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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

El traductor e intérprete emprendedor: análisis de la supervivencia de las empresas y los empresarios autónomos

Gieure Sastre, Clara 12 April 2016 (has links)
This study presents an empirical analysis of the determinants of firm and self-employed survival in the Spanish translation sector. In the midst of a global downturn firm and self-employed survival is a key factor for the progress of the economies and for a better and more stable future. The study presents, first of all, a review of the literature on translation, interpreting, career opportunities, and entrepreneurship, and firm survival. The following empirical analysis explores the combination of variables of human capital, contingency and economic investment that potentially drive translation and interpreting firms or self-employed entrepreneurs to survive. The study performs a comparative qualitative analysis with a fs/QCA methodology identifying nine combination of causes that lead to the outcome. The results contribute towards a better understanding of entrepreneur translators’ lifespan as they provide an empirical outlook on the different causal paths that predict the survival of those translation and interpreting firms or self-employed entrepreneurs. The last part concludes with the most relevant findings of this research study. With little literature on the topic of firm survival in the translation and interpreting sector the paper aims to fill this gap and make a valuable contribution to the current literature on translation-firm creation and firm and self-employed survival.
32

Optimization of industrial shop scheduling using simulation and fuzzy logic

Rokni, Sima 06 1900 (has links)
The percentage of shop fabrication, including pipe spool fabrication, has been increasing on industrial construction projects during the past years. Industrial fabrication has a great impact on construction projects due to the fact that the productivity is higher in a controlled environment than in the field, and therefore time and cost of construction projects are reduced by making use of industrial fabrication. Effective planning and scheduling of the industrial fabrication processes is important for the success of construction projects. This thesis focuses on developing a new framework for optimizing shop scheduling, particularly pipe spool fabrication shop scheduling. The proposed framework makes it possible to capture uncertainty of the pipe spool fabrication shop while accounting for linguistic vagueness of the decision makers preferences using simulation modeling and fuzzy set theory. The implementation of the proposed framework is discussed using a real case study of a pipe spool fabrication shop. In this thesis, first, a simulation based scheduling framework is presented based on the integration of relational database management system, product modeling, process modeling, and heuristic approaches. Next, a framework for optimization of the industrial shop scheduling with respect to multiple criteria is proposed. Fuzzy set theory is used to linguistically assess different levels of satisfaction for the selected criteria. Additionally, an executable scheduling toolkit is introduced as a decision support system for pipe spool fabrication shop. / Construction Engineering and Management
33

Uncertainty Modeling Health Risk Assessment and Groundwater Resources Management

Kentel, Elçin 10 July 2006 (has links)
Real-world problems especially the ones that involve natural systems are complex and they are composed of many non-deterministic components. Uncertainties associated with these non-deterministic components may originate from randomness or from imprecision due to lack of information. Until recently, uncertainty, regardless of its nature or source has been treated by probability concepts. However, uncertainties associated with real-world systems are not limited to randomness. Imprecise, vague or incomplete information may better be represented by other mathematical tools, such as fuzzy set theory, possibility theory, belief functions, etc. New approaches which allow utilization of probability theory in combination with these new mathematical tools found applications in various engineering fields. Uncertainty modeling in human health risk assessment and groundwater resources management areas are investigated in this thesis. In the first part of this thesis two new approaches which utilize both probability theory and fuzzy set theory concepts to treat parameter uncertainties in carcinogenic risk assessment are proposed. As a result of these approaches fuzzy health risks are generated. For the fuzzy risk to be useful for practical purposes its acceptability with respect to compliance guideline has to be evaluated. A new fuzzy measure, the risk tolerance measure, is proposed for this purpose. The risk tolerance measure is a weighed average of the possibility and the necessity measures which are currently used for decision making purposes. In the second part of this thesis two decision making frameworks are proposed to determine the best groundwater resources management strategy in the Savannah region, Georgia. Groundwater resources management problems, especially ones in the coastal areas are complex and require treatment of various uncertain inputs. The first decision making framework proposed in this study is composed of a coupled simulation-optimization model followed by a fuzzy multi-objective decision making approach while the second framework includes a groundwater flow model in which the parameters of the flow equation are characterized by fuzzy numbers and a decision making approach which utilizes the risk tolerance measure proposed in the first part of this thesis.
34

A Study on Fuzzy Temporal Data Mining

Lin, Shih-Bin 06 September 2011 (has links)
Data mining is an important process of extracting desirable knowledge from existing databases for specific purposes. Nearly all transactions in real-world databases involve items bought, quantities of the items, and the time periods in which they appear. In the past, temporal quantitative mining was proposed to find temporal quantitative rules from a temporal quantitative database. However, the quantitative values of items are not suitable to human reasoning. To deal with this, the fuzzy set theory was applied to the temporal quantitative mining because of its simplicity and similarity to human reasoning. In this thesis, we thus handle the problem of mining fuzzy temporal association rules from a publication database, and propose three algorithms to achieve it. The three algorithms handle different lifespan definitions, respectively. In the first algorithm, the lifespan of an item is evaluated from the time of the first transaction with the item to the end time of the whole database. In the second algorithm, an additional publication table, which includes the publication date of each item in stores, is given, and thus the lifespan of an item is measured by its entire publication period. Finally in the third algorithm, the lifespan of an item is calculated from the end time of the whole database to its earliest time in the database for the item to be a fuzzy temporal frequent item within the duration. In addition, an effective itemset table structure is designed to store and get information about itemsets and can thus speed up the execution efficiency of the mining process. At last, experimental results on two simulation datasets compare the mined fuzzy temporal quantitative itemsets and rules with and without consideration of lifespans of items under different parameter settings.
35

The Application of Fuzzy Set Theory for Cage Aquaculture Site Selection

Ma, Guo-Ding 14 July 2000 (has links)
The research focuses on the application of site selection for cage aquaculture in Taiwan by developing the site evaluation DSS (Decision Support System). The modeling aspect of the system belongs to the domain of multi-criteria decision theories, which AHP (Analytic Hierarchy Process) and Fuzzy Set theory were used. Two case studies based on real world and hypothetical data were conducted to verify the integrity of the system. According to the literature review and the interview with several domain experts, various impact factors were identified first. The corresponding weights of each factor were then decided by analyzing the questionnaires designed based on the concept of AHP. The following work was to evaluate those impact factors based on the experience of domain experts using some appropriate approaches. To represent the domain knowledge, it is appropriate to use rule based inference system. Besides, fuzzy set theory was chosen to describe the antecedent and consequence of the rule base due to the considerations of uncertainty from human experts and ocean field data. Several related mythologies derived from the fuzzy set theory were used, such as the operation of fuzzy composition, determination of suitable membership function, fuzzy relationship matrix, fuzzy inference, defuzzification, and fuzzy pattern classification. All impact factors were categorized into three different types of membership functions that were designed specifically for the site selection of cage aquaculture. The consequence in the rule base, which is the site suitability, was also represented as the unique membership function. To calculate the fuzzy relationship matrix, the current research found that the operation of ¡§algebraic product and bounder sum¡¨ would produce better results than the commonly used ¡§max-min¡¨ operation. Each impact factor would have the associated fuzzy relationship matrix derived from the rule base. The site suitability in term of a fuzzy set can then be inferred by the fuzzy composition of current situation of the factor and the relationship matrix. By multiplying the AHP weight and the fuzzy suitability, the final site suitability index, taking all the impact factors into consideration, can therefore be derived. The real data in Feng-Gang, located in the southern Taiwan, were collected and evaluated using the site selection DSS. The results show Feng-Gang is suitable for the development of cage aquaculture, which is validated by the current prosperous business locally in cage aquaculture. As for the evaluation of multiple sites, 18 hypothetical sites near shore around Taiwan were chosen to calculate the corresponding suitability indexes, which were then be partitioned into several groups using the fuzzy pattern classification. Based on the results, the sites that were classified in the same group have similar cultivation conditions, which also proves the applicability of the site evaluation DSS.
36

Takagi-Sugeno and Mamdani Fuzzy Control of a Resort Management System

Tan, Lujiao January 2012 (has links)
By means of fuzzy set theory as well as Takagi-Sugeno and Mamdani fuzzy controller, this paper presents the investigation of a Resort Management System implemented by a combination of a T-S model and a Mamdani model. It demonstrates the procedure of the specific premise parameters identification and consequence parameters identification performed by regression knowledge in the T-S model, and the process of the fuzzification, the rule base creation and the defuzzification with COG technique in the Mamdani model. Therefore, an aggregation between T-S controller and Mamdani controller applied in the field of management by a novel angle is illustrated, which, as a result, devotes an improved management system that shares great convenience in the control process when combined with mathematics. Moreover, a modification of the conventional Takagi-Sugeno and Mamdani controller is demonstrated in conjunction with fuzzy operations t-norms and OWA by adjusting the -value, which is used in the calculation of final outputs in the T-S model and the computation of rule consequences in the Mamdani model. The algebraic intersection, bounded intersection as well as the -parameter t-norm are the t-norms which are going to be introduced. Besides, we have tested that t-norms generate the same alpha values when the membership degrees meet the boundary with the value of 1 or 0 while OWA can still yield a well-balanced result different from the one computing by minimum operation. Nevertheless both t-norms and OWA are able to shift the alpha-value in a well-adjusted way when the membership degrees lie in the interval [0,1]. A tendency has been shown that alpha-value tends to decrease by means of t-norms and OWA operations and consequently, the final outputs appear to be reduced.
37

Automated Pattern Recognition for Intonation (PRInt) : an essay on intonational phonology and categorization / Essay on intonational phonology and categorization

Bacuez, Nicholas 25 February 2013 (has links)
This dissertation provides experimental evidence for the validity of an intonational phonology. The widely used Autosegmental-Metrical theory con- tends that the phonological structure of intonation can be expressed with two tonal targets (L/H tones and derivatives) and retrieved from its phonetic im- plementations. However, it has not been specifically demonstrated so far in a systematic way. This dissertation argues that this view on intonational phonol- ogy considers the phonetic forms of intonation as instances of phonologically structured intonational units forming functionally discrete categories (tones and derivatives). The model of Pattern Recognition for Intonation (PRInt) applies the concepts of categorization (vagueness, prototype, degrees of typicality) to in- tonation in order to abstract the phonological structure of intonational cate- gories from the ranking, by degree of typicality, of their variations in phonetic implementation. First, instances belonging to an intonation category are collected. Sec- ond, a pattern recognition module, relying on the 4-layer structure protocol, extracts a feature vector from the phonetic data of each instance: a sequence of structurally organized tones (L/H tones and derivatives). Third, a fuzzy classifier, using two functions (frequency and similar- ity), organizes the data from the feature vectors of all instances by degree of typicality (grade of membership of values in multisets) and generates the phonological structure of the intonation category, the prototypical pattern, ex- tracted from all instances, and that subsumes them all. It also re-creates the phonetic implementations of the phonological structure but with their features ranked by degree of typicality. This allows the model to distinguish phono- logically distinct structures from phonetic variations of the same phonological structure. The model successfully extracted the phonological intonation structure associated to three modalities of closed questions in French: neutral, doubt- ful, and surprised. It found that neutral and doubtful closed questions are phonologically distinct while surprise is a phonetic allocontour of the neutral modality, in line with prior characterizations of these patterns. It demon- strated that a bi-tonal phonological structure of intonation can be retrieved from phonetic variations. A versatile modeling tool, PRInt will be developed to use its acquired knowledge to evaluate the categorical status of novel instances and to extract multiple phonological units from mixed corpora. / text
38

Optimization of industrial shop scheduling using simulation and fuzzy logic

Rokni, Sima Unknown Date
No description available.
39

A Conflictive Triuvirate Consruct of Epidemiologic Systems Failure

Ulinwa, Ngozi Lois 01 January 2019 (has links)
Epidemiologic systems failure (ESF) is a major hurdle in minimizing the spread of infectious diseases during outbreaks. The reasons for ESF include the technical limitation of personnel handling epidemic crises, strictly defined health policies that limit the actions of epidemiologists, and personal perspective's reservations towards the intentions of health agencies. The purpose of this triumvirate mixed-methods case study was to examine factors of infectious disease control mechanisms useful for determining ESF. Three juxtaposed pre-emptive factors (technical [T], organizational [O], and personal [P] perspectives were used to determine how the multiple perspectives inquiring systems and fuzzy logic revealed factors causing ESF so that remedial tools may be constructed. The juxtaposed ESF-TOP model formed the research theoretical framework and allowed for clustering the ESF factors. Data sources were direct quotations from TOP based secondary data of 4 well-publicized participants; who had Ebola, HIV-AIDS, Tuberculosis, or Typhoid disease; and randomized quantitative TOP hypothetical data sets were created with Microsoft Excel software and used to model an Ebola outbreak of 10 theoretical subjects. Data were analyzed using TOP guidelines from which T, O, and P perspective themes emerged. The findings indicated that a disjointed TOP perspective specifies a serious ESF, a strictly overlapped TOP indicates an effective containment of ESF, and the overall fuzzy set with T given O and P indicates the actual ESF. The findings may result in positive social change by helping epidemiologists identify critical outbreak control factors which may minimize the outbreak impact.
40

Vývojové prostředí pro umělou inteligenci Modul fuzzy čísel / Integrated development environment for Artificial Intelligence Fuzzy Numbers Module

Pergl, Miroslav January 2009 (has links)
Master’s thesis deals with mathematical operation with fuzzy numbers. The first part of the thesis deals with theoretical knowledge of fuzzy arithmetic and defines fuzzy sets, fuzzy numbers, universum and five membership function used in program. In the concrete it describes – cut method for dealing with fuzzy numbers as with limited interval for specific level which simplifies computation. The second part of the thesis contains description of programmed module for mathematical operation with fuzzy numbers. There is described creation of user interface which is using to set parameters of computation. There are also described support functions which make operation with fuzzy numbers possible and operation ensures output.

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