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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.
1

A multi-disciplinary study of aerodynamic surface smoothness requirements of aircraft based on V2500 turbofan nacelle data to reduce operating cost

Kundu, Ajoy Kumar January 1999 (has links)
No description available.
2

Replacement decisions with multiple stochastic values and depreciation

Adkins, Roger, Paxson, D. 14 July 2016 (has links)
Yes / We develop an analytical real-option solution to the after-tax optimal timing boundary for a replaceable asset whose operating cost and salvage value deteriorate stochastically. We construct a general replacement model, from which seven other particular models can be derived, along with deterministic versions. We show that the presence of salvage value and tax depreciation significantly lowers the operating cost threshold that justifies (and thus hastens) replacement. Although operating cost volatility increases defer replacement, increases in the salvage value volatility hasten replacement, albeit modestly, while increases in the correlation between costs and salvage value defer replacement. Reducing the tax rate or depreciation lifetime, or allowing an investment tax credit, yield mixed results. These results are also compared with those of less complete models, and deterministic versions, showing that failure to consider several stochastic variables and taxation in the replacement process may lead to sub-optimal decisions.
3

Modernising underground compressed air DSM projects to reduce operating costs / Christiaan Johannes Roux Kriel

Kriel, Christiaan Johannes Roux January 2014 (has links)
Growing demand for electricity forces suppliers to expand their generation capacity. Financing these expansion programmes results in electricity cost increases above inflation rates. By reducing electricity consumption, additional supply capacity is created at lower costs than the building of conventional power stations. Therefore, there is strong justification to reduce electricity consumption on the supplier and consumer side. The mining and industrial sectors of South Africa consumed approximately 43% of the total electricity supplied by Eskom during 2012. Approximately 10% of this electricity was used to produce compressed air. By reducing the electricity consumption of compressed air systems, operating costs are reduced. In turn this reduces the strain on the South African electricity network. Previous energy saving projects on mine compressed air systems realised savings that were not always sustainable. Savings deteriorated due to, amongst others, rapid employee turnover, improper training, lack of maintenance and system changes. There is therefore a need to improve projects that have already been implemented on mine compressed air systems. The continuous improvement of equipment (such as improved control valves) and the availability of newer technologies can be used to improve existing energy saving strategies. This study provides a solution to reduce the electricity consumption and operating costs of a deep level mine compressed air system. This was achieved by modernising and improving an existing underground compressed air saving strategy. This improvement resulted in a power saving of 1.15 MW; a saving equivalent to an annual cost saving of R4.16 million. It was found that the improved underground compressed air DSM project realised significant additional electrical energy savings. This resulted in ample cost savings to justify the implementation of the project improvements. It is recommended that opportunities to improve existing electrical energy saving projects on surface compressed air systems are investigated. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014
4

Modernising underground compressed air DSM projects to reduce operating costs / Christiaan Johannes Roux Kriel

Kriel, Christiaan Johannes Roux January 2014 (has links)
Growing demand for electricity forces suppliers to expand their generation capacity. Financing these expansion programmes results in electricity cost increases above inflation rates. By reducing electricity consumption, additional supply capacity is created at lower costs than the building of conventional power stations. Therefore, there is strong justification to reduce electricity consumption on the supplier and consumer side. The mining and industrial sectors of South Africa consumed approximately 43% of the total electricity supplied by Eskom during 2012. Approximately 10% of this electricity was used to produce compressed air. By reducing the electricity consumption of compressed air systems, operating costs are reduced. In turn this reduces the strain on the South African electricity network. Previous energy saving projects on mine compressed air systems realised savings that were not always sustainable. Savings deteriorated due to, amongst others, rapid employee turnover, improper training, lack of maintenance and system changes. There is therefore a need to improve projects that have already been implemented on mine compressed air systems. The continuous improvement of equipment (such as improved control valves) and the availability of newer technologies can be used to improve existing energy saving strategies. This study provides a solution to reduce the electricity consumption and operating costs of a deep level mine compressed air system. This was achieved by modernising and improving an existing underground compressed air saving strategy. This improvement resulted in a power saving of 1.15 MW; a saving equivalent to an annual cost saving of R4.16 million. It was found that the improved underground compressed air DSM project realised significant additional electrical energy savings. This resulted in ample cost savings to justify the implementation of the project improvements. It is recommended that opportunities to improve existing electrical energy saving projects on surface compressed air systems are investigated. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014
5

Η δομή του κόστους των νοσοκομείων στην Ελλάδα : η επίδραση του παράγοντα της εκπαίδευσης (teaching impact cost) στο κόστος των πανεπιστημιακών νοσοκομείων της Ελλάδας / The cost structure fo Greek hospitals : the effect of teaching impact factor in the operating cost of Greek University hospitals

Θανάσας, Γεώργιος 12 April 2013 (has links)
Μια από τις κυριότερες δαπάνες, τις οποίες είναι αναγκαίο να πληρώσουν οι διάφορες χώρες, είναι αυτή για τις υπηρεσίες παροχής υγείας προς τους πολίτες. Από τα μέσα του προηγούμενου αιώνα (δεκαετία 1940), αρκετές προηγμένες χώρες του δυτικού κόσμου, ξεκίνησαν την αναμόρφωση στα συστήματα υγείας τους, αρχικά με την εισαγωγή των Οικονομικών της Υγείας και έπειτα με την Λογιστική Επιστήμη. Η ανάγκη αυτή προήλθε εξαιτίας της προσπάθειας συγκράτησης των δαπανών τους, μέσω και της μείωσης του λειτουργικού κόστους των Νοσοκομείων. Παράλληλα, ενέτειναν τις έρευνες τους όχι μόνο για τη διάρθρωση του λειτουργικού κόστους των Νοσοκομείων τους, αλλά και για τον προσδιορισμό ειδικότερων παραγόντων, οι οποίοι προσαυξάνουν το κόστος. Ένας από τους παράγοντες, οι οποίοι προσδιορίστηκαν, είναι και αυτός της εκπαίδευσης του μελλοντικού ιατρικού και νοσηλευτικού προσωπικού από τα Πανεπιστημιακά Νοσοκομεία. Στην ουσία, πρόκειται για το επιπρόσθετο ποσοστό κόστους το οποίο δαπανούν τα Πανεπιστημιακά Νοσοκομεία, έναντι των Γενικών, για την επιμόρφωση των φοιτητών των Ιατρικών και Νοσηλευτικών Σχολών, ώστε να μπορέσουν να στελεχώσουν μετέπειτα τον τομέα της Υγείας. Στην Ελλάδα, η αρχή της ένταξης της Λογιστικής Επιστήμης στα Νοσοκομεία έγινε με το Π.Δ. 143/2003. Παρόλο όμως το γεγονός της υποχρεωτικής εφαρμογής των αρχών και πρακτικών της Λογιστικής στα Ελληνικά Νοσοκομεία από την 1/1/2004, ελάχιστα είναι αυτά που τις εφάρμοζαν. Από το 2009, που η χώρα εισέρχεται στην οικονομική κρίση, η ανάγκη για διαφάνεια σε όλους τους τομείς των δημοσίων δαπανών καθίσταται επιτακτική και αναγκαία. Αυτό δεν άφησε ανεπηρέαστο τον τομέα της Υγείας και «επέβαλε» στα Νοσοκομεία την έκδοση οικονομικών καταστάσεων και καταστάσεων δαπανών. Η παρούσα διατριβή, πραγματεύεται τον προσδιορισμό του ποσοστού του επιπρόσθετου κόστους το οποίο αναλαμβάνουν τα Πανεπιστημιακά Νοσοκομεία, έναντι των αντίστοιχων Γενικών, στην Ελλάδα. Για τον προσδιορισμό του ποσοστού αυτού, λαμβάνονται υπόψη διάφοροι παράγοντες από την διεθνή βιβλιογραφία, οι οποίοι χρησιμοποιήθηκαν σε παρόμοιες μελέτες. Επίσης, στη παρούσα διατριβή παρουσιάζεται η δομή και οι παράγοντες εκείνοι, που επιδρούν στη διαμόρφωση του λειτουργικού κόστους των Πανεπιστημιακών Νοσοκομείων της Ελλάδας. Για τον προσδιορισμό αυτό, χρησιμοποιήθηκαν οικονομικά και λειτουργικά στοιχεία, τα οποία παραχωρήθηκαν από Πανεπιστημιακό Νοσοκομείο της Ελλάδας. / One of the main expenditure, that countries among world are required to pay, is that for the provision of health services to their citizens. From the middle of last century (decade 1940), several western countries, began to reform their health systems, initially with the introduction of the Health Economics and afterward introducing the Accounting Science in Hospitals. This need derived because of the effort to contain costs and by reducing the operating costs of Hospitals. At the same time, these countries developed their research not only in the structure of the operating costs of Hospitals, but also to identify specific factors that increases the cost. One of these factors were identified, and this is the education, by the Teaching Hospitals, of future medical and nursing staff. In essence it is the additional rate costs that are required to spend by the Teaching Hospitals, for the training of students of medical and nursing schools so that they can later be deployed by the Health Sector In Greece, the principle of inclusion of Accounting Science in Hospitals was done by Presidential decree 143/2003. Although the fact that the application of the principles and practices of Accounting by the Greek Hospitals was compulsory from 1/1/2004, few are those who practice it. Since 2009, when the country enters the economic crisis, the need for transparency in all areas of public spending is imperative and necessary. This is not left unaffected by the Health Sector and “forced” Greek Hospitals to issue financial and cost statements. This thesis deals with the determination of the percentage of additional costs that being undertaken by the Teaching Hospitals, opposite the General ones, in Greece. To determine this percentage, several factors from the international literature are taking into account and have been used in similar studies. Also, this thesis shows the structure and the factors that affect the configuration of the operating costs of Teaching Hospitals in Greece. For this assay, financial and operating data are used and were provided by a Teaching Hospital in Greece.
6

Balanço econômico da operação de semeadura da cultura da soja em diferentes arranjos espaciais / Economic balance of seeding operation of culture of soybean in different spatial dispositions

Tavares, Leandro Augusto Felix [UNESP] 14 December 2015 (has links)
Submitted by LEANDRO AUGUSTO FELIX TAVARES null (leandropekiki@hotmail.com) on 2016-01-21T02:09:43Z No. of bitstreams: 1 TESE LEANDRO FINAL.pdf: 1924418 bytes, checksum: 00b22b6beafcf0567713349857b8b0e4 (MD5) / Approved for entry into archive by Sandra Manzano de Almeida (smanzano@marilia.unesp.br) on 2016-01-21T13:42:09Z (GMT) No. of bitstreams: 1 tavares_laf_dr_bot.pdf: 1924418 bytes, checksum: 00b22b6beafcf0567713349857b8b0e4 (MD5) / Made available in DSpace on 2016-01-21T13:42:09Z (GMT). No. of bitstreams: 1 tavares_laf_dr_bot.pdf: 1924418 bytes, checksum: 00b22b6beafcf0567713349857b8b0e4 (MD5) Previous issue date: 2015-12-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Na busca pelo maior retorno financeiro para os produtores rurais, pesquisadores têm estudado diferentes métodos de produção, dentre os quais está a redução do espaçamento entre fileiras no momento da semeadura. Contudo é necessário a realização de balanço econômico para saber se é viável para os produtores a inclusão dessas novas técnicas de semeadura. Diante do exposto, o objetivo desse trabalho foi avaliar o efeito de diferentes sistemas de semeadura na cultura da soja semeada com semeadora-adubadora de precisão e de fluxo contínuo, bem como o seu balanço econômico. O experimento foi conduzido na área experimental das Fazendas de Ensino, Pesquisa e Extensão (FEPE) da Faculdade de Ciências Agronômicas, da Universidade Estadual Paulista “Júlio de Mesquita Filho” – UNESP, Campus de Botucatu. O delineamento experimental foi em blocos casualizados em esquema de arranjo fatorial 4x2, sendo 4 sistemas de semeadura [sistema de semeadura convencional (testemunha), sistema de semeadura cruzada, sistema de semeadura adensado e sistema de semeadura em fileira dupla] e 2 tipos de semeadora [Semeadora-adubadora de precisão e de fluxo contínuo], com quatro repetições. As características agronômicas avaliadas foram: altura de plantas e inserção de vagens, determinação da população final de plantas, determinação do teor de água dos grãos, determinação da massa de 1.000 grãos e determinação da produtividade. Foi avaliado também o dano mecânico em sementes por meio das análises de teste de verde rápido e teste de germinação. O balanço econômico foi realizado utilizando a metodologia de custo operacional das máquinas agrícolas descritas por MIALHE (1974) e ASABE (2006). Depois de realizada a análise se variância foi verificada diferença estatística para as todas as características agronômicas avaliadas no experimento. Verifica-se que houve diferença estatística em todas as características agronômicas avaliadas no experimento, constata-se também principal dos tipos de semeadora para as características produtividade e dano mecânico da cultura de soja, dessa forma observou-se que a semeadora de fluxo contínuo causou maior dano mecânico a semente do que a semeadora de precisão, logo também houve diferença estatística na produtividade da cultura da soja, em que quando a semeadura foi realizada com a semeadora de precisão a produtividade foi mais elevada. Avaliando os espaçamentos utilizados no estudo foi constatado que o espaçamento em fileira dupla obteve maior produção, diferindo estatisticamente dos demais arranjos de semeadura. Em relação ao custo total de produção observou-se que os arranjos de semeadura mais onerosos são os que é necessário realizar duas passadas na mesma área, são estes, sistema de plantio cruzado com as semeadoras de precisão e fluxo contínuo, sistema semeadura adensado com a semeadora de precisão. Na relação benefício/custo dos sistemas ficou constatado que o melhor arranjo de semeadura é o fileira dupla quando a operação foi realizada com a semeadora de precisão. / In an attempt to increase the financial return to farmers, researchers have studied diferente production methods such as the reduction of the spacing between rows during the sowing. However, a study of the economic balance is needed to know whether the use of this method at sowing is feasible for farmers. Therefore, the objective of this work was to evaluate the soybean crop as to the effect of different sowing systems using a precision and continuous flow seeder and as well as to evaluate the feasibility of these systems. The experiment was conducted in an experimental area from Fazendas de Ensino, Pesquisa e Extensão (FEPE) at Faculdade de Ciências Agronômicas from Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Botucatu campus. A randomized complete block design in a 4 [conventional seeding system (control), cross-seeding system, dense seeding system and seeding system in double row] x 2 (kind of seeder and fertilizer drill: precise and continuous flow) factorial arrangement with four repetitions in each treatment was used. The agricultural characteristics evaluated were plant height, string bean insertion, total plants counting, determination of water content in grains, determination of mass in 1,000 grains, and determination of productivity. The mechanical damage was also evaluated in seeds by the analyses of fast green test and germination test. Economic balance was found using the operating cost methodology of agricultural machines described by MIALHE (1974) and ASABE (2006). After conducted analysis of variance was verified statistical difference for all agronomic traits in the experiment. It is found that there were statistically significant differences in all agronomic traits in the experiment also is observed main types of seeder for the characteristics productivity and mechanical damage of soybean thus noted that the streaming seeder caused higher mechanical damage the seed of the sower of precision, so also was no statistical difference in the soybean yield, in that when the seeding was done with the precision seeder productivity was higher. Evaluating the spacing used in the study it was found that the spacing in double row obtained the highest production, differing from the other seeding arrangements. In relation to the total cost of production it was observed that the most costly seeding arrangements are that you must perform two passes in the same area, are these, crossed planting system with precision sowing machines, continuous flow, dense planting system with precision seeder. The benefit / cost of the systems it was found that the best seeding arrangement is the double row when the operation was carried out with a precision seeder.
7

Análise econômica de amostra representativa de propriedades produtoras de leite bovino em Rondonópolis - MT

Castro, Denyse Itacaramby de 13 May 2014 (has links)
Submitted by Simone Souza (simonecgsouza@hotmail.com) on 2017-10-30T13:30:00Z No. of bitstreams: 1 DISS_2014_Denyse Itacaramby de Castro.pdf: 767216 bytes, checksum: 39a5987d0ceef90883cb5c5be451a49a (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-11-08T13:13:20Z (GMT) No. of bitstreams: 1 DISS_2014_Denyse Itacaramby de Castro.pdf: 767216 bytes, checksum: 39a5987d0ceef90883cb5c5be451a49a (MD5) / Made available in DSpace on 2017-11-08T13:13:20Z (GMT). No. of bitstreams: 1 DISS_2014_Denyse Itacaramby de Castro.pdf: 767216 bytes, checksum: 39a5987d0ceef90883cb5c5be451a49a (MD5) Previous issue date: 2014-05-13 / A produção de leite no município de Rondonópolis tem apresentado um crescimento positivo ao longo dos últimos anos. Neste contexto, objetivou-se avaliar a estrutura do custo de produção da atividade leiteira em diferentes estratos de produção no município de Rondonópolis – MT, traçando assim, o perfil econômico da atividade em questão. Os dados primários utilizados na análise referem-se ao período de outubro de 2010 a setembro de 2011, sendo coletados durante o mês de setembro de 2011. A amostra dos produtores entrevistados foi calculada a partir da produção de leite do município de Rondonópolis, tendo como fonte IBGE/pesquisa trimestral do leite e foi proporcional à produção municipal em relação à produção total posteriormente dividida em estratos de produção de acordo com a distribuição do universo de produtores de leite do município de Rondonópolis. Estes estratos foram assim divididos: até 50 L/dia; de 51 a 100; de 101 a 200; de 201 a 500 e acima de 500 L/dia. Com um horizonte temporal de curto prazo, a metodologia utilizada para análise dos dados foi a do custo operacional de produção. Através da análise encontrou-se que as despesas formadoras do custo operacional efetivo são as que mais oneraram o custo final de produção da atividade leiteira e, por consequência, a reduzida margem líquida tanto na atividade leiteira como na produção de leite. Margem Bruta e Margem Líquida foram positivas em todos os estratos, significando que os entrevistados não têm motivos, no curto prazo, para abandonar a atividade. / Milk production in the municipality of Rondonópolis has shown positive growth over the past few years. In this context , we aimed to evaluate the structure of the production cost of milk production in different strata, tracing thus the economic profile of the activity in question . The primary data used in the analysis are for the period October 2010 to September 2011, and were collected during the month of September 2011. The sample of farmers interviewed was calculated from the production of milk in the municipality of Rondonópolis, having as source IBGE/quarterly survey of milk and was proportional to the municipal production in relation to total production subsequently divided into strata of production according to the distribution pattern of dairy farmers in the municipality of Rondonópolis . These strata were divided as follows: up to 50 L/day; 51-100; from 101 to 200 ; From 201 to 500 and above 500 L/day. With a short-term time horizon, the methodology used for data analysis was the operational cost of production. Through analysis it was found that the training costs of the actual operating costs are the most burdening the final production cost of milk production and, consequently, reduced net margin in both the dairy industry as the production of milk. Gross Margin and Net Margin were positive in all strata, meaning that respondents have no reason in the short term , to abandon the activity, however , the farmers are working at the limit .
8

Comparing the impact of internet of things and cloud computing on organisational behavior: a survey

García-Tadeo, Diego A., Reddy Peram, Dattatreya, Suresh Kumar, K., Vives, Luis, Sharma, Trishu, Manoharan, Geetha 01 January 2022 (has links)
Cloud computing is about delivery of different computing services involving databases, analytics, software, networking with the use of internet to enhance innovation, incorporate flexibility in resources and broaden profitability. However, Internet of Things (IoT) is an essential system for interrelating computer devices, digital machines, people and others which are offered with unique identifiers where data can be transferred with human involvement and wireless network. 42% of organisations in UK use cloud computing. The problem with cloud computing revolves around security and privacy issues as data is stored by a third party from inside or outside of the organisation leading to broken authentication, compromising of credentials and others. The use of IoT is vulnerable as it provides connectivity to devices, machines and people therefore, it needs to contain more storage that is made from cloud facilities. Survey has been conducted where primary quantitative method has been considered to obtain data from 101 managers of the organisation that has adopted cloud computing and IoT. However, 8 close-ended questions have been asked to 101 managers. Positivism philosophy has been used to make quantifiable observations along with descriptive design and others. The results and discussion will analyse responses of the respondents after conducting statistical analysis. However, research has been revolving around making a comparison between using cloud computing and IoT along with analysing organisational behaviour. / Revisión por pares
9

Simulation and optimization of MSF desalination process for fixed freshwater demand: Impact of brine heater fouling

Hawaidi, Ebrahim A.M., Mujtaba, Iqbal M. January 2010 (has links)
No description available.
10

Cost Optimization of Aircraft Structures

Kaufmann, Markus January 2009 (has links)
Composite structures can lower the weight of an airliner significantly. Due to the higher process complexity and the high material cost, however, the low weight often comes with a significant increase in production cost. The application of cost-effective design strategies is one mean to meet this challenge. In this thesis, a simplified form of direct operating cost is suggested as a comparative value that in combination with multidisciplinary optimization enables the evaluation of a design solution in terms of cost and weight. The proposed cost optimization framework takes into account the manufacturing cost, the non-destructive testing cost and the lifetime fuel consumption based on the weight of the aircraft, thus using a simplified version of the direct operating cost as the objective function. The manufacturing cost can be estimated by means of different techniques. For the proposed optimization framework, feature-based parametric cost models prove to be most suitable. Paper A contains a parametric study in which a skin/stringer panel is optimized for a series of cost/weight ratios (weight penalties) and material configurations. The weight penalty (defined as the specific lifetime fuel burn) is dependent on the fuel consumption of the aircraft, the fuel price and the viewpoint of the optimizer. It is concluded that the ideal choice of the design solution is neither low-cost nor low-weight but rather a combination thereof. Paper B proposes the inclusion of non-destructive testing cost in the design process of composite components, and the adjustment of the design strength of each laminate according to inspection parameters. Hence, the scan pitch of the ultrasonic testing is regarded as a variable, representing an index for the guaranteed material quality. It is shown that the cost for non-destructive testing can be lowered if the quality level of the laminate is assigned and adjusted in an early design stage. In Paper C and Paper D the parameters of the manufacturing processes are upgraded during the cost optimization of the component. In Paper C, the framework is extended by the cost-efficient adaptation of parameters in order to reflect the situation when machining an aluminum component. For different weight penalties, the spar thickness and stringer geometry of the provided case study vary. In addition, another cutter is chosen with regard to the modified shape of the stringer. In Paper D, the methodology is extended to the draping of composite fabrics, thus optimizing not only the stacking layup, but also the draping strategy itself. As in the previous cases, the design alters for different settings of the weight penalty. In particular, one can see a distinct change in fiber layup between the minimum weight and the minimum cost solution. Paper E summarizes the work proposed in Papers A-D and provides a case study on a C-spar component. Five material systems are used for this case study and compared in terms of cost and weight. The case study shows the impact of the weight penalty, the material cost and the labor rate on the choice of the material system. For low weight penalties, for example, the aluminum spar is the most cost-effective solution. For high weight penalties, the RTM system is favorable. The paper also discusses shortcomings with the presented methodology and thereby opens up for future method developments. / QC 20100723 / European Framework Program 6, project ALCAS, AIP4-CT-2003-516092 / Nationella flygtekniska forskningsprogrammet (NFFP) 4, project kostnadseffektiv kompositstruktur (KEKS)

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