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LARGE-SCALE FARMING BENEFITS SOIL ACIDIFICATION ALLEVIATION THROUGH IMPROVED FIELD MANAGEMENT IN BANANA

《农业科学与工程前沿（英文）》 2023年 第10卷 第1期   页码 48-60 doi: 10.15302/J-FASE-2022475

摘要：

● Large farms had the highest average yield and the least yield variation.

关键词： plantations     land transfer     large-scale farming     nutrient management     soil acidification    

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Cluster voltage control method for “Whole County” distributed photovoltaics based on improved differential

《能源前沿（英文）》   页码 782-795 doi: 10.1007/s11708-023-0905-8

摘要： China is vigorously promoting the “whole county promotion” of distributed photovoltaics (DPVs). However, the high penetration rate of DPVs has brought problems such as voltage violation and power quality degradation to the distribution network, seriously affecting the safety and reliability of the power system. The traditional centralized control method of the distribution network has the problem of low efficiency, which is not practical enough in engineering practice. To address the problems, this paper proposes a cluster voltage control method for distributed photovoltaic grid-connected distribution network. First, it partitions the distribution network into clusters, and different clusters exchange terminal voltage information through a “virtual slack bus.” Then, in each cluster, based on the control strategy of “reactive power compensation first, active power curtailment later,” it employs an improved differential evolution (IDE) algorithm based on Cauchy disturbance to control the voltage. Simulation results in two different distribution systems show that the proposed method not only greatly improves the operational efficiency of the algorithm but also effectively controls the voltage of the distribution network, and maximizes the consumption capacity of DPVs based on qualified voltage.

关键词： distributed photovoltaics (DPVs)     cluster partitioning     improved differential evolution algorithm     voltage control     consumption capacity of distributed photovoltaics    

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Manufacturing system modeling and performance evaluation based on improved stochastic statechart

ZHANG Guojun, HE Jiabing, ZHU Haiping, CHEN Xuan

《机械工程前沿（英文）》 2007年 第2卷 第4期   页码 453-458 doi: 10.1007/s11465-007-0078-7

摘要： Stochastic statecharts are widely used in modeling systems. Considering that the comparability between different subsystems can streamline the modeling process, a stochastic statechart is improved by using the abstract sub-system and general system chart to express the comparability and integrity of a stochastic statechart respectively. Per formance data can be obtained by using a continuous-time Markov chain, which is transformed from a manufacturing system model described by the improved stochastic statechart. The case study shows that the improved stochastic statechart can effectively simplify the modeling and performance evaluation process and the results are useful to the configuration and optimization of a manufacturing system.

关键词： performance evaluation     different     configuration     improved     continuous-time    

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Time of flight improved thermally grown oxide thickness measurement with terahertz spectroscopy

《机械工程前沿（英文）》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0705-3

摘要： As a nondestructive testing technique, terahertz time-domain spectroscopy technology is commonly used to measure the thickness of ceramic coat in thermal barrier coatings (TBCs). However, the invisibility of ceramic/thermally grown oxide (TGO) reflective wave leads to the measurement failure of natural growth TGO whose thickness is below 10 μm in TBCs. To detect and monitor TGO in the emergence stage, a time of flight (TOF) improved TGO thickness measurement method is proposed. A simulative investigation on propagation characteristics of terahertz shows the linear relationship between TGO thickness and phase shift of feature wave. The accurate TOF increment could be acquired from wavelet soft threshold and cross-correlation function with negative effect reduction of environmental noise and system oscillation. Thus, the TGO thickness could be obtained efficiently from the TOF increment of the monitor area with different heating times. The averaged error of 1.61 μm in experimental results demonstrates the highly accurate and robust measurement of the proposed method, making it attractive for condition monitoring and life prediction of TBCs.

关键词： thermal barrier coatings     thermally grown oxide     terahertz spectroscopy     time of flight    

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A method for predicting consolidation settlements of floating column improved clayey subsoil

Jinchun CHAI, Supasit PONGSIVASATHIT,

《结构与土木工程前沿（英文）》 2010年 第4卷 第2期   页码 241-251 doi: 10.1007/s11709-010-0024-3

摘要： A method of predicting the consolidation settlement-time curve of floating soil-cement column on improved soft clayey subsoil has been proposed. The degree of the consolidation (()) of the system is calculated by the double soil-layer consolidation theory, and the methods for evaluating the equivalent hydraulic conductivity () and the coefficient of volume compressibility () of the part of the column improved layer have been proposed. The effectiveness of the method was verified by comparing predictions with the results of finite element analysis (FEA) using a unit cell model. The consolidation settlement (()) can be calculated by the method of treating a part of the column improved layer as an unimproved layer and using the corresponding average () value. By comparing the predicted results with the measurements of laboratory model tests and three case histories in Fukuoka, Japan, the effectiveness of the proposed methods has been verified. It is suggested that the method can be used for designing the soft clayey subsoil improvement using floating soil-cement columns.

关键词： cement depth mixing     ground improvement     consolidation     settlement    

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Dynamic characteristics and improved MPPT control of PV generator

Houda BRAHMI, Rachid DHIFAOUI

《能源前沿（英文）》 2013年 第7卷 第3期   页码 342-350 doi: 10.1007/s11708-013-0242-1

摘要： This paper presents a mathematical model of photovoltaic (PV) module and gives a strategy to calculate online the maximum power point (MPP). The variation of series and shunt resistor are taken into account in the model and are dynamically identified using the Newton-Raphson algorithm. The effectiveness of the proposed model is verified by laboratory experiments obtained by implementing the model on the dSPACE DS1104 board.

关键词： modeling of photovoltaic (PV) generator     maximum power point tracking (MPPT)     estimation parameters     real time controller    

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operation of energy at hydrothermal power plants by simultaneous minimization of pollution and costs using improved

Homayoun EBRAHIMIAN,Bahman TAHERI,Nasser YOUSEFI

《能源前沿（英文）》 2015年 第9卷 第4期   页码 426-432 doi: 10.1007/s11708-015-0376-4

摘要： The aim of this paper is simultaneous minimization of hydrothermal units to reach the best solution by employing an improved artificial bee colony (ABC) algorithm in a multi-objective function consisting of economic dispatch (ED) considering the valve-point effect and pollution function in power systems in view of the hot water of the hydro system. In this type of optimization problem, all practical constraints of units were taken into account as much as possible in order to comply with the reality. These constraints include the maximum and minimum output power of units, the constraints caused by the balance between supply and demand, the impact of pollution, water balance, uneven production curve considering the valve-point effect and system losses. The proposed algorithm is applied on the studied system, and the obtained results indifferent operating conditions are analyzed. To investigate in various operating conditions, different load profiles in 12 h are taken into account. The obtained results are compared with those of the other methods including the genetic algorithm (GA), the Basu technique, and the improved genetic algorithm. Fast convergence is one of this improved algorithm features.

关键词： practical constraints of units     pollution function     inlet steam valve     up-ramp rate of units     improved ABC algorithm    

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Innovative hybrid reinforcement constituting conventional longitudinal steel and FRP stirrups for improved

Mostafa FAKHARIFAR,Ahmad DALVAND,Mohammad K. SHARBATDAR,Genda CHEN,Lesley SNEED

《结构与土木工程前沿（英文）》 2016年 第10卷 第1期   页码 44-62 doi: 10.1007/s11709-015-0295-9

摘要： The use of fiber reinforced polymer (FRP) reinforcement is becoming increasingly attractive in construction of new structures. However, the inherent linear elastic behavior of FRP materials up to rupture is considered as a major drawback under seismic attacks when significant material inelasticity is required to dissipate the input energy through hysteretic cycles. Besides, cost considerations, including FRP material and construction of pre-fabricated FRP configurations, especially for stirrups, and probable damage to epoxy coated fibers when transported to the field are noticeable issues. The current research has proposed a novel economical hybrid reinforcement scheme for the next generation of infrastructures implementing on-site fabricated FRP stirrups comprised of FRP sheets. The hybrid reinforcement consists of conventional longitudinal steel reinforcement and FRP stirrups. The key feature of the proposed hybrid reinforcement is the enhanced strength and ductility owing to the considerable confining pressure provided by the FRP stirrups to the longitudinal steel reinforcement and core concrete. Reinforced concrete beam specimens and beam-column joint specimens were tested implementing the proposed hybrid reinforcement. The proposed hybrid reinforcement, when compared with conventional steel stirrups, is found to have higher strength, stiffness, and energy dissipation. Design methods, structural behavior, and applicability of the proposed hybrid reinforcement are discussed in detail in this paper.

关键词： FRP     ductility     confinement     seismic     shear    

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SARS-CoV-2 vaccine research and immunization strategies for improved control of the COVID-19 pandemic

《医学前沿（英文）》 2022年 第16卷 第2期   页码 185-195 doi: 10.1007/s11684-021-0913-y

摘要： The record speed at which Chinese scientists identified severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and shared its genomic sequence with the world, has greatly facilitated the development of coronavirus disease (COVID-19) diagnostics, drugs, and vaccines. It is unprecedented in pandemic control history to develop a dozen successful vaccines in the first year and to immunize over half of the global population in the second year, due to the efforts of the scientific community, biopharmaceutical industry, and regulatory agencies worldwide. The challenges are both great and multidimensional due to the rapid emergence of virus variants and waning of vaccine immunity. Vaccination strategies need to adapt to these challenges to keep population immunity above the herd immunity threshold, by increasing vaccine coverage, especially for older adults and young people, and providing timely booster doses with homologous or heterologous vaccine boosts. Further research should be undertaken to develop more effective vaccines against SARS-CoV-2 variants and to understand the best prime-boost vaccine combinations and immunization strategies to provide sufficient and sustainable immune protection against COVID-19.

关键词： COVID-19     pandemics     SARS-CoV-2     vaccination    

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Design and synthesis of ZnCoO/CdS for substantially improved photocatalytic hydrogen production

《化学科学与工程前沿（英文）》 2023年 第17卷 第5期   页码 606-616 doi: 10.1007/s11705-022-2233-4

摘要： In this study, the hydrogen evolution performance of CdS nanorods is improved using ZnCo2O4. ZnCo2O4 nanospheres are synthesized using the hydrothermal and calcination methods, and CdS nanorods are synthesized using the solvothermal method. From the perspective of morphology, numerous CdS nanorods are anchored on the ZnCo2O4 microspheres. According to the experimental results of photocatalytic hydrogen evolution, the final hydrogen evolution capacity of 7417.5 μmol∙g–1∙h–1 is slightly more than two times that of the single CdS, which proves the feasibility of our study. Through various characterization methods, it is proved that the composite sample has suitable optoelectronic properties. In addition, ZnCo2O4 itself exhibits good conductivity and low impedance, which shortens the charge-transfer path. Overall, the introduction of ZnCo2O4 expands the adsorption range of light and improves the performance of photocatalytic hydrogen evolution. This design can provide reference for developing high-efficiency photocatalysts.

关键词： ZnCo2O4 nanosphere     CdS nanorods     photocatalytic hydrogen evolution    

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NO hydrogenation to NH over FeCu/TiO catalyst with improved activity

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 1973-1985 doi: 10.1007/s11705-023-2364-2

摘要： Ammonia is crucial in industry and agriculture, but its production is hindered by environmental concerns and energy-intensive processes. Hence, developing an efficient and environmentally friendly catalyst is imperative. In this study, we employed a straightforward and efficient impregnation technique to create various Cu-doped catalysts. Notably, the optimized 10Fe-8Cu/TiO2 catalyst exhibited exceptional catalytic performance in converting NO to NH3, achieving an NO conversion rate exceeding 80% and an NH3 selectivity exceeding 98% at atmospheric pressure and 350 °C. We employed in situ diffuse reflectance Fourier transform infrared spectroscopy and conducted density functional theory calculations to investigate the intermediates and subsequent adsorption. Our findings unequivocally demonstrate that Cu doping enhances the rate-limiting hydrogenation step and lowers the energy barrier for NH3 desorption, thereby resulting in improved NO conversion and enhanced selectivity toward ammonia. This study presents a pioneering approach toward energy-efficient ammonia synthesis and recycling of nitrogen sources.

关键词： NO hydrogenation     synthetic ammonia     10Fe-xCu/TiO2     high selectivity    

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Development of an integrated modeling system for improved multi-objective reservoir operation

Lei WANG, Cho Thanda NYUNT, Toshio KOIKE, Oliver SAAVEDRA, Lan Chau NGUYEN, Tran van SAP,

《结构与土木工程前沿（英文）》 2010年 第4卷 第1期   页码 47-55 doi: 10.1007/s11709-010-0001-x

摘要： Reservoir is an efficient way for flood control and improving all sectors related to water resources in the integrated water resources management. Moreover, multi-objective reservoir plays a significant role in the development of a country’s economy especially in developing countries. All multi-objective reservoirs have conflicts and disputes in flood control and water use, which makes the operator a great challenge in the decision of reservoir operation. For improved multi-objective reservoir operation, an integrated modeling system has been developed by incorporating a global optimization system (SCE-UA) into a distributed biosphere hydrological model (WEB-DHM) coupled with the reservoir routing module. The new integrated modeling system has been tested in the Da River subbasin of the Red River and showed the capability of reproducing observed reservoir inflows and optimizing the multi-objective reservoir operation. First, the WEB-DHM was calibrated for the inflows to the Hoa Binh Reservoir in the Da River. Second, the WEB-DHM coupled with the reservoir routing module was tested by simulating the reservoir water level, when using the observed dam outflows as the reservoir release. Third, the new integrated modeling system was evaluated by optimizing the operation rule of the Hoa Binh Reservoir from 1 June to 28 July 2006, which covered the annual largest flood peak. By using the optimal rule for the reservoir operation, the annual largest flood peak at downstream control point (Ben Ngoc station) was successfully reduced (by about 2.4m for water level and 2500m·s for discharge); while after the simulation periods, the reservoir water level was increased by about 20m that could supply future water use.

关键词： distributed biosphere hydrological model (WEB-DHM)     optimization     multi-objective reservoir     the Red River basin    

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An improved algorithm for McDowell’s analytical model of residual stress

null

《机械工程前沿（英文）》 2014年 第9卷 第2期   页码 150-155 doi: 10.1007/s11465-014-0295-9

摘要：

The analytical model for two-dimensional elastoplastic rolling/sliding contact proposed by McDowell is an important tool for predicting residual stress in rolling/sliding processes. In application of the model, a problem of low predicting precision near the surface layer of the component is found. According to the volume-constancy of plastic deformation, an improved algorithm for McDowell’s model is proposed in order to improve its predicting accuracy of the surface residual stress. In the algorithm, a relationship between three normal stresses perpendicular to each other at any point within the component is derived, and the relationship is applied to McDowell’s model. Meanwhile, an unnecessary hypothesis proposed by McDowell can be eliminated to make the model more reasonable. The simulation results show that the surface residual stress predicted by modified method is much closer to the FEM results than the results predicted by McDowell’s model under the same simulation conditions.

关键词： residual stress     McDowell’s model     volume-constancy of plastic deformation     FEM     elastoplastic rolling/sliding contact    

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Function-reversible facets enabling SrTiO nanocrystals for improved photocatalytic hydrogen evolution

《能源前沿（英文）》 doi: 10.1007/s11708-023-0894-4

摘要： It has been widely reported that, for faceted nanocrystals, the two adjacent facets with different band levels contribute to promoted charge separation, and provide active sites for photocatalytic reduction and oxidation reaction, respectively. In such cases, only one family of facets can be used for photocatalytic hydrogen evolution. Herein, by using SrTiO3 nanocrystals enclosed by {023} and {001} facets as a model photocatalyst, this paper proposed a strategy to achieve the full-facets-utilization of the nanocrystals for photocatalytic hydrogen via chemically depositing Pt nanoparticles on all facets. The photo-deposition experiment of CdS provided direct evidence to demonstrate that the {023} facets which were responsible for photooxidation reaction can be function-reversed for photocatalytic hydrogen evolution after depositing Pt nanoparticles, together with the {001} facets. Thus, the full-facets-utilization led to a much-improved activity for photocatalytic hydrogen, in contrast to those SrTiO3 nanocrystals with only {001} facets deposited by Pt nanoparticles via a photo-deposition method.

关键词： SrTiO3 nanocrystals     crystal facets     photocatalysis     hydrogen evolution    

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Electrodeposited porous Pb electrode with improved electrocatalytic performance for the electroreduction

Jing WANG, Hua WANG, Zhenzhen HAN, Jinyu HAN

《化学科学与工程前沿（英文）》 2015年 第9卷 第1期   页码 57-63 doi: 10.1007/s11705-014-1444-8

摘要： A porous Pb foam was fabricated electrochemically at a copper substrate and then used as the cathode for the electroreduction of CO . The surface morphology and composition of the porous Pb electrode was characterized by scanning electron microscopy, X-ray diffraction, transmission electron microscopy and selected area electron diffraction. The honeycomb-like porous structure was composed of needle-like Pb deposits. Cyclic voltammetry studies demonstrated that the porous Pb electrode had better electrocatalytic performance for the formation of formic acid from CO compared with a Pb plate electrode. The increase in current density was due to the large surface area of the porous Pb electrode, which provides more active sites on the electrode surface. The improved formic acid selectivity was due to the morphology of the roughened surface, which contains significantly more low-coordination sites which are more active for CO reduction. The highest current efficiency for formic acid was 96.8% at -1.7 V versus saturated calomel electrode at 5 °C. This porous Pb electrode with good catalytic abilities represents a new 3D porous material with applications for the electroreduction of CO .

关键词： electrodeposited porous Pb     carbon dioxide     electroreduction     formic acid    

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标题 作者 时间 类型 操作

LARGE-SCALE FARMING BENEFITS SOIL ACIDIFICATION ALLEVIATION THROUGH IMPROVED FIELD MANAGEMENT IN BANANA

期刊论文

Cluster voltage control method for “Whole County” distributed photovoltaics based on improved differential

期刊论文

Manufacturing system modeling and performance evaluation based on improved stochastic statechart

ZHANG Guojun, HE Jiabing, ZHU Haiping, CHEN Xuan

期刊论文

Time of flight improved thermally grown oxide thickness measurement with terahertz spectroscopy

期刊论文

A method for predicting consolidation settlements of floating column improved clayey subsoil

Jinchun CHAI, Supasit PONGSIVASATHIT,

期刊论文

Dynamic characteristics and improved MPPT control of PV generator

Houda BRAHMI, Rachid DHIFAOUI

期刊论文

operation of energy at hydrothermal power plants by simultaneous minimization of pollution and costs using improved

Homayoun EBRAHIMIAN,Bahman TAHERI,Nasser YOUSEFI

期刊论文

Innovative hybrid reinforcement constituting conventional longitudinal steel and FRP stirrups for improved

Mostafa FAKHARIFAR,Ahmad DALVAND,Mohammad K. SHARBATDAR,Genda CHEN,Lesley SNEED

期刊论文

SARS-CoV-2 vaccine research and immunization strategies for improved control of the COVID-19 pandemic

期刊论文

Design and synthesis of ZnCoO/CdS for substantially improved photocatalytic hydrogen production

期刊论文

NO hydrogenation to NH over FeCu/TiO catalyst with improved activity

期刊论文

Development of an integrated modeling system for improved multi-objective reservoir operation

Lei WANG, Cho Thanda NYUNT, Toshio KOIKE, Oliver SAAVEDRA, Lan Chau NGUYEN, Tran van SAP,

期刊论文

An improved algorithm for McDowell’s analytical model of residual stress

null

期刊论文

Function-reversible facets enabling SrTiO nanocrystals for improved photocatalytic hydrogen evolution

期刊论文

Electrodeposited porous Pb electrode with improved electrocatalytic performance for the electroreduction

Jing WANG, Hua WANG, Zhenzhen HAN, Jinyu HAN

期刊论文