Recently, a statement by the Beijing Administration for Industry and Commerce stopping restaurants and catering services from banning outside beverages has provoked heated debate among the public.
In recent years,interest in banning smartphones in schools has increased.This has become a policy in several US states and municipalities,with other states considering them.The UK continues to debate such policies.Oth...In recent years,interest in banning smartphones in schools has increased.This has become a policy in several US states and municipalities,with other states considering them.The UK continues to debate such policies.Other countries ranging from France to China have also implemented bans on smartphones in schools.However,do such bans work(i.e.,improve grades,mental health,reduce bullying,etc.)?展开更多
随着电力物联网技术的快速发展,建设能源互联网具有重大意义。电力物联终端设备的识别认证是保障能源互联网安全稳定运行的基础。为实现海量电力终端设备信息高效采集与安全认证,研究提出一种面向电力物联网的RFID(radio frequency iden...随着电力物联网技术的快速发展,建设能源互联网具有重大意义。电力物联终端设备的识别认证是保障能源互联网安全稳定运行的基础。为实现海量电力终端设备信息高效采集与安全认证,研究提出一种面向电力物联网的RFID(radio frequency identification)认证方案,该方案利用RFID技术,基于国密SM3和SM4设计算法,实现了阅读器与电力设备之间的相互认证,保障了电力通信数据的传输安全,降低设备标签的计算复杂度。安全性分析表明,该方案满足不可追踪性、抗重放攻击、抗去同步攻击、抗拒绝服务攻击等安全特性,BAN逻辑分析进一步表明该方案满足相互认证性。性能分析表明,该方案在标签计算量、存储量、通信量及数据库搜索效率方面具有较好的性能优势。展开更多
The fossil shells on the sedimentary rocks were collected from The Historical Park,Ban Sap Noi Geopark,Phetchabun Province,Thailand.However,the fossils remained in this area were investigated on the characteristic spe...The fossil shells on the sedimentary rocks were collected from The Historical Park,Ban Sap Noi Geopark,Phetchabun Province,Thailand.However,the fossils remained in this area were investigated on the characteristic species only in geological studies with taxonomy for fossil age predicting.To fill up the gap of these studies,the material characterization techniques were used to study the chemical composition and structure of fossil shells I,II and III.The results clearly showed that the morphologies of all fossil shells were Brachiopod fossils with different species.The functional group and elemental composition of all fossil shells showed that the high content of calcium carbonate was a major composition.In addition,the high content of quartz indicated the silica precipitation phenomenon in all fossil shells.The element composition of cross-sectional morphology and energy dispersive spectroscope (EDS mapping) were used to confirm the presence of Si element in each zone of fossil shells.The crystal structures of all fossil shells were investigated and indicated that the calcium carbonate compound was a calcite phase and silicon dioxide compound was a quartz phase.Moreover,the crystal structure of quartz phase was used to calculate the crystallinity index.The crystallinity index values in all fossil shells indicated a well-crystallized quartz.The age of fossil shells was estimated and found to be brachiopod fossil in carboniferous period with the age of about 359.2 to 299.0 million years.展开更多
该文旨在探讨吐蕃时期连接象雄与胡密国之间的关键交通路线,并深入分析该路线在东西方文化交流与贸易往来中所发挥的重要作用。象雄作为吐蕃西部重镇,凭借其独特地理位置,成为中亚与吐蕃文化交流的重要中转站;胡密国(即敦煌吐蕃藏文文献...该文旨在探讨吐蕃时期连接象雄与胡密国之间的关键交通路线,并深入分析该路线在东西方文化交流与贸易往来中所发挥的重要作用。象雄作为吐蕃西部重镇,凭借其独特地理位置,成为中亚与吐蕃文化交流的重要中转站;胡密国(即敦煌吐蕃藏文文献Or.8212/187中所载“Ban vjag nag bo”),位于今阿富汗巴达赫尚省瓦罕走廊一带,也因其地理优势成为东西文明交汇的重要节点。因此,考察象雄至胡密国的交通路线,对理解吐蕃在中亚地区的战略布局与文化影响具有重要意义。该文综合文献记载与考古研究成果,从以下三方面展开论述:第一,通过分析交通要冲勃律地区的战事,推断吐蕃征服勃律的大致年代,揭示其首次尝试打通中亚通道的战略意图;第二,借助拉达克、巴尔蒂斯坦、吉尔吉特、瓦罕等地现存吐蕃时期藏文石刻的地理分布,勾勒出吐蕃经营该路线的具体路径与年代;第三,结合唐代方志、游记等汉文史料中有关拉达克与瓦罕之间的往来记载,进一步还原该路线的实际运作情况。通过深入探讨该路线的战略意义、运作机制与历史作用,有助于更清晰地认识吐蕃在中亚地区的活动及其对东西方文化交流的贡献。展开更多
Due to their resource constraints,Internet of Things(IoT)devices require authentication mechanisms that are both secure and efficient.Elliptic curve cryptography(ECC)meets these needs by providing strong security with...Due to their resource constraints,Internet of Things(IoT)devices require authentication mechanisms that are both secure and efficient.Elliptic curve cryptography(ECC)meets these needs by providing strong security with shorter key lengths,which significantly reduces the computational overhead required for authentication algorithms.This paper introduces a novel ECC-based IoT authentication system utilizing our previously proposed efficient mapping and reverse mapping operations on elliptic curves over prime fields.By reducing reliance on costly point multiplication,the proposed algorithm significantly improves execution time,storage requirements,and communication cost across varying security levels.The proposed authentication protocol demonstrates superior performance when benchmarked against relevant ECC-based schemes,achieving reductions of up to 35.83%in communication overhead,62.51%in device-side storage consumption,and 71.96%in computational cost.The security robustness of the scheme is substantiated through formal analysis using the Automated Validation of Internet Security Protocols and Applications(AVISPA)tool and Burrows-Abadir-Needham(BAN)logic,complemented by a comprehensive informal analysis that confirms its resilience against various attack models,including impersonation,replay,and man-in-the-middle attacks.Empirical evaluation under simulated conditions demonstrates notable gains in efficiency and security.While these results indicate the protocol’s strong potential for scalable IoT deployments,further validation on real-world embedded platforms is required to confirm its applicability and robustness at scale.展开更多
文摘Recently, a statement by the Beijing Administration for Industry and Commerce stopping restaurants and catering services from banning outside beverages has provoked heated debate among the public.
文摘In recent years,interest in banning smartphones in schools has increased.This has become a policy in several US states and municipalities,with other states considering them.The UK continues to debate such policies.Other countries ranging from France to China have also implemented bans on smartphones in schools.However,do such bans work(i.e.,improve grades,mental health,reduce bullying,etc.)?
文摘随着电力物联网技术的快速发展,建设能源互联网具有重大意义。电力物联终端设备的识别认证是保障能源互联网安全稳定运行的基础。为实现海量电力终端设备信息高效采集与安全认证,研究提出一种面向电力物联网的RFID(radio frequency identification)认证方案,该方案利用RFID技术,基于国密SM3和SM4设计算法,实现了阅读器与电力设备之间的相互认证,保障了电力通信数据的传输安全,降低设备标签的计算复杂度。安全性分析表明,该方案满足不可追踪性、抗重放攻击、抗去同步攻击、抗拒绝服务攻击等安全特性,BAN逻辑分析进一步表明该方案满足相互认证性。性能分析表明,该方案在标签计算量、存储量、通信量及数据库搜索效率方面具有较好的性能优势。
基金supported by the Science Achievement Scholarship of Thailand (SAST)the support of Office of Atom for Peace,Thailand and Thailand Institute of Nuclear Technology (a public organization) for providing facilities for some experiment in this work。
文摘The fossil shells on the sedimentary rocks were collected from The Historical Park,Ban Sap Noi Geopark,Phetchabun Province,Thailand.However,the fossils remained in this area were investigated on the characteristic species only in geological studies with taxonomy for fossil age predicting.To fill up the gap of these studies,the material characterization techniques were used to study the chemical composition and structure of fossil shells I,II and III.The results clearly showed that the morphologies of all fossil shells were Brachiopod fossils with different species.The functional group and elemental composition of all fossil shells showed that the high content of calcium carbonate was a major composition.In addition,the high content of quartz indicated the silica precipitation phenomenon in all fossil shells.The element composition of cross-sectional morphology and energy dispersive spectroscope (EDS mapping) were used to confirm the presence of Si element in each zone of fossil shells.The crystal structures of all fossil shells were investigated and indicated that the calcium carbonate compound was a calcite phase and silicon dioxide compound was a quartz phase.Moreover,the crystal structure of quartz phase was used to calculate the crystallinity index.The crystallinity index values in all fossil shells indicated a well-crystallized quartz.The age of fossil shells was estimated and found to be brachiopod fossil in carboniferous period with the age of about 359.2 to 299.0 million years.
文摘该文旨在探讨吐蕃时期连接象雄与胡密国之间的关键交通路线,并深入分析该路线在东西方文化交流与贸易往来中所发挥的重要作用。象雄作为吐蕃西部重镇,凭借其独特地理位置,成为中亚与吐蕃文化交流的重要中转站;胡密国(即敦煌吐蕃藏文文献Or.8212/187中所载“Ban vjag nag bo”),位于今阿富汗巴达赫尚省瓦罕走廊一带,也因其地理优势成为东西文明交汇的重要节点。因此,考察象雄至胡密国的交通路线,对理解吐蕃在中亚地区的战略布局与文化影响具有重要意义。该文综合文献记载与考古研究成果,从以下三方面展开论述:第一,通过分析交通要冲勃律地区的战事,推断吐蕃征服勃律的大致年代,揭示其首次尝试打通中亚通道的战略意图;第二,借助拉达克、巴尔蒂斯坦、吉尔吉特、瓦罕等地现存吐蕃时期藏文石刻的地理分布,勾勒出吐蕃经营该路线的具体路径与年代;第三,结合唐代方志、游记等汉文史料中有关拉达克与瓦罕之间的往来记载,进一步还原该路线的实际运作情况。通过深入探讨该路线的战略意义、运作机制与历史作用,有助于更清晰地认识吐蕃在中亚地区的活动及其对东西方文化交流的贡献。
文摘Due to their resource constraints,Internet of Things(IoT)devices require authentication mechanisms that are both secure and efficient.Elliptic curve cryptography(ECC)meets these needs by providing strong security with shorter key lengths,which significantly reduces the computational overhead required for authentication algorithms.This paper introduces a novel ECC-based IoT authentication system utilizing our previously proposed efficient mapping and reverse mapping operations on elliptic curves over prime fields.By reducing reliance on costly point multiplication,the proposed algorithm significantly improves execution time,storage requirements,and communication cost across varying security levels.The proposed authentication protocol demonstrates superior performance when benchmarked against relevant ECC-based schemes,achieving reductions of up to 35.83%in communication overhead,62.51%in device-side storage consumption,and 71.96%in computational cost.The security robustness of the scheme is substantiated through formal analysis using the Automated Validation of Internet Security Protocols and Applications(AVISPA)tool and Burrows-Abadir-Needham(BAN)logic,complemented by a comprehensive informal analysis that confirms its resilience against various attack models,including impersonation,replay,and man-in-the-middle attacks.Empirical evaluation under simulated conditions demonstrates notable gains in efficiency and security.While these results indicate the protocol’s strong potential for scalable IoT deployments,further validation on real-world embedded platforms is required to confirm its applicability and robustness at scale.
