A linear model of consumption − produce-use-dispose − has constantly increased the pressure on the environment in recent decades. There has been a great belief that technology will solve the problem, but in many cases it is only partly contributing to the solution. For a full solution, the root causes of problems need to be identified. The drivers-pressures-state-impact-response (DPSIR) framework allows the drivers of a specific problem to be identified by structuring the causal relations between humans and the environment. A state/ impact-based approach can help identify pressures and drivers, and make what can be considered an end-of-pipe response. Rather than that mainstream approach, this thesis adopts a pressure-based driver-oriented approach, which could be considered a proactive approach to environmental resource management. In physical resource management, material flow analysis (MFA) is one of the tools used for communication and decision support for policy response on resource productivity and pollution abatement. Here, element flow analysis (EFA), a disaggre- gation of MFA for better mass balance, was applied in pollution control and resource management. The pressure-based driver-oriented approach was used to model element flows and thus identify the drivers of problems in order to improve pollution control and resource management in complex systems. In one case study, a source-storage-transport model was developed and applied in five lakes in the Stockholm region to identify the drivers of copper pollution by monitoring the state of the environment through element flow modeling linking diffuse sources and fate in the lakes. In a second case study, a system dynamics modeling approach was applied in dynamic element flow modeling of the global mobile phone product system to investigate the drivers for closing the material flow loop through a sensitivity analysis. In a third case study, causal loop diagram modeling was used for proactive resource management to identify root causes of a problem in a complex system (product systems of physical consumer goods) by qualitatively analyzing unintended environmental consequences of an improvement action. In the case study on lakes in the Stockholm region, the source-transport-storage model proved capable of predicting copper sources through monitoring the sediment copper content in the heavily copper-polluted lakes. The results also indicated how the model could help guide policy makers in controlling copper pollution. The system dynamics study proposed an eco-cycle model of the global mobile phone product system by tuning the drivers, which could lessen the pressures on resources by decreasing the resource demands for production and increasing resource recovery at product end-of- life. The causal loop diagram study showed that a broader systems approach is required to understand and identify the drivers for proactive resource management in a complex system, where improvement actions can lead to unintended consequences. / <p>QC 20150420</p>

ORWARE, an evolving systems analysis based computer model is used to assess the performance of different waste management options from a life cycle perspective. The present version of the model consists of different submodels for transport, treatment, and disposal of different types of liquid and solid wastes and recycling of materials. Flows between submodels are described by a vector of several substances of different relevance to the system. The model calculates emissions to water and air, amount of residues returned to arable land and energy flows using the tools of life cycle analysis (LCA) and substance flow analysis (SFA). In going in the direction of stringent environmental standards and policies, there is a need for maximizing energy recovery from waste for both environmental and economic benefits. Sweden has already experience of recovering energy from waste for district heating. Recovering energy not only of high value but also of higher quality from waste would be of interest. Hydrogen is one carrier of such energy. The possibility of using hydrogen from waste as a fuel in the transport sector would contribute in heading for creating a clean environment. In this thesis a new submodel for steam reforming of biogas recovered from an anaerobic digester is developed and used with other submodels within the ORWARE framework. Four scenarios representing alternative ways of energy recovery from the organic waste in Stockholm have been simulated to compare the associated energy turnover and different environmental impacts. Digestion of the organic waste and using the biogas to fuel cars is compared against steam reforming of biogas to hydrogen or thermal gasification of the waste and processing the product gases to hydrogen. In the latter two cases hydrogen produced is used in fuel cell cars. Avoided impacts of using the biogas and hydrogen are analyzed using the fourth scenario where the waste is incinerated to generate heat and electricity. Functional equivalence between scenarios is achieved by external supply of heat, electricity and petrol. While recognizing the uncertainties during modelling and simulation, it is possible to conclude that the results indicate that there is advantage of reduced environmental impact and high energy turnover in introducing the technologies of producing hydrogen from waste into the waste management system. Further and thorough investigation is recommended to come up with a sound and firm conclusion. Key words: Systems analysis, Life cycle analysis, Substance flow analysis, Waste management, Environmental impact, Steam reforming, Thermal gasification, Fuel cell vehicles, Hydrogen <img src="http://www.webforum.com/form/kthima/images/spacer.gif" /> / www.ima.kth.se

The thesis presents an analysis of the ten administrative procedural document flows, by which was developed and implemented a workflow system in the company Plzeňská teplárenská, a.s. Analysis processes are: Purchase requirement, Income invoice, Supply contract, Tender, Investment plan, Customer contract, Decommissioning of property, Travel order, New employee, Output sheet. Analysis of each process contains a description of the process with diagram circulation of documents and table with data that arise in individual steps. Analysis and reengineering of choosing processes took place on the basis of the decision of the company management. During of implementation appear number of problems resulting from the large scale of the project, from the shortcomings in the analysis, the lack of users and small support leadership, which led to the extension of the period projects to double the planned time. Currently, the system is in routine operation and brought all of the anticipated effects. An unexpected added value is auto-linking related documents in different agendas by using hyperlinks Powered by TCPDF (www.tcpdf.org)

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23183号 / 工博第4827号 / 新制||工||1754(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 酒井 伸一, 教授 田中 宏明, 准教授 平井 康宏 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

As Europe’s power production becomes increasingly reliant on intermittent renewable energy sources, uncertainties are likely to arise in power generation plans. Similarly, with the growing prevalence of electric vehicles, electric demand is also becoming more uncertain. These uncertainties in both production and demand can lead to challenges for European power systems. This thesis proposes the use of Monte-Carlo simulations to translate uncertainties in power generation and demand into uncertainties in the power grid. To integrate stochasticity in the forecasts, this thesis separates the multivariate probabilistic forecasting problem by first forecasting the marginal loads individually and probabilistically. Copula theory is then used to integrate spatial correlations and create realistic scenarios. These scenarios serve as inputs for Monte-Carlo simulations to estimate uncertainties in the power system. The methodology is tested using power injection data and the power system model of Switzerland. The results demonstrate that integrating stochasticity in forecasts improves the reliability of the power system. The proposed approach effectively models the uncertainty in both production and demand and provides valuable information for decision-making. / I takt med att Europas elproduktion blir alltmer beroende av intermittenta förnybara energikällor kommer det sannolikt att uppstå osäkerheter i planerna för elproduktion. På samma sätt blir efterfrågan på elektricitet mer osäker i takt med att elfordon blir allt vanligare. Dessa osäkerheter i både produktion och efterfrågan kan leda till utmaningar för de europeiska kraftsystemen. I denna avhandling föreslås att Monte-Carlo-simuleringar används för att omvandla osäkerheter i elproduktion och efterfrågan till osäkerheter i elnätet. För att integrera stokasticitet i prognoserna separerar denna avhandling det multivariata probabilistiska prognosproblemet genom att först individuellt och probabilistiskt prognostisera belastningar. Kopulateori används sedan för att integrera rumsliga korrelationer och skapa realistiska scenarier. Dessa scenarier tjänar som indata för Monte-Carlo-simuleringar för att uppskatta osäkerheterna i kraftsystemet. Metodiken testas med hjälp av data om inmatning av el och med hjälp av Schweiz kraftsystem. Resultaten visar att integrering av stokasticitet i prognoser förbättrar kraftsystemets tillförlitlighet. Den föreslagna metoden modellerar effektivt osäkerheten i både produktion och efterfrågan och ger värdefull information för beslutsfattandet.

Phosphorus (P) is an essential element for all life on our planet. During the past century anthropogenic consumption of P has reached critically unsustainable levels, the mining of finite phosphate rock and the dispersion of this resource could lead to resource scarcity in the future. The need to increase knowledge and understanding for the P system is an essential part of sustainable decision making. In this thesis the P balance of Sweden is characterised and quantified using material flow analysis methodology. Furthermore, the study provides a solid foundation of knowledge and understanding of the current state of P balance in Sweden. Major challenges are highlighted and further improvement potential is established for the Swedish flows of P. The major identified contributors to the Swedish P balance are the consumption of mineral fertilizers, the consumption patterns in society and the waste management. Moreover, there is a need to reduce the emissions of P to the environment in order to preserve natural state. The most effective ways of reducing the emissions are to reduce inputs to the system and improve the system efficiency through technical solutions, political tools and financial incentives. It is important to reduce emissions without shifting of burdens onto others. The anthropogenic activities in Sweden have a significant impact on the environment, this is due to Sweden importing P fertilizer that is added to the system. Nevertheless, there is a large potential for improvement of P resource management, where recycling and reuse of P is highlighted. Furthermore, Sweden has historically proven that political action and financial incentives are effective in reducing emissions. / Fosfor (P) är ett väsentligt element för allt liv på vår planet. Under det senaste århundradet har den antropogena förbrukningen av P uppnått kritiskt ohållbara nivåer, brytning av begränsade mängder fosfatmalm som finns och spridningen av denna resurs kan leda till resursbrist i framtiden. Behovet av att öka kunskapen och förståelsen för P systemet är en väsentlig del av hållbart beslutsfattande. I denna avhandling karakteriseras och kvantifieras P balansen i Sverige med hjälp av metoder för materialflödesanalys. Dessutom ger studien en stadig grund för kunskap och förståelse för det nuvarande tillståndet för fosforbalansen i Sverige. Viktiga utmaningar lyfts upp och ytterligare förbättringspotentialer fastställs för de svenska flödena av P. De viktigaste identifierade påverkningsfaktorerna till den svenska P-balansen är konsumtion av mineralgödsel, konsumtionsmönstren i samhället och avfallshanteringen. Utöver detta, finns det ett behov av att minska utsläppen av P till miljön för att bevara ett naturligt tillstånd. De mest effektiva sätten att minska utsläppen är att minska tillförseln av P till systemet och förbättra systemeffektiviteten genom tekniska lösningar, politiska verktyg och ekonomiska incitament. Det är viktigt att minska utsläppen utan att förskjuta bördorna på andra. Den antropogena verksamheten i Sverige har en betydande påverkan på miljön, detta beror på att Sverige importerar P gödsel som läggs till systemet. Ändå finns det en stor potential för förbättring av P resurshanteringen, där återvinning och återanvändning av P framlyfts. Dessutom har Sverige historiskt bevisat att politiska åtgärder och ekonomiska incitament är effektiva för att minska utsläppen.

<p>    </p> <p>Electronic waste is one of the fastest growing waste streams, spurred by their rising market and demand. However, these devices contain an array of metals that is recyclable for economic and environmental benefit through secondary manufacturing. As the turnaround rate for newer models quickens, consumers are motivated to purchase novel devices, leaving their current ones behind. Focusing on how United States (U.S.) households manage their electronics, a top-down approach stock and flow STELLA model was created to model the lifecycle of eight common electronics. Input data for the model came from a public online survey directed to U.S. household owning adults. From the model, a metallic stock and flow analysis was conducted to quantify the trends, environmental footprint, and economic value of stored devices in U.S. households and how it compares to devices being used, disposed, and recycled. The number of stored devices in the U.S. was found to be increasing annually with a stored amount of over 757 million stored individual electronic devices, nearly half of which originate from cell phones, carrying an economic value of 32.6 billion US dollars (USD) and carbon emissions of 7.6 billion kilograms (kg) from their metallic components alone for the year 2020. Most of the pollution and economic value stems from precious metals (PMs) and in a circular economy, these stored metals can have a significant impact to the environment and economy through recycled. Also, with advancing capabilities of smartphones, the metallic composition for device components of Samsung galaxy smartphones was quantified to assess their evolving metallic content. With the growing market of electronic devices, knowing the value and importance of devices currently in U.S. households is critical. This underlies the influence of sustainable design through a circular economy to push initiatives to manufacture recyclable friendly devices, expand the metal recycling industry, and motivate citizens to properly handle their stored devices. </p>

Controlling the temperature of the exhaust valves is paramount for proper functioning of engines and for the long lifespan of valve train components. The majority of the heat outflow from the valve takes place along the valve-seat-cylinder head-coolant thermal path which is significantly influenced by the thermal contact resistance (TCR) present at the valve/seat and seat/head interfaces. A test rig facility and experimental procedure were successfully developed to assess the effect of the valve/seat and seat/head interfaces on heat outflow from the valve, in particular the effects of the valve/seat interface geometry, seat insert assembly method, i.e. press or shrink fit, and seat insert metallic coating on the operating temperature of the valve. The results of tests have shown that the degree of the valve-seat geometric conformity is more significant than the thermal conductivity of the insert: for low conforming assemblies, the mean valve head temperature recorded during tests on copper-infiltrated insert seats was higher than that recorded during tests on noninfiltrated seats of higher conformance. The effect of the insert-cylinder head assembly method, i.e. shrink-fitted versus press-fitted inserts, has proved negligible: results have shown insignificant valve head temperature variations, for both tin-coated and uncoated inserts. On the other hand, coating the seat inserts with a layer of tin (20-22¿m) reduced the mean valve head temperature by approximately 15°C as measured during tests on uncoated seats. The analysis of the valve/seat and seat/head interfaces has indicated that the surface asperities of the softer metal in contact would undergo plastic deformation. Suitable thermal contact conductance (TCC) models, available in the public domain, were used to evaluate the conductance for the valve/seat and seat/cylinder head interfaces. Finally, a FE thermal model of the test rig has been developed with a view to assess the quality of the calculated TCC values for the valve/seat and seat/head interfaces. The results of the thermal analysis have shown that predicted temperatures at chosen control points agree with those measured during tests on thermometric seats with an acceptable level of accuracy, proving the effectiveness of the used TCC models.

Bakgrund: SME (små och medelstora företag) spelar en avgörande roll för ekonomisk tillväxt och sysselsättning. Trots deras betydelse möter dessa företag ofta utmaningar när de försöker få tillgång till finansiering från banker. Kreditgivningsprocessen för SME är komplex och kräver noggrann bedömning av kreditvärdighet och återbetalningsförmåga. Banker behöver ta hänsyn till företagens finansiella ställning, branschspecifika risker, karaktär och marknadstrender för att fatta informerade beslut. Förståelsen för dessa utmaningar och faktorer är avgörande för att utveckla effektiva strategier och metoder för kreditgivning till SME företag. Tidigare forskning visar att SME inte har en lika omfattande redovisningsinformation som större företag, det är därför viktigt att undersöka och förstå de specifika utmaningarna i kreditgivningsprocessen för SME-företag, så att lämpliga åtgärder kan vidtas för att underlätta tillgången till finansiering och stödja deras tillväxt.                  Syfte: Syftet med denna uppsats är att öka förståelsen kring vilken redovisningsinformation som används i kreditgivningsprocess, samt de utmaningar som banker kan stöta på i förhållande till SME redovisningsinformation när de ansöker om kredit. Studien kommer dessutom undersöka hur banker kan använda sig av alternativa metoder vid kreditbedömningsprocessen. Genom att identifiera vilka redovisningsinformationer som är mest relevanta för kreditbedömning. Detta indikerar att forskningen försöker hitta de viktigaste faktorerna som påverkar bedömningen av kreditvärdighet, vilket är avgörande för företag som söker finansiering. Studiens resultat kan bidra till en mer rättvis och effektiv kreditbedömningsprocess, vilket i sin tur underlättar tillgång till finansiering för SME företag och främjar deras tillväxt.                                                                                               Metod: Studien har genomförts med hjälp av en kvalitativ metod för att samla in det empiriska materialet och för att öka förståelse kring ämnet. Respondenterna valdes ut baserat på deras kompetenser inom kreditgivning till företag, särskilt de som innehar befattningar som kreditgivningschefer. Fyra respondenter intervjuades genom semistrukturerade intervjuer.                                                                                          Slutsats: Resultaten från studien visar att redovisningsinformationen som rapporteras i årsredovisningen i form av kassaflöde, nyckeltal, balans och resultaträkning inte är det enda som är betydelsefullt för bankerna under kreditgivningsprocessen. Bankerna är även intresserade av icke-finansiella information såsom företagets affärsplan, karaktär, marknadsföringsstrategier, produktdifferentiering, kundrelationer, konkurrenssituation och ledningens kompetens etc. Denna form av icke-finansiell information finns inte alltid i den inrapporterade årsredovisningen och därför måste bankerna samarbeta med andra aktörer för att minska den eventuella informationsasymmetrin som kan uppstå. / Background: SME:s (small and medium-sized enterprises) play a crucial role in economic growth and employment. Despite their significance, these companies often face challenges when seeking financing from banks. The credit assessment process for SMEs is complex and requires careful evaluation of creditworthiness and repayment capacity. Banks need to consider the companies' financial position, industry-specific risks, character, and market trends to make informed decisions. Understanding these challenges and factors is essential for developing effective strategies and methods for lending to SMEs. Previous research shows that SMEs do not have as extensive financial reporting information as larger companies. Therefore, it is important to investigate and understand the specific challenges in the credit assessment process for SMEs so that appropriate measures can be taken to facilitate access to financing and support their growth.                                                       Purpose: The purpose of this thesis is to enhance understanding of the accounting information used in the credit evaluation process and the challenges that banks may encounter regarding SME accounting information when applying for credit. Additionally, the study will explore how banks can utilize alternative methods in the credit assessment process. By investigating these areas, the research aims to improve the relationship between SMEs and banks by identifying the most relevant accounting information for credit evaluation and reducing information asymmetries. The findings of the study can contribute to a fairer and more efficient credit assessment process, thereby facilitating access to financing for SMEs and fostering their growth.                                                                 Method: The study has been conducted using a qualitative method to gather empirical data and enhance understanding of the subject. Respondents were selected based on their expertise in corporate lending, particularly those holding positions such as credit managers. Four respondents were interviewed through semi-structured interviews.                              Conclusion: The results of the study show that the financial information reported in the annual financial statements, such as cash flow, key ratios, balance sheet, and income statement, are not the only significant factors for banks during the credit assessment process. Banks are more interested in other non-financial information, such as the company's business plan, character, marketing strategies, product differentiation, customer relationships, competitive situation, and management competence, among others. These non-financial information may not always be available in the annual financial statements, and therefore, banks need to collaborate with other stakeholders to reduce potential information asymmetries.

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