With the rapid expansion of e-commerce,its security and risk management problems become increasingly prominent.In the current business environment,the ability to understand and apply e-commerce security and risk manag...With the rapid expansion of e-commerce,its security and risk management problems become increasingly prominent.In the current business environment,the ability to understand and apply e-commerce security and risk management has become an important criterion to measure a good person.Therefore,the importance of e-commerce security and risk management courses in college education is self-evident.This course can not only help students master the basic knowledge of e-commerce,but also enable them to understand how to deal with various risks in practical work and ensure the safe operation of e-commerce.At the same time,through the study of e-commerce security and risk management,students can better understand the operation mode and law of e-commerce,and lay a solid foundation for their future career.In general,e-commerce security and risk management occupy an important position in the curriculum of colleges and universities,and play a crucial role in cultivating e-commerce professionals with practical operation ability and innovative thinking.展开更多
To further enhance the overall service quality of China’s hospitals and improve the trust of the majority of patients in hospitals,this paper takes intelligent hospital management as the object of study,analyzes the ...To further enhance the overall service quality of China’s hospitals and improve the trust of the majority of patients in hospitals,this paper takes intelligent hospital management as the object of study,analyzes the importance of electronic information engineering technology applied in hospital management,and discusses the specific application methods of electronic information engineering in hospital management.This aims the existing problems in the current hospital management,such as insufficient degree of informatization,data sharing difficulties,lack of professionals,etc.Corresponding improvement measures are proposed,including strengthening the construction of informatization,promoting data sharing,and cultivating professionals.It is hoped that this study will enable the majority of hospital managers to make better use of electronic information engineering technology to effectively solve the current problems faced by hospitals and to continuously improve the comprehensive competitiveness of China’s hospitals.展开更多
The heat generation of electronic devices is increasing dramatically,which causes a serious bottleneck in the thermal management of electronics,and overheating will result in performance deterioration and even device ...The heat generation of electronic devices is increasing dramatically,which causes a serious bottleneck in the thermal management of electronics,and overheating will result in performance deterioration and even device damage.With the development of micro-machining technologies,the microchannel heat sink(MCHS)has become one of the best ways to remove the considerable amount of heat generated by high-power electronics.It has the advantages of large specific surface area,small size,coolant saving and high heat transfer coefficient.This paper comprehensively takes an overview of the research progress in MCHSs and generalizes the hotspots and bottlenecks of this area.The heat transfer mechanisms and performances of different channel structures,coolants,channel materials and some other influencing factors are reviewed.Additionally,this paper classifies the heat transfer enhancement technology and reviews the related studies on both the single-phase and phase-change flow and heat transfer.The comprehensive review is expected to provide a theoretical reference and technical guidance for further research and application of MCHSs in the future.展开更多
The power density of electronic components grows continuously,and the subsequent heat accumulation and temperature increase inevitably affect electronic equipment’s stability,reliability and service life.Therefore,ac...The power density of electronic components grows continuously,and the subsequent heat accumulation and temperature increase inevitably affect electronic equipment’s stability,reliability and service life.Therefore,achieving efficient cooling in limited space has become a key problem in updating electronic devices with high performance and high integration.Two-phase immersion is a novel cooling method.The computational fluid dynamics(CFD)method is used to investigate the cooling performance of two-phase immersion cooling on high-power electronics.The two-dimensional CFD model is utilized by the volume of fluid(VOF)method and Reynolds StressModel.Lee’s model was employed to calculate the phase change rate.The heat transfer coefficient along the heatedwalls and the shear-lift force on bubbles are calculated.The simulation data are verified with the literature results.The cooling performance of different coolants has been studied.The results indicate that the boiling heat transfer coefficient can be enhanced by using a low boiling point coolant.The methanol is used as the cooling medium for further research.In addition,the mass flow rate and inlet temperature are investigated to assess the thermal performance of twophase immersion cooling.The average temperature of the high-power electronics is 80℃,and the temperature difference can be constrained to 8℃.Meanwhile,the convective heat transfer coefficient reaches 2740 W/(m2・℃)when the inlet temperature is 50℃,and the mass flow rate is 0.3 kg/s.In conclusion,the results demonstrated that two-phase immersion cooling has provided an effective method for the thermal management of high-power electronics.展开更多
Digestive endoscopy is currently the main diagnostic procedure for investigation of the digestive tract when a digestive disease is suspected.The use of computers and electronic medical records for the management of e...Digestive endoscopy is currently the main diagnostic procedure for investigation of the digestive tract when a digestive disease is suspected.The use of computers and electronic medical records for the management of endoscopic data are an important key to improving endoscopy unit efficiency and productivity.This technology supports optimal program operation,monitoring and evaluation colorectal cancer screening.This article is a comprehensive survey of endoscopic electronic medical records and information systems.Computerized clinical records have the capability of identifying patients due for screening and to calculate baseline rates of colorectal cancer screening by patient characteristics and by primary care physician and practice group.This paper describes data flow in the endoscopy unit,the minimum data set of colorectal cancer and key features of endoscopic electronic medical record.In addition,the researchers state standards in different aspects,especially terminology standards and interoperability standards for image and text.展开更多
At present, all aspects of China have entered the era of a rapid development, while the development speed of digital electronic technology is especially outstanding. This is a new way for China＇ s new personnel train...At present, all aspects of China have entered the era of a rapid development, while the development speed of digital electronic technology is especially outstanding. This is a new way for China＇ s new personnel training, and also proposes higher requirements on this type of personnel training institutions. In view of the demands of society and different majors on personnel, an enhancement to the standardized management of electronic laboratory operations becomes one of the important tasks for personnel training institutions. In this paper, how to practice the standardization management in an all-round way is discussed centered at college and university students＇ electronic laboratory.展开更多
In order to better promote the digital and electronic development of libraries,this paper first analyzes the management requirements of library archives,constructs a management mode based on electronic technology,and ...In order to better promote the digital and electronic development of libraries,this paper first analyzes the management requirements of library archives,constructs a management mode based on electronic technology,and analyzes the management measures of electronic library archives for reference.展开更多
Two-dimensional elec tronic spec troscopy(2DES)is a powerful met hod to probe the coherent electron dynamics in complicated systems.Stabilizing the phase difference of the incident ultrashort pulses is the mos t chall...Two-dimensional elec tronic spec troscopy(2DES)is a powerful met hod to probe the coherent electron dynamics in complicated systems.Stabilizing the phase difference of the incident ultrashort pulses is the mos t challenging par t for experimen tal demonstration of 2DES.Here,we present a tuto rial review on the 2DES proto cols based on active phase managements which are originally developed for quantum optics experiments.We introduce the 2DES techniques in box and pump-probe geometries with phase stabilization realized by interferometry,and outline the fully collinear 2DES approach with the frequency tagging by acoustic optical modulators and frequency combs.The combination of active phase managements,ultrashort pulses and other spectroscopic methods may open new opportunities to tackle essential challenges related to excited states.展开更多
With the development of information technology,cloud computing technology has brought many conveniences to all aspects of work and life.With the continuous promotion,popularization and vigorous development of e-govern...With the development of information technology,cloud computing technology has brought many conveniences to all aspects of work and life.With the continuous promotion,popularization and vigorous development of e-government and e-commerce,the number of documents in electronic form is getting larger and larger.Electronic document is an indispensable main tool and real record of e-government and business activities.How to scientifically and effectively manage electronic documents?This is an important issue faced by governments and enterprises in improving management efficiency,protecting state secrets or business secrets,and reducing management costs.This paper discusses the application of cloud computing technology in the construction of electronic file management system,proposes an architecture of electronic file management system based on cloud computing,and makes a more detailed discussion on key technologies and implementation.The electronic file management system is built on the cloud architecture to enable users to upload,download,share,set security roles,audit,and retrieve files based on multiple modes.An electronic file management system based on cloud computing can make full use of cloud storage,cloud security,and cloud computing technologies to achieve unified,reliable,and secure management of electronic files.展开更多
This study investigates the status of e-SCM and performance among Jordanian manufacturing sector. The objective of this study is to analyze the impact of trust and communication on the e-SCM usage. Moreover, the study...This study investigates the status of e-SCM and performance among Jordanian manufacturing sector. The objective of this study is to analyze the impact of trust and communication on the e-SCM usage. Moreover, the study investigates the effect of the trust and communication on the firm’s performance while the e-SCM usage is used as a mediating factor on firm’s performance. The proposed research model was validated by distributing 250 survey questionnaires to the manufacturing sector in Jordan. Structural equation modelling (SEM) technique was used to analyze the results. One of the main limitations of this study was that the results could not be universal since the study was limited to Jordan. We discussed the implications of our results for research and practice.展开更多
Many libraries have built and opened the electronic reading room,electronic reading room security management has been paid more and more attention.In the specific safety management,the prevention and control of reader...Many libraries have built and opened the electronic reading room,electronic reading room security management has been paid more and more attention.In the specific safety management,the prevention and control of reader factors is very important.By comparing and analyzing the prevention and control of reader factors in the safety management of some electronic reading rooms,it can be found that the corresponding prevention and control situation is not ideal,and even there are some obvious problems,which also leads to great hidden dangers in the safety management level.This paper will specifically analyze the prevention and control of reader factors in the safety management of electronic reading room,and put forward more effective prevention and control strategies.展开更多
The purpose of introducing blockchain into electronic archives sharing and utilization is to break the information barrier between electronic archives sharing departments by relying on technologies such as smart contr...The purpose of introducing blockchain into electronic archives sharing and utilization is to break the information barrier between electronic archives sharing departments by relying on technologies such as smart contract and asymmetric encryption.Aiming at the problem of dynamic permission management in common access control methods,a new access control method based on smart contract under blockchain is proposed,which improves the intelligence level under blockchain technology.Firstly,the Internet attribute access control model based on smart contract is established.For the dynamic access of heterogeneous devices,the management contract,permission judgment contract and access control contract are designed;Secondly,the access object credit evaluation algorithm based on particle swarm optimization radial basis function(PSO-RBF)neural network is used to dynamically generate the access node credit threshold combined with the access policy,so as to realize the intelligent access right management method.Finally,combined with the abovemodels and algorithms,the workflow of electronic archives sharing and utilization model of multi blockchain is constructed.The experimental results show that the timeconsuming of the process increases linearly with the number of continuous access to electronic archives blocks,and the secure access control of sharing and utilization is feasible,secure and effective.展开更多
The exponentially increasing heat generation in electronic devices,induced by high power density and miniaturization,has become a dominant issue that affects carbon footprint,cost,performance,reliability,and lifespan....The exponentially increasing heat generation in electronic devices,induced by high power density and miniaturization,has become a dominant issue that affects carbon footprint,cost,performance,reliability,and lifespan.Liquid metals(LMs)with high thermal conductivity are promising candidates for effective thermal management yet are facing pump-out and surface-spreading issues.Confinement in the form of metallic particles can address these problems,but apparent alloying processes elevate the LM melting point,leading to severely deteriorated stability.Here,we propose a facile and sustainable approach to address these challenges by using a biogenic supramolecular network as an effective diffusion barrier at copper particle-LM(EGaIn/Cu@TA)interfaces to achieve superior thermal conduction.The supramolecular network promotes LM stability by reducing unfavorable alloying and fluidity transition.The EGaIn/Cu@TA exhibits a record-high metallic-mediated thermal conductivity(66.1 W m^(-1) K^(-1))and fluidic stability.Moreover,mechanistic studies suggest the enhanced heat flow path after the incorporation of copper particles,generating heat dissipation suitable for computer central processing units,exceeding that of commercial silicone.Our results highlight the prospects of renewable macromolecules isolated from biomass for the rational design of nanointerfaces based on metallic particles and LM,paving a new and sustainable avenue for high-performance thermal management.展开更多
Due to the rapid development of the space industry,ever higher demands are being made for the optimization and improvement of spacecraft thermal management systems.Thermal control technology has become one of the key ...Due to the rapid development of the space industry,ever higher demands are being made for the optimization and improvement of spacecraft thermal management systems.Thermal control technology has become one of the key bottlenecks that restrict the level of spacecraft design.In this paper,the thermal management technologies(TMTs)for spacecraft electronics are reviewed according to the different heat transfer processes,including heat acquisition,heat transport,and heat rejection.The researches on efficient heat acquisition include the utilization of high thermal conductance materials,the development of novel package structure based on micro-/nanoelectromechanical system(MEMS/NEMS)technologies,and advanced near-junction microfluidic cooling techniques.For the heat transport process,various heat pipes and mechanical pumped fluid loops(MPFLs)are widely implemented to transport heat from heat generation components to the ultimate heat sinks.The heat pipes are divided into two categories based on their structure layout,i.e.,separated heat pipes and unseparated heat pipes.The merits and demerits of these heat pipes and MPFLs(including the single-phase MPFL and the two-phase MPFL)are discussed and summarized respectively.In terms of the heat rejection for spacecraft,thermal radiators are normally the sole option due to the unique space environment.To meet the requirements of large heat dissipation power and fluctuated thermal environment,research efforts on the radiators mainly focus on the development of deployable radiators,variable emissivity radiators,and the combination with other techniques.Due to the fluctuated characteristics of the heat power of internal electronics and the outer thermal environment,the phase change materials(PCMs)exhibit great advantages in this scenario and have attracted a lot of research attention.This review aims to serve as a reference guide for the development of thermal management system in the future spacecraft.展开更多
This paper proposes a useful web-based system for the management and sharing of electron probe micro-analysis( EPMA)data in geology. A new web-based architecture that integrates the management and sharing functions is...This paper proposes a useful web-based system for the management and sharing of electron probe micro-analysis( EPMA)data in geology. A new web-based architecture that integrates the management and sharing functions is developed and implemented.Earth scientists can utilize this system to not only manage their data,but also easily communicate and share it with other researchers.Data query methods provide the core functionality of the proposed management and sharing modules. The modules in this system have been developed using cloud GIS technologies,which help achieve real-time spatial area retrieval on a map. The system has been tested by approximately 263 users at Jilin University and Beijing SHRIMP Center. A survey was conducted among these users to estimate the usability of the primary functions of the system,and the assessment result is summarized and presented.展开更多
The construction of advanced laboratories for precision instruments, such as electron microscopes, involves unique challenges that are influenced by the specific environmental conditions required for optimal functiona...The construction of advanced laboratories for precision instruments, such as electron microscopes, involves unique challenges that are influenced by the specific environmental conditions required for optimal functionality. These include mitigating interference from magnetic fields and vibrations, which are critical for maintaining the precision and accuracy of the instruments used. This study aims to offer enhanced project management strategies and detailed construction solutions that address the environmental and technical needs specific to electron microscopy labs, thereby facilitating effective lab operations and extending the lifecycle of high-end precision instruments. Case studies of existing laboratory constructions, onsite investigations, and comprehensive reviews of the technical and environmental requirements provide the basis for a best practice for constructing sophisticated electron microscopy labs. The approach integrates both pre-construction planning and post-construction adjustments to create optimal operational environments. The findings suggest that successful lab constructions are those that incorporate thorough onsite assessments, strategic location choices, and the use of advanced construction materials and techniques specifically designed to counteract environmental challenges like magnetic and vibration interferences. Actionable guidelines for both planning and executing the construction of electron microscope labs highlighted in this tutorial are intended as an important resource to troubleshoot or upgrade existing lab facilities and to consult in preparation of future lab construction projects.展开更多
High performance can be obtained for the integrated power electronics module（IPEM） by using a three-dimensional packaging structure instead of a planar structure. A three- dimensional packaged half bridge-IPEM （HB-...High performance can be obtained for the integrated power electronics module（IPEM） by using a three-dimensional packaging structure instead of a planar structure. A three- dimensional packaged half bridge-IPEM （HB-IPEM）, consisting of two chip scale packaged MOSFETs and the corresponding gate driver and protection circuits, is fabricated at the laboratory. The reliability of the IPEM is controlled from the shape design of solder joints and the control of assembly process parameters. The parasitic parameters are extracted using Agilent 4395A impedance analyzer for building the parasitic parameter model of the HB- IPEM. A 12 V/3 A output synchronous rectifier Buck converter using the HB-IPEM is built to test the electrical performance of the HB-IPEM. Low voltage spikes on two MOSFETs illustrate that the three-dimensional package of the HB-IPEM can decrease parasitic inductance. Temperature distribution simulation results of the HB-IPEM using FLOTHERM are given. Heat dissipation of the solder joints makes the peak junction temperature of the chip drop obviously. The package realizes three-dimensional heat dissipation and has better thermal management.展开更多
Aim To study the diesel engine management spstem (DEMS). The DEMS can consider many engine parameters and so it can acquire the optimum system performance. Methods On the basis of analyzing the characteristics of die...Aim To study the diesel engine management spstem (DEMS). The DEMS can consider many engine parameters and so it can acquire the optimum system performance. Methods On the basis of analyzing the characteristics of diesel engine electronic system, the real-time, multi-tasks system design methods were used for the heavy duty vehicular diesel engine electronic control system . The hardware and software of DEMS were developed. Results and Conalusion By the test on dieSel engine bed, the system was verified and the foundation of the fully developed DEMS was laid.展开更多
文摘With the rapid expansion of e-commerce,its security and risk management problems become increasingly prominent.In the current business environment,the ability to understand and apply e-commerce security and risk management has become an important criterion to measure a good person.Therefore,the importance of e-commerce security and risk management courses in college education is self-evident.This course can not only help students master the basic knowledge of e-commerce,but also enable them to understand how to deal with various risks in practical work and ensure the safe operation of e-commerce.At the same time,through the study of e-commerce security and risk management,students can better understand the operation mode and law of e-commerce,and lay a solid foundation for their future career.In general,e-commerce security and risk management occupy an important position in the curriculum of colleges and universities,and play a crucial role in cultivating e-commerce professionals with practical operation ability and innovative thinking.
文摘To further enhance the overall service quality of China’s hospitals and improve the trust of the majority of patients in hospitals,this paper takes intelligent hospital management as the object of study,analyzes the importance of electronic information engineering technology applied in hospital management,and discusses the specific application methods of electronic information engineering in hospital management.This aims the existing problems in the current hospital management,such as insufficient degree of informatization,data sharing difficulties,lack of professionals,etc.Corresponding improvement measures are proposed,including strengthening the construction of informatization,promoting data sharing,and cultivating professionals.It is hoped that this study will enable the majority of hospital managers to make better use of electronic information engineering technology to effectively solve the current problems faced by hospitals and to continuously improve the comprehensive competitiveness of China’s hospitals.
基金supported by the National Natural Science Foundation of China(Grant Nos.U20A20301,51825601)。
文摘The heat generation of electronic devices is increasing dramatically,which causes a serious bottleneck in the thermal management of electronics,and overheating will result in performance deterioration and even device damage.With the development of micro-machining technologies,the microchannel heat sink(MCHS)has become one of the best ways to remove the considerable amount of heat generated by high-power electronics.It has the advantages of large specific surface area,small size,coolant saving and high heat transfer coefficient.This paper comprehensively takes an overview of the research progress in MCHSs and generalizes the hotspots and bottlenecks of this area.The heat transfer mechanisms and performances of different channel structures,coolants,channel materials and some other influencing factors are reviewed.Additionally,this paper classifies the heat transfer enhancement technology and reviews the related studies on both the single-phase and phase-change flow and heat transfer.The comprehensive review is expected to provide a theoretical reference and technical guidance for further research and application of MCHSs in the future.
基金support from the Key Laboratory of Multiphase Flow Reaction and Separation Engineering of Shandong Province,China(Grant No.2021MFRSE-C01)the Natural Science Foundation of Gansu Province,China(No.22JR5RA269)Fujian Province Science Foundation for Youths,China(No.2020305069).
文摘The power density of electronic components grows continuously,and the subsequent heat accumulation and temperature increase inevitably affect electronic equipment’s stability,reliability and service life.Therefore,achieving efficient cooling in limited space has become a key problem in updating electronic devices with high performance and high integration.Two-phase immersion is a novel cooling method.The computational fluid dynamics(CFD)method is used to investigate the cooling performance of two-phase immersion cooling on high-power electronics.The two-dimensional CFD model is utilized by the volume of fluid(VOF)method and Reynolds StressModel.Lee’s model was employed to calculate the phase change rate.The heat transfer coefficient along the heatedwalls and the shear-lift force on bubbles are calculated.The simulation data are verified with the literature results.The cooling performance of different coolants has been studied.The results indicate that the boiling heat transfer coefficient can be enhanced by using a low boiling point coolant.The methanol is used as the cooling medium for further research.In addition,the mass flow rate and inlet temperature are investigated to assess the thermal performance of twophase immersion cooling.The average temperature of the high-power electronics is 80℃,and the temperature difference can be constrained to 8℃.Meanwhile,the convective heat transfer coefficient reaches 2740 W/(m2・℃)when the inlet temperature is 50℃,and the mass flow rate is 0.3 kg/s.In conclusion,the results demonstrated that two-phase immersion cooling has provided an effective method for the thermal management of high-power electronics.
文摘Digestive endoscopy is currently the main diagnostic procedure for investigation of the digestive tract when a digestive disease is suspected.The use of computers and electronic medical records for the management of endoscopic data are an important key to improving endoscopy unit efficiency and productivity.This technology supports optimal program operation,monitoring and evaluation colorectal cancer screening.This article is a comprehensive survey of endoscopic electronic medical records and information systems.Computerized clinical records have the capability of identifying patients due for screening and to calculate baseline rates of colorectal cancer screening by patient characteristics and by primary care physician and practice group.This paper describes data flow in the endoscopy unit,the minimum data set of colorectal cancer and key features of endoscopic electronic medical record.In addition,the researchers state standards in different aspects,especially terminology standards and interoperability standards for image and text.
文摘At present, all aspects of China have entered the era of a rapid development, while the development speed of digital electronic technology is especially outstanding. This is a new way for China＇ s new personnel training, and also proposes higher requirements on this type of personnel training institutions. In view of the demands of society and different majors on personnel, an enhancement to the standardized management of electronic laboratory operations becomes one of the important tasks for personnel training institutions. In this paper, how to practice the standardization management in an all-round way is discussed centered at college and university students＇ electronic laboratory.
文摘In order to better promote the digital and electronic development of libraries,this paper first analyzes the management requirements of library archives,constructs a management mode based on electronic technology,and analyzes the management measures of electronic library archives for reference.
基金This work is supported by the National Key R&D Program of China(No.2017YFA0303700 and No.2018YFA0209101)the National Natural Science Foundation of China(No.21922302,No.21873047,No.11904168,No.91833305,and No.91850105)+1 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe Fundamental Research Funds for the Central University.
文摘Two-dimensional elec tronic spec troscopy(2DES)is a powerful met hod to probe the coherent electron dynamics in complicated systems.Stabilizing the phase difference of the incident ultrashort pulses is the mos t challenging par t for experimen tal demonstration of 2DES.Here,we present a tuto rial review on the 2DES proto cols based on active phase managements which are originally developed for quantum optics experiments.We introduce the 2DES techniques in box and pump-probe geometries with phase stabilization realized by interferometry,and outline the fully collinear 2DES approach with the frequency tagging by acoustic optical modulators and frequency combs.The combination of active phase managements,ultrashort pulses and other spectroscopic methods may open new opportunities to tackle essential challenges related to excited states.
基金research Grants from the National Social Science Foundation of China(Grant No.18FTQ005).The author of the grant is Shi Jin.The URL of the sponsor site is http://www.npopss-cn.gov.cn/.
文摘With the development of information technology,cloud computing technology has brought many conveniences to all aspects of work and life.With the continuous promotion,popularization and vigorous development of e-government and e-commerce,the number of documents in electronic form is getting larger and larger.Electronic document is an indispensable main tool and real record of e-government and business activities.How to scientifically and effectively manage electronic documents?This is an important issue faced by governments and enterprises in improving management efficiency,protecting state secrets or business secrets,and reducing management costs.This paper discusses the application of cloud computing technology in the construction of electronic file management system,proposes an architecture of electronic file management system based on cloud computing,and makes a more detailed discussion on key technologies and implementation.The electronic file management system is built on the cloud architecture to enable users to upload,download,share,set security roles,audit,and retrieve files based on multiple modes.An electronic file management system based on cloud computing can make full use of cloud storage,cloud security,and cloud computing technologies to achieve unified,reliable,and secure management of electronic files.
文摘This study investigates the status of e-SCM and performance among Jordanian manufacturing sector. The objective of this study is to analyze the impact of trust and communication on the e-SCM usage. Moreover, the study investigates the effect of the trust and communication on the firm’s performance while the e-SCM usage is used as a mediating factor on firm’s performance. The proposed research model was validated by distributing 250 survey questionnaires to the manufacturing sector in Jordan. Structural equation modelling (SEM) technique was used to analyze the results. One of the main limitations of this study was that the results could not be universal since the study was limited to Jordan. We discussed the implications of our results for research and practice.
文摘Many libraries have built and opened the electronic reading room,electronic reading room security management has been paid more and more attention.In the specific safety management,the prevention and control of reader factors is very important.By comparing and analyzing the prevention and control of reader factors in the safety management of some electronic reading rooms,it can be found that the corresponding prevention and control situation is not ideal,and even there are some obvious problems,which also leads to great hidden dangers in the safety management level.This paper will specifically analyze the prevention and control of reader factors in the safety management of electronic reading room,and put forward more effective prevention and control strategies.
基金supported by Shandong Social Science Planning and Research Project in 2021(No.21CPYJ40).
文摘The purpose of introducing blockchain into electronic archives sharing and utilization is to break the information barrier between electronic archives sharing departments by relying on technologies such as smart contract and asymmetric encryption.Aiming at the problem of dynamic permission management in common access control methods,a new access control method based on smart contract under blockchain is proposed,which improves the intelligence level under blockchain technology.Firstly,the Internet attribute access control model based on smart contract is established.For the dynamic access of heterogeneous devices,the management contract,permission judgment contract and access control contract are designed;Secondly,the access object credit evaluation algorithm based on particle swarm optimization radial basis function(PSO-RBF)neural network is used to dynamically generate the access node credit threshold combined with the access policy,so as to realize the intelligent access right management method.Finally,combined with the abovemodels and algorithms,the workflow of electronic archives sharing and utilization model of multi blockchain is constructed.The experimental results show that the timeconsuming of the process increases linearly with the number of continuous access to electronic archives blocks,and the secure access control of sharing and utilization is feasible,secure and effective.
基金National Talents ProgramNational Natural Science Foundation of China,Grant/Award Numbers:22108181,22178233+4 种基金Talents Program of Sichuan ProvinceDouble First-Class University Plan of Sichuan UniversityState Key Laboratory of Polymer Materials Engineering,Grant/Award Number:sklpme 2020-03-01Sichuan Science and Technology Program,Grant/Award Number:2022YFN0070The Sichuan Province Postdoctoral Special Funding。
文摘The exponentially increasing heat generation in electronic devices,induced by high power density and miniaturization,has become a dominant issue that affects carbon footprint,cost,performance,reliability,and lifespan.Liquid metals(LMs)with high thermal conductivity are promising candidates for effective thermal management yet are facing pump-out and surface-spreading issues.Confinement in the form of metallic particles can address these problems,but apparent alloying processes elevate the LM melting point,leading to severely deteriorated stability.Here,we propose a facile and sustainable approach to address these challenges by using a biogenic supramolecular network as an effective diffusion barrier at copper particle-LM(EGaIn/Cu@TA)interfaces to achieve superior thermal conduction.The supramolecular network promotes LM stability by reducing unfavorable alloying and fluidity transition.The EGaIn/Cu@TA exhibits a record-high metallic-mediated thermal conductivity(66.1 W m^(-1) K^(-1))and fluidic stability.Moreover,mechanistic studies suggest the enhanced heat flow path after the incorporation of copper particles,generating heat dissipation suitable for computer central processing units,exceeding that of commercial silicone.Our results highlight the prospects of renewable macromolecules isolated from biomass for the rational design of nanointerfaces based on metallic particles and LM,paving a new and sustainable avenue for high-performance thermal management.
基金National Science Foundation of China(Grant No.:52206113)Science Fund Program for Distinguished Young Scholars(Overseas)(Grant No.:GYKP020).
文摘Due to the rapid development of the space industry,ever higher demands are being made for the optimization and improvement of spacecraft thermal management systems.Thermal control technology has become one of the key bottlenecks that restrict the level of spacecraft design.In this paper,the thermal management technologies(TMTs)for spacecraft electronics are reviewed according to the different heat transfer processes,including heat acquisition,heat transport,and heat rejection.The researches on efficient heat acquisition include the utilization of high thermal conductance materials,the development of novel package structure based on micro-/nanoelectromechanical system(MEMS/NEMS)technologies,and advanced near-junction microfluidic cooling techniques.For the heat transport process,various heat pipes and mechanical pumped fluid loops(MPFLs)are widely implemented to transport heat from heat generation components to the ultimate heat sinks.The heat pipes are divided into two categories based on their structure layout,i.e.,separated heat pipes and unseparated heat pipes.The merits and demerits of these heat pipes and MPFLs(including the single-phase MPFL and the two-phase MPFL)are discussed and summarized respectively.In terms of the heat rejection for spacecraft,thermal radiators are normally the sole option due to the unique space environment.To meet the requirements of large heat dissipation power and fluctuated thermal environment,research efforts on the radiators mainly focus on the development of deployable radiators,variable emissivity radiators,and the combination with other techniques.Due to the fluctuated characteristics of the heat power of internal electronics and the outer thermal environment,the phase change materials(PCMs)exhibit great advantages in this scenario and have attracted a lot of research attention.This review aims to serve as a reference guide for the development of thermal management system in the future spacecraft.
基金National Major Scientific Instruments and Equipment Development Special Funds,China(No.2016YFF0103303)National Science and Technology Support Program,China(No.2014BAK02B03)
文摘This paper proposes a useful web-based system for the management and sharing of electron probe micro-analysis( EPMA)data in geology. A new web-based architecture that integrates the management and sharing functions is developed and implemented.Earth scientists can utilize this system to not only manage their data,but also easily communicate and share it with other researchers.Data query methods provide the core functionality of the proposed management and sharing modules. The modules in this system have been developed using cloud GIS technologies,which help achieve real-time spatial area retrieval on a map. The system has been tested by approximately 263 users at Jilin University and Beijing SHRIMP Center. A survey was conducted among these users to estimate the usability of the primary functions of the system,and the assessment result is summarized and presented.
文摘The construction of advanced laboratories for precision instruments, such as electron microscopes, involves unique challenges that are influenced by the specific environmental conditions required for optimal functionality. These include mitigating interference from magnetic fields and vibrations, which are critical for maintaining the precision and accuracy of the instruments used. This study aims to offer enhanced project management strategies and detailed construction solutions that address the environmental and technical needs specific to electron microscopy labs, thereby facilitating effective lab operations and extending the lifecycle of high-end precision instruments. Case studies of existing laboratory constructions, onsite investigations, and comprehensive reviews of the technical and environmental requirements provide the basis for a best practice for constructing sophisticated electron microscopy labs. The approach integrates both pre-construction planning and post-construction adjustments to create optimal operational environments. The findings suggest that successful lab constructions are those that incorporate thorough onsite assessments, strategic location choices, and the use of advanced construction materials and techniques specifically designed to counteract environmental challenges like magnetic and vibration interferences. Actionable guidelines for both planning and executing the construction of electron microscope labs highlighted in this tutorial are intended as an important resource to troubleshoot or upgrade existing lab facilities and to consult in preparation of future lab construction projects.
基金Fok Ying Tung Education Foundation(No.91058)the Natural Science Foundation of High Education Institutions of Jiangsu Province(No.08KJD470004)Qing Lan Project of Jiangsu Province of 2008
文摘High performance can be obtained for the integrated power electronics module（IPEM） by using a three-dimensional packaging structure instead of a planar structure. A three- dimensional packaged half bridge-IPEM （HB-IPEM）, consisting of two chip scale packaged MOSFETs and the corresponding gate driver and protection circuits, is fabricated at the laboratory. The reliability of the IPEM is controlled from the shape design of solder joints and the control of assembly process parameters. The parasitic parameters are extracted using Agilent 4395A impedance analyzer for building the parasitic parameter model of the HB- IPEM. A 12 V/3 A output synchronous rectifier Buck converter using the HB-IPEM is built to test the electrical performance of the HB-IPEM. Low voltage spikes on two MOSFETs illustrate that the three-dimensional package of the HB-IPEM can decrease parasitic inductance. Temperature distribution simulation results of the HB-IPEM using FLOTHERM are given. Heat dissipation of the solder joints makes the peak junction temperature of the chip drop obviously. The package realizes three-dimensional heat dissipation and has better thermal management.
文摘Aim To study the diesel engine management spstem (DEMS). The DEMS can consider many engine parameters and so it can acquire the optimum system performance. Methods On the basis of analyzing the characteristics of diesel engine electronic system, the real-time, multi-tasks system design methods were used for the heavy duty vehicular diesel engine electronic control system . The hardware and software of DEMS were developed. Results and Conalusion By the test on dieSel engine bed, the system was verified and the foundation of the fully developed DEMS was laid.
