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While design optimization of buildings seeks to improve energy efficiency and, thus, leads to greenhouse gas emissions reduction, the thermal performance of buildings can be compromised. Thermal performance is an important aspect as it directly affects the health and well-being of occupants. This study aims to investigate using a simple simulation tool to examine the correlation between a set of building physical design parameters such as orientation, shading and shape, optimization of which helps to make a positive impact on the thermal performance of the building in a cold climate zone. The thermal performance simulation tool Passive Design Assistant (PDA) was used to build a simulation model and test the interdependence between the design parameters and thermal performance. The results indicate that modifications of building’s parameters such as orientation and shape or the addition of shadings lead to improvements of the internal thermal temperature, heat gain and loss, hence the optimal parameters should prevail. A case study for cold climate is analyzed, in Nur-Sultan, Kazakhstan, the optimal orientation for the squared building is 30° from East to South (building rotated 120°) and the optimal building’s shape is rectangular, which attracts up to 2.6 times higher solar gains than the square one. Moreover, the use of shadings can regulate the internal temperature of the building by 2 °C. General recommendations based on the findings are made and could be considered in the earlier stage of building design and construction processes.

According to the demand of new measuring AC high-voltage technology based on the development of power network, this paper proposes an AC high -voltage measuring system using high voltage standard capacitor based on the analysis of the existing AC high-voltage measuring technology, the working principle of the AC high-voltage measuring system is analyzed in detail, and the experimental research on the steady state characteristic and frequency characteristic of the AC high-voltage measuring system is made, at the same time, the possible errors are analyzed in detail. The AC high-voltage measuring system meets the technical requirements of high-voltage signal acquisition in the power system, at the same time, meets the requirements of AC high voltage measurement when the frequency is not more than 2500Hz, and has certain practical value..

In this research, a purification approach using nitric acid leaching at thermal closed system was developed to improve the porous structure of raw diatomite by removal of impurities from its surface and clogged pores. The feasibility and efficiency of this approach were determined by XRF for chemical constitution of diatomite, SEM for morphology and BET for specific surface area of purified diatomite. The investigations indicated that the content of SiO2 was in order of 85.14% for raw diatomite and 98% for purified diatomite, the content of Fe2O3 decreases after purified; the integrity of the porous structure was confirmed by SEM, and increase in specific surface area from 18m2·g-1 to 36m2·g-1.

This paper describes the basic structure of the current comparator used for high voltage insulation measurements. Further applications for the current comparator in high voltage insulation are investigated and developed. A measuring system for the measurement of harmonics in the loss current of water tree aged insulation is described, as well as the principles to measure partial discharges with the current comparator bridge. A new system for the measurement of the DC component in the leakage current of insulation is de1veloped and presented. The results of experiments on XLPE cable insulation are also given.