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Stage at diagnosis of colorectal cancer through diagnostic route:Who should be screened? 被引量:10
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作者 Nobukazu Agatsuma Takahiro Utsumi +11 位作者 Yoshitaka Nishikawa Takahiro Horimatsu Takeshi Seta Yukitaka Yamashita Yukari Tanaka Takahiro Inoue Yuki Nakanishi Takahiro Shimizu Mikako Ohno Akane Fukushima Takeo Nakayama Hiroshi Seno 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1368-1376,共9页
BACKGROUND Colorectal cancer(CRC)is a global health concern,with advanced-stage diagnoses contributing to poor prognoses.The efficacy of CRC screening has been well-established;nevertheless,a significant proportion of... BACKGROUND Colorectal cancer(CRC)is a global health concern,with advanced-stage diagnoses contributing to poor prognoses.The efficacy of CRC screening has been well-established;nevertheless,a significant proportion of patients remain unscreened,with>70%of cases diagnosed outside screening.Although identifying specific subgroups for whom CRC screening should be particularly recommended is crucial owing to limited resources,the association between the diagnostic routes and identification of these subgroups has been less appreciated.In the Japanese cancer registry,the diagnostic routes for groups discovered outside of screening are primarily categorized into those with comorbidities found during hospital visits and those with CRC-related symptoms.AIM To clarify the stage at CRC diagnosis based on diagnostic routes.METHODS We conducted a retrospective observational study using a cancer registry of patients with CRC between January 2016 and December 2019 at two hospitals.The diagnostic routes were primarily classified into three groups:Cancer screening,follow-up,and symptomatic.The early-stage was defined as Stages 0 or I.Multivariate and univariate logistic regressions were exploited to determine the odds of early-stage diagnosis in the symptomatic and cancer screening groups,referencing the follow-up group.The adjusted covariates were age,sex,and tumor location.RESULTS Of the 2083 patients,715(34.4%),1064(51.1%),and 304(14.6%)belonged to the follow-up,symptomatic,and cancer screening groups,respectively.Among the 2083 patients,CRCs diagnosed at an early stage were 57.3%(410 of 715),23.9%(254 of 1064),and 59.5%(181 of 304)in the follow-up,symptomatic,and cancer screening groups,respectively.The symptomatic group exhibited a lower likelihood of early-stage diagnosis than the follow-up group[P<0.001,adjusted odds ratio(aOR),0.23;95%confidence interval(95%CI):0.19-0.29].The likelihood of diagnosis at an early stage was similar between the follow-up and cancer screening groups(P=0.493,aOR for early-stage diagnosis in the cancer screening group vs follow-up group=1.11;95%CI=0.82-1.49).CONCLUSION CRCs detected during hospital visits for comorbidities were diagnosed earlier,similar to cancer screening.CRC screening should be recommended,particularly for patients without periodical hospital visits for comorbidities. 展开更多
关键词 Colorectal neoplasms Cancer registry Diagnostic route Cancer screening Stage at diagnosis
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Efficient Route Planning for Real-Time Demand-Responsive Transit
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作者 Hongle Li SeongKi Kim 《Computers, Materials & Continua》 SCIE EI 2024年第4期473-492,共20页
Demand Responsive Transit (DRT) responds to the dynamic users’ requests without any fixed routes and timetablesand determines the stop and the start according to the demands. This study explores the optimization of d... Demand Responsive Transit (DRT) responds to the dynamic users’ requests without any fixed routes and timetablesand determines the stop and the start according to the demands. This study explores the optimization of dynamicvehicle scheduling and real-time route planning in urban public transportation systems, with a focus on busservices. It addresses the limitations of current shared mobility routing algorithms, which are primarily designedfor simpler, single origin/destination scenarios, and do not meet the complex demands of bus transit systems. Theresearch introduces an route planning algorithm designed to dynamically accommodate passenger travel needsand enable real-time route modifications. Unlike traditional methods, this algorithm leverages a queue-based,multi-objective heuristic A∗ approach, offering a solution to the inflexibility and limited coverage of suburbanbus routes. Also, this study conducts a comparative analysis of the proposed algorithm with solutions based onGenetic Algorithm (GA) and Ant Colony Optimization Algorithm (ACO), focusing on calculation time, routelength, passenger waiting time, boarding time, and detour rate. The findings demonstrate that the proposedalgorithmsignificantly enhances route planning speed, achieving an 80–100-fold increase in efficiency over existingmodels, thereby supporting the real-time demands of Demand-Responsive Transportation (DRT) systems. Thestudy concludes that this algorithm not only optimizes route planning in bus transit but also presents a scalablesolution for improving urban mobility. 展开更多
关键词 Autonomous bus route planning real-time dynamic route planning path finding DRT bus route optimization sustainable public transport
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CoopAI-Route: DRL Empowered Multi-Agent Cooperative System for Efficient QoS-Aware Routing for Network Slicing in Multi-Domain SDN
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作者 Meignanamoorthi Dhandapani V.Vetriselvi R.Aishwarya 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2449-2486,共38页
The emergence of beyond 5G networks has the potential for seamless and intelligent connectivity on a global scale.Network slicing is crucial in delivering services for different,demanding vertical applications in this... The emergence of beyond 5G networks has the potential for seamless and intelligent connectivity on a global scale.Network slicing is crucial in delivering services for different,demanding vertical applications in this context.Next-generation applications have time-sensitive requirements and depend on the most efficient routing path to ensure packets reach their intended destinations.However,the existing IP(Internet Protocol)over a multi-domain network faces challenges in enforcing network slicing due to minimal collaboration and information sharing among network operators.Conventional inter-domain routing methods,like Border Gateway Protocol(BGP),cannot make routing decisions based on performance,which frequently results in traffic flowing across congested paths that are never optimal.To address these issues,we propose CoopAI-Route,a multi-agent cooperative deep reinforcement learning(DRL)system utilizing hierarchical software-defined networks(SDN).This framework enforces network slicing in multi-domain networks and cooperative communication with various administrators to find performance-based routes in intra-and inter-domain.CoopAI-Route employs the Distributed Global Topology(DGT)algorithm to define inter-domain Quality of Service(QoS)paths.CoopAI-Route uses a DRL agent with a message-passing multi-agent Twin-Delayed Deep Deterministic Policy Gradient method to ensure optimal end-to-end routes adapted to the specific requirements of network slicing applications.Our evaluation demonstrates CoopAI-Route’s commendable performance in scalability,link failure handling,and adaptability to evolving topologies compared to state-of-the-art methods. 展开更多
关键词 6G MULTI-DOMAIN MULTI-AGENT routING DRL SDN
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Frequency-tunable single-photon router based on a microresonator containing a driven three-level emitter
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作者 黄劲松 胡菁兰 +1 位作者 李艳玲 徐中辉 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期377-381,共5页
We propose a frequency-tunable router of single photons with high routing efficiency, which is constructed by two waveguides mediately linked by a single-mode whispering gallery resonator with a driven three-level emi... We propose a frequency-tunable router of single photons with high routing efficiency, which is constructed by two waveguides mediately linked by a single-mode whispering gallery resonator with a driven three-level emitter. Quantum routing probability in the output port is obtained via the real-space Hamiltonian. By adjusting the resonator–emitter coupling and the drive, the desired continuous central frequencies for the resonance peaks of routing photons can be manipulated nearly linearly, with the assistance of Rabi splitting effect and optical Stark shift. The proposed routing system may provide potential applications in designing other frequency-modulation quantum optical devices, such as multiplexers,filters, and so on. 展开更多
关键词 quantum routing scattering theory optical waveguide MICRORESONATOR
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The Impact of Sea Level Rise on Roadway Design and Evacuation Routes in Delaware
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作者 Jack Palevich Ardeshir Faghri Ahmet Karakurt 《American Journal of Climate Change》 2024年第1期69-82,共14页
As the global temperature continues to increase, the sea level continues to rise at a rapid rate that has never been seen before. This becomes an issue for many facets of life but one of the most impacted is the trans... As the global temperature continues to increase, the sea level continues to rise at a rapid rate that has never been seen before. This becomes an issue for many facets of life but one of the most impacted is the transportation infrastructure. Many people living in low elevation coastal areas can become trapped by flooding with no way in or out. With Delaware being a coastal state, this would affect a large portion of the population and will have detrimental effects over time if nothing is done to combat sea level rise. The issue with sea level rise in transportation is that once the roads become flooded, they become virtually unusable and detour routes would be needed. If all the roads in a coastal area were to be affected by sea level rise, the options for detours would become limited. This article looks at direct solutions to combat sea level rise and indirect solutions that would specifically help transportation infrastructure and evacuation routes in Delaware. There is not one solution that can fix every problem, so many solutions are laid out to see what is applicable to each affected area. Some solutions include defense structures that would be put close to the coast, raising the elevation of vulnerable roads throughout the state and including pumping stations to drain the water on the surface of the road. With an understanding of all these solutions around the world, the ultimate conclusion came in the form of a six-step plan that Delaware should take in order to best design against sea level rise in these coastal areas. 展开更多
关键词 Sea Level Rise Roadway Design Evacuation routes
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Red Study Greenway Route Selection at County Scale: A Case Study of Ji’an County, Jiangxi Province, China
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作者 ZHOU Linyue MAO Wei +1 位作者 ZHOU Jingning ZHU Xiaogang 《Journal of Landscape Research》 2024年第5期68-70,76,共4页
Using multi-source data like remote sensing images,resource point coordinates,road networks and land type,a suitability assessment system for red study greenway route selection is constructed with red study resource l... Using multi-source data like remote sensing images,resource point coordinates,road networks and land type,a suitability assessment system for red study greenway route selection is constructed with red study resource layer,traffic condition layer,ecological condition layer,and service radius layer as the selection elements.Analytic Hierarchy Process(AHP)and Delphi method aree used to determine the selection factors and weight allocation of each element,and the single factor evaluation and multi factor overlaying analysis are used to accurately identify suitable selection corridors.The potential position is determined based on the lowest cost path.Finally,the final red study greenway is obtained through manual optimization based on the current situation of the road network.The analysis results show that the areas with the highest suitability were those with the richest distribution of first,second,and third level red study resources.An effective connection of red resource points and various elements helps to enhance the competitiveness of red study tours in Ji’an County,providing a realistic path for selecting study greenways for cities rich in red resources. 展开更多
关键词 Red study greenway route selection Multi-source data Suitability assessment Indicator system
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The Influence of Price Discrimination from Airports on the Route Development Behavior of Airlines
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作者 Daniel Schnitzler 《Journal of Civil Engineering and Architecture》 2024年第1期17-29,共13页
Given the prominence and magnitude of airport incentive schemes,it is surprising that literature hitherto remains silent as to their effectiveness.In this paper,the relationship between airport incentive schemes and t... Given the prominence and magnitude of airport incentive schemes,it is surprising that literature hitherto remains silent as to their effectiveness.In this paper,the relationship between airport incentive schemes and the route development behavior of airlines is analyzed.Because of rare and often controversial findings in the extant literature regarding relevant influencing variables for attracting airlines at an airport,expert interviews are used as a complement to formulate testable hypotheses in this regard.A fixed effects regression model is used to test the hypotheses with a dataset that covers all seat capacity offered at the 22 largest German commercial airports in the week 46 from 2004 to 2011.It is found that incentives from primary choice,as well as secondary choice airports,have a significant influence on Low Cost Carriers.Furthermore,Low Cost Carriers,in general,do not leave any of both types of airports when the incentives cease.In the case of Network Carriers,no case is found where one joins a primary choice airport and receives an incentive.Insufficient data between Network Carriers and secondary choice airports in the time when incentives have ceased means that no statement can be given. 展开更多
关键词 AIRLINE rout development price discrimination
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Manual Order Picking Route Optimization in Distribution Warehouse of Chain Furniture Retail Enterprise
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作者 Yongzhen Zeng Junkun Wang +1 位作者 Ching-Kuei Kao King-Zoo Tang 《American Journal of Operations Research》 2024年第3期105-136,共32页
Due to the effects of the COVID-19 pandemic and the rise of online shopping, the offline sales of IKEA Fuzhou have been declining since 2020. Because the cost of distribution warehouse is a major expense for offline c... Due to the effects of the COVID-19 pandemic and the rise of online shopping, the offline sales of IKEA Fuzhou have been declining since 2020. Because the cost of distribution warehouse is a major expense for offline chain furniture retailers, and the picking process is a key activity in distribution warehouse operations. To reduce the cost of distribution warehouse and alleviate the survival pressure of the offline chain furniture retailers, this paper focuses on optimizing the picking route of the IKEA Fuzhou distribution warehouse. It starts by creating a two-dimensional coordinate system for the storage location of the distribution warehouse using the traditional S-type picking strategy to calculate the distance and time of the sorting route. Then, the problem of optimizing the picking route is then transformed into the travelling salesman problem (TSP), and picking route optimization model is developed using a genetic algorithm to analyze the sorting efficiency and picking route optimization. Results show that the order-picking route using the genetic algorithm strategy is significantly better than the traditional S-type picking strategy, which can improve overall sorting efficiency and operations, reduce costs, and increase efficiency. Thus, this establishes an implementation process for the order-picking path based on genetic algorithm optimization to improve overall sorting efficiency and operations, reduce costs, increase efficiency, and alleviate the survival pressure of pandemic-affected enterprises. 展开更多
关键词 S-Shaped Picking Strategy Picking route Traveling Salesman Problem Genetic Algorithm
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Track Bed Total Route Evaluation for Track Renewals&Asset Management“A Network Rail Perspective”
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作者 Peter Musgrave 《Journal of Traffic and Transportation Engineering》 2024年第5期238-247,共10页
Over the last 10 years there have been significant developments and improvements in the understanding of railway track bed in the UK and its relationship and impact on track quality,ballast life and maintenance follow... Over the last 10 years there have been significant developments and improvements in the understanding of railway track bed in the UK and its relationship and impact on track quality,ballast life and maintenance following track renewals.This paper aims to describe the process adopted by Network Rail for track bed investigation and design which offers Network Rail optimum design solutions and value for money from an investigation and construction perspective,balancing design with possession availability to maximise construction output.It also describes innovative investigation and construction techniques that have been developed over the last 5 years maximising the use of rail mounted asset condition data collection systems which run at line speed,allowing targeted investigations and in some case removing the requirements for physical site investigation.It also allows Network Rail to predict sections of track bed which may be affected by line speed increases which would cause the track bed to fail prematurely or,retain its ability to maintain good track geometry post line speed increase.These problems can manifest themselves as stiffness related problems such as critical velocity issues(surface wave velocity,Rayleigh Wave velocity)or,sub-grade erosion resulting in high rates of deterioration in the vertical track geometry.The paper also describes the development and installation process for Enhanced Axial Micropiles to address stiffness related track bed problems whilst leaving the track in-situ a technique which is new to the UK railways. 展开更多
关键词 Track bed data analysis route evaluation asset management track bed piling and design
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An ICN-Oriented Name-Based Routing Scheme
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作者 Sun Yanbin Zhang Yu +2 位作者 Zhang Hongli Fang Binxing Shi Jiantao 《国际计算机前沿大会会议论文集》 2015年第1期30-32,共3页
Information-Centric Networking (ICN) treat contents as the first class citizens and adopt content names for routing. However, ICN faces challenges of big data. The massive content names and location-independent naming... Information-Centric Networking (ICN) treat contents as the first class citizens and adopt content names for routing. However, ICN faces challenges of big data. The massive content names and location-independent naming bring scalability and efficiency challenges for content addressing. A scalable and efficient name-based routing scheme is a critical component for ICN. This paper proposes a novel Scalable Name-based Geometric Routing scheme, SNGR. To resolve the location-independent names to locations, SNGR utilizes a bi-level sloppy grouping design. To provide scalable location-dependent routing for name resolution, SNGR proposess a universal geometric routing framework. Our theoretical analyses guarantee the performance of SNGR. The experiments by simulation show that SNGR outperformances other similar routing schemes in terms of the scalability of routing table, the reliability to failures, as well as path stretch and latency in name resolution. 展开更多
关键词 name-based routING routING SCALABILITY Information-Centric Networking
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A Fast and Efficient Global Router for Congestion Optimization 被引量:2
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作者 许静宇 鲍海云 +3 位作者 洪先龙 蔡懿慈 经彤 顾钧 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第2期136-142,共7页
An efficient parallel global router using random optimization that is independent of net ordering is proposed.Parallel approaches are described and strategies guaranteeing the routing quality are discussed.The wire le... An efficient parallel global router using random optimization that is independent of net ordering is proposed.Parallel approaches are described and strategies guaranteeing the routing quality are discussed.The wire length model is implemented on multiprocessor,which enables the algorithm to approach feasibility of large scale problems.Timing driven model on multiprocessor and wire length model on distributed processors are also presented.The parallel algorithm greatly reduces the run time of routing.The experimental results show good speedups with no degradation of the routing quality. 展开更多
关键词 global routing congestion optimizing global routing graph (GRG) parallel algorithm
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Modeling commuters' route choice behavior under pre-trip information system 被引量:2
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作者 李春燕 陈峻 +1 位作者 叶晓飞 郑竞恒 《Journal of Southeast University(English Edition)》 EI CAS 2012年第3期344-348,共5页
Research about the auto commuter's pre-trip route choice behavior ignores the combined influence of the real-time information and all respondents' historical information in the existing documents.To overcome this sh... Research about the auto commuter's pre-trip route choice behavior ignores the combined influence of the real-time information and all respondents' historical information in the existing documents.To overcome this shortcoming,an approach to describing the pre-trip route choice behavior with the incorporation of the real-time and historical information is proposed.Two types of real-time information are investigated,which are quantitative information and prescriptive information.By using the bounded rationality theory,the influence of historical information on the real-time information reference process is examined first.Estimation results show that the historical information has a significant influence on the quantitative information reference process,but not on the prescriptive information reference process.Then the route choice behavior is modeled.A comparison is also made among three route choice models,one of which does not incorporate the real-time information reference process,while the others do.Estimation results show that the route choice behavior is better described with the consideration of the reference process of both quantitative and prescriptive information. 展开更多
关键词 route choice pre-trip real-time information bounded rationality theory logit model
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Research on the Harmony between Route Design of and Landscapes along Highway 被引量:1
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作者 汤振兴 朱晓娟 《Journal of Landscape Research》 2010年第11期15-19,23,共6页
Through analyzing landscape environment which is the principal factor to be considered in the route design of highway,principles to be followed by the highway route design are proposed,and approaches of maintaining th... Through analyzing landscape environment which is the principal factor to be considered in the route design of highway,principles to be followed by the highway route design are proposed,and approaches of maintaining the harmony between route design and landscape along the highway under different conditions are discussed. 展开更多
关键词 HIGHWAY route design Landscapes ALONG the HIGHWAY HARMONY
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Synthesis and photoluminescence properties of single-crystal ZnO hexagonal pyramids by PEG400-assisted thermal decomposition route 被引量:1
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作者 刘劲松 张朔 +6 位作者 李子全 朱孔军 陈建康 裘进浩 王春花 高雪琴 王莉萍 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2459-2464,共6页
Large-scale synthesis of ZnO hexagonal pyramids was achieved by a simple thermal decomposition route of precursor at 240 oC in the presence of PEG400. The precursor was obtained by room-temperature solid-state grindin... Large-scale synthesis of ZnO hexagonal pyramids was achieved by a simple thermal decomposition route of precursor at 240 oC in the presence of PEG400. The precursor was obtained by room-temperature solid-state grinding reaction between Zn(CH3COO)2-2H2O and Na2CO3. Crystal structure and morphology of the products were analyzed and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). The results of further experiments show that PEG400 has an important role in the formation of ZnO hexagonal pyramids. Difference between the single and double hexagonal pyramid structure may come from the special thermal decomposition reaction. The photoluminescence (PL) spectra of ZnO hexagonal pyramids exhibit strong near-band-edge emission at about 386 nm and weak green emission at about 550 nm. The Raman-active vibration at about 435 cm-1 suggests that the ZnO hexagonal pyramids have high crystallinity. 展开更多
关键词 ZnO hexagonal pyramids thermal decomposition route formation mechanism photoluminescence property
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A Gridless Router Based on Hierarchical PB Corner Stitching Structure
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作者 张轶谦 蔡懿慈 +2 位作者 洪先龙 张雁 谢民 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第2期141-147,共7页
A multi layer gridless area router is reported.Based on corner stitching,this router adopts tile expansion to explore path for each net.A heuristic method that penalizes nodes deviating from the destination is devise... A multi layer gridless area router is reported.Based on corner stitching,this router adopts tile expansion to explore path for each net.A heuristic method that penalizes nodes deviating from the destination is devised to accelerate the algorithm.Besides,an enhanced interval tree is used to manage the intermediate data structure.In order to improve the completion rate of routing,a new gridless rip up and rerouting algorithm is proposed.The experimental results indicate that the completion rate is improved after the rip up and reroute process and the speed of this algorithm is satisfactory. 展开更多
关键词 gridless area routing rip up and reroute corner stitching structure VLSI
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利用RouterOS构建高校图书馆无缝网络办公系统 被引量:7
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作者 苏东出 《现代图书情报技术》 CSSCI 北大核心 2007年第11期84-86,共3页
通过对高校图书馆办公网络现状的调查研究,发现Cernet与不同网络之间的"互联互通"是影响高校图书馆网络办公效率和资源发布、获取的主要因素,分析利用RouterOS来构建安全畅通的图书馆网络办公系统的可行性。实践表明,该方案... 通过对高校图书馆办公网络现状的调查研究,发现Cernet与不同网络之间的"互联互通"是影响高校图书馆网络办公效率和资源发布、获取的主要因素,分析利用RouterOS来构建安全畅通的图书馆网络办公系统的可行性。实践表明,该方案具有投资低、效率高、安全性好、配置灵活等优点。 展开更多
关键词 虚拟保护网 routeROS 网络 双路由 图书馆
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Routes Choice of Urban Agriculture,Ecotourism and Cultural Innovation Industry Fusion
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作者 朱启酒 钱静 《Agricultural Science & Technology》 CAS 2012年第12期2667-2670,共4页
The fusion of urban agriculture, ecotourism and cultural innovation industry has been a necessary way for industry updating, value increase and income im- provement of farmers in suburbs. The methods available of the ... The fusion of urban agriculture, ecotourism and cultural innovation industry has been a necessary way for industry updating, value increase and income im- provement of farmers in suburbs. The methods available of the fusion are as fol- lows: corporation development and operation, led by government with an integrated plan; corporation management and development under guidance of market with sup- port from government; collective development under guidance of market and policies; individual development and operation with the model of "villagers participation de- pending on infrastructure provided by government". The four routes enjoy exclusive advantages and characters. Hence, different villages and towns should adopt the most suitable one according to local conditions for further development and management. 展开更多
关键词 Choice of route Industry fusion Culture innovation ECOTOURISM Urbanagriculture
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用WIN2000 Route实现子网互联
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作者 陈希球 《长江工程职业技术学院学报》 CAS 2003年第2期49-50,共2页
阐述了IP子网的路由问题,并介绍了用WIN2000 Route 实现子网互联的静态路由的配置方法。
关键词 WIN2000 route 网段 IP路由 路由器
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Microstructure evolution and mechanical properties of ZK60 magnesium alloy produced by SSTT and RAP route in semi-solid state
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作者 王长朋 张营营 +3 位作者 李迪凡 梅华生 张帷 刘杰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3621-3628,共8页
The microstructure evolution and mechanical properties of a ZK60 magnesium alloy produced by the semi-solid thermal transformation (SSTT) route and the recrystallization and partial melting (RAP) route were studie... The microstructure evolution and mechanical properties of a ZK60 magnesium alloy produced by the semi-solid thermal transformation (SSTT) route and the recrystallization and partial melting (RAP) route were studied, respectively. The microstructure evolution during partial remelting was studied at different temperatures for different time. The tensile mechanical properties of thixoformed components by the two routes at room temperature were examined. The results show that coalescence is dominant in the SSTT alloy and Ostwald ripening is dominant in the RAP alloy. Compared with the SSTT route, the RAP route can produce finer semi-solid microstructure under the similar isothermal holding condition. The microstructure of the RAP alloy is much more spheroidized compared with the SSTT alloy. Thixoforming for the ZK60 magnesium alloy produced by the SSTT and RAP route results in successful filling of the die, and the thixoforming process improves the mechanical properties of ZK60 magnesium alloy. The RAP alloy shows significantly advantageous mechanical properties over that of the SSTT alloy. 展开更多
关键词 ZK60 magnesium alloy semi-solid thermal transformation (SSTT) recrystallization and partial melting (RAP) route microstructure evolution mechanical properties
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En-Route Transcoding缓存的优化放置和替换
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作者 李春洪 冯国富 +2 位作者 顾铁成 陆桑璐 陈道蓄 《软件学报》 EI CSCD 北大核心 2008年第4期956-966,共11页
对en-route transcoding缓存中的缓存路由和协同放置及替换问题进行了研究.提出了CCRA(cost-aware cache routing algorithm)缓存路由算法,能以可控的探测开销来发现潜在的、具有最小访问开销的缓存对象.在此基础上,建立了en-route tran... 对en-route transcoding缓存中的缓存路由和协同放置及替换问题进行了研究.提出了CCRA(cost-aware cache routing algorithm)缓存路由算法,能以可控的探测开销来发现潜在的、具有最小访问开销的缓存对象.在此基础上,建立了en-route transcoding缓存的分析模型,将缓存放置和替换问题形式化为一个最优化问题,并利用一种基于动态规划的方法来求解最佳缓存放置策略.仿真结果表明,与已有的元算法放置策略相比,该协同放置和替换策略可以获得更好的CSR性能. 展开更多
关键词 en-route transcoding缓存 缓存路由 协同放置 缓存替换
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