termini di prodotti simbolici costituitivi della sfera culturale umana. Diversamente, nella prospettiva che vogliamo presentare, l’estetico sarebbe parte di un processo ecosistemico e di modellizzazione che coinvolge a vari livelli anche gli altri esseri viventi. L’estetico, ossia, sarebbe uno strumento utile alla creazione di specifici modelli che consentirebbero l’interfaccia con l’ambiente, dove l’obiettivo centrale del presente studio è quello di individuare il tipo di modelli che l’estetico permette di creare e il processo che conduce alla loro costituzione. La modellizzazione estetica, dunque, sarebbe tutt’altro che un comportamento accessorio o di sfondo, bensì uno strumento utile alla sopravvivenza che nell’essere umano trova la sua massima espressione nel simbolico quale capacità di produrre opere d’arte. Sotto questo aspetto, una teoria della modellizzazione estetica permette di superare quei binarismi che per secoli hanno impedito di studiare l’estetico in qualità di processo unitario e complesso. Il comportamento estetico sarebbe infatti una delle manifestazioni più evidenti della continuità tra cultura e natura, verbale e non verbale, soggetto e agente.
Al fine di condurre un’indagine di questo tipo, ritengo utile utilizzare gli strumenti offerti dal campo di studi della biosemiotica, i quali permettono una visione biologica e relazionale dei fenomeni estetici. Gli obiettivi principali sono quelli di porre le basi per un ripensamento dell’estetica tradizionale e di riconsiderare il posizionamento dell’uomo all’interno della natura tramite l’analisi del comportamento estetico.
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Zobaer, M. S. "Physiology-Based Modeling of Sleep and Wake Phenomena in the Human Brain." Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/18643.
Повний текст джерелаАнотація:
The brain is a complex system with connections of interacting subsystems, feedback loops operating at different timescales. In this thesis, the focus is on the brain dynamics of sleep-wake states and related phenomena. A general overview of the thesis is given in Ch. 1, to provide the physiological background of the relevant brain dynamics, the electrical activity of the brain, and the phenomena of the circadian rhythm. The corticothalamic neural field model successfully explains different sleep-wake stages. The circadian pacemaker model successfully describes the circadian rhythm modulated by light exposure. Chapter 2 discusses two electroencephalography (EEG) phenomena: (a) spontaneous K-complexes (KCs) with spindles and (b) the evoked response potential (ERP). It is shown here that both KCs and ERPs can be unified within a common theoretical framework. Chapter 3 presents the model ERPs within the overall corticothalamic stability zone in a reduced three-dimensional parameter space for normal (near critical) states, and far from the critical states using the same model presented in Ch. 2. Both theoretical time series and wavelet transform are used to characterize model ERPs. In Ch. 4, a basic circadian model is improved to account for the effects of the different light spectrum and the spectral sensitivity function of the eyes. The model results also are shown to reproduce the circadian phase responses as found in the experiments. This thesis is summarized in Ch. 5 which suggests an overall framework for the two physiology-based models including the outcomes, applications, the possibilities for future work, and improvements of the models. This thesis also includes an appendix to define systematically the physical and physiological properties of lights and photoreceptor systems in the eyes to minimize confusion in the literature between the mathematical and biological models.
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Osman, Esam. "Developing strategic information system planning model in Libya organisations." Thesis, University of Plymouth, 2012. http://hdl.handle.net/10026.1/1173.
Повний текст джерелаАнотація:
This quantitative research study investigated the impact of organisational context on the process and success of strategic IS planning (SISP) in post-implementation information systems in Libyan organisations. A set of direct and indirect relationships were investigated in the research model. The organisational context presented as a contingent situational variable mediated by SISP process and predicted by SISP success (the criterion variable). The causality of the relationship set was developed from the contingency theory of information systems and supported by fit models in strategic management research. The study deployed multivariate analysis represented in the structural equation modelling (SEM) to develop robust construct measurements and analyse data collected from executives responsible for information systems planning in both public and private Libyan organisations. Multi-dimensional multi-items constructs were used in the path analysis model after they were extensively validated. The path analysis model represented as mediation model, where hypothesise suggest that SISP context has an impact SISP success, through the influence of the SISP process. In the model, four dimensions of the SISP context construct were found to have a significant impact on SISP success directly and indirectly through the SISP process. Two of these dimensions are components of the leadership orientation construct, namely “Creative and Controlling” leadership. The other two dimensions are “Organisation centralisation structure and the Riskiness of organisation strategies”. The environmental uncertainty and planning resource constructs were found to have no impact on SISP success in Libyan organisations. Furthermore, this study validated six out of seven dimensions of SISP process construct measurement; only five exhibited acceptable fit level in the path analysis model and all were affected by the SISP context. However, just three out of five SISP process constructs had an impact on SISP success namely “Comprehensiveness, Focus and Intuition planning process”. Different SISP processes were associated with different levels of SISP success, “Intuition” was the most effective SISP process approach. The second most effective SISP process approach was the “Focus on innovation”, followed by “Limited comprehensiveness”. The SISP success measured by the fulfilment of key objectives that has three measurements constructs namely “Analysis, Alignment, and Cooperation”. The research suggest that under the effect of organisation context the most successful SISP produced by (CIO, CEO, or top executives) who rely less on personal judgment, focus more on innovation rather than control and limit their comprehensiveness of information systems planning process.
30
Senturk, Sertan. "Computational modeling of improvisation in Turkish folk music using Variable-Length Markov Models." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42761.
Повний текст джерелаАнотація:
The thesis describes a new database of uzun havas, a non-metered structured improvisation form in Turkish folk music, and a system, which uses Variable-Length Markov Models (VLMMs) to predict the melody in the uzun hava form. The database consists of 77 songs, encompassing 10849 notes, and it is used to train multiple viewpoints, where each event in a musical sequence are represented by parallel descriptors such as Durations and Notes. The thesis also introduces pitch-related viewpoints that are specifically aimed to model the unique melodic properties of makam music. The predictability of the system is quantitatively evaluated by an entropy based scheme. In the experiments, the results from the pitch-related viewpoints mapping 12-tone-scale of Western classical theory and 17 tone-scale of Turkish folk music are compared. It is shown that VLMMs are highly predictive in the note progressions of the transcriptions of uzun havas. This suggests that VLMMs may be applied to makam-based and non-metered musical forms, in addition to Western musical styles. To the best of knowledge, the work presents the first symbolic, machine-readable database and the first application of computational modeling in Turkish folk music.
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Maertens, Miet. "Economic modeling of agricultural land-use patterns in forest frontier areas : theory, empirical assessment and policy implications for Central Sulawesi, Indonesia /." Berlin : dissertation.de, 2003. http://www.gbv.de/dms/zbw/380100983.pdf.
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Papp, John Laszlo. "SIMULATION OF TURBULENT SUPERSONIC SEPARATED BASE FLOWS USING ENHANCED TURBULENCE MODELING TECHNIQUES WITH APPLICATION TO AN X-33 AEROSPIKE ROCKET NOZZLE SYSTEM." University of Cincinnati / OhioLINK, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=ucin962118912.
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Yang, Xige. "MATHEMATICAL MODELS OF PATTERN FORMATION IN CELL BIOLOGY." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1542236214346341.
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Gastin, Paul. "Un modele distribue." Paris 7, 1987. http://www.theses.fr/1987PA077072.
Повний текст джерелаАнотація:
Le modele presente s'inspire de la theorie des langages. Son originalite est le refus de representer le parallelisme par intercalage des actions concurrentes. Les idees fortes reprises dans ce travail sont issues des langages csp et estelle. Il s'agit principalement de l'independance totale des processus en dehors des synchronisations, ces dernieres etant des rendez-vous. Un element du modele distribue sera en consequence un vecteur d'histoires (un four chaque processus) et un ensemble de synchronisations
35
Grombein, Thomas [Verfasser]. "Gravity forward modeling with a tesseroid-based Rock-Water-Ice approach – Theory and applications in the context of the GOCE mission and height system unification / Thomas Grombein." Karlsruhe : KIT Scientific Publishing, 2017. http://www.ksp.kit.edu.
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Yin, Weiwei. "The role and regulatory mechanisms of nox1 in vascular systems." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44833.
Повний текст джерелаАнотація:
As an important endogenous source of reactive oxygen species (ROS), NADPH oxidase 1 (Nox1) has received tremendous attention in the past few decades. It has been identified to play a key role as the initial "kindle," whose activation is crucial for amplifying ROS production through several propagation mechanisms in the vascular system. As a consequence, Nox1 has been implicated in the initiation and genesis of many cardiovascular diseases and has therefore been the subject of detailed investigations.
The literature on experimental studies of the Nox1 system is extensive. Numerous investigations have identified essential features of the Nox1 system in vasculature and characterized key components, possible regulatory signals and/or signaling pathways, potential activation mechanisms, a variety of Nox1 stimuli, and its potential physiological and pathophysiological functions. While these experimental studies have greatly enhanced our understanding of the Nox1 system, many open questions remain regarding the overall functionality and dynamic behavior of Nox1 in response to specific stimuli. Such questions include the following. What are the main regulatory and/or activation mechanisms of Nox1 systems in different types of vascular cells? Once Nox1 is activated, how does the system return to its original, unstimulated state, and how will its subunits be recycled? What are the potential disassembly pathways of Nox1? Are these pathways equally important for effectively reutilizing Nox1 subunits? How does Nox1 activity change in response to dynamic signals? Are there generic features or principles within the Nox1 system that permit optimal performance?
These types of questions have not been answered by experiments, and they are indeed quite difficult to address with experiments. I demonstrate in this dissertation that one can pose such questions and at least partially answer them with mathematical and computational methods. Two specific cell types, namely endothelial cells (ECs) and vascular smooth muscle cells (VSMCs), are used as "templates" to investigate distinct modes of regulation of Nox1 in different vascular cells. By using a diverse array of modeling methods and computer simulations, this research identifies different types of regulation and their distinct roles in the activation process of Nox1. In the first study, I analyze ECs stimulated by mechanical stimuli, namely shear stresses of different types. The second study uses different analytical and simulation methods to reveal generic features of alternative disassembly mechanisms of Nox1 in VSMCs. This study leads to predictions of the overall dynamic behavior of the Nox1 system in VSMCs as it responds to extracellular stimuli, such as the hormone angiotensin II. The studies and investigations presented here improve our current understanding of the Nox1 system in the vascular system and might help us to develop potential strategies for manipulation and controlling Nox1 activity, which in turn will benefit future experimental and clinical studies.
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Augeraud, Michel. "Systel-D : un modèle et une méthode d'analyse et de conception des systèmes de communication prenant en compte leurs aspects dynamiques." Poitiers, 1989. http://www.theses.fr/1989POIT2263.
Повний текст джерелаАнотація:
L'objectif est la definition d'un modele et d'une methode d'etude au niveau logique d'un systeme de communication prenant en compte l'ensemble des aspects qui caracterisent les liaisons de communication et plus particulierement leur aspect dynamique. Le modele repose, pour traduire l'aspect dynamique, sur une representation discrete du fonctionnement observe a un niveau macroscopique
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Zhang, Aixiu (Monica). "Transactional Distance in Web-based College Learning Environments: Toward Measurement and Theory Construction." VCU Scholars Compass, 2003. http://scholarscompass.vcu.edu/etd_retro/94.
Повний текст джерелаАнотація:
Michael Moore's theory of transactional distance, developed in the age of correspondence schools, contributed greatly to theory building in distance education. The theory needs revision, however, when applied to web-based learning environments, specifically by defining transactional distance to include students' relationships with other elements in the learning environment that prohibit their active engagement with learning. The new theoretical model of transactional distance has four dimensions: transactional distance between student and student (TDSS), transactional distance between student and teacher (TDST), transactional distance between student and content (TDSC), and transactional distance between student and interface: online course management system (TDSI). A preliminary item pool of more than 200 items to measure the constructs of TD, TDST, TDSS, TDSC, and TDSI was generated and sent to a panel of experts for review. Items that the reviewers considered weak or very weak in terms of relevance to the constructs and/or clarity and conciseness were eliminated. After a pilot test and further revisions, the proposed scale of transactional distance was administered to a sample of 100 college students. Confirmatory factor analyses and exploratory analyses indicated that the measurement models, especially after modifications, possessed good fit for the data, and the modified scales possessed factorial validity. Reliability analyses indicated that the scales possessed strong internal consistency, with Cronbach alpha coefficients ranging from 0.8169 to 0.9530. Structural equation modeling procedures tested for the causal relationship between the four dimensions and students' general sense of transactional distance in web-based courses. Results indicate that the proposed model of transactional distance is acceptable. The strongest factor that affected students' sense of transactional distance and engagement with learning was found to be transactional distance between student and students (TDSS), followed by transactional distance between student and teacher (TDST), and then by transactional distance between student and content (TDSC). The findings have implications for the development of a revised theory of transactional distance in online education, and provide strong support for constructivist learning theories and social learning theories, reinforcing the importance of establishing learning communities in online learning environments.
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Singh, Minerva. "Design of a system to support policy formulation for sustainable biofuel production." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:db054d43-6359-45cd-af82-a71abd2b288b.
Повний текст джерелаАнотація:
The increased demand for biofuels is expected to put additional strain on the available agricultural resources while at the same time causing environmental degradation. Hence, new energy policies need to be formulated and implemented in order to meet global energy needs while reducing the impact of biofuels farming and production. This research focuses on proving a decision support system which can aid the formulation of policies for the sustainable biofuel production. The system seeks to address policy formulation that requires reconciliation of the qualitative aspects of decision making (such as stakeholder’s viewpoints) with quantitative data, which often may be imprecise. To allow this, based on: Fuzzy logic and Multi Criteria Decision Making (MCDM) in the form of Analytical Hierarchy Process (AHP). Using these concepts, three software functionalities, “Options vs. Fuzzy Criteria Matrix”, “Analytical Hierarchy Process” and “Fuzzy AHP” were developed. These were added within the framework of pre-existing base software, Compendium (developed by the Open University, UK). A number of case study based models have been investigated using the software. These models made use of data from the Philippines and India in order to pinpoint suitable land and crop options for these countries. The models based on AHP and Fuzzy AHP were very successful in identifying suitable crop options for India by capturing both the stakeholder viewpoints and quantitative data. The software functionalities are very effective in scenario planning and selection of policies that would be beneficial in achieving a desired future scenario. The models further revealed that the newly developed software correctly identified many of the important issues in a consistent manner.
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Grombein, Thomas [Verfasser], and B. [Akademischer Betreuer] Heck. "Gravity forward modeling with a tesseroid-based Rock-Water-Ice approach – Theory and applications in the context of the GOCE mission and height system unification / Thomas Grombein ; Betreuer: B. Heck." Karlsruhe : KIT-Bibliothek, 2017. http://d-nb.info/1130246566/34.
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Kesting, Arne. "Microscopic Modeling of Human and Automated Driving: Towards Traffic-Adaptive Cruise Control." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1204804167720-57734.
Повний текст джерелаАнотація:
The thesis is composed of two main parts. The first part deals with a microscopic traffic flow theory. Models describing the individual acceleration, deceleration and lane-changing behavior are formulated and the emerging collective traffic dynamics are investigated by means of numerical simulations. The models and simulation tools presented provide the methodical prerequisites for the second part of the thesis in which a novel concept of a traffic-adaptive control strategy for ACC systems is presented. The impact of such systems on the traffic dynamics can solely be investigated and assessed by traffic simulations. The focus is on future adaptive cruise control (ACC) systems and their potential applications in the context of vehicle-based intelligent transportation systems. In order to ensure that ACC systems are implemented in ways that improve rather than degrade traffic conditions, the thesis proposes an extension of ACC systems towards traffic-adaptive cruise control by means of implementing an actively jam-avoiding driving strategy. The newly developed traffic assistance system introduces a driving strategy layer which modifies the driver's individual settings of the ACC driving parameters depending on the local traffic situation. Whilst the conventional operational control layer of an ACC system calculates the response to the input sensor data in terms of accelerations and decelerations on a short time scale, the automated adaptation of the ACC driving parameters happens on a somewhat longer time scale of, typically, minutes. By changing only temporarily the comfortable parameter settings of the ACC system in specific traffic situations, the driving strategy is capable of improving the traffic flow efficiency whilst retaining the comfort for the driver. The traffic-adaptive modifications are specified relative to the driver settings in order to maintain the individual preferences. The proposed system requires an autonomous real-time detection of the five traffic states by each ACC-equipped vehicle. The formulated algorithm is based on the evaluation of the locally available data such as the vehicle's velocity time series and its geo-referenced position (GPS) in conjunction with a digital map. It is assumed that the digital map is complemented by information about stationary bottlenecks as most of the observed traffic flow breakdowns occur at these fixed locations. By means of a heuristic, the algorithm determines which of the five traffic states mentioned above applies best to the actual traffic situation. Optionally, inter-vehicle and infrastructure-to-car communication technologies can be used to further improve the accuracy of determining the respective traffic state by providing non-local information. By means of simulation, we found that the automatic traffic-adaptive driving strategy improves traffic stability and increases the effective road capacity. Depending on the fraction of ACC vehicles, the driving strategy "passing a bottleneck" effects a reduction of the bottleneck strength and therefore delays (or even prevents) the breakdown of traffic flow. Changing to the driving mode "leaving the traffic jam" increases the outflow from congestion resulting in reduced queue lengths in congested traffic and, consequently, a faster recovery to free flow conditions. The current travel time (as most important criterion for road users) and the cumulated travel time (as an indicator of the system performance) are used to evaluate the impact on the quality of service. While traffic congestion in the reference scenario was completely eliminated when simulating a proportion of 25% ACC vehicles, travel times were significantly reduced even with much lower penetration rates. Moreover, the cumulated travel times decreased consistently with the increase in the proportion of ACC vehiclesIn der Arbeit wird ein neues verkehrstelematisches Konzept für ein verkehrseffizientes Fahrverhalten entwickelt und als dezentrale Strategie zur Vermeidung und Auflösung von Verkehrsstaus auf Richtungsfahrbahnen vorgestellt. Die operative Umsetzung erfolgt durch ein ACC-System, das um eine, auf Informationen über die lokale Verkehrssituation basierende, automatisierte Fahrstrategie erweitert wird. Die Herausforderung bei einem Eingriff in das individuelle Fahrverhalten besteht - unter Berücksichtigung von Sicherheits-, Akzeptanz- und rechtlichen Aspekten - im Ausgleich der Gegensätze Fahrkomfort und Verkehrseffizienz. Während sich ein komfortables Fahren durch große Abstände bei geringen Fahrzeugbeschleunigungen auszeichnet, erfordert ein verkehrsoptimierendes Verhalten kleinere Abstände und eine schnellere Anpassung an Geschwindigkeitsänderungen der umgebenden Fahrzeuge. Als allgemeiner Lösungsansatz wird eine verkehrsadaptive Fahrstrategie vorgeschlagen, die ein ACC-System mittels Anpassung der das Fahrverhalten charakterisierenden Parameter umsetzt. Die Wahl der Parameter erfolgt in Abhängigkeit von der lokalen Verkehrssituation, die auf der Basis der im Fahrzeug zur Verfügung stehenden Informationen automatisch detektiert wird. Durch die Unterscheidung verschiedener Verkehrssituationen wird ein temporärer Wechsel in ein verkehrseffizientes Fahrregime (zum Beispiel beim Herausfahren aus einem Stau) ermöglicht. Machbarkeit und Wirkungspotenzial der verkehrsadaptiven Fahrstrategie werden im Rahmen eines mikroskopischen Modellierungsansatzes simuliert und hinsichtlich der kollektiven Verkehrsdynamik, insbesondere der Stauentstehung und Stauauflösung, auf mehrspurigen Richtungsfahrbahnen bewertet. Die durchgeführte Modellbildung, insbesondere die Formulierung eines komplexen Modells des menschlichen Fahrverhaltens, ermöglicht eine detaillierte Analyse der im Verkehr relevanten kollektiven Stabilität und einer von der Stabilität abhängigen stochastischen Streckenkapazität. Ein tieferes Verständnis der Stauentstehung und -ausbildung wird durch das allgemeine Konzept der Engstelle erreicht. Dieses findet auch bei der Entwicklung der Strategie für ein stauvermeidendes Fahrverhalten Anwendung. In der Arbeit wird die stauvermeidende und stauauflösende Wirkung eines individuellen, verkehrsadaptiven Fahrverhaltens bereits für geringe Ausstattungsgrade nachgewiesen. Vor dem Hintergrund einer zu erwartenden Verbreitung von ACC-Systemen ergibt sich damit eine vielversprechende Option für die Steigerung der Verkehrsleistung durch ein teilautomatisiertes Fahren. Der entwickelte Ansatz einer verkehrsadaptiven Fahrstrategie ist unabhängig vom ACC-System. Er erweitert dessen Funktionalität im Hinblick auf zukünftige, informationsbasierte Fahrerassistenzsysteme um eine neue fahrstrategische Dimension. Die lokale Interpretation der Verkehrssituation kann neben einer verkehrsadaptiven ACC-Regelung auch der Entwicklung zukünftiger Fahrerinformationssysteme dienen
42
Leontas, Angela Zoi. "Modeling queueing systems." CSUSB ScholarWorks, 2006. https://scholarworks.lib.csusb.edu/etd-project/3101.
Повний текст джерелаАнотація:
The thesis introduces the theory of queueing systems and demonstrates its applicability to real life problems. It discusses (1) Markovian property and measures of effectiveness with exponential interarrival and service times; (2) Erlang service times, and a single server; (3) different goodness-of-fit tests that can be used to determine whether the exponential distribution is appropriate for a given set of data. A single server queueing system with exponential interarrival times and Erlang service times is simulated using Visual Basic for Applications (VBA).
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Zaini, Raafat Mahmoud. "Modeling Manifest and Latent Structures in a University: Understanding Resources and Dissent Dynamics." Digital WPI, 2017. https://digitalcommons.wpi.edu/etd-dissertations/435.
Повний текст джерелаАнотація:
Using modeling and computer simulation, this research focuses on studying two different views to organizational design and their implications for performance in the context of academic institutions. One view represents the manifest structure that includes resources (students, faculty, administration, facilities, finances, partners, donors, etc.); the other view represents the latent structure that focuses on dissent. The dissertation addresses the following two questions; 1. What are the tangible dynamic interdependencies constituting the manifest structure within academic institutions and their impact on performance? 2. What is the impact of the latent structures composed of intangible organizational processes, especially dissent, on performance? The dissertation proposes generic system dynamics simulation models untangling the complexity of the topic by tackling various slices of the problem in separate papers. The models are based on three different theoretical frameworks addressing resources and their composition, dissent, and stakeholder engagement. It is observed that while both the manifest and the latent parts of the university organization impact its performance, the latent part, being invisible, is often ignored. In the long run, the influence of the latent part of the organization can slowly but seriously compromise intangible performances components like quality, reputation, and attractiveness. When the manifest part of the organization is dysfunctional, its tangible performance rapidly suffers. The damage control policies will often impact the latent organizational performance leading the institution into a vicious cycle. The presence of time delays in this framework may create an oscillatory behavior that might modulate a growth or decline trend. Performance measures addressing intangible performance components must be factored into the organizational design since faculty, students, and other stakeholders are not only driven by financial rewards, but also by the organizational environment. The research, besides addressing the important question of the role of latent elements in organization design and demonstrating this can be done using system dynamics modeling and computer simulation, should also be of value to the design and management of higher education institutions.
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Francis, John Charles. "Qualitative system theory : a systems approach to modelling complex physical processes." Thesis, Heriot-Watt University, 1986. http://hdl.handle.net/10399/1080.
Повний текст джерела
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Boldt, Frank. "A Framework for Modeling Irreversible Processes Based on the Casimir Companion." Doctoral thesis, Universitätsbibliothek Chemnitz, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-145179.
Повний текст джерелаАнотація:
Thermodynamic processes in finite time are in general irreversible. But there are chances to avoid irreversibility. For instance, there are canonical ensembles of special quantum systems with a given probability distribution describing the likelihood to find the system at time t=0 in a particular state with energy E_i(0), which can be controlled in a specific way, such that the initial probability distribution is recovered at the end of the process (t=T), but the state energies did change, hence E_i(0) is not equal to E_i(T). This allows to change thermodynamic quantities (expectation values) adiabatically, reversibly and in finite time. Such special processes are called Shortcuts to Adiabaticity. The presented thesis analyzes the origin of these shortcuts utilizing special Hamiltonian systems with dynamical algebra. Their main feature is to provide canonical invariance, which means a canonical ensemble stays canonical under Hamiltonian dynamics. This invariance carried by the dynamical algebra will be discussed using Lie group theory. In addition, the persistence of the dynamical algebra with respect to calculating expectation values will be deduced. This allows to benefit from all intrinsic symmetries within the discussion of ensemble trajectories. In consequence, these trajectories will evolve under Hamiltonian dynamics on a specific manifold given by the so-called Casimir companion. In addition, the deformation of this manifold due to non-Hamiltonian (dissipative) dynamics will be discussed, which allows to present a framework for modeling irreversible processes based on Hamiltonian systems with dynamical algebra. An application of this framework based on the parametric harmonic oscillator will be presented by determining time-optimal controls for transitions between two equilibrium as well as between non-equilibrium and equilibrium states. The latter one will lead to time-optimal equilibration strategies for a statistical ensemble of parametric harmonic oscillatorsThermodynamische Prozesse in endlicher Zeit sind im Allgemeinen irreversibel. Es gibt jedoch Möglichkeiten, diese Irreversibilität zu umgehen. Ein kanonisches Ensemble eines speziellen quantenmechanischen Systems kann zum Beispiel auf eine ganz spezielle Art und Weise gesteuert werden, sodass nach endlicher Zeit T wieder eine kanonische Besetzungverteilung hergestellt ist, sich aber dennoch die Energie des Systems geändert hat (E(0) ungleich E(T)). Solche Prozesse erlauben das Ändern thermodynamischer Größen (Ensemblemittelwerte) der erwähnten speziellen Systeme in endlicher Zeit und auf eine adiabatische und reversible Art. Man nennt diese Art von speziellen Prozessen Shortcuts to Adiabaticity und die speziellen Systeme hamiltonsche Systeme mit dynamischer Algebra. Die vorliegende Dissertation hat zum Ziel den Ursprung dieser Shortcuts to Adiabaticity zu analysieren und eine Methodik zu entwickeln, die es erlaubt irreversible thermodynamische Prozesse adequat mittels dieser speziellen Systeme zu modellieren. Dazu wird deren besondere Eigenschaft ausgenutzt, die kanonische Invarianz, d.h. ein kanonisches Ensemble bleibt kanonisch bezüglich hamiltonscher Dynamik. Der Ursprung dieser Invarianz liegt in der dynamischen Algebra, die mit Hilfe der Theorie der Lie-Gruppen näher betrachtet wird. Dies erlaubt, eine weitere besondere Eigenschaft abzuleiten: Die Ensemblemittelwerte unterliegen ebenfalls den Symmetrien, die die dynamische Algebra widerspiegelt. Bei näherer Betrachtung befinden sich alle Trajektorien der Ensemblemittelwerte auf einer Mannigfaltigkeit, die durch den sogenannten Casimir Companion beschrieben wird. Darüber hinaus wird nicht-hamiltonsche/dissipative Dynamik betrachtet, welche zu einer Deformation der Mannigfaltigkeit führt. Abschließend wird eine Zusammenfassung der grundlegenden Methodik zur Modellierung irreversibler Prozesse mittels hamiltonscher Systeme mit dynamischer Algebra gegeben. Zum besseren Verständnis wird ein ausführliches Anwendungsbeispiel dieser Methodik präsentiert, in dem die zeitoptimale Steuerung eines Ensembles des harmonischen Oszillators zwischen zwei Gleichgewichtszuständen sowie zwischen Gleichgewichts- und Nichtgleichgewichtszuständen abgeleitet wird
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Liu, Yukang. "Virtualized Welding Based Learning of Human Welder Behaviors for Intelligent Robotic Welding." UKnowledge, 2014. http://uknowledge.uky.edu/ece_etds/51.
Повний текст джерелаАнотація:
Combining human welder (with intelligence and sensing versatility) and automated welding robots (with precision and consistency) can lead to next generation intelligent welding systems. In this dissertation intelligent welding robots are developed by process modeling / control method and learning the human welder behavior.
Weld penetration and 3D weld pool surface are first accurately controlled for an automated Gas Tungsten Arc Welding (GTAW) machine. Closed-form model predictive control (MPC) algorithm is derived for real-time welding applications. Skilled welder response to 3D weld pool surface by adjusting the welding current is then modeled using Adaptive Neuro-Fuzzy Inference System (ANFIS), and compared to the novice welder. Automated welding experiments confirm the effectiveness of the proposed human response model.
A virtualized welding system is then developed that enables transferring the human knowledge into a welding robot. The learning of human welder movement (i.e., welding speed) is first realized with Virtual Reality (VR) enhancement using iterative K-means based local ANFIS modeling. As a separate effort, the learning is performed without VR enhancement utilizing a fuzzy classifier to rank the data and only preserve the high ranking “correct” response. The trained supervised ANFIS model is transferred to the welding robot and the performance of the controller is examined. A fuzzy weighting based data fusion approach to combine multiple machine and human intelligent models is proposed. The data fusion model can outperform individual machine-based control algorithm and welder intelligence-based models (with and without VR enhancement).
Finally a data-driven approach is proposed to model human welder adjustments in 3D (including welding speed, arc length, and torch orientations). Teleoperated training experiments are conducted in which a human welder tries to adjust the torch movements in 3D based on his observation on the real-time weld pool image feedback. The data is off-line rated by the welder and a welder rating system is synthesized. ANFIS model is then proposed to correlate the 3D weld pool characteristic parameters and welder’s torch movements. A foundation is thus established to rapidly extract human intelligence and transfer such intelligence into welding robots.
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Kesting, Arne. "Microscopic Modeling of Human and Automated Driving: Towards Traffic-Adaptive Cruise Control." Doctoral thesis, Technische Universität Dresden, 2007. https://tud.qucosa.de/id/qucosa%3A24070.
Повний текст джерелаАнотація:
The thesis is composed of two main parts. The first part deals with a microscopic traffic flow theory. Models describing the individual acceleration, deceleration and lane-changing behavior are formulated and the emerging collective traffic dynamics are investigated by means of numerical simulations. The models and simulation tools presented provide the methodical prerequisites for the second part of the thesis in which a novel concept of a traffic-adaptive control strategy for ACC systems is presented. The impact of such systems on the traffic dynamics can solely be investigated and assessed by traffic simulations. The focus is on future adaptive cruise control (ACC) systems and their potential applications in the context of vehicle-based intelligent transportation systems. In order to ensure that ACC systems are implemented in ways that improve rather than degrade traffic conditions, the thesis proposes an extension of ACC systems towards traffic-adaptive cruise control by means of implementing an actively jam-avoiding driving strategy. The newly developed traffic assistance system introduces a driving strategy layer which modifies the driver's individual settings of the ACC driving parameters depending on the local traffic situation. Whilst the conventional operational control layer of an ACC system calculates the response to the input sensor data in terms of accelerations and decelerations on a short time scale, the automated adaptation of the ACC driving parameters happens on a somewhat longer time scale of, typically, minutes. By changing only temporarily the comfortable parameter settings of the ACC system in specific traffic situations, the driving strategy is capable of improving the traffic flow efficiency whilst retaining the comfort for the driver. The traffic-adaptive modifications are specified relative to the driver settings in order to maintain the individual preferences. The proposed system requires an autonomous real-time detection of the five traffic states by each ACC-equipped vehicle. The formulated algorithm is based on the evaluation of the locally available data such as the vehicle's velocity time series and its geo-referenced position (GPS) in conjunction with a digital map. It is assumed that the digital map is complemented by information about stationary bottlenecks as most of the observed traffic flow breakdowns occur at these fixed locations. By means of a heuristic, the algorithm determines which of the five traffic states mentioned above applies best to the actual traffic situation. Optionally, inter-vehicle and infrastructure-to-car communication technologies can be used to further improve the accuracy of determining the respective traffic state by providing non-local information. By means of simulation, we found that the automatic traffic-adaptive driving strategy improves traffic stability and increases the effective road capacity. Depending on the fraction of ACC vehicles, the driving strategy "passing a bottleneck" effects a reduction of the bottleneck strength and therefore delays (or even prevents) the breakdown of traffic flow. Changing to the driving mode "leaving the traffic jam" increases the outflow from congestion resulting in reduced queue lengths in congested traffic and, consequently, a faster recovery to free flow conditions. The current travel time (as most important criterion for road users) and the cumulated travel time (as an indicator of the system performance) are used to evaluate the impact on the quality of service. While traffic congestion in the reference scenario was completely eliminated when simulating a proportion of 25% ACC vehicles, travel times were significantly reduced even with much lower penetration rates. Moreover, the cumulated travel times decreased consistently with the increase in the proportion of ACC vehicles.In der Arbeit wird ein neues verkehrstelematisches Konzept für ein verkehrseffizientes Fahrverhalten entwickelt und als dezentrale Strategie zur Vermeidung und Auflösung von Verkehrsstaus auf Richtungsfahrbahnen vorgestellt. Die operative Umsetzung erfolgt durch ein ACC-System, das um eine, auf Informationen über die lokale Verkehrssituation basierende, automatisierte Fahrstrategie erweitert wird. Die Herausforderung bei einem Eingriff in das individuelle Fahrverhalten besteht - unter Berücksichtigung von Sicherheits-, Akzeptanz- und rechtlichen Aspekten - im Ausgleich der Gegensätze Fahrkomfort und Verkehrseffizienz. Während sich ein komfortables Fahren durch große Abstände bei geringen Fahrzeugbeschleunigungen auszeichnet, erfordert ein verkehrsoptimierendes Verhalten kleinere Abstände und eine schnellere Anpassung an Geschwindigkeitsänderungen der umgebenden Fahrzeuge. Als allgemeiner Lösungsansatz wird eine verkehrsadaptive Fahrstrategie vorgeschlagen, die ein ACC-System mittels Anpassung der das Fahrverhalten charakterisierenden Parameter umsetzt. Die Wahl der Parameter erfolgt in Abhängigkeit von der lokalen Verkehrssituation, die auf der Basis der im Fahrzeug zur Verfügung stehenden Informationen automatisch detektiert wird. Durch die Unterscheidung verschiedener Verkehrssituationen wird ein temporärer Wechsel in ein verkehrseffizientes Fahrregime (zum Beispiel beim Herausfahren aus einem Stau) ermöglicht. Machbarkeit und Wirkungspotenzial der verkehrsadaptiven Fahrstrategie werden im Rahmen eines mikroskopischen Modellierungsansatzes simuliert und hinsichtlich der kollektiven Verkehrsdynamik, insbesondere der Stauentstehung und Stauauflösung, auf mehrspurigen Richtungsfahrbahnen bewertet. Die durchgeführte Modellbildung, insbesondere die Formulierung eines komplexen Modells des menschlichen Fahrverhaltens, ermöglicht eine detaillierte Analyse der im Verkehr relevanten kollektiven Stabilität und einer von der Stabilität abhängigen stochastischen Streckenkapazität. Ein tieferes Verständnis der Stauentstehung und -ausbildung wird durch das allgemeine Konzept der Engstelle erreicht. Dieses findet auch bei der Entwicklung der Strategie für ein stauvermeidendes Fahrverhalten Anwendung. In der Arbeit wird die stauvermeidende und stauauflösende Wirkung eines individuellen, verkehrsadaptiven Fahrverhaltens bereits für geringe Ausstattungsgrade nachgewiesen. Vor dem Hintergrund einer zu erwartenden Verbreitung von ACC-Systemen ergibt sich damit eine vielversprechende Option für die Steigerung der Verkehrsleistung durch ein teilautomatisiertes Fahren. Der entwickelte Ansatz einer verkehrsadaptiven Fahrstrategie ist unabhängig vom ACC-System. Er erweitert dessen Funktionalität im Hinblick auf zukünftige, informationsbasierte Fahrerassistenzsysteme um eine neue fahrstrategische Dimension. Die lokale Interpretation der Verkehrssituation kann neben einer verkehrsadaptiven ACC-Regelung auch der Entwicklung zukünftiger Fahrerinformationssysteme dienen.
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Stoyanova, Petia Venkova. "Knowing and modelling of human enterprises : a holistic approach." Thesis, University of Sunderland, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364526.
Повний текст джерелаАнотація:
The desire to develop a holistic framework for knowing and modelling in human enterprises is not new. Methodologies, such as Systems Dynamics, Soft Systems and the Viable Systems Model all claim a holistic perspective. Each of these approaches emphasises the interrelatedness of `things', rather than the `things' themselves. Thus, they avoid the possible fragmentation that can occur when elements within a situation are treated as if they exist independently. Unfortunately, the systems approaches flounder because they fail to reconcile knowledge with the path that brings it into being, or to satisfactorily deal with the concepts of order or communication in language. The Thesis, therefore, provides a greater clarification of these issues, in the light of enactive cognitive science, chaos theory and contemporary theories on dialogue. As a result, a new framework is presented, for knowing and modelling in human enterprises, that is based on our `new' understanding of holism. The organisational context of the Thesis is provided by two generic models, both developed by the author (a model of Duopoly Competition and a model of Chaos Control ), together with a case study of the Danish hearing aid manufacturer Oticon. The Thesis concludes by presenting various insights arising from our new frame of reference and reflecting on their challenges for organisations.
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Schröder, Jochen. "Modelling, state observation and diagnosis of quantised systems /." Berlin [u.a.] : Springer, 2003. http://www.loc.gov/catdir/enhancements/fy0813/2002030222-d.html.
Повний текст джерела
50
Myklebust, Odd. "Enterprise Modelling supported by Manufacturing Systems Theory." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Engineering Science and Technology, 2002. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-83.
Повний текст джерелаАнотація:
There exist today a large number of enterprise models or enterprise modelling approaches. In a study of standards and project developed models there are two approaches: CIMOSA “The Open Systems Architecture for CIM” and GERAM, “Generalised Enterprise Reference Architecture”, which show a system orientation that can be further followed as interesting research topics for a system theory oriented approach for enterprise models.
In the selection of system theories, manufacturing system theory is interesting and promising to adapt or extend to further synthesising and usage of enterprise models.
Today the design and creation of an enterprise model are based on a given architecture and available even though this is not always practical. When it comes to execution and operational phases of the model, the possibilities are more limited.
Manufacturing system theory [Bjørke 1995] was developed to describe system-oriented approaches to manufacturing systems including product configuration and design processes. This includes a large number of disciplines like mechanics, cybernetics, material science etc. on the physical side and planning activities, economical aspects and optimisation processes on the human side. The theory is based on geometry as the foundation and the methods within the theory are related to concepts of connections. The analysis of the manufacturing systems is the prime area for the usage of this theory and is important in order to bring a science base into manufacturing. But the theory can be used in a more generic way.
The theory of logic [Møller 1995] relates also to the concept of connections, being expressed as logic arguments. The theory is generic and has been applied to different model approaches e.g. product configuration, scheduling and planning, railway logic control. This theory of logic is also fully applicable in manufacturing system theory. The theory of logic and the manufacturing systems theory are both based on geometry or more precisely expressed the geometric funded theory of connections.
The main requirement for the enterprise model architecture to be used together with the theory of logic is that it can be divided into a 3D orthogonal space with unique defined axis. In this work a 3D space based upon product, process and organisational axis is preferred, also called the PPO-model. In this study combination of the enterprise modelling architecture, GERAM ISO 15704, and the theory of logic are used to show how systems theory can be used in control and management of operational phases of enterprise models. The usage of logic theory within enterprise modelling gives solutions on management and control issues in an operational phase of the product model. If is important to emphasis that this is not an approach for populating or transfer of operative data into a model. The integration of theses theories are illustrated through examples that show modelled entities of an enterprise in operation within areas of:
- Execution of operative manufacturing unit
- Organisational and strategic issues
- Enterprise planning with aspects of uncertainty
An own PPO model for feature based integration within product design and process planning has been developed to show that alternative more simple and detailed architectures also can be used.