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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.
11

Analýza způsobů zvyšování efektivnosti ve veřejném sektoru s využitím příkladu příspěvkové organizace Česká geologická služba. / Analysis of ways improving efficiency in the public sector by using example of a semi-budgetary organization Czech Geological Survey.

Horáková, Lucie January 2014 (has links)
This paper is focused on evaluation and improvement of the allocative efficiency of the public sector. The introductory chapters give us information about the necessity of existence, operation and financing of the public sector and its representation in public finances. Rules for establishing, financing and management of semi-budgetary organizations are discused in a more elaborated manner. The theoretical part explains the concept of efficiency and provides a detailed overview of methods of measuring the efficiency in the public sector by various authors. In the practical part, the theoretical approaches are demonstrated on the example of the Czech Geological Survey (ČGS). ČGS is a semi- budgetary organization established by the Ministry of the Environment, but partly also works as a research organization. Also there are given the competences and organizer's requirements. Financing of the organization is provided from several sources, whereas the contribution from the organizers part is reduced on a year to year basis and the organization is forced to cover the loss by research activities and providing services to foreign customers. The effectiveness analysis is based on the concept of Sintonen. However it is complicated by the fact that ČGS is on one hand A semi-budgetary organization and on the other A research organization. For the semi-budgetary organizationS the appropriate approach is to minimize costs, but for the research organization it is rather about increasing revenues. For the highest efficiency possible it is necessary to find a combination of both approaches.
12

Measurement of Power Losses of Rolling Element Bearings under Tightly ControlledTemperature and Loading Conditions

Garg, Ayush January 2020 (has links)
No description available.
13

Development of a Comprehensive Framework for the Efficiency Measurement of Road Maintenance Strategies using Data Envelopment Analysis

Ozbek, Mehmet Egemen 12 October 2007 (has links)
For the last two decades, the road maintenance concept has been gaining tremendous attention. This has brought about new institutional changes, predominant of which is the challenge for maintenance managers to achieve maximum performance from the existing road system. Such challenge makes it imperative to implement comprehensive systems that measure road maintenance performance. However, the road maintenance performance measurement systems developed and implemented by researchers and state departments of transportation (DOTs) mainly focus on the effectiveness measures, e.g., the level-of-service. Such measurement systems do not sufficiently elaborate on the efficiency concept, e.g., the amount of resources utilized to achieve such level-of-service. Not knowing how "efficient" state DOTs are in being "effective" can lead to excessive and unrealistic maintenance budget expectations. This issue indicates the need for a performance measurement approach that can take the efficiency concept into account. Another important concept that is not investigated in the current road maintenance performance measurement systems is the effect of the environmental factors (e.g., climate, location, and etc.) and operational factors (e.g., traffic, load, design-construction adequacy, and etc.) on the performance of the road maintenance process. This issue, again, indicates the need for a performance measurement approach that can take such external and uncontrollable factors into account. The purpose of this research is to develop and implement a comprehensive framework that can measure the relative efficiency of different road maintenance strategies given the (i) multiple inputs and outputs that characterize the road maintenance process and (ii) uncontrollable factors (e.g., climate, traffic, etc.) that affect the performance of such process. It is challenging to measure the overall efficiency of a process when such process is a multiple input-multiple output process and when such process is affected by multiple factors. To address this challenge, an innovative approach to efficiency measurement, Data Envelopment Analysis, is used in this research. It is believed that this research, by taking the efficiency concept into account, will significantly improve the ways that are currently used to model and measure the performance of road maintenance. The findings of this research will contribute new knowledge to the asset management field in the road maintenance domain by providing a framework that is able to differentiate effective and efficient maintenance strategies from effective and inefficient ones. / Ph. D.
14

Measurement Of Differential Photon-jet Cross Section From 7 Tev Pp Collisions In The Cms Experiment At The Lhc

Ocalan, Kadir 01 March 2012 (has links) (PDF)
Prompt photons are produced primarily by quark-gluon compton scattering and quark-anti-quark annihilation mechanisms that their measurements are driven by several motivations at hadron colliders. Measurement of prompt photons can be used for probing perturbative Quantum Chromodynamics (pQCD). Prompt photons are produced in the final states of important decays providing evidence for low mass Higgs boson and new physics searches. Compact Muon Solenoid (CMS) is one of the multi-purpose experiments conducted at the Large Hadron Collider (LHC) to study the Standard Model (SM) physics including prompt photons and new theories in proton-proton collisions. In this thesis, photon reconstruction is discussed along with the photon identification methods in the CMS experiment. Photon efficiency measurements are presented as an important ingredient for photon+jet cross section measurement. Photon High Level Trigger (HLT) efficiencies, reconstruction (RECO) efficiencies, and identification (ID) efficiencies are presented that are measured from collision data recorded by the CMS detector and Monte Carlo simulation data. Efficiency corrected differential photon+jet cross section measurement results are presented in this study. The collision data used in this thesis corresponds to 2.2 /fb integrated luminosity collected by the CMS detector at a center-of-mass energy of 7 TeV from 2011 LHC proton-proton collision running.
15

Συγκριτική αξιολόγηση μονάδων διανομής της ΔΕΗ με την περιβάλλουσα ανάλυση δεδομένων

Κάρτας, Άγγελος 25 February 2010 (has links)
Η παρούσα εργασία πραγματεύεται το πρόβλημα της συγκριτικής αξιολόγησης των Μονάδων Διανομής της ΔΕΗ, και ειδικότερα των 14 Περιοχών της Διεύθυνσης Περιφέρειας Πελοποννήσου – Ηπείρου, με τη βοήθεια της μεθόδου περιβάλλουσας ανάλυσης δεδομένων, της DEA (Data Envelopment Analysis). Οι εξεταζόμενες Περιοχές είναι: Αγρίνιο, Αίγιο, Άρτα, Ζάκυνθος, Ιωάννινα, Καλαμάτα, Κέρκυρα, Κεφαλονιά, Κόρινθος, Ναύπλιο, Πάτρα, Πύργος, Σπάρτη και Τρίπολη. Η ΔΕΗ είναι η μοναδική εταιρεία διανομής ηλεκτρικής ενέργειας στη χώρα, η οποία έχει στην ιδιοκτησία της το δίκτυο διανομής και είναι υπεύθυνη για τη διανομή της ηλεκτρικής ενέργειας σε όλη την ελληνική επικράτεια. Η κάθε Περιοχή αποτελεί καταρχήν ανεξάρτητη οικονομική – διοικητική μονάδα, η οποία έχει αποστολή την ανάπτυξη, την συντήρηση και την λειτουργία του Δικτύου του γεωγραφικού χώρου ευθύνης της, καθώς και την παροχή πρόσβασης σ’ αυτό προς όλους του δικαιούμενους, σύμφωνα με τις σχετικές διατάξεις του Κώδικα Διαχείρισης Δικτύου. Η επίτευξη της αποστολής αυτής θα πρέπει να γίνεται με την καλύτερη δυνατή διαχείριση και αξιοποίηση των πόρων που διαθέτει η κάθε Περιοχή. Ως εισροές για κάθε Περιοχή είναι η εργασία (αριθμός των μισθωτών), ο κύριος εξοπλισμός (δίκτυα διανομής και μετασχηματιστές διανομής) και τα λειτουργικά έξοδα (ελέγξιμες δαπάνες εκμετάλλευσης). Ο Κώδικας Διαχείρισης Δικτύου δίνει ιδιαίτερη σημασία στην ποιότητα της παρεχόμενης ενέργειας και εξυπηρέτησης προς τους πελάτες. Για τον λόγο αυτό, υιοθετούνται επίσης ως εισροές, αντιπροσωπευτικά τους μεγέθη όπως: αριθμός βλαβών στο δίκτυο διανομής και χρόνος αποκατάστασης αυτών, καθώς και χρόνοι παροχών (μελέτη & κατασκευή). Ως εκροές, για μια Περιοχή Διανομής είναι ο αριθμός των πελατών (Χαμηλής Τάσης και Μέσης Τάσης), και η αντίστοιχη πωληθήσα ηλεκτρική ενέργεια. Η σχετική αποδοτικότητα των Περιοχών υπολογίσθηκε με βάση την δυνατότητά τους να μειώσουν τις εισροές με δεδομένα τα υφιστάμενα επίπεδα εκροών (προσανατολισμός στην εισροή). Τα δεδομένα που χρησιμοποιήθηκαν αφορούν στοιχεία για το έτος 2007. Χρησιμοποιήθηκε το λογισμικό Warwick DEA Software, (Warwick Business School, Warwick University, UK). Επίσης υπολογίσθηκαν οι συντελεστές συσχέτισης Pearson και Kendall, προκειμένου να εξεταστεί η ύπαρξη πιθανών συσχετίσεων μεταξύ των δεικτών αποδοτικότητας που προκύπτουν από την εφαρμογή της μεθόδου DEA και των απλών δεικτών αποδοτικότητας, ορισμένοι από τους οποίους χρησιμοποιούνται από τη ΔΕΗ, εκτιμούν όμως μεμονωμένους μόνο παράγοντες των Μονάδων. Από την ανάλυση των δεδομένων προέκυψαν τα ακόλουθα, (τα οποία δεν υιοθετούνται απαραίτητα από την ΔΕΗ): • Γενικά η αποδοτικότητα των Περιοχών είναι σχετικά υψηλή (>80%), πλην μιας Περιοχής. • Ο κύριος εξοπλισμός των Περιοχών (δίκτυο διανομής και μετασχηματιστές διανομής) και οι υπηρεσίες που προσφέρουν στους πελάτες τους (αριθμός πελατών και πωληθήσα ηλεκτρική ενέργεια) αποτελούν καθοριστικούς παράγοντες για την καταρχήν κατάταξή τους με βάση την τεχνική τους αποδοτικότητα. • Λαμβάνοντας όμως υπόψη στη μελέτη και άλλα κριτήρια, όπως οι ελέγξιμες δαπάνες, η ποιότητα της παρεχόμενης ενέργειας και η ποιότητα των παρεχόμενων υπηρεσιών, προκύπτει διαφοροποίηση στην αρχική κατάταξη των μη αποδοτικών Περιοχών, οι οποίες εν γένει βελτιώνουν την αποδοτικότητά τους, εκτός από τρεις περιοχές, οι οποίες παραμένουν στάσιμες. • Εξετάζοντας την αποδοτικότητα κλίμακας (σύγκριση της τεχνικής αποδοτικότητας κάθε Περιοχής, υπό κλίμακα σταθερών και μεταβλητών αποδόσεων), προκύπτει ότι υπάρχει επίπτωση του μεγέθους της κλίμακας στην παραγωγικότητα της αποτιμώμενης Περιοχής σε 6 Περιοχές, (αποδοτικότητα κλίμακας < 1). • Ορισμένοι από τους απλούς δείκτες αποδοτικότητας, οι οποίοι χρησιμοποιούνται και από τη ΔΕΗ, έχουν σημαντική συσχέτιση με τους δείκτες αποδοτικότητας που προκύπτουν από την εφαρμογή της μεθόδου DEA και μπορούν να εξηγήσουν την βαρύτητα ορισμένων παραγόντων στην διαμόρφωση της τεχνικής αποδοτικότητας των Μονάδων. Δεν παύουν όμως αυτοί οι απλοί δείκτες να εκτιμούν μεμονωμένους μόνο παράγοντες των Μονάδων, χωρίς να μπορούν να εκτιμήσουν την συνολική τεχνική αποδοτικότητα, όπως κάνει η μεθοδολογία DEA. • Η μέθοδος DEA μπορεί να αποτελέσει ένα βασικό και χρήσιμο εργαλείο πληροφόρησης και κατεύθυνσης για την ιεραρχία των Περιοχών, χωρίς όμως απαραίτητα να αποτελεί πανάκεια για τη λήψη αποφάσεων, αφήνοντας κατ’ αυτό τον τρόπο περιθώρια πρωτοβουλιών στη διοίκηση των Μονάδων. Η μέθοδος DEA συμβάλλει επίσης στην ανάπτυξη ενός εσωτερικού ανταγωνισμού μεταξύ των Μονάδων Διανομής. Περαιτέρω έρευνα με την εφαρμογή της μεθόδου σε δεδομένα περισσότερων ετών (π.χ. πενταετία), θα οδηγούσε σε ποιο ασφαλή και αξιόπιστα αποτελέσματα, λαμβάνοντας υπόψη κατ’ αυτό τον τρόπο και την εξέλιξη – πορεία των Περιοχών στο χρόνο. Η έρευνα θα μπορούσε επίσης να εφαρμοστεί για όλες της Περιοχές της Διανομής (59 Περιοχές) και να προκύψουν συγκριτικά αποτελέσματα για τις 5 Περιφερειακές Διευθύνσεις της Γενικής Διεύθυνσης Διανομής. / The present thesis deals with the problem of comparative evaluation of Distribution Districts of Power Public Corporation (PPC), and more specifically the 14 Districts of Peloponnese – Epirus Region Department, with the use of DEA (Data Envelopment of Analysis). The examined Districts are: Aegio, Agrinio, Arta, Corfu, Ioannina, Kalamata, Kefalonia, Korinthos, Nauplio, Patras, Pyrgos, Sparti, Tripoli and Zakynthos. PPC is the only company of electric energy distribution in the country, which is the ownership of the distribution network. Every District constitutes an independent economic–administrative unit, which has the mission of development, operation and maintenance of its network. It is also responsible to assure the access to the network of the beneficiaries (consumers & producers), according to the Distribution Network Operation Code. As inputs for each District are the work (personnel), the main equipment (distribution network and distribution transformers) and the functional expenses (controllable expenses). The Distribution Network Operation Code gives particular importance in the quality of provided energy and service to the customers. For this reason, they are adopted also as inputs: the number of network interruptions and the duration of interruptions, as well as the connection time to the network (study and construction). As outputs for each District are the number of customers (Low Voltage and Medium Voltage) and the supplied energy. The relative efficiency of Districts was calculated based on their possibility to decrease their inputs keeping their outputs constant (input orientation). The data that were used concern the year 2007. The Warwick DEA Software used for the calculations (Warwick Business School, Warwick University, UK). The Pearson and Kendall correlation coefficient were also calculated and the DEA technical efficiencies were compared with simple indices of efficiency, which PPC uses. From the analysis of data resulted following, (that are not necessarily adopted by PPC): • Generally the Districts efficiency is relatively high (> 80%), except one District. • The main equipment of Districts (distribution network and distribution transformers) and the offered services to their customers (number of customers and supplied energy) constitute decisive factors for their initial classification based on their technical efficiency. • Taking into consideration more criteria, as the controllable expenses, the quality of provided energy and the quality of provided services, result differentiation in the initial classification of not efficient Districts, what in general improve their efficiency, apart from three Districts, what remain stagnant. • Examining the scale efficiency (comparison of technical efficiency of each District, under variable and constant returns to scale), it results that exists effect of scale size in the productivity of 6 Districts, (scale efficiency < 1). • Some of simple indices of efficiency, which are also used by PPC, have important correlation with the DEA efficiencies and may explain the importance of some factors in the configuration of technical efficiency of Districts. However these simple indices continue to estimate only individual factors of Districts and not the total technical efficiency, as DEA does. • DEA can be a basic and useful tool of information and direction for the Districts Directors, without however be panacea for the decision-making, leaving in this way margins of initiatives in the Districts administration. DEA also contributes to the promotion of internal competition between the Distribution Districts.
16

Indicadores de eficiência de produção: uma análise na indústria petroquímica

Adami, Gustavo 23 December 2015 (has links)
Submitted by Patrícia Valim Labres de Freitas (patricial) on 2016-03-30T19:29:12Z No. of bitstreams: 1 Gustavo Adami.pdf: 2445130 bytes, checksum: d010b74234328835418d4d0ff2a01f40 (MD5) / Made available in DSpace on 2016-03-30T19:29:12Z (GMT). No. of bitstreams: 1 Gustavo Adami.pdf: 2445130 bytes, checksum: d010b74234328835418d4d0ff2a01f40 (MD5) Previous issue date: 2015-12-23 / Nenhuma / Características existentes no processo de produção da indústria de fluxo contínuo, particularmente a petroquímica, requerem que a medição de eficiência inclua características diferentes da indústria de produção intermitente, tais como a maneira de quantificação dos produtos finais e a natureza das perdas que são consideradas no cálculo da eficiência de produção. Indicadores de eficiência global de produção tipicamente são derivados do OEE (Overall Effective Equipment), proposto por Nakajima (1988) para a indústria de produção intermitente e, por vezes, são utilizados em indústrias de produção contínua sem uma análise prévia de suas limitações. Doze indicadores identificados na literatura foram analisados e comparados com características do processo de produção da indústria petroquímica, obtidos a partir da revisão teórica e de entrevistas com profissionais e pesquisadores dessa indústria. Dessa análise identificou-se que o indicador OAE (Overall Asset Efficiency) apresenta maior aderência em relação à classificação de perdas e às características do processo de manufatura da indústria petroquímica. Os resultados de eficiência global de produção obtidos através da utilização do OAE foram confrontados com os provenientes do OEE e do TEEP (Total Effective Equipment Productivity), com base em dados reais de uma empresa localizada no Pólo Petroquímico do Rio Grande do Sul. Os resultados obtidos através do cálculo de eficiência utilizando o indicador selecionado OAE, se mostraram mais descritivos da realidade da empresa quando comparados com aqueles atualmente utilizados. Outras práticas que geram interferências sobre o cálculo do OEE também foram identificadas nas entrevistas. Ainda, foi identificada a necessidade de uma discussão mais ampla no sentido de melhor definir os conceitos de capacidade e nível de atividade na indústria petroquímica e sua estimação operacional para fins de análise de eficiência, bem como, a incorporação de termos relativos à eficiência de insumos e custeio na análise de eficiência operacional global dessa indústria. / Due to singular characteristics present in the production of continuous flow process industry, especially petrochemical, efficiency measurement require different features of intermittently producing industry, such as how to quantify the final products and the cause of the losses that are considered in the calculation of production efficiency. Production efficiency indicators are typically derived from the OEE (Overall Equipment Effective) proposed by Nakajima (1988) for intermittent production industry, they are sometimes used in continuous manufacturing industries without a prior analysis of their limitations. Twelve indicators identified in the literature were analyzed and compared with features of the petrochemical industry production process, obtained from theoretical review and interviews with professionals and researchers in this industry. This analysis identified that the indicator OAE (Overall Asset Efficiency) has a better production losses structure and fits the characteristics of petrochemical manufacturing process. The results of overall production efficiency obtained using the OAE were compared with results from OEE and TEEP (Total Effective Equipment Productivity), based on manufacturing data from a company located in Rio Grande do Sul petrochemical complex. The results obtained from the efficiency calculation utilizing the selected indicator OAE, are more descriptive of the company situation when compared to those currently used. Other practices that causes interference on the calculation of OEE were also identified in the interviews. It was also identified the necessity for a broader discussion in order to better define the concepts of capacity and activity level in the petrochemical industry and also the operational way define them in order to make analysis of efficiency as well as the incorporation of terms concerning the efficiency of inputs and costing the analysis of overall operational efficiency of this industry.
17

美國政府機關實施全面品質管理之研究 / The Study of The Development of Total Quality Management in

羅淑琴, Lo, Chun Chin Unknown Date (has links)
多年來公部門受到了雙重的拘束:一是,預算被刪減;二是,處在需提供更多更好的公共服務的壓力之下。通常,公部門在面對上述資源受限、責任要求愈來愈多的環境時,典型的作法就是精減人力及減少計畫。但這是否為解決困境的良方,仍有待研究。學者Osborne及Gaebler在「新政府運動」一書中,認為最好的解決途徑是尋求「更好的治理形態」,即政府應調整本身的體質、增進效能、滿足顧客,使機關能在最低成本下運作。在一片「再造政府」、「再生工程」及「組織精減」聲中,當今的企業體與公部門組織,已意識到只有提供高品質的產品與服務,才能化解組織的存續危機。而全面品質管理便是一條能幫助組織渡過危機的革命性管理途徑,它與傳統管理實務在管理哲學、管理原則、管理焦點、績效評量、確保品質手段、管理結構、及改進的堅持方面都大不相同。全面品質管理是一種管理哲學,它的主要觀念可摘要為四點:經由組織過程中不斷的改進而致力於品質、經由資訊分享與將決策授權到最低的可能層級,轉換組織文化以鼓勵員工投入與賦予員工活力、創造與維持供應者與顧客的關係、使用資料蒐集與統計理論評量績效中的變異。全面品質管理實施時,應有相關的配合措施:建立品質測量系統、使其能與預算及資源系統相結合、調整人力資源系統、注重員工之訓練與發展等。
18

我國金融控股公司子銀行經營績效之研究 / -資料包絡法之應用

林盈鑫, Lin,ing-shin Unknown Date (has links)
資料包絡分析法乃是利用數學規劃模式求取決策單位之相對效率,故本研究針對本文針對競爭激烈之金控環境下,14至15家金控子銀行進行推估其經營效率。 銀行經營效率評估,主要以財務比率法、資料包絡法及隨機生產(或成本)邊界法。財務比率法大多利用單一投入與產出之比值,不符合生產函數之理論架構;DEA已經針對投入與產出之關係,作一嚴謹的分析,而能推估數個投入與產出之效率指標,此一效率指標,較能評估各廠商之經營績效。本文運用Farrell對於多項投入及多項產出效率衡量的概念,去推估各金控子銀行從1999年至2004年的經營效率,並建議這些銀行如何去配置最佳技術效率組合。 本研究的結論得出公營金控公司子銀行的績效不如民營金控子銀行來的佳。且金控公司子銀行未來應加強創新,增進風險管理的能力,促使銀行、證券及保險平台的結合,以便提高競爭力。 / Data Envelopment Analysis (DEA) is a mathematical programming approach to accessing relative efficiencies within a group of Decision Making Units (DMUS). therefore this research controls the environment in view of this article in view of the competition intense gold next the bank to carry on,14 to 15 Financial company bankings pushes estimates its management efficiency.   The bank management efficiency appraised, mainly by Financial Ratio Approachs, Data Envelopment Approachs and The Stochastic production (or cost) Frontier Approachs. The financial ratio Approachs mostly uses the sole investment with to deliver the ratio, does not conform to theory of overhead construction the production function; DEA already aimed at the investment with to deliver the relations, made a rigorous analysis, but could push estimates several investments with to deliver the efficiency target. This efficiency target, comparatively can appraise management achievements various merchants. This article utilizes Farrell delivers the efficiency weight regarding many investments and many items the concept, pushes estimates various Jin K'ungtzu the bank from 1999 to 2004 management efficiency, and suggested how these banks do dispose the best technical efficiency combination.   This research conclusion obtains the public-operated gold to control the company sub- bank the achievements to be inferior to privately operated Financial company bankings comes good. Also the gold will control the company sub- bank future to be supposed to strengthen the innovation, will promote the risk management the ability, will urge the bank, the negotiable securities and insures the platform the union, in order to enhancement competitive ability.
19

Novel Materials, Grid Design Rule, and Characterization Methods for Multi-Junction Solar Cells

January 2012 (has links)
abstract: This dissertation addresses challenges pertaining to multi-junction (MJ) solar cells from material development to device design and characterization. Firstly, among the various methods to improve the energy conversion efficiency of MJ solar cells using, a novel approach proposed recently is to use II-VI (MgZnCd)(SeTe) and III-V (AlGaIn)(AsSb) semiconductors lattice-matched on GaSb or InAs substrates for current-matched subcells with minimal defect densities. CdSe/CdTe superlattices are proposed as a potential candidate for a subcell in the MJ solar cell designs using this material system, and therefore the material properties of the superlattices are studied. The high structural qualities of the superlattices are obtained from high resolution X-ray diffraction measurements and cross-sectional transmission electron microscopy images. The effective bandgap energies of the superlattices obtained from the photoluminescence (PL) measurements vary with the layer thicknesses, and are smaller than the bandgap energies of either the constituent material. Furthermore, The PL peak position measured at the steady state exhibits a blue shift that increases with the excess carrier concentration. These results confirm a strong type-II band edge alignment between CdSe and CdTe. The valence band offset between unstrained CdSe and CdTe is determined as 0.63 eV±0.06 eV by fitting the measured PL peak positions using the Kronig-Penney model. The blue shift in PL peak position is found to be primarily caused by the band bending effect based on self-consistent solutions of the Schrödinger and Poisson equations. Secondly, the design of the contact grid layout is studied to maximize the power output and energy conversion efficiency for concentrator solar cells. Because the conventional minimum power loss method used for the contact design is not accurate in determining the series resistance loss, a method of using a distributed series resistance model to maximize the power output is proposed for the contact design. It is found that the junction recombination loss in addition to the series resistance loss and shadowing loss can significantly affect the contact layout. The optimal finger spacing and maximum efficiency calculated by the two methods are close, and the differences are dependent on the series resistance and saturation currents of solar cells. Lastly, the accurate measurements of external quantum efficiency (EQE) are important for the design and development of MJ solar cells. However, the electrical and optical couplings between the subcells have caused EQE measurement artifacts. In order to interpret the measurement artifacts, DC and small signal models are built for the bias condition and the scan of chopped monochromatic light in the EQE measurements. Characterization methods are developed for the device parameters used in the models. The EQE measurement artifacts are found to be caused by the shunt and luminescence coupling effects, and can be minimized using proper voltage and light biases. Novel measurement methods using a pulse voltage bias or a pulse light bias are invented to eliminate the EQE measurement artifacts. These measurement methods are nondestructive and easy to implement. The pulse voltage bias or pulse light bias is superimposed on the conventional DC voltage and light biases, in order to control the operating points of the subcells and counterbalance the effects of shunt and luminescence coupling. The methods are demonstrated for the first time to effectively eliminate the measurement artifacts. / Dissertation/Thesis / Ph.D. Electrical Engineering 2012
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球員在合約年及非合約年績效—以NBA為例 / The athletics' efficiency performance before and after signing a new multi-year contract: using NBA as an example.

邱咏平 Unknown Date (has links)
本研究使用資料包絡分析法衡量NBA球員之績效值,並探討球員在簽訂複數年合約前後與績效之關聯性,是否有Stiroh(2002)提出之合約年效應,並進而比較NBA官方提供績效值與DEA法計算出之球員績效值何者對於球員薪資具有較佳的解釋能力。 本研究取用2000年至2011年共11年間曾經歷合約到期並再次向球團簽訂複數年合約的184名球員做為樣本;實證結果發現,在控制年齡、年資、提前續約與否、球員位置及先發球員與否後整體技術效率方面及球員每分鐘平均績效值顯示在球員簽約前績效有顯著提高之現象; NBA官方提供績效值與純技術效率簽約前後係數也是負的,雖然未達到統計上顯著水準,因此,本研究結果顯示NBA球員在簽約新約前的確有合約週期現象,亦即為爭取較佳合約球員在簽約前會刻意表現較佳之績效。 此外,根據Vuong Test比較NBA官方提供績效值與DEA法計算出之績效值和球員每分鐘績效值與薪資關聯性的測試結果,顯示由官方提供之績效值對薪資關聯性較高,說明目前NBA官方提供之績效值仍然是球團用來與球員薪資的談判重要參考指標之一。 / The research applies Data Envelopment Analysis to examine the NBA players’ efficiency performance before and after signing a new multi-year contract, and whether there exists the Contract Cycle Effect that suggested by Stiroh (2002). The research also tries to compare NBA efficiency score and DEA efficiency score to test which has a higher association with salary. The samples selected 184 NBA players who signed a new multi-year contract from 2000 to 2011. After controlling the players’ age, seniority, extension, position and starting or not, the empirical results denote that DEA total efficiency score and the NBA efficiency per minute indicate a higher efficiency score before signing a new contract, The NBA official efficiency score and DEA technical efficiency score also reveal a negative coefficient before and after new contract singed, although the statistical test didn’t reach the significant level. The results imply that NBA players do exist the Contract Cycle Effect phenomenon that players will perform better efficiency in order to get a better contract. The Vuong test results reveal that the official NBA efficiency score has a higher association with salary comparing with DEA efficiency score. The finding suggests that the official efficiency score is one of the major references for the NBA teams on salary arbitration.

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