bluuebunny/crossref_metadata_2025 huggingface dataset:
Laboratory Analysis for Investigating the Impact of Compaction on the Properties of Pervious Concrete Mixtures for Road Pavements
Authors: Bonicelli Alessandra , Crispino Maurizio , Giustozzi Filippo , Shink Melanie
Published: August 2013

Pervious concrete is a relatively new material, standards and rigorous specifications for construction and placement are therefore still missing. One the one hand, the main characteristic to achieve is a high permeability to allow meteoric water percolate in the pavement and evaporate from the subgrade. On the other hand, developing pavement cementitious mixtures able to retain high void contents and reach significant mechanical performance entails an in-depth analysis of materials and construction practices. Pervious concrete can indeed be placed using a standard paver as for asphalt mixtures but the compaction stage is usually demanded to the contractor practices: light steel hand-rollers or standard drum rollers are both used without an in-depth knowledge of compaction properties of the cementitious mixture. The present paper aims at investigating the influence of compaction methods on the mechanical performance and void contents of pervious concrete mixtures. Several compaction procedures were tested modifying the compaction energy and the mixture characteristics while preserving high permeability. The main objective was to simulate and identify the effect of commonly adopted in situ compaction techniques - i.e.: tamper compaction as provided by the paver, steel hand-roller compaction, or standard drum roller compaction. Results showed how the compaction energy, water/cement ratios, and the percentage of cement affect the Indirect Tensile Strength and void contents of the mixtures. Further investigations were also conducted in order to comprehensively evaluate how the variation in the percentage of cement and water/cement ratio influenced the stiffness of the material.
Design and Evaluation of Ultra Thin Friction Courses Asphalt Mixture Modified by Polyolefin
Authors: Guan Yong Sheng , An Feng Wei , Han Chao , Zhang Zhi Xiang
Published: August 2013

Because of the small thickness, the mixture temperature of Ultra Thin Friction Courses (UTFC) decreased quickly during construction process, which causes the great difficulty to guarantee the pavement compaction, especially for the dense gradation asphalt mixture. In order to solve this problem, Polyolefin and SBS modified asphalt (Abbrev. PSA) mixture was designed. Volumetric properties, compaction characteristics, water sensitivity, as well as high/low temperature performance of the mixture were investigated. Laboratory test results show the PSA mixture has very good high temperature performance and other beneficial characteristics. Field tests show that the new asphalt mixture possesses very good pavement performance, as well as easily to be constructed. The PSA mixture can be used as preventive maintenance and repair materials.
Resistance to Permanent Deformation of Road and Airport High Performance Asphalt Concrete Base Courses
Authors: Pasetto Marco , Baldo Nicola
Published: August 2013

The paper discusses the results of a laboratory investigation aimed at analyzing the rutting susceptibility of high performance asphalt concretes, made with three different bituminous binders and four types of artificial and recycled aggregates (steel slags, glass wastes, municipal solid waste incineration bottom ash and coal ash), used in partial substitution of the natural limestone. The experimental study has been focused on the characterization of the physical-mechanical properties of the marginal materials, as well as on the volumetric mix design and the permanent deformation evaluation (by means of Creep Recovery Tests, Repeated Load Axial Tests, Wheel Tracking Tests) of bituminous mixtures for road and airport asphalt concrete base courses. Because the requisites for acceptance in the Italian Specifications and Standards have been satisfied and given the positive mechanical performance (indirect tensile strength at 25°C on dry and wet samples up to 1.27 MPa and 1.07 MPa respectively), it has been verified that the marginal aggregates investigated can be used as substitution of the lithic materials in the base courses, also with very high content (up to 70% on the weight of the aggregates).
Viscoelastic Properties of Field-Aged Cores
Authors: Meng Ling
Published: August 2013

Nowadays, engineers begin to pay more attention on field-aged asphalt concrete cores because they have more reality than the lab-made cores and the results can tell what happened to the pavement. However, it is not accurate to estimate the full asphalt mixture because as usual the pavement engineers can only extract the binder from it, not the mixture. Now there is a newly developed way to analysis the data more accurately using the Direct Tension Test. Because the field aged asphalt mixtures are not aged uniformly with the pavement depth because of various reasons, there is a modulus gradient going through deeply through the asphalt layer and usually the stiffest layer is the surface because normally the surface is more aged. A method has been developed to analysis this behavior. Tests are both taken on field cores which are Hot Mix Asphalt (HMA) and Warm Mix Asphalt (WMA). During the research, the authors found that it is both applicable for all the field cores. More information about this method and tests are detailed in the following paragraphs.
A Review of Harvesting Green Energy from Road
Authors: Zhao Hong Duo , Ling Jiang Ming , Fu Peng Cheng
Published: August 2013

This paper presents a review of harvesting green energy from road. There are three forms of green energy exist in road: light, thermal and mechanical energy. Photovoltaic technology, thermoelectric technology, directly heat transferring and piezoelectric technology are discussed in this paper, as well as the cases studied in Europe, USA, Japan, Israel and China. Solar panels installed along road are current available to harvest light energy from the roadside land. Alternatively, the solar panels can be installed on the road instead of pavement structures, such as the Solar RoadwayTM. This technology is rather conceptual at this moment, and the main challenge is to design and build durable materials and structures that can withstand traffic at a reasonable maintenance and replacement cost. Thermoelectric generators can potentially be embedded in pavements, and generate electric power from the temperature gradient existing in pavements. However, instrument capable of efficiently generate electricity from the relatively small temperature gradient in pavement is still under development. Directly heat transfer solution is to have fluid flow through pavement, and the fluid is heated (in summer) by the pavement. An extra benefit in addition to energy collection is that this method can reduce pavement temperature as well as the associated negative effects on pavement performance and the environment. However how the heated fluid can be utilized was not clear. Electricity can be generated by piezoelectric ceramic generators embedded in pavement, as a result of the compressive stress and deformation induced by moving vehicles. Trials have been reported in Israel and China, and it was estimated that one lane-mile of highway can potentially general electricity of 200 kW.
Eight Kind of Typical Asphalt Pavement's Applicability Research for Northern Warm Zone Continental Climate Regions
Authors: Guo Zhong Yin , Li Shao Hui , Yang Yong Shun
Published: August 2013

in order to find a suitable pavement and develop a reasonable pavement design method for southern warm continental climate regions, both experiment roads and finite element simulations are employed in this research. In experiment roads, strain detectors are buried at the bottom of asphalt layers to measure its strains and calculation models. Road design parameters such as road surface deflections and damage predictions such as plastic permanent deformations are calculated and compared between different pavements. Pavement deformation and design control parameter are made. Finally, a suggested reasonable pavement satisfying climate conditions and traffic flow needs is proposed.
Settlement Isolation Susceptibility due to Heavy Rain Caused Road Closure
Authors: Yang Shu Rong
Published: August 2013

On August 9, 2009, Typhoon Morakot struck Taiwan, triggering landslides and debris flows and destroying transportation infrastructure in the southern mountains. Many settlements in this area were isolated due to road closure. Residents were trapped in the settlements and unable to evacuate to safe places. Also, emergency goods were unable to be transported to the settlements. In order to minimize the loss of life and property associated with future typhoon, public administrators should evacuate residents before access routes to settlements are affected.In this study, settlements in Lao-Nong River basin of Southern Taiwan were ranked in accordance to isolation susceptibility. Susceptibility was estimated by overlaying maps of landslides, debris flows, temporary roads and primary mountain road layers. Criteria used to evaluate the isolation susceptibility were developed using an expert-based approach. The isolation susceptibilities of settlements were categorized into 3 levels, namely high, moderate and low.
Study on the Recycling Method for Drainage Asphalt Pavement and Evaluation for its Durability
Authors: Kawakami Atsushi , Kubo Kazuyuki , Sasaki Iwao , Kano Takashi
Published: August 2013

In Japan, drainage asphalt pavement (DAP) is widely used especially on the highway and the express way. However, because of the existing porous asphalt materials consist of DAP use polymer modified bitumen, and the aggregate gradation of DAP is differ from conventional mixture, it is difficult to use those porous asphalt materials as the recycled aggregate for reclaimed asphalt pavement. Therefore, the recycling method for recycled DAP which were consisted of recycled porous asphalt materials and virgin aggregates has not been established yet. This paper describes that the recycling method for recycled DAP was considered, and the workability and five years durability was also verified by trial construction of the recycle DAP and new DAP which were consisted of virgin aggregate on the national highway.
The Study of Pavement Surface Temperature Behavior of Different Permeable Pavement Materials during Summer Time
Authors: Lin Jyh Dong , Hsu Chen Yu , Paramitha Putri Adhitana , Lee Jeng Ching
Published: August 2013

This study explored the thermal behavior of permeable pavement during summer. T-type thermo-couple needle was utilized to measure the surface temperature of three different permeable pavement materials. Data were measured based upon the 24 solar terms of the traditional Chinese lunisolar calendar and the results of Great Heat in comparison with other solar terms showed significant differences. Heat output model calculation results show that the average heat output is the lowest for grass bricks because of its high reflectivity. This material has a cooling effect, followed by permeable interlocking bricks. Permeable asphalt concrete can reduce pavement temperature but there were limitations to its performance.
Quantifying Overall Performance of Highway Design, Construction, and M&R Practices Using ECC & ASL
Authors: Tsai Yi Chang James , Cui Bu Xin , Xu Ying , Wang Di
Published: August 2013

Developing a method that quantitatively evaluates and compares the overall performance from economic (agency) and user service perspectives of the highways constructed with different designs, different construction practices, in different places with different environments, and under different traffic conditions with different Maintenance and Rehabilitation (M&R) histories, has been challenging. The factors (costs, effectiveness and traffic volume) are studied in this paper and then an economic and user service-based performance measure method is proposed to identify high or low pavement overall performance. The two indicators, Equivalent Comprehensive Cost (ECC) and an Average Service Level (ASL), in this method are proposed to evaluate the unit agency costs and average service level over the analysis period of the project quantitatively. Two different pavement projects were generated with hypothetical data to illustrate the ability of the proposed method to compare the overall performance of different projects, and a sensitivity analysis of the discount rate was also studied and discussed. Future research is recommended.
Development of Pavement Condition Rating Model and Pavement Roughness Model for Saudi Highways
Authors: Mubaraki Muhammad
Published: August 2013

The Pavement Condition Rating (PCR) has been used by the Ministry of Transport (MOT) in Saudi Arabia to report pavement condition. The World Bank developed the PCR in 1986. PCR is based on International Roughness Index (IRI), Rutting (RUT), Cracking (CRA), and Raveling (RAV). The MOT collects pavement condition data using a digital inspection vehicle called Road Surface Tester (RST) vehicle. On some expressways, the MOT measures the Skid Number (SN) using a Skid Test Unit as complimentary measurement for safety issues. The objective of this paper is to develop PCR model and pavement roughness model using survey data for overlaid sections on some expressways in the network with total observation number is 3469. The PCR model is a function of pavement age (T), Traffic Volume (TV), and IRI. The IRI model is a function of RUT, RAV, and CRA. Overlaid sections across the entire network have been selected to study the mechanisms of pavement deterioration, to develop the model and to draw conclusions.
Establishment of Pavement Information Decision Management Platform via Cloud Computing Technology
Authors: Yang Chih Chung , Lin Jyh Dong
Published: August 2013

With the time progress and constant promotion of information technology, the living quality of people is improved relative to economic development and people constantly demand the government to improve service effectiveness. In order to save manpower and material resources, it is an inevitable trend for road authorities to develop pavement management system of government electronization. However, the existing pavement management systems at home mainly comprise basic investigation data on road condition, current situation analysis and suggestion of maintenance threshold, road maintenance priority decision analysis and other management purposes, so as to promote the efficiency and quality of pavement management operation. While, most of the systems have the disadvantages of different maintenance planning decision making approaches, insufficient project construction history data, chaotic use of drawings, too little available knowledge, failure to integrate information and so on, so it is unable to establish an effective system to assist engineers as the control function, which causes a major obstacle relative to the development of pavement management system. The loss of pavement engineering history data with time would cause difficulty in data collection for future pavement analysis. Therefore, how to resolve the above problems becomes a major assistance for the future pavement maintenance knowledge decision management. The study establishes cloud computing pavement information decision management platform in the form of implementation via Google public cloud computing, validates the feasibility through practical cases, utilizes cloud drive real-time data processing, electronic document management, graphical pavement information and figuration management analysis through the software provided by Google, improves the budget for control efficiency and enhances the promotion of pavement management system, so as to accord with the study objective.
Evaluation of Effects of Priority Preferences on Optimal Resource Allocation in Pavement Management
Authors: Farhan Javed , Fwa Tien Fang
Published: August 2013

Certain aspects of prioritization have commonly been employed in the optimum resource allocation program for pavement maintenance management. However, issues associated with incorporating priority preferences into pavement maintenance programming have not been evaluated. For example, application of priority weights to certain problem parameters will affect the optimality of the end solution with respect to the original objective. However, the degree of loss in optimality is related to the form or structure, the magnitudes, and the range of priority weights adopted. Decision makers, who adopt such an approach, are often oblivious to the degree of sub-optimality of the solutions. Therefore, this paper presents a study that examines the implications of applying priority weights, of varying magnitudes and ranges, in the pavement maintenance programming analysis in terms of optimality of the solution/strategy.
The Study of HDM-4 Applied in Taiwan Area National Freeway Maintenance and Management
Authors: Chen Yung Lin , Lin Jyh Dong
Published: August 2013

Taiwan Highway System experiences successively investment of few decades in government. After the first national highway-Chung Shan, the Second national highway, twelve west to east freeway and western seaside freeway go to operation, the road network is gradually complete. The road engineering changes the style from new construction to maintenance management. In recent years, because the government public construction budget reduce year by year, so road agencies should be emphasizing facilities management and enhancing construction performance that keeping highway transits service quality with the constraints of budget limitations. World Bank carries on a series of project researches to the road in 1968 and develops the related evaluation module. In HDM-4, it provides the extensive module application and explicit method in the stages such as planning, programming, preparation and operation etc. It provides a reference that road agencies carry on related decision. HDM-4 provide user to adjusting with different region parameter such as weather, environment...etc. So this tool can be applicable to more widespread region. When the related pavement maintenance systems are not satisfactory, how to use the international identify tool help Taiwans highway maintenance management. It is very interesting and workable research. We use HDM-4 to collect and analyze Guan-Xi regions Highway No.3 network data, traffic characteristic and cost related information. Through this knowledge, we can adjust the HDM-4s parameter to suit Taiwans condition. Besides, we review technical literature and experts experience to determine on maintenance alternates. We use adjusted mode with real highway budget to determine the threshold of routine and period maintenance. Considering maintenance cost, user cost and highway economy to decide suitable threshold. Finally, base on the best maintenance strategies to explain the relation between maintenance budget and performance. Base on this result, we can determine the budget allotting criteria to reach the biggest economy benefit of the resource.
Threshold-Based Maintenance Optimization for Pavement Infrastructure Using Hybrid Dynamic Modeling
Authors: Chu James C. , Li Ming Hsien , Chen Shih Chi
Published: August 2013

This study adopts hybrid dynamic modeling (HDM) to simulate and optimize threshold-based pavement maintenance. To evaluate the quality of the optimized threshold-based maintenance, benchmark plans are also generated by relaxing the threshold-based strategies. The proposed methodology is demonstrated with a network of 20 highway pavements. Based on the numerical results, some guidelines for selecting maintenance strategies in different scenarios such as budget availability are proposed.
Bidding Decision Model Based on Prospect Theory and Game Theory
Authors: Cheng Min Yuan , Hsiang Chia Chi
Published: August 2013

In the construction industry, most of the owners apply competitive bidding to award a contract to the lowest price qualified contractor. This study proposes a model concerning the preferences and the behaviors of all decision makers whom participation in an competitive bidding to assist contractors to make optimal bidding strategy decisions and set appropriate bidding prices. Researchers demonstrated model applicability using an actual case study, which shows how this model help the construction company’s primary decision maker to determine the appropriate bidding price in a multi-competitors condition.
Stabilization of Artificial Organic Soil at Room Temperature Using Blended Lime Zeolite
Authors: Ling Felix Ngee Leh , Kassim Khairul Anuar , Abdul Karim Ahmad Tarmizi , Chan Tze Wei
Published: August 2013

Organic content in soil is believed to inhibit formation of reaction products in lime stabilization which resulted in low gain of strength when dealing with organic soils. Zeolite, a kind of pozzolan with high CEC capacity is proposed to be use in this study in order to improve lime stabilization of organic soil. The effectiveness of blended lime zeolite in stabilization of organic soils was investigated by using two types of artificial organic soils with predetermined organic contents. Artificial organic soils were formed by mixing inorganic soil (commercial kaolin) with organic matter (commercial humic acid) at specific ratio. Initial consumption of lime for organic soils was determined in order to determine the minimum percentage of stabilizer required for each soil. Potential influencing factors that might affect the strength such as organic contents, contents of stabilizer, and curing periods were studied. The findings of the study showed that high organic contents and low lime contents resulted in lower gain of strength. However, it is found that slight replacement of lime with zeolite works well with low organic soil at long curing period which resulted in highest strength among all the mixes. Overall, longer curing periods will increase the strength of the soil in the order of 56 days > 28 days > 7 days. Nevertheless, the percentage of strength increment over curing periods is linear with the lime contents, which proved that lime is required for pozzolanic reaction.
The Analysis of Solar-Earth Source Heat Pump Combined Operating
Authors: Zhang Jian , He Jing Jing
Published: August 2013

This article describes the solar - earth source heat pump system characteristics and operating principles, the various operating modes of the system are discussed, and the system applied in Lanzhou region were analyzed. Pointed out that the relatively rich regions in the solar promote the use of solar - earth source heat pump technology has good prospects for development.
Abnormal Heat Triggered by Pressure Change in a D/Pd Gas-Loading System
Authors: Wang Hong Yu , Zhao Xin Le , Shen Bing Jun , Jin Li Hong , Lu Xin , Tian Jian
Published: August 2013

This article by palladium deuterium gas-solid experimental system design, combined with the DH1716A program-controlled DC stabilized current supply and Keithley 2700 data acquisition and recording system, respectively at five different pressures, pressures triggered by experimental methods, making experiments of deuterated Palladium chemical reactions within the system, resulting in a tile level under different pressures is overheating.
Crystallitic Structure and Thermodynamics of Magnesium-Based Hydrogen Storage Materials from Reactive Milling under Hydrogen Atmosphere
Authors: Zhou Shi Xue , Zhang Qian Qian , Wang Nai Fei , Han Zong Ying , Ran Wei Xian , Li Chang Zhen , Ding Chao , Li Peng Bo
Published: August 2013

Magnesium-based hydrogen storage materials were prepared by reactive milling of magnesium under hydrogen atmosphere with crystallitic carbon, prepared from anthracite coal, as milling aid. The XRD analysis shows that in the presence of 30 wt.% of crystallitic carbon, the Mg easily hydrided into β-MgH2 of crystal grain size 29.7 nm and a small amount of γ-MgH2 after 3 h of milling under 1 MPa H2. The enthalpy and entropy changes of the hydrogen desorption reaction are 42.7 kJ/mol and 80.7 J/mol K, respectively, calculated by the vant Hoff equation from the p-C-T data in 300-380°C.
Magnesium Hydride of Orthorhombic Crystal from High-Energy Ball Milling under Hydrogen Atmosphere
Authors: Zhou Shi Xue , Ran Wei Xian , Yang Min Jian , Wang De Xi , Chen Guo Qiang , Zhang Ye , Han Zong Ying , Zhang Qian Qian
Published: August 2013

The crystal structure of magnesium hydride affects the properties of magnesium for hydrogen storage. The crystal phase and dehydriding temperature of magnesium hydride from magnesium by high-energy ball milling under hydrogen atmosphere with anthracite carbon, which was prepared from anthracite coal by demineralization and carbonization, as milling aid was investigated. The HRTEM observation and XRD characterization showed that the Mg hydrided into nanocrystalline β-MgH2 of tetrahedral crystal structure and γ-MgH2 of orthorhombic crystal structure during milling under 1 MPa of hydrogen, and the γ-MgH2 increased with the extension of milling time. The DSC analysis showed that the endothermic peak of γ-MgH2 was 53 °C lower than that of β-MgH2 in the material from 10 h of milling.
Sol-Gel Synthesis of LiFePO4/C Composite Cathode Material from FePO4/PANI
Authors: Cheng Zhong Yuan , Zhong Fu Xin , Jiang Ying , Yu Peng Fei , Jin Yun Xia , Xiao Shun Hua
Published: August 2013

Olivine structured LiFePO4 are prepared by sol-gel method from FePO4·H2O nanocrystallites, which are synthesized via in situ polymerization restriction technique. These composites are fully characterized using XRD, SEM, and the electrochemical performances have been shown by the charge/discharge capacity, rate property and cycle performance. The synthesized LiFePO4 samples show well-crystallized structures. Among those samples, the sample synthesized at 650°C presents the highest discharge capacity of 165.8 mAhg-1 at 0.2 C. This compares with a theoretical discharge capacity of 170 mAhg-1.
Analysis of Extraction of Coal Oxidation Residue in NaOCl
Authors: Gong Gui Zhen , Chu Ji Ming , Wei Xian Yong , Zong Zhi Min
Published: August 2013

Sequential extraction of four coal oxidation residues (COR) from aqueous NaOCl solution with petroleum ether (PE), carbon disulfide (CS2), acetone and methanol were investigated. The results suggest that methanol is an effective extraction solvent, giving the highest extraction yields for four COR. The extraction fractions were analyzed by GC/MS. It is found that no compounds, except for F1 of HL and XL , F2 of four COR, were detected. In total, 89 organic compounds were detected in F1 of HL and XL, 23 organic compounds in F2 from four COR. Most of which were arenes (As), normal alkanes (NAs) and oxygen-containing compounds (OCCs).
Effects of Fuel Supply Advance Angle on Engine Thermal Efficiency and Emission Performance Fueled with Bio-Diesel
Authors: Zeng Qi
Published: August 2013

Having comparison test research of economy and emission characteristics of biodiesel under different fuel supply advance angle on L16-type single cylinder diesel engine. The results show that the diesel engine has good effective thermal efficiency and economy with the fuel supply advance angle at 17°CA-BTDC; CO emissions basically increases with the decrease of fuel supply advance angle; NOx emissions increases with the fuel supply advance angle; THC emissions show not obvious and complex variation trend with the change of fuel supply advance angle, but the magnitude of the overall change is not obvious; with the decrease of fuel supply advance angle, Soot emissions increase first and then decreases.
Process Improvement of a 1Mt/a Gasoline and Diesel Hydrofining Unit for Energy-Saving (II)
Authors: Wu Shi Kui , Xu Kai Xiong , Wang Li , Wei Qi Ji
Published: August 2013

The operation of a 1Mt/a gasoline and diesel hydrofining unit was performed through some energy-saving optimization. The process improvement measures include: ① Change the blending process of the recycle stock; ② Improve the thermal efficiency of the reaction part; ③ Decrease the energy consumption of the fractionation reboiler part. According to the process improvement measures above, 560 tons of standard coal per year were expected to be saved for the company. They are also beneficial for the safe operation of the apparatus.
Impact Analysis of Integration of Coal Resources on China's Energy Security
Authors: Zhang Yan , Shen Lei , Shi Min Jun
Published: August 2013

This paper brieflyintroduced the countries all over the world and China's energy securitysituation of coal resources. According to the international development trend,it is imperative to integration coal resources in China. Analysis of theproblems and solutions encountered in the integration of coal resources inShanxi Province, With the gradual integration of coal resources in ShanxiProvince, that a nationwide coal resources integration will subsequentlycommence. Establish a scientific and rational policy-oriented, has an importantpractical significance for China's energy security and industrial architecture.
Development and Utilization of Green Energy in Hanjiang River Basin: Example from Xiangyang Section
Authors: Li Xia
Published: August 2013

Hanjiang River Basin Development is an important strategy in China. Xiangyang is one of the core cities on the verge of Hanjiang, occupying important place in the development in Hanjing River basin.The thesis analyze the present situation of Green energy development and utilization in Xiangyang, and then summarize main problems from utilization level, support policies, difficulties in grid-connected systems and consumption shortage and put forward some development measures at last.
Dynamic Simulation and Influencing Factors Analysis of Biofouling
Authors: Wang Da Cheng , Qian Cai Fu , Cao Sheng Xian , Liu Yang , Sun Jia Wei
Published: August 2013

The formation of fouling in stainless steel tube was simulated in the existence of both sulfate-reducing bacteria and iron bacteria under the experimental conditions of the water temperature 30±0.2°C and velocity of 0.4m/s with the dynamic simulation apparatus of shell-and-tube circulating cooling water. The paper studied the relation between water quality parameters and formation of fouling, such as Fe2+ concentration, CODcr and the total number of bacteria. The experimental results showed that: the main reason of the fouling resistance increase was the presence of sulfate-reducing bacteria and iron bacteria. The interaction between iron bacteria and sulfate-reducing bacteria accelerated the formation of biofouling. The influence of each parameter codetermined the formation of microbial fouling.
The Technical Modification and Performance Analysis of Diesel/LNG Dual Fuel Engines
Authors: Meng Chao , Si Jing Ping , Liang Ge Xi , Niu Jia Hua
Published: August 2013

As the global shortage of oil resource and the rapid increase in car ownership, using gas as the alternative fuel is getting more and more important. Gas fuel, such as LNG (liquefied natural gas), with resource-rich, less pollution and other features, is desirable alternative fuels for cars. In this article, through the engine bench test, a comparative analysis of power performance, fuel economy, emission between diesel/LNG dual engine and diesel engine was done. The result shows that, compared to the original machine , power performance of modified diesel / LNG dual fuel engine decline but isnt obvious. At the same time , fuel economy has a substantial increase. The use of natural gas can relieve shortage of global oil resource and the supply-demand imbalance of oil products. The emission of modified diesel / LNG dual fuel engine has a better state than that of original machines. This kind of modified dual fuel engine is simple, low cost, easily promoted and will be well utilized in future.
Analysis on Harmonics Caused by Connecting Electric Vehicle Chargers with Power Network
Authors: Li Xiang Zhen , Hu Guang Ming , Hou Peng Xin , Fan Yu Bo , Guo Chun Lin
Published: August 2013

As a class of nonlinear loads in the power system, electric vehicle chargers will produce a certain harmonic pollution for the grid. Before the construction of charging stations, it is necessary for electric vehicle charger (station) connected to the grid to simulate and predict harmonics. The models of single charger and charge station are built separately in order to simulate and analysis the impact of a single and multiple chargers on power quality. The factors of the harmonic current ratio (HRI) and the current total harmonic distortion (THDI) varied with the charging power and the number of the chargers are discussed and analyzed. The generation mechanism of harmonic counteraction and interaction between the chargers are analyzed. The simulation results show that: because of the impedance of the system and the transformer, the harmonic current ratio (HRI) and the current total harmonic distortion (THDI) both increase firstly to some extent and subsequently decrease gently with the increase of the number of the chargers in the same power charging. This phenomenon has nothing to do with the harmonic counteraction and how that happen is discussed and analysis in this paper. And the phenomenon of harmonics interaction and counteraction occurs with the increase of the number of the chargers in different power charging, and the current total harmonic distortion (THDI) declines and tends to maintain a relatively stable value.
Control Strategies for AC Motor of Electric Vehicles
Authors: Wang Da Fang , Hu Zhen Fei , Li Na , Jin Yi , Yang Bo Wen
Published: August 2013

Electric Vehicles (EVs) have been the important tendency of future vehicle development. This paper discusses the performance and features of EVs with AC drive system, and analyzes two dominating control schemes of AC motor dynamic model, i.e., Vector Control (VC) and Direct Torque Control (DTC). Principles, advantages, disadvantages, research hot spots and developing directions of the two control schemes were carefully presented. Moreover, the paper points out that the two difficulties of AC drive system are improving low-speed performance and dynamic performance.
Effect of Ignition Timing on the Starting Characteristics for Linear Engine
Authors: Li Hui Cong , Wang Zhe , Yin Zhao Lei , Zhang Tong
Published: August 2013

A starting experiment has been conducted to investigate the effect of ignition timing on the starting characteristics for linear engine designed by the research group independently. The fuel injection pulse and ignition timing are controlled by the electronic control unit (ECU) which is developed based on the piston displacement. The combustion characteristics of the engine in starting process are studied based on the cylinder pressure measured by the transient pressure sensor. The result shows that the best ignition timing for linear engine starting is 2.4mm~2.8mm when the fuel injection pulse is 5.4ms and this best region of ignition timing is also meet the requirement of the combustion in the next several cycles.
Thermal Analysis of the Battery Box in Electric Vehicles
Authors: Fan Wei , Wu Wei Jing , Chen Yan Hong , Shen Shuai , Li Ce Yuan
Published: August 2013

Based on the analysis of heat mechanism of the lithium-ion battery, the thermal properties on specific heat capacity and thermal conductivity were obtained by experiment , and then established thermal model of the monomer battery. Moreover, to verify the correctness of the model and get temperature field distribution, the heat simulation of it by using ANSYS Fluent software was conducted, After that, the monomer battery was grouped into five, then the simulation analysis of the grouped battery was done on the case of natural convection and forced convection. Finally, we verified the validity of the simulation by experiment.
Coarse Aggregate Gradation Design Index and Method of Asphalt Mixture
Authors: Zhang Ye Mao , Zheng Mu Lian , Hu Guang Wei , Zhu Qi Yang
Published: August 2013

The gradation of asphalt mixture is a main factor on the asphalt pavement performance, and coarse aggregate skeleton is an effect of distribution in the primary factor. The article analyses the interaction among the particle sizes of coarse aggregate by VCA and CBR double controlling index of aggregate gradually filling test, and identifies the key sizes of coarse aggregate by uniform design and grey system theory, and recommends particles size range content of coarse aggregate. The results show that coarse aggregate skeleton gradation of asphalt mixture by filling test has a good correlation with VCA and CBR.
Concrete Exterior Wall Insulation without Network System
Authors: Wei Shu Hua , Wang Xiao Jun
Published: August 2013

External thermal insulation system of Cast-in-situ concrete exterior wall in high-rise civil building includes with network and without network system, wherein the cast-in-place concrete exterior wall insulation without network system is the most economical and the external thermal insulation system. This system applies to new buildings, can also be applied to energy saving renovation of existing buildings. In this paper, the system technology without steelmesh is synthetically introduced so that more engineers can know and use it better.
Numerical Analysis on Hollow EPSRC Block and its Thermal Insulation Wall
Authors: Fan Xiao Sen , Chen Yan Li , Niu Xiao Ling , Wang Xian Cong , Liang Chao Feng
Published: August 2013

A new building material named expanded polystyrene recycled concrete (EPSRC) has been experimental studied not long ago by authors in this paper. Now, numerical analysis was further carried out on hollow EPSRC block and its thermal insulation wall based on thermodynamic principles. The results showed that the average thermal resistance of E45 and E60 EPSRC blocks are 0.616 and 0.823 (m2·K)/W, and the average heat transfer coefficient of E45 and E60 EPCRC masonry wall are 1.473 and 1.280 W/(m2·k). Therefore, the EPSRC blocks can be widely applied to the non load-bearing lightweight insulation masonry by suitable design.
Simulation of the Indoor Thermal Environment of Sunspaces-Attaching Passive Solar House in Shihezi of Xinjiang
Authors: Dong Li Qi , Jiang Shu Guang
Published: August 2013

Selecting sunspaces-attaching passive solar house and contrast house which have the same layout and enclosure structure, with the software of DEST to build model and simulation, obtained a heating period interior hourly temperature of the two houses. Arranging, calculating the white, day average indoor temperature of solar house and contrast house. The results show that sunspaces-attaching passive solar house can improve the indoor temperature 3°C, energy saving rate is 37% in this area.
Exergetic Analysis of a Solar Thermal Power Plant
Authors: Wu Jing Qiu , Zhu Dao Fei , Wang Hua , Zhu Yong
Published: August 2013

The study of heat loss and exergy loss distribution in the power plant system plays a very important role in improving the efficiency of the system. In this paper, a dynamic simulation model of the 5MW solar thermal power system is established. Then, the simulation test with the actual data in a solar thermal power plant is carried out, and we analyze the heat and the exergy loss of the system. The results show that, the heat loss of the condenser is the largest, up to 72%. To increase the thermal efficiency of the system, the energy-saving research for the condenser should be pay attention to. The solar collector field has the most of exergy loss in the system, accounting for approximately 89%. From the exergy efficiency perspective, the solar collector system has huge potential for energy- saving. The thermal efficiency and exergy efficiency of a solar thermal power plant system increases as the load increases, full-load operation of the unit should be maintained as much as possible.
A Review of the Application of LCA for Sustainable Buildings in Asia
Authors: Abd Rashid Ahmad Faiz , Yusoff Sumiani , Mahat Noorsaidi
Published: August 2013

The introduction of life cycle assessment (LCA) to the building industry is important due to its ability to systematically quantify every environmental impact involved in every process from cradle to grave. Within the last two decades, research on LCA has increased considerably covering from manufacturing of building materials and construction processes. However, the LCA application for buildings in Asia are limited and fragmented due to different research objectives, type of buildings and locations. This paper has attempted to collect and review the application of LCA in the building industry in Asia from the selected publications over the last 12 years, from 2001 to 2012. The result shows that most LCA research basic methodology is based on International Organization of Standardization (ISO) 14040 series but with variance. It is found that the operational phase consume highest energy and concrete responsible for the highest total embodied energy and environmental impact. It also suggested that building material with low initial embodied energy does not necessarily have low life cycle energy. Overall, findings from LCA studies can help to make informed decisions in terms of environmental impact and help realizing sustainable buildings in the future.
Analysis on Light Brick Research and the Application in China
Authors: Jin Dong Yan , Wu Xiao Gang
Published: August 2013

This paper demonstrated on a new specific light brick work folw on the basis of analysis of the technical performance, the economic index and the market perspective, puts forward the technical path for China's development of light brick industry.
Study on the Green Building Evaluation Standard
Authors: Zhang Jian , Jiao Li Jun , Li Su Zhen
Published: August 2013

In recent years, green buildings have been paid more and more attention. However, in the application, China's green building evaluation criteria still has some flaws. The paper aims at giving a summary of the definition and properties of green building. It is to analyze the characteristics of the current situation of the green building rating standards in our country and in view of our countrys bottlenecks and difficulties in the field of applicability at present, a countermeasure analysis will be made and relevant solutions put forward.
Study on the Seismic Performance of Cavity Walls Constraint Masonry Construction
Authors: Zuo Shu Hong , Bai Hong Lu , Xiong Li Hong , Liu Ben Yi , Tian Zhi Min
Published: August 2013

Cavity walls structure is unsuitable in cold area for its faultiness of poor heat-insulating property. But the cavity walls constraint masonry construction is suitable in cold area for its high heat-insulating property. Studies are carried as setting up the restoring force model of the cavity walls confined masonry structure and analyzing the dynamic time-history of cavity walls constraint masonry structure under 7 degrees small earthquake, middle earthquake or large earthquake through EL centro wave, TALF wave, Ninghe wave and Qian'an wave, which indicates that cavity walls constraint masonry construction can satisfy seismic demand of 7 degree quake. Finally, the formula for calculating the interlayer displacement of cavity walls confined masonry structure near collapse is put forward and the counting result is compared with that of dynamic time-history analyzing, which shows that the accuracy of this formula is high enough to be used for analyzing the seismic performance of cavity walls constraint masonry structure.
Foundation projects: Special Basic Scientific Research for Central Public Institute (2008B002, 2010A04), Open Fund of Key Laboratory of State Education Ministroy on Urben and Engineering Safe and Disaster Diminish & Key Laboratory of Beijing on Engineering Seismic and Treatment (EESR2010-07), and High Level Talent Support Project of Heilongjiang University (HDTD2010-13).
Key Technologies Research of New Generation Concentrating Photovoltaic
Authors: Liu Chun Tong , Bing Li , Tao Wang , Li Hong Cai
Published: August 2013

The new concentrating photovoltaic (CPV) with core technology of III-V multi-junction cells, can significantly reduce the cost of photovoltaic system, and with advantages of high conversion rate, light weight, small size, energy saving and environmental protection, etc, which was widely regarded as the next-generation of solar photovoltaic technology. On the basis of the introduction of related research process, the paper concentrating discuss on the key technologies such as the new efficient multi-junction cells, high performance non-imaging concentrated light technology and sun tracking system, and propose the appropriate technical solutions, which can provide reference for the application and dissemination of the new generation concentrating photovoltaic.
Study on the Effect of Grid Beam on Seismic Performance of Improved Multi-Ribbed Slab Structure
Authors: Qian Kun , Dong Gui Yan , Zhang Jie , Yuan Quan
Published: August 2013

In order to confirm the calculation model of multi-ribbed slab structure and transmission of earthquake action, this paper improved the existing multi-ribbed slab structure. The calculation model of improved multi-ribbed slab structure confirmed the stress relationship among three seismic fortification lines, and the transmission of earthquake action became clear, this calculation model could be applied in structural analysis. For studying the effect of characteristic parameters of restoring force changing in the second seismic fortification line on seismic performance, and correcting the parameters of grid beam, this paper analyzed push-over model of the second seismic fortification line to get the static pushover curve. According to the study, the amount of steel bar in grid beam and sectional dimension of grid beam made the major effect on characteristic parameters of restoring force in the second seismic fortification line, concrete grade of grid beam is a unconsidered factor. Nominal elastic modulus of filling materials didnt much affect the yield strength and yield displacement of the second seismic fortification line, but made significant effect on post-yield strength.
Preparation and Optical Properties of Gallium-Titanium Codoped Zinc Oxide Transparent Conductive Films for Solar Cells
Authors: Zhang T. , Wang H. , Zhong Z.Y. , Yang C.Y. , Hou Jin
Published: August 2013

Transparent conducting gallium-titanium codoped zinc oxide thin films were grown onto glass substrates with magnetron sputtering technique in ambient argon gas, and the influence of argon pressure on optical properties of the films were investigated. The refractive indexes of the films were calculated. It is found that the refractive index tends to increase with increasing the photon energy. Meanwhile, the dispersion behavior of the refractive index was analyzed in terms of the single-oscillator model and the oscillator parameters were obtained. Furthermore, the optical energy gaps were evaluated by single-oscillator model and Tauc’s relation, respectively. The values of optical energy gap estimated from single-oscillator model are in agreement with those determined from Tauc’s relation.
Acid-Alkaline Two-Stage Pretreatments of Corn Stover for Enhancing Enzymatic Saccharification
Authors: Wang Hai Song , Gao Hong Ling , Li Bin , Mu Xin Dong
Published: August 2013

For the enzymatic saccharification of lignocellulosic biomass, single acid or alkaline pretreatment is not satisfactory because of the low sugar yields together with the neutralization of residual chemicals before enzymatic hydrolysis. Herein, an acid-alkaline two-stage pretreatment process was designed to treat corn stover. During the process, the pretreated liquid from the first stage and the solid residues from the second stage were mixed together for the subsequent simultaneous enzymatic hydrolysis, where a mixture of cellulase with an activity loading of 20 FPU/g substrate, cellobiase with an activity loading of 5 U/g substrate, and xylanase with an activity loading of 200 U/g substrate was used. Compared to the single acid or alkaline pretreatment, the acid-alkaline two-stage pretreatment could significantly improve the enzymatic saccharification, and 91.2% glucose yield with 52.56% of the theoretical total reducing sugar yield was achieved after the subsequent enzymatic hydrolysis.