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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

Bullervärderingar på bostadsmarknaden : En jämförelse mellan studenters och övriga samhällets betalningsvilja för vägtrafikbuller

Edblad, Kristoffer, Mörn, Jonathan January 2015 (has links)
Denna uppsats undersöker om studenters betalningsvilja för en vägtrafikbullerreduktion från 40 dBA till 30 dBA skiljer sig från övriga samhällets betalningsvilja för samma reduktion. Övriga samhällets betalningsvilja för vägtrafikbuller är framräknat av Trafikverket i den årliga ASEK-rapporten. Bakgrunden till denna uppsats är det förslag om en ny bullerlagstiftning som regeringen har lagt fram, vilken gör skillnad mellan studentlägenheter och andra lägenheter vad gäller tillåten vägtrafikbullernivå. Om studenters betalningsvilja för vägtrafikbuller skiljer sig från övriga samhällets kan det, utifrån den aspekten, finnas belägg för en särlagstiftning för studentbostäder. Denna uppsats använder en annan metod än Trafikverket för att få fram respondenternas betalningsvilja. Vår undersökning använder metoden Contingent Valuation (CV) och Trafikverkets beräkningar är baserade på metoden Hedonisk Priser (HP). Det finns problem med båda metoderna och dessa problem finns i viss utsträckning i både vår undersökning och den studie Trafikverkets värden är baserade på. Trafikverkets beräkningar visar att individer värderar en bullerreduktion från 40 till 30 dBA till 245,5 kr/månad och person. Vår undersökning visar att studenter värderar samma bullerreduktion till 583,5/månad och person. Vi drar därför slutsatsen att utifrån vår studie och Trafikverkets bullervärdering verkar studenter ha en högre betalningsvilja för trafikbuller än övriga samhällets, och att det därmed inte finns belägg för en särlagstiftning för studentbostäder utifrån den aspekten.
2

CSR as a customer loyalty driver : Within the energy industry / CSR as a customer loyalty driver : Within the energy industry

Hagelborg, Emelie January 2018 (has links)
The need for adaption within the business world is critical to keep up with the rapidly changing pace due to the internet. The internet, among other things, provides customers with the advantage of transparency. It is constantly becoming easier for customers to gather information about companies and their products and services and compare this in the comfort of their own home. One tool they can use are comparison sites such as prisjakt.nu. These sites are also available to compare energy providers and it is free of charge. Customers can both compare and change energy providers without any cost. Furthermore, energy is a homogeneous product which mean that, until the energy bill arrives, the customer cannot tell where the energy comes from. Therefore, to make sure that customers will not change energy providers as soon as there is a change in price, something more has to be offered to make them loyal. Loyalty is one of the most significant contemporary strategies to ensure long-term customers. To identify customer needs before the customer even realizes it themselves, companies has to be proactive. They have to actively research upcoming trends and find out if these apply to their customers before their competitors does. Several trends appear every day, however, one of them which has been slowly growing during the twenty-first century is social sustainability. Consumers are becoming more informed and engaged in what products and services they buy and what social footprint it leaves. Therefore, this thesis will study corporate social sustainability (CSR) as a possible moderating factor to customer loyalty within the energy industry. Furthermore, willingness to pay (WTP) for CSR related activities will also be researched as a moderating factor to customer loyalty. This is of interest for the energy providers since customers can feel that CSR related activities are important at the same time as they do not wish to pay for it. WTP also contributes to a more realistic result since people have a tendency to answer highly on importance of sustainability questions since it is the ”right thing to do”. The method chosen to gather data for this study, besides doing a literature review, was to send out an electronic questionnaire to several energy providers customers. The survey included demographic questions as well as several questions on how highly customers value CSR, WTP for CSR and customer loyalty which were then analyzed in SPSS. The responses were both analyzed separately for each energy provider and as a full sample. Answering the research questions and hypotheses, the result provided four main points. First, it showed that men above 64 years old with an income of 10-15.000 SEK/month had a higher WTP for CSR related activities which did not add up with the theory. It was also the opposite to the customer groups who had the highest mean score for CSR value. Second, WTP for CSR related activities and value for CSR related activities did not rate the same activity as the highest one. There was, however, overall a positive, medium or high correlation between value and WTP for the different CSR activities. Third, there was a predicting relationship between value for CSR and customer loyalty as well as between WTP for CSR and customer loyalty. However, when meerging there toghether to one moderator, there was a weak and negative affect on customer loyalty. Finally, when conducting a status analysis it is clear that there are customer needs within CSR that most energy providers do not fulfill.
3

從環境面做產品設計的選擇 / The selection of product designs from the environmental aspect

李柏瀚 Unknown Date (has links)
一、 研究問題 由於環保意識的抬頭以及相關法令的公布, 環保議題便顯的相當重要,但由於一般衡量環保的指標皆為污染值, 無法列入財務報表的評估, 於是將環保與財務結合變成為一項相當重要的課題. 而一個完整的產品發展架構,還包含著顧客的因素,從顧客的角度看,消費者願意付出的價錢,以及商品的實用率包括使用年限、使用時間、商品的各式抗性等等,都會影響到整個商品設計以及選擇的架構。因此在商品設計的流程中,公司都需要一個可以綜合分析比較的架構 二、 研究目的 過去將商品設計整合選擇的研究,多半僅有考量成本面,之後由於環保意識的抬頭,又有學者提出成本與環保的整合架構,但不是單位不統一(貨幣單位與污染指標無法綜合交叉運算)就是遺漏了從消費者面考量,以及對產品實用率的考量,而產品實用率又會影響到消費者願意付出的價錢,所以一個綜合產品生命週期成本,產品生命週期對環保衝擊的評估,產品實用率以及消費者願意付出的價錢共四個面向的考量模型,才能提供一套發展產品的綜合選擇依據 三、 研究方法 由於生命週期成本,產品生命週期對環保衝擊的評估,產品實用率以及消費者願意付出的價錢四個因素互有關連,所以本研究將提出一個綜合的選擇模型,從M.D. Bovea, R. Vidal 等學者提出的Model for the eco-design of products架構為理論基礎,延伸Kumaran D. Senthil,*, S.K. Ong, A.Y.C. Nee, Reginald B.H. Tan等學者提出的A proposed tool to integrate environmental and economical assessments of products 架構以及Giancarlo Barbiroli提出的Utilization Rate架構,將其中對環保衝擊的評估、生命週期成本、以及消費者願意付出的價錢都化為貨幣單位整合考量,發整出一套綜合模型。 四、 預期結果 本研究所提出之從環境面做產品設計之方案選擇架構,藉由文獻探討,將產品生命週期成品,產品生命週期對環保衝擊的評估,產品實用率以及消費者願意付出的價錢此四個產品選擇因素綜合考量,經由模型運算後,可得出一張總表,總表列出了可接受的產品方案,以及產品方案中獲利最大的方案,希望經由此架構的考量後,企業可以真實的使用會計單位來考量產品設計的選擇方案 / The environmental topic is more and more important because the law of environmental and more and more people think the environmental product design is important. However, the design of environmentally sound products has implications not only for the companies but also for customers and the society. From the company point of view, the key factor for producing environmentally sound products is to obtain the maximum profit with their sales. So the costs incurred by the company (internal costs) must be supported by the customer’s willingness-to-pay. The rest of environmental costs (external costs) are assumed by the society. From the society point of view, the key factor for producing environmentally sound products is to obtain a reduction on both the environmental impact and external costs. So that’s important to have equilibrium between company and society goals can be achieved by adding value for the customer. (M.D. Bovea, R. Vidal 2004) But the outcome of life cycle assessment is always in different unit such as kg, v, p.p.m. , and the outcomes cannot be combined with balance sheet or other financial report such as monetary unit. So this is an important research to combine life cycle cost and life cycle assessment. But a complete structure of product design need more factors to concern about, such as customer aspect. From the customer point of view, the product’s sustainable characteristic, resistance characteristic and other characteristics are associated with the utilization of product. And the utilization rate is affecting the customer’s wellness to pay. Not only the utilization rate affect the customer’s wellness to pay, there are other factor like the product’s look, the materials use of the product and the functionary of the product etc… So the companies need a combining structure to make comparison and make a selection of product designs. The most of past researches in product designs selection were only consider the aspect of cost. And when the new concepts of environmental product design arise, some scholars start to research the combination of life cycle cost and life cycle assessment in production design. Some of their models are using inconsistence unit, some of them are not combining the customer’s view and the utilization rate. So a combination model which includes the 1.life cycle cost, 2.life cycle assessment, 3.utlization rate and 4.customer’s wellness to pay is needed for the environmental product designs selecting.
4

Värdering av god vattenkvalitet i Brunnsviken : Effekten av närhet till vattnet på betalningsviljan

Wallström, Jenny January 2017 (has links)
För höga halter av näringsämnen och miljögifter i sjöar och vattendrag kan orsaka algblomningar, försämrat siktdjup, förändrade ekosystem, svårigheter att bada och oätlig fisk. Brunnsviken är en av de vattenförekomster som i dagsläget inte uppnår Vattenmyndighetens kriterier för god ekologisk status. För att uppnå målet krävs att åtgärder genomförs och därmed att det finns uppgifter om de kostnader och nyttor som åtgärderna leder till. I den här uppsatsen redovisas resultatet från en enkätstudie som undersöker betalningsviljan bland boende i Stockholms kommun för att genomföra åtgärder som leder till att Brunnsvikens ekologiska status går från otillfredsställande till god innan år 2027. Därutöver genomförs en regressionsanalys för att undersöka huruvida betalningsviljan är högre bland de invånarnare som bor i Brunnsvikens närområde än i övriga Stockholm. Resultatet visar att hushållen i genomsnitt är beredda att betala 465 - 552 kr årligen (i tio år) för en förbättring av vattenkvaliteten i Brunnsviken. Nuvärdet av nyttan skattas till ca 1,7 – 2 miljarder kronor, vilket kan jämföras med åtgärdskostnaderna som skattas till ca 90 miljoner kronor. Detta indikerar att åtgärderna är samhällsekonomiskt lönsamma att genomföra. Resultatet från regressionsanalysen visar att det finns ett positivt samband mellan att bo nära vattenförekomsten och viljan att betala. Däremot påverkar avståndet inte hur stort belopp respondenten är beredd att betala. Personer som anser att det är viktigt med bra fiske i Stockholms sjöar och vattendrag har både signifikant högre sannolikhet att vilja betala och är beredda att betala mer än andra.
5

Consumers' Willingness to Pay for Energy Labels on Household Appliances

Ward, David O. 01 May 2010 (has links)
Voluntary environmental labeling or certification programs provide information about the environmental characteristics of one or more aspects of a product’s life cycle to consumers. The U.S. Environmental Protection Agency and Department of Energy were among the first governmental agencies in the world to adopt environmental information programs. This study examines two U.S. programs – Energy Star, an energy efficiency labeling program, and Green Power Partnership (GPP), a green energy purchasing program, and estimates how much consumers are willing to pay for refrigerators that have been awarded these labels and what factors motivate that willingness to pay. The data were obtained from a survey conducted in March and April of 2009 via an online research panel, which was constructed to be representative of the U.S. population. Analysis of the data was conducted using conditional logit regression models with fixed parameters and mixed logit regression models with random parameters. Results revealed that consumers, on average, have a willingness to pay ranging from $237.81 to $350.54 for the Energy Star label and a willingness to pay ranging from $48.52 to $70.95 for the GPP label. The results also indicate that consumer demographics and attitudes influence WTP. In particular, individuals with greater levels of stated concern for the environment or individuals exhibiting strong perceptions on the effectiveness of consumers to affect product design and the ambient environment had a greater likelihood of choosing a labeled alternative, and thus, a greater WTP for both the Energy Star and GPP label. To manufacturers and government regulators, these results suggest that energy labels can play a significant role in a consumer’s decision making process when selecting a new appliance.
6

Consumers' Willingness to Pay for Energy Labels on Household Appliances

Ward, David O. 01 May 2010 (has links)
Voluntary environmental labeling or certification programs provide information about the environmental characteristics of one or more aspects of a product’s life cycle to consumers. The U.S. Environmental Protection Agency and Department of Energy were among the first governmental agencies in the world to adopt environmental information programs. This study examines two U.S. programs – Energy Star, an energy efficiency labeling program, and Green Power Partnership (GPP), a green energy purchasing program, and estimates how much consumers are willing to pay for refrigerators that have been awarded these labels and what factors motivate that willingness to pay. The data were obtained from a survey conducted in March and April of 2009 via an online research panel, which was constructed to be representative of the U.S. population. Analysis of the data was conducted using conditional logit regression models with fixed parameters and mixed logit regression models with random parameters. Results revealed that consumers, on average, have a willingness to pay ranging from $237.81 to $350.54 for the Energy Star label and a willingness to pay ranging from $48.52 to $70.95 for the GPP label. The results also indicate that consumer demographics and attitudes influence WTP. In particular, individuals with greater levels of stated concern for the environment or individuals exhibiting strong perceptions on the effectiveness of consumers to affect product design and the ambient environment had a greater likelihood of choosing a labeled alternative, and thus, a greater WTP for both the Energy Star and GPP label. To manufacturers and government regulators, these results suggest that energy labels can play a significant role in a consumer’s decision making process when selecting a new appliance.
7

Sistema compacto de estaçãode tratamento de água para a Sociedade Esportiva Sanjoanense / A compact station water Society for Sports Sanjoanense

Damasceno Júnior, José Edel 27 May 2011 (has links)
Made available in DSpace on 2016-05-02T13:54:13Z (GMT). No. of bitstreams: 1 JoseEdelDamascenoJunior-Dissertacao.pdf: 368451 bytes, checksum: b7c112a694f91b35a196ead761b07322 (MD5) Previous issue date: 2011-05-27 / This paper aimed at improving a water treatment plant system currently used by SABEST (Torrezan WTP). A gravity-fed WTP was updated with adaptations to solve the problems presented by the Sociedade Esportiva Sanjoanense. With such adaptations, small companies and small populations can use this modern, economic and effective technique to improve the quality of their water supply. By means of studies and reports, all the Torrezan system of a compact WTP, modified to work better, gave an excellent result for clubs and small populations to obtain a low-cost water treatment. / Procurou-se, com este trabalho, fazer melhorias em um sistema de estação de tratamento de água, utilizado pela SABESP ( ETA Torrezan),para os dias de hoje; apresentou-se uma ETA por ação gravitacional que, através de adaptações aos dias de hoje, possibilitasse que este sistema de tratamento viesse a sanar os problemas apresentados pelo clube Sociedade Esportiva Sanjoanense. Com tais adaptações, pequenas empresas e pequenas populações podem usufruir desta técnica, alcançando melhoria na qualidade da água de seu abastecimento com um método moderno, econômico e eficaz. Através de estudos e relatos, todo o sistema Torrezan de uma ETA compacta, trazendo modificações para um melhor funcionamento através de técnicas comprovadas, sem ferir as normas vigentes, conseguiu-se um excelente resultado, possibilitando que clubes e pequenas populações possam com pequeno custo ter água tratada.
8

Recebimento de lodo de ETA em ETE por lodo ativado operando com mídia plástica no tanque de aeração (MBBR). / Receiving WTP sludges in WWTP by activated sludge operating with plastic medium in the aeration tank (MBBR).

Sena, Helvécio Carvalho de 11 April 2011 (has links)
O tratamento do lodo gerado em estações de tratamento de água para abastecimento (ETAs) é uma questão a ser equacionada em todo o território nacional. O tratamento desses lodos em estações de tratamento de esgoto (ETEs) é uma alternativa a ser estudada, pois pode levar a uma solução eficaz e de custos reduzidos se compararmos aos custos de implantação e operação de um sistema de tratamento de lodos nas próprias ETAs. O recebimento de lodo de ETAs em ETEs é feito em algumas ETEs dos Estados Unidos, porém no Brasil ainda são escassos estudos específicos para sanar as questões técnicas envolvidas tanto na etapa aeróbia quanto na anaeróbia. O sistema de tratamento de esgotos por lodos ativados utilizando mídia plástica como meio suporte ao crescimento microbiológico é outro atrativo ao recebimento de lodo de ETA em uma ETE, visto que estudos demonstram que este tipo de variante é capaz de tratar maior carga orgânica, sem sofrer qualquer inibição de processo. O presente estudo avaliou o recebimento de até 400 mg de SST de lodo de ETA por litro de esgoto em um sistema utilizando mídia plástica como meio suporte. O lodo de ETA utilizado foi proveniente de sistemas que utilizaram sais de Ferro e de Alumínio em seus processos. Não foi observada qualquer inibição no processo aeróbio quanto à remoção de matéria orgânica ou nitrogenada com o recebimento de lodo de ETA em qualquer concentração e operando um sistema com mídia plástica. A carga de DBO5,20 aplicada ao reator biológico ficou entre 1,7 a 15,3 gDBO5,20/m²/dia, e a concentração média da DBO 5,20 no efluente final esteve em todo o período do experimento em 34 mg/L. Com a utilização da mídia plástica o processo de nitrificação teve taxas de remoção passando de 0,9 gNKT/m²/dia para 1,7 gNKT/m²/dia, portanto aumento de 95%. A avaliação do lodo gerado no decantador primário da ETE Piloto demonstra que houve alteração em sua composição, principalmente na relação de SV/ST e o aumento na concentração de metais, principalmente o elemento Ferro. Estas características podem levar à inibição o processo anaeróbio. O teste de Atividade Metanogênica Especifica (AME) realizada com dosagens de 0,4 g e 0,8 g de ST de lodo de ETA demonstra que há inibição da metanogênese para concentrações acima de 0,4 g de ST. A concentração na qual não se observou efeito negativo corresponde a 10% da quantidade mássica que o digestor anaeróbio foi alimentado. Porém o teste de AME reproduz toxicidade aguda, não considerando a possível adaptação que pode ocorrer ou mesmo demonstrar que um esgoto que, em primeira análise é considerado biodegradável, tem na realidade toxicidade crônica. A operação do sistema utilizando mídia plástica levou a uma redução na produção de lodo na ordem de 57%. Antes da maturação do biofilme a produção era de 0,19 g SSV/g DQO removida e passou para 0,09 g SSV/g DQO removida. / An issue to be taken into account, regarding the continental size of the country is the sludge treatment generated in water treatment plants (WTPs). The treatment of the aforementioned sludge which is held in water treatment plant (WWTP) is a valid alternative considering its costs and efficacy as opposed to the budgetary considerations for the sludge treatment in the WTPs alone. The recipience of the sludge from WTP into WWTPs, is done by some North Americans WWTPs, in Brazil, nonetheless, such specific studies are of short supply to heal the technical questions regarding both the anaerobic and also the aerobic processes. The activated sludge operational swage system with plastic medium as means to aid the microbiologic development, also entices the reception of sludge from WTP into WWTPs, given the fact that some studies have demonstrated this variant type capable of treating a much bigger organic load not even suffering any inhibition over the process. This current study evaluated the reception of a sum up to 400 mg (milligrams) of sludge TSS by sewage liter in a plastic medium as means to aid such process. The sludge from WTP used in here came from systems which utilized Iron and aluminum salt in their processes. Any inhibition regarding the removal of organic or nitrogenated matter in the aerobic process operated with the plastic medium system with the reception of sludge from WTP was observed and/or noticed The BOD5,20 charge which was applied to the biological reactor ranked between 1,7 to 15,3 gDBO5,20/m²/day, and the BOD5,20 average concentration into the final effluent was all the time the experiment was going on in 34 mg/L. Regarding the usage of plastic medium over the nitrification process, removal which jumped from 0,9 gNKT/m²/day to 1,7 gNKT/m²/day, thus an increase of 95%. The evaluation of the sludge generated from the WWTPs primary settling tank demonstrates alteration in its composition, mainly related to VS/TS and the metal concentration augmentation, iron being the most present element in here. Such characteristics may lead to an inhibition regarding the anaerobic process. The specific methanogenic activity (SMA) taking into account the dosages: 0, 4 g and 0, 8 g of TS sludge from WTP shows methanogenesis inhibition for concentrations superior to 0, 4 g of TS. 10% of mass quantity is the amount which no negative effect was noticed when feeding the anaerobic digestor. The SMA test, however, reproduces acute toxicity, not taking into account the possible adaptation that may occur or even demonstrate that the sewage which at first instance could be considered biodegradable is in its real sense chronically toxic. The activated sludge operating with plastic medium has lead the sludge production to reduction of around 57%, before the biofilm maturation the production was 0,19 g VSS/g COD removed and it was upgraded to 0,09 g VSS/g COD removed.
9

Recebimento de lodo de ETA em ETE por lodo ativado operando com mídia plástica no tanque de aeração (MBBR). / Receiving WTP sludges in WWTP by activated sludge operating with plastic medium in the aeration tank (MBBR).

Helvécio Carvalho de Sena 11 April 2011 (has links)
O tratamento do lodo gerado em estações de tratamento de água para abastecimento (ETAs) é uma questão a ser equacionada em todo o território nacional. O tratamento desses lodos em estações de tratamento de esgoto (ETEs) é uma alternativa a ser estudada, pois pode levar a uma solução eficaz e de custos reduzidos se compararmos aos custos de implantação e operação de um sistema de tratamento de lodos nas próprias ETAs. O recebimento de lodo de ETAs em ETEs é feito em algumas ETEs dos Estados Unidos, porém no Brasil ainda são escassos estudos específicos para sanar as questões técnicas envolvidas tanto na etapa aeróbia quanto na anaeróbia. O sistema de tratamento de esgotos por lodos ativados utilizando mídia plástica como meio suporte ao crescimento microbiológico é outro atrativo ao recebimento de lodo de ETA em uma ETE, visto que estudos demonstram que este tipo de variante é capaz de tratar maior carga orgânica, sem sofrer qualquer inibição de processo. O presente estudo avaliou o recebimento de até 400 mg de SST de lodo de ETA por litro de esgoto em um sistema utilizando mídia plástica como meio suporte. O lodo de ETA utilizado foi proveniente de sistemas que utilizaram sais de Ferro e de Alumínio em seus processos. Não foi observada qualquer inibição no processo aeróbio quanto à remoção de matéria orgânica ou nitrogenada com o recebimento de lodo de ETA em qualquer concentração e operando um sistema com mídia plástica. A carga de DBO5,20 aplicada ao reator biológico ficou entre 1,7 a 15,3 gDBO5,20/m²/dia, e a concentração média da DBO 5,20 no efluente final esteve em todo o período do experimento em 34 mg/L. Com a utilização da mídia plástica o processo de nitrificação teve taxas de remoção passando de 0,9 gNKT/m²/dia para 1,7 gNKT/m²/dia, portanto aumento de 95%. A avaliação do lodo gerado no decantador primário da ETE Piloto demonstra que houve alteração em sua composição, principalmente na relação de SV/ST e o aumento na concentração de metais, principalmente o elemento Ferro. Estas características podem levar à inibição o processo anaeróbio. O teste de Atividade Metanogênica Especifica (AME) realizada com dosagens de 0,4 g e 0,8 g de ST de lodo de ETA demonstra que há inibição da metanogênese para concentrações acima de 0,4 g de ST. A concentração na qual não se observou efeito negativo corresponde a 10% da quantidade mássica que o digestor anaeróbio foi alimentado. Porém o teste de AME reproduz toxicidade aguda, não considerando a possível adaptação que pode ocorrer ou mesmo demonstrar que um esgoto que, em primeira análise é considerado biodegradável, tem na realidade toxicidade crônica. A operação do sistema utilizando mídia plástica levou a uma redução na produção de lodo na ordem de 57%. Antes da maturação do biofilme a produção era de 0,19 g SSV/g DQO removida e passou para 0,09 g SSV/g DQO removida. / An issue to be taken into account, regarding the continental size of the country is the sludge treatment generated in water treatment plants (WTPs). The treatment of the aforementioned sludge which is held in water treatment plant (WWTP) is a valid alternative considering its costs and efficacy as opposed to the budgetary considerations for the sludge treatment in the WTPs alone. The recipience of the sludge from WTP into WWTPs, is done by some North Americans WWTPs, in Brazil, nonetheless, such specific studies are of short supply to heal the technical questions regarding both the anaerobic and also the aerobic processes. The activated sludge operational swage system with plastic medium as means to aid the microbiologic development, also entices the reception of sludge from WTP into WWTPs, given the fact that some studies have demonstrated this variant type capable of treating a much bigger organic load not even suffering any inhibition over the process. This current study evaluated the reception of a sum up to 400 mg (milligrams) of sludge TSS by sewage liter in a plastic medium as means to aid such process. The sludge from WTP used in here came from systems which utilized Iron and aluminum salt in their processes. Any inhibition regarding the removal of organic or nitrogenated matter in the aerobic process operated with the plastic medium system with the reception of sludge from WTP was observed and/or noticed The BOD5,20 charge which was applied to the biological reactor ranked between 1,7 to 15,3 gDBO5,20/m²/day, and the BOD5,20 average concentration into the final effluent was all the time the experiment was going on in 34 mg/L. Regarding the usage of plastic medium over the nitrification process, removal which jumped from 0,9 gNKT/m²/day to 1,7 gNKT/m²/day, thus an increase of 95%. The evaluation of the sludge generated from the WWTPs primary settling tank demonstrates alteration in its composition, mainly related to VS/TS and the metal concentration augmentation, iron being the most present element in here. Such characteristics may lead to an inhibition regarding the anaerobic process. The specific methanogenic activity (SMA) taking into account the dosages: 0, 4 g and 0, 8 g of TS sludge from WTP shows methanogenesis inhibition for concentrations superior to 0, 4 g of TS. 10% of mass quantity is the amount which no negative effect was noticed when feeding the anaerobic digestor. The SMA test, however, reproduces acute toxicity, not taking into account the possible adaptation that may occur or even demonstrate that the sewage which at first instance could be considered biodegradable is in its real sense chronically toxic. The activated sludge operating with plastic medium has lead the sludge production to reduction of around 57%, before the biofilm maturation the production was 0,19 g VSS/g COD removed and it was upgraded to 0,09 g VSS/g COD removed.
10

Contingent valuation of Yangtze finless porpoises in Poyang Lake, China

Dong, Yanyan 26 January 2011 (has links) (PDF)
Yangtze finless porpoises (YFPs) are the only fresh-water adapted porpoises in the world and they are endemic to Yangtze River system, including Poyang Lake. They are threatened by many factors, such as illegal fishing and overfishing, sand dredging, intensive shipping traffic, and pollution from agriculture and industry. Consequently, their population is decreasing at a great rate and they are listed as an endangered rare species on the red list of the International Union for Conservation of Nature (IUCN) since 1996. Moreover, a hydroelectricity project in Poyang Lake is in planning by the state of Jiangxi province, which will generate further serious threats to YFPs by cutting off their migration route and fragmenting their habitat. Therefore, it is very urgent to take some protection measures for YFPs. A special nature reserve is one possibility to protect YFPs, such as a nature reserve area, which is located in Poyang Lake. In order to find out whether a nature reserve is worthwhile, an economic analysis valuing the benefit of YFPs has been conducted. An appropriate method, the contingent valuation approach, has been chosen. The overall aim of such a contingent valuation study is to estimate the total benefits of YFPs by asking individuals’ willingness to pay for the porpoise conservation project. Because many people are unfamiliar with YFPs and the species’ total values consist of mainly non-use values, preference construction and estimating a demand function is a complex task. Therefore, the valuation workshop method, a group-based approach, which can make respondents motivated and well-informed so that they thoroughly consider the questions, provides a realistic decision-making environment. This method was selected to help respondents construct their preference. Within this study, a series of such valuation workshops were successfully organized and data and information were collected. The findings of the study have both methodological and policy-related implications. From the perspective of methodology, the important findings include: 1) Valid response rates are high enough to support further analysis and large mean WTP for porpoise conservation are obtained. Therefore, it can be concluded that the valuation workshop method as has been chosen in this study, is suitable for valuing porpoise conservation. The valuation workshop method can make people well informed about environmental goods and services, such as rare species, so that they can build their preference about them, which is quite a complex task for many individuals. IV 2) Distance effects are verified to fail to work on willingness to pay (WTP) for porpoise conservation, which is mostly driven by non-use values. Therefore, distance need not be included in the aggregation analysis of total benefits of YFPs. Similarly, the market for conservation of YFPs can be defined as the nation of China. And the sampling frame of such an evaluation of a rare species can be all the Chinese population. 3) Income effects are confirmed to be significantly influential for both Chinese respondents and German respondents. Hence, the aggregation of total values of YFPs should consider about individuals’ income levels and their ability to pay (ATP). It is inferred from the fact of smaller mean WTP in China as compared with Germany that some low-income respondents’ WTP bids are possibly distorted by their ATP, which needs further confirmation in follow-up research. In addition, there are also some policy-related implications, which are closely related with the mentioned methodological aspect: The total economic values of porpoise conservation are predicted to be appreciably huge. Definitely, their total benefits should be taken into account by politicians and decision-makers. This study makes explicit people’s attitudes and preference on the trade-off between economic growth and ecological use. The establishment of a special nature reserve for YFPs is still an open question.

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