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On systems thinking in logistics management - A critical perspectiveLindskog, Magnus January 2012 (has links)
Systems thinking. Systems theory. The systems approach. All these concepts have in various guises been claimed as central to logistics management, since its dawning in the mid twentieth century. Such claims are the starting point of this dissertation, the purpose of which is to contribute to an increased understanding of systems thinking in logistics management research, both present and for future advances. The primary unit of analysis in this dissertation is thus logistics management research. The purpose is pursued through a strategy of triangulation of research approaches, via two research objectives: To describe the nature of systems thinking in logistics management research. To explore the merits for logistics management research of an interpretive approach to actors’ systems thinking. The term systems thinking in this dissertation denotes any somewhat ‘organised’ bodies of thought with aspirations to be ‘holistic’ in the sense of aiming for comprehensiveness. This part relates mostly to the systems part of the term. With regard to the other part, systems thinking is also regarded as a term that encompasses thinking about, and in terms of, systems; either that of researchers or that of actors in logistics practices. Systems thinking can sometimes be theorised on in such a way that it seems fair to label it as systems theory. Another term that is also frequently employed is systems approach. This denotes any approach to intervene in and/or conduct research on enterprises, with a holistic ambition. Such approaches can or cannot be informed by systems theory. By approach is meant the fundamental assumptions of the effort, such as ontological and epistemological positions, views on human nature, and methodologies. This dissertation employs an approach informed by a strand of systems theory labelled Critical Systems Thinking (CST). This builds on a pluralist strategy, which entails an awareness of the strengths and weaknesses of all types of systems approaches, and thus strives towards putting them to work under such circumstances in which they are best suited. The first objective is pursued by means of a combined inductive-deductive approach presented mainly through two peer-reviewed, published journal articles. The first is an extensive literature review of academic publications in logistics management; the second is a survey of logistics management academics. Results show that the systems thinking within the discipline most often is not informed by systems theory, and is oriented towards a narrow section of the available systems approaches. This is an approach that builds on an objective world-view (realist ontology), and which seeks knowledge in terms of different kinds of law-like regularities. There are variations to the kinds of knowledge that are sought, in the sense that some search for deeper, underlying generative mechanisms (structuralist epistemology), some seek causal relationships among observable phenomena (positivist epistemology). The common view on human nature is determinist, and methodologies are often quantitative. It is concluded that logistics management employs a functionalist systems approach, which implicitly assumes homogeneity in actors’ systems thinking in mutual contexts (i.e. shared logistics practices). The second objective is pursued by adopting an interpretive systems approach, thus embracing a nominalist ontology and interpretivist epistemology, in order to explore what benefits such a perspective can lend to logistics management. Informed by the pluralist commitment of CST, theoretical constructs and methods grounded in cognitive psychology are employed to study logistics management practitioners’ systems thinking through cognitive mapping. If this reveals heterogeneities in systems thinking among actors of a mutual context, in which a high degree of homogeneity can be expected, the rationale is that the dominant homogeneity assumption is insufficient. The study, presented through an unpublished working paper, concludes that actors’ systems thinking can differ in ways that render the assumptions of the functionalist systems approach inadequate. More thought, debate, and research on an interpretive systems approach within logistics management is called for. With constant expansions in the scope of ambition for logistics management in mind – towards larger enterprise systems in the spirit of supply chain management, towards more goals for enterprises than the traditional financial ones, and towards new application areas (e.g. healthcare) – it is recognised that more and more actors become stakeholders in the practices that logistics management research seeks to incorporate within its domain of normative ambitions. This leads to an expanding scope of voices that ought to be heard in order to legitimise efforts to improve logistics management practices. This in turn motivates that we should seek to accommodate not only interpretive systems approaches, but also emancipatory, in order to ensure normative prescriptions that are legitimate from the perspectives of as many stakeholders as possible, not only from the common a priori efficiency perspectives of functionalist logistics management research.
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Systems Approach and Quantitative Decision Tools for Technology Selection in Environmentally Friendly DrillingYu, Ok Y. 16 January 2010 (has links)
One of the petroleum industry?s goals is to reduce the environmental impact of oil and gas operations in environmentally sensitive areas. To achieve this, a number of Environmentally Friendly Drilling (EFD) technologies have been developed to varying degrees. For example, the use of an elevated platform as an alternative to the gravel pad is less intrusive and leads to a more environmentally friendly approach to drilling operations. Elevated drilling platforms will require the use of piles. Another alternative to the gravel pad is the use of composite mats. Since the demand of low impact technologies for drill site construction has rapidly increased, the parametric study for the feasibility of using pile foundations and composite mats is conducted in this research.
Even though a number of EFD technologies have already been developed to varying degrees, few have been integrated into a field demonstrable drilling system (i.e., combination of technologies) compatible with ecologically sensitive areas. In general, it is difficult to select the best combination of EFD technologies for a given site because there are many possible combinations and many different evaluation criteria. The proposed technology evaluation method is based on a systems analysis that can be used for integrating current and new EFD technologies into an optimal EFD system. An optimization scheme is suggested based on a combination of multi-attribute utility theory and exhaustively enumerating all possible technology combinations to provide a quantitative rationale and suggest the best set of systems according to a set of criteria, with the relative importance of the different criteria defined by the decision-maker. In this research, the sensitivity of the optimal solution to the weight factors and the effects of the uncertainty of input scores are also discussed using a case study.
An application of the proposed approach is described by conducting a case study in Green Lake at McFaddin, TX. The main purpose of this case study is to test the proposed technology evaluation protocol in a real site and then to refine the protocol. This research describes the results of the case study which provided a more logical and comprehensive approach that maximized the economic and environmental goals of both the landowner and the oil company leaseholder.
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Goal-directed Imitation In Pre-school And Elementary School ChildrenFallahzadeh, Pardis 01 September 2011 (has links) (PDF)
Imitation is a fundamental way of acquiring knowledge in human development. In their theory of goal-directed imitation (GOADI), Wohlschlä / ger et al. (2003) divide the representation of observed movements into hierarchically organized aspects the highest of which is usually the goal. In a face-to-face imitation task young children usually copy the (spatial) goal of the body movement in terms of perceptual mirror symmetry rather than match them conceptually onto their own body, as adults do. We refer to these imitation schemes as &ldquo / mirroring&rdquo / and &ldquo / matching&rdquo / respectively. In the present study, we investigate the effects of age and perspective of the child with respect to the experimenter (0° / , 90° / , 180° / ) in two imitation tasks, a hand-to-ear and a cup-grasping task. Moreover, we
evaluate the developmental changes in the imitative behavior of children from a dynamical systems perspective. Children were supposed to imitate the movements of the experimenter. Tasks were conducted on 4.5- to 11-year-old Iranian pre-school and elementary school children (81 female, 84 male). Imitation scores for the spatial goal were analyzed in terms of mirroring or
matching. Imitation schemes varied according to age and perspective in both tasks. Overall, older children&rsquo / s imitations of movements were more adult-like as established by an adult Iranian control group than those of the younger ones. They rather matched than mirrored observed movements. In the 180° / and 90° / conditions the mirroring scheme was predominant, but in 0° / matching was predominant. GOADI was confirmed / however it was qualified by the child' / s perspective on the experimenter. Children&rsquo / s imitations showed a non-linear shift from perceptually-based mirroring to conceptually-based matching of observed movements onto their own body. This shift happens between 6 and 8-9 years of age. The amount of matching depends not only on age but also on control parameters such as spatial perspective, task demands, and exposure.
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A generative methodology for reframing visual cultureWillett, Alice A 27 November 2013 (has links)
The purpose of my experimental research in the MFA Design Program has been to develop a working methodology to transfer into a professional graphic design practice upon completion of the program. In my time here, I have built a body of work that clearly expresses my intention, and developed a solid comprehension of the field of design, its discourse, and where my work is situated within it. The intended audience for my work, which tends to fall in the blurred space between design and art, are consumers of image and pop culture in the field, gallery, and public sphere. The projects I’ll present in this report will provide a context for the process by which I arrived at a personal methodology and a narrative for how I came to think about my work up to this point. / text
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Sustainable Phosphorus Management in Sweden : A study of phosphorus recycling from wastewater sludge in several municipalities of the Östergötland CountyHaile, Henok Debessai January 2015 (has links)
The Swedish Environmental Agency (SEPA) proposed a national target to increase the rate of phosphorus recycling from wastewater sludge in 2013. Reusing phosphorus from wastewater sludge by spreading it on arable lands raises the risk of contamination and substance deposition in soils. In addition to quantifying the targeted rate of recycling, the proposal has also introduced new thresholds that limit the concentrations of undesired substances in wastewater sludge. This thesis assesses the potential challenges and opportunities in implementing the proposed measure in the Swedish municipality settings. Both qualitative and quantitative data have been gathered from three selected mid-sized Swedish municipalities in the Östergötland County and other data sources. The analytical framework of the thesis is based on the Systems Framework for Phosphorus Recovery and Reuse. Several discrepancies between the national goal to increase phosphorus recycling and local circumstances that affect local decision-making have been identified in this thesis. Reducing the flow of undesired substances into the wastewater stream raises goal conflict and is an enormous challenge which requires regulating the way chemicals are consumed in society. From the policy perspective, the national environmental objectives framework is ambiguous with regards to how local decisions should be directed in line with the national goals. The proposed measure should hierarchically be unequivocal and its implementation needs to be coordinated across all geographical scales. The thesis also highlights that there are significant local opportunities for addressing other sustainability goals through phosphorus recycling measures. Sweden’s commitment to creating a resource-efficient phosphorus cycle affirms that the key for a sustainable phosphorus management is the transformation of path-dependent social and technical systems.
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Réponses des grands lacs périalpins aux pressions anthropiques et climatiques récentes : reconstitutions spatio-temporelles à partir d'archives sédimentaires / Responses of great perialpin lakes to recent anthropogenic and climatic forcings : spatio-temporal reconstructions from sediment archivesJenny, Jean-Philippe 21 June 2013 (has links)
Les travaux de recherche développés durant cette thèse relèvent de la biogéochimie et de la sédimentologie appliquée aux systèmes lacustres. Ils s'inscrivent dans une démarche de rétro-observation sur la période récente (150-300 ans) avec l'objectif global d'évaluer l'implication des forçages environnementaux locaux (charge externe en nutriments, hydrologie) dans l'accentuation/atténuation des forçages globaux (climat). Nos recherches se sont concentrées sur une réponse intégratrice du système lacustre : le développement de l'état de l'hypoxie (manque d'oxygène ; [O2] <2µg L-1) dans les lacs, qui reflète l'état du système lacustre à l'échelle de l'hypolimnion. La thèse participe à un programme pluridisciplinaire, IPERRETRO ANR VMCS 008, dont les résultats sont utilisés dans ce travail pour comparer les trajectoires de 3 réponses biologiques (diatomées, cladocères, chironomes) et de la réponse de l'hypoxie dans les lacs du Léman, du Bourget et d'Annecy. Les objectifs spécifiques de ce travail de doctorat sont 1) de développer une méthode de quantification du régime de l'hypoxie au travers d'une approche spatio-temporelle (multi-site de carottage), 2) de caractériser les forçages et, 3) de recourir aux outils de modélisation statistique afin de comprendre les relations entre les forçages (globaux et locaux) et les réponses de l'écosystème lacustre dans un contexte de réchauffement climatique. Le prélèvement inédit de 81 carottes sédimentaires s'est révélé essentiel pour quantifier 2 forçages clés de l'hypoxie dans les 3 lacs : 1) les flux biogéniques et 2) le régime des crues. Nos principaux résultats montrent que l'enrichissement en phosphore dissous a conduit à un changement d'état de l'hypolimnion dès le milieu du XXe siècle. Désormais hypoxique, les écosystèmes de l'hypolimnion semblent particulièrement vulnérables face à l'augmentation croissante des températures. En revanche, l'action des crues (à l'échelle pluriannuelle, pluri-décennale et centennale) présente des effets bénéfiques sur les conditions de l'hypolimnion en favorisant périodiquement la recharge en oxygène, malgré l'état de stabilité global de l'hypoxie. D'autre part, les résultats montrent que le contexte hydrique local (~dimension des affluents) conditionne la vulnérabilité spécifique des lacs face aux changements globaux. Nous montrons qu'un lac comme Annecy (petit affluent) est plus vulnérable aux augmentations de température qu'un lac comme le Léman (gros affluent). Finalement, les trajectoires des réponses lacustres (flux biogéniques, diversité biologique et régime de l'hypoxie) indiquent que les réponses sont généralement plus immédiates dans l'hypolimnion face aux changements globaux et locaux que dans l'épilimnion. Cette différence de sensibilité des réponses, entre les « sous-systèmes », précise l'ampleur des défis pour la modélisation et la gestion intégrée des systèmes lacustres. / This Thesis is dedicated to the identification of issues (local and global stressors) that affected lakes physical and biogeological environment over the last 150 years through sediment-based palaeo-reconstructions. Our researches focussed on the recent development of hypoxia (i.e. low oxygen concentrations) which is a good indicator of lake ecosystem quality at the hypolimnetic scale. The aim is to reconstruct in 3 perialpin lakes (Geneva, Bourget, Annecy), with annual resolution, the evolution of 1) trophic level (Anthropic forcing), 2) flood regime (climate forcing) and 3) hypoxia (hypolimnetic response) in order to identify over time the role of human activity and climate on the lake ecosystem quality. A 4D approach is developed, using 80 sediment cores, to quantify for the first time the low oxygen dynamic and the flood regime from sediment archives. Statistical modelling is used to identify the relation between thermal, hydrological, trophic forcings on the response of hypoxia. 3D modelling is developed to support the results and to make results more understandable to actors of management. The principal findings gather around three topics: 1) Optimisation of spatio-temporal approach to quantify palaeoreconstruction from sediment archives based on volume calculation. Those reconstructions of hypoxia dynamic for the three lakes enable to emphasis the notion of weaken equilibrium, ecosystems vulnerability and the amplification of response following cumulative pressures. 2) New description of hypolimnetic functioning under constant increase of external pressures (with a focus on the nature of transitions between states: threshold effect, saturation effect, hypersteresis). 3) The contribution of palaeoreconstructions and statistical analyses to describe the respective influence of human activity and climate involved on the initiation of lake dysfunction, maintain or rebalancing of hypolimnetic functioning.
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Comparison of Client Attendance, Attrition, and Outcomes in 2 Class System Packages.Berends, Valori 08 1900 (has links)
Using the principles of systems analysis as a guide, this study compared two class schedule formats used by Behavior Management and Parenting Services (BMAPS) in order to address the following research questions: 1) What effects do 2 different class formats have on student attrition and appointment keeping? 2) What effects do 2 different class formats have on student outcomes on a pre and posttest assessment? 3) What effects do 2 different class formats have on staff procedures? BMAPS provides parent education to individuals referred by Child Protective Services. The current research included approximately 200 referred clients with an appointment or class scheduled with BMAPS between January 1, 2006 and September 22, 2007. Data was collected by reviewing client files for class attendance and performance records. Results of this study allow BMAPS to enlist the class format that is correlated with better attrition rates and client outcomes.
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Systémový přístup ke stanovení výše škody na životním prostředí při transportu nebezpečných chemických látek / Systems approach to determining the environmental damage during the transport of hazardous chemical substancesPopelová, Barbora January 2017 (has links)
Current status of the environmental damage amount determination is mainly focused on the long-term consequences of negative factors, such as transport and industry emissions. Significant damages however, could be caused as a result of short-term effects, such as events with leakage of the hazardous chemicals. These situations are caused by accidents during the hazardous substances transportation, when the material is leaked as a result of faults on the vehicle or during a traffic accident. Damages that are subsequently being dealt with, in most cases reflect only the costs associated with the liquidation and remediation of the affected area. However it is important to note that since the inception of the damage until the return of the environment to its original state, if at all possible, there are many changes increasing other related costs associated with their solving. An example is the inability to use the functions that the damaged area provided. The aim of the thesis was therefore thoroughly analyze the current state of determining the amount of damage to the environment, to analyze appropriate methods for the unification process in the framework of expert activities and propose a systematic approach to improve the determination. The proposed procedure was subsequently implemented in a software tool that should be available for the needs of experts.
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Emancipation Through Participation: A Case StudySpies, Van Zyl January 2020 (has links)
Over the past few decades there has been a concerted effort in southern Africa forcommunity based natural resource management (CBNRM) programs. The generalpremise behind CBNRM allows local communities to be empowered to utilize theirsurrounding natural resources to facilitate socio-economic growth. This is seen as aneffective rural development tool which often takes on the form of eco-tourism inSouth Africa. It creates a link between nature conservation and socio-economicdevelopment needs and is normally built on existing conservation areas such asnational parks (Ezeuduji et al. 2017: 225).“Protected area outreach” is a form ofCBNRM (Chevallier 2016: 6), and this degree project examines how stakeholderparticipation was incorporated into the formulation of Kruger National Park’s (KNP)ten-year management plan. Using KNP’s stakeholder engagement process as anaturalistic case study, the aim is to discover the extent of participation and whethertrue empowerment is facilitated. This was done via document analysis of the 2018KNP Stakeholder Participation Report using the emancipatory approach. Thisapproach is influenced by critical, post-colonial and intersectional theory andemphasizes the attainment of social justice through the unveiling and dismantling ofinvisible oppressive power structures (Wesp et al. 2018: 319). The analysis showsthat KNP uses a systems approach to their stakeholder engagement as opposed toan empowerment one; that participation is limited to consultation and is thereforemerely a form of tokenism; that weaker marginalized stakeholder groups suffer fromsystemic exclusion and underrepresentation; and that there is little to no attentiongiven to empowerment nor structural reform to drive social change.
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A Systems Approach To Sustainable Energy Portfolio DevelopmentHadian, Saeed 01 January 2013 (has links)
Adequate energy supply has become one of the vital components of human development and economic growth of nations. In fact, major components of the global economy such as transportation services, communications, industrial processes, and construction activities are dependent on adequate energy resources. Even mining and extraction of energy resources, including harnessing the forces of nature to produce energy, are dependent on accessibility of sufficient energy in the appropriate form at the desired location. Therefore, energy resource planning and management to provide appropriate energy in terms of both quantity and quality has become a priority at the global level. The increasing demand for energy due to growing population, higher living standards, and economic development magnifies the importance of reliable energy plans. In addition, the uneven distribution of traditional fossil fuel energy sources on the Earth and the resulting political and economic interactions are other sources of complexity within energy planning. The competition over fossil fuels that exists due to gradual depletion of such sources and the tremendous thirst of current global economic operations for these sources, as well as the sensitivity of fossil fuel supplies and prices to global conditions, all add to the complexity of effective energy planning. In addition to diversification of fossil fuel supply sources as a means of increasing national energy security, many governments are investing in non-fossil fuels, especially renewable energy sources, to combat the risks associated with adequate energy supply. Moreover, increasing the number of energy sources also adds further complication to energy planning. Global warming, resulting from concentration of greenhouse gas emissions in the atmosphere, influences energy infrastructure investments and operations management as a result of international treaty iv obligations and other regulations requiring that emissions be cut to sustainable levels. Burning fossil fuel, as one of the substantial driving factors of global warming and energy insecurity, is mostly impacted by such policies, pushing forward the implementation of renewable energy polices. Thus, modern energy portfolios comprise a mix of renewable energy sources and fossil fuels, with an increasing share of renewables over time. Many governments have been setting renewable energy targets that mandate increasing energy production from such sources over time. Reliance on renewable energy sources certainly helps with reduction of greenhouse gas emissions while improving national energy security. However, the growing implementation of renewable energy has some limitations. Such energy technologies are not always as cheap as fossil fuel sources, mostly due to immaturity of these energy sources in most locations as well as high prices of the materials and equipment to harness the forces of nature and transform them to usable energy. In addition, despite the fact that renewable energy sources are traditionally considered to be environmentally friendly, compared to fossil fuels, they sometimes require more natural resources such as water and land to operate and produce energy. Hence, the massive production of energy from these sources may lead to water shortage, land use change, increasing food prices, and insecurity of water supplies. In other words, the energy production from renewables might be a solution to reduce greenhouse gas emissions, but it might become a source of other problems such as scarcity of natural resources. The fact that future energy mix will rely more on renewable sources is undeniable, mostly due to depletion of fossil fuel sources over time. However, the aforementioned limitations pose a challenge to general policies that encourage immediate substitution of fossil fuels with renewables to battle climate change. In fact, such limitations should be taken into account in v developing reliable energy policies that seek adequate energy supply with minimal secondary effects. Traditional energy policies have been suggesting the expansion of least cost energy options, which were mostly fossil fuels. Such sources used to be considered riskless energy options with low volatility in the absence of competitive energy markets in which various energy technologies are competing over larger market shares. Evolution of renewable energy technologies, however, complicated energy planning due to emerging risks that emanated mostly from high price volatility. Hence, energy planning began to be seen as investment problems in which the costs of energy portfolio were minimized while attempting to manage associated price risks. So, energy policies continued to rely on risky fossil fuel options and small shares of renewables with the primary goal to reduce generation costs. With emerging symptoms of climate change and the resulting consequences, the new policies accounted for the costs of carbon emissions control in addition to other costs. Such policies also encouraged the increased use of renewable energy sources. Emissions control cost is not an appropriate measure of damages because these costs are substantially less than the economic damages resulting from emissions. In addition, the effects of such policies on natural resources such as water and land is not directly taken into account. However, sustainable energy policies should be able to capture such complexities, risks, and tradeoffs within energy planning. Therefore, there is a need for adequate supply of energy while addressing issues such as global warming, energy security, economy, and environmental impacts of energy production processes. The effort in this study is to develop an energy portfolio assessment model to address the aforementioned concerns. vi This research utilized energy performance data, gathered from extensive review of articles and governmental institution reports. The energy performance values, namely carbon footprint, water footprint, land footprint, and cost of energy production were carefully selected in order to have the same basis for comparison purposes. If needed, adjustment factors were applied. In addition, the Energy Information Administration (EIA) energy projection scenarios were selected as the basis for estimating the share of the energy sources over the years until 2035. Furthermore, the resource availability in different states within the U.S. was obtained from publicly available governmental institutions that provide such statistics. Specifically, the carbon emissions magnitudes (metric tons per capita) for different states were extracted from EIA databases, states’ freshwater withdrawals (cubic meters per capita) were found from USGS databases, states’ land availability values (square kilometers) were obtained from the U.S. Census Bureau, and economic resource availability (GDP per capita) for different states were acquired from the Bureau of Economic Analysis. In this study, first, the impacts of energy production processes on global freshwater resources are investigated based on different energy projection scenarios. Considering the need for investing on energy sources with minimum environmental impacts while securing maximum efficiency, a systems approach is adopted to quantify the resource use efficiency of energy sources under sustainability indicators. The sensitivity and robustness of the resource use efficiency scores are then investigated versus existing energy performance uncertainties and varying resource availability conditions. The resource use efficiency of the energy sources is then regionalized for different resource limitation conditions in states within the U.S. Finally, a sustainable energy planning framework is developed based on Modern Portfolio Theory (MPT) vii and Post-Modern Portfolio Theory (PMPT) with consideration of the resource use efficiency measures and associated efficiency risks. In the energy-water nexus investigation, the energy sources are categorized into 10 major groups with distinct water footprint magnitudes and associated uncertainties. The global water footprint of energy production processes are then estimated for different EIA energy mix scenarios over the 2012-2035 period. The outcomes indicate that the water footprint of energy production increases by almost 50% depending on the scenario. In fact, growing energy production is not the only reason for increasing the energy related water footprint. Increasing the share of water intensive energy sources in the future energy mix is another driver of increasing global water footprint of energy in the future. The results of the energies’ water footprint analysis demonstrate the need for a policy to reduce the water use of energy generation. Furthermore, the outcomes highlight the importance of considering the secondary impacts of energy production processes besides their carbon footprint and costs. The results also have policy implications for future energy investments in order to increase the water use efficiency of energy sources per unit of energy production, especially those with significant water footprint such as hydropower and biofuels. In the next step, substantial efforts have been dedicated to evaluating the efficiency of different energy sources from resource use perspective. For this purpose, a system of systems approach is adopted to measure the resource use efficiency of energy sources in the presence of trade-offs between independent yet interacting systems (climate, water, land, economy). Hence, a stochastic multi-criteria decision making (MCDM) framework is developed to compute the resource use efficiency scores for four sustainability assessment criteria, namely carbon viii footprint, water footprint, land footprint, and cost of energy production considering existing performance uncertainties. The energy sources’ performances under aforementioned sustainability criteria are represented in ranges due to uncertainties that exist because of technological and regional variations. Such uncertainties are captured by the model based on Monte-Carlo selection of random values and are translated into stochastic resource use efficiency scores. As the notion of optimality is not unique, five MCDM methods are exploited in the model to counterbalance the bias toward definition of optimality. This analysis is performed under “no resource limitation” conditions to highlight the quality of different energy sources from a resource use perspective. The resource use efficiency is defined as a dimensionless number in scale of 0-100, with greater numbers representing a higher efficiency. The outcomes of this analysis indicate that despite increasing popularity, not all renewable energy sources are more resource use efficient than non-renewable sources. This is especially true for biofuels and different types of ethanol that demonstrate lower resource use efficiency scores compared to natural gas and nuclear energy. It is found that geothermal energy and biomass energy from miscanthus are the most and least resource use efficient energy alternatives based on the performance data available in the literature. The analysis also shows that none of the energy sources are strictly dominant or strictly dominated by other energy sources. Following the resource use efficiency analysis, sensitivity and robustness analyses are performed to determine the impacts of resource limitations and existing performance uncertainties on resource use efficiency, respectively. Sensitivity analysis indicates that geothermal energy and ethanol from sugarcane have the lowest and highest resource use efficiency sensitivity, respectively. Also, it is found that from a resource use perspective, ix concentrated solar power (CSP) and hydropower are respectively the most and least robust energy options with respect to the existing performance uncertainties in the literature. In addition to resource use efficiency analysis, sensitivity analysis and robustness analysis, of energy sources, this study also investigates the scheme of the energy production mix within a specific region with certain characteristics, resource limitations, and availabilities. In fact, different energy sources, especially renewables, vary in demand for natural resources (such as water and land), environmental impacts, geographic requirements, and type of infrastructure required for energy production. In fact, the efficiency of energy sources from a resource use perspective is dependent upon regional specifications, so the energy portfolio varies for different regions due to varying resource availability conditions. Hence, the resource use efficiency scores of different energy technologies are calculated based on the aforementioned sustainability criteria and regional resource availability and limitation conditions (emissions, water resources, land, and GDP) within different U.S. states, regardless of the feasibility of energy alternatives in each state. Sustainability measures are given varying weights based on the emissions cap, available economic resources, land, and water resources in each state, upon which the resource use efficiency of energy sources is calculated by utilizing the system of systems framework developed in the previous step. Efficiency scores are graphically illustrated on GIS-based maps for different states and different energy sources. The results indicate that for some states, fossil fuels such as coal and natural gas are as efficient as renewables like wind and solar energy technologies from resource use perspective. In other words, energy sources’ resource use efficiency is significantly sensitive to available resources and limitations in a certain location. x Moreover, energy portfolio development models have been created in order to determine the share of different energy sources of total energy production, in order to meet energy demand, maintain energy security, and address climate change with the least possible adverse impacts on the environment. In fact, the traditional “least cost” energy portfolios are outdated and should be replaced with “most efficient” ones that are not only cost-effective, but also environmentally friendly. Hence, the calculated resource use efficiency scores and associated statistical analysis outcomes for a range of renewable and nonrenewable energy sources are fed into a portfolio selection framework to choose the appropriate energy mixes associated with the risk attitudes of decision makers. For this purpose, Modern Portfolio Theory (MPT) and Post-Modern Portfolio Theory (PMPT) are both employed to illustrate how different interpretations of “risk of return” yield different energy portfolios. The results indicate that 2012 energy mix and projected world’s 2035 energy portfolio are not sustainable in terms of resource use efficiency and could be substituted with more reliable, more effective portfolios that address energy security and global warming with minimal environmental and economic impacts.
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