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基于hops的Internet复杂网络分割度分析 被引量:6
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作者 苏威积 赵海 +1 位作者 徐野 张文波 《通信学报》 EI CSCD 北大核心 2005年第9期1-8,共8页
首先讨论了相同分割度对不同网络传播行为的影响,并以小世界网络为例讨论了不同分割度对相同网络传播行为的影响;定义了基于hops的Internet分割度,根据CAIDA提供的全球范围30个主要monitor5年以来采集的数据,对Internethops进行统计分析... 首先讨论了相同分割度对不同网络传播行为的影响,并以小世界网络为例讨论了不同分割度对相同网络传播行为的影响;定义了基于hops的Internet分割度,根据CAIDA提供的全球范围30个主要monitor5年以来采集的数据,对Internethops进行统计分析,并计算出Internet分割度,与国际该领域研究成果进行相比,更进一步揭示了Internet小世界效应的规律;针对hops与RTT进行了10种模型的回归分析,得出hops与RTT更符合幂函数关系及其关键参数,从统计上证明了Internet复杂网络传播行为的幂率关系,并以此建立了Internet分割度时间敏感性模型(ISTSDM);建立了针对Internet分割度的时间序列随机过程模型(MTSSPISD),并以此讨论了Internet分割度的时间演化规律;最后利用模型ISTSDM和模型MTSSPISD对2008年北京奥运期间Internet分割度和IP层数据平均传播时间进行了预测。 展开更多
关键词 分割度 集群度 特征路径长度 hops RTT 复杂网络 小世界效应
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HOPS复合体蛋白在细胞自噬过程中的功能研究 被引量:1
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作者 胡晚秋 林志祥 +2 位作者 陈丽莲 晏向华 陈放 《中国细胞生物学学报》 CAS CSCD 2011年第8期855-860,共6页
自噬(autophagy)是一种溶酶体依赖性的细胞内降解途径,其主要功能是将生物大分子(蛋白质、多糖等)或细胞器(线粒体等)回收至溶酶体中并将其降解为单糖、氨基酸等小分子以重复利用。发现HOPS复合体中的两个基因vps39和vps41的缺失会导致... 自噬(autophagy)是一种溶酶体依赖性的细胞内降解途径,其主要功能是将生物大分子(蛋白质、多糖等)或细胞器(线粒体等)回收至溶酶体中并将其降解为单糖、氨基酸等小分子以重复利用。发现HOPS复合体中的两个基因vps39和vps41的缺失会导致酵母内GFP-ATG8大量积累。进一步研究表明,积累的原因是GFP-ATG8与液泡不能发生融合。而在HOPS复合体中的另外两个基因vps16和vps18缺失的情况下,自噬融合没有受到影响;在vps16和vps18双敲除的菌株中,自噬融合同样没有受到影响。该实验结果为理解HOPS复合体的功能和自噬体与液泡融合的过程提供了新的线索。 展开更多
关键词 自噬 膜泡融合 hops复合体
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Optimizing Packet Generation Rate for Multiple Hops WBAN with CSMA/CA Based on IEEE802.15.6
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作者 Pham Thanh Hiep Ryuji Kohno 《Communications and Network》 2014年第2期112-123,共12页
Wireless Body Area Network (WBAN) is considered to apply to both medical healthcare and entertainment applications. A requirement for each application is different, i.e. high reliability for medical healthcare whereas... Wireless Body Area Network (WBAN) is considered to apply to both medical healthcare and entertainment applications. A requirement for each application is different, i.e. high reliability for medical healthcare whereas high throughput for entertainment application. However, for both applications, low energy consumption is requested. Multiple hops technics have been researching in many fields of wireless system, e.g., ad hod, mobile, ITS etc. and its energy-efficiency is reported to be high. We propose the multiple hops technic for WBAN, however, WBAN is different to another systems, almost sensors forward the vital data packet of another sensors while sensing and generating the data packet of itself. Therefore, according to a packet generation rate of all sensors, probabilities of successful transmission and packet loss because of collision, timeout and overflow, are changed. It means that the vital data is lost and the transmit power is wasted due to packet loss. In order to obtain the highest throughput and save the power, the successful transmission probability is analyzed and the packet generation rate is optimized for multiple hops WBAN that using CSMA/CA based on IEEE802.15.6. The numerical calculation result indicates that the optimized packet generation rate depends on the system model. Moreover, the relation between the system model, the optimized packet generation rate and the throughput is discussed in the paper. 展开更多
关键词 Multiple hops Body Area Network Optimal PACKET Generation Rate Successful PROBABILITY COLLISION PROBABILITY CSMA/CA of IEEE802.15.6
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Study on Brewing Characteristics of High α-acid and High β-acid Hops
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作者 Yanwei GUO Cong NIE +2 位作者 Xueqin GUAN Jie ZHANG Guiheng YANG 《Agricultural Biotechnology》 CAS 2019年第2期185-187,190,共4页
[Objectives] Columbus and Tsingtao Flower were selected to brew Ale beer, thereby studying the brewing characteristics of high α-acid and high β-acid content hops. [Methods] The content of diacetyl and bitterness in... [Objectives] Columbus and Tsingtao Flower were selected to brew Ale beer, thereby studying the brewing characteristics of high α-acid and high β-acid content hops. [Methods] The content of diacetyl and bitterness in beer were determined by a spectrophotometer at 335 and 275 nm, respectively. With pH=8.2 as the end point of potentiometric titration, the total acid content in beer was calculated by acid-base titration method, and sensory evaluation for beer was conducted. [Results] The results show that α-acid is an important factor affecting the production and reduction rate of diacetyl in beer. The production and reduction rate of diacetyl in high α-acid hops were lower than those in high β-acid hops; iso-α-acid was the main source of bitterness in beer, and high α-acid hops had more significant bitter value than high β-acid hops; and malt acid compounds and fermentation production were the main source of total acid in beer, and high α-acid and high β-acid hops had a little effect on total acid in beer. In sensory evaluation, high α-acid hops were more effective than high β-acid hops in terms of zest of the mouthfeel, foaming retention and alcohol fragrance, while in clarity, high α-acid hops were lower than high β-acid hops. [Conclusions] Therefore, we can draw a conclusion that the brewing characteristics of high α-acid hops are better than those of high β-acid hops. 展开更多
关键词 hops HIGH ɑ-acid HIGH β-acid DIACETYL
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CONVERSE HOPS MID世纪球魂
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作者 许大维 《中国服装(北京)》 2008年第8期42-43,共2页
1908年MILLS CONVERSE先生在北卡罗来纳州创立CONVERSE橡胶公司,1910年时胶鞋的日产量已经可以达到4000双,是最畅销休闲鞋。随着篮球运动的发展,1917年CONVERSE公司推出了ALL STAR帆布鞋,标志着专业篮球鞋的诞生,在此后的几十年里... 1908年MILLS CONVERSE先生在北卡罗来纳州创立CONVERSE橡胶公司,1910年时胶鞋的日产量已经可以达到4000双,是最畅销休闲鞋。随着篮球运动的发展,1917年CONVERSE公司推出了ALL STAR帆布鞋,标志着专业篮球鞋的诞生,在此后的几十年里,“ALL STAR”一直是篮球鞋的代名词,广泛活跃在全世界的篮球场上。 展开更多
关键词 hops MID 北卡罗来纳州 STAR 篮球运动 SE公司 篮球鞋 日产量
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Analysis of Hops Length in Wireless Sensor Networks 被引量:4
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作者 Mekkaoui Kheireddine Rahmoun Abdellatif 《Wireless Sensor Network》 2014年第6期109-117,共9页
Wireless sensor networks are provided with a limited source of power. The lifetime of such networks is an overwhelming matter in most network applications. This lifetime depends strongly on how efficiently such energy... Wireless sensor networks are provided with a limited source of power. The lifetime of such networks is an overwhelming matter in most network applications. This lifetime depends strongly on how efficiently such energy is distributed over the nodes especially during transmitting and receiving data. Each node may route messages to destination nodes either through short hops or long hops. Optimizing the length of these hops may save energy, and therefore extend the lifetime of WSNs. In this paper, we propose a theorem to optimize the hop’s length so to make WSN power consumption minimal. The theorem establishes a simple condition on hop’s length range. Computer simulation when performing such condition on Mica2 sensors and Mica2dot sensors reveals good performance regarding WSNs energy consumption. 展开更多
关键词 Wireless Sensor NETWORKS Energy Efficiency MULTI-HOP ROUTING HOP LENGTH Network’s Life Time
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氢基质膜曝气生物膜反应器去除卤代有机污染物的研究进展
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作者 何俊霞 周经洲 夏四清 《水处理技术》 北大核心 2025年第4期1-7,共7页
卤代有机污染物(HOPs)广泛存在于水体环境,因其持久性、生物累积性和毒性而对生态安全和人类健康造成重大威胁。因此,探寻水体中HOPs去除的新方法具有重要意义。氢基质膜曝气生物膜反应器(H_(2)-MBf R)技术结合中空纤维膜无泡曝气和氢... 卤代有机污染物(HOPs)广泛存在于水体环境,因其持久性、生物累积性和毒性而对生态安全和人类健康造成重大威胁。因此,探寻水体中HOPs去除的新方法具有重要意义。氢基质膜曝气生物膜反应器(H_(2)-MBf R)技术结合中空纤维膜无泡曝气和氢自养还原,因经济高效、中间产物毒性较低、可同步去除多种污染物等优势而颇受关注,在HOPs降解方面的研究也逐渐增多。本文总结H_(2)-MBf R去除HOPs的实验室研究,系统梳理H_(2)-MBf R对多种HOPs的降解效能以及影响HOPs去除效率的关键因素,阐述HOPs降解的具体机理和涉及的优势微生物,简略分析该技术面临的挑战与对应的解决措施,期望为H_(2)-MBf R的工程化应用与推广提供理论支撑和参考基础。 展开更多
关键词 卤代有机污染物(hops) 氢基质膜曝气生物膜反应器(H_(2)-MBfR) 影响因素 降解机理
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恒电位电解法制备光致发光掺钬多孔硅 被引量:1
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作者 龚孟濂 曾春莲 +3 位作者 黄伟国 谢国伟 郑婉华 廉德亮 《中国稀土学报》 CAS CSCD 北大核心 1998年第2期126-130,共5页
研究了一种新的多孔硅掺稀土的电化学方法———恒电位电解,以及稀土硝酸盐支持电解质有机溶剂的新电解体系。这一方法和体系的特点是通过采用适当外加电压来控制电解产物,提高掺入的稀土浓度,提高发光强度,同时避免生成导致发... 研究了一种新的多孔硅掺稀土的电化学方法———恒电位电解,以及稀土硝酸盐支持电解质有机溶剂的新电解体系。这一方法和体系的特点是通过采用适当外加电压来控制电解产物,提高掺入的稀土浓度,提高发光强度,同时避免生成导致发光不稳定的产物,提高发光稳定性。优化了阳极氧化制备多孔硅的条件和阴极还原制备掺钬多孔硅的条件(钬化合物浓度、溶剂、离子强度、电解电压、时间),获得光致发光强度高于多孔硅的掺钬多孔硅。对多孔硅和掺钬多孔硅的光致发光机制进行了讨论。 展开更多
关键词 掺钬 多孔硅 恒电位电解 制备 光致发光 hops
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Interplay between the Pseudogap and Superconductivity in Doped Mott Insulators:a Cluster Dynamical Mean-Field Theory Study
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作者 Jinbin Liu Dao-Xin Yao Wei Wu 《Chinese Physics Letters》 2025年第8期264-269,共6页
We investigate the interplay between the pseudogap state and d-wave superconductivity in the two-dimensional doped Hubbard model by employing an eight-site cluster dynamical mean-field theory method.By tuning electron... We investigate the interplay between the pseudogap state and d-wave superconductivity in the two-dimensional doped Hubbard model by employing an eight-site cluster dynamical mean-field theory method.By tuning electron hopping parameters,the strong-coupling pseudogap in the two-dimensional Hubbard model can be either enhanced or suppressed in the doped Mott insulator regime.We find that in underdoped cases,the closing of pseudogap leads to a significant enhancement of superconductivity,indicating competition between the two in the underdoped regime.In contrast,at large dopings,suppressing the pseudogap is accompanied by a concurrent decrease in the superconducting transition temperature Tc,which can be attributed to a reduction in antiferromagnetic correlations behind both the pseudogap and superconductivity.We elucidate this evolving relationship between pseudogap and superconductivity across different doping regimes. 展开更多
关键词 doped mott insulator regimewe PSEUDOGAP tuning electron hopping parametersthe closing pseudogap doped mott insulators competition b cluster dynamical mean field theory electron hopping
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Peru's rappers have the world taking notice
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作者 邓云 《疯狂英语(新悦读)》 2025年第4期19-24,75,76,共8页
1 It's a sunny afternoon in Juliaca,a city near Lake Titicaca,Peru.Among the thousands of native Quechua people gathering in the town square is a man dressed in black on a black horse.He's dressed in memory of... 1 It's a sunny afternoon in Juliaca,a city near Lake Titicaca,Peru.Among the thousands of native Quechua people gathering in the town square is a man dressed in black on a black horse.He's dressed in memory of the country's most respected figure:Túpac AmaruⅡ,a native leader who led a war against the Spanish Empire and became a symbol for the fighting spirits in the Andes.He's also there to rap.From horseback,Cay Sur performs his song about heroes,its hip⁃hop beat pulsing(洋溢)through the crowd. 展开更多
关键词 ANDES native quechua people T pac Amaru II Rap culture Peru hip hop QUECHUA
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A Dynamic SDN-Based Address Hopping Model for IoT Anonymization
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作者 Zesheng Xi Chuan He +1 位作者 Yunfan Wang Bo Zhang 《Computer Modeling in Engineering & Sciences》 2025年第8期2545-2565,共21页
The increasing reliance on interconnected Internet of Things(IoT)devices has amplified the demand for robust anonymization strategies to protect device identities and ensure secure communication.However,traditional an... The increasing reliance on interconnected Internet of Things(IoT)devices has amplified the demand for robust anonymization strategies to protect device identities and ensure secure communication.However,traditional anonymization methods for IoT networks often rely on static identity models,making them vulnerable to inference attacks through long-term observation.Moreover,these methods tend to sacrifice data availability to protect privacy,limiting their practicality in real-world applications.To overcome these limitations,we propose a dynamic device identity anonymization framework using Moving Target Defense(MTD)principles implemented via Software-Defined Networking(SDN).In our model,the SDN controller periodically reconfigures the network addresses and routes of IoT devices using a constraint-aware backtracking algorithmthat constructs new virtual topologies under connectivity and performance constraints.This address-hopping scheme introduces continuous unpredictability at the network layer dynamically changing device identifiers,routing paths,and even network topology which thwarts attacker reconnaissance while preserving normal communication.Experimental results demonstrate that our approach significantly reduces device identity exposure and scan success rates for attackers compared to static networks.Moreover,the dynamic schememaintains high data availability and network performance.Under attack conditions it reduced average communication delay by approximately 60% vs.an unprotected network,with minimal overhead on system resources. 展开更多
关键词 Device anonymization address hopping moving target defense software defined networking cyber resilience
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Dynamic Spectrum Sharing Method for Satellite Network and Cellular Network Based on Beam-Hopping
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作者 Deng Wei Zhang Ximu +4 位作者 Du Qin Ge Ning Cheng Jinxia Ma Ke Zhao Lin 《China Communications》 2025年第12期92-107,共16页
The integration of satellite communication network and cellular network has a great potential to enable ubiquitous connectivity in future communication networks.Among numerous related application scenarios,the direct ... The integration of satellite communication network and cellular network has a great potential to enable ubiquitous connectivity in future communication networks.Among numerous related application scenarios,the direct connection of mobile phone to satellite has attracted increasing attention.However,the spectrum scarcity in the sub-6 GHz band and low spectrum utilization prevents its popularity.To address these problem,in this paper,we propose a dynamic spectrum sharing method for satellite network and cellular network based on beam-hopping.Specifically,we first develop a centralized dynamic spectrum sharing architecture based on beam-hopping,and propose a delay pre-compensation scheme for beam hopping pattern.Then,an optimization problem is formulated to maximize the overall capacity of the integrated network,with considering the service requirements,the fairness between beam positions and mixed co-channel interference,etc.To solve this problem,a polling-based dynamic resource allocation algorithm is proposed.Simulation results confirm that the proposed algorithm can effectively reduce the serious cochannel interference between different beams or different systems,and improve the spectrum utilization rate as well as system capacity. 展开更多
关键词 beam hopping co-channel interference delay pre-compensation dynamic spectrum sharing integrated satellite-terrestrial networks
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HPMG: A High-Performance MTD Gateway Framework
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作者 He Weizhen Chen Fucai +3 位作者 Cheng Guozhen Zhou Dacheng Shang Ke Yang Chunfang 《China Communications》 2025年第10期223-237,共15页
End-host address mutation is one of the key network moving target defense mechanisms to defend against reconnaissance.However,frequently changing host addresses increases the transmission de-lay of active sessions,whi... End-host address mutation is one of the key network moving target defense mechanisms to defend against reconnaissance.However,frequently changing host addresses increases the transmission de-lay of active sessions,which may cause serious ram-ifications.In this paper,by leveraging the advanced DPDK technology,we proposed a high-performance MTD gateway framework,called HPMG,which can not only prevent adversaries from reconnaissance ef-fectively,but also retain high-speed data packet pro-cessing capabilities.Firstly,every moving target host is assigned three different IP addresses,called real IP,virtual IP,and external IP,to realize multi-level net-work address architecture.To delay the scanning tech-niques of adversaries,HPMG mutates virtual IP and virtual MAC addresses,and replies with fake host re-sponses.Besides,to be transparent to the end-hosts,HPMG keeps real IP and real MAC unchanged.Fi-nally,we optimized the forwarding and processing performance of the HPMG based on the fast path framework of DPDK.Our theoretical analysis,imple-mentation,and evaluation show that HPMG can effec-tively defend against reconnaissance attacks and de-crease the processing delay caused by address muta-tion. 展开更多
关键词 cyber scanning data plane development kit IP hopping moving target defense network ad-dress mutation
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Performance Evaluation and Transmitter Optimization for AN-Aided FH Communication Against Time Misalignment
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作者 Song Changqing Lin Lang +3 位作者 Qin Lizhi Xiao Fei Zhao Hongzhi Shao Shihai 《China Communications》 2025年第3期86-103,共18页
To guarantee secure communication against eavesdropping and malicious attack,an artificial noise(AN)-aided frequency-hopping(FH)architecture is adopted in this article.But the inevitable time misalignment between the ... To guarantee secure communication against eavesdropping and malicious attack,an artificial noise(AN)-aided frequency-hopping(FH)architecture is adopted in this article.But the inevitable time misalignment between the received signal and locally reconstructed AN will deteriorate the AN cancellation performance,yielding significant secrecy degradation at the FH receiver.In view of this,first,the AN cancellation performance under time misalignment is evaluated via signal to AN-plus-noise ratio,and the system secrecy is analyzed via secrecy rate.Then,to mitigate the performance degradation raised by time misalignment,the transmitting power allocation scheme for AN and confidential signal(CS)is optimized,and the optimal hopping period is designed.Notably,the obtained conclusions in both the performance evaluation and transmitter optimization sections hold no matter whether the eavesdropper can realize FH synchronization or not.Simulations verify that time misalignment will raise non-negligible performance degradation.Besides,the power ratio of AN to CS should decrease as time misalignment increases,and for perfect time synchronization,the transmitting power of AN and CS should be equivalent.In addition,a longer hopping period is preferred for secrecy enhancement when time misalignment gets exacerbated. 展开更多
关键词 artificial noise(AN)cancellation hopping period design power allocation time misalignment
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Entanglement Signatures of(2+1)D Dirac Fermions Subjected to Randomness
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作者 Qijie Zhang Weiwei Chen +2 位作者 Wei Li Qunxiang Li W.Zhu 《Chinese Physics Letters》 2025年第10期290-304,共15页
In this work,we investigate disordered Dirac fermions from the perspective of quantum entanglement,which provides a different angle compared to the ordinary perturbative renormalization group(RG)analysis.We consider D... In this work,we investigate disordered Dirac fermions from the perspective of quantum entanglement,which provides a different angle compared to the ordinary perturbative renormalization group(RG)analysis.We consider Dirac fermions subjected to random hopping and random flux,which respectively fall into the chiral Gaussian orthogonal ensemble(cGOE)and chiral Gaussian unitary ensemble(cGUE)universality classes.Existing studies based on perturbative calculations suggest that both types of randomness are marginal.Here,through numerical simulations of the corresponding lattice models,we find that these two different types of randomness exhibit distinct entanglement features,signaling completely different properties in contrast to the perturbative RG analysis.In particular,although the entropy area-law is generally held for both types of randomness,we identify that the subleading term of the entanglement entropy is enhanced by random flux but not by random hopping.This subleading term is known as the entropic F-function in the clean limit without disorder.Our observations indicate that disordered theories in cGOE and cGUE are essentially different,which recalls careful analysis on the RG calculations. 展开更多
关键词 disordered dirac fermions quantum entanglementwhich ENTANGLEMENT perturbative calculations dirac fermions chiral gaussian orthogonal ensemble cgoe random hopping chiral gaussian unitary
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Deciphering the Lattice Vibrational Behaviors of CuInP2S6 by Angle-Resolved Polarized Raman Scattering
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作者 Yiqi Hu Junjie Zhang +12 位作者 Zhou Zhou Shun Wang Qiankun Li Yanfei Hou Tianhao Ying Lingling Yang Jingyao Zhang Shuzhong Yin Yuyan Weng Shuai Dong Jianlin Yao Liang Fang Lu You 《Chinese Physics Letters》 2025年第12期413-445,共33页
The layered van der Waals(vdW)ferroelectric CuInP2S6(CIPS)exhibits unique cation-hopping-driven phenomena that bring about unconventional properties with intriguing mechanisms and hold promise for advanced application... The layered van der Waals(vdW)ferroelectric CuInP2S6(CIPS)exhibits unique cation-hopping-driven phenomena that bring about unconventional properties with intriguing mechanisms and hold promise for advanced applications in nanoelectronics.However,an explicit analysis of its lattice dynamics and vibrational symmetries,pivotal for understanding the material’s peculiar ferroelectric and ferroionic behaviors,remains incomplete.Here,we employ angle-resolved polarized Raman spectroscopy in concert with first-principles calculations to systematically unravel the anisotropic lattice vibrations of CIPS single crystals.By analyzing the polarization-dependent Raman intensities,we determine the symmetry assignments and Raman tensors of all major vibrational modes,revealing good agreement with theoretical predictions.Furthermore,we demonstrate the utility of Raman spectroscopy as a sensitive and non-invasive probe for structural and ferroelectric order evolution by examining temperature-driven phase transitions and thickness-dependent polarization suppression in CIPS.Our findings establish a foundational framework for correlating lattice dynamics with functional properties in CIPS and provide a methodological blueprint for studying other vdW ferroelectrics. 展开更多
关键词 Raman spectroscopy CuInP S ferroelectric ferroionic behaviorsremains lattice dynamics cation hopping vibrational symmetries angle resolved polarized Raman scattering lattice dynamics vibrational symmetriespivotal
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HOP10V粉末冶金钢热变形行为研究
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作者 王世超 朱宝平 +3 位作者 王珍珍 孙莉洁 尚高锋 刘静 《模具制造》 2025年第12期171-173,共3页
为研究HOP10V粉末冶金高速钢的热变形行为规律,在变形温度为1 000~1 150℃、应变速率为0.1~10s^(-1)、变形量为30%的条件下对试样进行压缩变形实验,分析各变形条件下的显微组织,结果表明:HOP10V粉末冶金高钒钢是一种温度和应变速率敏感... 为研究HOP10V粉末冶金高速钢的热变形行为规律,在变形温度为1 000~1 150℃、应变速率为0.1~10s^(-1)、变形量为30%的条件下对试样进行压缩变形实验,分析各变形条件下的显微组织,结果表明:HOP10V粉末冶金高钒钢是一种温度和应变速率敏感材料,其峰值应力随着应变速率的降低和变形温度的升高而降低;材料的热变形激活能为474.297kJ/mol;热变形过程中,在较低应变速率条件下功率耗散因子值较大;当变形温度较低、应变速率较高时更易发生失稳,综合来看,HOP10V材料热加工的最优变形温度:T=1 060~1 150℃/0.1~10s^(-1)。 展开更多
关键词 HOP10V粉末冶金高速钢 本构方程 热加工图 显微组织
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基于双通信半径的传感器网络DV-Hop定位算法 被引量:45
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作者 李娟 刘禹 +1 位作者 钱志鸿 卢长刚 《吉林大学学报(工学版)》 EI CAS CSCD 北大核心 2014年第2期502-507,共6页
为了减少传统的DV—Hop算法对未知节点定位时产生的较大误差,分析了影响传统DV—Hop算法定位精度的两个因素,继而提出了一种改进算法。改进算法在进行未知节点定位时,信标节点先后使用两个通信半径广播自身位置信息,从而获得未知节... 为了减少传统的DV—Hop算法对未知节点定位时产生的较大误差,分析了影响传统DV—Hop算法定位精度的两个因素,继而提出了一种改进算法。改进算法在进行未知节点定位时,信标节点先后使用两个通信半径广播自身位置信息,从而获得未知节点与信标节点间更精确的跳数,并计算出它们之间更精确的距离,得到未知节点更精确的坐标。仿真结果显示,改进算法相比于传统DV—Hop算法相对定位误差减少了13%~15%,并且减少了由于网络拓扑结构不同带来的定位误差的差异性。 展开更多
关键词 通信技术 无线传感器网络 节点定位 DV—Hop算法 改进算法
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基于RSSI每跳分级和跳距修正的DV-HOP改进算法 被引量:33
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作者 张爱清 叶新荣 +1 位作者 胡海峰 丁绪星 《仪器仪表学报》 EI CAS CSCD 北大核心 2012年第11期2552-2559,共8页
针对DV-HOP(distance vector hop)算法的定位精度对节点间跳数信息依赖性较强的特点,提出一种基于接收信号强度指示(received signal strength indicator,RSSI)每跳分级和平均跳距修正的DV-HOP改进算法RADV-HOP(RSSI and average hoppin... 针对DV-HOP(distance vector hop)算法的定位精度对节点间跳数信息依赖性较强的特点,提出一种基于接收信号强度指示(received signal strength indicator,RSSI)每跳分级和平均跳距修正的DV-HOP改进算法RADV-HOP(RSSI and average hopping distance modifying DV-HOP)。仿真结果表明:在相同的网络环境里,与传统DV-HOP算法相比,RADV-HOP定位算法仅需节点通信芯片带有RSSI指示功能及增加少量的计算和通信开销,不需要额外的硬件开销,将每跳分为3个子级时,归一化定位误差能下降65%;与其他DV-HOP修正算法相比,RADV-HOP算法以相同的通信开销和稍微增加的计算开销使定位误差下降了45%。 展开更多
关键词 无线传感器网路 DV—HOP 接收信号强度指示 每跳分级
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一种基于加权处理的无线传感器网络平均跳距离估计算法 被引量:52
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作者 刘锋 张翰 杨骥 《电子与信息学报》 EI CSCD 北大核心 2008年第5期1222-1225,共4页
定位技术是无线传感器网络的关键技术之一,传统DV-Hop定位算法只考虑了最近一个锚节点估计的平均跳距离值,而单个锚节点估计的平均跳距离值无法准确地反映网络的实际平均跳距离。本文提出了一种基于加权处理的平均跳距离估计算法,考虑... 定位技术是无线传感器网络的关键技术之一,传统DV-Hop定位算法只考虑了最近一个锚节点估计的平均跳距离值,而单个锚节点估计的平均跳距离值无法准确地反映网络的实际平均跳距离。本文提出了一种基于加权处理的平均跳距离估计算法,考虑多个锚节点估计的平均跳距离值,根据距离未知节点的跳数进行加权,使网络平均跳距离的估计更加准确,从而提高定位精度。仿真结果表明,与DV-Hop算法的平均跳距离估计算法相比,本文算法更准确地估计平均跳距离,降低了均方根误差,并提高了定位精度。 展开更多
关键词 无线传感器网络 平均跳距离 定位 DV—Hop
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