• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • 1
  • 1
  • Tagged with
  • 5
  • 5
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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.
1

A Study on Certification Mechanism Design for Deep Sea Water Applications

Luo, Wen-yan 03 August 2006 (has links)
Characterized as rich mineral substances, low temperature, few bacteria, and stability with numerous implementation aspects on aquaculture, food, drinking, and leisure, the development of deep sea water (DSW) has become a governmental policy and a new industry. The eastern region in Taiwan owns outstanding pumping DSW conditions and a prosperity on its industry applications is expected if the development project goes well. However, a design on the inspection mechanism is critical to the industry development due to water's indifference characteristics. This study aims at inspection problems relevant with certification mechanism to construct an overall certification operation system. An investigation is designed to understand the current inspection system status while implementation for the use of lab function requirements, inspection operation, and product inspection process considerations. A management conceptual mechanism is also provided for DSW industry development in the future
2

Object detection and pose estimation from natural features for augmented reality in complex scenes

SIMOES, Francisco Paulo Magalhaes 07 March 2016 (has links)
Submitted by Alice Araujo (alice.caraujo@ufpe.br) on 2017-11-29T16:49:07Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TeseFinal_fpms.pdf: 108609391 bytes, checksum: c84c50e3c8588d6c85e44f9ac6343200 (MD5) / Made available in DSpace on 2017-11-29T16:49:07Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TeseFinal_fpms.pdf: 108609391 bytes, checksum: c84c50e3c8588d6c85e44f9ac6343200 (MD5) Previous issue date: 2016-03-07 / CNPQ / Alignment of virtual elements to the real world scenes (known as detection and tracking) relying on features that are naturally present on the scene is one of the most important challenges in Augmented Reality. When it goes to complex scenes like industrial scenarios, the problem gets bigger with the lack of features and models, high specularity and others. Based on these problems, this PhD thesis addresses the question “How to improve object detection and pose estimation from natural features for AR when dealing with complex scenes problems?”. In order to answer this question, we need to ask ourselves “What are the challenges that we face when developing a new tracker for real world scenarios?”. We begin to answer these questions by developing a complete tracking system that tackles some characteristics typically found in industrial scenarios. This system was validated in a tracking competition organized by the most important AR conference in the world, called ISMAR. During the contest, two complementary problems to tracking were also discussed: calibration, procedure which puts the virtual information in the same coordinate system of the real world, and 3D reconstruction, which is responsible for creating 3D models of the scene to be used for tracking. Because many trackers need a pre-acquired model of the target objects, the quality of the generated geometric model of the objects influences the tracker, as observed on the tracking contest. Sometimes these models are available but in other cases their acquisition represents a great effort (manually) or cost (laser scanning). Because of this we decided to analyze how difficult it is today to automatically recover 3D geometry from complex 3D scenes by using only video. In our case, we considered an electrical substation as a complex 3D scene. Based on the acquired knowledge from previous experiments, we decided to first tackle the problem of improving the tracking for scenes where we can use recent RGB-D sensors during model generation and tracking. We developed a technique called DARP, Depth Assisted Rectification of Patches, which can improve matching by using rectified features based on patches normals. We analyzed this new technique under different synthetic and real scenes and improved the results over traditional texture based trackers like ORB, DAFT or SIFT. Since model generation is a difficult problem in complex scenes, our second proposed tracking approach does not depend on these geometric models and aims to track texture or textureless objects. We applied a supervised learning technique, called Gradient Boosting Trees (GBTs) to solve the tracking as a linear regression problem. We developed this technique by using image gradients and analyzing their relationship with tracking parameters. We also proposed an improvement over GBTs by using traditional tracking approaches together with them, like intensity or edge based features which turned their piecewise constant function to a more robust piecewise linear function. With the new approach, it was possible to track textureless objects like a black and white map for example. / O alinhamento de elementos virtuais com a cena real (definido como detecção e rastreamento) através de características naturalmente presentes em cena é um dos grandes desafios da Realidade Aumentada. Quando se trata de cenas complexas, como cenários industriais, o problema se torna maior com objetos pouco texturizados, alta especularidade e outros. Com base nesses problemas, esta tese de doutorado aborda a questão "Como melhorar a detecção de objetos e a estimativa da sua pose através de características naturais da cena para RA ao lidar com problemas de cenários complexos?". Para responder a essa pergunta, precisamos também nos perguntar: Quais são os desafios que enfrentamos ao desenvolver um novo rastreador para cenários reais?". Nesta tese, começamos a responder estas questões através da criação de um sistema de rastreamento completo que lida com algumas características tipicamente encontradas em cenários industriais. Este sistema foi validado em uma competição de rastreamento realizada na principal conferência de RA no mundo, chamada ISMAR. Durante a competição também foram discutidos dois problemas complementares ao rastreamento: a calibração, procedimento que coloca a informação virtual no mesmo sistema de coordenadas do mundo real, e a reconstrução 3D, responsável por criar modelos 3D da cena. Muitos rastreadores necessitam de modelos pré-adquiridos dos objetos presentes na cena e sua qualidade influencia o rastreador, como observado na competição de rastreamento. Às vezes, esses modelos estão disponíveis, mas em outros casos a sua aquisição representa um grande esforço (manual) ou custo (por varredura a laser). Devido a isto, decidimos analisar a dificuldade de reconstruir automaticamente a geometria de cenas 3D complexas usando apenas vídeo. No nosso caso, considerou-se uma subestação elétrica como exemplo de uma cena 3D complexa. Com base no conhecimento adquirido a partir das experiências anteriores, decidimos primeiro resolver o problema de melhorar o rastreamento para as cenas em que podemos utilizar sensores RGB-D durante a reconstrução e o rastreamento. Foi desenvolvida a técnica chamada DARP, sigla do inglês para Retificação de Patches Assistida por Informação de Profundidade, para melhorar o casamento de características usando patches retificados a partir das normais. A técnica foi analisada em cenários sintéticos e reais e melhorou resultados de rastreadores baseados em textura como ORB, DAFT ou SIFT. Já que a reconstrução do modelo 3D é um problema difícil em cenas complexas, a segunda abordagem de rastreamento não depende desses modelos geométricos e pretende rastrear objetos texturizados ou não. Nós aplicamos uma técnica de aprendizagem supervisionada, chamada Gradient Boosting Trees (GBTs) para tratar o rastreamento como um problema de regressão linear. A técnica foi desenvolvida utilizando gradientes da imagem e a análise de sua relação com os parâmetros de rastreamento. Foi também proposta uma melhoria em relação às GBTs através do uso de abordagens tradicionais de rastreamento em conjunto com a regressão linear, como rastreamento baseado em intensidade ou em arestas, propondo uma nova função de predição por partes lineares mais robusta que a função de predição por partes constantes. A nova abordagem permitiu o rastreamento de objetos não-texturizados como por exemplo um mapa em preto e branco.
3

Microbial population dynamics in indigenous olive wastewater biofilms

Hoekstra, Dirk Tjalling January 2007 (has links)
Thesis (MTech (Food Technology))--Cape Peninsula University of Technology, 2007 / The olive industry in South Africa, although small compared to the rest of the world, is rapidly expanding and producing increased volumes of wastewater on an annual basis that could in future develop into a major environmental problem. Olive mill wastewater (OMWW) and table olive wastewater (TOWW) are characterised by high chemical oxygen demand (COD), biological oxygen demand (BOD) and phenolic content that are toxic to the environment. Due to the nature of olive wastewater (OWW), its irresponsible and unregulated environmental release will result in oxygen depletion, nutrient enrichment and accumulation of toxic compounds in receiving water bodies that ultimately disrupts aquatic and terrestrial ecosystems. An estimated 3500 - 4500 tons of olives are processed on an annual basis by 51 farmers .in the Western Cape. Economic forecasts predict a steady growth, i.e. increased production and processing of olives in the South African olive industry, in the future due to consumer demand. These production increases will consequently lead to increased volumes of wastewater production, which would, in tum, require an expansion of treatment capacity of the wastewater prior to release. Two South African olive factories were chosen for this study: Buffet Olives, situated in Dal Josefat (Paarl), that produces table olives and Vesuvio Estate on Sorento farm (Wellington) that produce extra-virgin olive oil. Preliminary COD determinations showed that indigenous OWW biofilms within a rotating biological contactor set-up reduced the COD from TOWW and OMWW by 47% and 32%, respectively, over a l0-day period. These preliminary results strongly suggested that biofilms indigenous to OWW have the potential to remediate the pollution problems of OWW. However, the overall aim of this study was to determine how sustainable the application of indigenous biofilms in the OWW are over two production seasons and whether it would be feasible to apply and develop these naturally occurring biofilms as an effective bioremediation tool to reduce the COD and polyphenol content of OWW.
4

Scheduling coal handling processes using metaheuristics

Conradie, David Gideon 21 April 2008 (has links)
The operational scheduling at coal handling facilities is of the utmost importance to ensure that the coal consuming processes are supplied with a constant feed of good quality coal. Although the Sasol Coal Handling Facility (CHF) were not designed to perform coal blending during the coal handling process, CHF has to blend the different sources to ensure that the quality of the feed supplied is of a stable nature. As a result, the operation of the plant has become an extremely complex process. Consequently, human intelligence is no longer sufficient to perform coal handling scheduling and therefore a scheduling model is required to ensure optimal plant operation and optimal downstream process performance. After various attempts to solve the scheduling model optimally, i.e. with exact solution methods, it was found that it is not possible to accurately model the complexities of CHF in such a way that the currently available exact solvers can solve it in an acceptable operational time. Various alternative solution approaches are compared, in terms of solution quality and execution speed, using a simplified version of the CHF scheduling problem. This investigation indicates that the Simulated Annealing (SA) metaheuristic is the most efficient solution method to provide approximate solutions. The metaheuristic solution approach allows one to model the typical sequential thoughts of a control room operator and sequential operating procedures. Thus far, these sequential rules could not be modelled in the simultaneous equation environment required for exact solution methods. An SA metaheuristic is developed to solve the practical scheduling model. A novel SA approach is applied where, instead of the actual solution being used for neighbourhood solution representation, the neighbours are indirectly represented by the rules used to generate neighbourhood solutions. It is also found that the initial temperature should not be a fixed value, but should be a multiple of the objective function value of the initial solution. An inverse arctan-based cooling schedule function outperforms traditional cooling schedules as it provides the required diversification and intensification behaviour of the SA. The scheduling model solves within 45 seconds and provides good, practically executable results. The metaheuristic approach to scheduling is therefore successful as the plant complexities and intricate operational philosophies can be accurately modelled using the sequential nature of programming languages and provides good approximate optimal solutions in a short solution time. Tests done with live CHF data indicate that the metaheuristic solution outperforms the current scheduling methodologies applied in the business. The implementation of the scheduler will lead to a more stable factory feed, which will increase production yields and therefore increase company profits. By reducing the amount of coal re-handling (in terms of throw-outs and load-backs at mine bunkers), the scheduler will reduce the coal handling facility’s annual operating cost by approximately R4.6 million (ZAR). Furthermore, the approaches discussed in this document can be applied to any continuous product scheduling environment. Additional information available on a CD stored at Level 3 of the Merensky Library. / Dissertation (MEng (Industrial Engineering))--University of Pretoria, 2011. / Industrial and Systems Engineering / unrestricted
5

Zukunft in Sachsen: Berufseinstieg, Branchen, Perspektiven

Zanger, Cornelia, Genz, Christian 04 January 2012 (has links)
Sachsen hat Zukunft Hochschulabsolventinnen und -absolventen stehen im Freistaat Sachsen eine Vielzahl beruflicher Möglichkeiten offen. Damit der Einstieg in den sächsischen Arbeitsmarkt erfolgreich gelingt, haben die Mitarbeiterinnen und Mitarbeiter des Career Service der TU Chemnitz ihre Erfahrungen aus der täglichen Arbeit gebündelt und stellen sie nun allen Studierenden und Interessierten zur Verfügung Das Buch bietet von der Jobrecherche bis zur Gehaltsverhandlung wertvolle Tipps zum Bewerbungsprozess. Daran anschließend werden in 15 Branchenreports Perspektiven und Einstiegsmöglichkeiten sowohl auf Bundesebene als auch für den Freistaat Sachsen vorgestellt. Außerdem schildern zahlreiche Persönlichkeiten aus Politik, Wirtschaft und Hochschule ihre Sicht auf das Thema Zukunft in Sachsen und geben individuelle Karrieretipps. / Career Prospects in Saxony The Free State of Saxony offers graduates a variety of career opportunities. The Career Service of Chemnitz University of Technology offers advice on how to access Saxony’s job market most successfully by making its experience and expertise of its daily work available. The book provides valuable information on the application process, ranging from job research to salary negotiation. 15 industry reports introduce career prospects in Saxony as well as nationwide. In addition, leading figures and renowned personalities from the fields of politics, society and academia express their views on career perspectives in Saxony.

Page generated in 0.1129 seconds