bluuebunny/crossref_metadata_2025 huggingface dataset:
A Simple and Accurate Modeling Method for Photovoltaic Cells Using Explicit Equations
Authors: Kong Xiang Yu , Xu Yong Hai , Zeng Ya Wen , Tao Shun , Xiao Xiang Ning
Published: August 2013

A numerical method for determining the five-parameter model of photovoltaic cells is presented in the paper. Explicit equations are applied to analyze the relations between parameters and determine their values by optimization algorithm. Unlike previous works, the application of explicit equations and the simple algorithm make the proposed method very simple. The proposed method is validated by Shell S65 .It is found that the proposed method gives superior results not only on standard but also on operating conditions of photovoltaic cells. Considering its simplicity and accuracy the method can be applied in practice widely.
The Architecture Research of the Building External Shading and Building Energy-Saving System Based on the Intelligent Control
Authors: Hu Zhi Gang , Guo Peng Wei , Wang Xiao Li
Published: August 2013

In this paper, we present a solution without power consumption based on intelligently controlled action of the building external shading facilities, which is provided power supply by the third generation flexible solar cells. The signal, which is measured by wind, light, rain and temperaturesensors, is processed by the Microcontroller Unit system (MCU) controlling the motors of building external shading facilities, and then movement of the building external shading facilities is regulated to achieve the most comfortable of the indoor environment.
The Influence of Fly Ash on the Crack Performance of Airport Pavement Concrete by Dumbbell Test Method
Authors: Liu Yan
Published: August 2013

In this paper, the influence of fly ash with different dosage and grades on the crack performance of airport pavement concrete was studied. Its exercise new Dumbbell Test Method could make the airport pavement concrete material be tested accurately and quickly during early-age from pouring. The effect of fly ash with different grades and dosage on volume stability of airport pavement concrete was evaluated by Dumbbell Test Method. Also the paper analyzes the mechanism of the influence of fly ash on the crack performance of airport pavement concrete.
The Research on the DEM Simulation of the Railway Ballast Tamping Process
Authors: Wang Xue Jun , Hua Bin , Hu Bin , Chi Yi Lin , Ding Yan Fang
Published: August 2013

Ballast degradation and unrecoverable deformation are emerged on the railway ballast track under the loads of high-speed and heavy loading locomotive. With the change of tamping frequency, a better understanding of the physics of compactness degree is important for long-time stability of ballast. This paper presented a numerical investigation of the bulk materials dynamics and the transient impaction of a system of irregular polyhedral particles confined with a rectangular box with a retaining wall subjected to cyclic tamping loading. Sphere packing method was being used in this study to simulate typical full-sized ballast particles. This paper aimed to establish firm-soft coupling particle-flow tamping operation simulation numerical model based on contact dynamics theory. This study checked the validity of the model while different tamping working conditions and out-loads was being implemented. The study shows that discrete element method (DEM) is an efficient method to reveal the rearrangement rule of railway ballast after the process of tamping operation.
The Study on Design Method of the Sustainable Dwellings in Mountain Areas Based on BIM
Authors: Zhuang Zhi , Wang Shi Xu , Zeng Xu Dong
Published: August 2013

This paper shows the difficulties of the dwellings’ sustainable development in mountain areas on the basis of the fast pace of urbanization and the development of the dwellings in China, in terms of environmental resources, spatial form, regional culture and construction technologies. Then this paper analyzes the application possibilities of BIM on the sustainable dwellings in mountain areas through the discussion of the correlation between BIM and Sustainable Architecture, and proposes the research ideas of design methods.
Experimental Study on Seismic Performance of CFRP Strengthened RC Frames Damaged by Earthquake
Authors: Gao Qiu Mei , Wang Lai , Zhang Ying
Published: August 2013

In this paper, we carried out low cyclic loading test over CFRP strengthened seismic-damaged RC frame named KJ-2 with the quasi-static test method, and compared the seismic performance with the same sections and materials RC frame named KJ-1 which was unstrengthened. We study the seismic performance such as hysteresis curve, skeleton curve, stiffness degradation, bearing capacity degeneration, displacement ductility, and energy dissipation capacity of the reinforced RC frame. On this basis, we analyzed the results of this test in order to obtain some guiding opinions for asymmetric span RC frames that strengthened by CFRP, and provide main preference basis or future national or industry standards.
Research Progress of Solar Pond Technology
Authors: Gao Chun Juan , Zhang Qi , Wu Hai Hong , Huang Xi Ping
Published: August 2013

The discovery and heat-collecting principle of solar pond was introduced. Meanwhile, the research development of solar pond technology in experimental study and theoretical study were summarized. The development of solar pond technology in applied study also was described. Finally, the developing tendency of the solar pond technology was prospected.
Study on the Output Power of the PV Power Plant Model Based on ANFIS
Authors: Liang Hai Feng , Wang Hai Hong , Liu Zi Xing
Published: August 2013

in order to study the output power of PV plant in depth, effective and reasonable methods of modeling for PV power plant are explored and adaptive neuro-fuzzy inference system (ANFIS) based on Takagi-Sugeno (TS) model is proposed in this paper. According to the power output characteristics of PV system and a variety of factors which impact, three kinds of model of PV plant power output are established based on subtractive clustering ANFIS. After model test and calculation for confidence interval estimate of power output, the results show that the accuracy of the model is able to meet the practical engineering application requirements and the second model is optimal by comparison. In conclusion, ANFIS provides an innovative and feasible model establishment method for the power output of PV plant.
The Research and Design of Automatic Tracking System of the Light Based on the LOGO Controller
Authors: Tang Zhan Jun , Yang Pei Zhi , Zhang Tong
Published: August 2013

Use of automation technology sun tracking is to improve the photovoltaic efficiency of the important ways, according to research the power generating efficiency is increased by 30% to 40%, the existing solar power station solar light tracking for the software control, namely, according to historical data, based on the analysis and calculation of the solar motion law, writing software control, real-time monitoring, cumulative error manual correction, regularly. In order to solve the above problem, this paper describes the design of a novel solar tracking system, sensor, controller, actuator to carefully design and selection, based on the realization of the LOGO! Intelligent controller as the core of hardware platform, the development of the control software, and the system is simulated and validated, finally through the joint hardware and software debugging and practical operation, the system run stable and reliable work, and can switch reset and the weather conditions to realize the automatic open Ing and closing of the automatic tracking system of control function
Analysis on Biomass Resources and Potential of Developing Biomass Energy in Yunnan Province
Authors: Zhang Xia , Cai Zong Shou , Chen Li Hong , Chen Ying
Published: August 2013

As one of a agricultural provinces of China, Yunnan has abundant biomass resources such as crops straw, wood wastes and so on. However, the exact annual output of biomass resources has not been statistically calculated. Through carefully collecting and recalculating data from 2000 to 2008 year, the accurate main crops straw yield of Yunnan were calculated by using the Straw to Product Ratio (RPR) coefficient of different crops in this paper. Yunnan produced some 23 million tons of crops straw per year. The three largest contributions to the total output of crops straw were from corn, sugarcane and rice, which amounted to 39%, 28% and 16% of the total crops straw respectively. This paper analyzed the present status of utilization of biomass in Yunnan and proposed that more than 60% of crops straw were burnt in the field at present, which has caused serious environmental pollution. There was still 19 million tons of biomass from agriculture, forestry and flower industry each year can be used as biomass energy resources, which was equivalent to about 9.5 million tons of standard coal, and can provide about 2.76 × 1014KJ biomass energy.
Application of Prediction Algorithm of Photovoltaic Power in Distributed Photovoltaic Volatility Control
Authors: Xiao Hong Xia , Chen Hong , Mo Hua
Published: August 2013

For the uncertain characteristics of output power of distributed Photovoltaic (PV), the energy storage device is used to make up the error, between the predicted output and the actual output, to achieve the volatility control of PV power system. This paper presents that the application of support vector machine (SVM) in the power output forecasting of PV volatility control. Based on the complex and non-linear of the factor affecting the PV output, it points the non-linear relationship between the influencing factors and predicted values, and it establishes the SVM regression model of the PV system. Meanwhile, combined with the historical data of the PV operation, it gives the predictive values. Both theoretical analyses and calculation examples show that this method is simple, with high precision, and it is more suitable to the PV output volatility control.
Comparison of Methods of Wood Chip Moisture Evaluation
Authors: Rimár Miroslav , Kuna Štefan
Published: August 2013

The article deals with the evaluation of wood chips moisture and compares two methods of moisture determining. The problem of moisture determining consists mainly in selecting a suitable method according to the estimation of content of water in wood chips. Another factor to be considered is the fact that moisture in wood chips due to the ambient conditions (temperature, pressure, humidity) changes over time.
Electric Heating Biogas Digester Experimental Research and Numerical Simulation of Fluent
Authors: Jia Ling , Xing Shi Lu , Tian Rui , Wang Li Ying , Li Song
Published: August 2013

In order to verify the correspondence of numerical simulation and experimental results in the electric heating biogas digester system, an electric heating biogas digester experimentdevice was established, and according to the experimental conditions, software Fluent was used to simulate the process of the heat transfer in the system. Before simulation, analyze theexperimental data through the calculation of heat balance and modify it, then use the modifiedexperimental data, compile UDF to characterize the dynamic boundary conditions, choosestandard turbulence model through the Raleigh number, numerical solving the process. Numericalsimulation results show: simulation process basically reflects the experiment, the simulation dataand experimental data are good agreement, and error within 1%. It is concluded that thenumerical simulation analysis is accurate, method is reliable.
Experiment Research and Mechanism Analysis on the Thermal Properties of Solar Anaerobic Digester
Authors: Wang Li Ying , Lin Li Hua , Gao Hong , Jia Ling , Tian Rui
Published: August 2013

According to the resource characteristics of Chinas western alpine region, the thermal equilibrium experiment and analysis of solar digester is studied in this paper. Under the simulation conditions, the experiment showed that preheating time of solar digester will be shorter with the heat temperature increasing, and the shortest preheating time is 35 min. At the same time the calculation result showed the effective thermal efficiency in preheating stage is gradually increased from 75.7%, 84.6% to 99.3%. In order to maintain the digester thermostat 860 kJ/m3/h heat should be provided to the digester. The digester temperature can be maintained above 33°C within 10 hours in the case of a low humidity in summer. The auxiliary heat sources and additional insulation layer added to the system should be considered in the case of winter and high humidity day in summer.
Improving Calorific Value and Reducing Corrosiveness of Biological Oils
Authors: Xu Ying Mei , Wang Wei , Liu Qian , Song Zhao Xia , Sun Li , Zhao Ming Ju , Zhang Qiu Min
Published: August 2013

In order to improve the calorific value of biological oils and reduce its corrosiveness, magnesium oxide and calcium oxide are added as reactants and carboxylic acid used to induce separation. This paper investigates the effects of using different magnesium oxide/calcium oxide molar ratios on the calorific value of bio-oil. Analysis of the results show that adding magnesia alone improves the quality of the water phase and the calorific value of the bio-oil. A MgO/CaO mole ratio of 9:1 improves the pH of the bio-oil from 2.5 to 6.5 and achieves a phase separation of m (oil phase) / m (water phase) = 75:25, as well as increasing the heating value of the oil by 19.29% from 16.819 MJ/kg to 20.063 MJ/kg. Note that MgO/CaO mole ratios with calcium oxide ratios greater than 9:1, only slightly increase the heating value of bio-oil overt the raw non-separated oil.
Application of Solar Energy and Gas Compound Hot Water Supply Technique
Authors: Huang Pu Jie
Published: August 2013

With energy saving and comfort as top priorities, a hot water supply system is designed with solar energy and gas as compound heat sources. In the design, mathematical models are set up for the solar energy and gas compound hot water system and for its economic evaluation. Taking a three-bedroom flat building in Guangzhou City for example, a whole years energy consumption for domestic hot water is simulated; the gas consumption is calculated; comparisons are made between the new system and the gas hot water supply system in terms of their technique, economy and energy efficiency. Results show that the solar energy and gas compound hot water supply system effectively saves energy and has good economic benefits.
Optimizing the Formula for Rice Husk Pellet Fuel Using Orthogonal Array Testing
Authors: Xu Su , Tao Yong Gui , Liao Wen Chao , Yan Bin
Published: August 2013

Orthogonal array testing was adopted to optimize the formula for the molding of rice husk pellet fuel. An L9(34) array was used; moisture content and ratio proportion of the two additives were set as main influencing factors; the calorific value crush resistance, ash content, density and appearance of rice husk pellets were used as indicators. Visual analysis showed that the optimal formula for the molding of rice husk pellets was: 72% husk, with 15% water, 5% glycerol palmitate and 8% anthracite added. Further tests showed that with these ratios, the calorific value of the obtained pellet fuel17.5MJ/kg, crush resistance98%, density650kg/m3, which meets the standard of European biomass pellet fuel industry.
Research on Optimization Model of China's Bio-Fuel Ethanol Subsidy
Authors: Cao Li , Lei Sui Jiang
Published: August 2013

As a renewable energy, the development of bio-fuel ethanol has caught the attention of the whole world. Consensus has been reached that subsidy policy should be formulated to promote the industrial development. Subsidy policy, however, is faced with such problems as lack of scientificity and low efficiency, making it important to design the mechanism of scientific subsidy policy. To provide scientific basis for the government in this respect, this paper will deal with the establishment of random optimization theory model of multi-objective bio-fuel subsidy in connection with energy gap, food safety as well as survival and development of non-food bio-fuel ethanol enterprises.
Study on Biomass Carbonization for Bio-Char Production
Authors: Xiong Shao Wu , Zhang Shou Yu , Guo Xi , Dong Ai Xia , Chen Chuan , Wu Qiao Mei , Wang Jian
Published: August 2013

Bio-char with high fixed carbon yield is a potential material for barbecue and hot pot fuel. In the study, the effects of the process conditions including raw materials, carbonization temperature and residence time on the combustion characteristic of the resulted bio-char were investigated. Here, bio-char yield and combustion characteristic were used as evaluation indexes. It is foud out that the bio-char prepared from cotton stalk under the conditions of the final temperature of 500 oC and the residence time of one hour shows the best combustion characteristics.
Study on Drying Characteristics of Microalgae under Different Conditions
Authors: Chen Chun Xiang , Ma Xiao Qian , Li Xiao Cong , Qin Wei Ping
Published: August 2013

To find out an alternative of coal saving, a kind of microalgae, Chlorella vulgaris (C. vulgaris) which is widespread in fresh water was studied by digital blast drying system. The effect of the moisture content, drying thickness and temperature on the drying process of C. vulgaris were investigated. The results indicated that when the drying temperature is high, the moisture content is low and the material thickness is small, the drying time is short. The drying process of C.vulgaris can be divided into two stages, and the mass loss is mainly occurred in the second stage . The results will provide guidance for design of drying process and dryer of microalgae.
A Power Prediction Method for Photovoltaic Power Station Based on Neutral Network Using Numerical Weather Information
Authors: Zhu Hong Lu , Yao Jian Xi
Published: August 2013

As the installed capacity of photovoltaic power station is growing, the power prediction techonology is of great important to reduce the random damage to the power system. A prediction model using neural network is proposed in the paper, the solar radiation model is adopt to ensure the accuracy of the prediction results in clear sky contions.Through the analysis of photovoltaic power station output power influence factors, the the solar radiation intensity, humidity and temperature are chosen as the input of the neural network prediction model.At the same time, in order to improve accuracy the photovoltaic power station power prediction model, the power adopt numerical weather forecast information. And the prediction model is tested by the photovoltaic power station historical operation data, and the short-term power prediction has a good performance.
Study on Mechanism of Low Temperature Co-Pyrolysis of Duckweed and Flame Coal
Authors: He Xuan Ming , Fang Jia Qi , Pan Ye , Li Wei , Wang Xiao Juan
Published: August 2013

Co-pyrolysis characteristics of long flame coal mixed with duckweed in different proportions were studied by using TG. And the kinetic parameters was also figured out by using the method of Coats-Redfern. It was exhibited significant synergistic effect created more the light component between duckweed and coal during co-pyrolysis, The pyrolysis rate of flame coal is much smaller than biomass, and the starting pyrolysis temperature of flame coal is higher than biomass. The kinetic analysis indicated that the pyrolytic processes can be described as first order reactions model. The average activation energy of duckweed and coal was 39.14kJ/mol and 46.43kJ/mol , and with the increasing of the duckweed proportion, pyrolysis activation energy was decreased.
Study on the Conditions of Straw Powder Degradation to Produce Reducing Sugar in Mixed Cultivation
Authors: Liu Yi , Yuan Yue Hua
Published: August 2013

A strain of trichoderma and aspergillus filtered out from the environment was used to ferment in powder-liquid medium where the main carbon source was rice straw powder. Along with the fermentation, the pretreated rice straw powder was catalytic degraded into reducing sugar by enzyme. There was orthogonal test based on single factor experiment. The orthogonal experiment showed that the crude enzyme liquid dosage caused the biggest influence on the degradation of straw powder, second was temperature and followed by pH value, and the straw powder concentration caused the minimum effects on degradation. The optimal conditions of degradation of rice straw powder was: the percentage of the volume of crude enzyme liquid in total degradation liquid was 3%, initial straw powder concentration was 60g/L, the pH value was 4.8, and the degradation temperature was 50°C. Under the optimal conditions, the degradation rate could be able to reach 80%.
Application of Solar Energy Integration Technology in Metallurgy
Authors: Liu Qian Shu , Wu En Hui , Hou Jing , Li Jun , Huang Ping
Published: August 2013

Solar energy has the resource characteristics of cleanlinessno pollutiondispersion and intermittence. The research results and progress of solar energy integration technology application in the photothermal iron-making, photothermal concentrate titanium white waste acid, photovoltaic steel-making and preparation of pure iron by photovoltaic electricity both at home and abroad are summarized. As an effective clean energy, solar energy is regarded having a great application prospect in the metallurgical field.
Biohydrogen Production by Co-Fermentation of Starch Wastewater and Sludge under Thermophilic Condition
Authors: Zheng He Shan , Guo Wan Qian , Yang Shan Shan , Feng Xiao Chi , Zhou Xian Jiao , Liu Bo , Ren Nan Qi
Published: August 2013

In this paper, the possibility and potential of biohydrogen production by co-fermentation of starch wastewater (SW) and WAS under thermophilic temperature was studied in batch fermentation tests. WAS was first pretreated by thermophilic enzyme together with low intensity ultrasound (LIU) to improve the biochemical degradability. Then After 8 h pretreatment, all soluble substances were much higher than raw sludge without pretreatment. In addition, the SCOD, carbohydrate and protein of the tests which were accelerated by low-frequency ultrasound were 11.5% 18.4%, 17.8% higher than the control, respectively. Results from the co-fermentation further demonstrated that the sludge had high pH buffering capacity. A mixing ratio of 1:1 was found to be the best among of all co-fermentation tests. Moreover it was proved in this study that hydrogen production by co-fermentation of starch wastewater and sludge was a promising technology to recovery energy from the waste.
Conversion of Glucose into 5-Hydroxymethylfurfural with WO3 - MoO3 Mixed Metal Oxides
Authors: Du Chang Hai , Zhang Zhi Wen
Published: August 2013

5-hydroxymethylfurfural (HMF) was produced from glucose using WO3-MoO3 mixed metal oxides as the catalyst in a biphasic system (H2O-NaCl/THF), comprised of reactive aqueous phase saturated with NaCl, and containing AlCl3.6H2O, combined with an organic extracting phase consisting of tetrahydrofuran (THF). The influences of different catalysts, initial concentrations of glucose and reaction time on preparation of HMF were investigated. As a result, A HMF yield of 61% could be obtained at 170 °C in 40 min. Recycle of the aqueous phase and WO3-MoO3 demonstrated constant activity after 4 cycles of use.
Effect of Acetic Acid on Ethanol Fermentation by Engineered Escherichia coli SZ470
Authors: Wang Jin Hua , Huang Feng , Zhao Xiao , Zhao Jin Fang , Wang Yong Ze , Zhou Sheng De
Published: August 2013

Hydrolysis of the aquatic vegetables waste would lead to the generation of some toxic components and by-products, such as weak acids, aldehydes and phenols. They might do harm to sequent fermentation process to some extent. The toxic effect of acetic acid on ethanol fermentation by ethanologenic Escherichia coli SZ470 was investigated. The growth curves of Escherichia coli SZ470, specific growth rate (μ), the ethanol yield and consumption of glucose were compared with different concentrations of acetic acid addition in the fermentation medium. When concentrations of acetic acid exceed 0.8 g/L, the exponential growth phase of Escherichia coli SZ470 was significantly expanded from 10 h to above 12 h, moreover, the ethanol yield and consumption of glucose drastically decreased. Specific growth rate increased as acetic acid concentrations below 0.6 g/L, but fell as acetic acid concentrations exceeded 0.6 g/L, the result indicated that minor amount of acetic acid might be helpful with growth of Escherichia coli SZ470.
Effects of Urea Treatment on the Structure and Properties of Wheat Straw
Authors: Ma Xing Yuan , Yang Xi Ping , Zhang Shu Fang , Ma Jun
Published: August 2013

The article proved the effects of urea treatment on the structure and properties of wheat straw, using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), contact angle analyze (CAA) and thermal gravimetric analysis (TGA) other methods. The results show that the urea treatment of wheat straw epidermis and lignin chemical structure has undergone significant changes, most of the inorganic components of wheat straw has dissolved, making the cellulose from the lignin parcels released while the lignin from hard degradable mesh macromolecules into small molecules of a straight chain of easily biodegradable, so that the anaerobic microorganisms to the degradation of cellulose and lignin can be more easily.
Improving Biogas Production and Biodegradability of Acid Hydrolytic Cotton Stalk with Addition of Nutritive Salts and Complex Anaerobic Cellulose Decomposing Bacteria
Authors: Li Yan Bin , Zhang Qin , Sun Yong
Published: August 2013

Nutritive salts and complex anaerobic cellulose decomposing bacteria (CACDB) were added for anaerobic digestion process in order to improve biogas production and biodegradability of acid hydrolytic cotton stalk. The results showed that addition of CACDB, nutritive salt I and nutritive salt II could effectively enhance daily biogas production, cumulative biogas and methane yields, in this treatment, the total gas production, daily average gas production, TS gas production rate, VS gas production rate and average yield of methane were all highest and reached 5908.90 mL, 196.96 ± 7.97 mL·d-1, 143.07 ± 5.79 mL·g-1, 156.32 ± 6.33 mL·g-1, 102.58 ± 3.34 mL·d-1, separately. The addition of CACDB and nutritive salts could improve the biodegradability of acid hydrolytic cotton stalk, in all addition treatments, the degradation rates of cellulose and lignin, VS reduction rates were higher and C/N ratios were lower than control treatment. The SEM analysis showed that the microstructure changes of digestion residues were helpful for biogas production.
Pentosan Extraction from Poplar Treated by Green Liquid
Authors: Zhang Jun Ying , Zhou Jing Hui , Li Hai Ming , Han Ying , Shi Jun Feng
Published: August 2013

Green liquor, a process liquor of alkali recovery in pulp and papermaking industry, pretreatment used in poplar kraft pulping process and the influences of pretreatment conditions on pentosan extraction have been studied. The results show that the influence of green liquor dosage on pentosan extraction is the most remarkable, with temperature taking the second place and time the third. Under the conditions of liquor ratio 1:4, green liquor dosage 1.5 L/kg (based on oven dried material), temperature 100 °C, time 90 min, higher pentosan extraction ratio of 13.81% (based on the pentosan content of raw material) is achieved. The wood was pulped under normal KP conditions after pretreated by the optimal pentosan extraction conditions. Comparing two kinds of pulp with and without pretreatment at similar stock yield level, the results show that the former has a little lower viscosity, significantly decreased Kappa number and excellent paper physical properties.
Selective Pyrolysis Behaviors of Willow Catalyzed via Phosphoric Acid
Authors: Liu Jun Li , Jiang Jian Chun , Huang Hai Tao
Published: August 2013

Willow is an abundant plant in many countries all over the world. It has an extremely rapid growing rate, and it can be considered as a sustainable raw material wood resource. In this study, H3PO4 of catalyzed willow pyrolysis was investigated by means of CP-GC-MS. Moreover pyrolysis products such as furfural, levoglucosenone,levoglucosan and phenolic compounds was ananlyzed. The results indicate that H3PO4 shows increased selectivity towards sugar and furan compounds at the expense of acetic acid and phenolic compounds. The biomass treatment with H3PO4 enhances dehydration and decarbonylation of levoglucosan resulting in more furfural and levoglucosenone, promoting the lignin to form carbon rather than phenolic compounds. and inhibit acetic acid formation.. The content of the major sugar compounds reached 50% in the prensence of catalyst. The content of the major furan compounds enhanced, mainly furfural.
Study on Ethanol Production from Sweet Sorghum Straw
Authors: Sun Qing , Huang Shu He , Gu Shi Yan , Zhao Feng Qin , Ge Jing Feng , Yi Wei Ming
Published: August 2013

In this paper, the sweet sorghum straw by alkali pretreatment has been fermented to alcohol with synchronized hydrolysis and fermentation technology. According to the quadratic orthogonal rotating of four factors combination experimental design, the test studied the relationship between the nutrient additive amount about (NH4)2SO4, KH2PO4, MgSO4·7H2O, CaCl2 and alcohol yield, meanwhile this fermentation 1conditions were optimized. By analysis, these factors impacted alcohol yield and the mathematical equations has been established about four factors on the yield of alcohol. The results showed that a significant regression equation was obtained. The optimum conditions for alcohol yield are obtained, (NH4)2SO4 0.09 percent, KH2PO4 0.1 percent, MgSO4·7H2O 0.414 percent, CaCl2 0.385 percent, at this time alcohol yield is 13.07 percent (by weight).
Study on the Characteristics of the Aquatic Vegetables Waste Fermentation to Biogas
Authors: Wang Jin Hua , Xiong Yuan Yuan , Lei Yan Min , Zhao Jin Fang , Shi Yong
Published: August 2013

Biogas production efficiencies from sole aquatic vegetables waste and plus with straw were investigated in this research. The results as flowns:The biogas production of 3375 ml with 62% CH4 content was achieved when the ratio of the aquatic vegetables waste to the straw was 15:35 (g/g), which is much higher than the control using aquatic vegetables waste or straw as sole raw fermentation material to the extent of 15.85%-37.72%. And the volatile solids (VS) and total solids (TS) drastically change also be coincided with the biogas production. Which pyruvic acid, the acetic acid and citric acid content lower than that of control (the aquatic vegetables waste, the aquatic vegetables waste and the straw at ratio of 25:25 (g/g), the straw) 27.32%-44.35%, 37.77%-57.52%, 30.78%-46.52% respectely. The results implied that with certain proportions, aquatic vegetables waste can promote the biogas generated form straw fermentation.
Design and Implementation of Dual-Axis Solar Tracking System with GSM Fault Reporting Capability
Authors: Wu Yu En , Huang Kuo Chan
Published: August 2013

This paper presents a smart dual-axis solar tracking system, its architecture includes sensors, embedded controllers, AC motors, Integrated electric putter design biaxial institutions, and the GSM automatic report of fault notification, to achieve autonomous tracking solar track system and adjust the solar panels to reach the maximum smooth by tracking the solar azimuth angle and elevation angle, and ensure that the solar panels with the sun to maintain the vertical in any time and any place, thus achieving the best power efficiency. This system proposed a dual-axis design, and an embedded controller used as the main system controller to detect voltage difference and determine the solar azimuth angle with four groups of CDS as a sensing element. To lock the sun, the solar panels be perpendicular via the moving of AC motor (EW) and motorized faders (north-south). The control system software using C language can be extremely fast and accurate tracking of the solar angle, and dual-axis operation with recovery mode to save the power loss. Finally, we have the actual analysis and verification of benefit of power generation in this paper, from this experimental results, we can verify the integration of build dual-axis solar tracking system and solar power system have promoted 30% generating power capacity more than fixed solar power system and has low failure rate. It can improve the problem of traditional tracking system reliability and greatly enhance the usefulness of this system.
The Biological Sources of the Organic Matter in Poyang Lake Sediments
Authors: Yang Ming Sheng
Published: August 2013

We conducts a systematic study on the biological sources of the sediment organic matter through the analysis of the organic carbon and nitrogen content in the sediments of Poyang Lake, the n-alkanes as biomarker and the characteristics of the compound-specific isotope of n-alkanes. It is found that the C/N ratio of organic matter is less than 10 in Poyang Lake and that the organic matter mainly originates from lacustrine aquatic organism. The short-chain hydrocarbon takes absolute advantage in the n-alkanes. The value of C21-/C22+ is greater than 1, which shows that the biomass of bacteria and algae is greater than the sum of the aquatic submerged plants and terrigenous organisms biomass. The value of (nC15+nC17)/(nC23+nC25) of n-alkanes is greater than 2, which reveals that bacteria and algae have an absolute predominance in aquatic organism. The high carbon n-alkanes come from terrigenous plants and their compound-specific carbon isotope demonstrates that C3 plant is the main biological source.
The Cultivation Technique for Increasing the Stalk Sugar Content of Energy Plant Sweet Sorghum in Yellow River Delta
Authors: Ding Tong Lou , Song Jie , Guo Jian Rong , Sui Na , Fan Hai , Chen Min , Wang Bao Shan
Published: August 2013

This study was carried out to investigate the suitable technique for increasing the stalk sugar content of two sweet sorghum cultivars (salt-tolerant cultivar Jitianza 2 and salt-sensitive cultivar Lvneng 1) in saline soils of Yellow River Delta. Stalk sugar content of sweet sorghum in saline soil was significantly increased using the following integrated cultivation technique: (1) increasing organic fertilizer level; (2) applying optimum phosphorus and potassium fertilizer; (3) surface fertilizer application; (4) cultivating salt-tolerant sweet sorghum cultivars; (5) planting with plastic mulching; (6) planting in the early of the optimum seedling time (sowing as early as possible); (7) removing tillers during seedling stage; (8) cutting spike by half-strength before flowering. Jitianza 2 had higher stalk Brix than Lvneng 1 under the same cultivation condition. Therefore, planting salt-tolerant sweet sorghum cultivars in saline soil combined with these integrated cultivation techniques can get higher stalk sugar content in Yellow River Delta of China, which was beneficial for energy alcohol production from sweet sorghum.
Elevated N Supply Reduces the Inhibition of Growth and Photosynthesis Caused by Salinity in the Bioenergy Plant Hybrid Pennisetum
Authors: Chen Min , Wang Dian , Song Jie , Chen Tian Shu , Sui Na , Wang Bao Shan
Published: August 2013

Hybrid Pennisetum (Pennisetum americanum × P. purpureum) is a popular bioenergy grass that could also serve as forage for livestock production. In a pot experiment, salinity inhibited hybrid Pennisetum growth, photosynthesis, soluble sugar content, and NR activity; decreased K+ content; and increased Na+ content. These adverse effects of soil salinity were reduced, however, by applications of NO3--N up to 5 mmol·L-1; higher applications of NO3--N increased soil salinity problems. These findings will be useful for the production of hybrid Pennisetum as a biofuel on saline land.
Study on Characteristics of Ammonium Nitrogen Adsorption by Biochar Prepared in Different Temperature
Authors: Liu Ning , Zhou Chong Jun , Fu Shi Feng , Ashraf Muhammad Imran , Zhao En Feng , Shi Hui , Han Xiao Ri , Hong Zhi Bai
Published: August 2013

A model was prepared for the preparation of biochar from the biomass of mushroom residue at different carbonization temperature (350 °C,450 °Cand 550 °C) for adsorption characteristics of ammonium nitrogen in water through different ammonium nitrogen concentration, reaction time, pH and temperature. The investigation result showed that the adsorptive amount of these three biochar substances increased quickly with the initial concentration (0-2 h) and the adsorption equilibrium was reached after 4 hours. The adsorptive amount of these three biochars increased with the rise of pH from 5 to 9. Different temperature preparation of biochar on ammonium nitrogen adsorption increases with the rise of temperature. Different temperature preparation of biochar on ammonium nitrogen adsorption amount is in the order of 550 °Cbiochar > 450 °Cbiochar > 350 °Cbiochar.
A Wind-Thermal Hydropower Coordination Control Strategy Based on Multiple Constraints of Large-Scale Wind Power Integration
Authors: Wang Jian Bo , Liu Wen Ying , Zheng Wei , Liang Chen
Published: August 2013

Due to the fluctuations and intermittency of wind power, large-scale wind farms integration will cause adverse impact on the safety and stability of the system,such as harmonic pollution, bad power quality, system stability destruction.On the basis of multiple constraints, including hydropower’s and thermal power’s operating characteristics, determination of reserve capacity considering wind power forecasting bias, climbing speed constraints, and maximum output constraints, this paper proposed a control strategy of joint coordination of wind, hydropower and thermal power, which suppressed the fluctuations of wind power effectively. At last, the article give a simulation to verify the feasibility of the control strategy to stabilize system frequency.
An Investigation of the Low Performance of the First Wind Farm in Thailand: A Case of Poor Wind Turbine-Site Matching
Authors: Janon Akraphon , Wongwuttanasatian Tanakorn , Faikaow Gumphol , Srinor Panumas
Published: August 2013

This research investigates causes of the low performance of the first commercial wind farm in Thailand. The measured data suggests that this wind farm is uncompetitive. We found that this is due to poor turbine-site matching. In contrary to a traditionally held belief, the hub-height and turbine capacity are not the contributing factors. Key performance indicators are obtained for use as benchmarks in future wind farm appraisal. Then a turbine selection method is proposed to increase the capacity factor (CF) of the wind farm. CF is used as the main performance indicator, which can be compared to other wind farms. The real capacity factor (CFR) determined using measured data is 14.90%. This CFR is considerably lower than the estimated capacity factor (CFE) of 21.53%. The low CFR is due to grid instability. In addition, the CFR is lower than the CFE by a factor of 0.69. This information is valuable to investors and wind farm developers in a wind farm feasibility study. A graphical wind turbine-site matching is proposed. Wind turbine-site matching is achieved by using normalised power output plots and power density plots on a probability density graph of the wind site. This process consumes a short period of time. An improved turbine-site matching is achieved.
Modeling and Simulation of the Brushless Double Rotor Motor for the Novel Wind Power Generation System
Authors: Fu Lan Fang , Wang Hua Jun , Sun He Xu
Published: August 2013

A novel driver concept has been developed to meet the grid requirements. A regulation speed device was connected to a variable speed gearbox with a constant speed synchronous generator.A brushless double rotor motor based on a novel wind power generation system is proposed. The motors structure , principle and mathematic model are studied.The simulation results show that brushless double rotor motor is suitable as a regulation speed device to apply to the novel wind power generation system.
Offset-Free Model Predictive Control for Wind Power Generation Systems
Authors: Wang Xiao Lan , Ye Li Sha
Published: August 2013

Due to wind power generation system (WGS) is strongly nonlinear, multi-input multi-output and with high turbulent disturbance, we build a offset-free model considering system noise and measurement noise and its predictive controller for all operating area from cut-in speed to the cut-out wind speed. Finally we predict the optimum generator torque and pitch control signal. By add damping mode in drive train using torque control, the purpose of smoother power and less torsional torque pulsation on drive train are achieved. Simulation results shows that this predictive controller is able to reduce the impact of noise and interference on the system, ensuring constant power output and reducing the torque pulsation.
Study on Different Impacts on the Reliability of Grid Connecting with the Offshore and Onshore Wind Farms
Authors: Xu Xuan , Zeng Yuan , Wang Xin Ze , Li Peng , Zhang Yong
Published: August 2013

As the wind power penetration continues to increase, one of the main challenges faced in power operation is to maintain the system reliability when committing an appropriate amount of power from a wind farm in the lead time. This paper presents an approximate model for estimating offshore winds in the domain of meteorology, raising the accuracy and comparability between offshore and onshore wind power. And then, considering the discrepancy in wind speed fluctuations between offshore and onshore sites and difference in operation characteristics between double-fed induction generators and permanent magnet synchronous generators, this paper studied the different influences on the reserve capacity due to the offshore and onshore wind farms committing the power system. Comparing with the onshore wind farms, offshore wind farms have more positive effective on the reliability of the grid and are suitable for more economic operation scheme.
The Wind Power Industry in China: Status and Issues
Authors: Yuan Jia Hai , Sun Sheng Hui
Published: August 2013

With the incentive and supporting policy of the government, wind power industry has experienced swift development and gradually moved towards maturity in China. In this paper, we review the status of the wind power industry in China from a supply chain perspective, there is mismatching between upstream and downstream. In the upstream the production capacity takes the lead but the R&D capability is weak in the world. In the downstream the speed of wind farm development is fastest in the world but the capacity of wind power integration and absorption is restricting the utilization and development of wind farm. We analyze the issues with the supply chain from a macroscopic view and the policy recommendations for optimizing the development of wind power in China are proposed.
Exploration of Composite Solar and Wind Power Generation Device Control
Authors: Zhang Lian Zhong
Published: August 2013

Recently, Solar energy and wind energy composite wind turbine by a number of studies have been carried out to examine the fault-ride through capability of the DFIG system during network disturbance. Whereas for all the work reported, the network voltage was assumed to be symmetrical. However, in practice, asymmetric faults occur more frequently than symmetric ones. For a DFIG system, if the voltage unbalance is not considered in the control system, the stator current could be highly unbalanced even with a small unbalanced stator voltage. The unbalanced currents create unequal heating among stator windings and torque pulsation in the generator. A wind-turbine driven DFIG without unbalancing voltage control considered might have to be disconnected from the network during network voltage unbalance.
Peak-Load Regulating Adequacy Evaluation in Wind Power Accessed System Considering the Correlation of Wind Farms
Authors: Li Yi Long , You Da Hai , Wang Ke , Tian Ke , Pan Kai
Published: August 2013

There is a certain degree of correlation between the outputs of different wind farms because of their geographic distribution in power grid. And the complementary effect can alleviate the adverse effects of peak-load regulation caused by the large-scale wind power integration. In this paper, Nataf transformation was used to establish wind speed samples of correlative wind farms to get correlative wind power. Based on this, the peak-load regulating adequacy was evaluated using Monte-Carlo method on IEEE-RTS system with wind farms. The result presents the quantitative analysis of the impact of correlative wind farms on peak-load regulating adequacy. And it improves the original peak-load regulating adequacy evaluation based on Monte-Carlo method, which has the relatively conservative results.
A Study on Water Pumping by Using a Small Multi-Blades Windmill for Used in a Remote Area
Authors: Keawsuntia Yuttachai
Published: August 2013

The objective of this research is to study the small multi-blades windmill for water pumping by using a studying performance of windmill which has a curvature plate ratio of 0.07 and determine overall efficiency and evaluate economic of the system. The results from the test run of windmill rotor model in the wind tunnel at a wind velocity of 3 m/s, the windmill give maximum power coefficient of 0.296 at a tip speed ratio of 1.18. The results from the test run of the windmill-pump system at 2 m head have an overall efficiency of 0.239 at the wind velocity of 1.2 m/s. The output of 2.38 L/min, which implies a rate of return for water pumping at 0.038 USD per cubicmetre of water base on 10 year-life time of windmill.
China Wind Power Development Status and Trends
Authors: Liu Dong Bo
Published: August 2013

Compared to nuclear power, wind power has a short construction period, high security, rich in resources and other advantages; compared to photovoltaic power generation, wind power has the power and low cost advantages. Over the past five years, benefit from the support of the localization rate and other policies, the average annual wind power in China compound growth rate of 101%, wind power industry chain upstream parts manufacturing localization, spindle bearings, control systems also need to be imported; midstream machine manufacturing market dominated by domestic-funded enterprises; downstream wind power operators also see five power generation groups, led by the central enterprises the wind turbine increasing unit capacity of 1.5MW and above the level of wind turbine occupy a major share of the market, the development of wind power is inseparable from the support of the policy. Offshore wind power has high feed-in tariff, high throughput advantage of offshore wind power will become a growth point of the wind power industry in the future.
Optimal Design for Photovoltaic and Photothermal Hybrid Solar Cells of Solar Powered Aircraft
Authors: Sun Kang Wen , Ni Min
Published: August 2013

Cell temperature can reach as high as 70 oC while working, using only photovoltaic battery in the solar plane will result in a waste of energy. Combined with the wing configuration, a hybrid energy design method with higher efficiency is presented: photovoltaic cells will be distributed on the wing surface and photothermal cells will be arranged in the wing box section. The back of photovoltaic battery can be used as high temperature heat source and the lower wing surface can be a low temperature cooling source. Through the research of photovoltaic cells maximum power output, the envelope method ensures the output power, improves the power tracking reliability, and reduces difficulty in the design. The structure design of thermoelectric battery P-N junction is optimized by using the maximum power and maximum power to-mass ratio as objective function. The optimal solution of P-N junction structure of a certain type thermoelectric battery is given for acquiring maximum power-to-mass ratio.