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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.
181

TPM orients enterprises towards production excellence : A Practical Analysis of OEE

Zhu, Jiajia, Liu, Yong January 2009 (has links)
Purpose – The purpose of this paper is to review the literatures on Total Productive Maintenance (TPM) and to present an overview of TPM implementation practices initiated in a ‘connecter’ manufacturer in China. It also examines the need to develop, practice and implement such maintenance campaign, which not only reduce unscheduled and scheduled failures in process but also decrease operation and maintenance costs. Design/methodology/approach – A case-based approach in combination with scientific theory and standard tools, techniques and practices is used to discuss various issues related with TPM implementation in industry. Findings – The findings indicate that TPM not only leads to increase in efficiency and effectiveness of manufacturing equipments measured in terms of OEE index by reducing the failure, time loss, and defects but also helps organization to improve morale of people and working environment significantly. The contributions of strategic TPM programs towards improving manufacturing competencies of the organizations have also been highlighted here. Originality/value – The paper contains a comprehensive literature on the field of equipment maintenance and also presents an interesting investigation of TPM implementation issues which may be useful to researchers, maintenance professionals and other practitioners concerned with maintenance to understand the significance of TPM.
182

Optimizing Enzymatic Preparations of Mechanical Pulp Through the Characterization of New Laccases and Non-productive Interactions Between Enzymes and Lignin

Waung, Debbie 30 December 2010 (has links)
The overall objective of this research is to identify and optimize enzymatic applications that have the potential to degrade middle lamella lignin, so as to decrease economic and environmental costs associated with the production of mechanical pulp. Non-productive binding of enzyme to lignin in lignocellulosic biomass reduces enzyme availability and efficiency. The elucidation of non-productive binding behavior between hydrolytic enzymes and lignocellulosic substrates could significantly improve the efficiency of corresponding industrial bioprocesses. The first part of this report presents a study that characterizes non-catalytic interactions between enzymes and fibre. The second part of this report presents the biochemical and mutational studies of a novel, small laccase SCO6712 from Streptomyces coelicolor. The findings from this research support the design, control, and optimization of enzymatic treatments of lignocellulosic fibres in the pulp and biofuel industries.
183

Optimizing Enzymatic Preparations of Mechanical Pulp Through the Characterization of New Laccases and Non-productive Interactions Between Enzymes and Lignin

Waung, Debbie 30 December 2010 (has links)
The overall objective of this research is to identify and optimize enzymatic applications that have the potential to degrade middle lamella lignin, so as to decrease economic and environmental costs associated with the production of mechanical pulp. Non-productive binding of enzyme to lignin in lignocellulosic biomass reduces enzyme availability and efficiency. The elucidation of non-productive binding behavior between hydrolytic enzymes and lignocellulosic substrates could significantly improve the efficiency of corresponding industrial bioprocesses. The first part of this report presents a study that characterizes non-catalytic interactions between enzymes and fibre. The second part of this report presents the biochemical and mutational studies of a novel, small laccase SCO6712 from Streptomyces coelicolor. The findings from this research support the design, control, and optimization of enzymatic treatments of lignocellulosic fibres in the pulp and biofuel industries.
184

A Community of Smarks: Professional Wrestling and the Changing Relationship between Textual Producers and Consumers

Toepfer, Shane 03 August 2006 (has links)
This analysis of the professional wrestling genre attempts to understand the complex reading practices employed by wrestling’s fan community. I argue that wrestling fans consume these texts in the context of both the official narratives of media producers and the meta-narratives that exist independently of the official texts. In addition, I argue that wrestling fans display characteristics normally reserved for traditional media producers, collaborating with those producers over the direction of the official narratives. This process of collaboration is indicative of the blurring of the boundaries between textual producers and consumers and necessitates a theoretical conception of the audience that accounts for these unique fan practices. I have called this audience conception the productive audience model.
185

Measuring For Improvement: A study of production processes’ effectiveness and the potential for improvements at Nobel Biocare

Ben Or, Yaniv January 2010 (has links)
Purpose: this thesis study aims to provide an analysis and an assessment of the current operations’ performance effectiveness at Nobel Biocare’s production plant in Karlskoga, Sweden and to describe the potential for improvement. It intends to clarify the importance of performance measurement and explain Overall Equipment Effectiveness (OEE) metrics in particular.Furthermore, it strives to identify causes for inefficiency in production and suggest recommendations to minimize losses. Methodology: the study is using both qualitative and quantitative approaches in parallel as measurements are implemented to discover effectiveness rates and detect causes for production losses while assessments are made using different models, such as the Capability Maturity Model(CMM) and OEE assessments, in order to evaluate the current development level and the potential for improvement. Findings: the research finds that major losses are closely related to frequency of changeovers in machining processes, where average effectiveness rates were 68%. In surface treatment and packaging equipment inspected, the values were found to be between 46% and 59% as the major common cause was the absence of work due to unstable flow of orders. Assessing process orientation and maturity levels, the findings indicate on high levels in general. However, areas of weakness were identified in the different processes in which the potential for improvement is embedded. In those areas, lower OEE values were registered; low levels of maturity and process orientation were found, as low development of losses improvement were assessed. The study finally suggests that the areas of weakness suffer from lack of learning orientation that is ought to be improved and at the same time, a variety of specific recommendations are provided.
186

Measuring For Improvement: A study of production processes’ effectiveness and the potential for improvements at Nobel Biocare

Ben Or, Yaniv January 2010 (has links)
Purpose:this thesis study aims to provide an analysis and an assessment of the current operations’ performance effectiveness at Nobel Biocare’s production plant in Karlskoga, Sweden and to describe the potential for improvement. It intends to clarify the importance of performance measurement and explain Overall Equipment Effectiveness (OEE) metrics in particular. Furthermore, it strives to identify causes for inefficiency in production and suggest recommendations to minimize losses. Methodology: the study is using both qualitative and quantitative approaches in parallel as measurements are implemented to discover effectiveness rates and detect causes for production losses while assessments are made using different models, such as the Capability Maturity Model(CMM) and OEE assessments, in order to evaluate the current development level and the potential for improvement. Findings: the research finds that major losses are closely related to frequency of changeovers in machining processes, where average effectiveness rates were 68%. In surface treatment and packaging equipment inspected, the values were found to be between 46% and 59% as the major common cause was the absence of work due to unstable flow of orders. Assessing process orientation and maturity levels, the findings indicate on high levels in general. However, areas of weakness were identified in the different processes in which the potential for improvement is embedded. In those areas, lower OEE values were registered; low levels of maturity and process orientation were found, as low development of losses improvement were assessed. The study finally suggests that the areas of weakness suffer from lack of learning orientation that is ought to be improved and at the same time, a variety of specific recommendations are provided.
187

Utvärdering och Implementering av underhållssystem : Evulation and implementation of a Maintenace Management System

Svensson, Ulrika January 2006 (has links)
Detta examensarbete beskriver hur förarbetet till att datorisera ett underhållssystem genomförs. Uppdragsgivare är Lear Corporation i Torslanda. Examensarbetet består av två delar: utvärdera en på förhand vald programvara och att dokumentera allt förebyggande underhåll (FU). Syftet är att få bättre kontroll och planering av förebyggande underhåll (FU) i framtiden. Programvaran som skall utvärderas om den är lämplig för ändamålet heter Tekla™ Maintenance. Målet var att dokumentera allt förebyggande underhåll (FU) för två av tre liner i Lear Corporations fabrik i Torslanda. Det visade sig att Tekla™ Maintenance uppfyllde de krav som fanns. De krav som fanns var bland annat när det var dags att göra ett förebyggande underhållsarbete ska programmet automatiskt tala om att nu skall det utföras. Ett användarvänligt gränssnitt var också efterfrågat. Rapporten innerhåller även en beskrivning av hur Tekla™ Maintenance är uppbyggt. För att få en bild av hur det är att arbeta med programmet i verkligheten genomfördes en benchmarking mot Plastal AB. Plastal AB hade mycket goda erfarenheter av att arbeta med programmet och kunde därför varmt rekommendera det. All dokumentation av förebyggande underhåll sker i dag på papper. Eftersom denna dokumentation inte innehöll tillräckligt med information skedde nedbrytningen från grunden. Varje line delades in i mindre områden så som line, kringutrustning och moment- och skruvdragare. När allt var dokumenterat fick underhållspersonalen tala om vad för slags förebyggande underhåll som skulle göras på all utrustning. Allt skrevs in i en Excel-fil som skall användas för att importera informationen till Tekla™ Maintenance i framtiden. Filen innerhåller över 2000 stycken objekt, vilket ger en bra grund för underhållsarbetet i framtiden. / This Bachelor Thesis deals with how to prepare a computerization of a Maintenance Management System. The Bachelor Thesis is written by commission at Lear Corporation in Torslanda, Sweden. The paper is divided into two parts: evaluate a software and document all preventive maintenance. The purpose is to get better control and planning of preventive maintenance in the future. Tekla™ Maintenance is the software that is going to be evaluated. The aim is to document all preventive maintenance for two of three production lines at Lear Corporations factory at Torslanda, Sweden. The research shows that Tekla™ Maintenance met the specifications. One of the basic requirements was to automate the management of prevention maintenance activity, by issuing work order. Furthermore a user friendly interface was required. A description of Tekla™ Maintenance is included in the report. To get a feeling of how the programme perform in real world, benchmarking was preformed against Plastal AB. The benchmarking resulted in that Plastal AB recommended the Tekla™ Maintenance programme. Currently the documentation does not contain enough detailed information to allow a thorough review of all production lines. By dividing all lines into zones, all activities at each zone have been documented. Feedback form the operators was given, about what type of preventive maintenance that is required. To be able to put all the information into Tekla™ Maintenance, an Excel file has been made. This file contains over 2000 entries and should provide a solid base for future preventive maintenance.
188

The Study of Dynamic Agglomeration Externalities in Taiwan Manufacturing Industries:An Application for Dynamic Network DEA

Ho, Po-cheng 21 July 2010 (has links)
Any one organization or agency, whether for-profit or non-profit organizations that are seeking to enhance their efficiency, improve production technology, thereby achieving the goal of improving productivity, with a view to the current competitive environment. Efficiency measurement is very important, it can help decision makers understand whether the organization achieve technology progress and innovation objectives. In recent years, the government and civil organizations devote themselves to measure the change of organizational efficiency and productivity. Academia constantly research and develop various models of efficiency and productivity analysis, and application to actual cases analysis. Efficiency and productivity analysis has leapt to the mainstream of production economic studies. This empirical study adopts the census data of the classification of the Chamber of Commerce and industry of manufacturing in Taiwan, using two-stage approach to explore dynamic agglomeration externalities of 2-digit manufacturing. In the first stage, we apply dynamic network data envelopment analysis and Malmquist productivity index to calculate static efficiency and dynamic efficiency of 2-digit manufacturing. In the second stage, we apply Tobit regression analysis to verify a manufacturing geographical concentration effects on productive efficiency. We also adopt two-stage least squares methods (2SLS) to validate dynamic agglomeration externalities effects of manufacturing. Based on the results of this empical study, we propose some specific practical policy alternatives and management strategies. In the last 20 years, the strctures of Taiwan manufacturing industries have significant changes, the livelihood industry and of the sharp decline in industry, the chemical industry, electronics industry, metal machinery industry is growing fast. There is an obvous agglomeration tendency toward northern Taiwan region. In static efficiency, labour-intensive manufacturing industries tend to be diminishing return to scale rendering, while knowledge-intensive industries are rendering the increasing trend. The scale efficiency of eastern region manufacturing is very low, resulting in their productive efficiency significantly lower than the northern, central, southern regional manufacturing. In dynamic efficiency, the total factor productivity (TFP) of Taiwan manufacturing industries are rendering the growth trend, achieving the goal of innovation effect. However, the technical efficiency of manufacturing are rendering decline trend. This study found that the most important impact factor on production efficiency is the internal economies of scale. Localization economies, urbanization economies, and other static agglomeration economies external effect gradually reduce. Moreover, this study also found that Taiwan manufacturing industries have notable MAR professional dynamic external economics and notable Porter regional competitive dynamic external economic effect. Besides, Taiwan manufacturing industries has noticeable human resource dynamic external economics, but we also found low wages is beneficial to regional economic growth. We should not expand to explain Taiwan manufacturing-sweatshops. This phenomenon may be caused by high salaries, high rents, high land costs and high labor costs, these factors offset the interest of agglomeration economies. Finally, Taiwan and mainland China signed a cross-strait economic cooperation framework agreement (ECFA) in Chongqing on 29 June 2010. Taiwan manufacturing inevitably be impacted and influenced by ECFA. This is an important topic worthy of further study and discussion in the future.
189

Utvärdering och Implementering av underhållssystem : Evulation and implementation of a Maintenace Management System

Svensson, Ulrika January 2006 (has links)
<p>Detta examensarbete beskriver hur förarbetet till att datorisera ett underhållssystem genomförs. Uppdragsgivare är Lear Corporation i Torslanda. Examensarbetet består av två delar: utvärdera en på förhand vald programvara och att dokumentera allt förebyggande underhåll (FU). Syftet är att få bättre kontroll och planering av förebyggande underhåll (FU) i framtiden. Programvaran som skall utvärderas om den är lämplig för ändamålet heter Tekla™ Maintenance.</p><p>Målet var att dokumentera allt förebyggande underhåll (FU) för två av tre liner i Lear Corporations fabrik i Torslanda.</p><p>Det visade sig att Tekla™ Maintenance uppfyllde de krav som fanns. De krav som fanns var bland annat när det var dags att göra ett förebyggande underhållsarbete ska programmet automatiskt tala om att nu skall det utföras. Ett användarvänligt gränssnitt var också efterfrågat. Rapporten innerhåller även en beskrivning av hur Tekla™ Maintenance är uppbyggt.</p><p>För att få en bild av hur det är att arbeta med programmet i verkligheten genomfördes en benchmarking mot Plastal AB. Plastal AB hade mycket goda erfarenheter av att arbeta med programmet och kunde därför varmt rekommendera det.</p><p>All dokumentation av förebyggande underhåll sker i dag på papper. Eftersom denna dokumentation inte innehöll tillräckligt med information skedde nedbrytningen från grunden. Varje line delades in i mindre områden så som line, kringutrustning och moment- och skruvdragare. När allt var dokumenterat fick underhållspersonalen tala om vad för slags förebyggande underhåll som skulle göras på all utrustning. Allt skrevs in i en Excel-fil som skall användas för att importera informationen till Tekla™ Maintenance i framtiden. Filen innerhåller över 2000 stycken objekt, vilket ger en bra grund för underhållsarbetet i framtiden.</p> / <p>This Bachelor Thesis deals with how to prepare a computerization of a Maintenance Management System. The Bachelor Thesis is written by commission at Lear Corporation in Torslanda, Sweden. The paper is divided into two parts: evaluate a software and document all preventive maintenance. The purpose is to get better control and planning of preventive maintenance in the future. Tekla™ Maintenance is the software that is going to be evaluated.</p><p>The aim is to document all preventive maintenance for two of three production lines at Lear Corporations factory at Torslanda, Sweden.</p><p>The research shows that Tekla™ Maintenance met the specifications. One of the basic requirements was to automate the management of prevention maintenance activity, by issuing work order. Furthermore a user friendly interface was required. A description of Tekla™ Maintenance is included in the report.</p><p>To get a feeling of how the programme perform in real world, benchmarking was preformed against Plastal AB. The benchmarking resulted in that Plastal AB recommended the Tekla™ Maintenance programme.</p><p>Currently the documentation does not contain enough detailed information to allow a thorough review of all production lines.</p><p>By dividing all lines into zones, all activities at each zone have been documented.</p><p>Feedback form the operators was given, about what type of preventive maintenance that is required.</p><p>To be able to put all the information into Tekla™ Maintenance, an Excel file has been made. This file contains over 2000 entries and should provide a solid base for future preventive maintenance.</p>
190

The role of productive struggle in teaching and learning middle school mathematics

Warshauer, Hiroko Kawaguchi 03 February 2012 (has links)
Students’ struggle with learning mathematics is often cast in a negative light. Mathematics educators and researchers, however, suggest that struggling to make sense of mathematics is a necessary component of learning mathematics with understanding. In order to investigate the possible connection between struggle and learning, this study examined students’ productive struggle as students worked on tasks of higher cognitive demand in middle school mathematics classrooms. Students’ productive struggle refers to students’ “effort to make sense of mathematics, to figure something out that is not immediately apparent” (Hiebert & Grouws, 2007, p. 287) as opposed to students’ effort made in despair or frustration. As an exploratory case study using embedded multiple cases, the study examined 186 episodes of student‐teacher interactions in order to identify the kinds and nature of student struggles that occurred in a naturalistic classroom setting as students engaged in mathematical tasks focused on proportional reasoning. The study identified the kinds of teacher responses used in the interaction with the students and the types of resolutions that occurred. The participants were 327 6th and 7th grade students and their six mathematics teachers from three middle schools located in mid‐size Texas cities. Findings from the study identified four basic types of student struggles: get started, carry out a process, give a mathematical explanation, and express misconception and errors. Four kinds of teacher responses to these struggles were identified as situated along a continuum: telling, directed guidance, probing guidance, and affordance. The outcomes of the student‐teacher interactions that resolved the students’ struggles were categorized as: productive, productive at a lower level, or unproductive. These categories were based on how the interactions maintained the cognitive level of the implemented task, addressed the externalized student struggle, and built on student thinking. Findings provide evidence that there are aspects of student‐teacher interactions that appear to be productive for student learning of mathematics. The struggle‐response framework developed in the study can be used to further examine the phenomenon of student struggle from initiation, interaction, to its resolution, and measure learning outcomes of students who experience struggle to make sense of mathematics. / text

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