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121.
LIN Qun ZHAO Yong-li CAO Xu-ping YU Xiao-song TANG Ting-ting ZHANG Jie 《中国邮电高校学报(英文版)》2012,19(6):105-112
The granularity of the flexible bandwidth optical network is the spectral slots,which is much smaller than that of the wavelength switch optical network.For the dynamic clients’ connections setup and tear down processes,it will give rise to fragmentation of spectral resources.It is the decline in the probability of finding sufficient contiguous spectrum for new connections that result in the fragmentation of spectral resource.To be more specific,these spectra may be unavailable and waste.In this case,the severe waste of the spectrum will lead to low efficiency in spectral utilization and will not adapt to large capacity requirements of transmission in the future.Because path computation element(PCE) framework has the characteristics of the central disposal and deployment of the spectrum resource,we construct the spectral resource allocation scenario based on PCE framework in the flexible bandwidth optical network to use spectrum resource effectively.Based on the principle of the generation of the fragmentation,we put forward a spectrum resource defragmentation algorithm to consolidate the available spectrum for clients’ connections.The simulation results indicate that this algorithm is able to reduce fragmentation of network,improve the continuity of spectral resource,reduce the blocking rate of services in the network and improve the spectral efficiency significantly. 相似文献
122.
We construct a quantum circuit to produce a task-oriented partially entangled state and use it as the quantum channel for controlled joint remote state preparation. Unlike most previous works, where the parameters of the quantum channel are given to the receiver who can accomplish the task only probabilistically by consuming auxiliary resource, operation and measurement, here we give them to the supervisor. Thanks to the knowledge of the task-oriented quantum channel parameters, the supervisor can carry out proper complete projective measurement, which, combined with the feed-forward technique adapted by the preparers, not only much economizes (simplifies) the receiver's resource (operation) but also yields unit total success probability. Notably, such apparent perfection does not depend on the entanglement degree of the shared quantum channel. Our protocol is within the reach of current quantum technologies. 相似文献
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OKRs(objective&key results,目标与关键性成果)是目前较为先进的企业管理模式,它与传统的KPI(key performance indicator)管理模式最大的区别就是重过程、重沟通、重自律。这些特点使得OKRs管理模式非常适用于研究生的科研管理。在目前国内高校研究生招生规模不断扩大的大背景下,利用OKRs提高研究生管理效率,激发研究生自主学习和科研的热情与激情,进而提高研究生教育质量显得尤为重要。构建了基于OKRs思想的全新研究生科研管理模式,并以“油水分离网膜相关研究”为例进行了案例分析,为研究生的科研管理提供了有效的借鉴与参考。 相似文献
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目前高校实验教学主要存在实验室管理落后、实验效果差、与社会发展脱节、实验室利用率低等问题,本文对如何解决实验教学中出现的问题进行了探讨并给出了解决方案。 相似文献
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本文提出采用信息管理系统加强对水利工程建设进行管理,阐述了信息系统应用于水利工程建设中的必要性,并针对水利工程管理信息系统中存在的问题进行论述,归纳和总结出几点改善措施,希望能够为全面提升水利工程管理工作效率提供保障. 相似文献
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Yiming Liu Stuart W. Bunting Shiming Luo Kunzheng Cai Qiangqiang Yang 《Natural Resource Modeling》2019,32(1)
Inappropriate development and overexploitation have seriously degraded aquatic resources in China. Stakeholders identified three fish stock enhancement and biodiversity conservation scenarios for the Beijiang River: S1, increased fish restocking; S2, no fishing season and habitat conservation; and S3, strict pollution control. Potential impacts of these actions on the livelihoods of fishers were evaluated using applied economic modeling. Baseline costs and benefits came from logbooks from 30 fishers and a survey of 90 households in three villages. The financial net benefit for a household was US$1583 (¥11,160) annually, representing a 142% and 387% return on capital and operating costs, respectively. Larger catches associated with S1 and S2 generated a net benefit of US$1651 and US$1822, respectively. Strict pollution control resulting in higher catches (+20%) and lower operating costs (?20%) would increase the net benefit by 15.9% to US$1835 annually. Pollution control would benefit other resource users and is a prerequisite for ecological restoration. Recommendations for Resource Managers
- Stringent pollution control measures are essential to conserve aquatic biodiversity and enhance the livelihoods of fishers but will require considerable public and private sector investment.
- Enhanced fish stocks in the Beijiang River could benefit poor livelihoods but may not be sufficient to lift households out of poverty, aged fishers require government assistance to diversify their livelihoods, access alternative urban employment, and survive with dignity.
- Adopting the economic modeling approach presented here could enable responsible authorities to simultaneously evaluate fish stock enhancement and biodiversity conservation options.
- Broader application of the approach presented here could help ensure small‐scale inland fisheries are managed sustainably and aquatic ecosystems are restored and protected by 2020, in line with Target 6 of the United Nations’ Convention on Biological Diversity Strategic Plan for Biodiversity.