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March 30,2011
Volume 4,Issue 6
Pages -
Subject Area:Geographic Information System,Energy Systems Engineering, Energy Economy,Energy Calculation and Measurement,Energy Storage Technology,Energy-saving Technology

Title: The advances on theory and method of geo-ontology in China

Authors: LI Hongwei
PP: 564-575
Abstract: This paper systematically summarized the geo-ontology and geographic information classification, the construction of geo-ontology, the organization,management,expression of spatial data based on geo-ontology, the geographic information retrieval and geographical knowledge query based on geo-ontology, the geographic information sharing and interoperability and semantic integration based on geo-ontology, geographic information service and their combinations, space-time geo-ontology and reasoning, geographical spatial semantic grid etc. for 10 years. The paper summarized these outstanding works of Chinese scholars in the fields. Finally, analyzed and predicted existing problems in the research.
Keywords: geographical information system; geo-ontology; reviews; geographic information classification; semantic integration; space-time geo-ontology; semantic grid

Title: Research of influence on mining depth to coal and gas outburst

Authors: LI Tao, LAN Tianwei
PP: 559-563
Abstract: To study the effect of mining depth to coal and gas outburst, this paper takes two coal seams of J15 and W9-10 in Pingdingshan mine as examples, and bases on the research work such as field stress measurement, numerical simulation of rock stress, geodynamic zoning in mining area, and analyzes the difference of elastic potential energy between two seams in model region from the point of energy, then provides distribution contour of elastic potential energy of two seams roof, and calculates the elastic potential energy of two seams. It concludes that the elastic potential energy of deeper J15 coal seam is much bigger than that of shallow W9-10 coal seam, and results in the increase of possibility and strength of coal and gas outburst, therefore getting the relationship of influence between mining depth and coal and gas outburst.
Keywords: mining engineering; mining depth; coal and gas outburst; elastic potential energy

Title: Failure mechanism and controlling technology of surrounding rock in gob-side entry retaining

Authors: LI Yanqing
PP: 553-558
Abstract: By analyzing the movement characteristics of ‘cantilever beam’ and ‘lining beam’ which are respectively formed before and after main roof fracturing above gob-side entry retaining, this paper obtains that surrounding rock may occur cutting off, rotating, breaking and caving failure. And then it is proposed that anchor combined support in the roadway can reinforce coal sidewall to prevent cutting off and control roof to prevent caving, I-beam with gangue wall or filling materials support roadside and add a support point to form ‘simply-supported beam’ structure which plays a role to prevent rotating and sinking, individual hydraulic prop is used to weaken stress influence within the dynamic pressure. By the practice of Huainan and Huaibei mining area these controlling technology have been proved to effectively control deformation and failure of gob-side entry retaining and achieved good technical and economic effects.
Keywords: mining engineering; gob-side entry retaining; main roof failure; controlling technology

Title: Application of borehole camera technology for measuring relaxation zone of surrounding rock

Authors: DAI Dapeng, JING Hongwen, GENG Dongkun
PP: 548-552
Abstract: In recent years because of its ease and intuitive,borehole camera technology is increasingly used in measuring the relaxation zone of surrounding rock and has achieved fairly good results. This paper briefly describes the overall borehole camera system structure and working principle, took 11801 working face of a mine as the engineering background, used borehole camera technology to measure the thickness of relaxation zone of surrounding rock, and successfully obtained the thickness values. The result can be used for the roadway design and provides a basis for stability analysis.
Keywords: geotechnical engineering; borehole camera; broken zone; spot test; roadway

Title: Research on sequence start-up problem of heavy scraper conveyer

Authors: WU Fengbiao, LI Chunying
PP: 543-547
Abstract: The paper researched the problem of sequence start-up of scraper conveyor’s head and tail. It established the viscoelastic model of scraper chain and the dynamic finite element model of scraper conveyer sequence start-up based on the viscoelastic properties of scraper chain and derived the dynamic equation. Then, an example of scraper conveyer sequence start-up affecting on the tension of the chain was simulated. Analysis showed that the conveyor head and tail sequence start-up had great impact on the dynamic tension.
Keywords: scraper conveyer; scraper chain; sequence start-up; finite element analysis; dynamic tension

Title: Analysis on chaotic characteristic of coal and rock electromagnetic radiation

Authors: HAO Yankun, XU Fule, XIE Shaodong, YANG Bo
PP: 538-542
Abstract: The evolution of the coal and rock dynamic system can be reflected by the electromagnetic radiation (EMR) indexes. The chaotic characteristics of EMR time series can be judged by its largest Lyapunov exponent, if it has chaotic characteristics, the predictable time can be determined by the largest Lyapunov exponent of the EMR time series, and the predictive value in the predictable time can be obtained. Therefore, the EMR evolution of the coal and rock will be understood in advance. A roadway was monitored by on-line electromagnetic radiation monitor (KBD7) during the excavation. The largest Lyapunov exponent of monitored EMR time series was calculated based on method of small data sets, the results showed that the EMR time series have chaotic characteristics, EMR can be predicted in short term, the precision can be improved by eliminating interference and choosing the appropriate sample size.
Keywords: mine safety; coal and rock dynamic disaster; electromagnetic radiation; Lyapunov exponent; chaos; prediction

Title: Research status of kerosene emulsion collector

Authors: CAI Yanghui, JI Denggao
PP: 531-537
Abstract: From the problems of coal flotation in current coal washing industry, this paper led to new methods for the flotation in recent years: kerosene emulsion was prepared as collector and used for flotation. Theoretical basis of kerosene emulsion was introduced at first, then the concept of kerosene emulsion was given out, thereinto, preparation principle, preparation methods, properties, characterization methods of kerosene emulsion were mainly introduced. And then it summarized the research status and industrial application status of kerosene emulsion at home and abroad, summarized and analyzed the floatation effect of kerosene emulsion and the problems of research of kerosene emulsion. At last, development prospect and goals of industrial applications of kerosene emulsion were given out.
Keywords: technology of mineral processing; kerosene emulsion; reviews; flotation; collector

Title: Research on the spontaneous combustion characteristics of typical coal seams in Gushan

Authors: SUN Shumin
PP: 526-530
Abstract: A series of thermo-gravimetric experiments are conducted, in which one coal sample from coal layers containing fusain and the other from coal layers without fusain are tested, both of them are taken from working face 065-2 in Gushan mine. Based on the theory of thermal analysis kinetics, thermo gravimetric (TG) curves and derivative thermogravimetry (DTG) curves in experimental results are analyzed and four characteristic temperature points significant to the oxidation process of coal, such as critical temperature and ignition temperature, are found out in each group of curves. Then TG data are correlated in the view of different kinetic models and the kinetic parameters of two coal samples are calculated. The results show that oxidation and thermal decomposition of typical coal samples complies with kinetic mechanism of the first order chemical reaction, and that coal containing fusain has a low ignition temperature and a stronger tendency of spontaneous combustion, which need to be monitored and controlled primarily.
Keywords: thermal analysis kinetics; spontaneous combustion tendency; characteristic temperature; activated energy

Title: Displacements recognition of storage tank and calibration of tank capacity charts based on integration

Authors: FAN Yu, WANG Yunan, WANG Junjie, CAO Qi
PP: 512-525
Abstract: In this paper, to identify the displacements and tank capacity charts calibration, the oval crew-cut oiltank computing model, round ball top oiltank computing model and least-square searching model are established. By integrating the section, the paper is first concerned with the function expression of oil level height h and storage volume V in the crew-cut oil tank, when longitudinal angle α varies from 0 to 4.1 °. When the round ball top is sloped, this paper utilizes two special ideas to compute the volume of round ball top and finally to obtain the expression V with respect to parameter α and parameter β and h. In least-square searching model, the paper introduces the concept of the total deviation F (α, β), in which the solving problem of the parameter α and β becomes an optimization problem. By gradually narrowing parameter scope, the accuracy can be improved and the optimal solution can furthermore be presented. With the aid of Matlab, this paper finally presents error correction function of three models. Error analyses indicate that error correction function is mainly related with oil height h, parameter α and parameter β. In addition, it is influenced by temperature T, as the oil volume is larger and the temperature is higher.
Keywords: energy calculation and measurement; integration; tank capacity charts; least-square method; displacements recognition; error analysis

Title: Study on the water vapor permeation characteristics of PTFE membrane under freeze drying

Authors: ZHOU Zheng, XU Mengjie, WANG Bo, ZHANG Shaozhi, CHEN Guangming
PP: 505-511
Abstract: Polytetrafluoroethylene (PTFE) membrane may be chosen as the material for making the freeze-drying bag. In this paper, the water vapor permeation coefficient for a specified PTFE membrane was estimated by experimentally studying the freeze drying processes of pure water and lyophilization buffer solution in a glass vial and a special blood bag. According to the calculation of freeze drying time needed, the mass transfer resistance of the specified PTFE membrane was judged to be too high to be used for making the freeze-drying bag.
Keywords: energy calculation and measurement; polytetrafluoroethylene membrane; freeze drying; water vapor; permeation; platelet

Title: Exergy analysis of a DMR cycle of LNG

Authors: SHU Dan, SUN Heng
PP: 502-504
Abstract: Simulations and exergy analysis of a double-stage mixture refrigerant (DMR) cycle of liquefied natural gas (LNG) plant was carried out. The flow process not only has relative high energy efficient, but also decreases the vapor-liquid separation process, which simplify the operations of the plant. Exergy analysis indicates that the compression process is the main part in the while exergy loss, which acount for about 65.59%. The exergy losses of heat transfer process in the cold box only acount for about 19.51% which dues to the minor temperature differences. Besides, J-T process contribute 14.9% of the exergy losses. How to reduce the exergy losses during the compression process is the problem needed to be research.
Keywords: oil and natural gas energy; liquefied natural gas; double-stage mixture refrigerant; simulation; exergy analysis

Title: Short-term wind speed forecasting method for wind farms

Authors: GONG Songjian, YUAN Yuhao, WANG Li, ZHANG Guangming
PP: 496-501
Abstract: This paper describes three kinds of wind speed forecasting models, namely the time-series model, BP neural network model and wavelet neural network combined model. Time-series ARMA model and BP neural network model are commonly used models in the wind speed forecast, in order to improve prediction accuracy, wavelet neural network combined model has been taken into account. The three methods in the short term wind speed forecasting have been studied and compared, and wind speed from different samples has been analyzed, the results showed that: if the wind speed is relatively stable, it is desirable to use BP neural network model to predict; if the wind speed fluctuates too large, it is desirable to use wavelet neural network model in the prediction. In the actual application, it is proper to use the method which is suitable for the circumstance, to select the appropriate model in order to obtain the optimal prediction.
Keywords: control theory and control engineering; wind speed forecasting; time series; neural network; wavelet analysis

Title: Determination of dissociation heat of hydrates with additives

Authors: SUN Zhigao, LIU Chenggang, ZHOU Bo, HUANG Haifeng, XU Lezhong
PP: 493-495
Abstract: A set of visible high-pressure fluid measurement system is used to measure hydrate formation conditions of synthetic natural gas (mixture of methane, ethane and propane) in aqueous solutions. The experimental results show that higher temperature, higher equilibrium pressure, and hydrate equilibrium pressure increase with the increase of ethylene glycol at the same temperature. The dissociation heat of hydrates with additives is calculated using Clausius-Clapeyron equation based on the hydrates formation conditions. The results show that hydrate dissociation heat reduces with the increase of ethylene glycol. There are two factors for the result: one is hydrate phase equilibrium line (P-T) becomes steeper with the concentration increase of ethylene glycol, and the other is compressor factor of gas becomes smaller with the concentration increase of ethylene glycol.
Keywords: chemical energy source; hydrate; dissociation heat; ethylene glycol

Title: Numerical investigation and analysis of the heat transfer enhancement in oil-side of the panel-type radiator

Authors: GUO Xiaoxia, WANG Xiuchun
PP: 488-492
Abstract: The twisted tape inserts are simple vortex generators which can make fluid rotate. In this paper 3-D numerical simulations were presented for heat transfer enhancement in oil-side of one channel with the twisted tape inserts of the panel-type radiator.It is found that value of twisted-ratio which is the most important parameter of twisted-tape determines the strength of second-flow in the channel. As the value of twisted-ratio decreases, the effect of heat transfer enhancement is better and better.
Keywords: thermal engineering; heat transfer enhancement; panel-type radiator; twisted-tape

Title: Study on enhancement of regeneration of silica gel assisted by high-intensity ultrasound

Authors: YAO Ye
PP: 483-487
Abstract: This paper discusses the influence of hot-air temperature, acoustic power and frequency as well as the moisture ratio on the enhancement of regeneration (ER) of silica gel assisted by high-intensity ultrasound based on experimental study. The results show that the effect of ultrasound on the regeneration of silica gel is more significant under the lower hot-air temperature, the lower acoustic frequency or the higher moisture ratio in silica gel. This study is valuable to the application of the new regeneration technology in the dessicant air-conditioning system.
Keywords: intelligent power technology; ultrasound; regeneration; desiccant; silica gel

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