900 resultados para holistic perpspective
Resumo:
This dissertation develops a strategic management accounting perspective of inventory routing. The thesis studies the drivers of cost efficiency gains by identifying the role of the underlying cost structure, demand, information sharing, forecasting accuracy, service levels, vehicle fleet, planning horizon and other strategic factors as well as the interaction effects among these factors with respect to performance outcomes. The task is to enhance the knowledge of the strategic situations that favor the implementation of inventory routing systems, understanding cause-and-effect relationships, linkages and gaining a holistic view of the value proposition of inventory routing. The thesis applies an exploratory case study design, which is based on normative quantitative empirical research using optimization, simulation and factor analysis. Data and results are drawn from a real world application to cash supply chains. The first research paper shows that performance gains require a common cost component and cannot be explained by simple linear or affine cost structures. Inventory management and distribution decisions become separable in the absence of a set-dependent cost structure, and neither economies of scope nor coordination problems are present in this case. The second research paper analyzes whether information sharing improves the overall forecasting accuracy. Analysis suggests that the potential for information sharing is limited to coordination of replenishments and that central information do not yield more accurate forecasts based on joint forecasting. The third research paper develops a novel formulation of the stochastic inventory routing model that accounts for minimal service levels and forecasting accuracy. The developed model allows studying the interaction of minimal service levels and forecasting accuracy with the underlying cost structure in inventory routing. Interestingly, results show that the factors minimal service level and forecasting accuracy are not statistically significant, and subsequently not relevant for the strategic decision problem to introduce inventory routing, or in other words, to effectively internalize inventory management and distribution decisions at the supplier. Consequently the main contribution of this thesis is the result that cost benefits of inventory routing are derived from the joint decision model that accounts for the underlying set-dependent cost structure rather than the level of information sharing. This result suggests that the value of information sharing of demand and inventory data is likely to be overstated in prior literature. In other words, cost benefits of inventory routing are primarily determined by the cost structure (i.e. level of fixed costs and transportation costs) rather than the level of information sharing, joint forecasting, forecasting accuracy or service levels.
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Research objectives. The Special Education Strategy, the legislative change based on it, and the change in the Finnish National Core Curriculum for Pre-primary and Basic Education build the background for this study. An improvement initiative called KELPO was founded in 2008 to implement a new three-level support system in municipalities. To support this initiative, the Network of Intensified and Special Support in the Metropolitan Area was founded in 2010. The Network consists of 22 pilot schools from four metropolitan municipalities and the Centre for Educational Assessment at the University of Helsinki that carries out the developmental assessment of the initiative. The objective of my study was to form an overall view of the functioning of the Network. The data included interviews of 20 principals of the schools belonging to the Network. The interviews were conducted by the Centre for Educational Assessment in the autumn of 2010. The research question is: What do principals speak about the networking done inside and between the municipalities? Methods. I received the data as already transcribed for my use. I researched it using a narrative research approach. As a method I used both thematic reading and classifying narratives by the holistic-content. These methods belong under the analyze of narratives. I collected the narratives from the principals under themes that arose from the data delimited by my research question. The narrative analysis materialized by writing the research story, as a new story was built by the principals stories theme by theme. The classification of the narratives by the holistic-content method was realized according to what kind of a gatekeeper s role each principal had. With a gatekeeper I here mean the intermediary role of a principal between the school and outside world. In addition, I used the analysis of interactive production of the narrative when applicable. Results and conclusions. Explicit features in the story of the Network were the principals at least partial uncertainty of the purpose of the networking, lack of time and resources, changing of initiatives, and lack of continuity. Positive narratives about ownership and empowerment could also be found. Nonetheless, many of the preconditions for success described by the school reform and school networking theories were not fulfilled. According to the collective story, there was no shared goal or purpose, and nor were the needs of autonomy, competence, and relatedness fulfilled. Three different kinds of gatekeepers were found in the data: The Exemplary ones, The Survivors and The Losers. The distinguishing factor turned out to be sharing of information at school. Based on the narratives, the schools with principals taking care of sharing information were the most active in partaking in networking.
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The concept of sustainable fashion covers not only the ecological and ethical matters in fashion and textile industries but also the cultural and social affairs, which are equally intertwined in this complex network. Sustainable fashion does not have one explicit or well-established definition; however, many researchers have discussed it from different perspectives. This study provides an overview of the principals, practices, possibilities, and challenges concerning sustainable fashion. It focuses particularly on the practical questions a designer faces. The aim of this study was to answer the following questions: What kind of outlooks and practices are included in sustainable fashion? How could the principles of sustainable fashion be integrated into designing and making clothes? The qualitative study was carried out by using the Grounded Theory method. Data consisted mainly of academic literature and communication with designers who practice sustainable fashion. In addition to these, several websites and journalistic articles were used. The data was analyzed by identifying and categorizing relevant concepts using the constant comparative method, i.e. examining the internal consistency of each category. The study established a core category, around which all other categories are integrated. The emerged concepts were organized into a model that pieces together different ideas about sustainable fashion, namely, when the principles of sustainable development are applied to fashion practices. The category named Considered Take and Return is the core of the model. It consists of various design philosophies that form the basis of design practice, and thus it relates to all other categories. It is framed by the category of Attachment and Appreciation, which reflects the importance of sentiment in design practice, for example the significance of aesthetics. The categories especially linked to fashion are Materials, Treatments of Fabrics and Production Methods. The categories closely connected with sustainable development are Saving Resources, Societal Implications, and Information Transparency. While the model depicts separate categories, the different segments are in close interaction. The objective of sustainable fashion is holistic and requires all of its sections to be taken into account.
Resumo:
Human activities extract and displace different substances and materials from the earth s crust, thus causing various environmental problems, such as climate change, acidification and eutrophication. As problems have become more complicated, more holistic measures that consider the origins and sources of pollutants have been called for. Industrial ecology is a field of science that forms a comprehensive framework for studying the interactions between the modern technological society and the environment. Industrial ecology considers humans and their technologies to be part of the natural environment, not separate from it. Industrial operations form natural systems that must also function as such within the constraints set by the biosphere. Industrial symbiosis (IS) is a central concept of industrial ecology. Industrial symbiosis studies look at the physical flows of materials and energy in local industrial systems. In an ideal IS, waste material and energy are exchanged by the actors of the system, thereby reducing the consumption of virgin material and energy inputs and the generation of waste and emissions. Companies are seen as part of the chains of suppliers and consumers that resemble those of natural ecosystems. The aim of this study was to analyse the environmental performance of an industrial symbiosis based on pulp and paper production, taking into account life cycle impacts as well. Life Cycle Assessment (LCA) is a tool for quantitatively and systematically evaluating the environmental aspects of a product, technology or service throughout its whole life cycle. Moreover, the Natural Step Sustainability Principles formed a conceptual framework for assessing the environmental performance of the case study symbiosis (Paper I). The environmental performance of the case study symbiosis was compared to four counterfactual reference scenarios in which the actors of the symbiosis operated on their own. The research methods used were process-based life cycle assessment (LCA) (Papers II and III) and hybrid LCA, which combines both process and input-output LCA (Paper IV). The results showed that the environmental impacts caused by the extraction and processing of the materials and the energy used by the symbiosis were considerable. If only the direct emissions and resource use of the symbiosis had been considered, less than half of the total environmental impacts of the system would have been taken into account. When the results were compared with the counterfactual reference scenarios, the net environmental impacts of the symbiosis were smaller than those of the reference scenarios. The reduction in environmental impacts was mainly due to changes in the way energy was produced. However, the results are sensitive to the way the reference scenarios are defined. LCA is a useful tool for assessing the overall environmental performance of industrial symbioses. It is recommended that in addition to the direct effects, the upstream impacts should be taken into account as well when assessing the environmental performance of industrial symbioses. Industrial symbiosis should be seen as part of the process of improving the environmental performance of a system. In some cases, it may be more efficient, from an environmental point of view, to focus on supply chain management instead.
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Human papillomaviruses (HPVs) are the causal agents of cervical cancer, which is the second most common cancer among women worldwide. Cellular transformation and carcinogenesis depend on the activities of viral E5, E6 and E7 proteins. Alterations in cell-cell contacts and in communication between epithelial cells take place during cervical carcinogenesis, leading to changes in cell morphology, increased cell motility and finally invasion. The aim of this thesis was to study genome-wide effects of the HPV type 16 (HPV-16) E5 protein on the expression of host cell messenger RNAs (mRNAs) and microRNAs by applying microarray technology. The results showed that the HPV-16 E5 protein alters several cellular pathways involved in cellular adhesion, motility and proliferation as well as in the extracellular matrix. The E5 protein was observed to enhance wound healing of epithelial cell monolayers by increasing cell motility in vivo. HPV-16 E5-induced alterations in the expression of cellular microRNAs and their target genes seem to favour increased proliferation and tumorigenesis. E5 was also shown to affect the expression of adherens junction proteins in HaCaT epithelial keratinocytes. In addition, a study of a membrane cytoskeletal cross-linker protein, ezrin, revealed that when activated, it localizes to adherens junctions. The results suggest that ezrin distribution to forming adherens junctions is due to Rac1 activity in epithelial cells. These studies reveal for the first time the holistic effects of HPV-16 E5 protein in promoting precancerous events in epithelial cells. The results contribute to identifyinging novel markers for cervical precancerous stages and to predicting disease behaviour.
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This study examines the diaconia work of the Finnish Evangelical Lutheran Church from the standpoint of clients. The role of diaconia work has grown since the early 1990s recession, and since it established itself as one of the actors along with other social organizations. Previous studies have described the changing role of diaconal work, especially from the standpoint of diaconia workers and co-operators. This research goes back to examine, beyond the activities of the diaconia work of everyday practices, its relations of ruling which are determining practices. The theoretical and methodological framework rises from the thinking of Dorothy E. Smith, the creator of institutional ethnography. Its origins are in feminism, Marxism, phenomenology, etnomethodology, and symbolic interactionism. However, it does not represent any school. Unlike the objectivity-based traditional sociology, institutional ethnography has its starting point in everyday life, and people s subjective experience of it. Everyday life is just a starting point, and is used to examine everyday life s experiences of hidden relations of ruling, linking people and organizations. The level of generalization is just on the relations of ruling. The research task is to examine those meanings of diaconia work which are embedded in its clients experiences. The research task is investigated with two questions: how diaconia work among its clients takes shape and what kinds of relations of ruling exist in diaconia work. The meanings of diaconia work come through an examination of the relations of ruling, which create new forms of diaconal work compared with previous studies. For the study, two kinds of data were collected: a questionnaire and ethnographic fieldwork. The first data set was collected from diaconal workers using the questionnaire. It gives background information of the diaconia work process from the standpoint of the clients. In the ethnographic study there were two phases. The first ethnographic material was collected from one local parish by observing, interviewing clients and diaconal workers and gathering documents. The number of observations was 36 customer appointments, and 29 interviews. The second ethnographic material was included as a part of the analysis, in which ruling relations in people s experiences were collected from the transcribed data. Close reading and narrative analysis are used as analysing methods. The analysis has three phases. First, the experiences are identified with close reading; the following step is to select some of the institutional processes that are shaping those experiences and are relevant for the research. At the third stage, those processes are investigated in order to describe analytically how they determine people s experience. The analysis produces another narrative about diaconia work, which provides tools for examining the diaconal work from a new perspective. Through the analysis it is possible to see diaconia as an exchange ratio, in which the exchange takes place between a client and a diaconia worker, but also more broadly with other actors, such as social workers, shop clerks, or with other parishioners. The exchange ratio is examined from the perspective of power which is embedded in the client s experiences. The analysis reveals that the most important relations of ruling are humiliation and randomness in the exchange ratio of diaconia work; valuating spirituality above the bodily being; and replacing official social work. The results give a map about the relations of ruling of diaconia work which gives tools to look at diaconia work s meanings to the clients. The hidden element of humiliation in the exchange ratio breaks the current picture of diaconia work. The ethos of the holistic encounters and empathic practices are shown to be of another kind when spirituality is preferred to the bodily being. Nevertheless, diaconia appears to be a place for a respectful encounter, especially in situations where the public sector s actors are retreating on liability or clients are in a life crisis. The collapse of the welfare state structures imposes on diaconia work tasks that have not previously belonged to it. At the local level, clients receive partners from diaconia workers in order to advocate them in the welfare system. Actions to influence the wider societal structures are not reached because of lacking resources. An awareness of the oppressive practices of diaconia work and their critical reviewing are the keys to the development of diaconia work, since there are such practices even in holistic and respectful diaconia work. While the research raises new information for the development of diaconia work, it also opens up new aspects for developing other kinds of social work by emphasizing the importance of taking people s experiences seriously. Keywords: diaconia work, institutional ethnography, Dorothy E. Smith, experience, customer, relations of ruling.
Resumo:
To protect and restore lake ecosystems under threats posed by the increasing human population, information on their ecological quality is needed. Lake sediments provide a data rich archive that allows identification of various biological components present prior to anthropogenic alterations as well as a constant record of changes. By providing a longer dimension of time than any ongoing monitoring programme, palaeolimnological methods can help in understanding natural variability and long-term ecological changes in lakes. As zooplankton have a central role in the lake food web, their remains can potentially provide versatile information on past trophic structure. However, various taphonomic processes operating in the lakes still raise questions concerning how subfossil assemblages reflect living communities. This thesis work aimed at improving the use of sedimentary zooplankton remains in the reconstruction of past zooplankton communities and the trophic structure in lakes. To quantify interspecific differences in the accumulation of remains, the subfossils of nine pelagic zooplankton taxa in annually laminated sediments were compared with monitoring results for live zooplankton in Lake Vesijärvi. This lake has a known history of eutrophication and recovery, which resulted from reduced external loading and effective fishing of plankti-benthivorous fish. The response of zooplankton assemblages to these known changes was resolved using annually laminated sediments. The generality of the responses observed in Lake Vesijärvi were further tested with a set of 31 lakes in Southern Finland, relating subfossils in surface sediments to contemporary water quality and fish density, as well as to lake morphometry. The results demonstrated differential preservation and retention of cladoceran species in the sediment. Daphnia, Diaphanosoma and Ceriodaphnia were clearly underrepresented in the sediment samples in comparison to well-preserved Bosmina species, Chydorus, Limnosida and Leptodora. For well-preserved species, the annual net accumulation rate was similar to or above the expected values, reflecting effective sediment focusing and accumulation in the deepest part of the lake. The decreased fish density and improved water quality led to subtle changes in zooplankton community composition. The abundance of Diaphanosoma and Limnosida increased after the reduction in fish density, while Ceriodaphnia and rotifers decreased. The most sensitive indicator of fish density was the mean size of Daphnia ephippia and Bosmina (E.) crassicornis ephippia and carapaces. The concentration of plant-associated species increased, reflecting expanding littoral vegetation along with increasing transparency. Several of the patterns observed in Lake Vesijärvi could also be found within the set of 31 lakes. According to this thesis work, the most useful cladoceran-based indices for nutrient status and planktivorous fish density in Finnish lakes were the relative abundances of certain pelagic taxa, and the mean size of Bosmina spp. carapaces, especially those of Bosmina (E.) cf. coregoni. The abundance of plant-associated species reflected the potential area for aquatic plants. Lake morphometry and sediment organic content, however, explained a relatively high proportion of the variance in the species data, and more studies are needed to quantify lake-specific differences in the accumulation and preservation of remains. Commonly occurring multicollinearity between environmental variables obstructs the cladoceran-based reconstruction of single environmental variables. As taphonomic factors and several direct and indirect structuring forces in lake ecosystems simultaneously affect zooplankton, the subfossil assemblages should be studied in a holistic way before making final conclusions about the trophic structure and the change in lake ecological quality.
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Although previous research has recognised adaptation as a central aspect in relationships, the adaptation of the sales process to the buying process has not been studied. Furthermore, the linking of relationship orientation as mindset with adaptation as a strategy and forming the means has not been elaborated upon in previous research. Adaptation in the context of relationships has mostly been studied in relationship marketing. In sales and sales management research, adaptation has been studied with reference to personal selling. This study focuses on adaptation of the sales process to strategically match it to the buyer’s mindset and buying process. The purpose of this study is to develop a framework for strategic adaptation of the seller’s sales process to match the buyer’s buying process in a business-to-business context to make sales processes more relationship oriented. In order to arrive at a holistic view of adaptation of the sales process during relationship initiation, both the seller and buyer are included in an extensive case analysed in the study. However, the selected perspective is primarily that of the seller, and the level focused on is that of the sales process. The epistemological perspective adopted is constructivism. The study is a qualitative one applying a retrospective case study, where the main sources of information are in-depth semi-structured interviews with key informants representing the counterparts at the seller and the buyer in the software development and telecommunications industries. The main theoretical contributions of this research involve targeting a new area in the crossroads of relationship marketing, sales and sales management, and buying and purchasing by studying adaptation in a business-to-business context from a new perspective. Primarily, this study contributes to research in sales and sales management with reference to relationship orientation and strategic sales process adaptation. This research fills three research gaps. Firstly, linking the relationship orientation mindset with adaptation as strategy. Secondly, extending adaptation in sales from adaptation in selling to strategic adaptation of the sales process. Thirdly, extending adaptation to include facilitation of adaptation. The approach applied in the study, systematic combining, is characterised by continuously moving back and forth between theory and empirical data. The framework that emerges, in which linking mindset with strategy with mindset and means forms a central aspect, includes three layers: purchasing portfolio, seller-buyer relationship orientation, and strategic sales process adaptation. Linking the three layers enables an analysis of where sales process adaptation can make a contribution. Furthermore, implications for managerial use are demonstrated, for example how sellers can avoid the ‘trap’ of ad-hoc adaptation. This includes involving the company, embracing the buyer’s purchasing portfolio, understanding the current position that the seller has in this portfolio, and possibly educating the buyer about advantages of adopting a relationship-oriented approach.
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Image fusion techniques are useful to integrate the geometric detail of a high-resolution panchromatic (PAN) image and the spectral information of a low-resolution multispectral (MSS) image, particularly important for understanding land use dynamics at larger scale (1:25000 or lower), which is required by the decision makers to adopt holistic approaches for regional planning. Fused images can extract features from source images and provide more information than one scene of MSS image. High spectral resolution aids in identification of objects more distinctly while high spatial resolution allows locating the objects more clearly. The geoinformatics technologies with an ability to provide high-spatial-spectral-resolution data helps in inventorying, mapping, monitoring and sustainable management of natural resources. Fusion module in GRDSS, taking into consideration the limitations in spatial resolution of MSS data and spectral resolution of PAN data, provide high-spatial-spectral-resolution remote sensing images required for land use mapping on regional scale. GRDSS is a freeware GIS Graphic User Interface (GUI) developed in Tcl/Tk is based on command line arguments of GRASS (Geographic Resources Analysis Support System) with the functionalities for raster analysis, vector analysis, site analysis, image processing, modeling and graphics visualization. It has the capabilities to capture, store, process, analyse, prioritize and display spatial and temporal data.
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Gottigere lake with a water spread area of about 14.98 ha is located in the Bellandur Lake catchment of the South Pennar River basin. In recent years, this lake catchment has been subjected to environmental stress mainly due to the rampant unplanned developmental activities in the catchment. The functional ability of the ecosystem is impaired due to structural changes in the ecosystem. This is evident from poor water quality, breeding of disease vectors, contamination of groundwater in the catchment, frequent flooding in the catchment due to topography alteration, decline in groundwater table, erosion in lake bed, etc. The development plans of the region (current as well as the proposed) ignore the integrated planning approaches considering all components of the ecosystem. Serious threats to the sustainability of the region due to lack of holistic approaches in aquatic resources management are land use changes (removal of vegetation cover, etc.), point and non-point sources of pollution impairing water quality, dumping of solid waste (building waste, etc.). Conservation of lake ecosystem is possible only when the physical and chemical integrity of its catchment is maintained. Alteration in the catchment either due to land use changes (leading to paved surface area from vegetation cover), alteration in topography, construction of roads in the immediate vicinity are detrimental to water yield in the catchment and hence, the sustenance of the lake. Open spaces in the form of lakes and parks aid as kidney and lung in an urban ecosystem, which maintain the health of the people residing in the locality. Identification of core buffer zones and conservation of buffer zones (500 to 1000 m from shore) is to be taken up on priority for conservation and sustainable management of Bangalore lakes. Bangalore is located over a ridge delineating four watersheds, viz. Hebbal, Koramangala, Challaghatta and Vrishabhavathi. Lakes and tanks are an integral part of natural drainage and help in retaining water during rainfall, which otherwise get drained off as flash floods. Each lake harvests rainwater from its catchment and surplus flows downstream spilling into the next lake in the chain. The topography of Bangalore has uniquely supported the creation of a large number of lakes. These lakes form chains, being a series of impoundments across streams. This emphasises the interconnectivity among Bangalore lakes, which has to be retained to prevent Bangalore from flooding or from water scarcity. The main source of replenishment of groundwater is the rainfall. The slope of the terrain allows most of the rainwater to flow as run-off. With the steep gradients available in the major valleys of Bangalore, the rainwater will flow out of the city within four to five hours. Only a small fraction of the rainwater infiltrates into the soil. The infiltration of water into the subsoil has declined with more and more buildings and paved road being constructed in the city. Thus the natural drainage of Bangalore is governed by flows from the central ridge to all lower contours and is connected with various tanks and ponds. There are no major rivers flowing in Bangalore and there is an urgent need to sustain these vital ecosystems through proper conservation and management measures. The proposed peripheral ring road connecting Hosur Road (NH 7) and Mysore Road (SH 17) at Gottigere lake falls within the buffer zone of the lake. This would alter the catchment integrity and hence water yield affecting flora, fauna and local people, and ultimately lead to the disappearance of Gottigere lake. Developmental activities in lake catchments, which has altered lake’s ecological integrity is in violation of the Indian Fisheries Act – 1857, the Indian Forest Act – 1927, Wildlife (Protection) Act – 1972, Water (Prevention and Control of Pollution) Act – 1974, Water (Prevention and Control of Pollution) Act – 1977, Forest (Conservation Act) – 1980, Environmental (Protection) Act – 1986, Wildlife (Protection) Amendment Act – 1991 and National Conservation Strategy and Policy Statement on Environment and Development – 1992. Considering 65% decline of waterbodies in Bangalore (during last three decades), decision makers should immediately take preventive measures to ensure that lake ecosystems are not affected. This report discusses the impacts due to the proposed infrastructure developmental activities in the vicinity of Gottigere tank.
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Urbanisation is the increase in the population of cities in proportion to the region's rural population. Urbanisation in India is very rapid with urban population growing at around 2.3 percent per annum. Urban sprawl refers to the dispersed development along highways or surrounding the city and in rural countryside with implications such as loss of agricultural land, open space and ecologically sensitive habitats. Sprawl is thus a pattern and pace of land use in which the rate of land consumed for urban purposes exceeds the rate of population growth resulting in an inefficient and consumptive use of land and its associated resources. This unprecedented urbanisation trend due to burgeoning population has posed serious challenges to the decision makers in the city planning and management process involving plethora of issues like infrastructure development, traffic congestion, and basic amenities (electricity, water, and sanitation), etc. In this context, to aid the decision makers in following the holistic approaches in the city and urban planning, the pattern, analysis, visualization of urban growth and its impact on natural resources has gained importance. This communication, analyses the urbanisation pattern and trends using temporal remote sensing data based on supervised learning using maximum likelihood estimation of multivariate normal density parameters and Bayesian classification approach. The technique is implemented for Greater Bangalore – one of the fastest growing city in the World, with Landsat data of 1973, 1992 and 2000, IRS LISS-3 data of 1999, 2006 and MODIS data of 2002 and 2007. The study shows that there has been a growth of 466% in urban areas of Greater Bangalore across 35 years (1973 to 2007). The study unravels the pattern of growth in Greater Bangalore and its implication on local climate and also on the natural resources, necessitating appropriate strategies for the sustainable management.
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Agroforestry has a potential for sequestering as much carbon if not more than forests. Massive benefits can be channeled to small farmers and landless labourers through cultivation of Tamarind and other fast growing and fruit yielding trees. This paper describes a project started by small farmers and landless labourers in a semiarid areas of south India. The aim is to upgrade dryland holdings of the member families through economically sound dry land horticulture, community woodlots, and planting of fast growing species along orchard and field boundaries. The small farmers invest massive labour inputs and project gives economic benefits to change their land use practices and improve environmental quality. This paper describes the planning. processes of the project, hurdles in finding AIJ partners, current monitoring procedures and costs of C sequestration. This shows this project is economically viable on its own, but initially needed, and continues to need Carbon credit investment in order to spread rapidly across the geopolitical region covered by the organization. It argues that economic gains to small farmers and landless labourers are the most certain way of achieving massive biomass increase and soil carbon replenishment, and that multiple holistic benefits are achieved through this kind of project.
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The influence of geometric parameters, such as blade profile and hub geometry on axial flow turbines for micro hydro application remains poorly characterized. This paper first introduces a holistic theoretical model for studying the hydraulic phenomenon resulting from geometric modification to the blades. It then describes modification carried out on two runner stages, of which one has untwisted blades and the other has twisted blades obtained by modifying the inlet hub. The experimental results showed that the performance of the untwisted blade runner was satisfactory with a maximum efficiency of 68%. However, positive effects of twisted blades were clearly evident with an efficiency rise of more than 2%. This study also looks into the possible limitations of the model and suggests the extension of the experimental work and the use of computational tools to conduct a progressive validation of all experimental findings, especially on the flow physics within the hub region and the slip phenomena. The paper finally underlines the importance of developing a standardization philosophy for axial flow turbines specific for micro hydro requirements. DOI:10.1061/(ASCE)EY.1943-7897.0000060. (C) 2012 American Society of Civil Engineers.
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The rapid emergence of infectious diseases calls for immediate attention to determine practical solutions for intervention strategies. To this end, it becomes necessary to obtain a holistic view of the complex hostpathogen interactome. Advances in omics and related technology have resulted in massive generation of data for the interacting systems at unprecedented levels of detail. Systems-level studies with the aid of mathematical tools contribute to a deeper understanding of biological systems, where intuitive reasoning alone does not suffice. In this review, we discuss different aspects of hostpathogen interactions (HPIs) and the available data resources and tools used to study them. We discuss in detail models of HPIs at various levels of abstraction, along with their applications and limitations. We also enlist a few case studies, which incorporate different modeling approaches, providing significant insights into disease. (c) 2013 Wiley Periodicals, Inc.
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Grain boundary dynamics and grain growth play a pivotal role in the fabrication of functional polycrystalline materials. However, not much is known about the delicate interplay between various microscopic processes that drive grain boundary motion which eventually culminates in the desired grain morphology. Colloidal systems are ideally suited to bridge the gap between the microscopic and macroscopic processes underlying grain growth, since their dynamics can be followed in real space and real time with single-particle resolution. The present review aims at highlighting contributions from colloid experiments that have led to a holistic understanding of grain growth in polycrystalline materials.