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The localization accuracy of traditional APIT localization algorithm for wireless sensor network depends on the Approximate Perfect Point-In-Triangulation Test (APIT), and the localization error can be promoted in sparse network. We design one improved localization algorithm (RTD-APIT) based on APIT by using the RSSI and the triangles deformation. RTD-APIT uses the RSSI to improve the APIT for achieving the preliminary location of unknown node, and expand or deform the triangles for solving the Point-In-Triangulation (PIT) problem well and enhancing the localization. Simulation shows RTD-APIT can reduce the localization error effectively, and it also promote the localization coverage.

Mo-Cu alloy with high density can be fabricated at lower sintering temperature by high-energy ball-milling mechanical-alloying method and adding activation element. The rule of change of microstructure and its effect on the thermal expansion coefficient are studied. It is found that the holes in the Mo-Cu alloy sintered at lower temperature disappear, and Mo and Cu distribute uniformly. The Mo particles are fine-grained, and distribute uniformly in the Cu particles using the mechanical-alloying method. The change of thermal expansion coefficient with temperature is in accordance with the effect of adding activation element. There is a minor inflexion in the thermal expansion coefficient curve at 500°C. The change of thermal expansion coefficient with temperature is the same as 95% Al2O3 sealing material. Thus, the thermal property between Mo-Cu alloy and 95% Al2O3 match well.

The olivary flowmeter, a new type of differential pressure flowmeter, was presented. Its pressure loss was explored through experimental research. The experimental medium is diesel. In the condition of the same effective area of circulation, the pressure loss of the olivary and the orifice plate flowmeter was compared. As a result, the pressure loss of the olivary flowmeter is 14.9% of the orifice plate flowmeter at most, 7.2% on average. The olivary flowmeter can reduce energy consumption.

Natural ventilation is an important role to improve the residential building indoor thermal environment in summer. This paper use Energy Plus to simulate indoor thermal environment and use CFD to simulate indoor air flow for Xi’an residential building, analysis the influence that different ventilation mode for indoor thermal environment factors. Then with the simulated result of PMV-PPD value to estimate indoor thermal comfort. Proved night ventilation is necessary in residential building in Xi’an and effectiveness to improve indoor thermal comfort.

It is widely accepted around the world that degree days should act as the measurement of HVAC energy in a given place. This paper makes use of the temperature data from 1985 to 2004 from 96 meteorological stations in Shaanxi Province. Based on the daily average temperature in some cities, counties and districts in Shaanxi, we work out the degree days. We divide different zones according to the normalized degree days from 1995 to 2004. In this paper, we analyze the distribution of degree days in Shaanxi, the changes in every decade, and the monthly distribution of degree days in Yulin, Yan’an, Xi’an, Hanzhong, as well as the changes of value in 20 years in Xi’an. At last, we figure out that Shaanxi has spread out its terrain in two climate zones: one is the cold zone; the other is the hot summer and cold winter zone. The HDD18 value has declined continuously in 20 years, and it drops 194.8°C•d/10a every year; meantime the CDD26 has ascended by 28.1°C•d/10a. In all the cities, the HDD18 value is the highest in January, and lowest in July. In the past 20 years in Xi’an, HDD18 value has dropped by 25.0°C•d/a, and the CDD26 has risen by 5.2°C•d/a, which are the highest among those cities.

There are serious energy-saving problems in cold region of rural residential buildings. On one hand, it needs the higher levels energy because of the particular climatic conditions, on the other hand, people in cold regions lack of energy-saving consciousness and technology. Through analyzing the rural residential building status and existing energy-saving problems in cold region of China, the author discussed and summarized the energy-saving design methods of rural residential building in cold region from three aspects, including the energy-saving of residential building size design, the energy-saving of building envelope structure design, and use of renewable energy. The research provides a reference for promoting socialism new rural reconstruction in China.

As social and economic development in China，building scale and medical devices have greatly improved in hospitals, and patients and medical staff are requiring a more and more comfortable indoor environment. All these lead to rising energy consumption of hospital buildings. How to save energy and reduce consumption on the basis of keeping medical quality? This paper takes studies on energy consumption of hospitals in Shaanxi province. First of all, questionnaires about energy consumption of hospitals were carried out. Total energy consumption and electricity consumption were analyzed and energy consumption law was summarized. Then, quota principle and quota method of energy consumption were explored, and energy consumption quota of hospital buildings in Shaanxi province was established. This research contributes to energy-saving of hospital building and provides reference for other public buildings in Shaanxi province.

Tin - Titanium alloy has been prepared by powder metallurgy method. By the way of preparing pre-alloyed metal and fully fine to ultra fine powder, optimizing sintering techniques, the Problem of enrichment of titanium from the alloy has been solved, the Tin - Titanium alloy with its homogeneous distribution elements has been made. Then the Tin-titanium strap has been processed successfully. In this paper, the key process to make Ti -Titanium alloy by Powder Metallurgy Method is introduced. The factors which affect the uniform components of the alloy have been mainly analyzed, such as ultra fine powder of pre-alloyed metal, diffusing sinter at lower temperature .etc. The results indicate that powder metallurgy with ultra fine powder additive and diffusing sinter at lower temperature is the efficient method to solve titanium element in the alloy segregate.

To analyze the transient response of transformer windings under very fast transient over-voltage (VFTO), multi-conductor transmission line (MTL) model based on the representation of transformer windings by its individual turns are established. Space discretization is needed for solving the time-domain telegraph equations of MTL. To calculate the voltage distributions along transformer windings, through combining the compact finite difference (CFD) theory and the backward differentiation formulas (BDF). Simulation software ATP is introduced, and the simulation results demonstrate that the proposed approach is feasible.

The numerical calculation model with compound insulation of transient electrical field is established. The types of voltage applied on the valve side winding of the converter transformer are complicated and the insulation is more prominent. So the simplied calculation model of the valve side winding of the converter transformer is established. The distribution characteristics of electrical field of the valve side winding of the converter transformer is analyzed and electric field in different electrical conductivity and permittivity are calculated under AC high voltage, DC high voltage, AC superimposed DC voltage, polarity reversal voltage. Under all kinds of high voltages, the maximum electric field strength is calculated and analyzed. Some important influence factors for electrical field distribution are also discussed in this paper.

A three-dimensional nonlinear elastic-plastic finite element method had been developed to study the bending behavior of piles subjected to axial load and lateral soil displacement. The influence of the lateral soil displacement, axial load level and the cap of piles were studied and variety law of the bending behavior was presented. The study showed that the bending moment increased with the lateral soil displacement. The displacement at the soil surface and the maximum bending moment of pile also increase with the axial load. The cap of piles has a great influence on bending moment and displacement of pile group.

Partial current rules of the National Standard of Fire Code are disjointed from the current development of large commercial building; as a result, part of the design cannot be carried out according to the specifications. The new digital fire control design method can solve this difficulty. This paper is to take a large commercial building as an engineering example, introducing the new design concept of “independent fire protection unit” and “quasi-safety area” to adjust the program; then, on the basis of fire safety engineering principles, it uses the computer-assisted method to predict and assess the dangers of fire and the safety of evacuation, and thus demonstrating the feasibility of this method.

There is abundant renewable energy in Shaanxi province of China. Renewable energy buildings utilization plays a very important role in the sustainable development of Shaanxi Province. Developing scheme for building applications of renewable energy in Shaanxi province was explored in this paper. Distribution and storage of renewable energy in Shaanxi province was introduced firstly. Taking into account of energy requirements and utilization levels, suitable areas were proposed in this paper, where various kinds building application technology of renewable energy can be promoted. The development priorities in building applications of renewable energy were also discussed. Finally, building applications objectives of renewable energy from 2011 to 2015 in Shaanxi province was proposed. This research will provide reference for building applications of renewable energy in Shaanxi province of China.