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This paper discusses the thermal management of the structure design of an anti-freezing building in an HVDC substation. The CFD simulation has been carried out under the condition of natural wind velocity with the influence of the air cooler. The result shows that the hot air reflux ratio is proportional to natural wind velocity when the anti-freezing building has a certain height; the hot air reflux ratio is proportional to the anti-freezing building height when the natural wind is in a certain velocity. Through detailed cost analysis, the most optimal height of anti-freezing building is about 6 meter. Based on the thermal analysis, rational design of anti-freezing building can effectively prevent hot air recirculation, and the air cooler inlet temperature decreases 3°C.

A micro-pattern gas detector named leak microstructure (LM) has been studied. A new chemical electrolytic technique is introduced to make perfect shaped LM needles with very sharp tips, and this method may be developed to make LM array detectors in batches. The experimental results are presented for both a single needle LM detector and a small LM array detector. The gas gain is up to 105 by calculation from the waveform. Good gain stability and uniformity are achieved. The light emission from the needle tip is also measured in Ar/CF4(95/5) gas mixture. The result shows a promising application for imaging.

Silicon photomultipliers (SiPMs) are a new generation of semiconductor-based photon counting devices with the merits of low weight, low power consumption and low voltage operation, promising to meet the needs of space particle physics experiments. In this paper, comparative studies of SiPMs and traditional vacuum photomultiplier tubes (PMTs) have been performed regarding the basic properties of dark currents, dark counts and excess noise factors. The intrinsic optical crosstalk effect of SiPMs was evaluated.

A kind of thick GEM-like gaseous electron multiplier (THGEM), which is mechanically an expansion of the GEM with its various dimensions being enlarged, is studied. The leak current of THGEM plates is measured. The effective gain and energy resolution of a single THGEM are studied with a source of 55Fe, and the effective gain of the single THGEM versus the electric field strength in the induction region is investigated. The results show that the leak current of THGEM plates is less than 200 pA. In an atmospheric-pressure standard gas mixture, 8×103 effective gain and about 32% energy resolution can be reached for the single-THGEM detector.

The CsI(Tl) crystal modules of the Beijing Spectrometer III (BESIII) electro-magnetic calorimeter (EMC) were designed and assembled through Monte Carlo simulation and experiments. After the assembly was finished, the performance of each crystal module was tested by cosmic rays. All crystal modules were found to work well before the installation of EMC.

In the modern times, the highway management needs better information supporting system to connect all these Online Transaction Processing Systems, to meet the integrated data analysis need of scientific management. Because of the deficiencies of traditional data management information system, the data warehouse technology has been used to organize and analysis the massive datas and provide a basis decision-making supporting. Combination of the highway management practices, in this paper the provincial highway management data warehouse architecture was constructed and the data model design method and strategy were put forward, and the subject, data granularity of data warehouse for highway management were analysised. In finally the meta-data organize and its implementation program were discussed. With the application of data warehouse technology in highway management, which will promote the analysis of management decision-making of China's highway modernization, scientific and information process.

In wireless communications, blind equalization plays an important role in combating inter-symbol interference (ISI) introduced by multipath fading wireless channels, and its main performance criterions are residual mean square error (MSE), convergence speed, and complexity. In this paper, an efficient blind decision feedback equalization algorithm suitable for wireless communication channels is proposed. The performance of the new method is compared to traditional blind decision feedback algorithm by means of computer simulations, and the simulation results confirm the validity of the proposed method.

Aiming to overcome deficiencies of existing DSS for VRP, which cannot meet with real-time and online routing and scheduling, a new knowledge representation approach to efficiently eliciting domain knowledge of the vehicle routing problems (VRP) and transforming this elicited knowledge into a machine usable format is proposed. According to the characteristics of VRP, the approach contains three steps: confirming problem rarr identifying problem structure rarr representing problem knowledge. The approach is demonstrated in detail through case study after analyzing principles of it. This approach sets foundations for consequent modeling and solving of VRP and can be used as reference by DSS for any types of VRP