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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.
631

Aerodynamic Modeling of an Unmanned Aerial Vehicle Using a Computational Fluid Dynamics Prediction Code

Rose, Isaac D. 27 April 2009 (has links)
No description available.
632

Continuous improvement and operations strategy: focus on six sigma programs

Anand, Gopesh J. 19 September 2006 (has links)
No description available.
633

Kinetic modelling simulation and optimal operation of fluid catalytic cracking of crude oil: Hydrodynamic investigation of riser gas phase compressibility factor, kinetic parameter estimation strategy and optimal yields of propylene, diesel and gasoline in fluid catalytic cracking unit

John, Yakubu M. January 2018 (has links)
The Fluidized Catalytic Cracking (FCC) is known for its ability to convert refinery wastes into useful fuels such as gasoline, diesel and some lighter products such as ethylene and propylene, which are major building blocks for the polyethylene and polypropylene production. It is the most important unit of the refinery. However, changes in quality, nature of crude oil blends feedstock, environmental changes and the desire to obtain higher profitability, lead to many alternative operating conditions of the FCC riser. There are two major reactors in the FCC unit: the riser and the regenerator. The production objective of the riser is the maximisation of gasoline and diesel, but it can also be used to maximise products like propylene, butylene etc. For the regenerator, it is for regeneration of spent or deactivated catalyst. To realise these objectives, mathematical models of the riser, disengage-stripping section, cyclones and regenerator were adopted from the literature and modified, and then used on the gPROMS model builder platform to make a virtual form of the FCC unit. A new parameter estimation technique was developed in this research and used to estimate new kinetic parameters for a new six lumps kinetic model based on an industrial unit. Research outputs have resulted in the following major products’ yields: gasoline (plant; 47.31 wt% and simulation; 48.63 wt%) and diesel (plant; 18.57 wt% and simulation; 18.42 wt%) and this readily validates the new estimation methodology as well as the kinetic parameters estimated. The same methodology was used to estimate kinetic parameters for a new kinetic reaction scheme that considered propylene as a single lump. The yield of propylene was found to be 4.59 wt%, which is consistent with published data. For the first time, a Z-factor correlation analysis was used in the riser simulation to improve the hydrodynamics. It was found that different Z factor correlations predicted different riser operating pressures (90 – 279 kPa) and temperatures as well as the riser products. The Z factor correlation of Heidaryan et al. (2010a) was found to represent the condition of the riser, and depending on the catalyst-to-oil ratio, this ranges from 1.06 at the inlet of the riser to 0.92 at the exit. Optimisation was carried out to maximise gasoline, propylene in the riser and minimise CO2 in the regenerator. An increase of 4.51% gasoline, 8.93 wt.% increase in propylene as a single lump and 5.24 % reduction of carbon dioxide emission were achieved. Finally, varying the riser diameter was found to have very little effect on the yields of the riser products.
634

Knowledge-based Lean Six Sigma Maintenance System for Sustainable Buildings

Al Dairi, Jasim S.S., Khan, M. Khurshid, Munive-Hernandez, J. Eduardo 27 June 2016 (has links)
Yes / Purpose– This paper develops a Knowledge-based (KB) System for Lean Six Sigma (LSS) Maintenance in environmentally Sustainable Buildings (Lean6-SBM). Design/methodology/approach– The Lean6-SBM conceptual framework has been developed using the rule base approach of KB system and joint integration with Gauge Absence Prerequisites (GAP) technique. A comprehensive literature review is given for the main pillars of the framework with a typical output of GAP analysis. Findings– Implementation of LSS in the sustainable building maintenance context requires a pre-assessment of the organisation’s capabilities. A conceptual framework with a design structure is proposed to tackle this issue with the provision of an enhancing strategic and operational decision making hierarchy. Research limitations/implications– Future research work might consider validating this framework in other type of industries. Practical implications– Maintenance activities in environmentally sustainable buildings must take prodigious standards into consideration and, therefore, a robust quality assurance measure has to be integrated. Originality/value– The significance of this research is to present a novel use of hybrid KB/GAP methodologies to develop a Lean6-SBM system. The originality and novelty of this approach will assist in identifying quality perspectives while implementing different maintenance strategies in the sustainable building context. / Ministry of Defence Engineering Services (Sultanate of Oman)
635

Precise Trajectory Calculation for Launchers: A MATLAB – Simulink Modeling Approach / Noggrann banberäkning för bärraketer med MATLAB och Simulink

Barale, Matéo January 2024 (has links)
Optimizing launcher trajectories is essential for effective mission planning, and specialized software like ASTOS provide an initial, precise overview. However, as launcher development progresses, there is a growing need for the creation of an autonomous flight trajectory software that offers greaterflexibility in adjusting simulation parameters and better represents actual, real-life trajectories. Thisreport introduces an initial version of a comprehensive six-degree-of-freedom launcher trajectory calculation software developed using MATLAB and Simulink. The emphasis is on the development strategy, encompassing discussions on dynamics equations, essential features, and crucial models necessary for accurate simulations. Real-world scenarios often deviate from optimized trajectories, and the software addresses these deviations using sensitivity analysis through Monte Carlosimulations, enabling a thorough examination of uncertainties in input parameters and their impact on trajectories. The article delves into the establishment of the dispersion analysis tool and offers suggestions for further enhancements for both the Simulink model and this dispersion analysis tool. / Optimering av flygbanor är avgörande för effektiv uppdragsplanering, och specialiserad programvara som ASTOS ger en initial, exakt översikt. Men när flygbanans utveckling fortskrider finns det ett växande behov av att skapa en autonom flygbana som erbjuder större flexibilitet när det gäller attjustera simuleringsparametrar och bättre representerar faktiska, verkliga banor. Den här rapporten introducerar en initial version av en omfattande beräkningsprogramvara utvecklad med MATLAB och Simulink för sex frihetsgraders lanseringsbana. Tyngdpunkten ligger på utvecklingsstrategin, som omfattar diskussioner om dynamikekvationer, väsentliga funktioner och avgörande modeller som är nödvändiga för exakta simuleringar. Scenarier i verkligheten avviker ofta från optimerade banor, och programvaran adresserar dessa avvikelser med känslighetsanalys genom Monte Carlo-simuleringar,vilket möjliggör en grundlig undersökning av osäkerheter i inmatningsparametrar och deras påverkan på banor. Rapporten går in i skapandet av spridningsanalysverktyget och erbjuder förslag till ytterligare förbättringar för både Simulink-modellen och detta dispersionsanalysverktyg.
636

Assessment of Climate Change Impacts in the Six Nations of the Grand River Reserve / Climate Change and Six Nations

Deen, Tariq Adel January 2024 (has links)
Warming climate will affect communities across Canada. Many of these communities do not have the adaptive capacity to deal with climate change related challenges. Indigenous communities are believed to be disproportionally affected by climate change because of the lack of adequate infrastructure, and historical and political obstacles that limit their overall adaptive capacity. Therefore, climate change data and information are required to understand the full extent to which these communities are exposed to climate risks. Many past studies in the literature have outlined the effects of climate change at large spatial scales. While these studies are important for understanding the broad effects of climate change, they are not useful for community or local adaptation planning. Ultimately, climate change impacts will be felt at a local level. Hence, high resolution climate change impact studies are urgently needed to capture the realities of these effects in greater detail and to provide relevant data and information at local and community levels, in particular for marginalized and Indigenous communities. Using observed meteorological and hydrologic data, high-resolution downscaled future climate simulations, and a process-based hydrologic model, this thesis explored the physical impacts of climate change on the Six Nations of the Grand River (Six Nations) reserve, which is the largest (by population) Indigenous community in Canada and the seventh largest in the United States and Canada. Changing climate conditions and extreme climate trends in the Six Nations reserve were explored using the widely used ETCCDI (Expert Team on Climate Change Detection and Indices) extreme climate indices. Results indicated a warming and wetting trend in Six Nations, with the temperature rising by 3°C to 6°C by the end of the century and changes in seasonal precipitation. Extreme high temperature and precipitation indices will increase, causing potential human health impacts and increased flooding hazards for the community. A warming climate directly impacts the hydrological cycle and patterns. Analysis conducted using the Coupled Groundwater and Surface-Water Flow Model (GSFLOW) found that the McKenzie Creek - an important water provider for Six Nations - is sensitive to climate change due to its reliance on precipitation. Furthermore, study results showed that winter precipitation and streamflow are projected to increase, and snowpack water content is expected to decrease. These changes in streamflow will cause earlier winter-spring flooding events. Furthermore, agricultural production may be affected by reduced spring soil moisture recharge. Additionally, GSFLOW projected little to no change in late spring and summer streamflow which resulted in low water availability (Ptot-ET) during the growing season. Water availability was further examined by assessing future Blue Water (BW) and Green Water (GW) scarcity in the McKenzie Creek watershed. The water footprint method was used to calculate BW and GW scarcity. Study results showed that under current levels of water usage, BW scarcity would be “low” in the future. However, BW scarcity would increase to “significant” levels in the future, if water users started to withdraw more water for consumption, assuming maximum water withdrawal allocation (i.e., 0.47 m3s-1). This level of BW scarcity has the potential to cause ecological degradation and exacerbate water quality issues in the McKenzie Creek watershed. GW scarcity showed a steadily increasing trend throughout the 21st century due to climate warming. Spatial analysis showed that the western portion of the McKenzie Creek watershed may experience slightly higher levels of GW water scarcity in the future because of the lower water holding capacity of the soil. This may cause water users to withdraw more BW resources in western upstream areas, thereby decreasing BW available for downstream communities, including the Six Nations. Such disparity in water use among Indigenous and non-Indigenous communities may affect community relationships and social cohesion in the area. This thesis provides decision makers in Six Nations and more broadly in the McKenzie Creek watershed area with relevant climate change impact data and information that can be used in future climate change adaptation planning, disaster risk mitigation, and water resources management. Moreover, the results highlight the need for a comprehensive climate change vulnerability assessment of the Six Nations. / Thesis / Doctor of Philosophy (PhD)
637

Die geskiedenis van grondbesit in Distrik Ses tot 1984 met spesiale verwysing na die invloed van die Groepsgebiedewet na 1966

Laubscher, C. J. (Constant Johannes) 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: District Six originated in the eighteen fifties on neighbouring wine farms close to Cape Town's city centre. The first inhabitants were Europeans, but were later joined by free slaves. By 1849 the total number of inhabitants was 2943 and as a municipal area became known as the sixth district of Cape Town. Over the years District Six developed an own unique cosmopolitan character and despite a stigma as a backward residential area District Six developed as a multiracial community with its own vibrant spirit. By 1966 there were 3700 properties of which 56% were owned by Whites, 26% by Coloureds and 18% by Indians. In the same year the area had 21 schools and 17 places of worship. One of the main causes of physical deterioration was overpopulation. The occupancy figure by the 1850's was approximately 2,5 persons per habitable room. Overcrowding led to subletting of even the smallest rooms and resulted in gross exploitation of tenants, horrific crime and moral decay, all of which contributed to the slum status of the area. In 1962 the City of Cape Town devised a pilot plan for the rehabilitation of the area, but this plan was never implemented. Years of neglect of municipal services worsened the degredation of many historic buildings as well as decent living conditions for its residents. In 1962 the Group Areas Board recommended that District Six be declared a Coloured Group Area. The N.P. government rejected this recommendation and on 11 February 1966 through Proclamation 43, declared 94 hectares of the traditional District Six as an area for White occupation. Between 1965 and 1975 the government froze all property transactions in District Six to enable them to plan the redevelopment of the area. The state made financial offers to property owners, but only 10% accepted these. The majority declined these and blamed this on inflexible property valuations of the state. By 1980 the state had spent R25 million on the acquisition of properties in District Six. Government demolition of structures took place between 1968 and 1982 and resulted in the flattenning of most buildings except for a few churches. Expropriated Coloured and Indian residents were removed to the newly created residential areas on the Cape Flats. Although some previous residents of District Six were happy with their accommodation most objected to the high bond repayments on their new homes, higher transport cost to work and the breakdown of existing communities. The biggest opposition to the declaration of District Six as an area for White occupation came from local groups, namely: The Friends of District Six and the District Six Residents', Rent and Ratepayers Association (RRR). Opposition political parties and the press used the physical and mental suffering of the residents to challenge the government. The redevelopment of District Six was characterised by continous changes to proposed plans. In 1964 the government appointed the Niemand Committee to investigate the replanning and redevelopment of District Six. In 1970 a master plan for redevelopment was recommended . In 1974 the first properties were sold to white people by the government. In 1975 the neighbouring Walmer Estate was declared a Coloured Group Area and three years later District Six was renamed as Zonnebloem. In 1979 parts of the neighbouring Woodstock and Salt River were declared Coloured Group Areas. In 1982 the Presidents Council recommended that part of District Six be returned to the Coloured community, but the government rejected this and in October 1982 year the first whites settled in District Six. The following year a part of District Six was declared Coloured area. / AFRIKAANSE OPSOMMING: Distrik Ses het in die vyftigerjare van die negentiende eeu op aanliggende wynplase van Kaapstad ontstaan. Aanvanklik het Blankes van verskillende nasionaliteite daar gevestig en later het vrygestelde slawe die inwonertal laat toeneem. Teen 1849 was die inwonertal ongeveer 2943 en in 1867 het die gebied bekend geword as die sesde distrik van Kaapstad . Distrik Ses het n eiesoortige en unieke kosmopolitiese karakter ontwikkel. Ten spyte van n stigma van agterlikheid het die gebied n borrelende en veelrassige gemeenskap gehad. In 1966 was daar ongeveer 3700 eiendomme in Distrik Ses waarvan 56% aan Blankes, 26% aan Kleurlinge en 18% aan Indiers behoort het. Teen 1966 was daar 21 skole en sewentien plekke van godsdienstige aanbidding in die gebied. Oorbevolking was een van die grootste oorsake van verval in die gebied. In die vyftigerjare was die besettingsyfer van geboue ongeveer 2,5 persone per bewoonbare vertrek. Die gevolg was onderverhuring, gruwelike uitbuiting van huurders, misdaad en sedelike verval wat aan die gebied n slumstatus besorg het. Jarelange verwaarlosing van munisipale dienste het tot vervaI van gebouestrukture en Iewenstoestande gelei. Die stadsraad se loodsplan vir opruiming in 1962 is nooit geimplementeer nie. Die Groepsgebiederaad het in 1962 aanbeveel dat die gebied as n Kleurling-groepsgebied verklaar moes word. Ten spyte van die aanbeveling is 94 hektaar van die tradisionele Distrik Ses op 11 Februarie 1966 volgens Proklamasie 43 van 1966 as n Blanke Groepsgebied verklaar. Die regering het vanaf 1965 tot 1975 aile eiendomstransaksies in Distrik Ses gevries om sodoende die herontwikkeling van die gebied te beplan. Ongeveer 10% van die eienaars het die staat se aanbod vir hul eiendom aanvaar. Die meeste het egter beswaar gemaak teen die staat se onbuigsame skattings. Teen 1980 het die staat R25 miljoen bestee aan die verkryging Slopingswerk in Distrik Ses het tussen 1968 en 1982 plaasgevind. Byna aIle geboue is gesloop en slegs enkele kerke is behou. Inwoners is na verskeie woonbuurte op die Kaapse Vlakte verskuif Alhoewel sommige vorige inwoners van Distrik Ses tevrede was met hulle nuwe woonplekke was die meeste ontevrede oor die hoe verbandkoste van nuwe wonings, hoer reiskoste en die verbrokkeling van gemeenskappe. Die grootste opposisie teen die Blankverklaring van Distrik Ses was The Friends of District Six en die District Six Residents', Rent and Ratepayers' Association (RRR). Opposisiepolitieke partye en die pers het die regering se rassebeleid aangeval deur te konsentreer op die ontberinge van die inwoners. Die herontwikkeling van Distrik Ses is gekenmerk deur voortdurende verandering. In 1964 is die Niemand-komitee aangestel om die herbeplanning en herontwikkeling van Distrik Ses te ondersoek. In 1970 is n meesterplan vir die ontwikkeling van Distrik Ses aanbeveel. In Julie 1974 het die regering die eerste eiendom in Distrik Ses aan Blankes verkoop. In 1975 is die aangrensende Walmer Estate tot Kleurlinggroepsgebied verklaar. Distrik Ses is in 1978 herdoop en R9 rniljoen is bewillig vir die rehabilitasieskema. In 1979 is dele van die aangrensende Woodstock en Soutrivier tot Kleurlinggroepsgebiede verklaar. In 1980 is ri gewysigde plan vir die ontwikkeling van Distrik Ses voorgele. In 1981 het die regering die Presidentsraad se aanbeveling dat n gedeelte van Distrik Ses aan die Kleurlinggemeenskap teruggegee moes word, verwerp. In Oktober 1982 het die eerste blankes in Distrik Ses gevestig. In 1983 is n gedeelte van Distrik Ses as Kleurlinggebied verklaar.
638

An Introduction to Selected Character Pieces for Piano by Robert Muczynski

Oh, Joo Young January 2016 (has links)
Robert Muczynski (1929-2010), composer, pianist, and educator, is a noteworthy American musician from our time. His prowess as a pianist undoubtedly accounts for the striking number of pieces he wrote for the piano, namely, one concerto, preludes, sonatas, suites, a toccata, and variations. Out of a total of forty-eight pieces with opus numbers, seventeen are for solo piano. This document contains an overview of Muczynski's life as a composer and musician, with an emphasis on his solo piano compositions. The body of the document traces sources of Muczynski's compositional style, especially the influence of Alexander Tcherepnin, his composition teacher and mentor, and Sergei Prokofiev. An analysis of some of Muczynski's shorter piano solo pieces follows: Six Preludes, op. 6, Suite for Piano, op. 13, and Toccata, op. 15. This analysis demonstrates that Muczynski's short piano pieces often exhibit a persistent focus on one generative musical idea within each piece, usually consisting of unifying etude-like material. For variety and color, he relies on frequent changes of metric pulse, sudden accents, highly chromatic harmony and melody, and an extreme range of sound. These stylistic traits are consistent with those previously identified by other scholars in his larger piano compositions.
639

Analysis of information security risks and protection management requirements for enterprise networks

Saleh, Mohamed Saad Morsy January 2011 (has links)
With widespread of harmful attacks against enterprises' electronic services, information security readiness of these enterprises is becoming of increasing importance for establishing the required safe environment for such services. Various approaches are proposed to manage enterprise information security risks and to assess its information security readiness. These approaches are, however, not adequate to manage information security risks, as all required information security components of its structural and procedural dimensions have not considered. In addition, current assessment approaches lack numerical indicators in assessing enterprise information security readiness. Furthermore, there is no standard approach for analysing cost versus benefit in selecting recommended protection measures. This thesis aims at contributing to the knowledge by developing comprehensive Enterprise Information Security Risk Management (EISRM) framework that integrates typical approaches for information security risk management, and incorporates main components of key risk management methodologies. In addition, for supporting phases of the proposed EISRM framework, analytical models for enterprise information security readiness assessment and cost-benefit analysis are developed. The practical evaluation, using the proposed enterprise information security readiness assessment model has been performed depending on a developed investigation form that used to investigate nine enterprises inside Saudi Arabia. The results demonstrate the effectiveness of the model in assessing and comparing enterprises information security readiness at all levels of the model, using numerical indicators and graphical representations. The EISRM framework and the analytical models presented in this research can be used by enterprises as single point of reference for assessing and cost effectively improving their information security readiness.
640

人力資源管理在變革中所承擔的角色與功能--以某跨國公司推動六標準差為例

朱承平, Chu, Cheng Ping Unknown Date (has links)
企業為求成長與永續經營變革乃必須的歷程,而徵諸許多變革歷程的資料,人力資源管理所扮演的角色與功能已經日益突顯,從以往執行者角色,逐漸蛻化成推動變革者,策略夥伴的角色。   而全球化、新科技、人力市場結構的急速變遷以及市場回應速度,更使得人力資源管理在變革中所承擔的功能越趨複雜,實有必要深入探討。 1) 將變革人資與六標準差一並做研究,恐會備多力分,宜更加緊約,俾 能更邏輯。 2) 部分資料引用係次級資料宜加以改進。 3) 資料求證上因受到限制,致未能完全達到測試期求結果。 4) 應在財務成效外繼續研討組織變革與策略在變革上做更進一步研究。 5) 較偏重訓練對變革的影響,宜擴及至其他人資功能在變革過程角色 的研究。 / For the rapid growth and sustainable management purposes, Change has become an inevitable process in many businesses, however, the role of Human Resource to participate in managing change now is more prominent than ever from time to time, from the implementer in the earlier stage, gradually becomes the change facilitator and even now the partner during the strategic decision stage. Globalization, new technology, the fast changing of human market infrastructure, and the need of quick response for market situation, enable the function and role of Human Resource to be more complicated, and this is main purpose for this study, to study the role and function of Human Resource on managing change. 1) It was rather difficult to integrate change ,sigma and Human Resource together to complete this thesis, and more logic process should be address. 2) Some data and literature are from sub level, should be improved. 3) It was a little regret due to the condition and limitation during the survey process, the accuracy of some result are below the expectation, should be improved then as we make the similar study. 4) Most result are based on financial performance, should be expanded to the organizational development and strategy. 5) Too much emphasized and focus on the impact of training,and some other HR functions like performance management,moral and motivation should be further studied.

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