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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Coupling of ecological and water quality models for improved water resource and fish management

Tillman, Dorothy Hamlin 15 May 2009 (has links)
In recent years new ideas for nutrient management to control eutrophication in estuarine environments have been under consideration. One popular approach being considered in the Chesapeake Bay Program is called the “top down” approach based on the premise that restoring algal predators, such as oysters and menhaden, will limit excess phytoplankton production and possibly eliminate costly nutrient control programs. The approach is being considered to replace or use in conjunction with the “bottom up” approach of reducing nutrient loads. The ability to model higher trophic levels such as fish, as well as the eutrophication processes driving production of primary producers in an aquatic ecosystem is needed. CE-QUAL-ICM (ICM) and Ecopath were two models selected for this research. ICM is a time- and spatial-varying eutrophication model that uses nutrient loads to predict primary producers, while Ecopath is a static mass balance model representing an average time period (e.g., season or year) and uses values of primary producers and other groups to predict fish biomass. Linking the two models will provide the means of going up the food chain by trophic levels. The Chesapeake Bay was chosen as the study site since both models are in use there. Before coupling ICM and Ecopath, common links between the two models were found. Ten groups were identified with such variables as production rates, consumption rates, and unassimilated food/consumption. A post-processor/subroutine was developed for ICM to aggregate output data from 3-D to 0-D to be used in Ecopath. Two Ecopath runs were developed with data from ICM and the Chesapeake Bay (CB) Ecopath model to see how network interactions differed with data representing the same system. Four additional runs were made, creating perturbations (i.e., increased phytoplankton production) using the CB Ecopath model and replacing the primary producers with data from ICM. Final runs of ICM were conducted looking at adjusting three parameters to try to restore the Bay back to 1950 conditions. It was demonstrated that ICM data can be coupled with Ecopath to study management strategies in eutrophication. Because of model formulations there was no data exchange from Ecopath back to ICM.
2

Enquadramento de corpos d’água no nordeste brasileiro como instrumento de gestão e sustentabilidade ambiental: o caso da bacia hidrográfica acarape do meio - ce / Framework of water bodies in the Brazilian northeast like management instrument and environmental sustainability: the case of the hydrographic basin of Acarape of Meio - CE

Lima, Berthyer Peixoto January 2016 (has links)
LIMA, Berthyer Peixoto. Enquadramento de corpos d’água no nordeste brasileiro como instrumento de gestão e sustentabilidade ambiental: o caso da bacia hidrográfica acarape do meio – CE. 2016. 270 f. Tese (Doutorado em Engenharia Agrícola)-Universidade Federal do Ceará, Fortaleza, 2016. / Submitted by Anderson Silva Pereira (anderson.pereiraaa@gmail.com) on 2017-01-25T21:25:01Z No. of bitstreams: 1 2016_tese_bplima.pdf: 13310559 bytes, checksum: 30f2c6f24776ebb05e9b1ee263e21686 (MD5) / Approved for entry into archive by Jairo Viana (jairo@ufc.br) on 2017-01-26T20:31:44Z (GMT) No. of bitstreams: 1 2016_tese_bplima.pdf: 13310559 bytes, checksum: 30f2c6f24776ebb05e9b1ee263e21686 (MD5) / Made available in DSpace on 2017-01-26T20:31:44Z (GMT). No. of bitstreams: 1 2016_tese_bplima.pdf: 13310559 bytes, checksum: 30f2c6f24776ebb05e9b1ee263e21686 (MD5) Previous issue date: 2016 / The State of Ceará has become a watershed in the management of water resources in Brazil for being one of the first States in the approval of the state law of water resources and for having the first experience in Brazil in charging for using gross water However this huge breakthrough was not enough to implement one of the most important management tools the framework of water bodies the more precise tool to link water resources and environmental managements The disinterest and difficulties to implement the framework in the semiarid region and Brazil of northeast lies in the fact that the available water is derived from stored water by intermittent rivers that flow in uncertain four months of the year lack of public policies that still allow the absence of sanitation transform their reservoirs in warehouses of untreated effluents and a lack of a pragmatic methodology that can stimulate collegiate bodies of water resources to implement this instrument Even with the 357/2005 CONAMA resolution and the 91/2008 CNRH resolution which define quality standards and a flowchart with procedures for implementing the framework these tools are still ineffective in the semiarid region whose only certainty is periods of water scarcity This research has proposed a challenging and different methodology which innovates in the social axis when working with Water System Managing Committees rather than simple public consultations with the creation of a Working Group within the Basin Committee as an arm of itself and provide scientific tools that can assist in the process of diagnosis prognosis and monitoring of goals For the modeling of water quality at the Pacoti River the QUAL-UFMG model was used taking into account monitoring data of DO BOD phosphorus and coliform thermotolerant at the control sections for its calibration and validation For the modeling of water quality at the Acarape reservoir an innovative model called QUAL-HIDROSED was proposed with focus on the simulation of the total phosphorus parameter The diagnosis revealed that the entire stretch of the Pacoti River and the reservoir are in class 4 One of the most important products of this research was the approval by the Basin Committee of the first framework proposal for a reservoir in the northeast region depending on the storage volume and phosphorus load Recently this framework proposal was submitted to the Water Resources Council of the State of Ceará as the first experience in framing of water bodies in the Brazilian northeast region / O Estado do Ceará tornou-se um divisor de águas na gestão dos recursos hídricos no Brasil dentre outros motivos por ter sido um dos Estados pioneiros na homologação da lei estadual de recursos hídricos e por ter vivenciado a primeira experiência no Brasil em cobrança pelo uso da água bruta No entanto todo esse enorme avanço não foi suficiente para implementar um dos mais importantes instrumentos de gestão o enquadramento dos corpos d’água o instrumento de gestão mais preciso para interligar a gestão dos recursos hídricos com a gestão ambiental O desinteresse e as dificuldades para se implementar o enquadramento na região semiárida e nordeste do Brasil reside no fato de que o recurso hídrico disponibilizado é oriundo de água estocada por rios intermitentes que correm em incertos quatro meses do ano por vácuos de políticas públicas que ainda permitem que a ausência de saneamento básico transforme os reservatórios em armazéns de efluentes não tratados e por falta de uma metodologia pragmática que possa estimular órgãos colegiados de recursos hídricos a implementar esse instrumento Mesmo com a resolução CONAMA 357/2005 e a resolução do CNRH nº 91/2008 que definem os padrões de qualidade e um fluxograma com procedimentos para implementação do enquadramento ainda assim essas ferramentas são ineficazes para a região semiárida cuja única certeza é a de períodos de escassez hídrica Esta pesquisa veio propor uma metodologia diferenciada inovando no eixo social ao se trabalhar com Comissões Gestoras de Sistemas Hídricos ao invés de simples consultas públicas bem como com a criação de um Grupo de Trabalho dentro do Comitê de Bacia Hidrográfica como um braço do próprio comitê e disponibilizar ferramentas científicas que pudessem auxiliar no processo de diagnóstico prognóstico e acompanhamento das metas intermediárias e final Para a modelagem da qualidade de água do Rio Pacoti utilizou-se o modelo QUAL-UFMG o qual foi calibrado e validado a partir de dados de monitoramento de OD DBO Fósforo e Coliformes Termotolerantes em seções de controle Para a modelagem da qualidade de água no açude Acarape do Meio um inovador modelo denominado de QUAL-HIDROSED foi proposto com foco na simulação do parâmetro fósforo total O diagnóstico revelou que todo o trecho do Rio Pacoti com exceção da nascente e o reservatório Acarape do Meio se encontram na classe 4 Um dos mais importantes produtos desta pesquisa foi a aprovação pelo Comitê de Bacias da proposta de enquadramento para um reservatório no nordeste do Brasil em função de um volume mínimo armazenado e da máxima carga de fósforo que aporta no mesmo Recentemente esta proposta de enquadramento foi ao Conselho de Recursos Hídricos do Ceará como a primeira experiência em enquadramento de corpos d’água no nordeste brasileiro
3

MODELAGEM DO ESTADO TRÓFICO DO RESERVATÓRIO DO VACACAÍ MIRIM / VACACAI MIRIM RESERVOIR TROPHIC STATE MODELLING

Kuchinski, Vinícius 22 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The eutrophication is an environmental disorder that happens due to nutrients excess, mainly in lakes and reservoirs, from human action. This disorder causes the algal bloom, impairing the water quality, increasing the water turbidity and toxicity. This work aimed to assess the trophic state of Vacacai Mirim reservoir, located in the city of Santa Maria, southern Brazil, between 2010 and 2011, using a mathematical model for simulation and verify the water quality based on CONAMA resolution 357/2005 and on the Trophic State Index. The model used in this work is denominated CE-QUAL-W2 and was developed to water quality simulation in rivers and, principally in reservoirs. Data and information for the study area that have been published in previous work were used. These data were entered in the model as input data and then made the calibration of it. The calibration was made manually, using perturbation of parameters and has proven adequate, verifying the accuracy by the average absolute error and root mean square error. After calibration, the validation was made using a data set that was not entered as input data in calibration process. Afterwards, it was proposed extreme scenarios to verify the behavior of reservoir in front of situations of drought (30 days in length), high volume of precipitation (20x and 50x increase in rainfall volume), population growth (increase in nutrients concentration at 33, 66 and 99%) and finally, a possible treatment of effluents in the drainage basin (reduction in nutrients concentration at 33, 66 and 99%). The simulation of scenarios has shown that a drought of 30 days worsens the water quality, making the reservoir hypereutrophic and harming the classification of reservoir in reference values of Class 3 from CONAMA resolution 357/2005. The increase of precipitation dilutes nutrients and pollutants, decreasing their concentration, improving the water quality and keeping the trophic state of the reservoir. The scenario of the increase of pollutant load evidences that total phosphorous and chlorophyll-a exceeds limits reference values of Class 3, being necessary attention, because they raise the trophic state of the reservoir to hypereutrophic. The effluent discharge reduction scenario shows that, by reducing 66% the launch, there are considerable water quality gains, classifying the reservoir in Class 3 and being classified as mesotrophic. / A eutrofização é um distúrbio ambiental que acontece devido ao excesso de nutrientes, principalmente em lagos e reservatórios, proveniente da ação antrópica. Esse distúrbio causa a proliferação de algas, prejudicando a qualidade da água, aumentando os níveis de turbidez e também de toxicidade da água. Assim, este trabalho teve como objetivo avaliar o estado de trofia do reservatório do rio Vacacaí Mirim, na cidade de Santa Maria/RS, entre os anos de 2010 e 2011 utilizando um modelo matemático de simulação e verificar a qualidade da água frente a resolução CONAMA 357/2005 e o Índice de Estado Trófico. O modelo utilizado neste trabalho é denominado CE-QUAL-W2 e foi desenvolvido para simulações de qualidade da água em rios e, principalmente, em reservatórios. Foram utilizados dados e informações referentes a área de estudo, que foram publicados em trabalhos anteriores. Esses dados foram inseridos no modelo como dados de entrada, para então ser feita a calibração do mesmo. A calibração foi realizada de forma manual, utilizando a perturbação de parâmetros e se mostrou adequada, ao se verificar a precisão por meio de erro médio absoluto e da raiz do erro médio quadrático. Após o modelo calibrado, foi feita a validação utilizando uma campanha que havia ficado de fora da calibração. Posteriormente, foram propostos cenários extremos para se verificar o comportamento do reservatório frente situações de estiagem, de volumes intensos precipitados, do aumento populacional e, por último, de um possível tratamento dos efluentes na bacia de drenagem. A simulação de cenários mostrou que uma estiagem de 30 dias piora a qualidade da água, tornando o reservatório hipereutrófico e prejudicando a classificação do reservatório nos valores de referência da Classe 3. O aumento da precipitação dilui nutrientes e poluentes, fazendo com que a sua concentração diminua, melhorando a qualidade da água e mantendo o estado de trofia do reservatório. O cenário de aumento da carga poluidora evidencia que o fósforo total e a clorofila a excedem os valores de referência da Classe 3, sendo necessário uma atenção maior, visto que elevam o estado trófico do reservatório para hipereutrófico. O cenário de redução do lançamento de efluentes mostra que, ao se reduzir em 66% o lançamento, há consideráveis ganhos de qualidade da água, classificando o reservatório nos valores de referência da Classe 3 e sendo classificado como mesotrófico.
4

Assessing Water Quality Modeling in Subtropical Regions Based on a Case Study of the Aguamilpa Reservoir

Obregon, Oliver 03 December 2008 (has links) (PDF)
The shortage of water in Mexico has made public and private institutions look at reservoirs as an alternative solution for present and future water supply. However, eighty percent of the existing reservoirs in Mexico are contaminated at some level, many severely. Water quality models are water-management tools used to diagnose water quality problems and the impact of various environmental conditions. They can be effective in assessing various measures of remediation leading to improved water quality. In most of the cases such water quality models have been successfully applied in reservoirs located in temperate climates. However, the use of water quality models in subtropical reservoirs, especially those in developing countries, have relatively little application because either basic data are not available or because they are not sufficient. In this study, a preliminary water quality model was developed for a subtropical reservoir to assess both the ability to collect adequate data and the model's underlying applicability in a subtropical region. The Aguamilpa reservoir is located in the western part of Mexico (Nayarit). It was built for power generation, irrigation and as a fishery. CE-QUAL-W2 is a two-dimensional hydrodynamic and water quality model suitable for long and narrow water bodies. Geometrically the Aguamilpa reservoir is long and deep, making it an ideal candidate to be modeled by CE-QUAL-W2. The model was developed for 1995 and 1996 because of a wider availability of historical data during this period. In addition to a preliminary model and assessment of applicability in this subtropical region, a monitoring and data acquisition plan was designed to identify the minimum required data which must be used to update, calibrate and simulate the water quality parameters. Once the model is calibrated, it may be used to simulate the water quality changes occurring with respect to environmental, climatological and anthropogenic effects. Further, the model may be used to prescribe operating procedures upstream as well as at the dam which can serve to improve the overall water quality. The development of the model at Aguamilpa can serve as a guideline for developing similar water quality models in this and other similar subtropical locations.
5

Service Quality Dimensions in an Online Context : -A Perspective Comparison of Service Recovery

Persson, Josefine, Claesson, Amelie January 2012 (has links)
Service quality and service recovery has been found to play a significant role in customer satisfaction and future purchase intentions. Many studies have been conducted on how to manage either the company perspective or customer perspective of these two concepts. Using the findings from five qualitative company interviews and three customer focus groups, this study addresses the purpose “to identify similarities and differences between the company and customer perspectives of service recovery in a quality system online”. The research identifies how companies in the service industry work with their websites and customer service as a tool for service quality and recovery. The company perspective is then compared to identified customer preferences in order to find similarities and differences that needs to be improved. The qualitative surveys are based on six dimensions of two existing models for service quality and service recovery online and the findings show similarities in all six dimensions, as well as several differences.
6

Servicekvalitet för e-handel inom konfektion / Quality of Service for e-commerce

Johansson, Sara, Johansson, Frida January 2012 (has links)
I och med Internets utveckling och utbredning har fler och fler företag tagit steget in i e-handelsvärlden samtidigt som fler och fler konsumenter har börjat handla via internet. För att bli framgångsrik inom detta område krävs inte bara att man har en eftertraktad produkt utan också att den service som omgärdar produkten uppfyller de förväntningar kunderna har.I denna rapport kommer vi att undersöka vilka faktorer som påverkar konsumenternas uppfattning om ett e-handelsföretags nivå av servicekvalitet, vilka krav och önskningar en sittande målgrupp har på dessa faktorer samt hur väl ett urval webbaserade butiker uppfyller dessa krav och önskemål.Genom att gå igenom teorier berörande nischmarknader och därefter gå över till att se vad det är som gör att ett företag lyckas med e-handel, kan vi se vilka faktorer som är viktiga att ta hänsyn till. Vi granskar komponenter så som användarvänligheten och komforten i att använda sig av e-handel, kundanpassning, information kring företag och produkter, säkerhetsfrågor och känslan av trygghet vid köp och kommunikationen både mellan konsumenter och kund och företag. Ytterligare kommer vi titta på hur en hemsidas utseende påverkar köpupplevelsen och känslan av trygghet.Därefter blir det en granskning av hur företag idag arbetar med dessa aspekter, där vi tittat både på företag som vänder sig till en sittande målgrupp och de som vänder sig till icke funktionshindrade för att se skillnader och möjligheter för ett företag som arbetar mot sittande. Här ser vi dock att alla företag försöker arbeta utefter de aspekter vi lagt in i teorin, men de uppfyller de krav som ställs olika. Vi ser att de företag som arbetar mot en sittande målgrupp oftast inte arbetar lika väl med de faktorer som bygger upp en fungerande och framgångsrik e-handel.För att se vad vårt företags målgrupp anser är de viktiga faktorerna, och inte bara vad teorin säger genomförde vi en enkätundersökning som bekräftade att de faktorer teorin berör även är de krav som ställs av sittande. Dock kan vi se att önskningarna på vilka servicetjänster som ska ingå ibland är högre än vad som skrivits, exempelvis finns det önskningar på att få varorna hemkörda och att även returerna ska plockas upp vid dörren. Vi ser att de företag som har en sittande målgrupp bör arbeta betydligt mer med utformningen av sin hemsida, utöka beskrivningen av plaggen och använda sig av mer informativa bilder på plaggen för att möta kundernas krav. Någonting som i dag görs av de granskade e-handelföretag som riktar sig mot en icke funktionshindrad målgrupp.Vi ser alltså att företagen behöver anpassa inte bara sina produkter utefter sin målgrupp utan även de kringtjänster de arbetar med för att möta sina kunders krav och önskemål. Det är således av stor vikt att beakta de faktorer vi i denna rapport beskrivit för att uppnå en väl fungerande e-handel.Vidare önskar vi mer forskning på vissa delar utav e-handel, exempelvis hur man i mindre företag kan arbeta för att implementera kundernas önskningar på ett effektivt sätt som är ekonomiskt hållbart.In this article we will investigate the factors affecting the costumers’ opinions about service quality among e-commerce. We will particularly investigate the demands a wheelchair bound has on these factors and study how a selection of online retailer meets these demands. This we have done by reading articles and studies on niche markets. And after that we have studied which factors making it possible for a company to succeed in e-commerce, what things an online retailer should consider as most important. Here we have found and looked at components such as user-friendliness, comfort, customization, information, security and the sense of security, communication and aesthetics.When we had enough information we stared to investigate how companies are working with service quality at the moment, both those whom have a target group that are wheelchair bound and those whom are working with a target group that has no disabilities. This we have done to see if there are any differences in their work. In these studies we found that most companies are trying to work with the factors we discussed in the theory, even though the level of their reach is very different. We have found that those companies working towards a non-disabled target group has reach further than those with a target group using wheelchairs.Even though the theory support these thought of important factors we decided to try if our target group (wheelchair bound) think the same. Bu using a questionnaire we asked a few from our target group about this and they supported our theories. Sometimes their demands on the service quality factors were even higher than we thought, for example they requested their products to be delivered to their homes and the returns to be picked at their doors. What we can see the companies working towards a wheelchair bound target group should work furthermore with their websites and use better product information than they are nowadays.So from what we can see the companies working towards wheelchair users should use these service quality factors in a better way and should try to meet their customers’ demands even better. / Program: Textilekonomutbildningen
7

三分類Qual VAR模型-美國景氣預測之應用

蔡郁敏, Tsai,Yu-Min Unknown Date (has links)
追求長期穩定的經濟成長是每個國家欲追求的目標,在經濟發展過程中,外在衝擊常常導致經濟體系的景氣循環波動,而短期間景氣循環的大幅波動將不利於經濟體系穩定發展,因為民眾的消費、廠商的投資決策以及政府政策的規劃與實施,都深深受到景氣變動的影響。因此準確預測景氣動向,深受經濟學者、政府以及一般民眾的重視。 預估景氣循環擴張和衰退持續期間的長短並不容易,由美國國家經濟研究局 提供的資料得知,第二次世界大戰後,美國景氣擴張最長的時間,曾經延續了一百零六個月,而最短的則只有十二個月;在景氣衰退方面,最短是六個月,最長則為十六個月。而二次大戰前,時間變化的幅度就更大了。由於景氣變化前的徵兆並不是很顯著,因此許多經濟學者從各種方面來探討與分析景氣循環。 本篇論文引用 ordered Probit 模型對 Dueker (2005) 文章作一個擴展與應用,將Dueker文中原本的二分類:景氣衰退、景氣擴張延伸為景氣三分類:景氣衰退、景氣狀態不明與景氣擴張,帶入 Qual VAR 模型並利用Gibbs sampling模擬未知參數與變數,藉由統計分析,希望能對景氣循環提出一個更為詳細的詮釋。而本篇論文的目的希望在相對於二分類模型,在總體現象上能提供一個更為完善與更明確的描述,使得在分析上能更完整。參考 NBER 所公佈的景氣轉折點並輔以其他指標,將景氣區分為三分類,以 Qual VAR 模型模擬出景氣三分類的景氣指標,再對這個指標做預測分析,並比較美國景氣在二分類與三分類之下的異同。結果指出三分類模型成功的預測出 2002 年第一季到 2003 年第三季美國景氣擴張的狀態,而三選擇模型的模型比起二選擇模型,對於預測景氣狀態有更為明確的判斷,且加入一分類指標,提供新的景氣變動解釋,幫助人們做出更為合適的決策。
8

Ověření použitelnosti modelu CE-QUAL-W2 pro simulaci růstu fytoplanktonu, epifytonu a makrofyt v nádrži Lipno / Verification of Applicability of the CE-QUAL-W2 Model for Simulation of Phytoplankton, Epiphyton and Macrophyte Growth in Lipno Reservoir

ŠÁMALOVÁ, Klára January 2008 (has links)
Verification of applicability of the CE-QUAL-W2 model for simulation of phytoplankton, epiphyton and macrophyte growth in Lipno Reservoir was tested. The model was first calibrated for the year 2004, then was applicated to the whole investigated period from 1.1. 2000 to 31.12. 2005. Sensitivity analysis was executed for mean growth parameters of phytoplankton, periphyton and macrophytes.
9

Quality modeling of Poti River water / Modelagem da qualidade da Ãgua do Rio Poti

Antonio Alves de Oliveira Filho 28 November 2014 (has links)
nÃo hà / The disorderly growth of the capital of PiauÃ, marked mainly by housing occupancy on the banks of river Poti and the existence of clandestine connections of raw sewage in rainwater drainage pipes, has contributed significantly to the pollution of the waters of the river basin of the ParnaÃba River (semiarid region Brazil). This research consists of making water quality measuring campaigns in Poti river and sewage released that, via gallery rainwater, focusing on a river stretch of 36.8 km long, located in the city of Teresina / PI, as well as mathematical modeling of water quality of the river based on WHAT-UFMG platform. The research is presented as the first study involving modeling of water quality in a water body of the state of PiauÃ. Modeled components were: dissolved oxygen (DO), biochemical oxygen demand (BOD) and thermotolerant coliform (TC). The results of field measurements indicated TC parameter discontinuities with respect to CONAMA Resolution n 357/2005. The calibration of the decay coefficients for each parameter resulting in deviations between measured and modeled data of up to 20%, which shows that the QUALUFMG can be used as a basis for predicting the quality of water in rivers located in semiarid regions. The calibrated model was also compared to field data from the literature. Finally, simulations were performed for different flow scenarios (Q10, Q90 and Q7,10), with consistent results and that can be used for the management of water resources in the state of PiauÃ. / O crescimento desordenado da capital piauiense, marcado sobretudo pela ocupaÃÃo habitacional Ãs margens do rio Poti e pela existÃncia de ligaÃÃes clandestinas de esgoto bruto nas tubulaÃÃes de drenagem pluvial, tem contribuÃdo significativamente para a poluiÃÃo das Ãguas da bacia hidrogrÃfica do rio ParnaÃba (regiÃo semiÃrida do Brasil). A presente pesquisa consiste na realizaÃÃo de campanhas de mediÃÃo da qualidade da Ãgua no rio Poti e dos esgotos lanÃados no mesmo, via galeria de Ãguas pluviais, com foco em um trecho do rio de 36,8 km de extensÃo, localizado na cidade de Teresina/PI, bem como na modelagem matemÃtica da qualidade da Ãgua deste rio com base na plataforma QUAL-UFMG. A pesquisa apresenta-se como o primeiro estudo envolvendo modelagem da qualidade da Ãgua em um corpo hÃdrico do estado do PiauÃ. Os componentes modelados foram: oxigÃnio dissolvido (OD), demanda bioquÃmica de oxigÃnio (DBO) e coliformes termotolerantes (CT). Os resultados das mediÃÃes de campo indicaram desconformidades do parÃmetro CT com relaÃÃo à ResoluÃÃo CONAMA n 357/2005. A calibraÃÃo dos coeficientes de decaimento para cada parÃmetro resultou em desvios entre dados medidos e modelados de atà 20%, o que mostra que o QUAL-UFMG pode ser utilizado como base para prediÃÃo da qualidade da Ãgua em rios localizados em regiÃes semiÃridas. O modelo calibrado tambÃm foi comparado a dados de campo obtidos na literatura. Finalmente, foram realizadas simulaÃÃes para diferentes cenÃrios de vazÃo (Q10, Q90 e Q7,10), apresentando resultados coerentes e que podem ser utilizados para a gestÃo dos recursos hÃdricos do estado do PiauÃ.
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The effect of e-service quality on customer's e-satisfaction in online apparel stores : Within the Swedish context

Olofsson, Linnea, Andersson Karlström, Linn January 2022 (has links)
In recent years, e-commerce has become an essential part of the global retail framework. The retail industry has undergone an essential conversion due to the rise of the Internet and the ongoing development of digitalization. The Internet is more easily accessible with a rapid increase globally, and the number of potential online buyers is gradually increasing. This accessibility of the Internet has become evident in Sweden, which has been ranked as one of the top three most digitalizing countries among the member states of the European Union. In the year 2020, sales in e-commerce increased sharply in Sweden. It has been assessed that the change in consumer behavior has led to the increased use of e-commerce, and this continuous change will proceed in the future. Hence, the purpose of this study is to examine e-service quality in online apparel stores in Sweden using the E-S-QUAL model. In addition, this study investigates if each of the four dimensions in the E-S-QUAL model has an effect on customers’ e-satisfaction in online apparel stores. The research investigates how much each of the independent variables is affecting customers’ e-satisfaction. This will be researched using Swedish university students. The research follows a quantitative research design, and the data was based on the answers from an online questionnaire which resulted in 62 responses. Random- and snowball sampling was used to collect the data, and a survey research design was followed in the study. The data were analyzed using SPSS, where regression analysis was conducted to test the hypothesis. From the analysis, it was found that all of the four dimensions have an effect on customers’ e-satisfaction. However, the results show that the two dimensions efficiency and privacy have the highest impact on customers’ perception of e-service quality and thereby are affecting customers’ level of e-satisfaction the most.

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