Resource Type

Journal Article 769

Conference Videos 33

Conference Information 9

Year

2024 4

2023 69

2022 75

2021 74

2020 49

2019 66

2018 57

2017 47

2016 44

2015 17

2014 9

2013 14

2012 31

2011 14

2010 7

2009 23

2008 26

2007 38

2006 20

2005 27

open ︾

Keywords

Additive manufacturing 5

Neural network 5

cyberspace security 5

cyberspace 4

3D printing 3

Artificial intelligence 3

Biomaterial 3

neural network 3

spacecraft 3

5G 2

Accelerator 2

Adaptive control 2

Anomaly detection 2

Attention mechanism 2

China's space activities 2

Controller placement 2

Deep learning 2

Fault-tolerant control 2

GPS 2

open ︾

Search scope:

排序: Display mode:

A stepless-power-reconfigurable converter for a constant current underwater observatory Research Article

Yujia Zang, Yanhu Chen, Canjun Yang, Haoyu Zhang, Zhiyong Duan, Gul Muhammad,yanhuchen@zju.edu.cn

Frontiers of Information Technology & Electronic Engineering 2021, Volume 22, Issue 12,   Pages 1551-1684 doi: 10.1631/FITEE.2100259

Abstract: The conversion from constant current (CC) to constant voltage (CV) is one of the key technologies of CC systems. A with high stability and high reliability is usually used. Applications, however, are limited by high heat dissipation and low efficiency. In this paper, with an improved shunt regulation method, a novel concept of stepless power reconfiguration (SPR) for the CC/CV module is proposed. In cases with stable or slowly changing load, two modes of CC/CV conversion are proposed to reduce unnecessary power loss of the while being able to retain any operator-preset power margin in the system: (1) the manual SPR (MSPR) method based on single-loop control method; (2) the automatic SPR (ASPR) method based on inner-outer loop control method. The efficiency of the system is analyzed. How to select some key parameters of the system is discussed. Experimental results show that MSPR and ASPR are both effective and practical methods to reduce heat dissipation and improve the efficiency of the CC/CV module, while the high stability of the remains.

Keywords: 恒流/恒压转换;并联稳压器;无级功率重构;水下观测网    

Development of Marine Equipment for Underwater Stereoscopic Observation

Ma Rui, Zhao Xiutao, Liu Cungen

Strategic Study of CAE 2020, Volume 22, Issue 6,   Pages 19-25 doi: 10.15302/J-SSCAE-2020.06.003

Abstract:

Establishing an underwater stereoscopic observation network to obtain scientific, real-time, and comprehensive data is an important direction for understanding and exploiting the ocean in the future. This study first analyzes the need and necessity of developing the underwater stereoscopic observation equipment, then introduces the development status of the equipment in China and abroad, further analyzes the problems faced by China’s field development, and presents the key breakthrough points of marine sensors which serve as the key link for underwater observation. China has made great progress in technologies regarding marine observation platforms, but it still lags behind the world advanced level in key marine sensors and high-precision sensors. The big data obtained from ocean observation does not match the actual demand, and the ocean sensors lack the support from an improved platform. To guide the long-term development of related fields, we suggest that China should support the efficient transformation of research results of key marine sensors, coordinate the management of the marine equipment for underwater stereoscopic observation, and establish a national public test platform for offshore instruments and equipment.

Keywords: ocean observation     sea floor observatory network     underwater vehicle     underwater sensor    

Power system design for constant current subsea observatories Regular Article

Yan-hu Chen, Sa Xiao, De-jun Li,yanhuchen@zju.edu.cn,sxiao@zju.edu.cn,li_dejun@zju.edu.cn

Frontiers of Information Technology & Electronic Engineering 2019, Volume 20, Issue 11,   Pages 1505-1515 doi: 10.1631/FITEE.1800362

Abstract: Constant current power transmission is considered a good choice for subsea observatories due to its high resistance to shunt faults. A constant current subsea is planned to be constructed in the East China Sea. We discuss a constant current subsea system used for scientific experiments. The power system and its system are carefully designed. The power conversion method is challenging due to the use of constant current power, which is considerably different from traditional power systems. Thus, we adopt power compensation circuits in the conversion system to obtain a constant 48-V output for science users. A power management system that performs overvoltage protection and real-time monitoring and control of junction box is discussed. An innovative structure of a junction box is designed in consideration of a sealed working environment to extend the useful life of the junction box. Simulations and experiments reveal that the system has high efficiency and stability, especially in long-term applications.

Keywords: 海底观测网;电能变换;散热    

A new approach for analyzing the effect of non-ideal power supply on a constant current underwater cabled system Personal View

Yu-jia ZANG, Yan-hu CHEN, Can-jun YANG, De-jun LI, Ze-jian CHEN, Gul MUHAMMAD

Frontiers of Information Technology & Electronic Engineering 2020, Volume 21, Issue 4,   Pages 604-614 doi: 10.1631/FITEE.1800737

Abstract: The effect of a constant current (CC) power supply on the CC ocean observation system is a problem that once was neglected. The dynamic characteristics of the CC power supply may have great influence on the whole system, especially the voltage behavior in the event of load change. This needs to be examined. In this paper, a method is introduced to check whether the CC power supply can satisfy the dynamic requirements of the CC ocean observation system. An equivalent model to describe the non-ideal CC power supply is presented, through which the dynamic characteristics can be standardized. To verify the feasibility of this model, a minimum system of a single node in the CC ocean observation system is constructed, from which the model is derived. Focusing on the power failure problem, the output voltage responses are performed and the models are validated. Through the model, the dynamic behavior of the CC power supply is checked in a practical design.

Keywords: Non-ideal power supply     Constant current input     Ocean observation system    

Research Progress of Marine Scientific Equipment and Development Recommendations in China

Song Xiancang, Du Junfeng, Wang Shuqing, Li Huajun

Strategic Study of CAE 2020, Volume 22, Issue 6,   Pages 76-83 doi: 10.15302/J-SSCAE-2020.06.010

Abstract:

Marine scientific equipment is an essential tool for better understanding oceans, and it is also the foundation for exploiting and protecting oceans. This study analyzes the urgent requirements for developing highly efficient marine scientific equipment in China from four aspects, including understanding oceans, exploring oceans, protecting oceans, and maintaining ocean rights and interests. In addition, it provides reviews on the state-of-the-art techniques associated with the marine scientific observation platforms, namely air–sea interface observation platform, mobile underwater observation platform, and seafloor observation network system, in the countries that are believed to lead the field, and the development trends associated therewith are then identified. The remarkable achievements obtained in marine scientific equipment in China are presented such as the marine remote-sensing satellites, marine research ships, deep-diving submersibles, and seafloor observation networks. By comparing to the international advanced level, the issues China encountered in the general technologies, core equipment, and integrated system of marine scientific equipment are given. Several key development suggestions associated with the marine scientific equipment development in China are provided in terms of basic theories and key technologies, novel equipment development and achievement conversion, sharing mechanism and service platform, as well as international cooperation and standard system establishment, enabling the marine scientific equipment to better serve the implementation of the national marine power strategy.

Keywords: marine scientific equipment     deep-sea observation platform     air–sea interface observation     mobile underwater observation     seafloor observation network     equipment development    

A novel PV sub-module-level power-balancing topology for maximum power point tracking under partial shading and mismatch conditions Article

Mustafa GOKDAG,Mehmet AKBABA

Frontiers of Information Technology & Electronic Engineering 2016, Volume 17, Issue 12,   Pages 1388-1396 doi: 10.1631/FITEE.1500322

Abstract: Partial shading and mismatch conditions among the series-connected modules/sub-modules suffer from a nonconvex power curve with multiple local maxima and decreased peak power for the whole string. Energy transfer between the sub-modules brings them to the same operating voltage, and this collective operation produces a convex power curve, which results in increased peak power for the string. The proposed topology benefits from the switched-capacitor (SC) converter concept and is an applica-tion for sub-module-level power balancing with some novelties, including stopping the switching in absence of shading, string-level extension, and a reduced number of power electronics components as compared to those in the literature. Reduction in the number of power electronics components is realized by the fact that two sub-modules share one SC converter. This leads to reduced power electronics losses as well as less cost and volume of the converter circuit. Insertion loss analysis of the topology is presented. The proposed topology is simulated in the PSpice environment, and a prototype is built for experimental verification. Both simulation and experimental results confirm the loss analysis. This proves that with the proposed topology it is possible to extract almost all the power available on the partially shaded string and transfer it to the load side.

Keywords: Sub-module-level maximum power point tracking (MPPT)     Differential power processing (DPP)     Distributed power converters     Switched-capacitor (SC) converters    

Use of a coded voltage signal for cable switching and fault isolation in cabled seafloor observatories None

Zhi-feng ZHANG, Yan-hu CHEN, De-jun LI, Bo JIN, Can-jun YANG, Jun WANG

Frontiers of Information Technology & Electronic Engineering 2018, Volume 19, Issue 11,   Pages 1328-1339 doi: 10.1631/FITEE.1601843

Abstract:

Cabled seafloor observatories play an important role in ocean exploration for its long-term, real-time, and in-situ observation characteristics. In establishing a permanent, reliable, and robust seafloor observatory, a highly reliable cable switching and fault isolation method is essential. After reviewing the advantages and disadvantages of existing switching methods, we propose a novel active switching method for network configuration. Without additional communication path requirements, the switching method provides a way to communicate with a shore station through an existing power transmission path. A coded voltage signal with a distinct sequence is employed as the communication medium to transmit commands. The analysis of the maximum bit frequency of the voltage signals guarantees the accuracy of command recognition. A prototype based on the switching method is built and tested in a laboratory environment, which validated the functionality and reliability of the method.

Keywords: Cabled seafloor observatories     Cable switching and fault isolation     Coded voltage signal     Maximum bit frequency    

Controller area network node reliability assessment based on observable node information Article

Lei-ming ZHANG, Long-hao TANG, Yong LEI

Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 5,   Pages 615-626 doi: 10.1631/FITEE.1601029

Abstract: Controller area network (CAN) based fieldbus technologies have been widely used in networked manufacturing systems. As the information channel of the system, the reliability of the network is crucial to the system throughput, product quality, and work crew safety. However, due to the inaccessibility of the nodes’ internal states, direct assessment of the reliability of CAN nodes using the nodes’ internal error counters is infeasible. In this paper, a novel CAN node reliability assessment method, which uses node’s time to bus-off as the reliability measure, is proposed. The method estimates the transmit error counter (TEC) of any node in the network based on the network error log and the information provided by the observable nodes whose error counters are accessible. First, a node TEC estimation model is established based on segmented Markov chains. It considers the sparseness of the distribution of the CAN network errors. Second, by learning the differences between the model estimates and the actual values from the observable node, a Bayesian network is developed for the estimation updating mechanism of the observable nodes. Then, this estimation updating mechanism is transferred to general CAN nodes with no TEC value accessibility to update the TEC estimation. Finally, a node reliability assessment method is developed to predict the time to reach bus-off state of the nodes. Case studies are carried out to demonstrate the effectiveness of the proposed methodology. Experimental results show that the estimates using the proposed model agree well with actual observations.

Keywords: Controller area network (CAN)     Transmit error counter (TEC)     TEC value estimation     Bayesian network     Bus-off hitting time    

Thoughts on the Designs, Applications, Trends, and Challenges of Underwater Observation Information Systems

Shi Suixiang,Li Zhanbin,Hua Yanning,Cheng Yiyuan and Liu Feng

Strategic Study of CAE 2016, Volume 18, Issue 2,   Pages 61-65 doi: 10.15302/J-SSCAE-2016.02.007a

Abstract:

Promoting the creation of functional underwater observation information systems is an urgent priority for China’s national maritime defense, its ability to preserve its maritime rights, and marine disaster prevention and management. It is also an requirement of civil-military integration development to fulfill the overlapping missions of the Chinese military and civil government agencies. This paper reviews the current state of affairs and the ongoing trends in the field of underwater observation information systems in China and abroad. This study analyzes the problems faced by researchers and users in the development of underwater observation information system. The paper concludes by proposing a strategic goal, identifying the key projects and making policy recommendations for underwater observation information systems for stakeholders to consider.

Keywords: underwater observation     information system     key projects     policy recommendations    

Optimal communication frequency for switching cabled ocean networks with commands carried over the power line Research Article

Yan-hu Chen, Yu-jia Zang, Jia-jie Yao, Gul Muhammad,yanhuchen@zju.edu.cn

Frontiers of Information Technology & Electronic Engineering 2019, Volume 20, Issue 10,   Pages 1331-1343 doi: 10.1631/FITEE.1900125

Abstract: s with tree or ring topologies play an important role in real-time ocean exploration. Due to the time-consuming need for field maintenance, technology that can actively switch the power on/off on certain branches of the network becomes essential for enhancing the reliability and availability of the network. In this paper, a novel switching-control method is proposed, in which we invert the power transmission polarity and use the current on the power line as the digital signal at low frequency to broadcast information with the address and commands to the network, and the corresponding (BU) can decode and execute the switching commands. The cable’s parasitic parameters, the network scale, and the number of BUs, as the influencing factors of the on the power line, are theoretically studied and simulated. An optimized frequency that balances the executing accuracy and rate is calculated and proved on a simulated prototype. The results showed that the technology with optimized frequency can enhance the switching accuracy and configuring rate.

Keywords: 海缆开断;海洋观测网;分支单元;传输线理论;通信频率    

Research of an Interleaved Low-Voltage/High-Current DC-DC Converter

Wang Ping,Sun Xu,Song Liangyu

Strategic Study of CAE 2005, Volume 7, Issue 4,   Pages 59-63

Abstract:

In the recent years, the operating voltages of most high-performance microprocessors were lower than that of the previous ones and the research of low-voltage/high-current DC-DC converter was enhanced. Among all topologies, the current-doublers topology is optional. In the current-doublers topology, the ripple current of the output filter capacitor is reduced because the ripple current of the two inductors partially cancel each other and the required value of the filter inductance is significantly decreased. To further decrease the ripple current of output filter capacitor, this paper introduce a new method that a few of current-doublers are interleaved. This paper gives the switch signal waveforms and simulation model of the circuit. PSpice is used, which is a simulation tool for electronic system. The result of simulation achieves the ideal effect. Finally, the design is tested by an experiment.

Keywords: low-voltage/high-current DC-DC converter     current-doublers     interleaved    

Development and Experiment Research of the Postprocessor for Parallel Kinematic Machine Tools

Li Tiemin,Ye Peiqing,Wang Jinsong

Strategic Study of CAE 2003, Volume 5, Issue 12,   Pages 80-86

Abstract:

Based on the structure of 6 - TPS parallel kinematic machine tools (PKMTs) with 6 degrees of freedom (DOF), the theory and procedure to generate control data is introduced. On the basis of above analysis, the functions and framework of a postprocessor for this type of machine tools is designed. Some important methods for carrying out the postprocessing of the machine are researched and demonstrated, including inner data transfer protocol by parameterized binary data, interpolating algorithm in Descartes coordinate system, planar and spatial tool radius compensation, preprocessing of cutter location data, and word and syntax check of machining codes. Finally, a real machining experiment on the system mentioned above is introduced. The result shows that it can be successfully used in real manufacturing environment.

Keywords: parallel kinematic machine tools     postprocessing algorithm     postprocessor    

Status quo and outlook of reconfigurable research

Li Yufeng,Qiu Han,Lan Julong

Strategic Study of CAE 2008, Volume 10, Issue 7,   Pages 82-89

Abstract:

Today, with new services and applications blooming on the internet, to enable traditional routers to offer enough capability and speed of upgrade along with these services and applications in time would become even harder than ever. Run-time reconfiguration (RTR), based on the Field Programmable Gate Array (FPGA), is a new promising technology that can configure the partial or total hardware logic resources of a system at run time. Based on the technology, reconfigurable routers can support dynamic reconfiguration of new hardware logic for the new service, while keeping the other services still run properly, hence can provide a new possible solution to the update problem of the traditional routers. After introducing the basic concepts of RTR and the current development of the FPGA, this paper summarizes the past major research efforts with respect to the reconfigurable router, as well as the current work on it. Research directions and open problems are also discussed from the point of view of reconfigurable network.

Keywords: internet     reconfigurable router     reconfigurable network     programmable hardware    

Study and Application of Steady Flow and Unsteady Flow Mathematical Model for Canal Networks

Zhang Mingliang,Shen Yongming

Strategic Study of CAE 2007, Volume 9, Issue 8,   Pages 92-96

Abstract:

Based on Preissmann implicit scheme for one-dimensional Saint-Venant Equation,  the mathematical model for one- dimensional river networks and canal networks is developed and the key issues on the model are expatiated particularly in this paper.  This model is applied to simulating the tree-type irrigation canal networks and complex looped canal networks.  The results of levels and flows and discharge distribution between the branches agree with the data from Adlul.  This model is a simple and practical tool for water resource regulation of irrigation canal networks and river networks.  These results show the application value of this model is to set up ecological numerical model of water quality in river networks and canal networks.

Keywords: Preissmann implicit scheme     canal networks and river networks     discharge distribution     water quality mode    

Pattern reconfigurable antenna array for 5.8 GHz WBAN applications

杨凌升,王斌,李雅洁

Frontiers of Information Technology & Electronic Engineering 2023, Volume 24, Issue 9,   Pages 1357-1365 doi: 10.1631/FITEE.2200542

Abstract: 本文提出一种适用于5.8 GHz WBAN应用的方向图可重构天线阵列。天线阵列由辐射组件和控制网络组件组成。辐射组件包括4个平面F型天线,它们位于上层的4个角上,彼此逆时针旋转90°。控制网络组件位于底层,包括一个4端口可控网络。通过控制集成在可控网络中的PIN二极管,可以获得与人体表面相切的全向辐射图和与人体表面垂直的定向辐射图。我们测量了阵列安装在人体或前臂假体上时的阻抗带宽、辐射模式和增益,实验结果与仿真结果一致。同时仿真了两种辐射模式下的电磁波吸收比值(SAR)和波束切换能力,以确保该阵列的实用性。

Keywords: 无线体域网     方向图可重构     PIN二极管     控制网络     比吸收率    

Title Author Date Type Operation

A stepless-power-reconfigurable converter for a constant current underwater observatory

Yujia Zang, Yanhu Chen, Canjun Yang, Haoyu Zhang, Zhiyong Duan, Gul Muhammad,yanhuchen@zju.edu.cn

Journal Article

Development of Marine Equipment for Underwater Stereoscopic Observation

Ma Rui, Zhao Xiutao, Liu Cungen

Journal Article

Power system design for constant current subsea observatories

Yan-hu Chen, Sa Xiao, De-jun Li,yanhuchen@zju.edu.cn,sxiao@zju.edu.cn,li_dejun@zju.edu.cn

Journal Article

A new approach for analyzing the effect of non-ideal power supply on a constant current underwater cabled system

Yu-jia ZANG, Yan-hu CHEN, Can-jun YANG, De-jun LI, Ze-jian CHEN, Gul MUHAMMAD

Journal Article

Research Progress of Marine Scientific Equipment and Development Recommendations in China

Song Xiancang, Du Junfeng, Wang Shuqing, Li Huajun

Journal Article

A novel PV sub-module-level power-balancing topology for maximum power point tracking under partial shading and mismatch conditions

Mustafa GOKDAG,Mehmet AKBABA

Journal Article

Use of a coded voltage signal for cable switching and fault isolation in cabled seafloor observatories

Zhi-feng ZHANG, Yan-hu CHEN, De-jun LI, Bo JIN, Can-jun YANG, Jun WANG

Journal Article

Controller area network node reliability assessment based on observable node information

Lei-ming ZHANG, Long-hao TANG, Yong LEI

Journal Article

Thoughts on the Designs, Applications, Trends, and Challenges of Underwater Observation Information Systems

Shi Suixiang,Li Zhanbin,Hua Yanning,Cheng Yiyuan and Liu Feng

Journal Article

Optimal communication frequency for switching cabled ocean networks with commands carried over the power line

Yan-hu Chen, Yu-jia Zang, Jia-jie Yao, Gul Muhammad,yanhuchen@zju.edu.cn

Journal Article

Research of an Interleaved Low-Voltage/High-Current DC-DC Converter

Wang Ping,Sun Xu,Song Liangyu

Journal Article

Development and Experiment Research of the Postprocessor for Parallel Kinematic Machine Tools

Li Tiemin,Ye Peiqing,Wang Jinsong

Journal Article

Status quo and outlook of reconfigurable research

Li Yufeng,Qiu Han,Lan Julong

Journal Article

Study and Application of Steady Flow and Unsteady Flow Mathematical Model for Canal Networks

Zhang Mingliang,Shen Yongming

Journal Article

Pattern reconfigurable antenna array for 5.8 GHz WBAN applications

杨凌升,王斌,李雅洁

Journal Article