Identifying a device and detecting a change in its position is critical for secure devices management in the Internet of Things(IoT).In this paper,a device management system is proposed to track the devices by using a...Identifying a device and detecting a change in its position is critical for secure devices management in the Internet of Things(IoT).In this paper,a device management system is proposed to track the devices by using audio-based location distinction techniques.In the proposed scheme,traditional cryptographic techniques,such as symmetric encryption algorithm,RSA-based signcryption scheme,and audio-based secure transmission,are utilized to provide authentication,non-repudiation,and confidentiality in the information interaction of the management system.Moreover,an audio-based location distinction method is designed to detect the position change of the devices.Specifically,the audio frequency response(AFR)of several frequency points is utilized as a device signature.The device signature has the features as follows.(1)Hardware Signature:different pairs of speaker and microphone have different signatures;(2)Distance Signature:in the same direction,the signatures are different at different distances;and(3)Direction Signature:at the same distance,the signatures are different in different directions.Based on the features above,amovement detection algorithmfor device identification and location distinction is designed.Moreover,a secure communication protocol is also proposed by using traditional cryptographic techniques to provide integrity,authentication,and non-repudiation in the process of information interaction between devices,Access Points(APs),and Severs.Extensive experiments are conducted to evaluate the performance of the proposed method.The experimental results show that the proposedmethod has a good performance in accuracy and energy consumption.展开更多
In the context of 5G,the high-frequency cyclicity and inhomogeneity of heat flow put forward higher requirements for the thermal control system of electronic devices,and there is a great need for thermal management mo...In the context of 5G,the high-frequency cyclicity and inhomogeneity of heat flow put forward higher requirements for the thermal control system of electronic devices,and there is a great need for thermal management modules with fixed point and high efficiency to ensure the long-term development of electronic devices.Here,we selected four phase change molecules with significant differences in phase change temperatures to be composited with graphene aerogel(GA)to obtain Ei@GA,Tetra@GA,Octa@GA,and 1,10-Deca@GA.Compared with pure phase change molecules,the thermal conductivity has been increased by more than 20%,and the relative enthalpic efficiency is as high as 98.7%or more.Further,we assembled the four phase change composites by“reduction welding”to obtain the integrated,modular thermal management device M1-PCMs@GA.Simulation of inhomogeneous heat generation in electronics by building an inhomogeneous heat generation platform.Compared with the homogeneous modules M2-Ei@GA and M3-1,10-Deca@GA,the effective temperature control time of the customized module M1-PCMs@GA is extended by 100.0 and 394.3 s,respectively.Therefore,custom-assembled modular thermal management devices have important application prospects in the field of intelligent temperature control of electronic devices,and the idea of cascade assembly enriches the application functions and development direction of intelligent thermal managers.展开更多
With the expansion of the scale of our hospital robot laboratory, equipment use, reserves are increasing, manual management equipment information has been unable to adapt to daily management, such as data record error...With the expansion of the scale of our hospital robot laboratory, equipment use, reserves are increasing, manual management equipment information has been unable to adapt to daily management, such as data record error rate increased, the number of experiments increased, equipment loss and maintenance is not clearly defined. In order to ensure the safety and accuracy of the equipment, a system of equipment management systems was developed as a result of the conversion to the use of management systems for the recording and storage of information. The design of this system is a perfect robot laboratory equipment management system based on the development of web framework technology for equipment management functions. The back end of this system uses the Java language, the SSM framework as the main body, the database is built by MySQL relational database, the front-end page uses JSP, Bootstrap, jQuery and other technologies, and uses Eclipse project construction tools for system development. After a period of trial operation, the level of laboratory equipment management has been significantly improved.展开更多
Purpose The control network is a critical infrastructure that supports the stable operation of the accelerator.Each device accessing the control network has different device information,such as IP address,MAC address,...Purpose The control network is a critical infrastructure that supports the stable operation of the accelerator.Each device accessing the control network has different device information,such as IP address,MAC address,connected switches and ports,device location and purpose.Accurately maintaining the mapping relationship between these device information facilitates network management.It helps inventory assets,fault location and provide visibility into dynamic changes of device on the network.However,existing tools cannot fully satisfy these demands.They only map some information and lack details important for accelerator facilities like device location and purpose.Additionally,they only reflect the current status rather than indicating dynamic changes across all devices over time.As intelligent devices proliferate,the scale of the control network is rapidly expanding,posing greater challenges in maintaining mapping relationships.Methods This paper proposes a device information-centered Accelerator Control Network Management System(ACNMS).It establishes a device information management framework and allows network administrators to perceive the dynamic changes of devices on the network.The system adopts a layered architecture.Back-end modules implement the core logic of all functions.The graphical user interface presents data and provides a management portal.Results The system test on the control network of the National Synchrotron Radiation Laboratory demonstrates that it can meet the functional design objectives.The application scenarios of the ACNMS are further expanded through system integration and combination with network automation.Conclusion The ACNMS has proven to be an efficient network management tool that significantly improves the operation and maintenance efficiency of the accelerator control network.展开更多
Java technology is spreading rapidly all over the world in recent years. It is a popular application development language for its well-encapsulation, platform-independent and high security. There are great amounts of ...Java technology is spreading rapidly all over the world in recent years. It is a popular application development language for its well-encapsulation, platform-independent and high security. There are great amounts of Java games and other gadgets on mobile platforms, as well as on set-up-box systems. As Java applications become more sophisticated, the Java Virtual Machine (JVM) mid-dle-wares in embedded systems are not satisfying, Java-specific chips extend in the market. All existing Java-based system software or Operating System (OS) are used on JVM, they cannot be used on Java processors. It is important to develop a pure Java system software or OS so that embedded systems using Java processors will have great performance in Java applications. This paper presents a set of system software designed for a Java-specified processor VP6K, which is also a System-on-Chip (SoC). This system software includes real-time multitask dispatching, file management, device management, hardware drivers, and infrastructural Application Programming Interface (APIs). According to ex-perimental results, the system software provides interfaces for Java programs to fully handle CPU resource, so that all applications can be executed properly and efficiently. VP6K embedded platform shows its good performance for Java applications when the system software is implemented.展开更多
The interior comer flow theory is fundamental for liquid management in space. In this paper, the interior comer flow theory is modified by correction of the curvature and shape parameters based on geometry relationshi...The interior comer flow theory is fundamental for liquid management in space. In this paper, the interior comer flow theory is modified by correction of the curvature and shape parameters based on geometry relationship, so that it can be extended to a wide range of applications including different dihedral angles and contact angles. This modification is validated with the data provided by the references using capillary tube and drop tower. Besides, the errors between the theory and experiment value are analyzed for the case of small viscosity and the long-time flow, finding that the main reason causing the error is the transformation of the flow resistance along the flow path. At last, the theory of interior comer flow is applied to the primary design of the Propellant Management Device in satellite tank, and optimum design of the vanes is given in terms of maximum flow rate.展开更多
The aim of this paper is to present a new topology of a DC-DC power converter for conditioning the current and voltages behaviors of embarked energy sources used in electrical vehicles. The fuel cells in conjunction w...The aim of this paper is to present a new topology of a DC-DC power converter for conditioning the current and voltages behaviors of embarked energy sources used in electrical vehicles. The fuel cells in conjunction with ultra-capacitors have been chosen as the power supply. The originality of the proposed converter is to use a variable voltage of the DC bus of the vehicle. The goal is to allow a better energy management of the embedded sources onboard the vehicle by improving its energy efficiency. After presenting and explaining the topology of the converter, some simulation and experiments results are shown to highlight its different operation modes.展开更多
Recently, Terminal has become one of the key issues in the 3G development. In the paper, we study the mobile terminal management in 3G network. Based on the analysis of problems encountered with the terminals, the pa...Recently, Terminal has become one of the key issues in the 3G development. In the paper, we study the mobile terminal management in 3G network. Based on the analysis of problems encountered with the terminals, the paper describes the use cases of terminal management. A system architecture with its function components of mobile terminal management system is proposed. Moreover, a possible implementation solution is introduced and described. A Management Information Model （MIM） for terminal management is also proposed to support the management services.展开更多
The superior radiation tolerance of silicon-on-insulator(SOI)wafers makes them critical for next-generation integrated circuit and micro-electro-mechanical system electronics in space technology and nuclear energy,and...The superior radiation tolerance of silicon-on-insulator(SOI)wafers makes them critical for next-generation integrated circuit and micro-electro-mechanical system electronics in space technology and nuclear energy,and yet the inherently low thermal conductivity buried oxide layer severely impedes thermal management in SOI-based radio frequency/power devices.While diamond offers exceptional thermal conductivity to enhance heat dissipation,its significant thermomechanical mismatch with silicon poses major challenges to reliable hetero-integration.Here we demonstrate a novel silicon film-on-diamond(SOD)heterostructure using microtransfer printing(μTP)technology,with comparative analysis against surface activated bonded silicon-on-silicon carbide(SOC)and conventional SOI wafers.TheμTP-SOD samples exhibit near-zero residual stress(0.026 GPa)in the transferred Si layer and substantially reduced interfacial thermal resistance(ITR)compared to conventional SOI and SOC wafers.Integrated analysis of interfacial microstructures and molecular dynamics simulations reveals how interfacial structures and amorphous compositions govern the phonon thermal transport.Particularly,the amorphous SiO-SiC transition layer enhances phonon transmission at theμTP-SOD heterointerface to achieve a low ITR of 6.3+1.6/-1.5 m^(2)·K/GW.Finite element analysis verifies that these interfacial enhancements,combined with the diamond’s exceptional thermal conductivity,reduce the device junction-temperature rise by 66.7%relative to SOI devices at 15 W/mm output power.The low residual stress and reduced ITR ofμTP-SOD are expected to provide promising thermal management schemes for SOI-based electronics.展开更多
基金This work is supported by Demonstration of Scientific and Technology Achievements Transform in Sichuan Province under Grant 2022ZHCG0036National Natural Science Foundation of China(62002047).
文摘Identifying a device and detecting a change in its position is critical for secure devices management in the Internet of Things(IoT).In this paper,a device management system is proposed to track the devices by using audio-based location distinction techniques.In the proposed scheme,traditional cryptographic techniques,such as symmetric encryption algorithm,RSA-based signcryption scheme,and audio-based secure transmission,are utilized to provide authentication,non-repudiation,and confidentiality in the information interaction of the management system.Moreover,an audio-based location distinction method is designed to detect the position change of the devices.Specifically,the audio frequency response(AFR)of several frequency points is utilized as a device signature.The device signature has the features as follows.(1)Hardware Signature:different pairs of speaker and microphone have different signatures;(2)Distance Signature:in the same direction,the signatures are different at different distances;and(3)Direction Signature:at the same distance,the signatures are different in different directions.Based on the features above,amovement detection algorithmfor device identification and location distinction is designed.Moreover,a secure communication protocol is also proposed by using traditional cryptographic techniques to provide integrity,authentication,and non-repudiation in the process of information interaction between devices,Access Points(APs),and Severs.Extensive experiments are conducted to evaluate the performance of the proposed method.The experimental results show that the proposedmethod has a good performance in accuracy and energy consumption.
基金financially supported by the National Natural Science Foundation of China(Nos.52327802,52130303 and 52173078)the National Key R&D Program of China(No.2022YFB3805702)+1 种基金Joint Funds of Ministry of Education(No.8091B022225)Tianjin University Science and Technology Leading Cultivation Program“Qiming Plan”(No.2023XQM-0048).
文摘In the context of 5G,the high-frequency cyclicity and inhomogeneity of heat flow put forward higher requirements for the thermal control system of electronic devices,and there is a great need for thermal management modules with fixed point and high efficiency to ensure the long-term development of electronic devices.Here,we selected four phase change molecules with significant differences in phase change temperatures to be composited with graphene aerogel(GA)to obtain Ei@GA,Tetra@GA,Octa@GA,and 1,10-Deca@GA.Compared with pure phase change molecules,the thermal conductivity has been increased by more than 20%,and the relative enthalpic efficiency is as high as 98.7%or more.Further,we assembled the four phase change composites by“reduction welding”to obtain the integrated,modular thermal management device M1-PCMs@GA.Simulation of inhomogeneous heat generation in electronics by building an inhomogeneous heat generation platform.Compared with the homogeneous modules M2-Ei@GA and M3-1,10-Deca@GA,the effective temperature control time of the customized module M1-PCMs@GA is extended by 100.0 and 394.3 s,respectively.Therefore,custom-assembled modular thermal management devices have important application prospects in the field of intelligent temperature control of electronic devices,and the idea of cascade assembly enriches the application functions and development direction of intelligent thermal managers.
文摘With the expansion of the scale of our hospital robot laboratory, equipment use, reserves are increasing, manual management equipment information has been unable to adapt to daily management, such as data record error rate increased, the number of experiments increased, equipment loss and maintenance is not clearly defined. In order to ensure the safety and accuracy of the equipment, a system of equipment management systems was developed as a result of the conversion to the use of management systems for the recording and storage of information. The design of this system is a perfect robot laboratory equipment management system based on the development of web framework technology for equipment management functions. The back end of this system uses the Java language, the SSM framework as the main body, the database is built by MySQL relational database, the front-end page uses JSP, Bootstrap, jQuery and other technologies, and uses Eclipse project construction tools for system development. After a period of trial operation, the level of laboratory equipment management has been significantly improved.
基金supported by Hefei Advanced Light Facility(HALF),a major national science and technology infrastructure in China.
文摘Purpose The control network is a critical infrastructure that supports the stable operation of the accelerator.Each device accessing the control network has different device information,such as IP address,MAC address,connected switches and ports,device location and purpose.Accurately maintaining the mapping relationship between these device information facilitates network management.It helps inventory assets,fault location and provide visibility into dynamic changes of device on the network.However,existing tools cannot fully satisfy these demands.They only map some information and lack details important for accelerator facilities like device location and purpose.Additionally,they only reflect the current status rather than indicating dynamic changes across all devices over time.As intelligent devices proliferate,the scale of the control network is rapidly expanding,posing greater challenges in maintaining mapping relationships.Methods This paper proposes a device information-centered Accelerator Control Network Management System(ACNMS).It establishes a device information management framework and allows network administrators to perceive the dynamic changes of devices on the network.The system adopts a layered architecture.Back-end modules implement the core logic of all functions.The graphical user interface presents data and provides a management portal.Results The system test on the control network of the National Synchrotron Radiation Laboratory demonstrates that it can meet the functional design objectives.The application scenarios of the ACNMS are further expanded through system integration and combination with network automation.Conclusion The ACNMS has proven to be an efficient network management tool that significantly improves the operation and maintenance efficiency of the accelerator control network.
基金Supported by the Guangzhou Key Technology R&D Program (No. 2007Z2-D0011)
文摘Java technology is spreading rapidly all over the world in recent years. It is a popular application development language for its well-encapsulation, platform-independent and high security. There are great amounts of Java games and other gadgets on mobile platforms, as well as on set-up-box systems. As Java applications become more sophisticated, the Java Virtual Machine (JVM) mid-dle-wares in embedded systems are not satisfying, Java-specific chips extend in the market. All existing Java-based system software or Operating System (OS) are used on JVM, they cannot be used on Java processors. It is important to develop a pure Java system software or OS so that embedded systems using Java processors will have great performance in Java applications. This paper presents a set of system software designed for a Java-specified processor VP6K, which is also a System-on-Chip (SoC). This system software includes real-time multitask dispatching, file management, device management, hardware drivers, and infrastructural Application Programming Interface (APIs). According to ex-perimental results, the system software provides interfaces for Java programs to fully handle CPU resource, so that all applications can be executed properly and efficiently. VP6K embedded platform shows its good performance for Java applications when the system software is implemented.
基金supported by the National Natural Science Foundation of China (Grant No. 50975280)the Program for New Century Excellent Talents in University of Ministry of Education of China (Grant No. NCET-08-0149)
文摘The interior comer flow theory is fundamental for liquid management in space. In this paper, the interior comer flow theory is modified by correction of the curvature and shape parameters based on geometry relationship, so that it can be extended to a wide range of applications including different dihedral angles and contact angles. This modification is validated with the data provided by the references using capillary tube and drop tower. Besides, the errors between the theory and experiment value are analyzed for the case of small viscosity and the long-time flow, finding that the main reason causing the error is the transformation of the flow resistance along the flow path. At last, the theory of interior comer flow is applied to the primary design of the Propellant Management Device in satellite tank, and optimum design of the vanes is given in terms of maximum flow rate.
文摘The aim of this paper is to present a new topology of a DC-DC power converter for conditioning the current and voltages behaviors of embarked energy sources used in electrical vehicles. The fuel cells in conjunction with ultra-capacitors have been chosen as the power supply. The originality of the proposed converter is to use a variable voltage of the DC bus of the vehicle. The goal is to allow a better energy management of the embedded sources onboard the vehicle by improving its energy efficiency. After presenting and explaining the topology of the converter, some simulation and experiments results are shown to highlight its different operation modes.
基金This workis supported by National Natural Science Foundation of China(60372098) .
文摘Recently, Terminal has become one of the key issues in the 3G development. In the paper, we study the mobile terminal management in 3G network. Based on the analysis of problems encountered with the terminals, the paper describes the use cases of terminal management. A system architecture with its function components of mobile terminal management system is proposed. Moreover, a possible implementation solution is introduced and described. A Management Information Model （MIM） for terminal management is also proposed to support the management services.
基金supported by the National Key R&D Program of China(No.2023YFA1407001)the National Natural Science Foundation of China(Nos.11975125,12204472,and 62304232)+1 种基金the Guangdong Special Support Program(No.2021TQ06C953)the Open Research Fund of State Key Laboratory of Materials for Integrated Circuits(No.SKLIC-K2024-04).
文摘The superior radiation tolerance of silicon-on-insulator(SOI)wafers makes them critical for next-generation integrated circuit and micro-electro-mechanical system electronics in space technology and nuclear energy,and yet the inherently low thermal conductivity buried oxide layer severely impedes thermal management in SOI-based radio frequency/power devices.While diamond offers exceptional thermal conductivity to enhance heat dissipation,its significant thermomechanical mismatch with silicon poses major challenges to reliable hetero-integration.Here we demonstrate a novel silicon film-on-diamond(SOD)heterostructure using microtransfer printing(μTP)technology,with comparative analysis against surface activated bonded silicon-on-silicon carbide(SOC)and conventional SOI wafers.TheμTP-SOD samples exhibit near-zero residual stress(0.026 GPa)in the transferred Si layer and substantially reduced interfacial thermal resistance(ITR)compared to conventional SOI and SOC wafers.Integrated analysis of interfacial microstructures and molecular dynamics simulations reveals how interfacial structures and amorphous compositions govern the phonon thermal transport.Particularly,the amorphous SiO-SiC transition layer enhances phonon transmission at theμTP-SOD heterointerface to achieve a low ITR of 6.3+1.6/-1.5 m^(2)·K/GW.Finite element analysis verifies that these interfacial enhancements,combined with the diamond’s exceptional thermal conductivity,reduce the device junction-temperature rise by 66.7%relative to SOI devices at 15 W/mm output power.The low residual stress and reduced ITR ofμTP-SOD are expected to provide promising thermal management schemes for SOI-based electronics.
