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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.
51

Damping-off and stem rot of cowpea in Benin caused by Sclerotium Rolfsii

Adandonon, Appolinaire 14 January 2005 (has links)
The damping-off and stem rot disease syndrome is harmful to many cultivated crops. Damping-off and stem rot caused by Sclerotium rolfsii Sacc. on cowpea results in yield losses with serious socio-economic implications. The objectives of the present study were to investigate the occurrence of the diseases in Benin, study etiology and factors influencing the diseases, and develop strategies for the control of the diseases in the field. Results showed that the diseases are distributed countrywide. Sclerotium rolfsii was the main causal agent but minor pathogens, namely Pythium sp., Rhizoctonia solani Kühn and Phoma pomorum Thüm were also recorded. In the Ouémé valley, the diseases were favoured by soil moisture and S. rolfsii initial inoculum that were higher closer to the river. Sclerotium rolfsii isolates collected in the valley showed genetic diversity in terms of pathogenicity, mycelial compatibility groups and ITS rDNA sequences. A paper-based screening method was found to be a rapid laboratory method for screening for resistance in cowpea cultivars. Furtheremore, Moringa oleifera L. leaf extracts, Trichoderma Kd 63 and Trichoderma IITA 508 significantly reduced the disease incidence. The best disease control was recorded in the field when M. oleifera seed treatment was integrated with a soil sprinkle of Trichoderma. The present work provides information on damping-off and stem rot of cowpea in Benin and control strategies for ecologically sustainable cowpea production. / Thesis (DPhil (Microbiology and Plant Pathology))--University of Pretoria, 2006. / Microbiology and Plant Pathology / unrestricted
52

Mecanismos de interação do carrapato Rhipicephalus microplus com o fungo acaropatogênico Metarhizium anisopliae

Araujo, Anelise Webster de Moura Vieira January 2017 (has links)
O carrapato Rhipicephalus microplus é o principal ectoparasita de bovinos. O controle de R. microplus baseia-se principalmente no uso de acaricidas químicos, o que contribuiu para o problema emergente da seleção de populações de carrapatos resistentes. Portanto, há a necessidade do desenvolvimento de métodos mais eficientes/sustentáveis de controle, como o controle biológico utilizando fungos acaropatogênicos. A eficácia do fungo Metarhizium anisopliae de forma isolada ou em associação com acaricida químico para controle do carrapato bovino já foi evidenciada em condições de campo utilizando uma cepa de carrapatos resistente à acaricidas. No entanto, pouco se sabe sobre os mecanismos moleculares de R. microplus envolvidos na sua interação com M. anisopliae e com acaricidas. Assim, o objetivo do presente estudo foi avaliar a resposta de larvas de R. microplus expostas ao fungo, ao acaricida e à associação de ambos. Primeiramente foi realizado um estudo para determinar a metodologia mais indicada para avaliar o efeito in vitro do fungo M. anisopliae sobre larvas de R. microplus. Para isso, comparamos o Teste de Pacote de Larvas modificado (TPL) e o Teste de Imersão de Larvas (TIL). Os valores de tempo letal mediano (TL50) obtido na maior concentração de M. anisopliae (108conídios/mL) foram 24,8 e 9,2 dias para o TPL e TIL, respectivamente. A mortalidade após 21 dias foi de 38% e 98% para o TPL e TIL respectivamente, na mesma concentração. O TIL demonstrou ser o teste mais indicado a ser utilizado, sendo, portanto, escolhido para realização dos experimentos futuros. Em seguida foi realizado um estudo para comparar a suscetibilidade de diferentes isolados de R. microplus ao fungo M. anisopliae. Foram avaliados 67 isolados de campo. Para tanto, as larvas de R. microplus foram imersas em uma suspensão de M. anisopliae (108conídios/mL) durante 5 min. Os tempos letais medianos (TL50) variaram de 2,6 a 24,9 dias A mortalidade observada no 15º dia após o tratamento variou de 26,3 a 100% nas amostras testadas. Esses resultados demonstraram que as populações de campo de R. microplus apresentam uma alta variação em sua suscetibilidade a M. anisopliae. Por fim, foi realizada uma análise transcricional (RNAseq) de larvas de R. microplus expostas a M. anisopliae, cipermetrina, associação de ambos e do controle (não-tratado). A análise dos transcritos dos quatro grupos gerou um total de 507.792 sequências com um tamanho total de 303.160.891 pb. Foram encontrados 31 genes diferencialmente expressos no grupo controle quando comparado com M. anisopliae, 39 com cipermetrina e 73 com M. anisopliae + cipermetrina. M. anisopliae e o grupo da associação apresentaram 81 genes diferencialmente expressos e M. anisopliae e cipermetrina, 46. Houve 177 genes diferencialmente expressos ao comparar M. anisopliae + cipermetrina com larvas expostas à cipermetrina Os resultados deste estudo demonstraram que a associação M. anisopliae + cipermetrina aumentou a expressão de genes relacionados a resposta à agressão, provavelmente pelo fato da associação provocar uma agressão maior ao carrapato e este responder de forma mais rápida, levando à superexpressão de genes de defesa. As descobertas deste estudo fornecem informações sobre as vias e mecanismos moleculares de R. microplus ativados em resposta à interação de M. anisopliae e a acaricida. Além disso, esses estudos estabelecem as bases para pesquisas futuras sobre genes-chave que controlam a suscetibilidade de R. microplus a M. anisopliae. O sinergismo evidenciado em nossos estudos comprova a ideia de que o controle integrado, utilizando o controle biológico com o controle químico é uma opção tanto para o controle de cepas de carrapatos resistentes à acaricidas, quanto para um controle mais rápido de cepas de carrapatos que não apresentam resistência ou que apresentem resistência intermediária. / The tick Rhipicephalus microplus is the major cattle ectoparasite. The control of R. microplus is based mainly on the use of chemical acaricides, which contributed to the emerging problem of the selection of tick populations resistant to acaricides. Therefore, there is a need for the development of more efficient/sustainable methods of control, such as biological control using acari pathogenic fungi. The effectiveness of the fungus Metarhizium anisopliae alone or in association with chemical acaricide to control the bovine tick has already been evidenced under field conditions using an acaricide resistant tick strain. However, to date, little is known about the molecular pathways of R. microplus involved with its interaction with M. anisopliae and with acaricides. Thus, the aim of the present study is to evaluate the response of R. microplus larvae exposed to the fungus, the acaricide and the association of both. Firstly, a study was carried out to determine the most appropriate methodology to evaluate the in vitro effect of the fungus M. anisopliae on larvae of R. microplus tick. For this, we compared the Modified Larval Packet Test (LPT) and the Larval Immersion Test (LIT). The values of lethal time (LT50) obtained in the highest concentration of M. anisopliae (108conidia / mL) were 24.8 and 9.2 days for LPT and LIT, respectively. Mortality after 21 days was 38% and 98% for LPT and LIT, respectively, at the same concentration. The LIT proved to be the most indicated test to be used and was therefore chosen to carry out the following experiments Then, a study was performed to compare the susceptibility of different R. microplus isolates to M. anisopliae fungus. Sixty-seven field isolates were evaluated. For this, R. microplus larvae were immersed in a suspension of M. anisopliae (108conidia/mL) for 5 min. Lethal times (LT50) ranged from 2.6 to 24.9 days. Mortality observed on the 15th day after treatment ranged from 26.3 to 100% in the tested samples. These results demonstrated that R. microplus field populations showed a high variation in their susceptibility to M. anisopliae. Finally, a RNAseq analysis of R. microplus larvae exposed to M. anisopliae, cypermethrin, association of both or untreated (control) was performed. Analysis of the transcripts of the four groups generated a total of 507,792 sequences with a total length of 303,160,891 bp. We found 31 differentially expressed genes in the control group when compared to M. anisopliae, 39 with cypermethrin and 73 with M. anisopliae + cypermethrin. M. anisopliae and the association group had 81 differentially expressed genes and M. anisopliae and cypermethrin, 46 There were 177 differentially expressed genes when comparing M. anisopliae + cypermethrin with cypermethrin exposed larvae. The results of this study demonstrated that the association of M. anisopliae + cypermethrin increased the expression of genes related to response to aggression, possibly because the M. anisopliae + cypermethrin association causes a greater aggression to the tick and, then it could respond quickly, leading to overexpression of defense genes. The findings of this study provide information on the pathways and molecular mechanisms of R. microplus in response to the interaction of M. anisopliae and acaricides. In addition, these studies establish the basis for future research on key genes that control the susceptibility of R. microplus to M. anisopliae. The synergism evidenced in our studies confirms the idea that integrated control using biological control and chemical control is an option both for the control of acaricide resistant tick strains and for a faster control of tick strains that do not show resistance or exhibit intermediate resistance.
53

Integration of the herbicide 2, 4-D with the rosette weevil Trichosirocalus horridus (Panzer) for control of Carduus thistles

Stoyer, Tracy Lynne January 1985 (has links)
Master of Science
54

Análise dos facilitadores e das barreiras para integração e compartilhamento de informações de segurança pública: um estudo de caso no Centro de Comando e Controle do Rio Grande do Sul

Santos, Ivens Giuliano Campos dos 19 December 2018 (has links)
Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2019-03-22T13:02:22Z No. of bitstreams: 1 Ivens Giuliano Campos dos Santos_.pdf: 1924047 bytes, checksum: c7a70b1abd74046b038c1ae7a6008606 (MD5) / Made available in DSpace on 2019-03-22T13:02:22Z (GMT). No. of bitstreams: 1 Ivens Giuliano Campos dos Santos_.pdf: 1924047 bytes, checksum: c7a70b1abd74046b038c1ae7a6008606 (MD5) Previous issue date: 2018-12-19 / Nenhuma / Com a criação do Centro Integrado de Comando e Controle (CICC) e após transcorridos grandes eventos como a Copa do Mundo e as Olimpíadas, perpetuando-se o CICC como “legado” para a comunidade gaúcha, surgiu a pergunta: quais são os fatores facilitadores e as barreiras para o compartilhamento e a integração das informações entre os órgãos públicos envolvidos no Centro Integrado de Comando e Controle (CICC) de Segurança Pública do Rio Grande do Sul? Usando o método qualitativo, em um estudo de caso, a pesquisa envolveu informantes chaves como gestores das instituições envolvidas no CICC e gestores de TI para a coletas de dados. A pesquisa analisou as respostas dos entrevistados por categorias teóricas indicadas pela literatura. O CICCR (Centro Integrado de Comando e Controle Regional), no caso do Rio Grande do Sul chamado de Departamento de Comando Integrado de Comando e Controle, é o elemento de coordenação da Operação de Segurança regional, que visa assegurar o fluxo de informação de interesse nacional para o CICCN (Centro Integrado de Comando e Controle Nacional) e de interesse operacional para as estruturas acessórias. Analisando as entrevistas e um evento crítico observado, foram consideradas três perspectivas teóricas. Na perspectiva política, houve a colaboração das partes e boa vontade política. Quanto à perspectiva gerencial e organizacional, cabe destacar as dificuldades de planejamento e apuração dos custos da operação. Já na perspectiva tecnológica, é importante o planejamento adequado da tecnologia a ser utilizada durante as operações e sua constante atualização. Existem fatores que podem ser tanto facilitadores, como barreiras, dependendo de como são trabalhados. Da mesma forma, embora a tecnologia desempenhe um papel importante, a perspectiva política e gerencial se sobrepõe. / With the creation of the Integrated Command and Control Center (CICC) and after major events such as the World Cup and the Olympics, and the CICC was perpetuated as a "legacy" for the community of Rio Grande do Sul, the question arose: what are the facilitating factors and the barriers to information sharing and integration among public agencies involved in the Rio Grande do Sul Integrated Public Security Command and Control Center (CICC)? Using the qualitative method, in a case study, the survey involved key informants as managers of institutions involved in CICC and IT managers for data collection. The research analyzed the answers of the interviewees by theoretical categories indicated by the literature. The CICCR (Integrated Command and Control Center), in the case of Rio Grande do Sul called the Command and Control Integrated Command Department, is the coordinating element of the Regional Security Operation, which aims to ensure the flow of information of interest national level for the CICCN (Integrated Command and National Control Center) and operational interest for ancillary structures. Analyzing the interviews and an observed critical event, three theoretical perspectives were considered. In political terms, there was the collaboration of the parties and political will. Regarding the managerial and organizational perspective, it is important to highlight the difficulties in planning and calculating the costs of the operation. In the technological perspective, the adequate planning of the technology to be used during operations and its constant updating is important. There are factors that can be both facilitators and barriers depending on how they are worked. In the same way, although technology plays an important role, the political and managerial perspective overlaps.
55

Proposta de modelo para estruturação de centros de controle integrados em cidades médias / Model proposal for structuring of Integrated Control Centers (ICC) in medium-sized cities

Bruhn, Jessie Carvalho January 2017 (has links)
As cidades, notadamente aquelas identificadas como de porte médio, acabam absorvendo mudanças de qualidade e passam a centralizar atividades econômicas. Se, por um lado, a urbanização traz oportunidades para o desenvolvimento social e econômico, de outro, resulta em significativa perda nas funcionalidades básicas e exerce pressão sobre as infraestruturas e recursos naturais. As Tecnologias da Informação e Comunicação (TIC) surgem como aliadas no enfrentamento a estes desafios. Baseadas no uso das TIC, iniciativas de Cidades Inteligentes exploram a instrumentalização das infraestruturas da cidade. Na tentativa de unificar a gestão dos diversos aspectos das cidades, por meio do monitoramento e análise em tempo real de dados públicos, diversas capitais estaduais do Brasil já contam com o suporte de centros de controle integrados. Dado o exposto, o presente trabalho propõe um modelo para a estruturação de Centros de Controle Integrados (CCI), compatíveis com a realidade de municípios de médio porte. Para tanto, por meio da revisão da literatura e de uma entrevista junto ao Centro Integrado de Comando da Cidade de Porto Alegre (CEIC), realizou-se o levantamento das melhores práticas a respeito da implantação de centros de controle. Complementarmente, entrevistaram-se os responsáveis de quatro prefeituras municipais para a determinação dos modelos de controle instituídos em cidades de médio porte. Para fins de validação, deu-se a avaliação do modelo por três especialistas da área de estudo. O modelo proposto – composto pelas dimensões de (i) coordenação, (ii) design, (iii) gerenciamento, (iv) comunicação, (v) práticas e rotinas de trabalho e (vi) processamento e gerenciamento de evidências, resulta do cruzamento destas informações e contribui, como ferramenta de gestão, para o desenvolvimento estruturado das cidades de médio porte. / The cities, especially those identified as medium-sized cities, end up absorbing quality changes and begin to centralize economic activities. If, on the one hand, urbanization brings opportunities for social and economic development, on the other hand, it results in a significant loss of basic functionalities, jeopardizing infrastructure and natural resources. In this way, Information and Communication Technologies (ICT) emerge as an alliy in face of these challenges. Based on the use of ICT, Smart Cities initiatives explore the instrumentalization of the city's infrastructures. In an attempt to unify the management of the various aspects of cities through real-time monitoring and analysis of public data, several state capitals in Brazil already rely on the support of Integrated Control Centers. Thus, the present work proposes a model for structuring the Integrated Control Centers (ICC), compatible with the reality of medium-sized municipalities. Through a literature review and an interview with the Centro Integrado de Comando of Porto Alegre (CEIC), the best practices regarding the implementation of control centers were surveyed. Complementarily, the heads of four city halls were interviewed to determine the control models established in medium-sized cities. Furthermore, the model was also assessed by three specialists in the study area. The proposed model - composed by the dimensions of (i) coordination, (ii) design, (iii) management, (iv) communication, (v) practices and work routines and (vi) processing and management of evidence, results from the cross-referencing of this information and contributes as a management tool to the structured development of medium-sized cities.
56

Circadian rhythms and effects of different diets on the development and reproduction of Nabis Kinbergii (Hemipteria : Nabidae).

Nguyen, Quang Huu January 2008 (has links)
Nabis kinbergii is a native polyphagous predator in Australia. It has been found in all states and territories of Australia. N. kinbergii has been regarded as an efficient predator of many insect pests in lucerne, cotton and particularly brassica crops. The circadian rhythms, the effects of different prey on development and reproduction, and prey preferences of N. kinbergii have not been studied in South Australia. These are the subjects of this thesis. N. kinbergii is more active at night than in the day. They seemed to be still more frequently at dawn and more active at dusk under natural environmental conditions. Yet, their behaviour was possibly different when they were held in a controlled environment with artificial light. Under both natural and artificial lighting conditions, they would spend more time moving on plants at night. They spent less time moving than other activities. Furthermore, they were more active during the second day of the observations, probably because of the hunger. A mixed diet including Plutella xylostella, Myzus persicae and Brevicoryne brassicae brought the most significant positive influences to the development, survival and longevity of N. kinbergii. It had a shorter preoviposition period and greater egg production when fed on P. xylostella than when fed on M. persicae. Among the three prey, B. brassica was the poorest food because the survival rate between egg hatch and adult eclosion was only 7.5 %, compared to 85 %, 92.5 % and 97.5 % when N. kinbergii fed on M. persicae, P. xylostella and a mixed diet, respectively. Evidence of prey preference was exhibited by N. kinbergii. B. brassica seemed to be the least preferred food. N. kinbergii possibly attacked less mobile prey and delayed eating prey with poor nutrition or that were toxic. In wind tunnel experiments, N. kinbergii may have been attracted by plant volatiles rather than prey odour. These findings may help to refine the timing of experiments and improve the understanding of the role of this predator in integrated pest management. / Thesis (M.Sc.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008
57

Studies of integrated control of selected root diseases of sunflowers using Trichoderma harzianum (ECO-T®) and silicon

Elungi, Konis. January 2009 (has links)
The soil-borne fungi Rhizoctonia solani Kuhn and Sclerotinia sclerotiorum De Bary are ubiquitous plant pathogens with a wide host range. They are among the most widespread and destructive diseases of many crops, including sunflowers. Although in many cases, the use of chemicals appears to be the most economical and efficient means of controlling plant pathogens, their environmental concerns and the development of tolerance in pathogen populations have led to drastic reduction in their usage and increased the need to find alternative means of disease control. The potential benefits of applying Trichoderma harzianum Rifai and silicon (Si) nutrition to plants have been extensively reviewed. In this study, the ability of T. harzianum (Eco-T®), soluble silicon, and their combination was evaluated on sunflower (Helianthus annuus L.), for their potential to suppress pathogenic strains of R. solani and S. sclerotiorum. The ability of this crop to take up and accumulate Si in different plant parts was also investigated. In vitro assessment of fungal responses to Si in PDA showed that both R. solani and S. sclerotiorum were inhibited in the presence of Si. More inhibition was observed as the Si concentration increased with a relative increase in pH. Maximum growth inhibition was observed at 3000 mg ;-1 – 6000 mg ;-1 of PDA. No difference in inhibition between the two pathogens was observed, thus confirming the fungitoxic/suppressive ability of high Si concentrations to fungal growth. In addition, in vivo trials showed that the Si concentration of 200 mg ;-1 applied weekly significantly increased the dry weight of plants inoculated with R. solani and S. sclerotiorum and was therefore considered the optimum concentration. Assessments on in vitro antifungal activities of Eco-T® on R. solani and S. sclerotiorum, showed that Eco-T® significantly inhibited mycelial growth, in both dual culture methods and volatile and non-volatile compounds produced by Eco-T®. In addition, the combination of Eco-T® and Si was most effective in suppressing damping-off and increasing plant dry weight of sunflower seedlings in the greenhouse. The combination of Si and Eco-T® significantly increased percentage germination, number of leaves and head dry weight of the sunflower cultivars tested. Silicon alone increased growth but was unable to control R. solani and S. sclerotiorum effectively. Rhizotron studies showed that S. sclerotiorum infected the host through the roots and the stem, whereas R. solani only infected the host through the roots. A study on Si uptake and distribution showed that sunflower accumulates Si in various plant tissues. Analysis of plant tissues revealed that more Si was accumulated in leaves > stems > roots, with the Si levels in leaves being significantly higher than in stems and roots. In conclusion, Si alone could be used to increase growth but was unable to control R. solani and S. sclerotiorum. However, Si together with Eco-T® provides an environmentally friendly alternative for the control of R. solani and S. sclerotiorum, and enhanced plant growth and yield. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
58

Bases para el desarrollo de un sistema integrado de control de malezas en el establecimiento de plantaciones de Populus spp. del centro-norte de la provincia de Buenos Aires, Argentina

Achinelli, Fabio Germán January 2007 (has links)
El objetivo general de esta tesis fue producir información científico-tecnológica básica para la implementación de un sistema integrado de control de malezas, que permita reemplazar al sistema mecánico en las plantaciones de álamo (Populus spp.) del centro-norte de la Provincia de Buenos Aires. Los trabajos se agruparon en tres líneas de investigación complementarias, en donde se abordaron grupos específicos de problemas. En la primera línea de trabajo se determinó la composición específica de la comunidad de malezas y la magnitud de su interferencia, se establecieron los niveles de control y fitotoxicidad que producen diferentes herbicidas, y se evaluaron en forma comparada los efectos sobre la supervivencia y el crecimiento del cultivo de distintos tratamientos integrados de control respecto del sistema actual. La segunda línea estudió la variación temporal de la interferencia en busca de la definición del período crítico para el control de malezas, y en la tercera línea de trabajo se evaluó el resultado económico potencial de la implementación de los cambios estudiados en el sistema de control, considerando diferentes escenarios económico-financieros, grados de incorporación de tecnología y de reemplazo de mano de obra. Las distintas líneas comprendieron experiencias en campo llevadas a cabo entre los años 1998 y 2004 en el Establecimiento Forestal "María Dolores", Partido de Alberti, Provincia de Buenos Aires (34° 50' Lat. Sur; 60° 30' Long. Oeste; 55 msnm). Los trabajos se efectuaron siguiendo una estrategia progresiva de experimentación: en una primera etapa se realizaron ensayos exploratorios y posteriormente los resultados iniciales obtenidos fueron evaluados en ensayos a escala de producción y parcelas demostrativas de 5 hectáreas de superficie.
59

Estratégia integrada de regulação de tensão e do fator de potência de um sistema de distribuição usando uma rede sem fio / Integrated voltage regulation and power factor control strategy to distribution system using a wireless network

Mariano, Rafael Fernando 31 October 2017 (has links)
Submitted by RAFAEL FERNANDO MARIANO null (mariano.rafael@outlook.com) on 2017-12-21T18:42:51Z No. of bitstreams: 1 Rafael_Dissertação_Digital_Revisao_FINAL.pdf: 2427309 bytes, checksum: 032f6de48703baf01dc996ef0b00e063 (MD5) / Approved for entry into archive by Minervina Teixeira Lopes null (vina_lopes@bauru.unesp.br) on 2017-12-22T10:58:02Z (GMT) No. of bitstreams: 1 mariano_rf_me_bauru.pdf: 2366747 bytes, checksum: cbc5abe78e5f08900855037b7bf5458b (MD5) / Made available in DSpace on 2017-12-22T10:58:02Z (GMT). No. of bitstreams: 1 mariano_rf_me_bauru.pdf: 2366747 bytes, checksum: cbc5abe78e5f08900855037b7bf5458b (MD5) Previous issue date: 2017-10-31 / A preocupação com a qualidade da energia elétrica, seu uso e técnicas para redução de perdas elétrica não é mais uma tendência e sim uma necessidade, pois, tem se entendido que a energia elétrica é um bem comum e não deve ser desperdiçada. Nesse contexto, estratégias para controlar o nível de tensão e o fator de potência vêm sendo tratadas, com o objetivo de aprimorar o controle dessas variáveis. Este trabalho apresenta uma estratégia de controle integrado de regulação de tensão e do fator de potência para um sistema de distribuição de energia elétrica usando uma rede de comunicação sem fio. A estratégia de controle proposta consiste em uma rede de comunicação entre os dispositivos designados para operarem reguladores de tensão, transformadores com comutadores sob carga e banco de capacitores, concentrando as informações em um único dispositivo capaz de definir a operação dos demais dispositivos alocados no sistema, sendo a concentração das informações feita localmente, sem a necessidade de um sistema de controle centralizado, permitindo uma simplificação e uma redução significativa de custo para implementação de uma solução de controle integrado de tensão e do fator de potência. A estratégia de controle proposta foi modelada no ambiente Matlab®/Simulink® e a rede de comunicação na ferramenta TrueTime. O estudo apresenta uma comparação entre a estratégia proposta e o método de controle tradicional, abordando aspectos relacionados a qualidade de energia elétrica entregue, demanda de energia em horários de alto consumo e perdas elétricas no sistema simulado. Os resultados mostram que a estratégia de controle local integrado de tensão e fator de potência permite a aplicação de banco de capacitores a jusante de reguladores de tensão sem impactar a qualidade de energia elétrica, ainda permite a técnica de redução de tensão com o intuito de reduzir a demanda de energia principalmente em horários de pico de consumo. E por fim apresenta uma redução de perdas elétricas de quase 4%, comparado com a estratégia de controle tradicional. / The issue about power quality, its rational use, and techniques to reduce electrical losses in the distribution systems is not anymore a trend but a necessity, due to, a understanding that the electricity is a common good, then, should not be wasted. Based on this context, strategies have been studying to control the voltage and power factor with the objective to improve the control of this variables. This work presents an integrated control for voltage and power factor strategy to distribution systems using a wireless network. The purposed strategy allows a communication between the devices designed to operate voltage regulators, on load transformers tap changers, and capacitors bank, concentrating all information in only one device, which is able to define the operation of others, being the concentration information made locally, without a necessity of the a centralize system, simplifying and reducing costs related the implementation of an integrated control for voltage and power factor. The strategy presented was modeled in the Matlab®/Simulink® and the communication network using the TrueTime toolbox. The study presents a comparison between the traditional strategy and the purposed, analyzing the power quality delivered, power demand in peak time, and electrical losses in the system. The results shows that the integrated control for voltage and power factor strategy allows the use of capacitors bank downstream of voltage regulators without any impact in the power quality supplied, besides that, it is possible to reduce the power demand lowering the voltage using the conservative voltage reduction function, to finish a reducing in electrical losses about 4% is achieved with the strategy purposed when compared with the traditional.
60

Creating a common business logic : A case study about strategic congruence and integrated control at Tekniska verken in Linköping AB

Thanhäuser, Marc, Lindblad, Emanuel January 2018 (has links)
Background – The energy sector is experiencing instability and energy companies must embrace more flexible structures and strategic initiatives to remain relevant. Purpose – To gain understanding about the challenges with implementing strategic congruence and integrated control in umbrella organizations and how their interplay can contribute to achieving a common business logic. Methodology – In the scope of a single case study, we conducted 20 interviews on corporate, business and functional level at Tekniska verken in Linköping AB. The ‘tentative model’ of Nilsson and Rapp (2005) was re-assessed to examine a common business logic. Findings – Our empirical findings indicated that the businesses of umbrella organizations can be diverse while simultaneously being congruent. When addressing strategic congruence, it is challenging because transparent communication and collaboration between business areas as well as optimizing organizational structures and designing clear responsibility areas is difficult to achieve. Regarding integrated control, it is not easy to realize because the corporate plan needs wide acceptance and breaking down complex content to the business areas is challenging. Not to mention that a common frame of reference regarding terminology and alike control standards requires high commitment.

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