This paper proposes two types of force control system based on measurements of an acceleration sensor attached on the tip-position of a 3-link planar redundant manipulator. To estimate the acceleration with high accuracy, Kalman filter(KF) based on dynamic model of the manipulator and extended Kalman filter(EKF) based on kinematic model of that are introduced to each system. Furthermore, Disturbance Force Observer(DFOB) and Reaction Force Observer(RFOB) are also implemented in the force control system, and estimated acceleration information by KF/EKF is directly utilized in those observers. Experiments are conducted to examine the characteristics of estimation performance and compare the force control performance based on each of KF and EKF.

关键词：力控制；冗余机械臂；加速度传感器

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Lawmakers could increase federal revenues and encourage reductions in emissions of carbon dioxide (CO2) by establishing a carbon tax, which would either tax those emissions directly or tax fuels that release CO2 when they are burned (fossil fuels, such as coal, oil, and natural gas). Emissions of CO2 and other greenhouse gases accumulate in the atmosphere and contribute to climate changea long-term and potentially very costly global problem. The effects of a carbon tax on the U.S. economy would depend on how the revenues from the tax were used. Options include using the revenues to reduce budget deficits, to decrease existing marginal tax rates (the rates on an additional dollar of income), or to offset the costs that a carbon tax would impose on certain groups of people. This study examines how a carbon tax, combined with those alternative uses of the revenues, might affect the economy and the environment.

关键词：大气；碳税；经济

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The growth of high-quality organic semiconductors on supporting substrates with minimal disorder is the key requirement for realizing high-performance organic electronics. However, the absence of an epitaxial relation and the presence of disorder make it particularly challenging to grow high-quality organic crystals having few defects and grain boundaries on conventional insulating substrates. Here, we report epitaxial growth of highly ordered, crystalline organic films on van der Waals (vdW) substrates and demonstrate high carrier mobility comparable to those of single-crystal counterparts. High quality rubrene films with large single-crystalline domains were grown on hexagonal boron nitride (h-BN) layers with an in-plane crystallographic registry. Furthermore, using graphene as the vdW electrical contacts, high field-effect mobility (11.5 sq cm V(exp 1) s(exp 1)) was achieved, attributable to an atomically sharp interface with low charge trap density between rubrene and h-BN. The ability to grow high-quality organic/inorganic epitaxial vdW heterostructures, combined with recent progress on large-area growth of layered materials, provides new opportunities for the scalable fabrication of high-performance organic electronic devices. Controlling the interface between organic films and inorganic substrates is of crucial importance for organic electronic applications, because this interface governs the initial nucleation during the growth of molecular films as well as the field-induced charge-carrier transport. In particular, charge transport is affected greatly by interfacial disorder, such as surface roughness and charge traps, as well as structural disorder of the molecular materials at the interface.

关键词：氮化硼；载流子迁移；电荷密度

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It is hoped that the humanoid robot will be able to move flexibly and have excellent object operation capability like human beings. Based on people operation object strategy, this chapter proposes a humanoid robot object operation strategy that integrates the visual feedforward control strategy and the visual feedback control strategy. Using the visual feedforward control strategy, the humanoid robot can walk approaching the target object and make its arm close to the target object; using the visual feedback control strategy, the humanoid robot achieves the robot hand fine alignment with the target object. Based on the visual feedforward control strategy the time of the humanoid robot hand approaching the target object has been reduced; based on the visual feedback control strategy the accuracy of the operation has been improved. Based on the control strategy of this chapter proposed, the humanoid robot will be able to walk and operate objects independently.

关键词：仿人机器人；对象操作；控制策略

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The overarching purpose of this report is to present analysis of the 2008 NEI and comparison to previous years of inventory data, with a primary focus on the last full NEI - the 2005 NEI. We describe the national and regional patterns of CAP/HAP emission distributions in the 2008 NEI and which sources contribute to these releases. We do not assess nor predict the absolute risks to human health and ecosystems that may be associated with the presence of any of these specific air pollutants, but rather focus on the intensity of emission releases that may pose elevated risks. Pollutants of greatest interest include not only those that contribute to ozone and particle pollution, but also HAPs that are predicted by the 2005 NATA to be the most harmful to human health. To facilitate a more concise document, we have included just 27 pollutants in the report, which are listed in Table 1. Eight of these 27 pollutants are either CAPs or precursors to CAPs, and the remaining 19 are HAPs that were selected based on criteria that will be discussed later in this report.

关键词：大气；碳排放；空气污染

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A high-load endurance test was performed on the tail drivetrain of an H-60 Blackhawk helicopter to determine the resistance to gear tooth fracture under power levels exceeding the maximum continuous rating. During posttest inspection, it was found that a tooth had broken off of the tail takeoff spiral bevel gear. In addition, a moderate spall was found on the outer race of the intermediate gearbox input gear shaft support bearing. There were no obvious indications of the gear tooth failure during the duration of the test, making the determination of the time of tooth fracture critical to understanding the resistance of the H-60 tail drivetrain to overloads. This report analyzes vibration data sampled periodically throughout the test to determine the initiation time of these two specific mechanical failures. Both faults occurred naturally in a system environment, making the dataset of particular interest. Several existing gear and bearing vibration analysis techniques were utilized. These methods clearly identified the time of initiation of both the spiral bevel gear tooth fracture and the bearing spall. The capability of the different analysis methods relative to predicting gear tooth crack and bearing spall initiation are compared.

关键词：轴承；诊断设备；故障（力学）；故障诊断

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Based on Lyapunov stabilization theory, this paper proposes a proportional plus integral time-delayed controller to stabilize unstable equilibrium points (UPOs) embedded in chaotic attractors. The criterion is successfully applied to the classic Chua's circuit. Theoretical analysis and numerical simulation show the effectiveness of this controller.

关键词：混沌系统；比例加积分时间延迟控制器；泰勒逼近

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Results from 548,507 indoor radon tests from a database compiled by the Pennsylvania Department of Environmental Protection, Bureau of Radiation Protection, Radon Division, are evaluated in this report in an effort to determine areas where concentrations of radon are highest. Indoor radon concentrations were aggregated according to geologic unit and hydrogeologic setting for spatial analysis. Indoor radon concentrations greater than or equal to the U.S. Environmental Protection Agency (USEPA) action level of 4 picocuries per liter (pCi/L) were observed for 39 percent of the test results; the highest concentration was 1,866.4 pCi/L.

关键词：大气；有毒气体；室内氡

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Cumene (CASRN 98-82-8, isopropylbenzene) is an alkylated benzene found in fossil fuels, such as blended gasoline and kerosene, and products of incomplete combustion (IARC2012). It has a gasoline-like odor and can exist as a vapor in ambient air. 

关键词：大气；空气污染；致癌物质

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A wheeled mobile robot (WMR) belongs to the class of non-holonomic systems with highly nonlinear dynamics. Because of their fast maneuvering and energy saving characteristics, these robots are especially popular in following or tracking a pre-defined trajectory. The trajectory of a WMR is controlled with the help of two very different control schemes namely model dependent approach and model free approach. While the model dependent approach relies on a particular model for the controller design, the model free method controls the trajectory with the help of learning methods. A Direct Model Reference Adaptive Controller (D-MRAC) is described for the model based technique, while an Adaptive Neuro-Fuzzy Inference System (ANFIS) is used for the model-free adaptive control design. With the help of simulations, it is shown that data driven intelligent approach is comparable to model dependent approach in terms of tracking performance and therefore can be preferred over complex model dependent adaptive algorithms.

关键词：移动机器人；自适应控制；人工智能

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