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Leverage or crowd out:the National Independent Innovation Demonstration Zone policies and green innovation efficiency of enterprises
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作者 Haonan He Jiaxin Sun +2 位作者 Richard Samuel Freeman Dehong Li Shanyong Wang 《中国科学技术大学学报》 北大核心 2025年第1期32-44,31,I0001,共15页
The National Independent Innovation Demonstration Zone has been assigned the unique mission of demonstrating and leading national innovation and playing a key supportive role in enhancing green innovation.Based on the... The National Independent Innovation Demonstration Zone has been assigned the unique mission of demonstrating and leading national innovation and playing a key supportive role in enhancing green innovation.Based on the sample data of A-share listed companies in China from 2007 to 2021,we apply a multi-period difference-in-differences model to analyze whether the implementation of the National Independent Innovation Demonstration Zone policies plays a leverage effect or a crowd out effect on the green innovation efficiency of enterprises and systematically test the regulatory mechanism of government grants and media attention in the process of this influence.The empirical results show that the imple-mentation of the National Independent Innovation Demonstration Zone policies has a positive impact on the green innovation efficiency of enterprises and that the green innovation induced by this reform is not the leverage effect of additional R&D investment on the basis of the existing innovation activities of enterprises but rather the result of the reallocation of resources to crowd out existing non-green innovation.It is further found that government grants and media attention positively moderate the positive driving effect of National Independent Innovation Demonstration Zone policies on the green innovation efficiency of enterprises. 展开更多
关键词 National Independent Innovation Demonstration Zone policies green innovation efficiency leverage effect crowd out effect
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The Positive Role of Governance in the Way Environmental Policies Impact Technological Innovation 被引量:1
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作者 Li Shiqi 《学术界》 CSSCI 北大核心 2018年第2期271-282,共12页
Against the backdrop of the knowledge economy, global economy is goingthrough a major transformation. How to alleviate the pressure of resources and the environ-ment and to achieve the sustainable development of the e... Against the backdrop of the knowledge economy, global economy is goingthrough a major transformation. How to alleviate the pressure of resources and the environ-ment and to achieve the sustainable development of the economy has become a global agenda.China' s economy growth has been rapid for decades since the reform and opening up policy,but this has also been a great drain on China' s resources and the environment, which is an ur-gent problem to tackle. In recently years, the Chinese government has launched many environ-mental policies in the hope of encouraging technological innovation to guarantee the sustain-able development of the economy. However, research suggested that technological innovationis negatively correlated with environmental policies in most scenarios. In some cases, the num-ber of technological innovation decreases after policies take effect and increases after a whilelike a U - curve. In order to solve this problem, I decided to analyze the panel data from 80provinces in China between 2008 and 2014 and conclude that local governance can implementenvironmental regulations while having a positive impact on the technological innovation inenterprises. In the conclusion, suggestions are given to local governments on how to better en-force environmental policies. 展开更多
关键词 environmental policies TECHNOLOGICAL innovation GOVERNANCE
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Evolving Thinking and Policies of China's Diplomacy and China-EU Relations
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作者 Dr.YANG Jiemian is President of the Shanghai Institutes for International Studies and President of the Shanghai Association of International Relations 《国际展望》 2009年第3期1-13,122,共14页
Evolutions and readjustment permeate China’s diplomatic policy in the six decades’ history of PRC, thanks to the tremendous changes happened to both the world and PRC. Enormous opportunities and challenges to China ... Evolutions and readjustment permeate China’s diplomatic policy in the six decades’ history of PRC, thanks to the tremendous changes happened to both the world and PRC. Enormous opportunities and challenges to China coincide in the present world. China and EU are rising with bigger role to play in the world, though daunting challenges to bilateral relations beckon. 展开更多
关键词 PRC EU Evolving Thinking and policies of China’s Diplomacy and China-EU Relations
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Availability modelling for periodically inspected systems under mixed maintenance policies 被引量:2
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作者 LI Junliang CHEN Yueliang +2 位作者 ZHANG Yong ZHANG Zhuzhu FAN Weijie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第3期722-730,共9页
The availability of a periodic inspection system under mixed maintenance policies is studied in this paper.To accommodate the characteristic of multiple failure modes for complex systems,the system failures can be div... The availability of a periodic inspection system under mixed maintenance policies is studied in this paper.To accommodate the characteristic of multiple failure modes for complex systems,the system failures can be divided into two failure modes:hard failure and soft failure.When hard failure occurs,the corresponding corrective maintenance will be performed,taking a random time under the perfect maintenance policy;in contrast,if the soft failure is found,the corresponding preventive maintenance will be performed,taking a random time under the imperfect maintenance policy.The dynamic age setback model is adopted for imperfect maintenance,which can accurately reflect the fault characteristics of the degraded system.Then an analytical model for system steady state availability and instantaneous availability are derived.Moreover,the optimal method to maximize the system steady-state availability through adjusting the inspection interval is researched.According to the above research,the optimization of system unit time cost,preventive maintenance intervals and availability is researched.Finally,the developed approach is demonstrated by a numerical example. 展开更多
关键词 AVAILABILITY RELIABILITY maintenance repairable system maintenance policy
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Multi-agent reinforcement learning based on policies of global objective
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作者 张化祥 黄上腾 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第3期676-681,共6页
In general-sum games, taking all agent's collective rationality into account, we define agents' global objective, and propose a novel multi-agent reinforcement learning(RL) algorithm based on global policy. In eac... In general-sum games, taking all agent's collective rationality into account, we define agents' global objective, and propose a novel multi-agent reinforcement learning(RL) algorithm based on global policy. In each learning step, all agents commit to select the global policy to achieve the global goal. We prove this learning algorithm converges given certain restrictions on stage games of learned Q values, and show that it has quite lower computation time complexity than already developed multi-agent learning algorithms for general-sum games. An example is analyzed to show the algorithm' s merits. 展开更多
关键词 Markov games reinforcement learning collective rationality policy.
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Research on Farmers' Response to Microeconomic Policies and Its Impact on Land Degradation in Zhaodong Heilongjiang Province
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作者 JIA Li LI You-hua GUO Dong-qing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2005年第2期182-185,共4页
The livelihoods of farmers are responding to the mioroeconomic policies and result in many changes in the landuse pattern and landscape, and the farmer's attitude to the natural resources conservation, specifically i... The livelihoods of farmers are responding to the mioroeconomic policies and result in many changes in the landuse pattern and landscape, and the farmer's attitude to the natural resources conservation, specifically in the land degradation. In order to find the relationship between the farmers' response to the microeeonomic policies and land degradation, the authors surveyed 120 household in three villages in the black soil zone in Heilongjiang Province. Based on the feedback of the questionnaires, the authors established a model to analyze the impact. The results demonstrated that land degradation was impacted by farmers behaviors in the process of the adjustment of agricultural structures in the city of Zhaodong. And the main factors acted on the land degradation were the agricultural labour education level, the transfer of the labour from agricultural production, the price of the agricultural production materials, and the land scale management. The authors put forward some suggestions for sustainable agriculture based on the analysis on the topic. 展开更多
关键词 microeconomic policy farm household land degradation Heilongjiang Province
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Changes and Development of Home and Community Based Elderly Care Service Policies in China
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作者 Wu Li 《学术界》 CSSCI 北大核心 2020年第8期226-233,共8页
This paper analyzes the current situation of the development of home and community based elderly care service in China,points out the existing problems,and puts forward improvement measures,aiming to deepen the unders... This paper analyzes the current situation of the development of home and community based elderly care service in China,points out the existing problems,and puts forward improvement measures,aiming to deepen the understanding of HCBS and promote the theoretical research and practice of community home-based elderly care service. 展开更多
关键词 home and community based elderly care service policy change DEVELOPMENT
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Research on European rural vitalization policies
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作者 Wei Zeng Yajie Gao 《西部人居环境学刊》 2020年第S01期24-34,共11页
Since the 19 th National Congress of the Communist Party of China,rural vitalization has attracted more and more attention in China.Compared with China,European countries have already experienced the by-product of rur... Since the 19 th National Congress of the Communist Party of China,rural vitalization has attracted more and more attention in China.Compared with China,European countries have already experienced the by-product of rural development bottleneck brought by urbanization.Population loss,imbalance of industrial structure and destruction of rural ecological environment are the main reasons to limit the sustainable development of rural areas.This paper explores the rural vitalization policies of developed countries in Europe,summarizes the relevant rural policies of the European Union in recent years,analyzes typical rural vitalization cases in Europe,and tries to provide references and guidance for rural vitalization in China. 展开更多
关键词 Rural vitalization EUROPEAN Rural development policy Great Britain Sweden
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The research progress and regulation of cosmetic ingredients produced by synthetic biology at home and abroad
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作者 Yunping Lan Zhijie Xie +3 位作者 Chujie Zhao Xiaochun Liu Shiqiong Wang Qiuxing He 《日用化学工业(中英文)》 北大核心 2025年第3期367-380,共10页
The use of synthetic biology technology to develop cosmetic ingredients is attracting widespread attention due to its effectiveness,safety,and environmental friendliness.This article explains the concept of synthetic ... The use of synthetic biology technology to develop cosmetic ingredients is attracting widespread attention due to its effectiveness,safety,and environmental friendliness.This article explains the concept of synthetic biology and its key technologies and current status in the production of cosmetic ingredients.It also briefly analyzes the regulatory approaches to synthetic biology-based cosmetic ingredients in different countries and regions,providing guidance for the management of this field in China.The goal is to ensure product safety,enhance consumer trust,and promote the healthy development of the industry. 展开更多
关键词 synthetic biology cosmetic ingredients regulatory policies
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Mode-switching cooperative defense strategy for the orbit pursuit-evasion-defense game
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作者 Yongshang Wei Tianxi Liu Cheng Wei 《Defence Technology(防务技术)》 2025年第2期272-286,共15页
This paper presents a mode-switching collaborative defense strategy for spacecraft pursuit-evasiondefense scenarios.In these scenarios,the pursuer tries to avoid the defender while capturing the evader,while the evade... This paper presents a mode-switching collaborative defense strategy for spacecraft pursuit-evasiondefense scenarios.In these scenarios,the pursuer tries to avoid the defender while capturing the evader,while the evader and defender form an alliance to prevent the pursuer from achieving its goal.First,the behavioral modes of the pursuer,including attack and avoidance modes,were established using differential game theory.These modes are then recognized by an interactive multiple model-matching algorithm(IMM),that uses several smooth variable structure filters to match the modes of the pursuer and update their probabilities in real time.Based on the linear-quadratic optimization theory,combined with the results of strategy identification,a two-way cooperative optimal strategy for the defender and evader is proposed,where the evader aids the defender to intercept the pursuer by performing luring maneuvers.Simulation results show that the interactive multi-model algorithm based on several smooth variable structure filters perform well in the strategy identification of the pursuer,and the cooperative defense strategy based on strategy identification has good interception performance when facing pursuers,who are able to flexibly adjust their game objectives. 展开更多
关键词 Cooperative policy Differential games Orbit pursuit-evasion-defense game Mod recognition
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A novel trajectories optimizing method for dynamic soaring based on deep reinforcement learning
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作者 Wanyong Zou Ni Li +2 位作者 Fengcheng An Kaibo Wang Changyin Dong 《Defence Technology(防务技术)》 2025年第4期99-108,共10页
Dynamic soaring,inspired by the wind-riding flight of birds such as albatrosses,is a biomimetic technique which leverages wind fields to enhance the endurance of unmanned aerial vehicles(UAVs).Achieving a precise soar... Dynamic soaring,inspired by the wind-riding flight of birds such as albatrosses,is a biomimetic technique which leverages wind fields to enhance the endurance of unmanned aerial vehicles(UAVs).Achieving a precise soaring trajectory is crucial for maximizing energy efficiency during flight.Existing nonlinear programming methods are heavily dependent on the choice of initial values which is hard to determine.Therefore,this paper introduces a deep reinforcement learning method based on a differentially flat model for dynamic soaring trajectory planning and optimization.Initially,the gliding trajectory is parameterized using Fourier basis functions,achieving a flexible trajectory representation with a minimal number of hyperparameters.Subsequently,the trajectory optimization problem is formulated as a dynamic interactive process of Markov decision-making.The hyperparameters of the trajectory are optimized using the Proximal Policy Optimization(PPO2)algorithm from deep reinforcement learning(DRL),reducing the strong reliance on initial value settings in the optimization process.Finally,a comparison between the proposed method and the nonlinear programming method reveals that the trajectory generated by the proposed approach is smoother while meeting the same performance requirements.Specifically,the proposed method achieves a 34%reduction in maximum thrust,a 39.4%decrease in maximum thrust difference,and a 33%reduction in maximum airspeed difference. 展开更多
关键词 Dynamic soaring Differential flatness Trajectory optimization Proximal policy optimization
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基于深度强化学习的IRS辅助NOMA-MEC通信资源分配优化 被引量:1
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作者 方娟 刘珍珍 +1 位作者 陈思琪 李硕朋 《北京工业大学学报》 CAS CSCD 北大核心 2024年第8期930-938,共9页
为了解决无法与边缘服务器建立直连通信链路的盲区边缘用户卸载任务的问题,设计了一个基于深度强化学习(deep reinforcement learning, DRL)的智能反射面(intelligent reflecting surface, IRS)辅助非正交多址(non-orthogonal multiple ... 为了解决无法与边缘服务器建立直连通信链路的盲区边缘用户卸载任务的问题,设计了一个基于深度强化学习(deep reinforcement learning, DRL)的智能反射面(intelligent reflecting surface, IRS)辅助非正交多址(non-orthogonal multiple access, NOMA)通信的资源分配优化算法,以获得由系统和速率和能源效率(energy efficiency, EE)加权的最大系统收益,从而实现绿色高效通信。通过深度确定性策略梯度(deep deterministic policy gradient, DDPG)算法联合优化传输功率分配和IRS的反射相移矩阵。仿真结果表明,使用DDPG算法处理移动边缘计算(mobile edge computing, MEC)的通信资源分配优于其他几种对比实验算法。 展开更多
关键词 非正交多址(non-orthogonal multiple access NOMA) 智能反射面(intelligent reflecting surface IRS) 深度确定性策略梯度(deep deterministic policy gradient DDPG)算法 移动边缘计算(mobile edge computing MEC) 能源效率(energy efficiency EE) 系统收益
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Efficient cache replacement framework based on access hotness for spacecraft processors
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作者 GAO Xin NIAN Jiawei +1 位作者 LIU Hongjin YANG Mengfei 《中国空间科学技术(中英文)》 CSCD 北大核心 2024年第2期74-88,共15页
A notable portion of cachelines in real-world workloads exhibits inner non-uniform access behaviors.However,modern cache management rarely considers this fine-grained feature,which impacts the effective cache capacity... A notable portion of cachelines in real-world workloads exhibits inner non-uniform access behaviors.However,modern cache management rarely considers this fine-grained feature,which impacts the effective cache capacity of contemporary high-performance spacecraft processors.To harness these non-uniform access behaviors,an efficient cache replacement framework featuring an auxiliary cache specifically designed to retain evicted hot data was proposed.This framework reconstructs the cache replacement policy,facilitating data migration between the main cache and the auxiliary cache.Unlike traditional cacheline-granularity policies,the approach excels at identifying and evicting infrequently used data,thereby optimizing cache utilization.The evaluation shows impressive performance improvement,especially on workloads with irregular access patterns.Benefiting from fine granularity,the proposal achieves superior storage efficiency compared with commonly used cache management schemes,providing a potential optimization opportunity for modern resource-constrained processors,such as spacecraft processors.Furthermore,the framework complements existing modern cache replacement policies and can be seamlessly integrated with minimal modifications,enhancing their overall efficacy. 展开更多
关键词 spacecraft processors cache management replacement policy storage efficiency memory hierarchy MICROARCHITECTURE
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Deep reinforcement learning guidance with impact time control
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作者 LI Guofei LI Shituo +1 位作者 LI Bohao WU Yunjie 《Journal of Systems Engineering and Electronics》 CSCD 2024年第6期1594-1603,共10页
In consideration of the field-of-view(FOV)angle con-straint,this study focuses on the guidance problem with impact time control.A deep reinforcement learning guidance method is given for the missile to obtain the desi... In consideration of the field-of-view(FOV)angle con-straint,this study focuses on the guidance problem with impact time control.A deep reinforcement learning guidance method is given for the missile to obtain the desired impact time and meet the demand of FOV angle constraint.On basis of the framework of the proportional navigation guidance,an auxiliary control term is supplemented by the distributed deep deterministic policy gradient algorithm,in which the reward functions are developed to decrease the time-to-go error and improve the terminal guid-ance accuracy.The numerical simulation demonstrates that the missile governed by the presented deep reinforcement learning guidance law can hit the target successfully at appointed arrival time. 展开更多
关键词 impact time deep reinforcement learning guidance law field-of-view(FOV)angle deep deterministic policy gradient
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Web服务安全模型研究与实现 被引量:15
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作者 孟伟 张璟 +1 位作者 李军怀 刘海玲 《计算机工程与应用》 CSCD 北大核心 2006年第26期134-136,共3页
随着Web服务在分布式系统中的广泛应用,安全问题日益突出。论文基于WS-Security和WS-Policy协议,提出一个Web服务安全模型,并在.NET环境下,使用WSE2.0Web服务开发组件实现了该模型。该安全模型灵活、可扩展,既保证了SOAP消息端到端的安... 随着Web服务在分布式系统中的广泛应用,安全问题日益突出。论文基于WS-Security和WS-Policy协议,提出一个Web服务安全模型,并在.NET环境下,使用WSE2.0Web服务开发组件实现了该模型。该安全模型灵活、可扩展,既保证了SOAP消息端到端的安全性,又通过安全策略文件提高了Web服务的互操作性,可满足Web服务应用环境下的安全需求。 展开更多
关键词 WEB服务安全 WS—Security WS—Policy WSE信息管理系统
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基于Policy的网络管理模型的研究与实现 被引量:8
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作者 李拥新 陈鸣 +1 位作者 宋丽华 蒋序平 《计算机研究与发展》 EI CSCD 北大核心 2002年第1期49-54,共6页
基于 policy的网络管理支持管理系统动态扩充 ,得到越来越多的研究与应用 .首先给出了基于 policy的网络管理模型 ,然后定义 policy服务器的体系结构和支持协同的基于 policy的网络管理框架 .管理框架支持管理人员对任务进行分解 ,用 po... 基于 policy的网络管理支持管理系统动态扩充 ,得到越来越多的研究与应用 .首先给出了基于 policy的网络管理模型 ,然后定义 policy服务器的体系结构和支持协同的基于 policy的网络管理框架 .管理框架支持管理人员对任务进行分解 ,用 policy描述子任务 ,然后将 policy分发到 policy服务器 ,由 policy服务器解释执行 .多个域的 policy服务器之间可以发送和接收消息以协调地运行 ,完成全局的管理任务 .管理人员可以动态地对 展开更多
关键词 网络管理 policy服务器 CORBA 计算机网络
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一种用于网络管理的基于逻辑的Policy定义语言 被引量:3
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作者 李拥新 陈鸣 +1 位作者 蒋序平 宋丽华 《计算机研究与发展》 EI CSCD 北大核心 2002年第11期1491-1497,共7页
Policy被越来越多地应用于大型分布式系统的管理 .提出了一种基于逻辑的 Policy定义语言 L PDL ,定义了 L PDL的语法、运行模型和语义 ,为基于 Policy的网络管理提供了一种形式化的框架 .L PDL具有简单的语法规则和与图灵机等价的计算能... Policy被越来越多地应用于大型分布式系统的管理 .提出了一种基于逻辑的 Policy定义语言 L PDL ,定义了 L PDL的语法、运行模型和语义 ,为基于 Policy的网络管理提供了一种形式化的框架 .L PDL具有简单的语法规则和与图灵机等价的计算能力 ,管理人员可以根据实际需要 ,灵活地将系统的解释决策功能用 L PDL语言定义成Policy或封装在系统物理实现代码中 .最后给出了基于 L PDL 的网络管理模型及其原型实现和应用 ,表明 L PDL能很好满足网络管理动态发展的需要 . 展开更多
关键词 网络管理 Policy定义语言 PETRI网 图灵机 协同 计算机网络 LPDL语言
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基于层次结构模型的LLP控制算法设计 被引量:2
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作者 尹逊和 崔庆权 +1 位作者 宋永端 戚君戈 《控制工程》 CSCD 北大核心 2009年第S2期24-27,31,共5页
层次结构模型是混杂系统理论中一种重要的模型,主要是因为它能够更直观地反应混杂系统的本质,以及控制变量、离散事件状态变量和连续状态变量之间的关系和演化过程。针对具有混杂特性的双罐系统,建立了其对应的层次结构模型,并设计了合... 层次结构模型是混杂系统理论中一种重要的模型,主要是因为它能够更直观地反应混杂系统的本质,以及控制变量、离散事件状态变量和连续状态变量之间的关系和演化过程。针对具有混杂特性的双罐系统,建立了其对应的层次结构模型,并设计了合于受控输入是有限控制集的Limited Lookahead Policy(LLP)控制算法,并给出了稳定性的条件。分别在正常情况和故障情况下进行了3个仿真实验,实验结果验证了所建立的模型和算法的有效性和鲁棒性。 展开更多
关键词 层次结构模型 双罐系统 LIMITED LOOKAHEAD POLICY
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金融骨干网的SRv6 Policy研究与应用 被引量:6
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作者 祖立军 袁航 《电信科学》 2020年第8期53-65,共13页
金融骨干网作为金融机构网络基础平台的重要组成部分,在当前国家推进数据中心云化及IPv6的大背景下,金融骨干网技术架构也必然需要优化演进。基于此,研究探索了SRv6 Policy在金融骨干网中的应用。首先针对金融骨干网现状,分析了传统方... 金融骨干网作为金融机构网络基础平台的重要组成部分,在当前国家推进数据中心云化及IPv6的大背景下,金融骨干网技术架构也必然需要优化演进。基于此,研究探索了SRv6 Policy在金融骨干网中的应用。首先针对金融骨干网现状,分析了传统方案存在的问题;随后阐述了SRv6 Policy技术优势及实现原理机制;最后对SRv6 Policy在金融骨干网中的应用及部署方案进行了研究探索,并结合金融机构对骨干网中业务流量的管理策略,针对拥塞避免、路径规划的场景研究给出了可选的智能调优方案,进一步增强了金融骨干网稳定性及流量传输保障能力,初步验证了SRv6 Policy在金融骨干网中应用的可行性。 展开更多
关键词 SRv6 Policy 流量工程 SLA保障 智能调优
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浅谈昌黎县的河豚鱼出口受阻问题以及对策(英文)
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作者 李良艳 《思想战线》 CSSCI 北大核心 2010年第S1期46-48,共3页
The swellfish produce is the leading industry in ChangLi,but since 2006, due to the increasing green trade barrier of swellfish operated by Japan,the swellfish amount have continued to decrease. Especially after the i... The swellfish produce is the leading industry in ChangLi,but since 2006, due to the increasing green trade barrier of swellfish operated by Japan,the swellfish amount have continued to decrease. Especially after the international financial crisis, this industry suffers a shock hit, many breeders quitted.We should carefully consider how to deal with the problem? 展开更多
关键词 ChangLi swellfish EXPORT DIFFICULTIES ALTERNATIVE policies
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