Power variation control of a wind generator by using feed forward control

The pitch control of wind generators is usually made by a feed back control concept. However, under the conditions where a wind speed changes very frequently due to geographic reasons of the site and the target system has large rotor inertia, the feed back signal which is applied to the control system to compensate disturbance such as wind speed variations is delayed, and consequently the control strategy to keep the generated power at a constant value does not work well. If the wind speed shows too much variation, this will cause a violent variation of power and result in step out operation of the generator from the power system due to magnetic saturation. This paper proposes a control strategy to reduce the power variations by introducing feed forward control combining with the conventional feed back control.     

Hand-eye system with three-dimensional vision and microgripper for handling flexible wire

A three-dimensional hand-eye system has been specially developed for handling, forming, and inserting flexible wires in electronic assemblies. The system consists of a vision system capable of measuring three-dimensional positions and a gripper capable of microforce control. The hand-eye system performs its tasks based on visual and force sensor data.The vision system uses a camera, a multiplanar laser light projector, and a video-rate image processor to measure the three-dimensional position of a flexible wire on a complex background. The projector consists of multiplanar light beams and a single-planar light beam and is robot-mountable. The single-planar light is used to simplify the matching of the multiplanar light beams and projection images. This is one of the most important features of our method. The measurement time is within 1.2 s for 20 positions on the wire, which is less than one robot cycle. The measurement accuracy is better than 0.2 mm in the plane for a 100×100 mm scene and is better than 1 mm perpendicular to the plane for a depth of 500 mm.The microgripper has 3-axis sensors capable of detecting three types of forces: grasping, pulling, and pushing. The dynamic range of the grasping force is 0.005 to 0.6 N, enabling high-resolution control. Two piezoelectric actuators are used in the microgripper fingers and a 3-mm stroke is achieved by amplifying the actuator's displacement using a two-stage lever.This system has been used for wire handling in magnetic disk slider manufacture, which is a difficult and delicate task. Measurement, grasping, and upper-stage insertion had a 100 percent success rate using autorecovery, making the hand-eye system feasible. This paper discusses design concepts, the range measurement principle, the system itself, and wire-handling applications.     

Identification of phenolic compounds isolated from pigmented rices and their aldose reductase inhibitory activities

Two anthocyanins (cyanidin-3-O-β-glucoside and peonidin-3-O-β-glucoside) and other phenolic (ferulic acid) were, respectively isolated from black and pigmented brown rices (Oryza sativa L. japonica) and their complete structures were determined by spectroscopic analyses (H NMR, C NMR and MALDI MASS). The HPLC profile of anthocyanins extracted from black rice showed cyanidin-3-O-β-glucoside as the first peak (85%) and peonidin 3-O-β-d-glucoside as the second (15%), while that of pigmented brown rice showed ferulic acid as the first peak (85.7%) and tocols as the second (14.3%). Several tocols were isolated and identified from the unsaponifiable fractions of both rices having some difference on their structures and amounts. The aldose reductase inhibitory activity of isolated compounds was in the following decreasing order: cyanidin-3-glucoside > quercetin > ferulic acid > peonidin-3-glucoside > tocopherol.     

Incline compensation control using an air-spring type active isolated apparatus

In order to avoid the deformation of main body supported by air-spring type active isolated apparatus, a pressure feedback was previously introduced for its isolated apparatus. The primal purpose of this feedback was to suppress the deformation of the main body by controlling air-spring force. Furthermore the author recognize that the incline of the main body due to XY stage scanning will be easily compensated by utilizing that the driving mechanism of air-spring with the pressure feedback becomes an astatic system. If the incline of the main body is effectively corrected, the precise scanning of XY stage is expected because the disturbance for the control loop of XY stage is removed.Firstly, this paper briefly shows the principle of the pressure feedback which provides a basis for the incline compensation. Secondly, the feed-forward scheme for its compensation is clarified. Finally, the experimental results of the incline compensation are shown.     

Coherent Phase Diagram for Spinodal Decomposition in the Tetragonal Titanium Dioxide—Tin Oxide System

A microscopic calculation was carried out for spinodal decomposition in the tetragonal TiO₂—SnO₂ system by taking into account the contribution of the elastic free energy. Necessary elastic constants for the solid solutions and the elastic free energy of modulated structure were calculated in terms of interatomic potentials. A coherent phase diagram was obtained unambiguously from the calculated elastic free energy by using the interaction parameter determined by the experimental binodal line. The results were compared with the calculation based on the regular-solution model.     

Performance analysis of the SOFC–MGT hybrid system with gasified biomass fuel

Analysis of electricity generation efficiency of the biomass SOFC–MGT hybrid system has been made for several cases of different composition of fuel relevant to typical air-, oxygen- and steam-blown biomass gasification processes. Reference case for comparison is the one where pure methane is used as fuel. In the analysis, multi-stage model for internal reforming SOFC module developed previously has been used with some modification. It is found that efficiency achieved for all the three cases of different types for biomass fuel is reasonably high and so that the biomass SOFC–MGT hybrid system is promising. However, in all the three cases, efficiency is lower than the counterpart of pure methane case, both in the SOFC module and in the hybrid system. Among the biomass fuel cases, efficiency is found to be highest with steam-blown biomass fuel both for the SOFC module and for the hybrid system. The lowest efficiency is found in the case of air-blown fuel. In addition, effects of higher steam content in the biomass fuel and variety in composition of biomass fuel for each gasifying agent are also studied.     

Technology choice and CDM projects in China: case study of a small steel company in Shandong Province

Corporate motives and strategies of both investing and hosting country affect the outcomes of a clean development mechanism (CDM) project—who introduces what technology to whom—and result in large differences in economic viability and the CO₂ emission reductions. This is particularly true for steel industry in which steel making consists of many detailed and complex processes, a given strategy could produce cumulative effects of the individual technologies used, leading to large energy savings overall. The objective of this study is to demonstrate some analytical methods that can be used to quantitatively evaluate the impacts of technology selection on the profit performance of CDM projects. Specifically, in this study we analyze a CDM project to introduce energy saving technology from Japan to a small steel manufacturer in China's Shandong Province, and conduct a simulation of the quantitative relationships between various technology options and profitability. Based on these results, we examine the environmental and economic significance of technology selection for CDM projects. To take this further, we then reconsider the profitability of a project as typical FDI activity (i.e., without the CDM), and by comparing this outcome with the CDM case, we clarify the significance and potential of the CDM.     

Transition to Quantum Turbulence and the Propagation of Vortex Loops at Finite Temperatures

We performed numerical simulation of the transition to quantum turbulence and the propagation of vortex loops at finite temperatures in order to understand the experiments using vibrating wires in superfluid ⁴He by Yano et al. We injected vortex rings to a finite volume in order to simulate emission of vortices from the wire. When the injected vortices are dilute, they should decay by mutual friction. When they are dense, however, vortex tangle are generated through vortex reconnections and emit large vortex loops. The large vortex loops can travel a long distance before disappearing, which is much different from the dilute case. The numerical results are consistent with the experimental results.     

苏州多层住宅建筑生命周期评价

依据美国开发的BEES软件,选择张家港当地某一栋具体的多层住宅建筑(6层,每层大约750 m2)进行了生命周期评价.把建筑的全生命周期范围确定为建材准备阶段(包括原材科开采、运输、原材料加工等)、建造阶段、运行阶段(运行70年)、拆毁阶段和建筑垃圾处理阶段.依据确定的范围进行了清单分析.根据建筑的结构形式,计算得到各种建材的需求量和建造、运行、拆毁、建筑垃圾处理时的各种输入输出,以统一的功能单位(一栋建筑)合并各种输入输出数据,得到总的数据清单.采用BEES分类表征方法进行影响评价.根据我国的具体情况确定环境影响因子和类别(酸雨、全球变暖、资源枯竭等),将不同的环境影响因子分配到一个或多个环境影响类别中,再根据具体情况确定各指标的权重系数进行加权,得到综合的评价结果.找出了建筑物全生命周期阶段中产生环境影响最大的阶段,即运行阶段.