Applied Mechanics and Materials Vol. 737

Abstract: World population is steadily increasing and it is estimated to reach 9 billion in 2050. Moreover, 72% of people live in big cities and the buildings energy requirement is growing, reaching the 45% of the total energy amount.This paper presents of a building energy efficient properly designed to realize a solar-powered house that is cost-effective, energy-efficient, and attractive. The study applied a methodology which is able to identify the best building plant configuration under a technical, economical and environmental point of view. It has been demonstrated that the proposed plant allows to reduce the fossil fuels consumption compared to a plant conventionally employed, with a proportional reduction of the greenhouse gas emissions of about 30% per year.

Abstract: This paper takes typical Hakkas circular earth buildings as research object. Based on field survey and literature survey, the authors have extracted the surroundings, architectural forms, and material language of typical circular earth building. And, incorporated with present landscape language, they have come up with the pattern language of modern Hakkas landscape for further directing of the related designs.

Abstract: In order to study the human thermal adaptation in Tibetan dwellings of Kangding Tibetan Autonomous Prefecture, Sichuan Province, selected 4 dwellings in Tagong and Zhonggu village as the research objects and used the method of objective thermal environment parameters test combined with the subjective questionnaire, and got a total of 119 valid samples, the data analysis results show that indoor air temperature in this area was low, average clothing insulation was 0.75clo and it correlated with outdoor temperature was stronger than that with indoor temperature. The change rate of human thermal sensation changing along with outdoor temperature was 0.113 per temperature and it was 0.147 per temperature changing along with indoor temperature. Thermal neutral temperature was 18.5°C and preferred temperature was 20.65°C, neutral temperature was lower than preferred temperature but closer to average indoor temperature (17.36°C).

Abstract: This study aims to assess the influence of greenery shading and transparent surfaces on historical building’s energy demand under a retrofit point of view. To achieve this goal, the energy requirement of the whole building has been considered. In order to improve buildings energy efficiency several simulations have been performed. In particular, the effects of some interventions related to different windowed elements, characterized by progressively improved thermal properties, have been taken into account.

Abstract: Abstract: On the condition of protecting the critical load, it is necessary to restore the service of outage area without fault as soon as possible after the occurrence of fault in smart distribution system. A fast service restoration method is proposed for medium-voltage distribution system with distributed generations, which combines intentional islanding of DGs for network reconfiguration. Under the condition of safety limits, the out of service areas are achieved maximization of restoration, making full use of DGs. The whole process of restoration is regarded as a multi-stages decision problem, and divided into four stages. Compared to the existing algorithms, this method can effectively avoid the time-consuming and search results problems, and the simulation results are better. The effectiveness and practicality of the propose approach is demonstrated by simulations on a PG&E 69-nodes system with DGs.

Abstract: In order to relieve the problem that too much pollution is released by traditional power supplies, recycled energy is introduced around the world and is used in the form of distributed sources and organized in the structure of microgrids. When a fault happens in the main grid, the microgrid should detach from it to keep its own normal functioning. And island partition is required to keep microgrids working stable.In this study, we propose a new island partitioning strategy which is based on voltage stability margin. To make comparison, another island partitioning strategy based on electrical distance is introduced. We also present a case on the basis of CIGRE network to compare the outcomes by two strategies. Results show the strength of the proposed strategy.

Abstract: Power quality disturbance detection and identification is the prerequisite and basis for the power quality management and control. This paper presents a new power quality disturbance detection and classification method. Firstly, the time-time transform is applied to power quality disturbance signal analysis. According to spectrum analysis results of the diagonal elements of time-time transform matrix, a preliminary judge about whether the disturbance signal contains harmonics and inter harmonic was given. For disturbances with non-harmonics, based on time-time transform modulus matrix diagonal sequence, the beginning and ending time of the disturbance is located, and the disturbance amplitude is calculated. For the disturbances which contain harmonics, time-time transform is perform twice to get the row mean value curve and the column mean value curve, which are required by disturbance time location and amplitude measurement. Finally, disturbance classification had realized by using rule tree. Simulation results reveal that this method is very robust and adaptable, which can identify transient power quality disturbance with minor magnitude under noisy environment, and the recognition rate is satisfactory.

Abstract: Modern wind turbine technology has been a great improvement over the past couple decades, leading to large scale wind power penetration. The increasing penetration of wind power resulted in emphasizing the importance of reliable and secure operation of power systems, especially in a weak power system. In this paper, the main wind turbine control schemes, the wind penetration levels and wind farm dynamic behavior for grid code compliance were investigated in the Penghu wind power system, a weak isolated power system.

Abstract: With the rapid expansion of the grid, how to solve the security and stability of power system has become a hot problem. As a power system after a serious accident the necessary security measures, black-start programs are expected to play an extremely important role in reducing the loss of equipment and user outage and decreasing the outage time. The present paper proposes a series of advantages about distributed generator (DG) and raises evaluation indexes of DG in black-start. The fuzzy hierarchical model is built based on the general steps of fuzzy decision theory. According to the concept of triangular fuzzy number, considering the indexes of which the weight value is judged by means of trapezoidal fuzzy number complementary judgment matrix. Finally, by actually case anglicizing, the paper demonstrates the scientific nature, effective and easy to operate of the method. And a new decision-making method for the optimal DG start-up sequences based on fuzzy AHP is proposed.

Abstract: Analyzing the characters and abstracting the system model of the distribution automation system, information security test-bed of distribution automation is designed. Meanwhile, information security test and evaluation framework is proposed based on the lifecycle of distribution automation system. The evaluation activities and the testing methods are analyzed and key problems and solutions of information security evaluation and reinforcement requirements for distribution automation system are introduced. The work in this paper can effectively support the information security protection of distribution automation system, and can provide reference for other power industrial control systems.