Spintronics is the advanced branch of nanoelectronics making use of specially engineered materials that can impart spin functionality in the electrons, in addition to its well-known property of charge. Spin field effect transistor (spin-FET) is a spin-device consisting of ferromagnetic source and drain electrodes to impart spin-functionality into the device with the spin field effect transistor action realized with an electric field applied through the gate voltage. The whole concept relies on controlling the spin precession from source to the drain through a spin-conducting channel by applying a voltage on the gate region. An interesting class of materials is the half-metallic ferromagnetic compounds having majority spin density of states at the Fermi level (E_F) showing metallic behaviour, while minority spin density of states at a certain gap below the E_F. CrO_2 is such a half-metallic oxide with theoretical predicted 100% degree of spin-polarization and high Curie temperature (T_C) of ～395 K making it appropriate for spin-device applications. Hence, nanotechnology is the technology of the future, giving rise to the design of new kinds of materials (electronic & magnetic) and devices based on them, all set to revolutionize the world.

关键词：自旋电子学；纳米技术；自旋电子学；自旋金属氧化物

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Present day consumers have wide variety of demands and needs leads to increased complexity in automobiles. The price war and high quality, imposes the automobile manufacturers to have flexible design with zero defects in a highly competitive market. Unlike other industry, the quality of automobile depends on parts (manufactured and supplied by third party supplier) used and on the assembling the vehicle. To achieve the high quality that is demanded by the customers, manufacturers and their suppliers must rely on Machine Vision to prevent defects at multiple stages of production. Machine Vision can be used to inspect the quality of automobile parts, pick and place using robots, assembly line (inspection before, after and placement verification), to find missing parts, completeness, welding and painting guiding on finished automotive bodies. In addition to this, Machine Vision is also used for parts traceability decoded by reading OCR, data matrix and barcode. Different automobiles can have different quality of parts depending on price range. Machine Vision can also be used to classify automotive parts based on the required quality using measurements. This publication explains the basics of machine vision and explore the solutions that can be used in automobile industry at different stages of production.

关键词：图片来源；X射线图像；数学形态学；图像处理

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Multiphase flows commonly occur in the production and transportation of oil, natural gas and water. In this type of flow, the phases can flow in different spatial configurations disposed inside the pipe, so called multiphase flow patterns. The identification of flow patterns and the determination of the pressure drop along the pipe lines for different volumetric flows are important parameters for management and control of production. In this sense, this work proposes to numerically investigate the non-isothermal multiphase flow of a stream of ultraviscous heavy oils containing water and natural gas in submerged risers (catenary) via numerical simulation (ANSYS CFX 11.0). Results of the pressure, volumetric fractions and temperature distributions are presented and analyzed. Numerical results show that the heat transfer was more pronounced when using the largest volume fraction of gas phases.

关键词：重油；管道；多相流；传播热量；数值模拟

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A suboptimal approach to distributed Nonlinear Model Predictive Control (NMPC) for systems consisting of nonlinear subsystems with nonlinearly coupled dynamics subject to both state and input constraints is proposed. The approach applies a dynamic dual decomposition method to reformulate the original centralized NMPC problem into a distributed quasi-NMPC problem by linearization of the nonlinear system dynamics and taking into account the couplings between the subsystems. The developed approach is based entirely on distributed on-line optimization (by gradient iterations) and can be applied to large-scale nonlinear systems. The theoretical results related to the application of the distributed MPC approach to both linear and nonlinear systems are outlined and some simulation results are provided.

关键词：分散非线性模型；预测控制；在线优化

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The present work aims to study convection and heat transfer and mass in a porous cubic cavity. The configuration considered is a cavity cube with vertical walls left and right are subjected to temperatures required while others are impermeable and adiabatic. We realized that the results depend on several characteristic parameters, and general correlations are established for the calculation of heat and mass transfer, according to various studied parameters. The study focuses on the influence of the control parameters on the structure of the flow, heat and mass transfer.

关键词：立体感；自然对流；温盐；多孔介质

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We address the problem of efficient implementations of distributed Model Predictive Control (MPC) systems for large-scale plants. We explore two possibilities of using suboptimal solvers for the quadratic program associated with the local MPC problems. The first is based on an active set method with early termination. The second is based on Partial Enumeration (PE), an approach that allows one to compute the (sub)optimal solution by using a solution table which stores the information of only a few most recently optimal active sets. The use of quick suboptimal solvers, especially PE, is shown to be beneficial because more cooperative iterations can be performed in the allowed given decision time. By using the available computation time for cooperative iterations rather than local iterations, we can improve the overall optimality of the strategy. We also discuss how input constraints that involve different units (for example, on the summation of common utility consumption) can be handled appropriately. Our main ideas are illustrated with a simulated example comprising three units and a coupled input constraint.

关键词：分布式模型；次优解算器；MPC

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Illinois Carbon Monoxide Screen for Intersection Modeling (COSIM) Version 3.0 is a Windows-based computer program currently used by the Illinois Department of Transportation (IDOT) to estimate worst-case carbon monoxide (CO) concentrations near signalized intersections in Illinois. Modeled results from COSIM are based on the U.S. Environmental Protection Agency's (EPA's) mobile source emission model, MOBILE6.2, and roadway dispersion model, CAL3QHC v 2.0. Emission factor (EF) tables derived from MOBILE6.2 are incorporated directly into COSIM's program coding. Recent regulatory changes in mobile source emissions modeling have prompted IDOT to update the EFs used in COSIM with EFs estimated using EPA's Motor Vehicle Emission Simulator (MOVES) mobile source emission model. This report documents the changes made to COSIM, Version 3.0, that allow IDOT to continue to use COSIM (Version 4.0) to estimate worst-case CO concentrations for proposed roadway projects with signalized intersections in 2013 and beyond.

关键词：大气；空气污染；空气质量检测

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The 2010 EPA emissions regulation for NOx is 0.2 g/bhr-hr, and the EPA has started to certify vehicles that can actually meet this regulation. Most manufacturers had initially opted instead to meet a Family Emission Limit (FEL) around 1.2-1.5 g/bhp-hr NOx with most of their vehicle emissions lying between the two standards. Currently the EPA has certified engines with both the Exhaust Gas Recirculation (EGR) and Selective Catalytic Reduction (SCR) technologies to meet the strict 0.2 g/bhr-hr NOx standard. While there is only one EGR system that has been certified by the EPA as meeting 2010 emissions regulations (Navistar, Inc.), there are several SCR systems that can meet this requirement (Cummins, Detroit Diesel, Volvo etc.). Moreover the SCR system in addition to meeting emissions regulations can result in a 3 to 5.5% increase in fuel efficiency. The SCR system typically uses a zeolite NOx adsorption catalyst that can selectively adsorb NOx molecules during lean burn operation and convert it to N2 and H2O with the injection of an urea water solution called Diesel Exhaust Fluid (DEF). It is the technology of choice for emissions control in Europe and several manufacturers have adopted this for the United States. SCR systems require tuning to work properly and systems can be tuned with either preexisting engine performance curves or with NOx/NH3 sensors. The use of NOx/NH3 sensors can provide closed loop control of the SCR system that can optimize the system for improved NOx reduction efficiencies and low NH3 slip. According to a recent review Reliable and accurate NOx sensors will be the key to the management of adsorption catalysts. The optimized use of SCR systems can increase the value for the customer with fuel and DEF savings (including reduced frequency and costs of the dealer servicing of the emissions system consumables) over the life of the vehicle helping defray the added cost of the system.

关键词：大气；废气排放；废气转化处理；大气污染

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DOD maintains the evidence is inconclusive regarding whether exposure to burn pit emissions creates a long-term health risk for deployed personnel. Contrary to this position, several military professionals maintain the evidence is clear. An Air Force physician at Balad Air Base concurred with a 2006 memorandum and stated: In my professional opinion, the known carcinogens and respiratory sensitizers released into the atmosphere by the burn pit present both an acute and a chronic health hazard to our troops and the local population. A 2011 memorandum from an Army Officer cited evidence that air quality on Bagram Air Field was 'unhealthy' and concluded that the primary contributor was the burn pit. He also listed potential long-term health risks associated with long-term exposure to air conditions such as those found on Bagram. The 2011 memorandum led to a Congressional inquiry and passage of Public Law 112-260 directing the VA to establish an 'Open Air Burn Pit Registry.' This paper will examine studies on exposure to open-air burn pits, look at the recent legislation and potential ramifications for the VA system, and will conclude with a review of technology that might be implemented to abolish open-air burn pits.

关键词：大气；空气污染；空气健康

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No abstract available.

关键词：大气；气体成分；气候变化；空气分析

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