资源类型

期刊论文 264

会议视频 4

年份

2024 1

2023 18

2022 25

2021 15

2020 23

2019 17

2018 15

2017 23

2016 14

2015 13

2014 13

2013 7

2012 12

2011 2

2010 7

2009 7

2008 10

2007 7

2006 9

2005 4

展开 ︾

关键词

遗传算法 22

优化 3

2021全球十大工程成就 2

加速遗传算法 2

神经网络 2

移动边缘计算 2

稀土元素 2

2020全球工程前沿 1

6G；关键技术；通信标准；网络安全；数字经济 1

BP神经网络 1

Colebrook隐式方程 1

Cu(In 1

Ga)Se2 1

IPv6 1

IP核心网 1

PDT 1

Powell法 1

REC114 1

TD-LAS 1

展开 ︾

检索范围：

排序： 展示方式：

Assessment of mobile and potential mobile trace elements extractability in calcareous soils using different

Mohsen Jalali, Ziba Hurseresht

《环境科学与工程前沿（英文）》 2020年 第14卷 第1期 doi: 10.1007/s11783-019-1186-4

摘要： DTPA and NH4OAc, HNO3 and EDTA, and MgCl2 and NH4NO3 had similar behavior. In NH4OAc, DTPA, and EDTA, the possibility of re-adsorption of trace elements is low. CaCl2 may be more suitable than other extracts in calcareous soils. Understanding trace elements mobility in soils, extracting agents, and their relationships with soil components, are essential for predicting their movement in soil profile and availability to plants. A laboratory study was conducted to evaluate extractability of cadmium (Cd), cobalt (Co), copper (Cu), nickel (Ni), and zinc (Zn) from calcareous soils utilizing various extracting agents to be specific CaCl2, DTPA, EDTA, HNO3, MgCl2, NaNO3, NH4NO3, and NH4OAc. Cluster analysis indicated that DTPA and NH4OAc, HNO3 and EDTA, and MgCl2 and NH4NO3 extracting agents yielded comparative values, whereas NaNO3 and CaCl2 have shown different behavior than other extracting agents for all studied trace elements. The speciation of extracted trace elements in solutions indicated that in the CaCl2, NaNO3, NH4NO3, and MgCl2 extracting agents most extracted Cd, Co, Ni, Zn, and part of Cu were as free ions and may be re-adsorbed on soils, leading to lower extractability, whereas, in the case of HNO3 extracting agent, the likelihood of re-adsorption of trace elements may be little. The results of speciation of trace elements using NH4OAc, DTPA, and EDTA extracting agents showed that Me-(Acetate)3–, Me-(Acetate)2(aq), Me(DTPA)3−, Me(EDTA)2−, and MeH(EDTA)– complexes dominated in solutions indicating that the extracted trace elements may not be re-adsorbed on soils, leading to higher extractability. The results of this study are useful for short and long-term evaluations of trace elements mobility and further environmental impacts.

关键词： Mobility     Calcareous soils     Extracting agents     Trace elements    

HTML PDF 收藏

Increasing prevalence of antibiotic resistance genes in manured agricultural soils in northern China

Nan Wu, Weiyu Zhang, Shiyu Xie, Ming Zeng, Haixue Liu, Jinghui Yang, Xinyuan Liu, Fan Yang

《环境科学与工程前沿（英文）》 2020年 第14卷 第1期 doi: 10.1007/s11783-019-1180-x

摘要： Manure application increased the abundances of ARGs and MGEs in agricultural soils. Five classes of ARGs and two MGEs were prevalent in manured and unfertilized soils. Genera Pseudomonas and Bacteroidetes might be the dominant hosts of intI1 and ermF. The abundances of ARGs positively correlated with TC, TN, OM, Cu, Zn, Pb and MGEs. Land application of manure tends to result in the dissemination of antibiotic resistance in the environment. In this study, the influence of long-term manure application on the enrichment of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) in agricultural soils was investigated. All the analyzed eight ARGs (tetA, tetW, tetX, sulI, sulII, ermF, aac(6’)-Ib-cr and blaTEM) and two MGEs (intI1 and Tn916/1545) were detected in both the manured and control soils, with relative abundances ranging from 10-6 to 10-2. Compared with the control soil, the relative abundances of ARGs and MGEs in manured soils were enriched 1.0–18.1 fold and 0.6–69.1 fold, respectively. High-throughput sequencing analysis suggested that at the phylum level, the bacteria carrying intI1 and ermF might be mainly affiliated with Proteobacteria and Bacteroides, respectively. The dominant genera carrying intI1 and ermF could be Pseudomonas and Bacteroides, independent of manure application. Correlation analysis revealed that ARGs had strong links with soil physicochemical properties (TC, TN, and OM), heavy metals (Cu, Zn and Pb) and MGEs, indicating that the profile and spread of ARGs might be driven by the combined impacts of multiple factors. In contrast, soil pH and C/N exhibited no significant relationships with ARGs. Our findings provide evidence that long-term manure application could enhance the prevalence and stimulate the propagation of antibiotic resistance in agricultural soils.

关键词： Antibiotic resistance     Mobile genetic elements     Soil     Manure     Heavy metals    

HTML PDF 收藏

Research and practice on system engineering management of a mobile payment project

Yongkai ZHOU, Hongfeng CHAI

《工程管理前沿（英文）》 2017年 第4卷 第2期   页码 127-137 doi: 10.15302/J-FEM-2017011

摘要： The popularization of the mobile internet has given rise to demand for flexible and convenient payment methods. For China, it is necessary to keep pace with or even lead the trend of innovation and development in the age of mobile payment. From the perspective of systems engineering, this paper introduces research and implementation of China UnionPay’s mobile payment project. The general requirements and core engineering problems of the mobile payment project are summarized based on analyses of the characteristics and engineering difficulties of this project. Integration of innovative technologies is introduced to resolve the contradiction between ease-of-use and security. A rapid iterative development process is adopted to improve the product release efficiency as well as the users' experience. The launch of the mobile payment project also opens the window to coordinating and upgrading the whole payment industry chains.

关键词： systems engineering     mobile payment     engineering management method     Mobile QuickPass     national information security     rapid iteration process     financial security     coordination and cooperation    

HTML PDF 收藏

Linking elements to outcomes of knowledge transfer in the project environment: Current review and future

《工程管理前沿（英文）》 2022年 第9卷 第2期   页码 221-238 doi: 10.1007/s42524-022-0195-3

摘要： A project is a specific effort to create a unique product, so it is a favorable place for knowledge creation and development. Knowledge can be transferred inside and outside projects and their parent project-based organizations, thus affecting project performance and organizational competitiveness. However, the current research on the elements and outcomes of knowledge transfer (KT) in the project environment lacks completeness and clarity, and that on the different levels of KT is fragmented. This study aims to conduct comprehensive research to determine and link the elements and outcomes of KT in the project environment. The authors systematically analyzed the relevant literature from 2000 to 2021, which showed an increasing publication trend. They divided KT in the project environment into three levels according to the transfer scenario: Intra-project, cross-project, and cross-organizational KT. Five-dimensional transfer elements and two-dimensional transfer outcomes were then identified and analyzed from previous literature. Lastly, the relationships between the transfer elements and outcomes were gathered to create a comprehensive model. Importantly, the knowledge gap in the current literature was highlighted, and future research directions were put forward. This study builds a theoretical framework linking transfer elements to outcomes that can serve as a basis for scholars and practitioners to develop effective strategies for KT in the project environment.

关键词： knowledge transfer     knowledge management     project management     project environment     literature review    

HTML PDF 收藏

基于可拓学的设计方案进化推理方法

赵燕伟,,刘海生,张国贤

《中国工程科学》 2003年 第5卷 第5期   页码 63-69

摘要：

在分析现有概念设计求解策略的基础上，提出了基于可拓学理论与遗传算法相结合的概念设计求解模型。利用遗传算法模拟物元变换过程，建立了产品方案物元描述的内部模型和外部模型，探讨了内、外模型的转换关系并通过关联函数将内、外部模型联系起来。根据内部模型给出了遗传算法的编码形式以及与之相适应的交叉、变异策略，并通过可拓评价方法建立了遗传算法的适应值函数，基本解决了产品概念设计中的知识组合爆炸和矛盾冲突问题。最后通过求解减速器方案验证了该方法的可行性。

关键词： 概念设计     物元变换     遗传算法     进化推理     可拓评价    

HTML PDF 收藏

Motion control of multi-actuator hydraulic systems for mobile machineries: Recent advancements and future

Bing XU, Min CHENG

《机械工程前沿（英文）》 2018年 第13卷 第2期   页码 151-166 doi: 10.1007/s11465-018-0470-5

摘要：

This paper presents a survey of recent advancements and upcoming trends in motion control technologies employed in designing multi-actuator hydraulic systems for mobile machineries. Hydraulic systems have been extensively used in mobile machineries due to their superior power density and robustness. However, motion control technologies of multi-actuator hydraulic systems have faced increasing challenges due to stringent emission regulations. In this study, an overview of the evolution of existing throttling control technologies is presented, including open-center and load sensing controls. Recent advancements in energy-saving hydraulic technologies, such as individual metering, displacement, and hybrid controls, are briefly summarized. The impact of energy-saving hydraulic technologies on dynamic performance and control solutions are also discussed. Then, the advanced operation methods of multi-actuator mobile machineries are reviewed, including coordinated and haptic controls. Finally, challenges and opportunities of advanced motion control technologies are presented by providing an overall consideration of energy efficiency, controllability, cost, reliability, and other aspects.

关键词： motion control     electrohydraulic control     energy efficiency     mobile machineries    

HTML PDF 收藏

A family of non-conforming crack front elements of quadrilateral and triangular types for 3D crack problems

Guizhong XIE, Fenglin ZHOU, Hao LI, Xiaoyu WEN, Fannian MENG

《机械工程前沿（英文）》 2019年 第14卷 第3期   页码 332-341 doi: 10.1007/s11465-019-0540-3

摘要： This study focuses on establishing non-conforming crack front elements of quadrilateral and triangular types for 3D crack problems when the dual boundary element method is applied. The asymptotic behavior of the physical variables in the area near the crack front is fully considered in the construction of the shape function. In the developed quadrilateral and triangular crack front elements, the asymptotic term, which captures the asymptotic behavior of the physical variable, is multiplied directly by the conventional Lagrange shape function to form a new crack front shape function. Several benchmark numerical examples that consider penny-shaped cracks and straight-edge crack problems are presented to illustrate the validity and efficiency of the developed crack front elements.

关键词： Taylor expansion     crack front elements     stress intensity factors     dual boundary element method    

HTML PDF 收藏

A new efficient optimal path planner for mobile robot based on Invasive Weed Optimization algorithm

Prases K. MOHANTY,Dayal R. PARHI

《机械工程前沿（英文）》 2014年 第9卷 第4期   页码 317-330 doi: 10.1007/s11465-014-0304-z

摘要：

Planning of the shortest/optimal route is essential for efficient operation of autonomous mobile robot or vehicle. In this paper Invasive Weed Optimization (IWO), a new meta-heuristic algorithm, has been implemented for solving the path planning problem of mobile robot in partially or totally unknown environments. This meta-heuristic optimization is based on the colonizing property of weeds. First we have framed an objective function that satisfied the conditions of obstacle avoidance and target seeking behavior of robot in partially or completely unknown environments. Depending upon the value of objective function of each weed in colony, the robot avoids obstacles and proceeds towards destination. The optimal trajectory is generated with this navigational algorithm when robot reaches its destination. The effectiveness, feasibility, and robustness of the proposed algorithm has been demonstrated through series of simulation and experimental results. Finally, it has been found that the developed path planning algorithm can be effectively applied to any kinds of complex situation.

关键词： mobile robot     obstacle avoidance     Invasive Weed Optimization     navigation    

HTML PDF 收藏

Assessment of leaching behavior and human bioaccessibility of rare earth elements in typical hospital

Chunfeng Wang, Guanfei Chen, Yanchen Zhu, Dan Yao, Wanfeng Wang, Lianjun Wang

《环境科学与工程前沿（英文）》 2017年 第11卷 第6期 doi: 10.1007/s11783-017-0946-2

摘要： Leaching behavior and gastrointestinal bioaccessibility of rare earth elements (REEs) from hospital waste incineration (HWI) fly and bottom ash samples collected from Beijing and Nanjing Cities were assessed. In the same ash sample, the leaching concentrations of individual REEs determined by the Toxicity Characteristic Leaching Procedure (TCLP) were higher than those detected by the European standard protocol (EN-type test), thereby suggesting that the low pH value of leaching solution was an important factor influencing the leachability of REE. The REE bioaccessibility results, which were evaluated using the physiologically based extraction test (PBET), indicated that REEs were highly absorbed during gastric phase by dissolution; and subsequently precipitated and/or re-adsorbed in small intestinal phase. The relative amounts of the total REEs extracted by the TCLP method, EN-type test and PBET test were compared. In addition to the pH value of extraction solutions, the chelating role of REEs with organic ligands used in the PBET method was also an important parameter affecting REE adsorption in human body. Additionally, this study showed that REEs were extracted by these methods as concomitants of heavy metals and anions (NO , F , SO , and Cl ) from HWI ash, which probably caused the remarkably complex toxicity on human body by the exposure pathway.

关键词： Assessment     Rare earth elements     Leaching behavior     Bioaccessibility     Hospital waste    

HTML PDF 收藏

Preconcentration of trace elements by adsorption onto a niobium wire for electrothermal atomization atomic

Satoshi KANECO, Hiroaki KITANAGA, Hideyuki KATSUMATA, Tohru SUZUKI

《化学科学与工程前沿（英文）》 2012年 第6卷 第4期   页码 432-435 doi: 10.1007/s11705-012-1219-z

摘要： In the present work, a new preconcentration method of trace elements by adsorption onto a niobium wire has been developed for electrothermal atomization atomic absorption spectrometry (ETAAS) with a tungsten tube atomizer. Detection limits (pg·mL ) by this method combined with ETAAS were 45 for bismuth, 7.0 for cadmium, 20 for copper, 1.3 for gold, 36 for lead, 65 for manganese, 9.5 for rhodium and 19 for silver.

关键词： preconcentration     adsorption onto niobium wire     electrothermal atomization atomic absorption spectrometry     tungsten tube atomizer     trace elements    

HTML PDF 收藏

Output tracking control of mobile manipulators based on dynamical sliding-mode control

WUYuxiang, FENG Ying, HU Yueming

《机械工程前沿（英文）》 2007年 第2卷 第1期   页码 110-115 doi: 10.1007/s11465-007-0019-5

摘要： A dynamical sliding-mode controller is devised to track the output of mobile manipulators. During the investigation, firstly a reduced dynamic model considering the dynamics of the driving motor is developed for mobile manipulators. Then, the system is decomposed into four lower-dimensional subsystems by means of diffeomorphism and nonlinear input transformation. Moreover, a design method of the dynamical sliding-mode controller that is applied to the output tracking of mobile manipulators is proposed. The simulation results indicate that the dynamical sliding-mode controller can not only track the given trajectory correctly but also reduce the chattering of sliding-mode control system considerably.

关键词： lower-dimensional     nonlinear     trajectory     tracking     diffeomorphism    

HTML PDF 收藏

Analyzing the service availability of mobile cloud computing systems by fluid-flow approximation

Hong-wu LV,Jun-yu LIN,Hui-qiang WANG,Guang-sheng FENG,Mo ZHOU

《信息与电子工程前沿（英文）》 2015年 第16卷 第7期   页码 553-567 doi: 10.1631/FITEE.1400410

摘要： Mobile cloud computing (MCC) has become a promising technique to deal with computation- or data-intensive tasks. It overcomes the limited processing power, poor storage capacity, and short battery life of mobile devices. Providing continuous and on-demand services, MCC argues that the service must be available for users at anytime and anywhere. However, at present, the service availability of MCC is usually measured by some certain metrics of a real-world system, and the results do not have broad representation since different systems have different load levels, different deployments, and many other random factors. Meanwhile, for large-scale and complex types of services in MCC systems, simulation-based methods (such as Monte-Carlo simulation) may be costly and the traditional state-based methods always suffer from the problem of state-space explosion. In this paper, to overcome these shortcomings, fluid-flow approximation, a breakthrough to avoid state-space explosion, is adopted to analyze the service availability of MCC. Four critical metrics, including response time of service, minimum sensing time of devices, minimum number of nodes chosen, and action throughput, are defined to estimate the availability by solving a group of ordinary differential equations even before the MCC system is fully deployed. Experimental results show that our method costs less time in analyzing the service availability of MCC than the Markov- or simulation-based methods.

关键词： Service availability     Mobile cloud computing     Fluid-flow approximation     Ordinary differential equations    

HTML PDF 收藏

Human power-based energy harvesting strategies for mobile electronic devices

Dewei JIA, Jing LIU

《能源前沿（英文）》 2009年 第3卷 第1期   页码 27-46 doi: 10.1007/s11708-009-0002-4

摘要： Energy problems arise with the proliferation of mobile electronic devices, which range from entertainment tools to life saving medical instruments. The large amount of energy consumption and increasing mobility of electronic devices make it urgent that new power sources should be developed. It has been gradually recognized that the human body is highly flexible in generating applicable power from sources of heat dissipation, joint rotation, enforcement of body weight, vertical displacement of mass centers, and even elastic deformation of tissues and other attachments. These basic combinations of daily activities or metabolic phenomena open up possibilities for harvesting energy which is strong enough to power mobile or even implantable medical devices which could be used for a long time or be recharged permanently. A comprehensive review is presented in this paper on the latest developed or incubating electricity generation methods based on human power which would serve as promising candidates for future mobile power. Thermal and mechanical energy, investigated more thoroughly so far, will particularly be emphasized. Thermal energy relies on body heat and employs the property of thermoelectric materials, while mechanical energy is generally extracted in the form of enforcement or displacement excitation. For illustration purposes, the piezoelectric effect, dielectric elastomer and the electromagnetic induction couple, which can convert force directly into electricity, were also evaluated. Meanwhile, examples are given to explain how to adopt inertia generators for converting displacement energy via piezoelectric, electrostatic, electromagnetic or magnetostrictive vibrators. Finally, future prospects in harvesting energy from human power are made in conclusion.

关键词： mobile electronic device     human power     energy harvesting     micro/miniaturized generator     battery     green energy    

HTML PDF 收藏

Assessment of pollution of potentially harmful elements in soils surrounding a municipal solid waste

Ying Han, Huiting Xie, Wenbin Liu, Haifeng Li, Mengjing Wang, Xuebin Chen, Xiao Liao, Nan Yan

《环境科学与工程前沿（英文）》 2016年 第10卷 第6期 doi: 10.1007/s11783-016-0873-7

摘要： Potentially harmful elements in ambient soil of a MSWI were assessed. Spatial distribution of potential ecological risk index was investigated. Health risk assessment of potentially harmful elements in soil was evaluated. Hg in the soil posed health hazards to the local population. We assessed the contamination levels of Mn, Zn, Cr, Cu, Ni, Pb, As and Hg and the risks posed by these potentially harmful elements in top-soils around a municipal solid waste incinerator (MSWI). We collected 20 soil samples, with an average pH of 8.1, and another fly ash sample emitted from the MSWI to investigate the concentrations of these elements in soils. We determined the concentrations of these elements by inductively coupled plasma–optical emission spectrometer (ICP-OES), except for Hg, which we measured by AF-610B atomic fluorescence spectrometer ( ). We assessed the risks of these elements through the use of geoaccumulation index ( ), potential ecological risk index ( ), hazard quotient ( ) and cancer risk ( ). The results showed that concentrations of potentially harmful elements in soil were influenced by the wind direction, and the concentrations of most elements were higher in the area northwest of the MSWI, compared with the area southeast of the incinerator, with the exception of As; these results were in accordance with those results acquired from our contour maps. According to the values, some soil samples were clearly polluted by Hg emissions. However, the health risk assessment indicated that the concentrations of Hg and other elements in soil did not pose non-carcinogenic risks to the local populations. This was also the case for the carcinogenic risks posed by As, Cr, and Ni. The carcinogenic risk posed by As was higher, in the range 6.49 × 10 –9.58 × 10 , but this was still considered to be an acceptable level of risk.

关键词： Soil     Potentially harmful elements     Contamination     Kriging interpolation     Risk assessment     Wind direction    

HTML PDF 收藏

Biomedical sensor technologies on the platform of mobile phones

Lin LIU, Jing LIU

《机械工程前沿（英文）》 2011年 第6卷 第2期   页码 160-175 doi: 10.1007/s11465-011-0216-0

摘要：

Biomedical sensors have been widely used in various areas of biomedical practices, which play an important role in disease detection, diagnosis, monitoring, treatment, health management, and so on. However, most of them and their related platforms are generally not easily accessible or just too expensive or complicated to be kept at home. As an alternative, new technologies enabled from the mobile phones are gradually changing such situations. As can be freely available to almost everyone, mobile phone offers a unique way to improve the conventional medical care through combining with various biomedical sensors. Moreover, the established systems will be both convenient and low cost. In this paper, we present an overview on the state-of-art biomedical sensors, giving a brief introduction of the fundamental principles and showing several new examples or concepts in the area. The focus was particularly put on interpreting the technical strategies to innovate the biomedical sensor technologies based on the platform of mobile phones. Some challenging issues, including feasibility, usability, security, and effectiveness, were discussed. With the help of electrical and mechanical technologies, it is expected that a full combination between the biomedical sensors and mobile phones will bring a bright future for the coming pervasive medical care.

关键词： biomedical sensor     pervasive technology     mobile phone     combined system     health management    

HTML PDF 收藏

标题 作者 时间 类型 操作

Assessment of mobile and potential mobile trace elements extractability in calcareous soils using different

Mohsen Jalali, Ziba Hurseresht

期刊论文

Increasing prevalence of antibiotic resistance genes in manured agricultural soils in northern China

Nan Wu, Weiyu Zhang, Shiyu Xie, Ming Zeng, Haixue Liu, Jinghui Yang, Xinyuan Liu, Fan Yang

期刊论文

Research and practice on system engineering management of a mobile payment project

Yongkai ZHOU, Hongfeng CHAI

期刊论文

Linking elements to outcomes of knowledge transfer in the project environment: Current review and future

期刊论文

基于可拓学的设计方案进化推理方法

赵燕伟,,刘海生,张国贤

期刊论文

Motion control of multi-actuator hydraulic systems for mobile machineries: Recent advancements and future

Bing XU, Min CHENG

期刊论文

A family of non-conforming crack front elements of quadrilateral and triangular types for 3D crack problems

Guizhong XIE, Fenglin ZHOU, Hao LI, Xiaoyu WEN, Fannian MENG

期刊论文

A new efficient optimal path planner for mobile robot based on Invasive Weed Optimization algorithm

Prases K. MOHANTY,Dayal R. PARHI

期刊论文

Assessment of leaching behavior and human bioaccessibility of rare earth elements in typical hospital

Chunfeng Wang, Guanfei Chen, Yanchen Zhu, Dan Yao, Wanfeng Wang, Lianjun Wang

期刊论文

Preconcentration of trace elements by adsorption onto a niobium wire for electrothermal atomization atomic

Satoshi KANECO, Hiroaki KITANAGA, Hideyuki KATSUMATA, Tohru SUZUKI

期刊论文

Output tracking control of mobile manipulators based on dynamical sliding-mode control

WUYuxiang, FENG Ying, HU Yueming

期刊论文

Analyzing the service availability of mobile cloud computing systems by fluid-flow approximation

Hong-wu LV,Jun-yu LIN,Hui-qiang WANG,Guang-sheng FENG,Mo ZHOU

期刊论文

Human power-based energy harvesting strategies for mobile electronic devices

Dewei JIA, Jing LIU

期刊论文

Assessment of pollution of potentially harmful elements in soils surrounding a municipal solid waste

Ying Han, Huiting Xie, Wenbin Liu, Haifeng Li, Mengjing Wang, Xuebin Chen, Xiao Liao, Nan Yan

期刊论文

Biomedical sensor technologies on the platform of mobile phones

Lin LIU, Jing LIU

期刊论文