Electromagnetic transients in the control system of output parameters of a solar power plant in Tajikistan Central Asia region

At present, as the demand for electricity increases in all sectors, there is an urgent need to introduce alternative renewable energy sources into modern energy systems. Renewable energy sources, which consist of solar (photovoltaic, PV), wind and hydro power, are key alternative sources of “green energy’’ energies, but it can also be used to produce “green” hydrogen. Thanks to scientific and technological progress, the cost of photovoltaic solar radiation converters is constantly decreasing at a high rate, which makes it possible to build solar power plants of sufficiently large capacity. In the coming decades, solar energy will become an incentive for the economic development of countries that have the maximum “solar” resource. The Republic of Tajikistan is one of these countries with a high potential for solar energy.The article presents an analysis of the resources and potential of solar energy in the Republic of Tajikistan. The study of electromagnetic transients in networks with photovoltaic solar power plants is performed. The main equations, simulation model and calculations of transients are presented, taking into account changes in voltage on DC buses. An algorithm for controlling the system of automatic control of output parameters is proposed. The analysis of dynamic and static modes in parallel operation of a solar power plant with the grid is carried out. A block diagram and computer model is constructed in the MATLAB package together with Simulink and Power System Blockset.     

三门核电土石方工程中深孔爆破法的应用

浙江三门核电平基工程中采用深孔台阶爆破进行土石方开挖,对底板的平整度和完整性有很高的要求,超挖不得超过20cm,不容许欠挖。为此,根据可爆性对开挖区内的岩石进行分级,分别采用不同的钻爆参数,同时采取了预留保护层爆破、无超深爆破、底部空气间隔装药等技术措施,确保了底板的开挖质量。     

Rapid screening of DON contamination in whole wheat meals by Vis/NIR spectroscopy and computer vision coupling technology

This work intends to develop an online experimental system for screening of deoxynivalenol (DON) contamination in whole wheat meals by visible/near-infrared (Vis/NIR) spectroscopy and computer vision coupling technology. Spectral and image information of samples with various DON levels was collected at speed of 0.15 m s⁻¹ on a conveyor belt. The two-type data were then integrated and subjected to chemometric analysis. Discriminant analysis showed that samples could be classified by setting 1000 μg kg⁻¹ as the cut-off value. The best correct classified rate obtained in prediction was 93.55% based on fusion of spectral and image features, with reduced prediction uncertainty as compared to single feature. However, quantification of DON by quantitative analysis was not successful due to poor model performance. These results indicate that, although not accurate enough to provide conclusive result, this coupling technology could be adopted for rapid screening of DON contamination in cereals and feeds during processing.     

Comparison of children’s gaming scores to NEPSY-II scores: Validation of computer games as cognitive tools

This exploratory quantitative study compared schoolchildren’s scores on 15 computer games to their scores on the neuropsychological test, NEPSY-II, to determine whether these games utilize predicted cognitive skills. Forty-three children aged 7–12 from different ethnic groups participated in this study. There was an almost equal split between girls and boys, some of whom reported mild learning difficulties. Many a priori predicted correlations were confirmed, with a medium to high effect. Eleven games shared their highest correlation with one or more of the predicted cognitive skills as measured by the NEPSY-II, which provided evidence that these computer games use specific cognitive functions. This suggests that similar computer games could be used to assess, practice, or monitor cognitive skills among schoolchildren.     

AppFusion: Interactive Appearance Acquisition Using a Kinect Sensor

We present an interactive material acquisition system for average users to capture the spatially varying appearance of daily objects. While an object is being scanned, our system estimates its appearance on‐the‐fly and provides quick visual feedback. We build the system entirely on low‐end, off‐the‐shelf components: a Kinect sensor, a mirror ball and printed markers. We exploit the Kinect infra‐red emitter/receiver, originally designed for depth computation, as an active hand‐held reflectometer, to segment the object into clusters of similar specular materials and estimate the roughness parameters of BRDFs simultaneously. Next, the diffuse albedo and specular intensity of the spatially varying materials are rapidly computed in an inverse rendering framework, using data from the Kinect RGB camera. We demonstrate captured results of a range of materials, and physically validate our system.     

Nail clipper ergonomic evaluation and redesign for the elderly

This study designs and evaluates a new nail clipper for the elderly using ergonomic methods. The nail clipper usage problems and requirements were collected first. After requirement analysis we applied ergonomic simulation in redesigning the nail clipper and developing a pedal plate. A usability test was conducted to evaluate both typical and newly developed nail clippers using 20 elder participants. The dependent measures were the total number of nails clipped, completion time and discomfort and satisfaction subjective ratings. The experimental results indicated that the newly developed nail clipper was superior to the typical one in subjective ratings for discomfort and satisfaction. The performance of the newly-developed nail clipper is similar to that of the typical clipper. Some important nail clipper design implications for the ageing population are discussed.Relevance to industryWith the increase in the elderly population, problems caused by aging have gradually emerged. Aging may cause the elderly inconvenience in using many household objects that are not specifically designed for the elderly. Therefore, industrial designers should try to redesign household objects to enhance living quality for the elderly. This study used nail clipper design as an example to show how to apply ergonomic methods in product design.     

The use of ballistic movement as an additional method to assess performance of computer mice

This study investigates an additional method for independently evaluating performance of speed and accuracy of computer mice, based on five parameters of the initial submovement when aiming at a target. This first submovement is known to be carried out in a ballistic manner and hence the Fitts-type aiming movement may be studied by means of the established relationships for ballistic movement. To test the ballistic movement method, eight participants used four different computer mice to execute ballistic movements and Fitts-type aiming movements. Regression tests showed that the Fitts movement time was well correlated with the time and stopping-variable error of ballistic movement, implying that measuring ballistic movement parameters can predict the performance of Fitts-type aiming movements. More importantly, the use of ballistic movement method allows independent assessments of the speed and accuracy, providing additional information for input devices assessment and designs.Relevance to industryThe study illustrates the close correspondence between input device evaluation using the proposed ballistic movement method and Fitts' law. The ballistic movement method allows independent measures of speed and four types of accuracy, which should benefit input devices assessment and designs.     

Identification of hydrogen permeability parameters of membrane materials in an aggregated experiment

The study of the hydrogen permeability of materials for membrane-based separation/purification technologies employs a variety of experimental methods with their own specific features, advantages and shortfalls. The method of penetration with vacuum pumping allows determining the diffusion coefficient from so-called lag time. The accuracy of the estimation depends on the degree of proximity to the DLR (diffusion limited regime) mode. The method of “communicating vessels” is more sensitive to surface processes. The thermal desorption (TDS) technique permits “scanning” the material dynamically across a wide range of temperatures. “Separate” application of these methods leads to a situation where the materials studied are in fact somewhat different (for example, due to different impacts on the surface), and significant differences in parameter estimates ensue. This paper suggests and implements a technique for a combined three-stage ‹‹penetration (with and without vacuum pumping)+TDS›› experiment and the corresponding mathematical toolkit. The informative capacity of the experiments and the accuracy of the estimation of hydrogen permeability parameters (adsorption, dissolution, diffusion and desorption) of the membrane materials under study are thus enhanced.