bluuebunny/crossref_metadata_2025 huggingface dataset:
A Consideration about Ecological Planning Method Based on Digital Technology
Authors: Wu Hao , Liu Ling Bo
Published: August 2013

In contrast to Chinas rapid urbanization, the development of urban & rural planning technologies remained relatively lagged behind; their guiding framework, urban & rural planning and design theories are also increasingly rendered invalid in addressing the ever-growing types of urban problems. Concepts such as eco-city have attracted wide attention in recent years due to their potential in solving urban problems. However, many of them remain at a theoretical stage and most ecological development index derived from these researches cannot be directly used in guiding urban & rural planning. This paper try to study the basic principles of ecological planning and the rules of the planning analysis models in an effort to establish an ecologically-oriented planning method.
An Impact Analysis of the Town and Country Planning Act towards the Master Planning of Chinese Small Cities: Case Study of Lianjiang Town
Authors: Liu Yun , Peng Chong
Published: August 2013

With the broadening and deepening of economic development, the urban growth of many small cities begins to present sprawl in China in the new century. Replacing the original act of urban planning, the Town and Country Planning Act became effective in 2008. This paper compares the contents of the two acts, and especially analyses the stipulations about urban land scale and spatial construction activities from the perspective of the revised legislation. Based on the introduction of the master plan of Lianjiang Town in Fujian Province, the paper holds that China can take advantage of the legal effect of the new act to make the master planning of small cities more cautious and rational, as well as to promote the popularity of smart growth concept in small cities.
Analysis of Population Density and Energy Consumption-Example from Yangtze River Delta in China
Authors: Zhang Lei , Zhang Da Yong
Published: August 2013

The purpose of this paper is to test the relationship between population density and energy consumption in China. To test the relationships above, Data was collected for sixteen cities in Yangtze River Delta from 1999 to 2009 in China. Econometric modeling of panel data analysis was used to examine the hypotheses. FE estimates and RE estimates were obtained. Hausman estimate have been used to select appropriate results. U shape between energy consumption and population density exists when controlling other variables. It means that cities have optimal population density for minimum energy consumption. The paper shows that population density have U shape influences on urban energy consumption.
The Research of Acute Toxicity Effect of Oil Spill to Zoobenthos
Authors: Zheng Li Na , Tian Ge , Wei Hai Feng , Liu Heng Ming
Published: August 2013

Iodometric determination of dissolved oxygen is used as experimental methods, through the determination of oxygen consumption of crude oil, gasoline , diesel , three different types of oil, oxygen consumption of Philippines clams and oxygen consumption of Philippines clams under the conditions of three oil pollution, variations of DO under the conditions of three oil pollution is researched. The results show that oxygen consumption of gasoline> oxygen consumption of diesel oil> oxygen consumption of crude oil. At the same time, oxygen consumption of gasoline changes with time by a big margin, diesel oil comes second, oxygen consumption of crude oil changed slightly with time.
Quantitative Analysis of Coupling Relationship between Regional Economy and Ecological Environment - A Case Study of Wanjiang City Belt
Authors: Huang Mu Yi , Wang Qi Ming , Liu Sen Bao , Pan Bao
Published: August 2013

Coordinated development of regional economy and ecological environment is one of the core issues of sustainable development practices. In this paper, the numerical parametric statistical method and geospatial analysis tools were used to analyze the spatial-temporal characteristics of coupling relationship between regional economy and ecological environment, the results show that:(1) The EKC of the regional economy and ecological environment is N-shaped, there exists co-integration relationship, but no granger causality between them. (2) The analysis of temporal characteristics shows that the index of economic curve increased relatively stable, since new century, it increases rapidly. The changes of the ecological environments index are relatively stable after it reaches a relative high level in 2005. (3) The spatial differences between regional economy and ecological environment show that all cities of Wanjiang City Belt have significant spatial variation characteristics. To be specific, the condition of regional economy and ecological environment in Hefei, Maanshan and Wuhu, etc. is better than Chizhou, Anqing and Xuancheng etc.
Reclamation of the Temporary Land use for the Road Construction
Authors: Luo Guo Zhan , Wang Jian , Liu Yu Peng
Published: August 2013

Land is limited and renewable resource, also the renewability of many composites of land productivity is limited. A large acreage of land is occupied temporarily or permanently by road construction projects. In the later stage of road construction projects, land reclamation is a key issue for land resource protection. Basing on investigation and study, this paper is to conclude the land reclamation methodology and key technologies, and provide technical reference.
Study on the Direction of Land Reclamation and Ecological Reconstruction in Jiaozuo Coal Mining Area under the Angle of Central Plains Economic Zone
Authors: Hu Chen Cheng , Chen Chao , Yu Yang , Zhou Xiang Bo , Lin Shan , Zhou Shu Jun
Published: August 2013

With the building of Central Plains Economic Zone written on the national development strategy, a new opportunity is approaching to the development of Jiaozuo. This paper firstly expounds the overview of Jiaozuo coal mining area and the connotation of Central China Economic Zone under the Angle of Central China Economic Zone, Combines the Research of Land Reclamation and Ecological Reconstruction with Related Practice in Jiaozuo coal mining area, it goes deeply into the analysis on the research according to the positioning and requirements of Jiaozuo in the Central China Economic Zone. Study on the direction of Land Reclamation and Ecological Reconstruction in Jiaozuo coal mining area under the Angle of Central China Economic Zone, aiming to provide some theoretical reference on the Research of Mine land remediation and utilization for Resource-exhausted Cities in the time of Development Strategic Transformation.
Study on Spectrophotometric Determination of Trace Copper after Flotation Separation Using Microcrystalline Adsorption System Loaded with CuI
Authors: Wen Xin Rong , Tu Chang Qing , Liang Qi Feng , Guo Hong Wei
Published: August 2013

The paper presents a novel method for the flotation separation of Cu2+ using microcrystalline adsorption system loaded with CuI prior to the determination by spectrophotometry. The effects of different parameters,such as the dosages of KI, ascorbic acid and octadecyl trimethyl ammonium bromide (OTMAB),various salts and acidity etc. on the flotation yield of Cu2+ have been investigated. The possible flotation separation mechanism of Cu2+ was discussed.The results showed that under the optimum conditions,octadecyl trimethyl ammonium bromide cation (OTMAB+) reacted with I- to produce the microcrystalline matter (Ms-M) of (OTMAB+·I-), Cu2+ could be reduced to Cu+ by ascorbic acid,and then Cu+ reacted with I- to form the precipitation of CuI.The precipitation of CuI was quantificationally adsorbed on the surface of Ms-M of (OTMAB+·I-) and was floated above water phase, the liquid-solid phases were formed with clear interface. In this condition, K+,Na+,Ca2+,Mg2+, Zn2+,Co2+,Al3+,Mn2+,Ni2+ and Fe2+ could not be floated.Therefore, Cu2+ was separated completely from the above metal ions.A new spectrophotometric method of determination of trace copper by flotation separation using microcrystalline adsorption system loaded with CuI was established.The proposed method has been successfully applied to the determination of Cu2+ in various environmental water samples, and the results agreed well with those obtained by AAS method.
Copigmentation of Mahonia Bealei Anthocyanins by Tannin
Authors: Jiang Yi Hua , Jiang Xin Long , Tang Shun
Published: August 2013

This study investigates the copigmentation effect and its underlying mechanism of tannin on Mahonia bealei anthocyanins (MBA). Results show that the addition of tannin increases the absorption and maximum absorption wavelength of MBA. At pH 3.73, the activation energy of MBA-tannin adduct is 2.43 times that of MBA. Under the same temperature, MBA-tannin complex shows better heat stability as exemplified by lower degradation rate and longer half-time. The light-induced degradation rate constant of MBA-tannin is 93.33% of that of MBA. It is shown in this paper that tannin can improve the heat and light stability of MBA and therefore is efficient as a copigment. Finally, the IR spectra suggest that the copigmentation effect is due to the formation of hydrogen bonds between tannin and MBA via associated hydroxyl groups.
The Research on the Effect of Br-Antibacterial Agents to Whitewater
Authors: Li Yong Hui , Niu Mei Hong , Li Na , Zhang Jian , Sun Yan Ning
Published: August 2013

This paper concerns with two brominated bacteriostatic agents, using the condition-test to research the inhibitory effect of the microorganisms in the waste paper pulp white water. Using the coated plate culture method of adding different amounts of antibacterial agents in Whitewater, the bacteria and mold in nutrient agar and potato medium experiments were used to observe the inhibitory effect. The results showed that the chosen brominated bacteriostatic agents (PS-2890, GB-3612) in this paper have a better antibacterial effect and 1#is better than 2#,the bacteriostatic agent can be chosen according to the actual situation of the plant .The bacteriostatic agent will achieve a higher rate of bacteriostasis when it is added to 5ppm, and this added amount can also meet the requirements of the factory on the prevention and treatment of microbial. The rate of bacteriostasis generally reached 40% -80% ,the highest 92.8%,when the antibacterial dosage is 3ppm-7ppm.
Dissolution and Photodegradation of Two Crude Oils in Seawater
Authors: Liu Hui , Sun Bing , Guan Le , Yan Zhi Yu
Published: August 2013

The fate of oil spilled on seawater is an important issue for marine environment. This paper studied the dissolution of two crude oils and the photodegradation of their water-soluble fraction (WSF). The relationship between the solubility and the component of the crude oils was studied by gas chromatograph, UV absorption and synchronous fluorescence spectrum, and the result indicated that the aromatic hydrocarbon was liable to dissolve in water and the dissolved organic matter (DOM) in seawater enhanced the dissolution of crude oils. Moreover, the photodegradation of WSF accorded with the pseudo-first order reaction, and the reaction rate constants for WSF 1 and 2 were 0.088 and 0.121 h-1, respectively. This investigation is helpful for better understanding the transformation of crude oil spilled on the sea.
CdS Quantum Dots Sensitized TiO2 Nanotubes Photocatalytic Degradation of Dimethyl Phthalate under Sunlight Irradiation
Authors: Bai Xiao Hua , Wang Shi Chang , Wang Chang Qing , Lei Xin You , Zuo Guo Fang , Pan Su Juan
Published: August 2013

The CdS quantum dots sensitized TiO2 nanotubes were prepared by sequential chemical bath deposition (S-CBD) method and characterized by FE-SEM and UV-vis spectroscopy. And they were used to degrade the dimethyl phthalate (DMP) in aqueous under sunlight irradiation. The results show that these photo-catalysts have the highest performance, while the initial concentration of dimethyl phthalate in aqueous solution is 10 mg / L, the degradation rates reaches above 80% in the optimum condition which is the CdS deposited 20 cycles, catalyst dosage ~3cm2, and the sunlight irradiating 180 minutes.
Antimicrobial Activity of Soy Protein Isolate-Essential Oil Monomers Edible Composite Films for Chilled Pork Preservation
Authors: Zhang Yun Bin , Wang Jing Wen , Jiang Juan , Li Yue Xia
Published: August 2013

Soy protein isolate (SPI)-essential oil monomers edible composite films were prepared by casting and solvent evaporation method. Films antibacterial activity and preservation effect on chilled pork were investigated. The results indicated that composite films showed significant inhibitory effect on the growth ofEscherichia coli,Staphylococcus aureus,Pseudomonasandyeast. And the antimicrobial activity of ﬁlms containing cinnamaldehyde was the highest. The films containing 6% essential oil monomers had better preservation effect on the meat samples compared with those without package or packed with single SPI edible films.
N, Fe Co-Doped TiO2 Photocatalyst Preparation by Sol-Gel Method with Visible Light Response
Authors: Yu Ping , Wang Shan Shan , Li Huan Huan , Li Wen Xiu
Published: August 2013

N, Fe co-doped TiO2 photocatalyst was synthesized by sol-gel method. The catalyst prepared was characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Ultraviolet and visible spectroscopy (UV-vis). The results showed that the N, Fe co-doped TiO2 prepared had the anatase structure. The absorption edge of the photocatalyst shifted to longer wavelength and photocatalytic activity for degradation of Methylene blue (MB) under Xe-lamp (350 W) was much more active than un-doped TiO2, N-TiO2 Fe-TiO2 and P-25.
Safety Risk Analysis of the Transmission Line Project Affected by Dangerous Slope Rock
Authors: Yang Tai Hua , Zheng Qing Hua , Wang Yang
Published: August 2013

The unstable slope rock is one of the geological disasters of mountains along the transmission lines, which includes the falling style and the slumping type, and the former is very dangerous, and threat to the security of transmission line. By means of a typical example study about the falling dangerous rock mass along the 10kV transmission lines, this paper analyzes qualitatively the basic characteristics, failure mechanism, influencing factors of the dangerous rock, et al., and calculated quantitatively the maximum depth affected by the impact of the dangerous rock to the transmission lines. The paper proposes the response measures of dangerous rocks risk, which is of a certain reference in other similar projects.
Colorimetric Screening Device for Pesticide Analysis Based on the Liposome
Authors: Guan Hua Nan
Published: August 2013

Monitoring of the organophosphorus pesticides dichlorvos at very low levels has been achieved with liposome-based nanobiosensors. The enzyme acetylcholinesterase was effectively stabilized within the internal nanoenvironment of the liposomes. Within the liposomes, the pH sensitive fluorescent indicator pyranine was also immobilized for the optical transduction of the enzymatic activity. Increasing amounts of pesticides lead to the decrease of the enzymatic activity for the hydrolysis of the acetylcholine and thus to a decrease in the fluorescent signal of the pH indicator. The decrease of the liposome biosensors signal is relative to the concentration of dichlorvos down to 10-12 M levels. Also a colorimetric screening device for pesticide analysis has been evaluated.
PCR-DGGE Analysis of Bacterial Diversity of Intestinal System in Hyperlipidemia Rats
Authors: Wu Ri Na , Pang Xiao Meng , Wang Xi Yan , Wu Jun Rui
Published: August 2013

Denaturing gradient gel electrophoresis (DGGE) analysis of 16S rRNA gene has been regarded as one of powerful tools for gaining insight into the bacterial diversity of intestinal system. In the present study, hyperlipidemia model was constructed in rat according to the tests of blood lipids. Fecal samples of rats were collected after 60d feeding, and DGGE was used to investigate the diversities of intestinal bacteria in the artificially-induced hyperlipidemia rats and normal rats. The results showed that two patterns had similarities, but there were also some different bacteria communities. Moreover, control group had much more bands than model group on gel, showing species in intestinal of model rats might be deduced by hyperlipidemia. It will be helpful to explore the relationship between hyperlipidemia and intestinal flora.
Study on Alfalfa Protein-Based Adhesive Modified by Sodium Hydroxide
Authors: Yu Wang Wang , Jin Yu , Liu Xue Jing , Wang Ming Yan , Li Cai Hong , Lei Wen , Jing Lu
Published: August 2013

In this study, alfalfa protein modified by sodium hydroxide was used to prepare adhesive. The effect on the bonding property by adding different amount of sodium hydroxide was discussed. The upper limit using temperature of alfalfa protein-based adhesive was increased and its bonding property was improved after the protein modified by sodium hydroxide. The adhesive prepared by alfalfa protein modified by 6% sodium hydroxide had the best bonding strength of 2.5MPa.
Design and Full-Scale Test for Steel Tubular Tower of UHV and EHV Quadruple-Circuit Transmission Line on the same Tower
Authors: Li Qing Hua , Yang Jing Bo , Han Jun Ke
Published: August 2013

State Grid Corporation of China has carried out research on key technology of UHV&EHV AC and DC multi-circuit transmission lines, the research on material and structure of transmission tower is the important part. The SSZT2 tower, on which 1000 kV AC double-circuit and 500 kV AC double-circuit are arranged, is the largest power transmission capacity all over the world. Q420 high-strength tubular steel, the plug-in boards and forging flanges are used in SSZT2 tower,and the forging flange with strength classification is applied for the first time. Through the monographic study on the tower structures, wind vibration coefficient, and biaxial bending of steel tube etc. The success of full-scale test verified the reliability in design and manufacture of multi-circuit steel tubular tower for UHV and EHV. Research results of this paper can be applied in UHV transmission line projects.
Computation of Radial Electromagnetic Forces on Power Transformer LV Windings due to Short-Circuit Currents
Authors: Zheng Han Bo , Han Jin Hua , Wang Wei , Li Xiao Gang , Li Yu Quan
Published: August 2013

The short-circuit electromagnetic force in radial direction induces critical mechanical stress on a power transformer. In this paper, the radial short-circuit forces which are exerted on transformer low voltage (LV) windings are investigated. Firstly, the mechanisms of leakage flux and short-circuit electromechanical forces in transformer coils are analyzed. Afterwards, based on IEC standards followed by short-circuit tests, calculations of radial short-circuit forces and evaluations of the ability to withstand short currents in LV windings are developed. The case studies and comparisons with improved measures show that the evaluation and calculation method is feasible and effective, and this method also offers three useful ways to strengthen the ability to withstand short-circuit currents for transformer windings.
Enhanced Geothermal Systems Projects and its Potential for Carbon Storage
Authors: Feng Chao Yin
Published: August 2013

Enhanced Geothermal Systems represent a series of technology, which use engineering methods to improve the performance of geothermal power plant. In some geothermal fields, the rocks are in high temperature but a low permeability, or the subsurface water is scarce. In these geological conditions, cool water was injected into the geothermal wells to fracture the tight rock and create man-made reservoir for thermal exploitation. Furthermore, these engineering methods can be utilized to improve the productivity of pre-existing hydrothermal power plants. To save water and treat the global warming, using carbon dioxide instead of water as working fluid was proposed. Numerical simulation reveals that the carbon dioxide has numerous advantages over water as working fluid in the heat mining process. The precipitation caused by carbon dioxide will restore part of carbon dioxide in the rock and reduce the micro-seismicity risk.
A Novel Power Limiter Based on Newton-Raphson Method for Doubly-Fed Induction Generator under Unbalanced Voltage Drop Conditions
Authors: Qiu Xiao Ming , Wang Ling Ling , Hu Shu Ju , Zhao Bin
Published: August 2013

A novel power limiter based on Newton-Raphson method is proposed in this paper for the Doubly-fed Induction Generator (DFIG) under the conditions of unbalanced grid voltage drop. Unlike the existing power limiters, which provide an approximate estimation of the maximal reactive power at the cost of introducing a large error in achieving its control target, ours formulates the design of power limiter into an optimization problem which tries to maximize the DFIG’s reactive power towards its two decisive factors: limited rotor current and rotor side converter’s output voltage. Finally the Newton-Raphson method is exploited to find the global maximum of the proposed optimization problem. Consequently, the proposed power limiter could more accurately determine the DFIG’s maximal reactive power without any loss of the accuracy in achieving its control target. Simulation results on a 1.5MW DFIG shows the efficacy of the proposed power limiter for DFIG under the conditions of unbalanced voltage drop.
Experimental Study of Linear Motor Direct-Driven Thermocompressor
Authors: Wu Xiao Hua , Yang Lu Wei , Yang Jun Ling , Lin Wen Ye
Published: August 2013

A prototype thermocompressor driven by linear motor was setup and experimental tudied. Peak-peak pressure in the system was influenced by the regenerator, the heating temperature and the gap clearance between piston and cylinder. The optimal frequency of the system was determined by spring constant and total mass of piston, shaft and moving iron. The peak-peak pressure was found to change little with filling pressure when the heating temperature was lower than 250°C, employing with N2 or He4 as the working substance. But when the heating temperature was higher than 250°C, peak-peak pressure increased with filling pressure. Besides, Helium4 was found to perform better than Nitrogen as the working substance. For heating temperature of 650°C and cooling temperature of 40°C, the peak-peak pressure could reach 0.412MPa with pressure ratio of 1.13 when the filling pressure was 2.2MPa, which could be used to drive the pulse tube crycooler (PTC).
A Method for In Situ Testing and Calibration of Moving-Coil Geophones
Authors: Zeng Ran , Zhao Yu Jiang , Lin Jun
Published: August 2013

A new method for measuring and identifying characteristic parameters of moving-coil geophones is proposed in this paper, where sine sweeping signal is considered as the electric excitation instead of the traditional vibrational excitation. A mathematical model of moving-coil geophone is constructed and the frequency response of 6-parameter is obtained in this paper. Using the expression as the objective function for fitting measured amplitude-frequency curve, geophones characteristic parameters are obtained. Finally, verification test is performed and the factors affecting measure accuracy are analyzed. The experimental results indicate that the presented method is suitable for production and maintenance, especially for in-situ calibration of geophones. This work provides a new way to design and manufacture portable geophone parameter testers.
Influence of a Deep NBL Structure on ESD/Latch-Up Immunities in the Power Device nLDMOS
Authors: Chen Shen Li , Wu Tzung Shian
Published: August 2013

In this paper, we propose a novel high-voltage (HV) nLDMOS transistor with a small Ron resistance, low trigger voltage (Vt1) and high holding voltage (Vh) characteristics. Here, we introduce a deep N+-buried-layer (NBL) into this HV nLDMOS to evaluate the ESD/latch-up (LU) parameters variation. These electric snapback parameters affect the reliability of proposed device and its performance. Eventually, we expect this proposed HV stucture processed better characteristic behaviors, which can be applied to the power electronics and ESD protection application of HV ICs.
Design and Application of Inverter Efficiency Test System Based on LabVIEW
Authors: Yao Wan Ye , Du Jin Ping
Published: August 2013

In order to enhance automaticity of inverter efficiency test, an inverter efficiency test system developed with LabVIEW software is designed. the test system can realize the communication between computer and programmable DC power supply via GPIB, and can complete parameter settings and output control of DC power supply. Eventually, output control of inverter is reachable. An experimental verification has been done, which shows that this system runs stably, and certain practicability is available.
Performance Improvement of SVPWM-Based Three-Phase Grid-Connected Inverters
Authors: Yao Zhi Lei , Xiao Lan , Xu Jing
Published: August 2013

An improved control strategy for three-phase grid-connected inverters with space vector pulse width modulation (SVPWM) is proposed. When the grid current contains harmonics, the d-and q-axes grid currents is interacted in the traditional control method, and the waveform quality of the grid current is poor. As the reference output voltage cannot directly reflect the change of the reference grid current with the traditional control strategy, the dynamic response of the grid-connected inverter is slow. In order to solve the aforementioned problems, the d-and q-axes grid currents in the decoupled components of the grid current controller are substituted by the d-and q-axes reference grid currents, respectively. The operating principles of the traditional and proposed control methods are illustrated. Experimental results show that the grid-connected inverter with the improved control strategy has high waveform quality of the grid current and fast dynamic response.
A Method of Distributed State Estimation in Dispatch Central Based on Ripe Data and Topology Model of Substation
Authors: Liu Jun , Su Da Wei , Qian Ke Jun , Shi Fei , Wang Li Wen
Published: August 2013

In this paper, a method of distributed state estimation in dispatch center based on ripe data and bus topology information of substation is proposed. Substation state estimation solves the reliability issues of basic data by means of processing the redundant information in substation side. By using a large amount of data source information of substation, state estimation can be performed efficiently in substation. On the basis of the unified data standard between master center and substation, uploading ripe data and calculation nodes topology structure are acquired in dispatch center level. Data rationality and consistency check of substation improve the state estimation accuracy of topology identification in dispatch master system. And also it provides reliable data for the online analysis software.
Improved Genetic Projection Pursuit Method Based on Measured Data on Power Quality Comprehensive Evaluation of the Application
Authors: Jia Xiu Fang , She Kai , Huang Shen Mao , Ma Jing Hua
Published: August 2013

This paper uses Multi-index to assess regional power quality comprehensively. This paper introduces genetic projection pursuit method on power quality comprehensive evaluation. Without human intervention, this method overcomes the traditional power quality comprehensive evaluation method is influenced by subjective factors. Based on this, we put forward improved genetic projection pursuit algorithm. In the process of projection pursuit model and in the field data, changing the maximum normalized to normalization of national standard limit. According to the field experiment data in QingHai province, we assess the results by analysis and comparison with the original method. The improved method is more accurate on power quality comprehensive assessment.
Fault Location Method in Complex Power Network Based on Power Quality Monitoring Data
Authors: Lan Jian , Wang Dong Xu , Zheng Xue , Liu Kai Pei , Yang Cai Xia
Published: August 2013

In this paper, a fault location method using power quality monitoring data is proposed. The fault location is divided into two classes including fault line recognition and fault distance calculation. Along the each power line in the target network some fictitious fault points are set and the fault voltage of each monitoring bus is calculated. The voltage dip calculation results and the fault line data are matched to form the learning samples and then train the designed fault line recognition BP artificial neural network. The trained neural network searches the fault line when actual fault occurs. After it finishes fault line searching the fault position is calculated using the function of voltage dip amplitude and fault position. The correctness and effectiveness of the proposed method is proved by the simulation results in standard IEEE-14 bus system.
Strategy for Breaker Failure by Communication Implementation
Authors: Ke Yi Kuan , Huang Pei Hwa
Published: August 2013

This main purpose of this paper is to study the implementation of the strategy for breaker failure under the condition of communication exchange in the power system. The method of breaker failure strategy in case of IEC61850 (Communication Networks and Systems in Substations) GOOSE (Generic Object Oriented Substation Event) aims to fast transmit signal to isolate faulty positions for maintaining safety security. The current strategy for breaker failure in substations is to use hardwire solutions to implement related applications for breaker failure. For integrating protective relays in substations, IEC61850 GOOSE schemes can customize a ring construct based on TCP/IP Ethernet to have flexible dispatch of smart grid solutions.
The Analysis of Influences of Source-Network-Load's Operation Mode on Power Grids Self-Organized Criticality
Authors: Cai Wan Tong , Liu Wen Ying , Zheng Wei , Liang Chen
Published: August 2013

The distribution of power flow is a determinant of power grids self-organized criticality, and the uniformity of power flows distribution can be quantified by power flow entropy. The theory of power flow entropy is applied in this article to the research of influencing factors of power grids self-organized criticality. First the mathematics mechanism of self-organized criticalitys quantifying by power flow entropy is researched. And then the influence of start-up mode (source), running state (network), load distribution (load) on power flow entropy is analyzed respectively. Finally, the Hexi grid located in Gansu province is employed to verify the critical influences of source-network-loads operation mode on power grids self-organized criticality.
Novel Bidding Decision Model for Generation Company Based on CVaR Model
Authors: Xie Pin Jie , Hou Jian Chao , Shi Quan Sheng
Published: August 2013

It is an urgent problem to solve for generation companies that how to find the optimal bidding strategy to obtain the highest profits and to decrease the risk to the lowest level. This paper presented a new bidding decision model with risk management for generation companies based on the conditional value at risk (CVaR). In the process of building the optimal bidding decision models, three situations are considered separately, including only consider maximize the expected return or the CVaR value of benefit, and considering the benefit and risk (CVaR). By this method, the generation companies can be determined the two decision variables of bidding price and bidding output to maximize its revenue at the same time to declare the risk.
Experimental and Numerical Study on Thermal Characteristics of High-Power LED Street Lamp
Authors: Ma Ai Chun , Wang Ya Hui , Ou Jian Ping , Zhou Cheng Jian
Published: August 2013

Based on the forward voltage measurement principle, a test device was designed for junction temperature measurement. The voltage temperature coefficient is-1.49mV/°C according to the experimental data, and a series of junction temperatures were obtained on various ambient temperature. A numerical model was built by using the CFD software Flent, which was verified with the experimental data. The influence of the different structure parameters of the heat sink on heat dissipation performance was studied numerically. The results show that the optimal structure parameters were as following: Fin number is within 8~12. Fin height is within 170mm~190mm. Fin length is within 35mm~55mm. Fin thickness is within 1mm~3mm. Bases radius is within 33mm~40mm. With the chip junction temperature and the radiator weight as optimizing object, the optimal parameters were obtained as following: Fin number is 12. Fin height is 190mm. Fin length is 55mm. Fin thickness is 1.5mm. Bases radius is 33 mm.
Fuel Common Rail Injection System of RT-Flex Marine Intelligent Diesel Engine and its Simulation Dynamic Model
Authors: Wang Yong Jian , Chen Jing Feng , Li Si Qin
Published: August 2013

Based on comprehensively analyzing the whole structure and its working performance of RT-Flex marine intelligence diesel engine and entirely mastering this kind of engine fuel common rail injection system’s composition, working principle, taking 7RT-Flex60C as simulation object, the mathematical models of this system’s composing part are designed, by using Matlab/Simulink simulation tool, fuel common rail injection system simulation model is set up, then comparing with the simulation data with rack test data, the accuracy and effectiveness of the model are test and verified. The built up model provides a convenient and practical method for design, optimizing and simulation of fuel common rail injection system.
The Influence of Intake Temperature and Excessive Air Coefficient on the Performance of a Gasoline HCCI Engine
Authors: Zhou Jing Lei , Shen Ye Chun , Zhang Chun Hua , Pan Jiang Ru
Published: August 2013

Mean indicated pressure and indicated thermal efficiency of practical cycle are essential criteria to evaluate the performance and fuel economy of the engine. The HCCI tests fueled with gasoline are conducted on a modified engine. With the change of intake temperature and excessive air coefficient, mean indicated pressure and indicated thermal efficiency are measured. The results show that with the increase of intake temperature, mean indicated pressure and thermal efficiency tend to increase, and with the increase of excessive air coefficient mean indicated pressure increases while the rising rate of indicated thermal efficiency decreases.
Design Calculation and Test of Lubricating System for Model 190 Diesel Engine
Authors: Yang An Jie , Ma Jian Hui
Published: August 2013

The new design lubricating system of model 190 diesel engine were calculated and tested. Amount of oil which delivered by the rotor oil pump is 6.12 liters, oil pressure from oil pump is greater than 200kPa, it can fully meet the requirements of cooling cycle. The oil sump is designed to meet storage capacity requirements and the residence time requirements. The finalize test results of the diesel engine show that the lubricating system matched with the engine works well, the indicators of the power, economy, reliability achieve the design and the standard requirements.
Mechanical Model of Pelletization in the Impressing Roller System
Authors: Huang Xiao Peng , Wan Fang Xin , Wu Jing Feng
Published: August 2013

By the force analysis of alfalfa grass powder material layer in work area of circular mould pelletizing system, grass pellet briquetting mechanism when alfalfa grass powder pass work area was explained, function relationship between the thickness of material layer and the circular mould angle was established, force balance equation of material layer differentiation unit under the general conditions was deduced, and the total force of material layer applied by circular mould was obtained. Research result has practical meaning for guiding the process test of grass pellet product and optimizing product structure, and has a certain theoretical reference value for in-depth revealing granulating forming mechanism of hoop standard granulator.
Comparison of Finite Difference and Finite Volume Method for Numerical Simulation of the Incompressible Viscous Driven Cavity Flow
Authors: Wang Jian , Li Jiang Fei , Cheng Wen Xue , Yuan Lian , Li Bo , Fu Zhi Zhong , Jin Long
Published: August 2013

In this paper, finite difference method and finite volume method are applied to incompressible viscous driven cavity flow problems, and their results are analyzed and compared. As for the finite difference method, second-order upwind and second-order central difference format are applied to the discretization of the convection and diffusion items respectively. For the finite volume method, three different ways are utilized to discretize the control equations: QUICK, second-order central difference and third-order upwind formats. The results show that computing time as well as calculation accuracy exponentially depends on Reynolds number, discrete formats and grid numbers.
Numerical Simulation of Transient Flow in Products Pipeline
Authors: Wang Zhen Ye , Li Jiang Fei , Yuan Lian , Fu Zhi Zhong , Li Bo , Cheng Wen Xue , Jin Long , Liu Lei
Published: August 2013

In this paper, explicit difference scheme, implicit difference scheme and characteristics method are separately used to simulate the transient flow in products pipeline. The simulation result can be used to prevent water hammer in the pipeline of unsteady situation and to improve the efficiency and safety in oil transmission systems. And then, the stability and accuracy of the three methods are compared by adopting different time steps. For explicit difference method, large fluctuation may occur in case of large time step. For implicit method, the result is weakly affected by time step, only if the relaxation factor selected is reasonable. For characteristics method, the results have a high convergence speed and precision. The results show that, in the situation of valve shut down in terminal, it takes about 1.1×104 seconds to return to a new steady state.
Research on Calculation Method of Engine Cooling Fan
Authors: Shen Kai , Chen Hong , Gu Shi Fan , Ni Ji Min
Published: August 2013

It’s introduced the method of calculation, modeling techniques and solution techniques of the aerodynamic performance of engine cooling fan. Based on a fan-tunnel test, the relation between static pressure, power, efficiency with volume flow is calculated in Fluent. It is proposed a few improved models and compared the calculations of different models. It’s analyzed the problems and reasons in the calculations of models and proposed the improved methods in fan test and numerical calculation. Keywords:Cooling Fan, Aerodynamic Performance, Models
The Design and Economic Analysis of Ice Cold-Storage Air Conditioning Unit on a Municipal Project in Seoul
Authors: Yang Juan Juan , Zhang Li , Wang Xiao Liang
Published: August 2013

The Paper presented the structure and operation mode of ice cold-storage air conditioning unit, compared its operation cost with common chiller. At last, through the economic analysis, the paper indicated that the ice cold-storage unit has great promotion potential and prospect for development.
Solar Energy, Methane, China Kang Integrated System Design
Authors: Ren Hong Guo
Published: August 2013

In order to reduce energy consumption, solve the rural house of low energy consumption, integrated system is imperative under the situation of the new technology is applied to the villages and towns in energy conservation and emission reduction can therefore play a big role. This paper puts forward in the northeast area the heated kang facilities, the solar energy and methane integration, this paper introduces the integrated system design part, draw the system design, and the system's working principle and features a detailed explanation.
Numerical Simulation on Axial Flow Fan Performance with Changing Tip Clearance
Authors: Ye Zhou , Zhao Hai Yang , Zhang Lu , Li Chun , Gao Wei
Published: August 2013

Taking the relative tip clearance as the variable, we numerically simulated the effect of tip clearance size on the performance of a straight-blade axial flow fan using the 3-D viscous flow solver. The tip clearance is referenced in the relative value. By comparing the flow field corresponding to five different values of the tip clearance 0, 0.5%, 1.0%, 1.5% and 2.0% with other parameters kept constant, we concluded that the changing of the tip clearance has a great influence on the performance of the axial flow fan. Both the efficiency and the total pressure decrease with the increase of the tip clearance.
Research on AC/DC Power Flow Algorithm Considering Control Transformation of HVDC System
Authors: Ye Peng , Gu Hai Fei , Dang Wei
Published: August 2013

In this paper, a new approach to AC/DC power flow is proposed on the basis of uniform methods and control logic conversion of operation state. This method can take the action of the converter transformer tap into consideration and effectively deal with the conversion of HVDC system operation modes in power flow calculation. According to judgment logic of different operation modes, independent subroutines which are programmed in advance are employed to complete the AC/DC power flow calculation. The programming and simulation results demonstrate the approach is clear and easy to program and the transformer tap adjustment and the transformation of operation mode in HVDC system can be solved effectively in power flow calculation.
Investigation on the Dynamic Characteristics of PMFCLs for Large Capacity Applications
Authors: Zou Liang , Xu Jia Xiang , Yu Qing , Liu Tao , Yang Xiao Shuai
Published: August 2013

Permanent-Magnet-Biased Saturation Based Fault Current Limiter (PMFCL) is a preferable solution to suppress the fault current, and may find early applications in large capacity power systems due to prominent advantages. Firstly, the topologies and the operating principles of the PMFCLs are elucidated in this paper. Then a new concept namely effective magnetic flux density is proposed in order to describe the overall impacts of the magnetic field on the current limiting capacity of the PMFCLs. Lastly, theoretical analysis and mathematical simulation on the dynamic characteristics of different modes of PMFCLs are carried out comparatively. All the results present invaluable fundamentals for further study on the operating mechanism of different modes of PMFCLs as well as optimization of the fault current limiting topology design.
Air-Fuel Ratio Fuzzy PID Control for Coal-Bed Gas Engine Based on Fuzzy PID Feedforward
Authors: Shao Jin Ju , Gao Song , Tan De Rong , Fang Hai Tao
Published: August 2013

In order to eliminate the adverse effects of coal-bed gas concentration disturbance to coal-bed gas engine air-fuel ratio control and the large pure time-delay existed in signal response of methane transducer, a fuzzy PID feedforward flow control plan was proposed for gas supply system. Fast and efficient flow control was performed in advance according to air-fuel ratio control requirements to eliminate air-fuel ratio control delays caused by the coal bed methane concentration disturbance. Based on the mentioned feedforward flow control plan, considering the premix coal-bed gas engine air-fuel ratio fluctuations arising from engine speed disturbances, a fuzzy PID closed-loop control scheme was proposed. By analyzing different air-fuel ratio control characteristics in transient condition and steady condition, the different closed-loop control of the air-fuel ratio was used to suppress air-fuel ratio fluctuations caused by engine condition changes. Compared to traditional PID control, the simulation results show that the air-fuel ratio fuzzy PID closed control scheme based on fuzzy PID feedforward flow control has ideal control effect, preferable stability and robustness. The air-fuel ratio control delays caused by the coal-bed methane concentration disturbance is well solved, and the problem of air-fuel ratio disturbance is well solved when the engines working condition changes, meeting the pre-mixed coal-bed gas engine air-fuel ratio control requirements.
Impact Analysis of Effective Inertia Competition on Power System Inter-Area Damping Characteristics
Authors: Liu Cong , Liu Wen Ying , Zheng Wei , Liang Chen
Published: August 2013

In allusion to the discrepancies of the equivalent generator's equivalent inertia based on mechanical inertia time constant and that of the power system under practical operations, the concept of effective inertia is proposed. By analyzing a two-generator system, the main factors influencing the dominant mode damping ratio of inter-area oscillation, besides the supplementary damping control, are analyzed as the three: effective inertia, load level and network structure. When the former two are constant, the crucial factor for dynamic stability reducing in terms of operation mode change can be ascribed to the effective inertia competition. Practical calculation of Gansu power grid simulation is conducted and the result of argument is verified.
Novel Scheme of Fast Protection and Control for Feeder Automation
Authors: Zou Gui Bin , Gao Hou Lei
Published: August 2013

This paper proposed a fast protection and control scheme of feeder automation (FA) for the modern distribution grid. The smart terminal unit (STU) is installed at each switchgear of the feeder, and STU has a directional over-current component. The adjacent STUs are connected each other by the optic fibre network, and ultimately they are all connected to the central station of FA. STU detects the local current and the status of breaker in real time, meanwhile exchanges the information with adjacent STUs. Through analyzing the information, STU can make a correct identification for a faulted section. Therefore, the faulted section can be isolated and power supply of non-faulted section can also be restored rapidly. Case analysis illustrates that the proposed fast protection and control scheme is valid and feasible.
Study on the Power Transformers Deterioration State Evaluation Index System
Authors: Xie Qing , Hou Shan Shan , Liao Feng , Hu Wei Tao
Published: August 2013

Large power transformers as the the hub of power system equipment, its operation reliability directly related to the security and stability of the power system. When we have to make a more comprehensive and accurate judgment for running health status of the power transformer,we must get the characteristics of the transformer state. In this paper, we can pick out representative indicators from the existing power transformers deterioration state elements. Thereby, we can study more systematic and targeted the deteriorated state of the power transformer. Keywords: power transformers; deterioration state ;evaluation
Energy Storage Based Adaptive Control of Disturbed Load Interconnected Power Systems
Authors: Zhou Guo Peng , Cheng Shi Jie , Huang Jin Hua , Liu Di
Published: August 2013

A simple interconnected power system with periodic load disturbance is considered, an energy storage based adaptive controller is proposed to output tracking and disturbance completely rejection for the system. Since the periodic load disturbance is uncertain with both amplitude and frequency, by constructing a new exosystem, the output tracking and disturbance rejection problem is solved with output regulation theory. By designing an internal model for the complicated system and introducing an appropriate transformation, the output regulation problem is changed into the stabilization problem of a new augmented system. With the help of adaptive control technique, the designed dynamic energy storage controller can solve stabilization problem of the augmented systems as well as the output tracking and disturbance rejection problem for the original system. Finally, the simulation results show the effectiveness of the proposed control strategy.