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Implementation and performance evaluation of advance metering infrastructure for Borneo-Wide Power Grid

Mujahid TABASSUM,Manas K. HALDAR,Duaa Fatima S. KHAN

《能源前沿(英文)》 2020年 第14卷 第1期   页码 192-211 doi: 10.1007/s11708-016-0438-2

摘要: In this paper, a supervisory computer network for Borneo-Wide Power Grid system have been proposed and implemented, which includes a renewable power generation and advanced metering infrastructure. An Internet-based communication network running on multiprotocol label switching (MPLS) has been implemented for a smart power grid, with the addition of the renewable energy monitoring system. The centralized supervisory control and data acquisition systems (SCADA) are replaced by a wide area monitoring system(WAMS) comprising of a phasor measurement unit (PMU). The implemented communication network used advanced metering infrastructure that operates on worldwide interoperability for microwave access (WiMAX), wireless fidelity (Wi-Fi) and low power Wi-Fi, which are proposed for the distribution systems of Sarawak Energy. The proposed wide area network (WAN) is simulated using OPNET Modeler and the results are compared with the existing WAN used by Sarawak Energy.

关键词: renewable energy     multiprotocol label switching (MPLS)     power grid     phasor measurement unit (PMU)     supervisory control and data acquisition systems (SCADA)     wide area monitoring system (WAMS)     worldwide interoperability for microwave access (WiMAX)     synchronous digital hierarchy (SDH)    

<bold>Chemical poison and regeneration of SCR catalysts for NObold><bold>xbold><bold> removal from stationary sourcesbold>

Junhua LI,Yue PENG,Huazhen CHANG,Xiang LI,John C. CRITTENDEN,Jiming HAO

《环境科学与工程前沿(英文)》 2016年 第10卷 第3期   页码 413-427 doi: 10.1007/s11783-016-0832-3

摘要: Selective catalytic reduction (SCR) of NO with NH is an effective technique to remove NO from stationary sources, such as coal-fired power plant and industrial boilers. Some of elements in the fly ash deactivate the catalyst due to strong chemisorptions on the active sites. The poisons may act by simply blocking active sites or alter the adsorption behaviors of reactants and products by an electronic interaction. This review is mainly focused on the chemical poisoning on V O -based catalysts, environmental-benign catalysts and low temperature catalysts. Several common poisons including alkali/alkaline earth metals, SO and heavy metals etc. are referred and their poisoning mechanisms on catalysts are discussed. The regeneration methods of poisoned catalysts and the development of poison-resistance catalysts are also compared and analyzed. Finally, future research directions in developing poisoning resistance catalysts and facile efficient regeneration methods for SCR catalysts are proposed.

关键词: flue gas     DeNOx     SCR catalyst     poison and regeneration    

<bold>Enhanced disinfection of bold><bold>Escherichia colibold> <bold>and bacteriophageMS2 in water using a copper and silver loaded titanium dioxide nanowire membranebold>

Guiying RAO, Kristen S. BRASTAD, Qianyi ZHANG, Rebecca ROBINSON, Zhen HE, Ying LI

《环境科学与工程前沿(英文)》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0854-x

摘要: A novel photocatalytic Ag-Cu-TiO nanowire membrane was fabricated. Bacteria and virus disinfection was improved by co-depositing Ag and Cu onto membrane. Synergetic photocatalytic effects and free metal ions of Ag and Cu contribute to disinfection. 7.68 log removal of and 4.02 log removal of bacteriophage MS2 were achieved. Titanium dioxide (TiO ) is a widely used photocatalyst that has been demonstrated for microorganism disinfection in drinking water. In this study, a new material with a novel structure, silver and copper loaded TiO nanowire membrane (Cu-Ag-TiO ) was prepared and evaluated for its efficiency to inactivate and bacteriophage MS2. Enhanced photo-activated bactericidal and virucidal activities were obtained by the Cu-Ag-TiO membrane than by the TiO , Ag-TiO and Cu-TiO membranes under both dark and UV light illumination. The better performance was attributed to the synergies of enhanced membrane photoactivity by loading silver and copper on the membrane and the synergistic effect between the free silver and copper ions in water. At the end of a 30 min test of dead-end filtration under 254 nm UV irradiation, the Cu-Ag-TiO membrane was able to obtain an removal of 7.68 log and bacteriophage MS2 removal of 4.02 log, which have met the US EPA standard. The free metal ions coming off the membrane have concentrations of less than 10 ppb in the water effluent, far below the US EPA maximum contaminant level for silver and copper ions in drinking water. Therefore, the photo-activated disinfection by the Cu-Ag-TiO membrane is a viable technique for meeting drinking water treatment standards of microbiological water purifiers.

关键词: Photo-activated disinfection     Titanium dioxide     Nanowire membrane     Silver     Copper    

Adsorption of humic acid from aqueous solution on bilayer hexadecyltrimethyl ammonium bromide-modified zeolite

Yanhui ZHAN, Jianwei LIN, Yanling QIU, Naiyun GAO, Zhiliang ZHU

《环境科学与工程前沿(英文)》 2011年 第5卷 第1期   页码 65-75 doi: 10.1007/s11783-010-0277-z

摘要: Surfactant-modified natural zeolites (SMNZ) with different coverage types were prepared by loading hexadecyltrimethyl ammonium bromide (HTAB) onto the surface of a natural zeolite. The adsorption behavior of humic acid (HA) on SMNZ was investigated. Results indicate that the adsorbent SMNZ exhibited a higher affinity toward HA than the natural zeolite. HA removal efficiency by SMNZ increased with HTAB loading. Coexisting Ca in solution favored HA adsorption onto SMNZ. Adsorption capacity decreased with an increasing solution pH. For typical SMNZ with bilayer HTAB coverage, HA adsorption process is well described by a pseudo-second-order kinetic model. The experimental isotherm data fitted well with the Langmuir model. Calculated maximum HA adsorption capacities for SMNZ with bilayer HTAB coverage at pH 5.5 and 7.5 were 63 and 41 mg·g , respectively. E2/E3 (absorbance at 250 nm to that at 365 nm) and E4/E6 (absorbance at 465 nm to that at 665 nm) ratios of the residual HA in solution were lower than that of the original HA solution. This indicates that the HA fractions with high polar functional groups, low molecular weight (MW), and aromaticity had a stronger tendency for adsorption onto SMNZ with bilayer HTAB coverage. Results show that HTAB-modified natural zeolite is a promising adsorbent for removal of HA from aqueous solution.

关键词: bilayer surfactant-modified zeolite     hexadecyltrimethyl ammonium bromide (HTAB)     adsorption     humic acid (HA)    

无轴承永磁同步电机转子磁场定向控制系统研究

朱熀秋,巫亮,周阳,张腾超,邓建明

《中国工程科学》 2006年 第8卷 第6期   页码 35-40

摘要:

无轴承永磁同步电机是具有磁悬浮轴承优点的一种新型电机;在阐述了无轴承永磁同步电机工作原理基础上,采用转子磁场定向控制策略,推导了无轴承永磁同步电机径向悬浮力和电机旋转部分数学模型;根据无轴承电机解耦控制的要求设计了无轴承永磁同步电机转子磁场定向矢量控制系统,并以数字信号处理器TMS320LF2407为核心,研制了矢量控制系统的硬件和软件。实验结果表明:电机工作在0~3000r/min范围内,转子悬浮稳定且电机转速连续可调。

关键词: 无轴承永磁同步电机     解耦控制     数字信号处理器     数字控制    

Study on affecting factors of collaborative product development based on collaboration hierarchy model

ZHANG Xiaodong, LI Yingzi, ZHANG Zhiqiang

《机械工程前沿(英文)》 2007年 第2卷 第2期   页码 210-213 doi: 10.1007/s11465-007-0036-4

摘要: Aiming at the levels of collaborative degree in web-based product development, a collaboration hierarchy model of this product development is developed in this paper. Based on the model, the affecting factors on collaboration levels are analyzed systematically from many aspects, such as technology, organization and business. A gap analysis method is studied in detail, and is applied in a real project. The application shows that it can solve the diverse problems of collaborative product development effectively, and help enterprises find out the critical factors that affect the collaboration.

关键词: development     web-based     business     collaborative     collaboration hierarchy    

Practical evaluation for water utilities in China by using analytic hierarchy process

Hong CHEN,Feng XIAO,Zhe BI,Ping XIAO,Dongsheng WANG,Ming YANG

《环境科学与工程前沿(英文)》 2015年 第9卷 第1期   页码 131-137 doi: 10.1007/s11783-014-0718-1

摘要: The risk of water utilities would include the water quality failure and the water quantity failure, from the source to the tap, including the catchment, treatment, distribution and the customer plumbing system. In this paper, we proposed a practical evaluation method based on the analytic hierarchy process (AHP). The hierarchical structure of the water utilities was established in terms of the fault event analysis from the past failure accidents. The severity of criteria was preset by the experts and the probability of criteria was determined by a modified CUWA-TSM sheet with the consideration of the actual situations of the supply system. The evaluation model was successfully performed by a case study. Although, the method in this paper may not be as good as the framework of WSPs, it has a great advantage compared to WSPs and TSM. The risk management can be applied through specific software packages with a user-friendly interface, which means it is easier to implement. In addition, it can point out the critical control points (CCPs) for the decision-makers. So we believe this method will improve and play a more and more active role in the development of the risk management in China water works.

关键词: analytic hierarchy process (AHP)     risk management     water quality failure     water quantity failure    

enthalpy of formation for polycyclic aromatic hydrocarbons predicting from general connectivity based hierarchy

《化学科学与工程前沿(英文)》 2022年 第16卷 第12期   页码 1743-1750 doi: 10.1007/s11705-022-2184-9

摘要: The standard enthalpy of formation is an important predictor of the reaction heat of a chemical reaction. In this work, a high-precision method was developed to calculate accurate standard enthalpies of formation for polycyclic aromatic hydrocarbons based on the general connectivity based hierarchy (CBH) with the discrete correction of atomization energy. Through a comparison with available experimental findings and other high-precision computational results, it was found that the present method can give a good description of enthalpy of formation for polycyclic aromatic hydrocarbons. Since CBH schemes can broaden the scope of application, this method can be used to investigate the energetic properties of larger polycyclic aromatic hydrocarbons to achieve a high-precision calculation at the CCSD(T)/CBS level. In addition, the energetic properties of CBH fragments can be accurately calculated and integrated into a database for future use, which will increase computational efficiency. We hope this work can give new insights into the energetic properties of larger systems.

关键词: standard enthalpy of formation     polycyclic aromatic hydrocarbons     connectivity based hierarchy     high-precision calculation    

Influencing factors and control measures of excavation on adjacent bridge foundation based on analytic hierarchy

Shuangxi FENG, Huayang LEI, Yongfeng WAN, Haiyan JIN, Jun HAN

《结构与土木工程前沿(英文)》 2021年 第15卷 第2期   页码 461-477 doi: 10.1007/s11709-021-0705-0

摘要: Many uncertain factors in the excavation process may lead to excessive lateral displacement or over-limited internal force of the piles, as well as inordinate settlement of soil surrounding the existing bridge foundation. Safety control is pivotal to ensuring the safety of adjacent structures. In this paper, an innovative method is proposed that combines an analytic hierarchy process (AHP) with a finite element method (FEM) to reveal the potential impact risk of uncertain factors on the surrounding environment. The AHP was adopted to determine key influencing factors based on the weight of each influencing factor. The FEM was used to quantify the impact of the key influencing factors on the surrounding environment. In terms of the AHP, the index system of uncertain factors was established based on an engineering investigation. A matrix comparing the lower index layer to the upper index layer, and the weight of each influencing factor, were calculated. It was found that the excavation depth and the distance between the foundation pit and the bridge foundation were fundamental factors. For the FEM, the FE baseline model was calibrated based on the case of no bridge surrounding the foundation pit. The consistency between the monitoring data and the numerical simulation data for a ground settlement was analyzed. FE simulations were then conducted to quantitatively analyze the degree of influence of the key influencing factors on the bridge foundation. Furthermore, the lateral displacement of the bridge pile foundation, the internal force of the piles, and the settlement of the soil surrounding the pile foundation were emphatically analyzed. The most hazardous construction condition was also determined. Finally, two safety control measures for increasing the numbers of support levels and the rooted depths of the enclosure structure were suggested. A novel method for combining AHP with FEM can be used to determine the key influencing aspects among many uncertain factors during a construction, which can provide some beneficial references for engineering design and construction.

关键词: deep foundation pit excavation     adjacent bridge foundation     influencing factors     analytic hierarchy process     finite element    

Hierarchical methodological framework to improve Policy Environmental Assessment: Based on policy layer research

Yinglie ZHOU, Cunkuan BAO,

《环境科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 82-90 doi: 10.1007/s11783-010-0004-9

摘要: This study explores the current implementation challenges of the Policy Environmental Assessment (PEA), including the implementation of a far richer, more diverse (at macro level), and better understanding of PEA and integration with decision making. The results contribute to the analysis of PEA through different hierarchies of assessment. Stemming from the theory and practice of policy, a concept of PEA hierarchies is proposed including the uppermost PEA, upper-lower PEA, and lowermost PEA. Afterward, the differences of the three hierarchies are interpreted, in terms of aims, principles, processes, and methods. The evaluation of the policy environmental impacts from different lens helps solve the complexities of policies and identify opportunities for improvement of PEA.

关键词: Policy Environmental Assessment (PEA)     policy hierarchy     PEA hierarchy     methodological framework    

Modeling and control of a permanent magnet synchronous generator dedicated to standalone wind energy

Louar FATEH,Ouari AHMED,Omeiri AMAR,Djellad ABDELHAK,Bouras LAKHDAR

《能源前沿(英文)》 2016年 第10卷 第2期   页码 155-163 doi: 10.1007/s11708-016-0410-1

摘要: The interest for the use of renewable energies has increased, because of the increasing concerns of the environmental problems. Among renewable energies, wind energy is now widely used. Wind turbines based on an asynchronous generator with a wound rotor present the inconvenience of requiring a system of rings and brooms and a multiplier, inferring significant costs of maintenance. To limit these inconveniences, certain manufacturers developed wind turbines based on synchronous machines with large number of pairs of poles coupled directly with the turbine, avoiding using the multiplier. If the generator is equipped with permanent magnets, the system of rings and brooms is eliminated. The control of the permanent magnet synchronous generator (PMSG) can be affected with the implementation of various techniques of control. This paper presented a new approach mainly based on the control strategy of power production system based on the PMSG. In fact, a mathematical model that simulates the Matlab chain was established with the introduction of control techniques, such as direct control of the torque (DTC) to control the load side converter (LSC), the control of the speed of the turbine and the DC-bus voltage ensured by PI regulators. To show the performance of the correctors used, some simulation results of the system were presented and analyzed.

关键词: wind turbine     permanent magnet synchronous generator (PMSG)     converter     proportional-integral (PI)     control     direct control of the torque (DTC)     regulation    

基于同步波动原理的抗冲蚀弹性涂层设计

郭源君,肖华林,徐大清,李文斌

《中国工程科学》 2008年 第10卷 第9期   页码 60-63

摘要:

基于过流面冲蚀波纹形貌特征与流体边界层扰动波参数的对应关系,提出了实现弹性涂层边壁与边界层扰动波的同步波动,从而变边壁被动承受粒子冲击为主动回避与粒子的碰撞的抗冲蚀设计思想;分析了实现弹性涂层边壁与边界层扰动波同步波动的条件,并由此确定出弹性涂层的材料常数。

关键词: 冲蚀     边界层     弹性边壁     弹性涂层     同步波动    

Application of fuzzy analytic hierarchy process model on determination of optimized pile-type

Lei MA, Shuilong SHEN, Jinhui ZHANG, Yang HUANG, Feng SHI

《结构与土木工程前沿(英文)》 2010年 第4卷 第2期   页码 252-257 doi: 10.1007/s11709-010-0017-2

摘要: Pile-type selection is a very important stage of foundation design, and there are many field factors influencing the decision of pile-type selection. Since there is a limitation of traditional “major factors method” to satisfy the requirement of modern foundation construction, this study presents an efficient approach, in which analytic hierarchy process (AHP) is employed. AHP is a multiple criteria decision-making tool that has been applied in many fields related to the decision-making, e.g., in the field of economics, marketing, sociology, etc. However, it is rarely reported that AHP is applied in the field of civil engineering for decision making. In this study, AHP combined with fuzzy synthetic evaluation method is employed to select the type of pile used as the foundation of a residential building in Fuzhou, Fujian Province, China. The results show that fuzzy AHP approach is an easy and efficient way for pile-type selection.

关键词: pile type     fuzzy synthetic evaluation     analytic hierarchy process (AHP)     optimal selection    

Equivalent circuit and characteristic simulation of a brushless electrically excited synchronous wind

Hao WANG, Fengge ZHANG, Tao GUAN, Siyang YU

《机械工程前沿(英文)》 2017年 第12卷 第3期   页码 420-426 doi: 10.1007/s11465-017-0439-9

摘要:

A brushless electrically excited synchronous generator (BEESG) with a hybrid rotor is a novel electrically excited synchronous generator. The BEESG proposed in this paper is composed of a conventional stator with two different sets of windings with different pole numbers, and a hybrid rotor with powerful coupling capacity. The pole number of the rotor is different from those of the stator windings. Thus, an analysis method different from that applied to conventional generators should be applied to the BEESG. In view of this problem, the equivalent circuit and electromagnetic torque expression of the BEESG are derived on the basis of electromagnetic relation of the proposed generator. The generator is simulated and tested experimentally using the established equivalent circuit model. The experimental and simulation data are then analyzed and compared. Results show the validity of the equivalent circuit model.

关键词: wind power     brushless electrically excited synchronous generator     hybrid rotor     equivalent circuit    

Robust nonlinear control via feedback linearization and Lyapunov theory for permanent magnet synchronous

Ridha CHEIKH, Arezki MENACER, L. CHRIFI-ALAOUI, Said DRID

《能源前沿(英文)》 2020年 第14卷 第1期   页码 180-191 doi: 10.1007/s11708-018-0537-3

摘要: In this paper, the method for the nonlinear control design of a permanent magnet synchronous generator based-wind energy conversion system (WECS) is proposed in order to obtain robustness against disturbances and harvest a maximum power from a typical stochastic wind environment. The technique overcomes both the problem of nonlinearity and the uncertainty of the parameter compared to such classical control designs based on traditional control techniques. The method is based on the differential geometric feedback linearization technique (DGT) and the Lyapunov theory. The results obtained show the effectiveness and performance of the proposed approach.

关键词: permanent magnet synchronous generator     wind energy conversion system     stochastic     differential geometric     feedback linearization     maximum power point tracking     Lyapunov     robust control    

标题 作者 时间 类型 操作

Implementation and performance evaluation of advance metering infrastructure for Borneo-Wide Power Grid

Mujahid TABASSUM,Manas K. HALDAR,Duaa Fatima S. KHAN

期刊论文

<bold>Chemical poison and regeneration of SCR catalysts for NObold><bold>xbold><bold> removal from stationary sourcesbold>

Junhua LI,Yue PENG,Huazhen CHANG,Xiang LI,John C. CRITTENDEN,Jiming HAO

期刊论文

<bold>Enhanced disinfection of bold><bold>Escherichia colibold> <bold>and bacteriophageMS2 in water using a copper and silver loaded titanium dioxide nanowire membranebold>

Guiying RAO, Kristen S. BRASTAD, Qianyi ZHANG, Rebecca ROBINSON, Zhen HE, Ying LI

期刊论文

Adsorption of humic acid from aqueous solution on bilayer hexadecyltrimethyl ammonium bromide-modified zeolite

Yanhui ZHAN, Jianwei LIN, Yanling QIU, Naiyun GAO, Zhiliang ZHU

期刊论文

无轴承永磁同步电机转子磁场定向控制系统研究

朱熀秋,巫亮,周阳,张腾超,邓建明

期刊论文

Study on affecting factors of collaborative product development based on collaboration hierarchy model

ZHANG Xiaodong, LI Yingzi, ZHANG Zhiqiang

期刊论文

Practical evaluation for water utilities in China by using analytic hierarchy process

Hong CHEN,Feng XIAO,Zhe BI,Ping XIAO,Dongsheng WANG,Ming YANG

期刊论文

enthalpy of formation for polycyclic aromatic hydrocarbons predicting from general connectivity based hierarchy

期刊论文

Influencing factors and control measures of excavation on adjacent bridge foundation based on analytic hierarchy

Shuangxi FENG, Huayang LEI, Yongfeng WAN, Haiyan JIN, Jun HAN

期刊论文

Hierarchical methodological framework to improve Policy Environmental Assessment: Based on policy layer research

Yinglie ZHOU, Cunkuan BAO,

期刊论文

Modeling and control of a permanent magnet synchronous generator dedicated to standalone wind energy

Louar FATEH,Ouari AHMED,Omeiri AMAR,Djellad ABDELHAK,Bouras LAKHDAR

期刊论文

基于同步波动原理的抗冲蚀弹性涂层设计

郭源君,肖华林,徐大清,李文斌

期刊论文

Application of fuzzy analytic hierarchy process model on determination of optimized pile-type

Lei MA, Shuilong SHEN, Jinhui ZHANG, Yang HUANG, Feng SHI

期刊论文

Equivalent circuit and characteristic simulation of a brushless electrically excited synchronous wind

Hao WANG, Fengge ZHANG, Tao GUAN, Siyang YU

期刊论文

Robust nonlinear control via feedback linearization and Lyapunov theory for permanent magnet synchronous

Ridha CHEIKH, Arezki MENACER, L. CHRIFI-ALAOUI, Said DRID

期刊论文