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Price-based time and energy allocation in cognitive radio multiple access networks with energy harvesting

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Science China(Information Sciences) 2017年第10期60卷 258-260页

作者： Ding XU qun li Wireless Communication Key Lab of Jiangsu Province Nanjing University of Posts and Telecommunications

Cognitive radio(CR),a concept that can solve the conflict between spectrum scarcity and low spectrum utilization,has been researched widely recently[1].There are mainly three CR models:interweave,overlay and underlay[... 详细信息

关键词： CBS Price-based time and energy allocation in cognitive radio multiple access networks with energy harvesting

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西藏阿蠓属两新种(双翅目:蠓科)

四川动物 2004年第4期23卷 317-318页

作者：张有植薛群力邓成玉虞以新成都军区疾病预防控制中心成都610021 军事医学科学院五所六室

本文描述了发现于中国西藏的蠓科阿蠓属昆虫两新种 ,分别命名为钩茎阿蠓 (Alluadomyiarostrata)和双刺阿蠓 (A bispinula)。二新种模式标本保存于军事医学科学院医学昆虫标本馆。

关键词：蠓科模式标本双翅目新种医学昆虫描述发现军事医学科学院命名保存

Digital simulation of 3D turbulence wind field of Sutong Bridge based on measured wind spectra

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第2期13卷 91-104页

作者： Hao WANG Zhou-hong ZONG Ai-qun li Teng TONG Jie NIU Wen-ping deng Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education Southeast UniversityNanjing 210096China Key Laboratory of Environmental Impact and Structural Safety in Engineering China University of Mining&TechnologyXuzhou 221116China

Time domain analysis is an essential implement to study the buffeting behavior of long-span bridges for it can consider the non-linear effect which is significant in long-span bridges. The prerequisite of time domain analysis is the accurate description of 3D turbulence winds. In this paper, some hypotheses for simplifying the 3D turbulence simulation of long-span cable-stayed bridges are conducted, considering the structural characteristics. The turbulence wind which is a 3D multivariate stochastic vector process is converted into four independent 1D univariate stochastic processes. Based on recorded wind data from structural health monitoring system (SHMS) of the Sutong Bridge, China, the measured spectra expressions are then presented using the nonlinear least-squares fitting method. Turbulence winds at the Sutong Bridge site are simulated based on the spectral representation method and the Fast Fourier transform (FFT) technique, and the relevant results derived from target spectra including measured spectra and recommended spectra are compared. The reliability and accuracy of the presented turbulence simulation method are validated through comparisons between simulated and target spectra (measured and recommended spectra). The obtained turbulence si-mulations can not only serve further analysis of the buffeting behavior of the Sutong Bridge, but references for structural anti-wind design in adjacent regions.

关键词： Turbulence simulation Spectral representation method Fast Fourier transform (FFT) Cable-stayed bridges Struc-tural health monitoring system (SHMS) Power spectral density

面向远程内存图数据库的应用感知分离式存储设计

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计算机科学 2025年第1期52卷 151-159页

作者：李纯羽邓龙李永坤许胤龙中国科学技术大学计算机科学与技术学院合肥230026 高性能计算安徽省重点实验室合肥230026

图数据在各种应用中日益普及,其因涵盖多种实体类型和存在丰富的关联关系而备受关注.对于图数据库用户而言,高效的图查询服务是保障系统性能的关键因素.随着数据量增加,单机图数据库很难满足将所有数据存储在内存中的需求,而分布式图数... 详细信息

图数据在各种应用中日益普及,其因涵盖多种实体类型和存在丰富的关联关系而备受关注.对于图数据库用户而言,高效的图查询服务是保障系统性能的关键因素.随着数据量增加,单机图数据库很难满足将所有数据存储在内存中的需求,而分布式图数据库在拓展性和资源利用率方面受到挑战.基于RDMA的远程内存系统的引入为克服这些挑战提供了一种新的选择,通过分离计算和存储资源,实现了更为灵活的内存使用方式.然而,在使用远程内存的情况下如何最大程度地优化图查询性能成为了当前研究的重点问题.文中首先分析了利用操作系统分页机制透明使用远程内存构建图数据库存在的问题,并在应用层次上设计了远程内存图数据库的存储模型.根据不同数据的特点和访问模式,设计了属性图在远程内存中的存储结构,优化了数据布局和访问路径.实验结果表明,在本地内存受限的情况下,与透明使用远程内存相比,应用感知的设计方式的端到端性能最高提升了12倍.

关键词：图查询图数据库图存储远程内存属性图模型

New development of anodizing process of magnesium alloys

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中国有色金属学会会刊：英文版 2004年第z1期14卷 120-125页

作者： BAI li-qun li Di School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

Magnesium alloy, a kind of environment-friendly material with promising and excellent properties, is a good choice for a number of applications. The research and development of anodizing on magnesium alloys and its ap... 详细信息

关键词： magnesium magnesium alloy anodizing

Promoting osteogenic differentiation in pre-osteoblasts and reducing tibial fracture healing time using functional nanofibers

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Nano Research 2018年第7期11卷 3658-3677页

作者： Gu Cheng Jiajia Chen qun Wang Xuewen Yang Yuet Cheng Zhi li Hu Tu Hongbing deng Zubing li The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education School and Hospital of Stomatology & Department of Oral and Maxillofacial Trauma and Plastic Surgery Wuhan University Stomatological Hospital Wuhan University Wuhan 430079 China Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology School of Resource and Environmental Science Wuhan University Wuhan 430079 China Department of Chemical and Biological Engineering Iowa State University Ames IA 50014 USA

Various composite materials are now used as artificial tissue substitutes, and are defining new frontiers in tissue engineering. In the present study, composite membranes based on silk fibroin （SF） were fabricated to form a synthetic periosteum. The fabricated membranes were physicochemically characterized by their morphology, porosity, biocompatibility, biodegradability, chemical structure, and mechanical properties. Following the addition of polycaprolactone （PCL） to the silk fibers, there was a 3-5-fold increase in the elongation at break compared with the pure silk membranes, and surface wettability was retained. The degradation time of the SF within the membranes was also prolonged by adding PCL. Compared with pure PCL membranes or plastic culture plates, the SF-based membranes significantly enhanced the cellular viability and osteogenic differentiation capability of MC3T3-E1 cells. Higher expression levels of osteogenic differentiation markers （runt-related transcription factor 2 （RUNX2）, alkaline phosphatase （ALP）, and osteopontin （OP）） further supported the use of the SF component in bone-related applications. A non-rigid internal fixation （non-RIF） fracture model that healed via endochondral bone formation was created, and fracture callus samples were collected to perform micro-computed tomography, histolog~ and immunohistochemistry analyses at 8 weeks after surgery. A smaller bone volume accompanied by a mineralized bony callus was observed in SF/PCL membrane-treated rats. Immunohistochemistry also indicated that the SF/PCL membrane-treated rats exhibited increased osteocalcin expression but reduced collagen type X expression. These findings could lead to an alternative strategy for treating comminuted fractures with enhanced intramembranous ossification and reduced endochondral ossification.

关键词： silk fibroin polycaprolactone scaffold bone tissue engineering

Sulfolane‑Based Flame‑Retardant Electrolyte for High‑Voltage Sodium‑Ion Batteries

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Nano-Micro Letters 2025年第2期17卷 498-516页

作者： Xuanlong He Jie Peng Qingyun lin Meng li Weibin Chen Pei liu Tao Huang Zhencheng Huang Yuying liu Jiaojiao deng Shenghua Ye Xuming Yang Xiangzhong Ren Xiaoping Ouyang Jianhong liu Biwei Xiao Jiangtao Hu Qianling Zhang Graphene Composite Research Center College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China Center of Electron Microscopy State Key Laboratory of Silicon and Advanced Semiconductor MaterialsSchool of Materials Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China GRINM(Guangdong)Research Institute for Advanced Materials and Technology FoshanGuangdong 528051People’s Republic of China College of Energy Engineering Zhejiang UniversityHangzhouZhejiang 310027People’s Republic of China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105People’s Republic of China Shenzhen Eigen-Equation Graphene Technology Co.Ltd Shenzhen 518000People’s Republic of China

Sodium-ion batteries hold great promise as next-generation energy storage ***,the high instability of the electrode/electrolyte interphase during cycling has seriously hindered the development of *** particular,an unstable cathode–electrolyte interphase(CEI)leads to successive electrolyte side reactions,transition metal leaching and rapid capacity decay,which tends to be exacerbated under high-voltage ***,constructing dense and stable CEIs are crucial for high-performance *** work reports localized high-concentration electrolyte by incorporating a highly oxidation-resistant sulfolane solvent with non-solvent diluent 1H,1H,5H-octafluoropentyl-1,1,2,2-tetrafluoroethyl ether,which exhibited excellent oxidative stability and was able to form thin,dense and homogeneous *** excellent CEI enabled the O3-type layered oxide cathode NaNi_(1/3)Mn_(1/3)Fe_(1/3)O_(2)(NaNMF)to achieve stable cycling,with a capacity retention of 79.48%after 300 cycles at 1 C and 81.15%after 400 cycles at 2 C with a high charging voltage of 4.2 *** addition,its nonflammable nature enhances the safety of *** work provides a viable pathway for the application of sulfolane-based electrolytes on SIBs and the design of next-generation high-voltage electrolytes.

关键词： Sodium-ion batteries Sulfolane-based electrolyte High voltage Layered oxide cathode Flame retardant

金属掺杂的磷烯对亚甲基蓝的吸附机理:DFT-D研究

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原子与分子物理学报 2025年第3期42卷 52-60页

作者：王群周乃武赵虹林杨丽欣邓壹铭单正莉杨志豪邓良平梅青刚孙玉希绵阳师范学院生态安全与保护四川省重点实验室绵阳621006 绵阳师范学院生命科学与技术学院绵阳621006 绵阳师范学院化学与化学工程学院绵阳621000 绵阳师范学院光致功能材料重点实验室绵阳621006 曲阜师范大学生命有机分析重点实验室山东曲阜273165 北京市食品风味化学重点实验室北京100048

随着工业的发展,染料废水对人类和环境的危害愈加显著,其中偶氮类的亚甲基蓝这种染料废水不仅色度大,而且难以降解.因此设计一种高效且灵敏的吸附剂来去除亚甲基蓝对人类和环境的危害是亟须解决的问题.本研究利用基于色散力校正的密度... 详细信息

随着工业的发展,染料废水对人类和环境的危害愈加显著,其中偶氮类的亚甲基蓝这种染料废水不仅色度大,而且难以降解.因此设计一种高效且灵敏的吸附剂来去除亚甲基蓝对人类和环境的危害是亟须解决的问题.本研究利用基于色散力校正的密度泛函理论(DFT-D)的第一性原理方法探索了本征及掺杂磷烯吸附剂对亚甲基蓝的吸附机理,并详细考察了本征及掺杂Al,Ca,Ti和Fe金属原子后的磷烯对亚甲基蓝吸附的影响.研究结果表明亚甲基蓝初始构型会影响磷烯对其吸附,当亚甲基蓝平躺于磷烯表面时有较大的吸附,且金属原子掺杂显著地影响其对亚甲基蓝的吸附能力,掺杂金属原子均增大了磷烯对亚甲基蓝的吸附.其中吸附能力是Fe掺杂磷烯>Ca掺杂磷烯>Ti掺杂磷烯>Al掺杂磷烯.研究结论对于亚甲基蓝的处理带来了新的指导方向,有望为相关染料废水的检测和去除提供有意义的理论参考.

关键词：亚甲基蓝色散力校正密度泛函理论磷烯掺杂磷烯

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Effective capacity region and power allocation for two-way spectrum sharing cognitive radio networks

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Science China(Information Sciences) 2015年第6期58卷 126-135页

作者： XU Ding li qun Wireless Communication Key Lab of Jiangsu Province Nanjing University of Posts and Telecommunications School of Computer Science and Technology Nanjing University of Posts and Telecommunications

In this paper, we consider a spectrum sharing cognitive radio(CR) network where a pair of twoway secondary users(SUs) is allowed to coexist with a primary user(PU) as long as the interference power received at the PU is below an acceptable limit. Under the interference power constraint, we investigate the effective capacity region for two-way SUs. In particular, we derive a closed-form solution for the power allocation problem to achieve the boundary points of an inner bound on the effective capacity region. We also propose a key parameter referred to as weighted-transmission-interference-ratio(WTIR), which plays a significant role in the power allocation policy. In the proposed power allocation policy, the exclusive transmission of SUs shall be performed if one SU’s WTIR is much larger than the others. That is, the one with much larger WTIR shall be allocated non-zero power and the other one shall be allocated zero power. Otherwise, if the difference of their WTIRs is not significant, the concurrent transmission shall be performed. That is, both SUs shall be allocated non-zero power. It is shown that a loose interference power constraint leads to the concurrent transmission in most situations, while a stringent interference power constraint leads to the exclusive transmission in most situations. It is also shown that for the stringent interference power constraint and loose delay quality-of-service(Qo S) constraint, the proposed power allocation policy is almost optimal and thus the obtained inner bound on the effective capacity region is tight.

关键词： cognitive radio effective capacity delay quality-of-service power allocation two-way