With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A mag...With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A magnetic phase-coding meta-atom(MPM)is formed by the heterogeneous integration of La:YIG magneto-optical(MO)materials and Si microstructures.The MPM couples the magnetic induction phase of spin states with the propagation phase and can simultaneously satisfy the required output phase for dual frequencies under various external magnetic fields to realize the dynamic beam steering among multiple channels at 0.25 and 0.5 THz.The energy ratio of the target direction can reach 96.5%,and the nonreciprocal one-way transmission with a max isolation of 29.8 dB is realized due to the nonreciprocal phase shift of the MO layer.This nonreciprocal mechanism of magnetic induction reshaping of wavefront significantly holds promise for advancing integrated multi-functional THz devices with the characteristics of low-crosstalk,multi-channel,and multi-frequency,and has great potential to promote the development of THz large-capacity and high-speed communication.展开更多
Rotational feeding combined with shift feeding electrochemical trepanning(RF-SF ECTr)is an effective method for machining aeroengine blisks.However,given the variable relative motion of the electrodes and the complex ...Rotational feeding combined with shift feeding electrochemical trepanning(RF-SF ECTr)is an effective method for machining aeroengine blisks.However,given the variable relative motion of the electrodes and the complex flow channels around the bending and twisting blades,the accessibility and uniformity of the flow field are poor in blisk RF-SF ECTr using the traditional electrolyte supply(TES)mode,resulting in poor machining stability and low machining efficiency.To improve the distribution of the flow field,a new multi-channel electrolyte supply(MCES)mode is proposed for blisk RF-SF ECTr,in which the position and volume of the electrolyte supply are controlled effectively by setting multiple inlet channels in the liquid inlet area.A flow-field simulation comparison between TES and MCES shows that better accessibility and uniformity of the flow-field distribution are achieved under MCES.To clarify further the flow-field distribution characteristics under RF-SF ECTr,a series of flow-field simulations was conducted at different machining depths.Based on the obtained dynamic change law for the flow field,to enhance further its uniformity and accessibility,a global coverage strategy for the electrolyte supply and a flow-field structure optimization method for MCES are proposed,which involve optimizing the number,diameter,and location of the inlet channels.After many simulations,the optimal MCES structure was achieved whereby the electrolyte covers all positions effectively in the processing area.To verify the proposed method as effective and correct,a series of RF-SF ECTr experiments was carried out.Under the optimized MCES mode,the feeding rate was increased from 0.8 mm/min with the TES mode to 2.0 mm/min,and the processing stability and efficiency were improved significantly.The methods presented here offer an effective guide for flow-field optimization when machining other components with complex spatial structures.展开更多
Vortex beams carrying orbital angular momentum(OAM)are of great significance for high-capacity communication and super-resolution imaging.However,there is a huge gap between the free-space vortices(FVs)and plasmonic v...Vortex beams carrying orbital angular momentum(OAM)are of great significance for high-capacity communication and super-resolution imaging.However,there is a huge gap between the free-space vortices(FVs)and plasmonic vortices(PVs)on chips,and active manipulation as well as multiplexing in more channels have become a pressing demand.In this work,we demonstrate a terahertz(THz)cascaded metadevice composed of a helical plasmonic metasurface,a liquid crystal(LC)layer,and a helical dielectric metasurface.By spin-orbital angular momentum coupling and photon state superposition,PVs and FVs are generated with mode purity of over 85%on average.Due to the inversion asymmetric design of the helical metasurfaces,the parity symmetry breaking of OAM is realized(the topological charge numbers no longer occur in positive and negative pairs,but all are positive),generating 6 independent channels associated with the decoupled spin states and the near-/far-field positions.Moreover,by the LC integration,dynamic mode switching and energy distribution can be realized,finally obtaining up to 12 modes with a modulation ratio of above 70%.This active tuning and multi-channel multiplexing metadevice establishes a bridge connection between the PVs and FVs,exhibiting promising applications in THz communication,intelligent perception,and information processing.展开更多
BACKGROUND Radical gastrectomy(RGE)for gastric carcinoma(GC)has exerted definite therapeutic efficacy in treating patients with GC.However,a notable risk of postoperative complications(POCs)persists among middle-aged ...BACKGROUND Radical gastrectomy(RGE)for gastric carcinoma(GC)has exerted definite therapeutic efficacy in treating patients with GC.However,a notable risk of postoperative complications(POCs)persists among middle-aged and elderly patients with compromised physiological functions.Hence,developing and implementing reliable nursing interventions to optimize the comprehensive management of these patients is deemed imperative.AIM To analyze the association of multi-channel continuous nursing intervention with POCs,negative emotions(NEs),and quality of life(QoL)of patients undergoing RGE for GC.METHODS This retrospective study selected 99 patients who underwent RGE for GC in our hospital from May 2020 to May 2023.Participants were categorized into the control(n=49 cases)and research groups(n=50 cases)receiving routine and multi-channel continuous nursing care,respectively.Comparative analysis involved data on postoperative rehabilitation(time to first anal exhaust,oral feeding and ambulation,and hospital stay),complications(nausea and vomiting,delayed gastric emptying,and abdominal distension),NEs[Self-rating Anxiety(SAS)/Depression Scale(SDS)],treatment compliance,self-efficacy,and QoL[World Health Organization QoL Brief Version(WHOQOL-BREF)].RESULTS Compared to the control group,the research group demonstrated earlier first postoperative anal exhaust,oral feeding,and ambulation,shorter hospital stay,lower POC rate,and more reduced SAS and SDS scores postintervention,which was significantly lower than the baseline.The treatment compliance scores were significantly higher in the research group than in the control group in terms of medication adherence,daily exercise,reasonable diet,and regular review.Further,the research group demonstrated increased self-efficacy scores in terms of positive attitude,self-stress relief,and self-decision-making,as well as the overall score postintervention,which were higher than the control group.Moreover,the research group reported notably higher WHOQOL-BREF scores in domains such as physiology,psychology,social relations,and environment.CONCLUSION Multi-channel continuous nursing intervention prevents POCs in patients undergoing RGE for GC as well as significantly alleviates patients’NEs and boosts their QoL.展开更多
We study a novel replication mechanism to ensure service continuity against multiple simultaneous server failures.In this mechanism,each item represents a computing task and is replicated intoξ+1 servers for some int...We study a novel replication mechanism to ensure service continuity against multiple simultaneous server failures.In this mechanism,each item represents a computing task and is replicated intoξ+1 servers for some integerξ≥1,with workloads specified by the amount of required resources.If one or more servers fail,the affected workloads can be redirected to other servers that host replicas associated with the same item,such that the service is not interrupted by the failure of up toξservers.This requires that any feasible assignment algorithm must reserve some capacity in each server to accommodate the workload redirected from potential failed servers without overloading,and determining the optimal method for reserving capacity becomes a key issue.Unlike existing algorithms that assume that no two servers share replicas of more than one item,we first formulate capacity reservation for a general arbitrary scenario.Due to the combinatorial nature of this problem,finding the optimal solution is difficult.To this end,we propose a Generalized and Simple Calculating Reserved Capacity(GSCRC)algorithm,with a time complexity only related to the number of items packed in the server.In conjunction with GSCRC,we propose a robust replica packing algorithm with capacity optimization(RobustPack),which aims to minimize the number of servers hosting replicas and tolerate multiple server failures.Through theoretical analysis and experimental evaluations,we show that the RobustPack algorithm can achieve better performance.展开更多
The Internet of Things(IoT)and allied applications have made real-time responsiveness for massive devices over the Internet essential.Cloud-edge/fog ensembles handle such applications'computations.For Beyond 5 th ...The Internet of Things(IoT)and allied applications have made real-time responsiveness for massive devices over the Internet essential.Cloud-edge/fog ensembles handle such applications'computations.For Beyond 5 th Generation(B5G)communication paradigms,Edge Servers(ESs)must be placed within Information Communication Technology infrastructures to meet Quality of Service requirements like response time and resource utilisation.Due to the large number of Base Stations(BSs)and ESs and the possibility of significant variations in placing the ESs within the IoTs geographical expanse for optimising multiple objectives,the Edge Server Placement Problem(ESPP)is NP-hard.Thus,stochastic evolutionary metaheuristics are natural.This work addresses the ESPP using a Particle Swarm Optimization that initialises particles as BS positions within the geography to maintain the workload while scanning through all feasible sets of BSs as an encoded sequence.The Workload-Threshold Aware Sequence Encoding(WTASE)Scheme for ESPP provides the number of ESs to be deployed,similar to existing methodologies and exact locations for their placements without the overhead of maintaining a prohibitively large distance matrix.Simulation tests using open-source datasets show that the suggested technique improves ESs utilisation rate,workload balance,and average energy consumption by 36%,17%,and 32%,respectively,compared to prior works.展开更多
本文在AJAX理念的指导下,针对WebGIS的不足之处,设计与实现了城市交通矢量WebGIS原型系统。原型系统以ArcGIS Server WebADF框架为核心构建地图引擎,以AJAX开源引擎ExtJS作为前端辅助工具实现查询以及统计分析功能。试验表明,基于AJAX...本文在AJAX理念的指导下,针对WebGIS的不足之处,设计与实现了城市交通矢量WebGIS原型系统。原型系统以ArcGIS Server WebADF框架为核心构建地图引擎,以AJAX开源引擎ExtJS作为前端辅助工具实现查询以及统计分析功能。试验表明,基于AJAX的富客户端WebGIS架构减轻了服务器端的负载,提升了客户端的运行效率,更加高效地提供了Web地理信息服务。展开更多
ArcGIS Server是ESRI公司基于IT工业标准推出的企业级WebGIS应用平台,它支持GIS功能集中管理和多用户负载均衡。ArcGIS Server GIS服务器运行机制复杂,部署基于ArcGIS Server API开发的Web应用程序或Web服务程序,需要考虑Web服务器、GI...ArcGIS Server是ESRI公司基于IT工业标准推出的企业级WebGIS应用平台,它支持GIS功能集中管理和多用户负载均衡。ArcGIS Server GIS服务器运行机制复杂,部署基于ArcGIS Server API开发的Web应用程序或Web服务程序,需要考虑Web服务器、GIS服务器和数据库服务器的配置和部署。本文通过研究ArcGIS Server的分布式体系结构和GIS服务器的运行机制,同时根据可用的硬件和软件资源,采取合理的服务器配置策略,以达到合理利用资源和有效发挥系统性能的目的。展开更多
在设计海洋环境信息产品的内容、表现方式、发布流程的基础上,应用ArcGIS Server平台和ArcGIS API for Flex客户端开发技术,建立了海洋环境信息服务系统(MEISS),实现信息产品的发布、审核和可视化展示等功能。该系统可查询展示我国管辖...在设计海洋环境信息产品的内容、表现方式、发布流程的基础上,应用ArcGIS Server平台和ArcGIS API for Flex客户端开发技术,建立了海洋环境信息服务系统(MEISS),实现信息产品的发布、审核和可视化展示等功能。该系统可查询展示我国管辖海域的自然地理、水文动力、环境质量、敏感目标、区域保护与开发利用现状、海洋环境监测评价等信息,为海洋环境保护、海洋科学研究和海洋权益维护提供信息服务和决策支持。展开更多
基金supported by the National Natural Science Foun-dation of China(Grant Nos.62371258,62335012,62205160,and 62435010)the Tianjin Youth Science and Technology Talent Project(Grant No.QN20230227)+1 种基金the Natural Science Foundation of Tianjin(Grant No.24JCYBJC01860)the Fundamental Research Funds for the Central Universities,Nan-kai University(Grant No.075-63253215).
文摘With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A magnetic phase-coding meta-atom(MPM)is formed by the heterogeneous integration of La:YIG magneto-optical(MO)materials and Si microstructures.The MPM couples the magnetic induction phase of spin states with the propagation phase and can simultaneously satisfy the required output phase for dual frequencies under various external magnetic fields to realize the dynamic beam steering among multiple channels at 0.25 and 0.5 THz.The energy ratio of the target direction can reach 96.5%,and the nonreciprocal one-way transmission with a max isolation of 29.8 dB is realized due to the nonreciprocal phase shift of the MO layer.This nonreciprocal mechanism of magnetic induction reshaping of wavefront significantly holds promise for advancing integrated multi-functional THz devices with the characteristics of low-crosstalk,multi-channel,and multi-frequency,and has great potential to promote the development of THz large-capacity and high-speed communication.
基金Supported by National Natural Science Foundation of China(Grant Nos.52275435,52075465,52375519)Open Fund Project of Jiangsu Key Laboratory of Precision and Micro-manufacturing Technology(Grant No.JSKL2324K03)Key Research and Development Program of Hunan Province of China(Grant No.2023GK2026)。
文摘Rotational feeding combined with shift feeding electrochemical trepanning(RF-SF ECTr)is an effective method for machining aeroengine blisks.However,given the variable relative motion of the electrodes and the complex flow channels around the bending and twisting blades,the accessibility and uniformity of the flow field are poor in blisk RF-SF ECTr using the traditional electrolyte supply(TES)mode,resulting in poor machining stability and low machining efficiency.To improve the distribution of the flow field,a new multi-channel electrolyte supply(MCES)mode is proposed for blisk RF-SF ECTr,in which the position and volume of the electrolyte supply are controlled effectively by setting multiple inlet channels in the liquid inlet area.A flow-field simulation comparison between TES and MCES shows that better accessibility and uniformity of the flow-field distribution are achieved under MCES.To clarify further the flow-field distribution characteristics under RF-SF ECTr,a series of flow-field simulations was conducted at different machining depths.Based on the obtained dynamic change law for the flow field,to enhance further its uniformity and accessibility,a global coverage strategy for the electrolyte supply and a flow-field structure optimization method for MCES are proposed,which involve optimizing the number,diameter,and location of the inlet channels.After many simulations,the optimal MCES structure was achieved whereby the electrolyte covers all positions effectively in the processing area.To verify the proposed method as effective and correct,a series of RF-SF ECTr experiments was carried out.Under the optimized MCES mode,the feeding rate was increased from 0.8 mm/min with the TES mode to 2.0 mm/min,and the processing stability and efficiency were improved significantly.The methods presented here offer an effective guide for flow-field optimization when machining other components with complex spatial structures.
基金supported by the National Natural Science Foundation of China(62335012,62371258,624B2075,62205160,62435010)Young Scientific and Technological Talents in Tianjin(QN20230227)Fundamental Research Funds for the Central Universities,Nankai University(63231159).
文摘Vortex beams carrying orbital angular momentum(OAM)are of great significance for high-capacity communication and super-resolution imaging.However,there is a huge gap between the free-space vortices(FVs)and plasmonic vortices(PVs)on chips,and active manipulation as well as multiplexing in more channels have become a pressing demand.In this work,we demonstrate a terahertz(THz)cascaded metadevice composed of a helical plasmonic metasurface,a liquid crystal(LC)layer,and a helical dielectric metasurface.By spin-orbital angular momentum coupling and photon state superposition,PVs and FVs are generated with mode purity of over 85%on average.Due to the inversion asymmetric design of the helical metasurfaces,the parity symmetry breaking of OAM is realized(the topological charge numbers no longer occur in positive and negative pairs,but all are positive),generating 6 independent channels associated with the decoupled spin states and the near-/far-field positions.Moreover,by the LC integration,dynamic mode switching and energy distribution can be realized,finally obtaining up to 12 modes with a modulation ratio of above 70%.This active tuning and multi-channel multiplexing metadevice establishes a bridge connection between the PVs and FVs,exhibiting promising applications in THz communication,intelligent perception,and information processing.
文摘BACKGROUND Radical gastrectomy(RGE)for gastric carcinoma(GC)has exerted definite therapeutic efficacy in treating patients with GC.However,a notable risk of postoperative complications(POCs)persists among middle-aged and elderly patients with compromised physiological functions.Hence,developing and implementing reliable nursing interventions to optimize the comprehensive management of these patients is deemed imperative.AIM To analyze the association of multi-channel continuous nursing intervention with POCs,negative emotions(NEs),and quality of life(QoL)of patients undergoing RGE for GC.METHODS This retrospective study selected 99 patients who underwent RGE for GC in our hospital from May 2020 to May 2023.Participants were categorized into the control(n=49 cases)and research groups(n=50 cases)receiving routine and multi-channel continuous nursing care,respectively.Comparative analysis involved data on postoperative rehabilitation(time to first anal exhaust,oral feeding and ambulation,and hospital stay),complications(nausea and vomiting,delayed gastric emptying,and abdominal distension),NEs[Self-rating Anxiety(SAS)/Depression Scale(SDS)],treatment compliance,self-efficacy,and QoL[World Health Organization QoL Brief Version(WHOQOL-BREF)].RESULTS Compared to the control group,the research group demonstrated earlier first postoperative anal exhaust,oral feeding,and ambulation,shorter hospital stay,lower POC rate,and more reduced SAS and SDS scores postintervention,which was significantly lower than the baseline.The treatment compliance scores were significantly higher in the research group than in the control group in terms of medication adherence,daily exercise,reasonable diet,and regular review.Further,the research group demonstrated increased self-efficacy scores in terms of positive attitude,self-stress relief,and self-decision-making,as well as the overall score postintervention,which were higher than the control group.Moreover,the research group reported notably higher WHOQOL-BREF scores in domains such as physiology,psychology,social relations,and environment.CONCLUSION Multi-channel continuous nursing intervention prevents POCs in patients undergoing RGE for GC as well as significantly alleviates patients’NEs and boosts their QoL.
基金supported in part by the National Key R&D Program of China under No.2023YFB2703800the National Science Foundation of China under Grants U22B2027,62172297,62102262,61902276 and 62272311+3 种基金Tianjin Intelligent Manufacturing Special Fund Project under Grants 20211097the China Guangxi Science and Technology Plan Project(Guangxi Science and Technology Base and Talent Special Project)under Grant AD23026096(Application Number 2022AC20001)Henan Provincial Natural Science Foundation of China under Grant 622RC616CCF-Nsfocus Kunpeng Fund Project under Grants CCF-NSFOCUS202207。
文摘We study a novel replication mechanism to ensure service continuity against multiple simultaneous server failures.In this mechanism,each item represents a computing task and is replicated intoξ+1 servers for some integerξ≥1,with workloads specified by the amount of required resources.If one or more servers fail,the affected workloads can be redirected to other servers that host replicas associated with the same item,such that the service is not interrupted by the failure of up toξservers.This requires that any feasible assignment algorithm must reserve some capacity in each server to accommodate the workload redirected from potential failed servers without overloading,and determining the optimal method for reserving capacity becomes a key issue.Unlike existing algorithms that assume that no two servers share replicas of more than one item,we first formulate capacity reservation for a general arbitrary scenario.Due to the combinatorial nature of this problem,finding the optimal solution is difficult.To this end,we propose a Generalized and Simple Calculating Reserved Capacity(GSCRC)algorithm,with a time complexity only related to the number of items packed in the server.In conjunction with GSCRC,we propose a robust replica packing algorithm with capacity optimization(RobustPack),which aims to minimize the number of servers hosting replicas and tolerate multiple server failures.Through theoretical analysis and experimental evaluations,we show that the RobustPack algorithm can achieve better performance.
基金the Deanship of Research and Graduate Studies at King Khalid University for funding this work through the Large Research Project under grant number RGP2/603/46。
文摘The Internet of Things(IoT)and allied applications have made real-time responsiveness for massive devices over the Internet essential.Cloud-edge/fog ensembles handle such applications'computations.For Beyond 5 th Generation(B5G)communication paradigms,Edge Servers(ESs)must be placed within Information Communication Technology infrastructures to meet Quality of Service requirements like response time and resource utilisation.Due to the large number of Base Stations(BSs)and ESs and the possibility of significant variations in placing the ESs within the IoTs geographical expanse for optimising multiple objectives,the Edge Server Placement Problem(ESPP)is NP-hard.Thus,stochastic evolutionary metaheuristics are natural.This work addresses the ESPP using a Particle Swarm Optimization that initialises particles as BS positions within the geography to maintain the workload while scanning through all feasible sets of BSs as an encoded sequence.The Workload-Threshold Aware Sequence Encoding(WTASE)Scheme for ESPP provides the number of ESs to be deployed,similar to existing methodologies and exact locations for their placements without the overhead of maintaining a prohibitively large distance matrix.Simulation tests using open-source datasets show that the suggested technique improves ESs utilisation rate,workload balance,and average energy consumption by 36%,17%,and 32%,respectively,compared to prior works.
文摘本文在AJAX理念的指导下,针对WebGIS的不足之处,设计与实现了城市交通矢量WebGIS原型系统。原型系统以ArcGIS Server WebADF框架为核心构建地图引擎,以AJAX开源引擎ExtJS作为前端辅助工具实现查询以及统计分析功能。试验表明,基于AJAX的富客户端WebGIS架构减轻了服务器端的负载,提升了客户端的运行效率,更加高效地提供了Web地理信息服务。
文摘ArcGIS Server是ESRI公司基于IT工业标准推出的企业级WebGIS应用平台,它支持GIS功能集中管理和多用户负载均衡。ArcGIS Server GIS服务器运行机制复杂,部署基于ArcGIS Server API开发的Web应用程序或Web服务程序,需要考虑Web服务器、GIS服务器和数据库服务器的配置和部署。本文通过研究ArcGIS Server的分布式体系结构和GIS服务器的运行机制,同时根据可用的硬件和软件资源,采取合理的服务器配置策略,以达到合理利用资源和有效发挥系统性能的目的。
文摘在设计海洋环境信息产品的内容、表现方式、发布流程的基础上,应用ArcGIS Server平台和ArcGIS API for Flex客户端开发技术,建立了海洋环境信息服务系统(MEISS),实现信息产品的发布、审核和可视化展示等功能。该系统可查询展示我国管辖海域的自然地理、水文动力、环境质量、敏感目标、区域保护与开发利用现状、海洋环境监测评价等信息,为海洋环境保护、海洋科学研究和海洋权益维护提供信息服务和决策支持。
