Sucrose is a signal molecule in assimilate partitioning

The proton–sucrose symporter mediates the key transport step in the resource distribution system that allows many plants to function as multicellular organisms. In the results reported here, we identify sucrose as a signaling molecule in a previously undescribed signal-transduction pathway that regulates the symporter. Sucrose symporter activity declined in plasma membrane vesicles isolated from leaves fed exogenous sucrose via the xylem transpiration stream. Symporter activity dropped to 35–50% of water controls when the leaves were fed 100 mM sucrose and to 20–25% of controls with 250 mM sucrose. In contrast, alanine symporter and glucose transporter activities did not change in response to sucrose treatments. Decreased sucrose symporter activity was detectable after 8 h and reached a maximum by 24 h. Kinetic analysis of transport activity showed a decrease in Vmax. RNA gel blot analysis revealed a decrease in symporter message levels, suggesting a drop in transcriptional activity or a decrease in mRNA stability. Control experiments showed that these responses were not the result of changing osmotic conditions. Equal molar concentrations of hexoses did not elicit the response, and mannoheptulose, a hexokinase inhibitor, did not block the sucrose effect. These data are consistent with a sucrose-specific response pathway that is not mediated by hexokinase as the sugar sensor. Sucrose-dependent changes in the sucrose symporter were reversible, suggesting this sucrose-sensing pathway can modulate transport activity as a function of changing sucrose concentrations in the leaf. These results demonstrate the existence of a signaling pathway that can control assimilate partitioning at the level of phloem translocation.

Planejamento de sistemas de distribuição de energia elétrica considerando questões de confiabilidade e risco

O problema de Planejamento da Expansão de Sistemas de Distribuição (PESD) visa determinar diretrizes para a expansão da rede considerando a crescente demanda dos consumidores. Nesse contexto, as empresas distribuidoras de energia elétrica têm o papel de propor ações no sistema de distribuição com o intuito de adequar o fornecimento da energia aos padrões exigidos pelos órgãos reguladores. Tradicionalmente considera-se apenas a minimização do custo global de investimento de planos de expansão, negligenciando-se questões de confiabilidade e robustez do sistema. Como consequência, os planos de expansão obtidos levam o sistema de distribuição a configurações que são vulneráveis a elevados cortes de carga na ocorrência de contingências na rede. Este trabalho busca a elaboração de uma metodologia para inserir questões de confiabilidade e risco ao problema PESD tradicional, com o intuito de escolher planos de expansão que maximizem a robustez da rede e, consequentemente, atenuar os danos causados pelas contingências no sistema. Formulou-se um modelo multiobjetivo do problema PESD em que se minimizam dois objetivos: o custo global (que incorpora custo de investimento, custo de manutenção, custo de operação e custo de produção de energia) e o risco de implantação de planos de expansão. Para ambos os objetivos, são formulados modelos lineares inteiros mistos que são resolvidos utilizando o solver CPLEX através do software GAMS. Para administrar a busca por soluções ótimas, optou-se por programar em linguagem C++ dois Algoritmos Evolutivos: Non-dominated Sorting Genetic Algorithm-2 (NSGA2) e Strength Pareto Evolutionary Algorithm-2 (SPEA2). Esses algoritmos mostraram-se eficazes nessa busca, o que foi constatado através de simulações do planejamento da expansão de dois sistemas testes adaptados da literatura. O conjunto de soluções encontradas nas simulações contém planos de expansão com diferentes níveis de custo global e de risco de implantação, destacando a diversidade das soluções propostas. Algumas dessas topologias são ilustradas para se evidenciar suas diferenças.

Aplicações híbridas entre sistemas multiagentes e técnicas de inteligência artificial para redes inteligentes de distribuição de energia elétrica

Os smart grids representam a nova geração dos sistemas elétricos de potência, combinando avanços em computação, sistemas de comunicação, processos distribuídos e inteligência artificial para prover novas funcionalidades quanto ao acompanhamento em tempo real da demanda e do consumo de energia elétrica, gerenciamento em larga escala de geradores distribuídos, entre outras, a partir de um sistema de controle distribuído sobre a rede elétrica. Esta estrutura modifica profundamente a maneira como se realiza o planejamento e a operação de sistemas elétricos nos dias de hoje, em especial os de distribuição, e há interessantes possibilidades de pesquisa e desenvolvimento possibilitada pela busca da implementação destas funcionalidades. Com esse cenário em vista, o presente trabalho utiliza uma abordagem baseada no uso de sistemas multiagentes para simular esse tipo de sistema de distribuição de energia elétrica, considerando opções de controle distintas. A utilização da tecnologia de sistemas multiagentes para a simulação é baseada na conceituação de smart grids como um sistema distribuído, algo também realizado nesse trabalho. Para validar a proposta, foram simuladas três funcionalidades esperadas dessas redes elétricas: classificação de cargas não-lineares; gerenciamento de perfil de tensão; e reconfiguração topológica com a finalidade de reduzir as perdas elétricas. Todas as modelagens e desenvolvimentos destes estudos estão aqui relatados. Por fim, o trabalho se propõe a identificar os sistemas multiagentes como uma tecnologia a ser empregada tanto para a pesquisa, quanto para implementação dessas redes elétricas.

Compactação e elevação da vida útil de transformadores de distribuição empregando óleo vegetal isolante.

A busca no aumento da vida útil dos transformadores de distribuição, redução dos custos de manutenção e mitigação de falhas, leva ao desenvolvimento de novos materiais e critérios de exploração diferenciados desses ativos. Esta pesquisa apresenta o desenvolvimento de um novo transformador de distribuição compacto e mais eficiente utilizando óleo vegetal isolante totalmente biodegradável. Além de biodegradável, o óleo vegetal utilizado possui menor agressividade ambiental e maior capacidade térmica aumentando, a capacidade de carregamento do transformador sem comprometer a sua vida útil. A fim de atestar essa menor agressividade em relação ao óleo mineral, ensaios foram efetuados em um equipamento que permaneceu 12 anos em operação. O equipamento foi totalmente desmontado para análise e coleta de amostras de papel e óleo vegetal isolante. As análises visam comprovar a menor agressividade em relação ao óleo mineral, apresentadas na revisão bibliográfica. A menor agressividade torna possível a proposição de uma nova filosofia de planejamento de redes de distribuição utilizando uma quantidade menor dos novos transformadores para uma mesma carga, tornando-a mais compacta e eficiente.

Irrigation practice and engineering.

Contains bibliographies.

Questions in Narratives from Oral Tradition to Literature

Thesis (Ph.D.)--University of Washington, 2016-06

Modeling of Distributed Generation under Next Generation Interconnection Requirements

Thesis (Master's)--University of Washington, 2016-06

Inter-organizational co-operation, conflict and change

Relationships between organizations can be characterized by cooperation, conflict, and change. In this dissertation we study cooperation between organizations by investigating how norms in relationships can enhance innovativeness and subsequently impact relationship performance. We do so by incorporating both beneficial aspects of long term relationships as well as “dark side” factors that may decrease innovativeness. This provides a balanced assessment of the factors increasing and decreasing the performance of relationships. Next, we study conflict between organizations by taking a network view on conflict which helps explain why organizations react to conflict. We find stakeholders to have an effect on channel conflict responsiveness. Finally we study change by means of an organization’s ability to successfully add an Internet channel to their distribution system in order to sell its products or services directly to the end-user. We find that an Internet channel is best implemented by organizations that are flexible and we identify several circumstances under which this flexibility is highest.

Flow patterns on sieve trays

Studies into gas-liquid flow patterns were carried out on commercial scale sieve trays where the ratio of froth depth to flow path length is typical of that found in practice. Experiments were conducted on a 2.44 m diameter air-water distillation simulator, in which flow patterns were investigated by direct observation, using directional flow pointers; by water cooling, to simulate mass transfer; and by height of clear liquid measurements across the tray. The flow rates used are typical of those found in practice. The approach adopted was to investigate the effect of the gas flow on the liquid flow by comparing water only flow patterns across an unperforated tray with air-water flow patterns on perforated trays. Initial gas-liquid contacting experiments on the 6.35 mm hole tray showed that, under certain conditions, the gas flow pattern beneath the test tray can have a significant effect on the tray liquid flow pattern such that gas-driven liquid circulation was produced. This was found to be a function of this particular air-water simulator design, and as far as is known this is the first time that this phenomenon has been observed. Consequently non-uniform gas flow effects were removed by modification of the gas distribution system. By eliminating gas circulation effects, the effect of the gas flow on the separation of liquid flow was similar to that obtained on the 1.0 mm hole tray (Hine, 1990). That is, flow separation occurred at the ends of the inlet downcomer which produced large circulating zones along the tray segments both on the non-perforated and perforated trays. The air when forced through the liquid, inhibited circulating flow such that it only occurred at high water inlet velocities. With the 6.35 mm hole tray, the growth and velocity of circulating flow was reduced at high superficial air velocities, and in the experiments to simulate distillation, liquid was in forward flow over most of the tray.

Using discrete event simulation to investigate road delivery policies to UK retailers

Retail customers provide a number of significant challenges to the efficiency and effectiveness of distribution systems. These challengers include shorter delivery windows, fluctuating volumes and a wider product mix. This paper demonstrates the use of discrete-event simulation to investigate policy issues regarding the incorporation of retail customers in a road delivery network from the spoke terminal of a hub and spoke distribution system. In particular a comparison of a mixed (retail and non-retail) delivery policy with a dedicated retail delivery run is made.

Marketing és vállalatközi kapcsolatok - Kutatócsoport zárótanulmány

Tanulmányunkban a Marketing és Vállalatközi kapcsolatok kutatócsoport 2011-ben készült műhelytanulmányainak legfontosabb eredményeit mutatjuk be. Kutatásaink központi témája a vállalati versenyképesség, illetve annak vizsgálata, hogy a vállalatok tevékenységének egyes területei hogyan járulnak hozzá a vállalatok versenyképességének növeléséhez. Elemzéseink a Budapesti Corvinus Egyetem Vállalatgazdaságtan Intézete Versenyképesség Kutató Központja által vezetett „Versenyben a világgal” kutatási program nagyszabású kérdőíves felmérésén alapulnak, amely során 300 vállalat vezetőit kérdeztek meg 2009-ben. Eredményeink közül kiemeljük, hogy a piacorientáció szintje a vizsgált vállalati körben az átlagosnál valamivel jobb, azonban a marketingkoncepció jobb megvalósítása érdekében a vállalatoknak a versenytárs-orientációjukat kellene elsősorban erősíteniük. Fontos következtetése a kutatásnak a vezető vállalatok gyakorlatának feltérképezése, e kategóriát egy összetett teljesítménymutató alapján alakítottunk ki. Eredményeink szerint a vezető vállalatok a piacorientáció mértékében, a márkázásban, a disztribúció kiterjedtségében, valamint változatosságában, a marketing erőforrásokban és képességekben és a vállalati hálózatban betöltött pozíció terén erősebbek az átlagosan teljesítőktől és/vagy a lemaradóktól. ----- Abstract: In this research paper we present the most important results of the research papers prepared by the research group „Marketing and Interfirm Relationship” in 2011. The central theme of our research papers is corporate competitiveness. We investigate the ways the different activities of firms contribute to the increase of their competiveness. Our analyses are based on a large scale survey carried out by the Competitiveness Research Center of Corvinus University Of Budapest, in which 300 company executives were surveyed in 2009. Among our results we highlight that market orientation of Hungarian firms is little above the average in our sample, however a better implementation of the marketing concept would require a stronger emphasis on competitor orientation. An important conclusion of our research is the description of the practice of leading companies, a category created in terms of a complex performance measurement. Our results suggest that leading companies show a higher level of market orientation, a more sophisticated branding practice, a more extended distribution system with a higher degree of variablity, stronger marketing resources and capabilities and a stronger position in the firm’s network than companies with average performance and/or laggards.

The New (Marketing) Role of Firms as Media Content Providers – The case of SME’s Strategic Social Media Presence

In the new social media context, it is gradually more common to say that each party can itself be considered a media content provider, firms included (through their brand pages). This tendency is reflected in a rising professional field called “content marketing”. This study incorporates the perspective of small and medium-sized enterprises (SMEs) into the scope of social media (SM) as a marketing communications and media content distribution system. In an exploratory content analysis of 20 official SM brand pages with 1281 analyzed posts the authors study how SMEs respond to the advent of a new paradigm of marketing communications with special attention to their usage of media-specific contents. SM impels companies to eventually rethink the traditional one-way communication flow of their marketing messages and to incorporate a new, two-way communication into their marketing strategy, where (their engaged and involved) users can create, modify, share and discuss content related to the firm’s activity. This study’s preliminary results show that diffusing content generally acts for SMEs as a facilitator to involve fans by offering a thematized space for them to manifest themselves in company-related topics. Therefore, content adds to the firms’ possibilities of brand positioning by offering a reflection of fans’ company- and contentrelated behavior, which is a supplementary source of information.

Guest Editorial: Debunking the Myths

The modem retail travel industry has been plagued by myths created by popular media in an effort to create hype and readership, rather than report an accurate portrayal of the extraordinary health of the travel distribution system. Regardless of the structural changes in the travel industry, the outlook for growth and profitability of travel agencies and travel agents has never been better

Reaproveitamento de condensado e vapor flash em uma planta têxtil com ênfase no setor de acabamento

This study focused object a steam generation system, steam distribution and condensate return a textile plant located in Rio Grande do Norte. The work was based on the following objectives: Knowing the use of saturated water vapor in the dyeing and finishing processes in a textile plant; To study the various aspects of a steam distribution system to identify the ways in which energy losses occur; Obtain quantitative information of the main loss in steam generation system and steam distribution and to measure the losses, water and steam system; Using the flash steam as a means of cost reduction. For it was made use of the calculation of financial gains made in their respective improvements. As a database for the development of working registers are used in industrial processes, data from utility systems, laboratory data analysis and on-line analyzers, covering the period 2013. Using the principles set conservation laws mass and energy, those data showed that the loss of water and energy in the steam system are significant and that the environmental and economic gains to be obtained with improvement actions are quite significant. Based on the data and results suggest that future studies deem the continuity approach to steam generation systems, distribution and mainly condensate return.

Sistema detector de vazamentos em instalações prediais de água fria

Building installations of cold water are key parts in any model of housing, are homes or condos. However, these systems are subject to failure, which can range from a leak in a device until faults in the structure of water reservoirs and distribution system. These faults are responsible for great economic and environmental costs. In order to reduce these losses, this work proposes the development of a system able to detect the presence and identify some types of water leaks that may occur. For implementation and testing, consumption model was used in a simulator capable of reproducing a similar behavior to a real model and its consequent failures. The detection of leaks is done based on an expert like model having two detection modules, one active and one passive, which use an array of sensors and actuators (valves) to do the sensing. For testing and implementation has been developed a software capable of coupling the system simulator and detector. From the results it can be seen that the system proposed in this work, as well as functioning satisfactorily, can be easily implemented in microcontrollers or embedded systems due to its simplicity.