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P4LoF: Scheduling Loop-Free Multi-Flow Updates in Programmable Networks
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作者 Jiqiang Xia Qi Zhan +2 位作者 Le Tian Yuxiang Hu Jianhua Peng 《Computers, Materials & Continua》 2026年第1期1236-1254,共19页
The rapid growth of distributed data-centric applications and AI workloads increases demand for low-latency,high-throughput communication,necessitating frequent and flexible updates to network routing configurations.H... The rapid growth of distributed data-centric applications and AI workloads increases demand for low-latency,high-throughput communication,necessitating frequent and flexible updates to network routing configurations.However,maintaining consistent forwarding states during these updates is challenging,particularly when rerouting multiple flows simultaneously.Existing approaches pay little attention to multi-flow update,where improper update sequences across data plane nodes may construct deadlock dependencies.Moreover,these methods typically involve excessive control-data plane interactions,incurring significant resource overhead and performance degradation.This paper presents P4LoF,an efficient loop-free update approach that enables the controller to reroute multiple flows through minimal interactions.P4LoF first utilizes a greedy-based algorithm to generate the shortest update dependency chain for the single-flow update.These chains are then dynamically merged into a dependency graph and resolved as a Shortest Common Super-sequence(SCS)problem to produce the update sequence of multi-flow update.To address deadlock dependencies in multi-flow updates,P4LoF builds a deadlock-fix forwarding model that leverages the flexible packet processing capabilities of the programmable data plane.Experimental results show that P4LoF reduces control-data plane interactions by at least 32.6%with modest overhead,while effectively guaranteeing loop-free consistency. 展开更多
关键词 Network management update consistency programmable data plane P4
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TV Programmes
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作者 卢爱龙 《疯狂英语(初中天地)》 2002年第38期22-22,共1页
TV Programmes, Monday,June 12,2002 (CCTV) Channel 1 18:00 TV Classroom: Computer 18 : 30 Popular Music 19 : 00 News 19 : 30 Weather Report 19:40 Today's Focus(焦点)
关键词 TV programmes World
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Antibiotic stewardship programmes in intensive care units:Why,how,and where are they leading us 被引量:1
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作者 Yu-Zhi Zhang Suveer Singh 《World Journal of Critical Care Medicine》 2015年第1期13-28,共16页
Antibiotic usage and increasing antimicrobial resistance(AMR) mount significant challenges to patient safety and management of the critically ill on intensive care units(ICU). Antibiotic stewardship programmes(ASPs) a... Antibiotic usage and increasing antimicrobial resistance(AMR) mount significant challenges to patient safety and management of the critically ill on intensive care units(ICU). Antibiotic stewardship programmes(ASPs) aim to optimise appropriate antibiotic treatment whilst minimising antibiotic resistance. Different models of ASP in intensive care setting, include "standard" control of antibiotic prescribing such as "de-escalation strategies"through to interventional approaches utilising biomarkerguided antibiotic prescribing. A systematic review of outcomes related studies for ASPs in an ICU setting was conducted. Forty three studies were identified from MEDLINE between 1996 and 2014. Of 34 nonprotocolised studies, [1 randomised control trial(RCT), 22 observational and 11 case series], 29(85%) were positive with respect to one or more outcome: These were the key outcome of reduced antibiotic use, or ICU length of stay, antibiotic resistance, or prescribing cost burden. Limitations of non-standard antibiotic initiation triggers, patient and antibiotic selection bias or baseline demographic variance were identified. All 9 protocolised studies were RCTs, of which 8 were procalcitonin(PCT) guided antibiotic stop/start interventions. Five studies addressed antibiotic escalation, 3 de-escalation and 1 addressed both. Six studies reported positive outcomes for reduced antibiotic use, ICU length of stay or antibiotic resistance. PCT based ASPs are effective as antibiotic-stop(de-escalation) triggers, but not as an escalation trigger alone. PCT has also been effective in reducing antibiotic usage without worsening morbidity or mortality in ventilator associated pulmonary infection. No study has demonstrated survival benefit of ASP. Ongoing challenges to infectious disease management, reported by the World Health Organisation global report 2014, are high AMR to newer antibiotics, and regional knowledge gaps in AMR surveillance. Improved AMR surveillance data, identifying core aspects of successful ASPs that are transferable, and further well-conducted trials will be necessary if ASPs are to be an effective platform for delivering desired patient outcomes and safety through best antibiotic policy. 展开更多
关键词 Antibiotic STEWARDSHIP programmE INTENSIVE care Antimicrobial RESISTANCE Antibacterial RESISTANCE Antibiotic RESISTANCE
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Training Teachers for Extensive Reading Programmes
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作者 马超 《海外英语》 2014年第17期292-293,296,共3页
It has been suggested that the success of an ER project can largely rely on several elements,such as the selection of appropriate materials,establishment of management system,workshop for training teachers. Among thos... It has been suggested that the success of an ER project can largely rely on several elements,such as the selection of appropriate materials,establishment of management system,workshop for training teachers. Among those,teachers play an indispensable role due to the fact that it is the teachers who are capable of turning conceptions into actions,who get students engaged and bridge and gap between the goals of the programme and the reality in classroom. This paper is an attempt to outline a detailed picture to demonstrate how to offer effective training courses which can enable teachers to play"multiple roles"to make great contribution to the development of an ER project. 展开更多
关键词 TRAINING TEACHERS ER programmE multiple ROLES
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Evaluation of BSc Radiologic Sciences and Medical Imaging Technology Programmes in Sudanese Universities from Students’ Perspective
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作者 Awad Mohamed Elkhadir 《Open Journal of Radiology》 2015年第4期205-211,共7页
This study sets the objective to involve undergraduate students in the evaluation of radiologic sciences and medical imaging technology programmes in Sudanese universities. Based on the analysis of survey results in w... This study sets the objective to involve undergraduate students in the evaluation of radiologic sciences and medical imaging technology programmes in Sudanese universities. Based on the analysis of survey results in which the participants (BSc students undertaking radiologic sciences and medical imaging technology programmes at university level) are asked to answer both closed and open-ended questions, the study seeks to reveal the participants’ perceptions and introspections about the radiologic sciences and medical imaging technology programmes in Sudan. It also attempts to explore the participants’ suggestions and recommendations as to enhance the quality of these programmes with an eye to helping syllabus designers to improve these programmes, thereby bettering healthcare services for the larger good to the community. A brief cross-sectional survey is completed by a total of 105 radiologic sciences and medical imaging technology students, i.e. 39 (37.1%) third-year students and 66 (62.9%) fourth-year students. The majority of participants is satisfied with the programmes, indicating that they are up-to-date and ran abreast with the latest developments in the field. Very few suggest that the programmes should be reviewed for revision, implying that there is room for improvement. Some participants recommend that more training hours in modern imaging modalities (e.g. MRI, CT and U/S) should be introduced. Only one participant recommends the introduction of advanced training centres. 展开更多
关键词 programmes EVALUATION RADIOLOGIC Medical Imaging Technology SUDAN
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Forests Policies and Programmes in India: Implications for Climate Change Adaptation
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作者 Indu K. Murthy Poornima Kumar 《Open Journal of Forestry》 2019年第3期226-240,共15页
Climate change is a major global environmental and developmental challenge and climate proofing of vulnerable sectors, programmes, natural systems and communities by integrating adaptation and mitigation options into ... Climate change is a major global environmental and developmental challenge and climate proofing of vulnerable sectors, programmes, natural systems and communities by integrating adaptation and mitigation options into planning process are increasingly becoming an integral part of development. The basic premises on which this could happen are the national and sectoral policies that govern any programmes and actions implemented on ground. This study reviews existing policies, plans and programmes and their implications for climate change. Based on the analyses, key areas of research, policy initiatives and institutional and capacity development needs have been identified, to facilitate climate change adaptation. The forest policies formulated so far in India have been broadly aimed at conservation, reduction of pressure on forests and provisioning of biomass to the large forest dependent population for their fuel and fodder needs apart from generating revenue through production and sale of timber. However, these have not been formulated with climate change as a consideration and therefore may become less effective as climate change and its impacts become increasingly evident. The study clearly identifies that the current policies and programmes have elements/features and activities that directly or indirectly contribute positively towards adaptation, although the primary implications are towards biodiversity and to some extent ecosystem functioning. It finally highlights the need for incorporating climate change concerns in forest sector development programmes and also to address the issue of climate change. 展开更多
关键词 FOREST SECTOR CLIMATE Change Adaptation FOREST POLICIES programmes CLIMATE Variability
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Analysis on the Financial Impact Due to Non-compliance to Rules of the European Union Funding Programmes for Research
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作者 Alexandru Bocean 《Economics World》 2018年第5期415-423,共9页
The analysis is targeted on the financial impact of non-compliance to rules for European Union (EU) funding in thefield of research in quantitative terms, by examining statistical documents prepared by the European ... The analysis is targeted on the financial impact of non-compliance to rules for European Union (EU) funding in thefield of research in quantitative terms, by examining statistical documents prepared by the European Commissionwhich are available for the public and relate to the period 2008-2016. It is to be noted that these statisticaldocuments use the terminology of irregularity instead of error and it is seen as any breach of rules that may lead toa financial impact and to damage on the budget of the European Union. Details related to error and irregularityterms are included in this paper. In the research on the impact of irregularities for EU research funding, severaltasks were accomplished, such as highlighting the evolution of irregularities during the period under study, acomparison between reported irregularities in the research field and other EU policy areas for one year where thefinancial impact is the highest and an analysis of the types of irregularities identified by the statistical evaluationdocuments on irregularities. 展开更多
关键词 AUDIT ineligible framework programme RESEARCH IRREGULARITIES
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Exhibition Programmes in Beijing CCPIT 2002
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《China's Foreign Trade》 2002年第1期27-28,共2页
The 28th China Fur & Leather Products FairDATE: 16-19Jan2002 FREQUENCY: Annual FOUNDED YEAR: 1975 APPLICATION DEADLINE:
关键词 EMAIL Co TCI Exhibition programmes in Beijing CCPIT 2002
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Assessing Sport and Recreation Programmes' Service Quality at Hotels and Resorts" Towards Enhancing Customer Participation
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作者 Lim Khong Chiu Radzliyana Binti Radzuwan Cheah Swee Ting 《Journal of Tourism and Hospitality Management》 2014年第1期6-17,共12页
Many issues and challenges are faced by the managers programmes today. Although many previous researches on and professionals in managing sport and recreation service quality provided by the organizations had been exp... Many issues and challenges are faced by the managers programmes today. Although many previous researches on and professionals in managing sport and recreation service quality provided by the organizations had been explored, very few studies pertaining to service quality in sport and recreation programmes in local hotels and resorts have been emphasized. This study aims to assess customers' perceptions of service quality in sport and recreation programmes and to determine the differences between customers' perceptions of service quality in terms of their gender and nationality. A total of 450 respondents from the hotels and resorts located in coastal areas of the northern Peninsular Malaysia participated in the survey. They were asked to respond to a series of the adapted service quality (SERVQUAL) items to measure five dimensions of service quality including tangibles, assurance, responsiveness, reliability, and empathy. Results from this study revealed that the customers' perceptions of the overall services in sport and recreation programmes provided by the hotels and resorts were satisfactory. It was also indicated that there was no significant difference between male and female customers' perceptions of service quality in sport and recreation programmes. Conversely, the results revealed that there was a significant difference between local and foreign customers' perceptions of sport and recreation services provided. These findings had implications on sport and recreation programmes in relation to designing effective management and marketing strategies at hotels and resorts. 展开更多
关键词 customers' perceptions service quality sport and recreation programmes tourism industry
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National Social Investment Programmes in Nigeria:A Descriptive Analysis of the Socio-Economic Contributions of N-Power Programme in Benue State
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作者 Robert Idoko Ogwola Dennis Anyebe Olofu Charles Amobi Aneke 《Management Studies》 2024年第1期9-20,共12页
This study analysed the socio-economic contributions of N-Power programme amongst the beneficiaries of the scheme in Benue State.Prior to the introduction of N-Power programme,successive administrations in Nigeria hav... This study analysed the socio-economic contributions of N-Power programme amongst the beneficiaries of the scheme in Benue State.Prior to the introduction of N-Power programme,successive administrations in Nigeria have made concerted efforts towards improving the standard of living of the citizenry through the execution of various welfare or social intervention programmes,but not much successes were recorded.Learning from the mistakes of the past regimes,and by way of deliberate state policy,the Buhari’s government initiated a multi-pronged social investment policy,one of which is the N-power programme that came onboard in 2016,which also doubles as the subject of this study.To achieve the goal of this study,a combination of desktop research and survey design was employed.Questionnaires were administered to 390 respondents through a combination of stratified and random sampling techniques.The results of the survey were matched with that of the secondary data obtained through online websites and other related sources.The result indicated that N-Power made positive contributions to the socio-economic life of the beneficiaries in Benue State:specifically,the scheme contributed in poverty eradication,employment generation,skills acquisitions and capacity building.However,some aspect of our findings revealed that the programme has a number of challenges such as:inadequate cash support,delay in monthly cash transfer to beneficiaries,distance participants had to move to their work stations,absence of posting in N-Teach scheme,and lack of adequate working tools amongst others.To salvage this problem the paper recommended the following solutions:expansion of the scheme to cover N-Teach and other aspects,increment in the monthly cash transfer to cushion the high rate of inflation,support for the participants/beneficiaries in transportation and logistics,enrolment of more youth into the various schemes,proper monitoring and evaluation of the implementation of the schemes amongst others. 展开更多
关键词 NATIONAL social investment programme N-Power CONTRIBUTIONS socio-economic development
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Stakeholders’ Participation in Agricultural Farmers’ Extension Services Programmes in Sub-Saharan Africa: A Case of the Operation Wealth Creation (OWC) Programme in Uganda
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作者 Michael Peters Galukande-Kiganda Rose Nalumansi 《Economics World》 2021年第1期23-28,共6页
The paper presents findings from a study carried out to assess the contribution of stakeholders’participation on the performance of the national agricultural farmers’extension services programme in Uganda known as O... The paper presents findings from a study carried out to assess the contribution of stakeholders’participation on the performance of the national agricultural farmers’extension services programme in Uganda known as Operation Wealth Creation(OWEC).Specifically,the study sought to establish how participatory planning,budgeting,monitoring and evaluation(M&E)respectively contributed to the performance of OWC in selected district in central Uganda.The study adopted a cross-sectional survey design using both quantitative and qualitative data collection and analysis techniques and employed both questionnaires and interview guides on key participants in the programme.Findings of the study indicated positive relationships between stakeholders’participation and programme performance with participatory planning,budgeting and M&E all having positive significant effects on the performance of OWC programme.The study concluded that indeed stakeholders’participation contributed to improved performance of the OWC programme.The study recommends increased funding and M&E of the agricultural extension programmes for improved performance. 展开更多
关键词 stakeholders participation agricultural farmers’extension services Operation Wealth Creation programme
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A Regional Comparative Study of Distance Learning MBA Programmes in Selected Asian Countries
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作者 张建儒 赵平 《电子科技大学学报(社科版)》 2002年第3期21-25,共5页
Distance learning MBA programmes have increased tremendously in the past decade in selected Asian countries. This paper uses a stakeholders approach to conduct research on distance learning MBA programmes in Asian. Co... Distance learning MBA programmes have increased tremendously in the past decade in selected Asian countries. This paper uses a stakeholders approach to conduct research on distance learning MBA programmes in Asian. Conclusions of the research are then given. 展开更多
关键词 亚洲国家 远程MBA教学项目 区域性比较研究
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Fast-track rehabilitation plus humanized nursing improves gastrointestinal function and quality of life in post-surgical gastric cancer patients
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作者 Hua Li Hai-Jie Gao +2 位作者 Mei-Dai Wan Wan-Zhen Wang Xia Wu 《World Journal of Gastrointestinal Surgery》 2025年第10期135-142,共8页
BACKGROUND Postoperative complications(POCs)can arise in patients who underwent surgery for gastric cancer(GC).Effective nursing may help in minimizing these negative outcomes.AIM To elucidate the influence of fast-tr... BACKGROUND Postoperative complications(POCs)can arise in patients who underwent surgery for gastric cancer(GC).Effective nursing may help in minimizing these negative outcomes.AIM To elucidate the influence of fast-track rehabilitation(FTR)plus humanized nursing on gastrointestinal(GI)function and quality of life(QOL)of patients who underwent GC surgery.METHODS The study participants were 102 patients admitted between December 2018 and December 2020 for GC surgery,of which 52 and 50 patients who received FTR+humanized nursing(research group)and routine nursing(control group),respectively.GI function,QOL,POCs(abdominal distension,infection,GI bleeding,anastomotic leakage,and deep vein thrombosis)and nursing satisfaction were compared between the two groups.RESULTS Compared with the control group,the research group had better GI function,which was mainly manifested by earlier food intake,shorter bowel sound recovery time,short time to first postoperative anal exhaustion and defecation,and shorter length of stay.Besides,the research group exhibited better QOL,lower overall POC rate,and higher nursing satisfaction than the control group.CONCLUSION FTR+humanized nursing not only improve the GI function and QOL of patients undergoing GC surgery but also reduce the incidence of POCs and improve nursing satisfaction.Thus,this intervention deserves popularization in clinical practice. 展开更多
关键词 fast-track rehabilitation Humanized nursing Gastric cancer Gastrointestinal function Quality of life
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Programmable Hierarchical Kirigami Through Controlling Local Cuts
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作者 Han Pan Peng Sun +1 位作者 Lu Dai Rui Xiao 《Acta Mechanica Solida Sinica》 2025年第5期825-833,共9页
Kirigami,through introducing cuts into a thin sheet,can greatly improve the stretchability of structures and also generate complex patterns,showing potentials in various applications.Interestingly,even with the same c... Kirigami,through introducing cuts into a thin sheet,can greatly improve the stretchability of structures and also generate complex patterns,showing potentials in various applications.Interestingly,even with the same cutting pattern,the mechanical response of kirigami metamaterials can exhibit significant differences depending on the cutting angles in respect to the loading direction.In this work,we investigate the structural deformation of kirigami metamaterials with square domains and varied cutting angles of 0°and 45°.We further introduce a second level of cutting on the basis of the first cutting pattern.By combining experiments and finite element simulations,it is found that,compared to the commonly used 0°cuts,the two-level kirigami metamaterials with 45°cuts exhibit a unique alternating arrangement phenomenon of expanded/unexpanded states in the loading process,which also results in distinct stress–strain response.Through tuning the cutting patterns of metamaterials with 45°cuts,precise control of the rotation of the kirigami unit is realized,leading to kirigami metamaterials with encryption properties.The current work demonstrates the programmability of structural deformation in hierarchical kirigami metamaterials through controlling the local cutting modes. 展开更多
关键词 Kirigami metamaterials Hierarchical cuts programmable structure Buckling instability
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SP-Sketch:Persistent Flow Detection with Sliding Windows on Programmable Switches
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作者 Yuqian Huang Luyi Chen +1 位作者 Zilun Peng Lin Cui 《Computers, Materials & Continua》 2025年第9期6015-6034,共20页
Persistent flows are defined as network flows that persist over multiple time intervals and continue to exhibit activity over extended periods,which are critical for identifying long-term behaviors and subtle security... Persistent flows are defined as network flows that persist over multiple time intervals and continue to exhibit activity over extended periods,which are critical for identifying long-term behaviors and subtle security threats.Programmable switches provide line-rate packet processing to meet the requirements of high-speed network environments,yet they are fundamentally limited in computational and memory resources.Accurate and memoryefficient persistent flow detection on programmable switches is therefore essential.However,existing approaches often rely on fixed-window sketches or multiple sketches instances,which either suffer from insufficient temporal precision or incur substantial memory overhead,making them ineffective on programmable switches.To address these challenges,we propose SP-Sketch,an innovative sliding-window-based sketch that leverages a probabilistic update mechanism to emulate slot expiration without maintaining multiple sketch instances.This innovative design significantly reduces memory consumption while preserving high detection accuracy across multiple time intervals.We provide rigorous theoretical analyses of the estimation errors,deriving precise error bounds for the proposed method,and validate our approach through comprehensive implementations on both P4 hardware switches(with Intel Tofino ASIC)and software switches(i.e.,BMv2).Experimental evaluations using real-world traffic traces demonstrate that SP-Sketch outperforms traditional methods,improving accuracy by up to 20%over baseline sliding window approaches and enhancing recall by 5%compared to non-sliding alternatives.Furthermore,SP-Sketch achieves a significant reduction in memory utilization,reducing memory consumption by up to 65%compared to traditional methods,while maintaining a robust capability to accurately track persistent flow behavior over extended time periods. 展开更多
关键词 SKETCH persistent flow sliding window programmable switches probability subtraction
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Inverse Design of a NURBS-Based Chiral Metamaterial Via Machine Learning for Programmable Mechanical Deformation
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作者 Xiuhui Hou Wenhao Zhao +1 位作者 Kai Zhang Zichen Deng 《Acta Mechanica Solida Sinica》 2025年第5期739-748,共10页
Chiral metamaterials are manmade structures with extraordinary mechanical properties derived from their special geometric design instead of chemical composition.To make the mechanical deformation programmable,the non-... Chiral metamaterials are manmade structures with extraordinary mechanical properties derived from their special geometric design instead of chemical composition.To make the mechanical deformation programmable,the non-uniform rational B-spline(NURBS)curves are taken to replace the traditional ligament boundaries of the chiral structure.The Neural networks are innovatively inserted into the calculation of mechanical properties of the chiral structure instead of finite element methods to improve computational efficiency.For the problem of finding structure configuration with specified mechanical properties,such as Young’s modulus,Poisson’s ratio or deformation,an inverse design method using the Neural network-based proxy model is proposed to build the relationship between mechanical properties and geometric configuration.To satisfy some more complex deformation requirements,a non-homogeneous inverse design method is proposed and verified through simulation and experiments.Numerical and test results reveal the high computational efficiency and accuracy of the proposed method in the design of chiral metamaterials. 展开更多
关键词 Chiral metamaterials Inverse design Machine learning programmable mechanical deformation
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Body Temperature Programmable Shape Memory Thermoplastic Rubber
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作者 Taoxi Wang Zhuo Liu +5 位作者 Fu Jian Xing Shen Chen Wang Huwei Bian Tao Jiang Wei Min Huang 《Journal of Polymer Materials》 2025年第1期81-94,共14页
This paper presents the development of a thermoplastic shape memory rubber that can be programmed at human body temperature for comfortable fitting applications.We hybridized commercially available thermoplastic rubbe... This paper presents the development of a thermoplastic shape memory rubber that can be programmed at human body temperature for comfortable fitting applications.We hybridized commercially available thermoplastic rubber(TPR)used in the footwear industry with un-crosslinked polycaprolactone(PCL)to create two samples,namely TP6040 and TP7030.The shape memory behavior,elasticity,and thermo-mechanical response of these rubbers were systematically investigated.The experimental results demonstrated outstanding shape memory performance,with both samples achieving shape fixity ratios(Rf)and shape recovery ratios(R_(r))exceeding 94%.TP6040 exhibited a fitting time of 80 s at body temperature(37℃),indicating a rapid response for shape fixing.The materials also showed good elasticity before and after programming,which is crucial for comfort fitting.These findings suggest that the developed shape memory thermoplastic rubber has potential applications in personalized comfort fitting products,offering advantages over traditional customization techniques in terms of efficiency and cost-effectiveness. 展开更多
关键词 Thermoplastic rubber POLYCAPROLACTONE shape memory polymers body temperature programmable comfort fitting
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Machine learning-encoded multiscale modelling and Bayesian optimization framework to design programmable metamaterials
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作者 Yizhe Liu Xiaoyan Li +1 位作者 Yuli Chen Bin Ding 《Acta Mechanica Sinica》 2025年第1期226-245,共20页
Advanced programmable metamaterials with heterogeneous microstructures have become increasingly prevalent in scientific and engineering disciplines attributed to their tunable properties.However,exploring the structur... Advanced programmable metamaterials with heterogeneous microstructures have become increasingly prevalent in scientific and engineering disciplines attributed to their tunable properties.However,exploring the structure-property relationship in these materials,including forward prediction and inverse design,presents substantial challenges.The inhomogeneous microstructures significantly complicate traditional analytical or simulation-based approaches.Here,we establish a novel framework that integrates the machine learning(ML)-encoded multiscale computational method for forward prediction and Bayesian optimization for inverse design.Unlike prior end-to-end ML methods limited to specific problems,our framework is both load-independent and geometry-independent.This means that a single training session for a constitutive model suffices to tackle various problems directly,eliminating the need for repeated data collection or training.We demonstrate the efficacy and efficiency of this framework using metamaterials with designable elliptical holes or lattice honeycombs microstructures.Leveraging accelerated forward prediction,we can precisely customize the stiffness and shape of metamaterials under diverse loading scenarios,and extend this capability to multi-objective customization seamlessly.Moreover,we achieve topology optimization for stress alleviation at the crack tip,resulting in a significant reduction of Mises stress by up to 41.2%and yielding a theoretical interpretable pattern.This framework offers a general,efficient and precise tool for analyzing the structure-property relationships of novel metamaterials. 展开更多
关键词 Artificial neural network Multiscale computation Bayesian optimization Inverse design programmable metamaterials
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Programmable array antenna based on nematic liquid crystals for the Ka-band
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作者 WANG Qiang KE Junchen BAI Lin 《Journal of Southeast University(English Edition)》 2025年第1期78-83,共6页
A programmable low-profile array antenna based on nematic liquid crystals(NLCs)is proposed.Each antenna unit comprises a square patch radiating structure and a tunable NLC-based phase shifter capable of achieving a ph... A programmable low-profile array antenna based on nematic liquid crystals(NLCs)is proposed.Each antenna unit comprises a square patch radiating structure and a tunable NLC-based phase shifter capable of achieving a phase shift exceeding 360°with high linearity.First,the above 64 antenna units are periodically arranged into an 8×8 NLC-based antenna array,and the bias voltage of the NLC-based phase shifter loaded on the antenna unit is adjusted through the control of the field-programmable gate array(FPGA)programming sequences.This configuration enables precise phase changes for all 64 channels.Numerical simulation,sample processing,and experimental measurements of the antenna array are conducted to validate the performance of the antenna.The numerical and experimental results demonstrate that the proposed antenna performs well within the frequency range of 19.5-20.5 GHz,with a 3 dB relative bandwidth of 10%and a maximum main lobe gain of 14.1 dBi.A maximum scanning angle of±34°is achieved through the adjustment of the FPGA programming sequence.This NLC-based programmable array antenna shows promising potential for applications in satellite communication. 展开更多
关键词 array antenna nematic liquid crystals electronically beam scanning field programmable gate array(FPGA)
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