Soils are a source of oxides of nitrogen (NO(sub x) = nitric oxide and nitrogen dioxide), precursors for the production of ozone (O(sub 3)), an air pollutant in the troposphere. Production of nitric oxide (NO) occurs through soil microbial processes using ammonium from nitrogen fertilizer and manure inputs or soil mineral nitrogen (N). Emissions of NO(sub x) were measured in almond, alfalfa, tomato, wheat, and silage corn cropping systems during summer months to obtain estimates of NO(sub x) emissions that could potentially be used in regional models predicting O(sub 3) in the San Joaquin Valley. The lowest average NO(sub x) fluxes (40 g NO(sub x)-N ha(sup -1) h(sup -1)) were measured. These high NOx flux events are difficult to predict.

关键词：大气；土壤系统；种植策略

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The paper proposes a method to reduce operational force in a bilateral teleoperation system that realizes simultaneity property under communication delay. A bilateral control that realizes simultaneity property is previously proposed, which is achieved by buffering the force information. It focused on the fact that force information from the master motor is the pure information that actuates the motor, therefore, timing of the force information input is corrected. However, the control system requires large force when operator tries to operate the system. The paper clears the reason and the problem is solved by utilizing the delayed position information of the own system. The proposed control system is designed to mix present and buffered position information to reduce the operational force. The delayed information can easily affect the stability problem, therefore, phase compensator is used. The validity of the proposed method is confirmed by experiments.

关键词：加速度控制；双向控制系统；通信延迟

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The Florida Department of Transportation (FDOT) has released a report that discusses possible human exposure and environmental emissions associated with making and using concrete manufactured with baghouse filter dust.

关键词：大气；粉尘；混凝土防护

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This measure guideline offers additional recommendations to heating, ventilation, and air conditioning (HVAC) system designers for optimizing flexible duct, constant-volume HVAC systems using junction boxes within Air Conditioning Contractors of America (ACCA) Manual D guidance (Rutkowski, H. Manual D -- Residential Duct Systems, 3rd edition, Version 1.00. Arlington, VA: Air Conditioning Contractors of America, 2009.). IBACOS used computational fluid dynamics software to explore and develop guidance to better control the airflow effects of factors that may impact pressure losses within junction boxes among various design configurations (Beach, R., Prahl, D., and Lange, R. CFD Analysis of Flexible Duct Junction Box Design. Golden, CO: National Renewable Energy Laboratory, submitted for publication 2013). These recommendations can help to ensure that a system aligns more closely with the design and the occupants' comfort expectations. Specifically, the recommendations described herein show how to configure a rectangular box with four outlets, a triangular box with three outlets, metal wyes with two outlets, and multiple configurations for more than four outlets. Designers of HVAC systems, contractors who are fabricating junction boxes on site, and anyone using the ACCA Manual D process for sizing duct runs will find this measure guideline invaluable for more accurately minimizing pressure losses when using junction boxes with flexible ducts.

关键词：空气流量；计算流体动力学；配置

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The synthesis and physical properties of new silicon-containing polyfunctional cyanate ester monomers tris(4-cyanatophenyl)methylsilane and tetrakis(4-cyanatophenyl)silane, as well as polycyanurate networks formed from these monomers are reported. The higher cross-linking functionality compared to di(cyanate ester) monomers enables much higher ultimate glass transition temperatures to be obtained as a result of thermal cyclotrimerization. The ability to reach complete conversion is greatly enhanced by cocure of the new monomers with di(cyanate ester) monomers such as 1,1-bis(4-cyanatophenyl)ethane (LECy). The presence of silicon in these polycyanurate networks imparts improved thermochemical stability in air compared to carbon-containing analogs in cases where the thermochemical performance in air is significantly worse than under nitrogen. The water uptake in the silicon-containing networks examined is 4 - 6 wt% after 96 hours of immersion at 85 degrees C, considerably higher than both carbon-containing and/or di(cyanate ester) analogs.

关键词：固化动力学；固化；氰酸酯；氰酸酯

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In this chapter, the problem of approximate linearization of affine nonlinear control systems by a static state feedback is considered. First of all, we propose an analytical method, based on the development into generalized Taylor series expansions and the Kronecker product tools, in order to simplify the complex implementation of the input-state feedback linearization formalism. Next, to improve the synthesized polynomial feedback control, the genetic algorithm, as an optimization method, is used. Finally, the new approach presented in this work is applied to investigate the control problem of a chemical reactor. Moreover, we prove that the controlled process is locally asymptotically stable in a wide region around the operating point, in the Lyapunov sense.

关键词：反馈线性化；多项式非线性控制；优化程序

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H_2 and H_∞ optimal control are two important breakthroughs in modern robust control. In recent years, the H_2 and H_∞ controller design techniques have gained a lot of research attention. Both have strong theoretical basis and are efficient algorithms for synthesizing optimal controllers. The performance of H_2 robust controller is useful to handle stochastic aspects such as measurement noise and capture the control cost. In the robust H_2 approach, the controller is designed to minimize an upper bound on the worst case H_2 norm for a range of admissible plant perturbations. When a model under analysis is applied with H_2 robust controller, the closed loop system will have a good dynamic system performance, but it has poor robustness for the external disturbances of the uncertain system model. The performance of H_∞ is convenient to enforce robustness to model uncertainty, but it is based on compromising system performance. Their combination, the mixed H_2/H_∞ allows intuitive quadratic performance specifications of the H_2 synthesis with robust stability requirements specifications expressed by the H_∞ synthesis. In time domain aspects, satisfactory time response and closed loop damping can often be achieved by enforcing the closed loop poles into a predetermined region of the left half plane. Combining these requirements to form so-called mixed H_2/H_∞ design with regional pole placement constraints allows for more flexible and accurate specification of closed-loop behavior. This chapter introduces the work of design of improved LMI-based robust output feedback controller and related simulations.

关键词：线性矩阵不等式（LMI）；电力系统稳定器（PSS）；鲁棒控制

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Waste-to-energy (WTE) technology burns municipal solid waste (MSW) in an environmentally safe combustion system to generate electricity, provide district heat, and reduce the need for landfill disposal. While this technology has gained acceptance in Europe, it has yet to be commonly recognized as an option in the United States. Section 1 of this report provides an overview of WTE as a renewable energy technology and describes a high-level model developed to assess the feasibility of WTE at a site. Section 2 reviews results from previous life cycle assessment (LCA) studies of WTE, and then uses an LCA inventory tool to perform a screening-level analysis of cost, net energy production, greenhouse gas (GHG) emissions, and conventional air pollution impacts of WTE for residual MSW in Boulder, Colorado. Section 3 of this report describes the federal regulations that govern the permitting, monitoring, and operating practices of MSW combustors and provides emissions limits for WTE projects.

关键词：大气；空气改善；空气治理

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This project examined the Montana DOTs current methods for determining projects for the Montana Air and Congestion Initiative (MACI) program, and made recommendations to improve and implement this program. A major project objective was to keep the program oriented towards high-value investments for Montana communities. Key project tasks included: (1) Determine the best use of Congestion Mitigation and Air Quality (CMAQ) funds for each of Montanas transportation-related pollutants (2) Determine project recommendations that use highest cost to air quality benefit for long-term attainment (3) Determine needed funding and program policy changes (4) Identify areas prone to future transportation-related issues (5) Determine need for education in Montana communities on best practices to prevent nonattainment of transportation related pollutants One of the primary products of this research is a set of methods descriptions and MS Excel-based tools that are designed for MDT staff and other Montana agencies to use to estimate the air pollution emission reduct and the cost effectiveness of the new measures and projects that are being considered in the state.

关键词：大气；空气污染；空气质量

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Force estimation is one of the most important techniques in the robot control application. In this research, acceleration sensor based load-side disturbance observer (ALDOB) is proposed and developed by integrating an acceleration sensor on the load side and the optical encoder on the motor side in order to estimate external force. The enhancement of the force estimation was found to increase. Good estimation of force and robust force control could be obtained using ALDOB observer. The simulation results are provided to illustrate the performance of the proposed algorithms. A flexible robot model was established to simulate the robot dynamic in force control, and the results agree with the analysis.

关键词：力控制；扰动观测；加速度传感器

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