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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.
71

Fotobiomodulação comparativa entre o laser e LED de baixa intensidade na angiogênese de feridas cutâneas de ratos / Comparative fotobiomodulation between the LED and low intensity laser in the angiogenisis of skin wounds in rats

Corazza, Adalberto Vieira 12 December 2005 (has links)
Os diodos emissores de luz – Light Emitting Diodes – (LEDs) são uma fonte de luz que estão sendo introduzidas comercialmente, mas com discreta base científica nesta modalidade fototerapêutica. O presente estudo comparou os efeitos angiogênicos da luz laser coerente e colimada à luz LED ausente de coerência e colimação em feridas induzidas em ratos, com fluências diferentes. O modelo experimental consistia da indução de uma ferida circular no quadríceps de 120 ratos, utilizando um “punch" com 15 mm de diâmetro. Os animais foram divididos aleatoriamente em 5 grupos: laser (660 nm) e LED (635 nm), sendo cada um ajustado a 5 J/'CM POT.2' e 20 J/'CM POT.2', além do controle. Após 6 horas da indução das feridas, os grupos tratados recebiam aplicação pontual de contato, e irradiados a cada 24 horas. A angiogênese foi analisada por meio da histomorfometria (H.E), e a contração das feridas pelo software de planimetria, sendo estudados os resultados no 3º, 7º, 14º e 21º dias pós-lesão. Os achados da análise histológica no 3º dia foram determinantes para induzir uma grande eficiência na proliferação de vasos sanguíneos dos grupos tratados em relação ao controle, demonstrando uma taxa próxima da constante no 7º dia, e com discreto aumento no 14º dia, porém com destaque para a tecnologia LED a 5 J/'CM POT.2' (p '< OU =' 0,05). No 21º dia, os grupos fototratados com fluência de 5 J/'CM POT.2' apresentavam valores estatísticos com maior eficiência na angiogênese quando comparados com o grupo laser a 20 J/'CM POT.2, sugerindo que fluências elevadas podem induzir um processo do tipo saturação. Não ocorreu diferença da neovascularização no centro e nas margens da ferida (p '< OU =' 0,05), sugerindo que ocorria uma fotobiomodulação de toda a lesão, favorecendo o crescimento homogêneo dos vasos sanguíneos. Tanto o laser quanto o LED não apresentaram resultados significativos na redução da área das feridas. As fototerapias a laser e LED de baixa intensidade sugeriram que a coerência e a colimação não eram fatores decisivos para induzir alterações nas funções celulares, e sim a banda de absorção do espectro eletromagnético. Ambas as fontes de luz vermelha ajustadas a fluências de 5 J/'CM POT.2' podem demonstrar resultados expressivos no estímulo angiogênico em pele lesada / The light emitting diodes (LEDs) are a source of light that have been commercially introduced, but still with a lack in its scientific basis in this phototherapeutic modality. The present study compared the angiogenics effects of the laser and LED illumination in induced wounds in rat, with fluencies different. The experimental model consisted of the induction of a circular wound on the quadriceps of 120 rats, using a “punch" with 15 mm diameter. Animals were divided randomyzed in 5 groups: laser and LED each device with a dosage of 5 J/'CM POT.2' and 20 J/'CM POT.2', and control. After 6 hours of the induction of the wounds, the treated groups received contact of punctual application, and irradiated every 24 hours. The angiogenesis was studied through the histomorphometric (H.E) and the wounds contraction was photographed and analyzed in the planimetrical software in the 3rd, 7th, 14th and 21st lesion induced days. The discoveries of the histological analysis in the 3rd day revealed larger efficiency in the proliferation of the blood vessels in all irradiated groups in comparison to controls, being a rate near of the constant in the 7th day, following to discreet improves in the 14th, even so with prominence for the LED with 5 J/'CM POT.2'. In the 21st day, the groups phototreatment with fluence of 5 J/'CM POT.2' showed similar statistically values in the larger efficiency in the angiogenesis, when to compare to laser with 20 J/'CM POT.2', suggesting high fluencies can induced a saturation process. The average of the area reduction of the wound didn't present similar statistician values of the treated groups in relation to the control (p '< OU =' 0,05). The phototherapeutic laser and LEDs of low intensity they suggested that the coherence and the collimation were not decisive factors to induce alterations in the cellular functions, but the band of the spectrum electromagnetic. The both red source of light agreements to fluencies of the 5 J/'CM POT.2', they can demonstrate expressive results in the incentive ulcerated skin angiogenic
72

Análise do padrão IEEE 802.11g para a comunicação do sistema de controle distribuído de semáforos. / IEEE 802.11g standart analysis for communication of the distributed control system of traffic lights.

Miguel, Danilo de Souza 16 June 2015 (has links)
Este trabalho propõe a análise da comunicação sem fio para um sistema de controle distribuído de semáforos, a partir da revisão das literaturas, realização de simulações e experimentos, os quais consideram as especificações estabelecidas para o sistema de semáforos. As simulações e os experimentos se baseiam na avaliação do comportamento da comunicação perante a alteração de alguns parâmetros de configuração da rede. O estudo apresentado envolve análises relacionadas ao padrão IEEE 802.11g e às definições da camada física apresentadas nas especificações do padrão. Os métodos utilizados envolvem o estudo e experimentação de parâmetros relacionados à potência de transmissão e recepção, além de análise dos esquemas de modulação utilizados pelo padrão IEEE 802.11g. A metodologia aplicada a este trabalho envolve o conhecimento das características e capacidade dos esquemas de modulação responsáveis pela definição das taxas de transmissão. As análises mostram que a possibilidade de adequação dos parâmetros de configuração de rede, levando em consideração o cenário de aplicação, pode ser um fator essencial para o bom desempenho de todo o sistema. / This work proposes the analysis of wireless communication for a distributed control system of traffic lights, from the review of the literature and conducting simulations and experiments, which consider the specifications established for traffic light system. The simulations and experiments are based on the evaluation of the communication behavior towards changing some network configuration parameters. The study presented involves analysis related to the IEEE 802.11g standard and definitions of the physical layer shown in standard specifications. The methods used involve the study and testing of parameters related to power transmission and reception, and analysis of modulation schemes used by the IEEE 802.11g standard. The methodology applied to this work involves the knowledge of the characteristics and capacity of modulation schemes responsible for setting transmission rates. The analyses show that the possibility of adaptation network configuration parameters considering the application scenario may be an essential factor to the performance of the entire system.
73

CICATRIZES ABERTAS PELOS RISCOS RODRIGUEANOS.

Aguiar, Daura Maria Guimarães 03 December 2013 (has links)
Made available in DSpace on 2016-08-10T11:07:13Z (GMT). No. of bitstreams: 1 DAURA MARIA GUIMARAES AGUIAR.pdf: 1153241 bytes, checksum: d9ba967a6b63ae403a7d9451aa7aba89 (MD5) Previous issue date: 2013-12-03 / This paper conducts a study of the work Cicatrizes do Risco ou Crepúsculo das Luzes, by Cida Rodrigues , published in 2001, dealing with themes that relate to the fragmentation of human being in time and space, his reminiscences of childhood and distressing obsession with writing. The act of writing is a kind of exorcism of what will be inside this moment that speaks for itself, through the first person of the verb and, sometimes, is shown by an omniscient narrator, capable of stripping the most covert thoughts of this character not shown in full and not allowed to touch. Other times, shown by the lyrical voice of the fragments that make up the "Moments " (chapters) that make up the work, the corpus of this work. This dissertation also is an attempt to reveal the estrangement caused at the outset, the "Moments" that open each part of the work under study, as well as a typical writing postmodernity, marked by the mixture of literary genres moving freely between prose and poetry, and these are presented in many different ways, making the result of the trial set of literary writing. / O presente trabalho realiza um estudo da obra Cicatrizes do Risco ou Crepúsculo das Luzes, de Cida Rodrigues, publicada em 2001, tratando de temas que se relacionam à fragmentação do ser no tempo e no espaço, suas reminiscências da infância e a angustiante obsessão pela escrita. O ato de escrever representa uma espécie de exorcismo do que vai por dentro deste ser que ora fala por si mesma, através da primeira pessoa do verbo e, ora, é mostrada por um narrador onisciente, capaz de desnudar os mais encobertos pensamentos desta personagem que não se mostra por inteiro e não se deixa tocar. Outras vezes, revela-se pela voz do eu lírico nos fragmentos que compõem os Instantes (capítulos) que constituem a obra, corpus deste trabalho. Esta dissertação é, ainda, uma tentativa de revelar o estranhamento provocado, logo de início, pelos Instantes que abrem cada parte da obra em estudo, bem como por uma escrita típica da pós-modernidade, marcada pela mistura de gêneros literários transitando livremente entre a prosa e a poesia, sendo que estas se apresentam das mais variadas formas, fazendo configurar o resultado da experimentação da escrita literária.
74

EFEITOS DA LUZ DE UM FOTOPOLIMERIZADOR LED NA TEMPERATURA PULPAR BASAL IN VIVO EM PRÉ-MOLARES HUMANOS E SUA CORRELAÇÃO COM AS CARACTERÍSTICAS ANATÔMICAS DENTAIS EX VIVO / Effects of ligth emitted by a LED light curing unit on the in vivo baseline pulp temperature of intact human premolars and their correlation within ex vivo dental anatomic caracteristics

Runnacles, Patricio 17 December 2014 (has links)
Made available in DSpace on 2017-07-24T19:21:57Z (GMT). No. of bitstreams: 1 Patricio Runnacles.pdf: 1899405 bytes, checksum: f12074a5a86f43aa25ef7c17d1ba8e87 (MD5) Previous issue date: 2014-12-17 / Objective: This in vivo study evaluated the baseline pulp temperature in human intact upper premolars and the pulp temperature rise induced by light emitted by a high power polywave Light Emitting Diode (LED) light curing unit (LCU); also, the possible correlation between the change in temperature (ΔT) and the volume of the crown and the pulp chamber ex vivo. Material and methods: after approval of the local Ethics Committee was obtained (protocol #255,945), upper right and left first premolars requiring extraction for orthodontic reasons from 8 volunteers (n=15) received infiltrative and intraligamental anesthesia and were isolated using rubber dam. A small, occlusal preparation was made using high-speed hand piece, under constant air-water spray, until a minute pulp exposure was attained. The sterile probe from a wireless, NIST-traceable, temperature acquisition system (Temperature Data Acquisition - Thermes WFI, Physitemp) was inserted directly into the coronal pulp. Once the baseline pulp temperature was stable, the buccal surface was exposed to polywave light from a LED LCU (Bluephase 20i, Ivoclar Vivadent) using selected EMs: 10-s either in low (10-s/L) or High (10-s/H); 5-s-Turbo (5-s/T); and 60-s-High (60-s/H) intensities, allowing a 7-min span between each exposure. Peak PT values and PT increases from baseline (ΔT) after exposure were subjected to 1-Way, repeated measures ANOVAs, and Bonferroni's post-hoc tests (α=0.05). Linear regression analysis was performed to establish the relationship between applied radiant exposure and ΔT. Linear regression analysis was performed to establish the relationship between applied radiant exposure and ΔT. the teeth were extracted according to treatment plan. The crown and pulp volumes were measured using micro-tomography scanner, and pulp chamber / crown volume ratio was determined. Afterwards, premolar buccal-lingual, cervico-occlusal, mesio-distal dimensions as well as between cusp distances were measured using a digital caliper. Results: consistent temperature below body temperature, resulting in an average core temperature of 35 ° C (+ 0.7 ° C) was found. All modes of activation of the LED promoted significant temperature rise in the pulp chamber. A positive correlation between energy density and thermal variation was observed. No correlation was observed between coronal volume, the pulp chamber with temperature changes. A significant negative correlation was noted between pulp temperature changes when 10-s/L was used and VL. / Objetivo: Este estudo in vivo avaliou a temperatura basal da polpa em pré-molares hígidos superiores em humanos e o aumento da temperatura induzida pela luz emitida por um fotopolimerizador à base de Diodo Emissor de Luz (LED) polywave de alta potência; além disso, a possível correlação entre a variação de temperatura (ΔT) e o volume da coroa e da câmara pulpar ex vivo. Material e métodos: após aprovação da Comissão de Ética da Universidade Estadual de Ponta Grossa (UEPG) (protocolo #255,945), pré-molares direito e esquerdo de 8 pacientes voluntários (n=15), que necessitavam de extrações por motivos ortodônticos, receberam anestesia infiltrativa e intraligamentar e isolamento absoluto. Um pequeno acesso oclusal com exposição pulpar foi realizado usando alta-rotação, sob spray de ar e água constante, até atingir uma mínima exposição da polpa. Inseriu-se uma sonda estéril de um termopar wireless (Temperature Data Acquisition - Thermes WFI, Physitemp) diretamente no interior da câmara pulpar. Após a estabilização da temperatura basal da polpa, a face vestibular foi exposta à luz de um fotopolimerizador LED polywave (Bluephase 20i, Ivoclar Vivadent), usando modos de exposição selecionados: 10s em baixa potência (10s/L), 10s em alta potência (10s/H), 5s em potência turbo (5s/T) e 60s em alta potência (60s/H), respeitando um intervalo de 7 min entre cada exposição. A temperatura pulpar foi registrada a cada 0,2 s. Os valores absolutos e a variação da temperatura pulpar após exposição foram submetidos a análise estatística fator único (ANOVA) com medidas repetidas seguida pelo teste de Bonferroni (α=0,05). A correlação entre as densidades de energia aplicadas e os valores das variações de aumento de temperatura foi estabelecida por uma análise de regressão linear. Após as exodontias realizadas de acordo com os planos de tratamento, os elementos dentários (n=11) foram armazenados em Timol 0,1% e as dimensões mésio-distal da face oclusal (MD), cérvico-oclusal (CO), e vestíbulo-lingual (VL) da coroa dos dentes foram medidas com um paquímetro digital. Os volumes coronário e da câmara pulpar foram determinados por meio de microtomografia computadorizada (μCT) dos espécimes. Resultados: foi encontrada uma temperatura basal média consistente abaixo da temperatura corporal, de 35°C (+ 0,7°C). Todos os modos de ativação do LED promoveram aumento significativo de temperatura na câmara pulpar. Foi observada uma correlação positiva entre densidade de energia e variação térmica. Não houve correlação dos volumes coronal e da câmara pulpar com as variações térmicas, mas foi encontrada uma correlação negativa entre a medida VL das coroas e o ΔT no modo de exposição 10s/L.
75

Impact of lighting conditions on the developmental physiology of Atlantic salmon (Salmo salar)

Clokie, Benjamin Gregory James January 2017 (has links)
The Atlantic salmon (Salmo salar) lifecycle is punctuated by distinct ontogenic stages which are routinely manipulated commercially by photoperiod regimes to enable year-round production. As such, light plays a critical role throughout the production cycle, however, it remains poorly characterised and light spectrum and intensity have not been defined optimally yet. This thesis was therefore set out to test the effects of narrow bandwidth light (Blue-&lambda;(max) 444 nm, Green-&lambda;(max) 523 nm, Red-&lambda;(max) 632 nm and White) and intensity in freshwater (FW). Fry-parr development, out-of-season smoltification and ocular and vertebral health were examined as was the long-term effects of FW light regimes on seawater (SW) growth and muscle structure. In addition, the impact of photoperiod regimes on out-of-season smolts following transfer to SW was investigated. &NewLine; Major findings from the trials conducted show that light spectrum and intensity influence parr development with lower intensities performing better than higher intensities. Both the initiation and duration of smoltification was impacted by spectrum. Importantly, this doctoral work showed that daily changes in light intensity, from low during the scotophase to high during the photophase applied for the duration of a standard out-of-season smoltification regime was capable of providing a sufficient cue for the induction of smoltification. Historic FW light exposure impacted SW performance and post-transfer SW photoperiod had significant impact upon growth and maturation development. Results based on changes to the gonadosomatic index provide important guidance for suitable post-transfer photoperiods for smolt transferred to SW around the winter solstice. Importantly, from the parameters tested, exposure to different spectrum or light intensities did not adversely affect vertebral or ocular health. &NewLine; This thesis did not only focus on the physiological effects of light but also aimed to characterise better the pathways involved in light perception and integration. To do so, the neural response to both broad spectrum white light, darkness and Red and Blue light was investigated through deep brain insitu-hybridisation and high throughput sequencing (NGS) of the pituitary gland. Results showed substantial spectral and light/dark changes in the both the deep brain and pituitary transcriptome. Overall, this research provides both scientifically interesting and commercially relevant guidance for the optimisation of lighting systems for use in captive salmon aquaculture. Major findings from the trials conducted show that light spectrum and intensity influence parr development with lower intensities performing better than higher intensities. Both the initiation and duration of smoltification was impacted by spectrum. Importantly, this doctoral work showed that daily changes in light intensity, from low during the scotophase to high during the photophase applied for the duration of a standard out-of-season smoltification regime was capable of providing a sufficient cue for the induction of smoltification. Historic FW light exposure impacted SW performance and post-transfer SW photoperiod had significant impact upon growth and maturation development. Results based on changes to the gonadosomatic index provide important guidance for suitable post-transfer photoperiods for smolt transferred to SW around the winter solstice. Importantly, from the parameters tested, exposure to different spectrum or light intensities did not adversely affect vertebral or ocular health. This thesis did not only focus on the physiological effects of light but also aimed to characterise better the pathways involved in light perception and integration. To do so, the neural response to both broad spectrum white light, darkness and Red and Blue light was investigated through deep brain insitu-hybridisation and high throughput sequencing (NGS) of the pituitary gland. Results showed substantial spectral and light/ dark changes in the both the deep brain and pituitary transcriptome. Overall, this research provides both scientifically interesting and commercially relevant guidance for the optimisation of lighting systems for use in captive salmon aquaculture.
76

Influência dos métodos de fotoativação e fontes de luz nas propriedades de diferentes resinas compostas

Costa, Simone Xavier Silva [UNESP] 19 March 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-19Bitstream added on 2014-06-13T18:41:40Z : No. of bitstreams: 1 costa_sxs_dr_arafo.pdf: 852844 bytes, checksum: 8945fe6817e7f7f0051c98cb920416e1 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo deste trabalho, dividido em três estudos, foi avaliar: (1) a influência da utilização de diferentes fontes de luz e métodos de fotoativação sobre o grau de conversão e a contração de polimerização de uma resina composta nanoparticulada; (2) a influência da utilização dos diferentes métodos de fotoativacao, disponibilizados por aparelhos LED de 2a geração, sobre a contração volumétrica das resinas compostas microhíbrida e nanopartículada e (3) as propriedades térmicas e o grau de conversão das resinas compostas microhíbrida e nanopartículada, submetidas aos diferentes métodos de fotoativação disponibilizados por aparelhos LED de 2a geracao. No primeiro estudo, o grau de conversão (GC) foi avaliado pelo metodo da espectroscopia infravermelha transformada de Fourier (FT-IR) e as forças de contração (C) mensuradas em máquina de ensaios universal (EMIC). Os dados obtidos para o GC e C foram analísados estatísticamente pelo teste da análise de variancia (ANOVA), sendo que para as forças de contração, a correção de Welch e o teste Tamhane também foram empregados. No segundo estudo, a contração volumétrica foi avaliada por um mecanismo de vídeo e imagem (AcuvolR/Bisco) e os dados obtidos foram análisados estatísticamente pelos testes ANOVA e Tukey. No terceiro estudo, o método da calorimetria exploratória diferencial foi empregado para avaliar a temperatura de transição vitrea (Tg) e de degradação dos materiais e o GC por FTIR. Os dados relativos ao GC foram análisados estatísticamente pelos testes ANOVA e Tukey. Os resultados demonstraram diferenças na contração de polimerização de acordo com o método de fotoativação empregado. No primeiro e segundo estudos, mesmo empregando diferentes metodologias, o método de fotoativação contínuo apresentou os maiores valores de contração. Por outro lado,o GC não... / The aim of this work, divided into three studies, was evaluate: (1) the influence of different light sources and photo-activation methods on degree of conversion and polymerization shrinkage of a nanocomposite resin; (2) the influence of different photo-activation methods, available by the 2nd generation LED light-curing units, on the volumetric shrinkage of microhybrid and nanocomposite resins and (3) thermal properties and degree of conversion of microhybrid and nanocomposite resins submitted to different photo-activation methods available by 2nd generation LED light-curing units. In the first study, degree of conversion (DC) was evaluated by Fourier transform infrared spectroscopy (FT-IR) and shrinkage forces (S) were measured in a universal testing machine (EMIC). The data obtained for DC and S were analyzed by Analysis of Variance test (ANOVA) and for S Welch’s correction and Tamhane’s tests were also employed. In the second study, volumetric shrinkage was evaluated by video-imaging device (AcuvolR/Bisco) and data were analyzed by ANOVA and Tukey’s test. In the third study, differential scanning calorimetry was used in order to observe glass transition temperature (Tg) and degradation peak of the materials and DC was evaluated for FT-IR. The DC data were analyzed by ANOVA and Tukey’s test. The results showed differences in the polymerization shrinkage according to photo-activation method employed. In the first and second studies, the continuous photo-activation methods presented the highest values for shrinkage even though different methodologies were used to assess. Moreover, DC was not influenced by the photo-activation method but was influenced by light sources. The lowest DC values were observed for halogen light-curing unit. In the second study beyond the influence of the photo-activation... (Complete abstract click electronic access below)
77

Análise do padrão IEEE 802.11g para a comunicação do sistema de controle distribuído de semáforos. / IEEE 802.11g standart analysis for communication of the distributed control system of traffic lights.

Danilo de Souza Miguel 16 June 2015 (has links)
Este trabalho propõe a análise da comunicação sem fio para um sistema de controle distribuído de semáforos, a partir da revisão das literaturas, realização de simulações e experimentos, os quais consideram as especificações estabelecidas para o sistema de semáforos. As simulações e os experimentos se baseiam na avaliação do comportamento da comunicação perante a alteração de alguns parâmetros de configuração da rede. O estudo apresentado envolve análises relacionadas ao padrão IEEE 802.11g e às definições da camada física apresentadas nas especificações do padrão. Os métodos utilizados envolvem o estudo e experimentação de parâmetros relacionados à potência de transmissão e recepção, além de análise dos esquemas de modulação utilizados pelo padrão IEEE 802.11g. A metodologia aplicada a este trabalho envolve o conhecimento das características e capacidade dos esquemas de modulação responsáveis pela definição das taxas de transmissão. As análises mostram que a possibilidade de adequação dos parâmetros de configuração de rede, levando em consideração o cenário de aplicação, pode ser um fator essencial para o bom desempenho de todo o sistema. / This work proposes the analysis of wireless communication for a distributed control system of traffic lights, from the review of the literature and conducting simulations and experiments, which consider the specifications established for traffic light system. The simulations and experiments are based on the evaluation of the communication behavior towards changing some network configuration parameters. The study presented involves analysis related to the IEEE 802.11g standard and definitions of the physical layer shown in standard specifications. The methods used involve the study and testing of parameters related to power transmission and reception, and analysis of modulation schemes used by the IEEE 802.11g standard. The methodology applied to this work involves the knowledge of the characteristics and capacity of modulation schemes responsible for setting transmission rates. The analyses show that the possibility of adaptation network configuration parameters considering the application scenario may be an essential factor to the performance of the entire system.
78

Tryggheten på Brynäs - en uppföljning av Gävle kommuns trygghetsvandring

Forslund, Ida January 2010 (has links)
Studien var en uppföljning av en trygghetsvandring i stadsdelen Brynäs i Gävle som gjordes 2008 med medverkan av boende i stadsdelen och tjänstemän från kommunen. Syftet med denna undersökning var att ta reda på hur de boende uppfattar trygghet i stadsmiljö utifrån sig själva och med avseende på vissa i förväg formulerade punkter. Syftet var också att utvärdera hur boende i stadsdelen Brynäs uppfattar tryggheten i området efter de förändringar som Gävle kommun gjort i den byggda miljön. Resultaten visade att det viktigaste för tryggheten var generellt att ha kontroll på och överblick över vad som händer runtomkring en. Denna känsla kunde minska eller öka genom olika faktorer i den byggda miljön. Med tanke på detta kändes öppna platser tryggare än trånga och belysning ökade tryggheten till viss del. Det var också viktigt är att området kändes välskött och att det fanns mycket folk runtomkring en. Trafiksituationen på Brynäs uppfattades som väldigt otrygg. Angående oskötta miljöer kom diskussionerna ofta in på socialt utsatta miljöer och människor i sådana miljöer, som upplevdes som brottsbenägna. Människor som vistades i stadsmiljö var minst lika viktiga som miljöerna – miljöerna var ett medel för att dölja eller avslöja dessa människor.Resultaten visade också att informanterna till största delen inte märkt de förändringar som Gävle kommun genomfört. / This study was a follow up on a project on satefy in Brynäs, performed by the community of Gävle. The aim of the study was to investigate the perceptions of safety in Brynäs by the people living there, from the persons´ spontaneous points of view and from certain subjects already specified from present research. The aim of the study was also to examine how people on Brynäs percieve some interventions in the built urban environment in Brynäs that the community of Gävle made between 2008 and 2010. The results showed that the most important factors that make the environment feel safe was that it should give people an overview of the surroundings. The informants said that overview of the surroundings made them feel in control of what happens around them. The informants thought a lot about areas with low socioeconomic status and the people living there as correlated with increaesed risks of crime. The people appearing in urban environments were as important for the perceptions of safety as the environments themselves – the environment could hide or show people able to comitting crimes to other people. The informants had mostly not noticed the interventions in the built environment made by the community of Gävle.
79

Transboundary water resource management of the Pongolo River/Rio Maputo.

Tompkins, Robyn. January 2002 (has links)
In the Twenty-first Century, sustainable water management is likely to be humanity's greatest challenge in a world of ever-increasing demand. Legal instruments both international and national regulate and provide a general framework for the use and management of international waters. Future basin management agreements can be informed by examining the degree of success, in terms of sustainability and equity, achieved by such agreements. That success can be influenced by the degree to which such agreements support the human right to water implicitly stated in international customary law, through a collaborative management approach. Since 1988, attempts by communities on the Pongolo floodplain to be involved in Pongolopoort Dam releases, have met with little success. Recently, the Department of Water Affairs and Forestry has begun to support those efforts, but the approach remains a sectoral one, and is primarily concerned with water issues. The South African National Water Act 36 of 1998 provides for environmental management and public participation, as well as providing explicitly for the rights of individual water users, but its implementation is hampered by an overwhelming emphasis on technical considerations and a lack of political will to embrace collaborative management systems. Little effort is expended on collaborative management methods, though the level of transparency in water management is improving, despite remaining highly centralised. The level and extent of incentives for local community participation is low, and systematic monitoring is in its early development. International river basin agreements generally take a top-down or state-driven approach, though there are some examples where local cross-border communities have participated successfully in the implementation of international agreements and management of transboundary basins. South Africa, Swaziland and M09ambique signed the Interim Incomaputo Agreement, which includes the Maputo basin, in August 2002. Once again, the approach to this agreement has been highly sectoral in that negotiations were handled entirely by water officials in the relevant countries. A lack of transparency has prevailed in the negotiation stages, though through the basin studies, which will inform implementation plans, the level of participation should improve. There is overwhelming consensus that integrated management is the key to sustainable international river basin management. Formal and systematic methods for inter-departmental communication, both nationally and internationally are currently not being implemented, which has significant negative impacts on integrated management. Research in this area represents an opportunity to explore collaborative management of an international river basin in an area that is, as yet, unstressed in terms of population and water supply. / Thesis (M.Env.Dev.)-University of Natal, Pietermaritzburg, 2002.
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多期數之信用風險違約機率驗證法 / The Calibration Method of Probability of Default under Multiple Periods

林福文, Lin, Fu-Wen Unknown Date (has links)
新巴賽爾資協定中,針對銀行風險管理具備三大支柱,支柱一管理信用風險、市場風險及作業風險,其中信用風險方法更分為標準法、基礎內部模型法與進階內部模型法。不論銀行採用何種內部模型法,銀行必須有估計違約機率之能力,並且送交監理機關審查核准。為了確保預測違約機率之適當,巴賽爾銀行監理委員會BCBS (2005) 對於不同資料長度與驗證期間分別建議二項檢定、卡方檢定、常態檢定與紅綠燈檢定。當資料期數足夠時,BCBS推薦使用紅綠燈檢定,但該檢定需要若干假設:違約事件間相互獨立且違約事件在時間上亦獨立,因此在BCBS (2005) 中之某些情境下,採用紅綠燈檢定驗證違約機率會受到違約事件之間並非獨立,造成中央極限定理不適當地近似標準化之違約機率至常態分配,且模擬之型一誤差亦有高估之結果。 在違約事件之間獨立且無時間相關性下,本文建議採用卜瓦松分配近似二項分配;在違約事件之間非獨立且具有時間相關性下,本文則建議採用二項分配,結合granularity adjustment,使違約事件間之相關性可以反映在不同顏色之分色點上。最後,由數量模擬結果顯示:本文建議採用之改良方法,皆可有效將型一誤差維持在設定之顯著水準上,並反映真實之檢定力。因此,不論對銀行或監理機關來說,改良之違約機率驗證方法係值得使用之方法。 / There are three methods in Basel II (Standardized Approach, Foundation IRB Approach and Advanced IRB Approach) to calculate the capital charges. The banks have to estimate probability of default (PD) if they use IRB approach. Four statistic methods recommended by BCBS worthy to validate the PD: Binomial test, Chi-square test, Normal test and Extended Traffic Lights test (ETLT). If the data are long enough, BCBS recommended using the ETLT with the assumptions that the obligors are independent and also independent in time. From numerical results, validating PDs by ETLT will overestimate the type I errors and statistic power. We suggest two methods in different scenarios to make the type I errors closed to the significant level. First, we suggest to approximate Normal distribution in Poisson distribution with randomization technique. Second, we combine Binomial distribution with granularity adjustment to fit the correlation between the obligors. Both methods not only perform well in type I errors, but also reflect the real statistic power. For the banks, both methods are worthy to use for avoiding to increasing the capital charges unexpectedly or the operational risk of the banks.

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