In this paper, the grid-connected photovoltaic system in Tochigi prefecture, Japan, is presented, and its technical and economic performance after eight years is evaluated. The system has a peak power of 40.1 kWp and has been in operation since 2012. The entire electricity generated by the system was fed into the state grid. The system is suitably monitored for one year (2019) and analyzed using the parameters developed and defined in the standard IEC 61724-1 by the International Electrotechnical Commission. The system’s different parameters included array yield, final yield, capacity utilization factor, and performance ratio of the system. An analytical model with solar irradiation obtained from Power Data Access Viewer was developed to investigate and evaluate the efficiency of the system monthly and annual energy generation by comparing the simulated and measured energy acquired from the inverter. A positive linear relationship is observed between solar irradiation data obtained from Power Data Access Viewer and the grid-connected photovoltaic system energy injected into the utility grid. While an annual total of 48,521 kWh of energy was expected to be generated, 38,071 kWh was generated and injected into the utility in 2019. This study also introduces and explains the mechanism of the Feed-In-Tariff system in Japan. The performance of the grid-connected photovoltaic system under this study was compared with that of other systems installed across the globe.

Japan's largest platform for academic e-journals: J-STAGE is a full text database for reviewed academic papers published by Japanese societies

This paper presents an experimental investigation on photovoltaic array (PV array) power output affected by partial shading conditions (PSCs). An experiment setup of a PV array with a series configuration using 2 $\times$ 4 photovoltaic modules (PV modules) was built. The power output loss due to the shading effect on the first photovoltaic cells (PV cell) connected with bypass diodes of each photovoltaic module, installed in the PV array in the horizontal direction, was evaluated. Depending on the direction of the sun relative to the PV array configuration, the shading percentage was measured during the test and recorded the current and voltage of the PV array. The performance evaluation of the PV array configurations is referred to with respect to the values of maximum power voltage, the maximum power current, maximum power output, power output losses and fill factor (FF). The experimental results show that 44% shading of the first PV cells affects PV array power output loss by more than 80%.

Using an agent-based traffic models, we analyze the manner in which the number of platoons within a traffic system is correlated with the appearance of traffic jams. Two definitions of a platoon are proposed and verified using agent-based simulations to find the one that provides the most realistic representation of traffic behavior in a stochastic model. We observe that traffic jams are closely related to the convergence of multiple platoons into a single platoon containing all the agents in the model. We also observed that at high-density, traffic system maintains a metastable state when it has multiple platoons in it. A traffic jam occurs when these multiple platoons are merged into a single platoon, which is equivalent to the concept of an infinite cluster in percolation theory.

In this paper, to analyse the rider's effects on the motion of a motorcycle, we model a rider–motorcycle system by taking into account the leaning motion of the rider's upper torso and his/her arm connection with the handlebars. The nonlinearity of the tyre force is introduced by utilising hyperbolic tangent functions to approximate a Magic Formula tyre model. On the basis of a derived nonlinear state-space model, we analyse the effects of not only the rider's arms but also his/her postures during steady turning by simulations. The rider's postures including lean-with, lean-in and lean-out are realised by adding the lean torque to the rider's upper torso. The motorcycle motion and the rider's effects are analysed in the case where the friction coefficient of the road surface changes severely during steady turning. In addition, a linearised state-space model is derived during steady turning, and a stability analysis of the rider–motorcycle system is performed.