Three-dimensional simulating of concentrator photovoltaic modules using ray trace and equivalent circuit simulators

A 3-dimensional (3D) simulation for a concentrator photovoltaic (CPV) module using a triple-junction solar cell was developed. By connecting ray-trace simulation for an optics model and 3D equivalent circuit simulation for a triple-junction solar cell, the operating characteristics of a CPV module were calculated. By using the 3D simulation, we considered the influence of tracking error on the CPV module. It was found that maximum output power was not correlated with optical efficiency of the optics system and was strongly dependent on fill factor. We can use this total 3D simulation for the evaluation and optimization of CPV modules.     

Study on performance and flow field of an undershot cross-flow water turbine comprising different number of blades

Recently,small hydroelectric generators have gained attention as a further development in water turbine technology for ultra low head drops in open channels.The authors have evaluated the application of cross-flow water turbines in open channels as an undershot type after removing the casings and guide vanes to substantially simplify these water turbines.However,because undershot cross-flow water turbines are designed on the basis of cross-flow water turbine runners used in typical pipelines,it remains unclear whether the number of blades has an effect on the performance or flow fields.Thus,in this research,experiments and numerical analyses are employed to study the performance and flow fields of undershot cross-flow water turbines with varying number of blades.The findings show that the turbine output and torque are lower,the fluctuation is significantly higher,and the turbine efficiency is higher for runners with 8 blades as opposed to those with 24 blades.     

Detailed Analysis of Temperature Characteristics of an InGaP/InGaAs/Ge Triple-Junction Solar Cell

Temperature characteristics of an InGaP/InGaAs/Ge triple-junction solar cell were analyzed in detail using an equivalent circuit calculation. The current–voltage (I–V) characteristics of single-junction solar cells (InGaP, InGaAs, Ge solar cells) were measured at various temperatures. Fitting of I–V curves between measured and calculated data was carried out, and the diode parameters and temperature exponents of the single-junction solar cells were extracted. The parameters for each single-junction solar cell were used in the equivalent circuit model for the triple-junction solar cell, and calculations of solar cell performance were carried out. Measured and calculated results of the I–V characteristics at various temperatures agreed well.     

爱知县淑德大学8号楼

在有较大高差台地的校园园区内排列鳞次栉比的校舍,建筑物之间诸多大小不等的室外围合空间是整个校园空间的主要特征。将教室、食堂之间的空间为活泼好动的学生营造成最具活力的“舞台”,在这个“舞台”上由室内外一体化的缓坡、大台阶、廊桥等各要素从一层到三层构成连续的断面,不管哪一层的人们都能感受到其他各层活动的情况,是充满“动感”的空间。建筑物宽18m,长92m,形状非常细长,横向由6m和12m两种柱距组成,长向由4m的柱距均分构成连续的架构,这个模数使不同用途和大小的空间(24～336m2)都能获得良好的开间一进深比例,4m跨度的构架单元…     

Wireless Body Area Network Combined with Satellite Communication for Remote Medical and Healthcare Applications

Wireless Body Area Network (WBAN) is expected to play an important role in supporting medical and healthcare services with increased convenience and comfort. One main advantage of WBAN is that it enables automatic biosignal collection in real time which is essential in medical treatment and healthcare vigilance. To harmonize with the strong demands from both medical and healthcare societies, and information and communications technology industries, IEEE 802 Standard Committee set up a task group of TG15.6 to develop an IEEE wireless standard on WBAN. In this paper, we first review the main activities of TG15.6 with the updated status. Then, we present a prototype WBAN system that is implemented by using ultra-wideband technology. Multi-hop mechanism is adopted to guarantee reliable connection. Finally, we describe an experimental system that uses the developed WBAN system by combining with satellite communication in supporting remote medical treatment and healthcare. In case of less of medical resources such as in emergency, in rural or isolated areas, such a system is important in sending the corresponding biosignal to a remote hospital in real time to help patient management. The relative delay of WBAN data delivery via satellite is measured which is dependent on the satellite link capacity.     

Point-spread function for a rotationally symmetric birefringent lens

Imaging properties of a birefringent lens, in which the fast (or the slow) axis is distributed in the radial direction whereas magnitude of birefringence varies as a quadratic function of the pupil radius, are investigated by calculating a point-spread function. It is found that the point image is analytically described by using the Lommel function as well as the zero-order Bessel function, and a localized intensity null surrounded by bright regions in all directions can be realized at a geometrical focus under certain conditions. The magnitude of birefringence that is tolerable in image formations is also discussed, assuming that the lens is applied to microlithography.     

Modeling Party Support of Japanese Voters in the Early 1996

This article investigates factors that influenced Japanese voters in the early 1996 in determining which political party to support. Proportional-odds model, a model which retains ordinal nature of political hues or ideologies of the Japanese political parties, is fitted to the data. Samples with answers “I do not know” to the questions are treated as missing. The EM algorithm enables us to incorporate the samples with missing-values. We found that determining which party to support is a purely political decision for Japanese voters based solely on their ideologies and attitude towards the current cabinet, not to be influenced by their geographical profiles nor financial situations. Missing-value problem were found not to be ignored in the sense that marginally significant or insignificant explanatory variables can easily turn otherwise when the same model is fitted only for the data with no missing-values.

     

Illumination normalization with time-dependent intrinsic images for video surveillance

Variation in illumination conditions caused by weather, time of day, etc., makes the task difficult when building video surveillance systems of real world scenes. Especially, cast shadows produce troublesome effects, typically for object tracking from a fixed viewpoint, since it yields appearance variations of objects depending on whether they are inside or outside the shadow. In this paper, we handle such appearance variations by removing shadows in the image sequence. This can be considered as a preprocessing stage which leads to robust video surveillance. To achieve this, we propose a framework based on the idea of intrinsic images. Unlike previous methods of deriving intrinsic images, we derive time-varying reflectance images and corresponding illumination images from a sequence of images instead of assuming a single reflectance image. Using obtained illumination images, we normalize the input image sequence in terms of incident lighting distribution to eliminate shadowing effects. We also propose an illumination normalization scheme which can potentially run in real time, utilizing the illumination eigenspace, which captures the illumination variation due to weather, time of day, etc., and a shadow interpolation method based on shadow hulls. This paper describes the theory of the framework with simulation results and shows its effectiveness with object tracking results on real scene data sets.