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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.
31

"Simpsonovská aféra" a "annus horribilis" Příspěvek k proměnám obrazu britské královské rodiny na veřejnosti ve dvacátém století / The "Simpson Affair" and the "Annus horribilis" Contribution to the Changes of the Picture of the British Royal Family in the General Public in the 20th Century

Krausová, Markéta January 2015 (has links)
In this thesis the author analyses the changes in the view of the British Royal Family in general public during the 20th century. Given the extensiveness of the topic, the author focuses on two crisis situations - so called "Simpson Affair" - the abdication of King Edward VIII in 1936 and his relationship with divorced American Wallis Simpson, and so called "Annus Horribilis" - the divorce of the successor to the throne prince Charles and princess Diana Spencer. The author analyses changes in perception of the role of British Royal Family in life of British nation and its role within British general public. Author works with unpublished sources (mainly from the archive materials gathered from the sources of the Archive of the Ministry of Foreign Affairs of the Czech Republic and the National Archives in London - Kew, with published sources and extensive specialized literature mostly from British provenience. Keywords Great Britain, Monarchy, Royal Family, Edward VIII, Wallis Simpson, Elizabeth II, Prince Charles, Diana Spencer, General Public
32

Case study of a contract system : considering pulp prices from 1996-2006

Janstad, Tobias January 2007 (has links)
Södra Cell sells 1 900 000 ton pulp every year. Of this 490 000 tonne is sold with a contract system based on a pricing index called PIX NBSK. This index was started in 1996 and reflects the price of pulp from conferious forest. We study the NBSK PIX value of softwood from October 1996 to December 2006. People working in this branch known that there is strong periodicity in the prices. We use predictive analysis to see if clients can benefit from the periodicity and use the options in the contract system Södra offers today. We conclude that a drawback for the current contract system is that there are too many contracts in proportion to the duration time that is one year for all contracts. Using a time series model called ARMA we make successfull predictions the price difference between two contracts. Based on this prediction we change between these contracts, reducing the price with 0.81% in mean during 1997-2006. Due to the total turnover, if all clients would used such predictions during 1997-2006 Södra's income would have been reduced with 2.77 million USD a year in mean. The prices used before PIX are called list prices. The list prices seem to behave like the PIX index. Supposing that the same contract system we see in PIX today was used 1975-2006 with the list price as the base index I made a prediction of the list prices from 1986-2006. Thanks to my predictions, if I had been a client during this period and under mentioned considerations I would have been buying pulp to a price reduced with 0.57%. If clients had known the PIX between 1996-2006 in say 1995 Södra's contract system based on PIX would give them a price reduction that were 1.5% in mean during 1996-2006. Price reduction is not possible all years, but when it occurs it can be as big as 3% of the price. Suppose the clients always choose the contract with the lowest price and thereby get a reduced price over time. Then with 95% probability over a long period the price reduction is somewhere in between 0.4-2.7%. To strangle this price reduction possibility for the clients there are two ways to go: either reduce the number of contracts or extend the duration time of the contracts. To find a suitable duration time, we do spectral density estimation to get indications of which periods that are most important. From this we see that PIX index has a period of five years, wavelet approximated PIX index has 3.4 years and the list prices has a period of 5.6 years. This indicates that current duration time one year is too short. Therefore if it wouldn't effect Södra's clients, an extension of the duration time from one to five years would be good. If Södra don't extend the duration time of the contracts my recommendation is to have fewer contracts. The possibility to change between the contracts ''average last three months'' and ''average current month'' every other year is the weakest point of today's system. Therefore I recommend stop selling pulp to the contract ''average PIX last three months''. We can't prove any longterm difference between the contracts. If Södra chooses to have just one contract from this point of view it does not matter which one they choose. However, it seems like a good idea to follow the global market and therefore I recommend to choose ''average PIX current month'' rather than ''average PIX last three months'' which lags behind the market front. Since the price ''average current month'' is available at FOEX web page I think Södra should choose this contract if they decide to have only one contract. / Södra Cell säljer årligen 1 900 000 ton pappersmassa. Av denna mängd säljs 490 000 ton enligt ett kontraktsystem baserat på ett prisindex som heter PIX NBSK. Detta index introducerades 1996 och reflekterar priset på pappersmassa gjord av barrträd. Jag studerar priset på indexet från Oktober 1996 till December 2006. Dagens kontraktsystem är baserat på kontrakt med löptiden ett år. Jag undersöker om man kan prediktera prisskilllnaden mellan kontrakten, dra nytta att dagens löptid som bara är ett år och välja det kontrakt som ger det billigaste priset så ofta att priset över lång tid reduceras. När man predikterar gör man en uppskattningen av framtiden utifrån en modell av hur framtid beror på dåtid och nutid. Den modell jag har använt kallas ARMA. Denna tillsammans med priserna på pappersmassa från 1975 och framåt gav mig ett fruktbart sätt att förutsäga priserna. Resultatet blev ett pris reducerat med 0.81% i medel under perioden 1996-2006. Eftersom Södra ha så stor försäljningsvolym skulle de ha förlorat 2.27 miljoner dollar per ton i medel om alla kunder ha spekulerat utifrån den modellen jag använde. Om dagens kontraktsystem hade börjat användas 1975 med listpriserna som bas hade en kund som använt min prediktionsmetod fått ett pris reducerat med 0.57% under perioden 1986-2006. Om kunderna i förväg hade vetat priset under 1996-2001 gav det nuvarande systemet en reducerad medelintäkt med 1.5% av priset. Enskilda år reducerades intäkten med så mycket som 3%. Beräknar man konfidensintervall för prisreduktionerna så inser man att på lång sikt kommer dessa vara av storleksordningen 0.4-2.7% med sannolikheten 95%. Detta förutsatt att klienterna kan se in i framtiden. Siffran 2.7% alltså ett mått på hur stor risk man tar med dagens system. Jag tror inte att klienterna kommer reducera priset med 2.7% med nuvarande system, men det är en övre gräns. De gynsamma prediktionerna har sitt ursprung i att det finns periodicitet i priserna. Jag undersöker denna periodicitet med spektralanalys. Periodiciteten för PIX indexet är starkast kring 5 år. En wavelet-approximation av PIX-indexet hade störst periodicitet kring 3.4 år. Listpriserna hade starkast periodicitet kring 5.6 år. Detta indikerar att den nuvarande löptiden, ett år, är för kort. En lämpligare löptid för kontrakten är 5 år. Förmodligen är fem års löptid alltför lång tid att binda sig för många kunder. Därför föreslår jag att man reducerar antalet kontrakt istället. Den största svagheten i dagens system är den korta löptiden tillsammans med kontrakten ''average current month'' och ''average last three months''. Jag rekommenderar att man slutar erbjuda kontraktet ''average last three months''. Det allra säkraste är att endast erbjuda ett kontrakt. Vi har inte kunnat påvisa några skillnader över lång sikt mellan kontrakten såtillvida att något kontrakt skulle ge ett lägre medelpris än ett annat. Ur den aspekten är det godtyckligt vilket kontrakt man väljer, men det verkar vettigt att följa den globala marknaden. Därför är det eftersläpande kontraktet ''average PIX last three months'' inte att rekommendera, välj heller ''average PIX current month''. Ett annat argument för att välja ''average PIX current month'' är att dessa priser finns på FOEX hemsida och inga extra beräkningar behöver göras.
33

Case study of a contract system : considering pulp prices from 1996-2006

Janstad, Tobias January 2007 (has links)
<p>Södra Cell sells 1 900 000 ton pulp every year. Of this 490 000 tonne is sold with a contract system based on a pricing index called PIX NBSK. This index was started in 1996 and reflects the price of pulp from conferious forest. We study the NBSK PIX value of softwood from October 1996 to December 2006.</p><p>People working in this branch known that there is strong periodicity in the prices. We use predictive analysis to see if clients can benefit from the periodicity and use the options in the contract system Södra offers today. We conclude that a drawback for the current contract system is that there are too many contracts in proportion to the duration time that is one year for all contracts. Using a time series model called ARMA we make successfull predictions the price difference between two contracts. Based on this prediction we change between these contracts, reducing the price with 0.81% in mean during 1997-2006. Due to the total turnover, if all clients would used such predictions during 1997-2006 Södra's income would have been reduced with 2.77 million USD a year in mean.</p><p>The prices used before PIX are called list prices. The list prices seem to behave like the PIX index. Supposing that the same contract system we see in PIX today was used 1975-2006 with the list price as the base index I made a prediction of the list prices from 1986-2006. Thanks to my predictions, if I had been a client during this period and under mentioned considerations I would have been buying pulp to a price reduced with 0.57%.</p><p>If clients had known the PIX between 1996-2006 in say 1995 Södra's contract system based on PIX would give them a price reduction that were 1.5% in mean during 1996-2006. Price reduction is not possible all years, but when it occurs it can be as big as 3% of the price. Suppose the clients always choose the contract with the lowest price and thereby get a reduced price over time. Then with 95% probability over a long period the price reduction is somewhere in between 0.4-2.7%.</p><p>To strangle this price reduction possibility for the clients there are two ways to go: either reduce the number of contracts or extend the duration time of the contracts.</p><p>To find a suitable duration time, we do spectral density estimation to get indications of which periods that are most important. From this we see that PIX index has a period of five years, wavelet approximated PIX index has 3.4 years and the list prices has a period of 5.6 years. This indicates that current duration time one year is too short. Therefore if it wouldn't effect Södra's clients, an extension of the duration time from one to five years would be good.</p><p>If Södra don't extend the duration time of the contracts my recommendation is to have fewer contracts. The possibility to change between the contracts ''average last three months'' and ''average current month'' every other year is the weakest point of today's system. Therefore I recommend stop selling pulp to the contract ''average PIX last three months''.</p><p>We can't prove any longterm difference between the contracts. If Södra chooses to have just one contract from this point of view it does not matter which one they choose. However, it seems like a good idea to follow the global market and therefore I recommend to choose ''average PIX current month'' rather than ''average PIX last three months'' which lags behind the market front. Since the price ''average current month'' is available at FOEX web page I think Södra should choose this contract if they decide to have only one contract.</p> / <p>Södra Cell säljer årligen 1 900 000 ton pappersmassa. Av denna mängd säljs 490 000 ton enligt ett kontraktsystem baserat på ett prisindex som heter PIX NBSK. Detta index introducerades 1996 och reflekterar priset på pappersmassa gjord av barrträd. Jag studerar priset på indexet från Oktober 1996 till December 2006.</p><p>Dagens kontraktsystem är baserat på kontrakt med löptiden ett år. Jag undersöker om man kan prediktera prisskilllnaden mellan kontrakten, dra nytta att dagens löptid som bara är ett år och välja det kontrakt som ger det billigaste priset så ofta att priset över lång tid reduceras. När man predikterar gör man en uppskattningen av framtiden utifrån en modell av hur framtid beror på dåtid och nutid. Den modell jag har använt kallas ARMA. Denna tillsammans med priserna på pappersmassa från 1975 och framåt gav mig ett fruktbart sätt att förutsäga priserna. Resultatet blev ett pris reducerat med 0.81% i medel under perioden 1996-2006. Eftersom Södra ha så stor försäljningsvolym skulle de ha förlorat 2.27 miljoner dollar per ton i medel om alla kunder ha spekulerat utifrån den modellen jag använde.</p><p>Om dagens kontraktsystem hade börjat användas 1975 med listpriserna som bas hade en kund som använt min prediktionsmetod fått ett pris reducerat med 0.57% under perioden 1986-2006.</p><p>Om kunderna i förväg hade vetat priset under 1996-2001 gav det nuvarande systemet en reducerad medelintäkt med 1.5% av priset. Enskilda år reducerades intäkten med så mycket som 3%. Beräknar man konfidensintervall för prisreduktionerna så inser man att på lång sikt kommer dessa vara av storleksordningen 0.4-2.7% med sannolikheten 95%. Detta förutsatt att klienterna kan se in i framtiden. Siffran 2.7% alltså ett mått på hur stor risk man tar med dagens system. Jag tror inte att klienterna kommer reducera priset med 2.7% med nuvarande system, men det är en övre gräns.</p><p>De gynsamma prediktionerna har sitt ursprung i att det finns periodicitet i priserna. Jag undersöker denna periodicitet med spektralanalys. Periodiciteten för PIX indexet är starkast kring 5 år. En wavelet-approximation av PIX-indexet hade störst periodicitet kring 3.4 år. Listpriserna hade starkast periodicitet kring 5.6 år. Detta indikerar att den nuvarande löptiden, ett år, är för kort. En lämpligare löptid för kontrakten är 5 år.</p><p>Förmodligen är fem års löptid alltför lång tid att binda sig för många kunder. Därför föreslår jag att man reducerar antalet kontrakt istället. Den största svagheten i dagens system är den korta löptiden tillsammans med kontrakten ''average current month'' och ''average last three months''. Jag rekommenderar att man slutar erbjuda kontraktet ''average last three months''. Det allra säkraste är att endast erbjuda ett kontrakt. Vi har inte kunnat påvisa några skillnader över lång sikt mellan kontrakten såtillvida att något kontrakt skulle ge ett lägre medelpris än ett annat. Ur den aspekten är det godtyckligt vilket kontrakt man väljer, men det verkar vettigt att följa den globala marknaden. Därför är det eftersläpande kontraktet ''average PIX last three months'' inte att rekommendera, välj heller ''average PIX current month''. Ett annat argument för att välja ''average PIX current month'' är att dessa priser finns på FOEX hemsida och inga extra beräkningar behöver göras.</p>
34

Réforme de la péréquation financière et de la répartition des tâches : incidences du transfert du domaine des institutions pour personnes handicapées aux cantons /

Pralong, Frédéric. January 2007 (has links) (PDF)
Travail de mémoire. / En même temps: Travail de mémoire Chavannes-sur-Lausanne. Sur la p. de titre: Chaire politiques publiques et durabilité. Bibliogr.
35

Loajalita a spokojenost účastníků Street Dance Kemp s nabídkou služeb akce / Participant loyalty and satisfaction with services offered on Street Dance Kemp

Štrbíková, Barbara January 2014 (has links)
Participant loyalty and satisfaction with services offered on Street Dance Kemp Goal: Main goal of this thesis is to find a relationship between participant loyalty and satisfaction with services offered on Street Dance Kemp. Methods: In this thesis is used questionnaire and structured interview for obtaining data about participant satisfaction with services offered and about their loyalty to the event. Will be also examined the available competition in dance camps in Europe. To find a relationship between participant loyalty and satisfaction is used statistical method Kruskal-Wallis non-parametrical ANOVA. Results: Main result of this thesis is evaluation of the relationship between participant loyalty and satisfaction and future possible improvement of the services in order to get more loyal participants. Key words: sport event, street dance, hip-hop, questionnaire and interview, competition analysis, Kruskal-Wallis ANOVA
36

An Agent-Based Model of Ant Colony Energy and Population Dynamics: Effects of Temperature and Food Fluctuation

Xiaohui, Guo 01 August 2014 (has links)
The ant colony, known as a self-organized system, can adapt to the environment by a series of negative and positive feedbacks. There is still a lack of mechanistic understanding of how the factors, such as temperature and food, coordinate the labor of ants. According to the Metabolic Theory of Ecology (MTE), the metabolic rate could control ecological process at all levels. To analyze self-organized process of ant colony, we constructed an agent-based model to simulate the energy and population dynamics of ant colony. After parameterizing the model, we ran 20 parallel simulations for each experiment and parameter sweeps to find patterns and dependencies in the food and energy flow of the colony. Ultimately this model predicted that ant colonies can respond to changes of temperature and food availability and perform differently. We hope this study can improve our understanding on the self-organized process of ant colony.
37

Evaluation der Infrastrukturförderung in Regional-, Tourismus- und Verkehrspolitik der Schweiz : eine Fallstudie zur Region Visp-Saastal im Kanton Wallis /

Atmanagara, Jenny. January 2007 (has links) (PDF)
Univ., Diss.--Bern, 2007.
38

A criatividade matem?tica de John Wallis na obra Arithmetica Infinitorum: contribui??es para ensino de c?lculo diferencial e integral na licenciatura em matem?tica

Lopes, Gabriela Lucheze de Oliveira 24 February 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-04-17T22:47:12Z No. of bitstreams: 1 GabrielaLuchezeDeOliveiraLopes_TESE.pdf: 6049374 bytes, checksum: 3515f5da06487f76c77ce277db17c307 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-04-19T23:33:36Z (GMT) No. of bitstreams: 1 GabrielaLuchezeDeOliveiraLopes_TESE.pdf: 6049374 bytes, checksum: 3515f5da06487f76c77ce277db17c307 (MD5) / Made available in DSpace on 2017-04-19T23:33:36Z (GMT). No. of bitstreams: 1 GabrielaLuchezeDeOliveiraLopes_TESE.pdf: 6049374 bytes, checksum: 3515f5da06487f76c77ce277db17c307 (MD5) Previous issue date: 2017-02-24 / A pesquisa que originou este texto de tese de doutorado teve como objetivo examinar de que forma as ideias de John Wallis, emergentes na obra Arithmetica Infinitorum, datada de 1656, apresentou inova??es que podem contribuir para o encaminhamento conceitual e did?tico de no??es b?sicas da componente curricular de C?lculo Diferencial e Integral, no curso de Licenciatura em Matem?tica. Nesse sentido, avaliamos o potencial pedag?gico da referida obra para subsidiar o ensino de conceitos matem?ticos, em particular as no??es de integrais, com vistas ao melhoramento do entendimento dos estudantes acerca dessas ideias matem?ticas, tratadas nos Cursos de Forma??o de Professores de Matem?tica. Por admitirmos que os alunos necessitam ampliar o n?mero de trajet?rias que levam ao desenvolvimento de uma ideia Matem?tica ? que, neste trabalho, nos propusemos a responder a seguinte quest?o: como a explora??o did?tica do exerc?cio criativo de um matem?tico na hist?ria pode contribuir na abordagem pedag?gica para o ensino de conte?dos de C?lculo e An?lise na Licenciatura em Matem?tica? Para tal, apoiamo-nos em princ?pios de criatividade elaborados por Mihaly Csikszentmihalyi, que prop?s um modelo para criatividade que leva em considera??o o contexto social e cultural. Por considerarmos fundamental a explica??o do ciclo do pensamento referente ? inven??o matem?tica, associamos a esses princ?pios os processos do Pensamento Matem?tico Avan?ado, proposto por Tommy Dreyfus, de modo que destacamos como esses processos se conectam com as no??es de criatividade. Assim, formulamos um modelo para examinarmos a obra Arithmetica Infinitorum, indicando seus potenciais pedag?gicos para subsidiar o ensino de conceitos matem?ticos baseado em um car?ter investigativo. De maneira que foi poss?vel estabelecermos uma proposta de conex?o entre conhecimento matem?tico desenvolvido historicamente por diferentes matem?ticos e seus potenciais conceituais epistemol?gicos, com a possibilidade de ser implementada na a??o do professor de Matem?tica formador de professores de Matem?tica, com vistas a desenvolver compet?ncias e habilidades para uma futura atua??o do professor em forma??o. / The research which arose this doctorate?s thesis had as purpose examining in which ways John Wallis? ideas, emerging in Arithmetica Infinitorum, dated 1656, has presented contributing innovations for the didactic and conceptual guiding of Differential and Integral Calculus? curricular components basic notions, in Mathematics Licentiate course. For that matter, we evaluated the production?s pedagogical potential to subsidize mathematical concepts? teaching, mainly integral notions, aiming theim provement of students? understanding about these mathematical ideas, which are contemplated in the Mathematics Teachers training course. Acknowledging that the students need to expand the number of paths which lead to the development of a Mathematical idea, in this study we propose to answer the following question: how can the didactic exploration of a mathematician?s creative exercise contribute to the pedagogical approach for the Calculus and Analysis teaching, in Mathematics Licentiate course? For that we leaned on the creativity criteria discussed by Mihaly Csikszentmihalyi, due to considering it substantial in the thinking cycle explanation regarding the Mathematics creation. We relate to these principles the processes developed by Advanced Mathematical Thinking, suggested by Tommy Dreyfus, in order to highlight how these processes attach to creativity notions. Therefore, we formulated a model to examine the writing Arithmetica Infinitorum pointing its pedagogical potential to subsidize mathematical concepts? teaching, based on aninvestigative character. This way, it was possible to establish a connection proposal between mathematical knowledge historically developed by different mathematicians and their conceptual and epistemological potentials, with a possibility of being implemented in Mathematics teacher?s actions, Mathematics teacher?s trainer, in order to grow expertise and abilities for a forthcoming actuation of the training teacher.
39

Influência do ciclo hidrológico em pescarias comerciais na Amazônia Central, Brasil

Gonçalves, Vinícius Verona Carvalho, 92-99213-4998 23 April 2018 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-06-20T18:39:36Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_finalizada.pdf: 1987710 bytes, checksum: 46c6e0b1f07f99706e86684cdd0bd406 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-06-20T18:39:46Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_finalizada.pdf: 1987710 bytes, checksum: 46c6e0b1f07f99706e86684cdd0bd406 (MD5) / Made available in DSpace on 2018-06-20T18:39:47Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_finalizada.pdf: 1987710 bytes, checksum: 46c6e0b1f07f99706e86684cdd0bd406 (MD5) Previous issue date: 2018-04-23 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In the Central Amazon, the fisheries are artisanal in character, being practiced by fishermen in rivers and flooded areas. Thus, the main issue addressed in the study is to verify how the hydrological cycle influences the catches of species, considering that the landing is made up of species with different feeding strategies. Firstly, we carried out a previous characterization of the fisheries, in order to determine the main environments and species exploited, as well as, more productive and attractive periods for the fishing activity. We also list the fishing gear used by fishermen with the target species. The characterization indicated that the lake environments are more exploited by the fishermen, however, most of the catches come from the river channels. In relation to the composition of the landing, a total of 34 species were landed, being the jaraqui coarse scale (Semaprochilodus taenirus) and the jaraqui fine scale (Semaprochilodus insignis) the most exploited species. The period of flood presented a significant difference in the catch values per unit of effort (CPUE) when compared to the other hydrological periods. The fishing gear varied according to the environment where the fishing occurred and the species to be exploited. Later, we used generalized linear models (Covariance Analysis - ANCOVA) to determine the influence of the river level on the fisheries in the Lower Solimões River. The analysis of covariance for the flood period showed that all species were influenced by river level, and by fishing effort, there was still a positive interaction between fishing effort and detritus species. During the flood period, the fishing effort positively influenced all species, there was also a positive interaction between fishing effort, detritivorous and herbivorous species and a positive effort in river environments. In the ebb period, only the fishing effort was significant, with a negative interaction between the fishing environment and the effort. In the dry season, only the omnivorous species were influenced by the fishing effort and the level of the river, with negative interaction between fishing effort and omnivorous species. The results found may contribute to the generation of knowledge about fishing activities, providing information for the construction of public policies related to fisheries management in the state of Amazonas. / Na Amazônia Central as pescarias possuem caráter artesanal, sendo praticadas por pescadores em rios e áreas alagadas, sendo altamente influenciadas pela variação do nível do rio. Desse modo, a principal questão abordada no estudo é verificar como o ciclo hidrológico influencia nas capturas de espécies, considerando que o desembarque é constituído de espécies com diferentes estratégias alimentares. Primeiramente, realizamos uma caracterização prévia das pescarias, no intuito de determinar os principais ambientes e espécies explotados, bem como, períodos mais produtivos e atrativos para a atividade pesqueira. Também relacionamos os apetrechos de pesca utilizados pelos pescadores com as espécies alvo. A caracterização indicou que os ambientes de lago são mais explotados pelos pescadores, no entanto, a maior parte das capturas é oriunda dos canais de rios. Em relação à composição do desembarque, foram desembarcadas um total de 34 espécies, sendo o jaraqui escama grossa (Semaprochilodus taenirus) e o jaraqui escama fina (Semaprochilodus insignis) as espécies mais explotadas. O período de cheia apresentou valores positivos na captura por unidade de esforço (CPUE) quando comparado aos demais períodos hidrológicos. As artes de pesca variaram de acordo com o ambiente onde ocorreu a pesca e as espécies a serem explotadas. Posteriormente, utilizamos modelos lineares generalizados (Análise de covariância – ANCOVA) para determinar a influencia do nível do rio sobre as pescarias no Baixo Rio Solimões. A análise de covariância para o período de enchente mostrou que todas as espécies foram influenciadas pelo nível do rio, e pelo esforço de pesca, houve ainda uma interação positiva entre o esforço de pesca e espécies detritívoras. No período de cheia, o esforço de pesca influenciou positivamente todas as espécies, houve ainda uma interação positiva entre o esforço de pesca, espécies detritívoras e herbívoras e um esforço positivo nos ambientes de rio. No período de vazante, apenas o esforço de pesca foi significativo, com uma interação negativa entre o ambiente de pesca e o esforço. No período de seca, apenas as espécies onívoras foram influenciadas pelo esforço de pesca e o nível do rio, com interação negativa entre o esforço de pesca e espécies onívoras. Os resultados encontrados contribuem para a geração de conhecimento sobre atividades de pesca, fornecendo informações para a construção de políticas públicas relacionadas à gestão da pesca no estado do Amazonas.
40

Two-phase flow experiments in a model of the hot leg of a pressurised water reactor

Seidel, Tobias, Vallée, Christoph, Lucas, Dirk, Beyer, Matthias, Deen, Darlianto January 2010 (has links)
In order to investigate the two-phase flow behaviour in a complex reactor-typical geometry and to supply suitable data for CFD code validation, a model of the hot leg of a pressurised water reactor was built at FZD. The hot leg model is operated in the pressure chamber of the TOPFLOW test facility, which is used to perform high-pressure experiments under pressure equilibrium with the inside atmosphere of the chamber. This technique makes it possible to visualise the two-phase flow through large windows, also at reactor-typical pressure levels. In order to optimise the optical observation possibilities, the test section was designed with a rectangular cross-section. Experiments were performed with air and water at 1.5 and 3.0 bar at room temperature as well as with steam and water at 15, 30 and 50 bar and the corresponding saturation temperature (i.e. up to 264°C). The total of 194 runs are divided into 4 types of experiments covering stationary co-current flow, counter-current flow, flow without water circulation and transient counter-current flow limitation (CCFL) experiments. This report provides a detailed documentation of the experiments including information on the experimental setup, experimental procedure, test matrix and on the calibration of the measuring devices. The available data is described and data sheets were arranged for each experiment in order to give an overview of the most important parameters. For the cocurrent flow experiments, water level histograms were arranged and used to characterise the flow in the hot leg. In fact, the form of the probability distribution was found to be sensitive to the boundary conditions and, therefore, is useful for the CFD comparison. Furthermore, the flooding characteristics of the hot leg model plotted in terms of the classical Wallis parameter or Kutateladze number were found to fail to properly correlate the data of the air/water and steam/water series. Therefore, a modified Wallis parameter is proposed, which takes the effect of viscosity into account.

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