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Flow Analysis (flow + analysis)
Selected AbstractsConstruction and Evaluation of a Gold Tubular Electrode for Flow Analysis: Application to Speciation of Antimony in Water SamplesELECTROANALYSIS, Issue 6 2007Rodrigo Santos Abstract A tubular gold electrode (TGE) is described for the first time by summarizing the important aspects of its construction and evaluation. Applicability of the TGE is evaluated in the speciation of Sb(III) and Sb(V) using anodic stripping voltammetry in a single flow manifold. Studies with surface active interferences and metallic cations were performed. The proposed conditions for antimony determination showed good tolerance towards cationic, anionic and nonionic surface active substances. A linear response for antimony was obtained for solutions containing significant amounts of several metallic cations. Linear calibration curves for Sb(III) were obtained in the range 1,10,ppb with a detection limit of 0.19,ppb (CV=2.91%, n=5, [Sb(III)]=5,ppb). For Sb(V), linear calibration curves were in the range 1,15,ppb with a detection limit of 0.32,ppb (CV=1.41%, n=5, [Sb(V)]=5,ppb). The figures of merit achieved sustain for the good applicability of the proposed method as it allows the determination of antimony at levels below maximum values permitted in consuming waters. Results of antimony concentration determined in water samples were validated against the ICP-MS reference procedure or compared with reference water samples. [source] Environmental Relations and Biophysical Transition: The Case of Trinket IslandGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 4 2003Simron Jit Singh ABSTRACT To what extent is an island economy cut off from the rest of the world? Defined as a mass of land bounded by water, island societies connect and exchange with their surroundings rather intensely. Based on empirical research, this paper explores the role of a ,remote' island society on Trinket in generating or sheltering itself from the process of globalisation in which con-textually given borders are transgressed and displaced. To this end, we apply the concepts of societal metabolism and colonising natural processes operationalised by Material and Energy Flow Analysis (MEFA), and Human Appropriation of Net Primary Production (HANPP) respectively. Using these biophysical indicators, we describe the transition from a metabolism based upon the natural environment to metabolism based on exchange with other societies. Data presented in this paper further reveal a process of industrialisation and integration into the global market of a so-called ,closed' and ,inaccessible' island society. [source] Vineberg's Procedure Modified Technique: Flow Analysis, Immediate Postoperative Results and Angiographic EvaluationJOURNAL OF CARDIAC SURGERY, Issue 4 2006Ph.D.Article first published online: 29 JUN 200, Ray C.J. Chiu M.D. No abstract is available for this article. [source] Implementing the Results of Material Flow AnalysisJOURNAL OF INDUSTRIAL ECOLOGY, Issue 5 2009Challenges, Progress First page of article [source] A Product-Level Approach to Historical Material Flow AnalysisJOURNAL OF INDUSTRIAL ECOLOGY, Issue 5-6 2008Tungsten as a Case Study Summary Studies of material cycles, which have a solid history in biogeochemistry, include characterization of technological materials cycles that quantify the way in which materials move through the economy and environment of a region. One of the most important aspects of historical technological materials cycles is determining how much material goes into various uses over time and modeling its lifetime in each use. A material flow analysis methodology is presented by which a historical (i.e., 1975 to 2000) study of tungsten use in the United States was constructed. The approach utilized in this study is twofold: the traditional approach by which material going into end-use sectors is approximated (the "end-use sector model"), and a second approach by which end-use products are specifically addressed (the "finished product model"). By virtue of the latter method, a detailed historical account of a material's end uses was developed. This study shows that (1) both models present a detailed treatment of trade of finished products over time for a variety of highly disaggregated products, (2) the end-use sector model provides a method to combine quantitative and qualitative data about products in various sectors to estimate domestic production for a metal about which little is known in terms of its end uses, and (3) the finished product model produces detailed estimates of domestic production for a large number of highly disaggregated products. [source] Material Flows in a Social Context: A Vietnamese Case Study Combining the Materials Flow Analysis and Action-in-Context FrameworksJOURNAL OF INDUSTRIAL ECOLOGY, Issue 1 2007Marieke HOBBES Summary Materials flow analysis (MFA) is one of the central achievements of industrial ecology. One direction in which one can move MFA beyond mere accounting is by putting the material flows in their social context. This "socially extended MFA" may be carried out at various levels of aggregation. In this article, specific material flows will be linked to concrete actors and mechanisms that cause these flows,using the action-in-context (AiC) framework, which contains, inter alia, both proximate and indirect actors and factors. The case study site is of Tat hamlet in Vietnam, set in a landscape of paddy fields on valley floors surrounded by steep, previously forested slopes. Out of the aggregate MFA of Tat, the study focuses on material flows associated with basic needs and sustainability. The most important actors causing these material flows are farming households, politicians, traders, and agribusiness firms,of which local politicians turned out to be pivotal. The study shows the value of combining MFA with actor-based social analysis. MFA achieves the balanced quantification of the physical system, thus helping to pinpoint key processes. Actor-based analysis adds the causal understanding of what drives these key processes, leading to improved scenarios of the future and the effective identification of target groups and instruments for policy making. [source] Books: Practical Handbook of Material Flow AnalysisJOURNAL OF INDUSTRIAL ECOLOGY, Issue 1-2 2006Reinout Heijungs No abstract is available for this article. [source] Long-term Coordination of Timber Production and Consumption Using a Dynamic Material and Energy Flow AnalysisJOURNAL OF INDUSTRIAL ECOLOGY, Issue 3 2004Daniel B. Müller Summary A dynamic model for wood and energy flows is used to analyze regional timber management. The model combines a sitequality-dependent forest-growth module with modules for the timber industry, timber products use, waste management, and energy supply. The model is calibrated with data of a Swiss lowland region for the period of 1900,1997. Scenarios are developed for the period until 2100 in order to discuss possible future roles of domestic timber. Model simulations show that, with present strategies, timber overproduction will further increase in the twenty-first century because of an increase in forest site quality in the second half of the twentieth century, among other reasons. The increase in building gross floor area of the region by a factor of 5 during the twentieth century coincides with a reduction of timber use in building construction by a factor of 4.5, from 90 kg/m2 to 20 kg/m2. Increasing timber density in buildings could address overproduction; however, a strategy of timber construction could not be accomplished with domestic timber alone. A balance of production and consumption on the present level could also be achieved in a scenario in which the present building stock is gradually exchanged during the twenty-first century with buildings that exclusively use a combination of solar panels on roofs and domestic firewood and used wood as heat-energy sources. These replacement buildings would have density typical of late twentieth-century buildings, and they would need to perform on a low-energy standard of not more than 130 MJ/m2/yr. [source] Materials and Energy Flow Analysis of Paper Consumption in the United Kingdom, 1987-2010JOURNAL OF INDUSTRIAL ECOLOGY, Issue 3 2001Erik Sundin Summary This article presents the results of a life-cycle materials and energy flow analysis for the pulp and paper cycle in the United Kingdom. Material flows are reconstructed for the period be-tween 1987 and 1996 for all major processes associated with the paper cycle, and system energy requirements are calculated over this period using the best available data. Attention is drawn to the import dependence of U.K. paper demand, and the significant energy requirements associated with upstream forestry processes. The historical trend analysis is then used to model possible future developments in materials and energy consumption until 2010 under a variety of assumptions about process technology improvements, wastepaper utilization rates, and changing demand trends. The results indicate that policy options to increase recycling yield some energy benefits, but these are small by comparison with the benefits to be gained by reducing consumption of paper and improving process technology. The structure of the electricity supply industry in the United Kingdom means that global energy benefits could also be achieved by increasing the contribution from imported pulp. [source] Virtual Shop Clusters: A New Layout Concept for a Ship Repair and Maintenance FacilityNAVAL ENGINEERS JOURNAL, Issue 2 2008BRIAN MAYER Organic ship maintenance facilities and depots of the Navy are mostly organized as trade-specific shops rather than by product (or process) families. For example, welders are in the weld shop, machinists are in the machine shop, pipe-fitters are in the pipe shop, etc. There is a belief that this guild-type organizational structure is what enables a repair facility to do almost anything, albeit at the cost of moving product all over the "factory." This skill-based organizational structure is identical to the functional (or department) layout that is preferred by most jobshops in the commercial manufacturing sectors. But, any company that has successfully implemented Lean Thinking has almost always replaced a Functional (or Process Village) Layout by a Cellular Layout. At the Navy's Southeast Regional Maintenance Center (SERMC), a typical repair job must visit multiple shops that pass work back and forth between them. For example, a pipe job may be sent by the pipe shop to the machine shop for re-threading, then routed to the weld shop where it is welded to a frame, after which the welded sub-assembly returns to the pipe shop for inspection and final assembly. Thereby, significant delays and operational wastes occur because people have to walk between the shops, discuss matters at daily production meetings, and e-mail/phone each other to make sure that their schedules match. If activities are not completed as per schedule, the jobs get further delayed because they queue at the shops, waiting to be served. This lack of detailed (and accurate) planning and scheduling, combined with poor schedule visibility and shop floor control, is the curse of the Functional Layout that currently exists at SERMC. This paper will describe a pilot project to assess the feasibility of cellular manufacturing at SERMC. The fundamental hypothesis that was tested is that even in a repair and maintenance facility there could exist several families of repair jobs where jobs grouped into a family require similar combinations of processes, equipment, materials, etc. that can be provided by a small group of shops. In fact, several potential families of repair jobs, and the appropriate cluster of shops for each family of repair jobs, were identified using the Production Flow Analysis and Simplification Toolkit (PFAST) software. Based on these results, it was decided to implement a shop cluster (or focused factory, or repair cell) to complete any repair jobs done by the dive shop. It was recommended that the dive shop be merged with a few other shops, and be provided the necessary tools, cross-trained personnel, equipment, and other support systems to become an autonomous multi-function shop. Simulation using the SimCAD software from CreateAsoft Inc. (http://www.createasof.com) was used to verify the results expected from making the proposed changes. The primary analysis was intended to evaluate the benefits of implementing a focused factory in the dive shop. The secondary analysis was intended to evaluate the advantages of implementing a virtual shop cluster (or focused factory, or repair cell) in any ship repair facility like SERMC. The simulation results showed that implementing either physical cells or virtual cells based on the different families of repair jobs identified by PFAST could improve job turnaround times at any Navy ship repair facility like SERMC. Both the types of delays as well as the time values of these delays differed significantly across the existing and alternative shop configurations that were proposed. [source] Low and high flow analyses and wavelet application for characterization of the Blue Nile River systemHYDROLOGICAL PROCESSES, Issue 3 2010Assefa Melesse Abstract The low and high flow characteristic of the Blue Nile River (BNR) basin is presented. The study discusses low and high flow, flow duration curve (FDC) and trend analysis of the BNR and its major tributaries. Different probability density functions were fitted to better describe the low and high flows of the BNR and major tributaries in the basin. Wavelet analysis was used in understanding the variance and frequency-time localization and detection of dominant oscillations in rainfall and flow. FDCs were developed, and low flow (below 50% exceedance) and high flow (over 75% exceedance) of the curves were analysed and compared. The Gravity Recovery and Climate Experiment (GRACE) satellite-based maps of monthly changes in gravity converted to water equivalents from 2003 to 2006 for February, May and September showed an increase in the moisture influx in the BNR basin for the month of September, and loss of moisture in February and May. It was also shown that 2004 and 2005 were drier with less moisture influx compared to 2003 and 2006. On the basis of the Kolmogorov-Smirnov, Anderson-Darling and Chi-square tests, Gen. Pareto, Frechet 3P, Log-normal, Log-logistics, Fatigue Life and Phased Bi-Weibull distributions best describe the low and high flows within the BNR basin. This will be beneficial in developing flow hydrographs for similar ungauged watersheds within the BNR basin. The below 50% and above 75% exceedance on the FDC for five major rivers in addition to the BNR showed different characteristics depending on size, land cover, topography and other factors. The low flow frequency analysis of the BNR at Bahir Dar showed 0·55 m3/s as the monthly low flow with recurrence interval of 10 years. The wavelet analysis of the rainfall (at Bahir Dar and basin-wide) and flows at three selected stations shows inter- and intra-annual variability of rainfall and flows at various scales. Copyright © 2009 John Wiley & Sons, Ltd. [source] Progressive optimization on unstructured grids using multigrid-aided finite-difference sensitivitiesINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 10-11 2005L. A. Catalano Abstract This paper proposes an efficient and robust progressive-optimization procedure, employing cheap, flexible and easy-to-program multigrid-aided finite-differences for the computation of the sensitivity derivatives. The entire approach is combined with an upwind finite-volume method for the Euler and the Navier,Stokes equations on cell-vertex unstructured (triangular) grids, and validated versus the inverse design of an airfoil, under inviscid (subsonic and transonic) and laminar flow conditions. The methodology turns out to be robust and highly efficient, the converged design optimization being obtained in a computational time equal to that required by 11,17 (depending on the application) multigrid flow analyses on the finest grid. Copyright © 2004 John Wiley & Sons, Ltd. [source] Phasing Out Cadmium, Lead, and MercuryJOURNAL OF INDUSTRIAL ECOLOGY, Issue 1 2009Effects on Urban Stocks, Flows Summary Large stocks of metals have accumulated in the urban technosphere (i.e., the physical environment altered by human activity). To minimize health and environmental risks, attempts were begun in the 1980s to phase out the use of cadmium (Cd), lead (Pb), and mercury (Hg). To study the effect of this attempt, we conducted substance flow analyses (SFAs) in Stockholm, Sweden, in 1995 and in 2002,2003, which allow a comparison of the results over time. The SFAs showed a reduction in the stocks of Cd and Hg by approximately 25% to 30% between 1995 and 2002,2003. For Pb, the stock development was more uncertain. Cd and Hg inflow was substantially reduced during this period, but Pb inflow increased. Amounts of Cd and Pb in waste were still large, whereas Hg flows in waste were decreasing. Furthermore, although emissions of Pb decreased, Cd and Hg emissions were in the same range as in 1995. The application of SFAs has provided unique data on the accumulation of metals in the Stockholm technosphere, thus serving as a valuable indicator of how the phasing out progresses. The changes can be related to regulations, initiatives by industries and organizations, and the proactive attitude of the local environmental authorities and of the water company. [source] An Optimizing Compiler for Automatic Shader BoundingCOMPUTER GRAPHICS FORUM, Issue 4 2010Petrik Clarberg Abstract Programmable shading provides artistic control over materials and geometry, but the black box nature of shaders makes some rendering optimizations difficult to apply. In many cases, it is desirable to compute bounds of shaders in order to speed up rendering. A bounding shader can be automatically derived from the original shader by a compiler using interval analysis, but creating optimized interval arithmetic code is non-trivial. A key insight in this paper is that shaders contain metadata that can be automatically extracted by the compiler using data flow analysis. We present a number of domain-specific optimizations that make the generated code faster, while computing the same bounds as before. This enables a wider use and opens up possibilities for more efficient rendering. Our results show that on average 42,44% of the shader instructions can be eliminated for a common use case: single-sided bounding shaders used in lightcuts and importance sampling. [source] Physically-based Dye Advection for Flow VisualizationCOMPUTER GRAPHICS FORUM, Issue 3 2008Guo-Shi Li Abstract Dye advection is widely used in experimental flow analysis but has seen less use for visualization in computational fluid dynamics. One possible reason for this disconnect is the inaccuracy of the texture-based approach, which is prone to artifacts caused by numeric diffusion and mass fluctuation. In this paper, we introduce a novel 2D dye advection scheme for flow visualization based on the concept of control volume analysis typically used in computational fluid dynamics. The evolution of dye patterns in the flow field is achieved by advecting individual control volumes, which collectively cover the entire spatial domain. The local variation of dye material, represented as a piecewise quasi-parabolic function, is integrated within each control volume resulting in mass conserving transport without excessive numerical diffusion. Due to its physically based formulation, this approach is capable of conveying intricate flow structures not shown in the traditional dye advection schemes while avoiding visual artifacts. [source] Flashing characteristics in a pipe downstream from a depressurizing tank and temperature fluctuation characteristics at a mixing tee junction with cold water injectionHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 5 2003Koji Shiina Abstract The flashing characteristics in a pipe downstream from a depressurizing tank were experimentally and analytically investigated on the basis of the transient test and two-phase flow analysis. The following conclusions were obtained. (1) When the pressure margin of the pump inlet side and the distance to obtain an isothermal condition were sufficient, flashing phenomena did not occur in spite of the decreasing pressure. (2) When the ratio of the cold water injection flow rate to the hot water flow rate Mc/Mh increased, the peak distance of the water temperature fluctuation moved from L/D = 1 to 0, and the maximum water temperature fluctuation ratio was about 40% of the temperature difference between hot and cold water near the mixing tee junction. Because no problem occurred regarding the pipe material thermal fatigue, reliability of the mixing tee junction was assured. (3) Due to suppression of flashing phenomena of the mixing pipe system, the decision diagram on the flashing occurrence was obtained from the test and the analytical results, taking into consideration three factors: the depressurizing ratio in the tank; the cold water injection flow rate due to remaining subcooling; and the delay time of thermal mixing. The simplified analytical equation was used to decrease the cold water injection flow rate by the optimized pipe length between the mixing tee junction and the drain pump. The cold water injection flow rate was minimized when the pipe length was about 15 to 20 times the pipe inner diameter. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(5): 411,429, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10096 [source] Computation of heat transfer enhancement in a plate-fin heat exchanger with triangular inserts and delta wing vortex generatorINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 9 2010Gulshan Sachdeva Abstract Longitudinal vortices disrupt the growth of the thermal boundary layer, thereby the vortex generators producing the longitudinal vortices are well known for the enhancement of heat transfer in compact heat exchangers. The present investigation determines the heat transfer characteristics with secondary flow analysis in plate fin triangular ducts with delta wing vortex generators. This geometrical configuration is investigated for various angles of attack of the wing i.e. 15°, 20°, 26° and 37° and Reynolds numbers 100 and 200. The constant wall temperature boundary condition is used. The solution of the complete Navier Stokes equation and the energy equation is carried out using the staggered grid arrangement. The performance of the combination of triangular secondary fins and delta wing with stamping on slant surfaces has also been studied. Copyright © 2009 John Wiley & Sons, Ltd. [source] Fringe element reconstruction for front tracking for three-dimensional incompressible flow analysisINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 6 2005Du-Soon Choi Abstract Fringe element reconstruction technique for tracking the free surface in three-dimensional incompressible flow analysis was developed. The flow field was calculated by the mixed formulation based on a four-node tetrahedral element with a bubble function at the centroid (P1+/P1). Since an Eulerian approach was employed in this study, the flow front interface was advected by the flow through a fixed mesh. For accurate modelling of interfacial movement, a fringe element reconstruction method developed can provide not only an accurate treatment of material discontinuity but also surface tension across the interface. The effect of surface tension was modelled by imposing tensile stress directly on the constructed surface elements at the flow front interface. To verify the numerical approach developed, the developed algorithm was applied to two examples whose solutions are available in references. Good agreement was obtained between the simulation results and these solutions. Copyright © 2005 John Wiley & Sons, Ltd. [source] The harmonic adjoint approach to unsteady turbomachinery designINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 3-4 2002M. C. Duta Abstract In recent years, there has been rapid progress in aerodynamic optimization methods which use adjoint flow analysis to efficiently calculate the sensitivity of steady-state objective functions to changes in the underlying design variables. This paper shows that the same adjoint approach can be used in turbomachinery applications in which the primary concern is blade vibration due to harmonic flow unsteadiness. The paper introduces the key engineering concepts and discusses the derivation of the adjoint analysis at the algebraic level. The emphasis is on the algorithmic aspects of the analysis, on the iterative solution method and on the role played by the strong solid wall boundary condition, in particular. The novel ideas are exploited to reveal the potential of the approach in the minimization of the unsteady vibration of turbomachinery blades due to incident wakes. Copyright © 2002 John Wiley & Sons, Ltd. [source] Extended evidence on the use of technical analysis in foreign exchangeINTERNATIONAL JOURNAL OF FINANCE & ECONOMICS, Issue 4 2006Thomas Gehrig Abstract This work extends earlier survey studies on the use of technical analysis by considering flow analysis as a third form of information production. Moreover, the survey covers FX dealers and also the rising fund managers. Technical analysis has gained importance over time and is now the most equally spread kind of analysis. It has by far the greatest importance in FX dealing and is second in fund management. Charts are used for shorter-term forecasting horizons while flows dominate at the shortest-term and fundamentals at longer horizons. Preferred users of each kind of analysis exhibit different views about market frictions. Copyright © 2006 John Wiley & Sons, Ltd. [source] Materials Metabolism Analysis of China's Highway Traffic System (HTS) for Promoting Circular EconomyJOURNAL OF INDUSTRIAL ECOLOGY, Issue 4 2010Zongguo Wen Summary With the rapid growth of highway mileage and vehicles, the Chinese highway traffic system (HTS) has become one of the great resource consumers. This article attempts to evaluate the material metabolism of China's HTS during 2001,2005 using the approach of material flow analysis (MFA) and to explore possible measures to promote circular economy throughout HTS. We measured a set of indicators to illustrate the whole material metabolism of China's HTS. The results indicated that the direct material input (DMI) of China's HTS increased from 1181.26 million tonnes (Mt) in 2001 to 1,874.57 Mt in 2005, and about 80% of DMI was accumulated in the system as infrastructure and vehicles. The domestic processed output (DPO) increased by 59.0% from 2001 to 2005. Carbon dioxide and solid waste accounted for 80.5% and 10.4% of DPO, respectively. The increase of resource consumption and pollutant emissions kept pace with the growth of transportation turnover. All these suggest that China's HTS still followed an extensive linear developing pattern with large resource consumption and heavy pollution emissions during the study period, which brought great challenges to the resources and the environment. Therefore, it's high time for China to implement a circular economy throughout the HTS by instituting resource and energy savings, by reducing emissions in the field of infrastructure construction and maintenance, by reducing vehicles' energy and materials consumption, and by recycling waste materials. [source] Analyzing Polyvinyl Chloride in Japan With the Waste Input,Output Material Flow Analysis ModelJOURNAL OF INDUSTRIAL ECOLOGY, Issue 5 2009Shinichiro Nakamura Summary Effective life cycle management of polyvinyl chloride (PVC) calls for the separation of end-of-life PVC products at the time of collection not only from other wastes but among different PVC types as well. Information about the flow of PVC products in the economy is important for this purpose. Within the framework of the Japanese input,output (IO) table for the year 2000, with around 400 industry sectors, the flow of PVC is captured in terms of six PVC-embodying products and in terms of three PVC types, (1) flexible PVC (soft PVC), (2) rigid PVC (hard PVC), and (3) others. The degree of resolution; the consideration of different PVC types, which are seldom performed in the material flow analysis (MFA) literature; and the use of waste input,output material flow analysis (WIO-MFA) represent distinguishing features of our study. The use of WIO-MFA methodology enables one to convert a monetary input,output table into a physical interindustry flow table involving an arbitrary number of materials under full consideration of the mass balance. The results indicate that 40% of the PVC produced in Japan is exported (as resins and as products such as passenger motor cars), and the rest is accumulated mostly as capital stock. The largest share of accumulation goes to public construction in the form of plates, pipes, and bars, which are mostly hard-PVC products. [source] Smart Labels for Waste and Resource ManagementJOURNAL OF INDUSTRIAL ECOLOGY, Issue 2 2008An Integrated Assessment Summary This article explores the potential of RFID (radio frequency identification device) for improving the current waste and resource management system in Switzerland. It presents the following three possible options for utilizing RFID tags to support waste management processes: "at source automation" (using a "smart" trash can), "end of pipe I" (combination of the current system with an additional separation of recyclables before incineration), and "end of pipe II" (replacement of the current recycling infrastructure by sorting at the incineration plant). These options tackle the waste and resource management chain during different processes (i.e., waste generation, waste separation, and treatment). Based on an MFA (material flow analysis), we performed a multicriteria assessment of these options with experts from the waste management sector. The assessment of ten experts in the waste management field regarding the proposed options for batteries and electrical appliances showed that, from an ecological perspective, the implementation of RFID in waste management would be desirable and would lead to an improvement in the current recycling rate in Switzerland for the goods studied. From an economic perspective, new investments would be required in the range of 1 to 5 times the maintenance costs of the current separate collection system. From a social perspective, the utilization of RFID tags in the waste management process was ambiguous. In particular, the end of pipe II option would, on the one hand, significantly improve convenience for consumers. On the other hand, experts see privacy and, what is more, social responsibility as being under threat. The experts considered the ecological and social aspects to be more relevant than the economic ones, preferring the end of pipe I option over the other options and the status quo. [source] Substance Flow Analysis of Mercury Intentionally Used in Products in the United StatesJOURNAL OF INDUSTRIAL ECOLOGY, Issue 3 2007Alexis Cain Mercury-containing products release mercury (Hg) throughout their lifecycles, frequently in ways that are difficult to measure directly. Therefore, there are considerable uncertainties about the magnitude of mercury releases associated with products, about which products and which release pathways contribute the most to mercury releases, and about the likely impact on mercury releases of various possible interventions in the mercury content of products or in the management of mercury-containing wastes. This article presents an effort to use substance flow analysis to develop improved estimates of the environmental releases caused by mercury-containing products and to provide policy-makers with a better understanding of opportunities for reducing releases of mercury caused by products. [source] Assessment of the Automobile Assembly Paint Process for Energy, Environmental, and Economic ImprovementJOURNAL OF INDUSTRIAL ECOLOGY, Issue 1-2 2004Geoffrey J. Roelant A coat of paint adds considerable value to an automobile. In addition to consuming up to 60% of the energy needed by automobile assembly plants, however, the painting process also creates both economic and environmental impacts. This study investigated the degree of cost and environmental impact improvement that can be expected when modifications are considered for existing paint processes through heat integration. In order to accomplish this goal, a mathematical model was created to describe the energy use, costs, and environmental impacts from energy consumption in an automobile assembly painting facility. The model agrees with measured energy consumption data for process heating and electricity demand to within about 15% for one Michigan truck facility from which model input parameters were obtained. Thermal pinch analysis determined an energy conservation target of 58% of paint process energy demand. A heat exchanger network optimization study was conducted in order to determine how closely the network design could achieve this target. The resulting heat exchanger network design was profitable based on a discounted cash flow analysis and may achieve reductions in total corporate energy consumption of up to 16% if implemented corporatewide at a major automobile manufacturer. [source] Materials and Energy Flow Analysis of Paper Consumption in the United Kingdom, 1987-2010JOURNAL OF INDUSTRIAL ECOLOGY, Issue 3 2001Erik Sundin Summary This article presents the results of a life-cycle materials and energy flow analysis for the pulp and paper cycle in the United Kingdom. Material flows are reconstructed for the period be-tween 1987 and 1996 for all major processes associated with the paper cycle, and system energy requirements are calculated over this period using the best available data. Attention is drawn to the import dependence of U.K. paper demand, and the significant energy requirements associated with upstream forestry processes. The historical trend analysis is then used to model possible future developments in materials and energy consumption until 2010 under a variety of assumptions about process technology improvements, wastepaper utilization rates, and changing demand trends. The results indicate that policy options to increase recycling yield some energy benefits, but these are small by comparison with the benefits to be gained by reducing consumption of paper and improving process technology. The structure of the electricity supply industry in the United Kingdom means that global energy benefits could also be achieved by increasing the contribution from imported pulp. [source] MR-based visualization and quantification of three-dimensional flow characteristics in the portal venous systemJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2010Zoran Stankovic MD Abstract Purpose: To evaluate the feasibility of time-resolved flow-sensitive MRI for the three-dimensional (3D) visualization and quantification of normal and pathological portal venous (PV) hemodynamics. Materials and Methods: Portal venous hemodynamics were evaluated in 18 healthy volunteers and 5 patients with liver cirrhosis. ECG- and adaptive respiratory navigator gated flow-sensitive 4D MRI (time-resolved 3D MRI with three-directional velocity encoding) was performed on a 3 Tesla MR system (TRIO, Siemens, Germany). Qualitative flow analysis was achieved using 3D streamlines and time-resolved particle traces originating from seven emitter planes precisely placed at anatomical landmarks in the PV system. Quantitative analysis included retrospective extraction of regional peak and mean velocities and vessel area. Results were compared with standard 2D flow-sensitive MRI and to the reference standard Doppler ultrasound. Results: Qualitative flow analysis was successfully used in the entire PV system. Venous hemodynamics in all major branches in 17 of 18 volunteers and 3 of 5 patients were reliably depicted with good interobserver agreement (kappa = 0.62). Quantitative analysis revealed no significant differences and moderate agreement for peak velocities between 3D MR and 2D MRI (r = 0.46) and Doppler ultrasound (US) (r = 0.35) and for mean velocities between 3D and 2D MRI (r = 0.41). The PV area was significantly (P < 0.01) higher in 3D and 2D MRI compared with US. Conclusion: We successfully applied 3D MR velocity mapping in the PV system, providing a detailed qualitative and quantitative analysis of normal and pathological hemodynamics. J. Magn. Reson. Imaging 2010;32:466,475. © 2010 Wiley-Liss, Inc. [source] FLOW ANALYSIS OF LANDSLIDE DAMMED LAKE WATERSHEDS: A CASE STUDY1JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2006Kwan Tun Lee Abstract: The Chi-Chi earthquake, which occurred on September 21, 1999, and had a magnitude of 7.3 on the Richter scale, resulted in an extensive landslide that blocked the Ching-Shui Creek in Taiwan, forming a large lake with a storage volume of 40 million m3. This paper describes an analytical procedure used to perform flow analysis of the Tsao-Ling watershed, which includes the new landslide dammed lake. In this study, a digital elevation model was applied to obtain the watershed geomorphic factors and stage-area storage function of the landslide dammed lake. Satellite images were used to identify the landslide area and the land cover change that occurred as a result of the earthquake. Two topography-based runoff models were applied for long term and short term streamflow analyses of the watershed because the watershed upstream of the landslide dam was ungauged. The simulated daily flow and storm runoff were verified using limited available measured data in the watershed, and good agreement was obtained. The proposed analytical procedure for flow analysis is considered promising for application to other landslide dammed lake watersheds. [source] Rheological properties of three different vitamin D ointments and their clinical perception by patients with mild to moderate psoriasisJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 2005JP Marty ABSTRACT Background, Ointments, classically used for the treatment of dermatological diseases, are monophasic viscous semisolid formulations. According to the proportion of their compounds, they have physicochemical and organoleptic properties and when applied on skin show a specific behaviour allowing to be spread more or less easily. Objective, To measure in vitro rheological characteristics of three vitamin D derivative ointments prescribed for the treatment of psoriasis, and to compare their viscosity and clinical acceptability when applied on the diseased skin. Methods, Rheological characteristics of tacalcitol 4 µg/g, calcipotriol 50 µg/g and calcitriol 3 µg/g ointments were assessed by measuring the oscillatory viscoelastic parameters and the permanent flow analysis. Clinical acceptability was studied in 20 psoriatic male or female subjects, aged 18 years or older. A survey evaluated the acceptability of calcitriol vs. tacalcitol and calcipotriol. Questions included information about fluidity, spreading capacity and stickiness after application. Results, We demonstrated that viscoelastic parameters were four times higher for ointment tacalcitol than for calcipotriol and calcitriol, corresponding to a higher consistency of ointment tacalcitol compared to calcipotriol and calcitriol showing both similar results; better fluidity was demonstrated by calcitriol than by tacalcitol and calcipotriol. Comparable results were obtained for the quality to be spread. The sensation of stickiness, significantly different between tacalcitol and calcitriol, was not different between calcipotriol and calcitriol. Conclusion, The above results confirm the relationship between rheological in vitro and sensorial in vivo results: variations between different formulations may have an important influence on non-adherence and treatment failure. [source] Simulation of Agglomerate Dispersion in Cubic Cavity FlowMACROMOLECULAR THEORY AND SIMULATIONS, Issue 3 2009Mahdi Salami Hosseini Abstract Agglomerate dispersion and deformation is simulated and studied in a cavity flow, as a typical three-dimensional flow field, using Stokesian dynamics and macroscopic flow analysis. The break-up and deformation behaviors of two different agglomerate structures , loose, with fractal dimension FD,=,1.8, and dense, with FD,=,2.6 , are examined in different flow paths. The interparticle forces are calculated using van der Waals and Born forces. Results show that agglomerates with a dense structure break-up through detachment, while ones with a loose structure deform and break into fragments through rupture. It was also found that the rearrangement of particles in the agglomerate can postpone break-up in flow fields where rotation occurs, since it can dissipate stress through rearrangements. [source] | ||||||||||||||||||||||