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Science China(Information Sciences) 2016年第1期59卷 80-94页

作者： hongyi chen Zhigang SUN Fei YI Jinshu SU School of Computer National University of Defense Technology

Large-scale streaming media distribution services impart unprecedented pressures and challenges to existing Internet architecture. Researchers have proposed CDN, P2 P Cache, ICN and other solutions to alleviate the pressure of the core network, as well as improve the user experience(Qo E). All these solutions achieve their goals by deploying storage resources close to the end users to cache the hot data. Based on the advantages of P2 P service, which takes into account end-users resources, we proposed the Buffer Bank Storage(BBS). It is a new streaming media distribution-oriented storage model by aggregating end-users resources. This provides a novel approach for implementation of economic, scalable, dynamically deploy streaming media distribution applications. However, the dynamic character of the end-user behavior brings challenges to BBS designation. In our previous work, we have analyzed the basic principle of BBS and its feasibility. There is lack of substantial research on resources management and reliability assessment, which are the core issue of BBS *** carefully analyzing the reliability and security issue in BBS deployment, this paper has proposed the implementation model of BBS and studied the performance of different buffer allocation mechanism through simulation. Our work mainly provides a new way of thinking for the dynamic, universal scalable storage system in the Internet, that suffers "weak reliability".

关键词： in-network storage P2P Cache streaming media distributed resources management

Machine Learning in Predicting Printable Biomaterial Formulations for Direct Ink Writing

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Research 2023年第4期2023卷 105-115页

作者： hongyi chen Yuanchang Liu Stavroula Balabani Ryuji Hirayama Jie Huang Department of Mechanical Engineering University College LondonLondonUK Department of Computer Science University College LondonLondonUK Wellcome-EPSRC Centre for Interventional Surgical Sciences(WEISS) University College LondonLondonUK.

Three-dimensional(3D)printing is emerging as a transformative technology for biomedical *** 3D printed product can be patient-specific by allowing customizability and direct control of the *** trial-and-error approach currently used for developing the composition of printable inks is time-and resource-consuming due to the increasing number of variables requiring expert *** intelligence has the potential to reshape the ink development process by forming a predictive model for printability from experimental *** this paper,we constructed machine learning(ML)algorithms including decision tree,random forest(RF),and deep learning(DL)to predict the printability of biomaterials.A total of 210 formulations including 16 different bioactive and smart materials and 4 solvents were 3D printed,and their printability was *** ML methods were able to learn and predict the printability of a variety of inks based on their biomaterial *** particular,the RF algorithm has achieved the highest accuracy(88.1%),precision(90.6%),and F1 score(87.0%),indicating the best overall performance out of the 3 algorithms,while DL has the highest recall(87.3%).Furthermore,the ML algorithms have predicted the printability window of biomaterials to guide the ink *** printability map generated with DL has finer granularity than other *** has proven to be an effective and novel strategy for developing biomaterial formulations with desired 3D printability for biomedical engineering applications.

关键词： printing formulation biomaterials

Geological characteristics of the Sizhuang gold deposit in the region of Jiaodong, Shandong Province——A study on tectono-geochemical ore prospecting of ore deposits

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Chinese Journal Of Geochemistry 2011年第4期30卷 539-553页

作者： QIAN Jianping chen hongyi MENG Yong College of Earth Sciences Guilin University of Technology Guangxi Guilin 541004 China

Tectono-geochemical samples were systematically collected from 5 drillcores along the No. 304 explora-tion line and at the -310 m level under the pit in the mining area, totalling 705 samples from the metamorphic rocks, granites, altered rocks and orebodies, and were determined for their contents of 20 kinds of elements including Au, Ag, As, Sb, Hg, Cu,,Pb, Zn, Sn, Bi, Mo, Co, Ni, Mn, Cr, V, Ti, Ba, Rb, Sr, etc. By using the Surfer software the geochemical exploration line profile maps for the 20 kinds of elements and the curves for the element geochemical contents of individual ore vein groups were established. In conbination with the geochemical map analytical method and Gregorian's zoning index calculation method, the vertical, longitudinal and lateral zonation sequences of the elements were ascertained and the geochemical three-dimentional zonation model of the primary halos was estab-lished on the basis of the analysis of metallogenic structures and alteration zonation. Coupled with the results of analysis of the geology and geochemistry data, it may be concluded that the process of alteration of granites in the mining area is also accompanied with the process of gold enrichment and mineralization. With the intensification of alteration of granites from granite →potash feldspathization granite →sericite-quartz alteration granite, seric-ite-quartz rocks →beresitized granite, pyrite sericite-quartz rock, silicified granite →gold ore, the contents of thio-phile ore-forming elements such as Au, Ag, As, Cu, Bi, Mo, Pb, Sb, Hg, and Sn tended to increase. Factor analysis of trace elements indicated: factor F2 (Au, Ag, Cu, Sn, As) represents the element association brought in at the main stage of hydrothermal metallogenesis; factor F4 (Bi, Sb) and factor F5 (Pb, Zn) represent the ore-forming element association supperposed during the late stage of Au-bearing sulfides. By using the Gregorian's zoning index and map analysis method we have ascertained the primary halo axi

关键词：构造地球化学金矿床金矿石地质特征矿床勘探胶东地区元素地球化学矿化蚀变分带

Hollow sphere of heterojunction(NiCu)S/NC as advanced anode for sodium-ion battery

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Journal of Energy Chemistry 2023年第7期82卷 248-258,I0006页

作者： hongyi chen Pengfei Lv Pengfu Tian Shiyue Cao Shengjun Yuan Qiming Liu Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan 430072HubeiChina

Metal sulfide is considered as a potential anode for sodium-ion batteries(SIBs),due to the high theoretical capacity,strong thermodynamic stability and ***,their cycle capacity and rate performance are limited by the excessive expansion rate and low intrinsic ***,heterogeneous hollow sphere NiS-Cu_(9)S_(5)/NC(labeled as(NiCu)S/NC)based on Oswald ripening mechanism was prepared through a simple and feasible *** a structural perspective,the hollow structure provides an expansion buffer and raises the electrochemical active *** terms of electron/ion during the cycles,Na^(+)storage mechanism is optimized by NiS/Cu_(9)S_(5)heterogeneous interface,which increases the storage sites and shortens the migration path of Na^(+).The formation of built-in electric field strengthens the electron/ion *** on the first principle calculations,it is further proved the formation of heterogeneous interfaces and the direction of electron *** the anode for SIBs,the synthesized(NiCu)S/NC delivers high reverse capacity(559.2 mA h g^(-1)at 0.5 A g^(-1)),outstanding rate performance(185.3 mA h g^(-1)at 15 A g^(-1)),long-durable stability(342.6 mA h g^(-1)at 4 A g^(-1)after 1500cycles,150.0 m A h g^(-1)at 10 A g^(-1)after 20,000 cycles with 0.0025%average attenuation rate).The matching cathode electrode Na_(3)V_(2)(PO_(4))_(3)/C is assembled with(NiCu)S/NC for the full-battery that achieves high energy density(253.7 W h kg^(-1))and reverse capacity(288.7 mA h g^(-1)).The present work provides a distinctive strategy for constructing electrodes with excellent capacity and stability for SIBs.

关键词： Hollow structure Heterogeneous interface First principle calculations Sodium-ion batteries

AC loss mitigation for high temperature superconducting coils in wireless power transfer

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Superconductivity 2023年第2期6卷 6-24页

作者： hongyi chen Hongye Zhang Research Center for Graph Computing Zhejiang LabHangzhouChina Department of Electrical and Electronic Engineering University of ManchesterManchester M139PLUnited Kingdom

With the rapid development of high temperature superconducting(HTS)technology,second generation(2G)HTS materials have become a promising alternative to traditional conductive materials in the power transmission ***,the topic of using HTS materials in wireless power transfer(WPT)systems for electric vehicles(EVs)has attracted widespread attention in the background of net zero *** virtually zero DC resistance and superior current‐carrying capacity,HTS materials can achieve high quality factor and power density in the WPT resonant circuits compared to conventional metals,e.g.,***,the optimal working frequency for the conventional WPT system is relatively high in the order of kilohertz *** coils working at high frequencies could generate high AC losses,reducing the overall power transfer efficiency(PTE)and increasing the cooling *** order to improve the PTE of HTS‐WPT systems,the AC loss mitigation methods for different HTS coil topologies have been investigated in this paper by varying the inter‐turn gap and tape *** HTS coil structures,namely the spiral coil,the solenoid coil and the double pancake(DP)coil,have been studied with a 2D axisymmetric multi‐layer numerical model based on the H‐formulation,and the simulation results have been validated by the published experimental *** general loss characteristics,loss distributions in each turn,as well as magnetic flux densities have been analysed in detail for three types of HTS ***,the impact of these two loss reduction methods on the WPT performance has also been *** have shown that increasing the inter‐turn gap and tape width can effectively reduce the AC power losses and increase the PTE of the HTS‐WPT *** spiral coil demonstrates the highest AC power loss reduction effect and PTE while maintaining a stable level of magnetic *** paper is believed to deepen the understanding of superconducting WPT and provi

关键词： Wireless Power Transfer(WPT) High temperature superconductor Loss reduction Inter‐turn gap Tape width

Key Recovery Against 3DES in CPU Smart Card Based on Improved Correlation Power Analysis

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Tsinghua Science and Technology 2016年第2期21卷 210-220页

作者： Yanting Ren Liji Wu Hexin Li Xiangyu Li Xiangmin Zhang An Wang hongyi chen Tsinghua National Laboratory for Information Science and Technology(TNList)and the Institute of Microelectronics Tsinghua UniversityBeijing 100084China China Information Technology Security Evaluation Center(CNITSEC) Beijing 100085China School of Computer Science&Technology Beijing Institute of TechnologyBeijing 100081China

The security of CPU smart cards, which are widely used throughout China, is currently being threatened by side-channel analysis. Typical countermeasures to side-channel analysis involve adding noise and filtering the power consumption signal. In this paper, we integrate appropriate preprocessing methods with an improved attack strategy to generate a key recovery solution to the shortcomings of these countermeasures. Our proposed attack strategy improves the attack result by combining information leaked from two adjacent clock cycles. Using our laboratory-based power analysis system, we verified the proposed key recovery solution by performing a successful correlation power analysis on a Triple Data Encryption Standard （3DES） hardware module in a real-life 32-bit CPU smart card. All 112 key bits of the 3DES were recovered with about 80 000 power traces.

关键词： Triple Data Encryption Standard (3DES) CPU smart cards power analysis key recovery side-channeanalysis

Field Quantization and Spontaneous Emission in Left-handed Material

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量子光学学报 2006年第B08期12卷 77-78页

作者： hongyi chen Chunguang Du Shiqun Li Key Laboratory for Quantum Information and Measurements of Education Ministry Department of Physics TsinghuaUniversity Belling 100084 P. R. China.

Theoretical Research on a Kind of Quantum Left-handed Metamaterial

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量子光学学报 2006年第B08期12卷 70-71页

作者： Chunguang Du hongyi chen Shiqun Li Key Laboratory for Quantum Information and Measurements of Education Ministry Department of Physics Tsinghua University Beijing 100084 P. R. China

Enhanced Thermoelectric Properties of Cu_(x)Se(1.75 ≤ x ≤ 2.10) during Phase Transitions

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Chinese Physics Letters 2021年第11期38卷 59-66页

作者： Zhongmou Yue Kunpeng Zhao hongyi chen Pengfei Qiu Lidong chen Xun Shi State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China

Coupling of a phase transition to electron and phonon transports provides extra degree of freedom to improve the thermoelectric performance, while the pertinent experimental and theoretical studies are still rare. Particularly,the impaction of chemical compositions and phase transition characters on the abnormal thermoelectric properties across phase transitions are largely unclear. Herein, by varying the Cu content x from 1.75 to 2.10, we systemically investigate the crystal structural evolution, phase transition features, and especially the thermoelectric properties during the phase transition for Cu_(x)Se. It is found that the addition of over-stoichiometry Cu in Cu_(x)Se could alter the phase transition characters and suppress the formation of Cu vacancies. The critical scatterings of phonons and electrons during phase transitions strongly enhance the Seebeck coefficient and diminish the thermal conductivity, leading to an ultrahigh dimensionless thermoelectric figure of merit of ~1.38 at 397 K in Cu_(2.10)*** the decreasing Cu content, the critical electron and phonon scattering behaviors are mitigated, and the corresponding thermoelectric performances are reduced. This work offers inspirations for understanding and tuning the thermoelectric transport properties during phase transitions.

关键词： red during Phase Transitions Enhanced Thermoelectric Properties of Cu_(x)Se

Mitigating the Jahn-Teller distortion driven by the spin-orbit coupling of lithium manganate cathode

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Journal of Energy Chemistry 2022年第9期31卷 379-387,I0011页

作者： Shu Zhang hongyi chen Jun chen Shouyi Yin Yu Mei Lianshan Ni Andi Di Wentao Deng Guoqiang Zou Hongshuai Hou Xiaobo Ji State Key Laboratory of Powder Metallurgy College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083HunanChina Department of Materials and Environmental Chemistry Stockholm UniversityStockholm 10691Sweden

Spinel LiMn_(2)O_(4)is recognized as one of the most competitive cathode candidates for lithium-ion batteries ascribed to environmentally benign and rich ***,the wholesale application of LiMn_(2)O_(4)is predominately plagued by its severe capacity degradation,mainly associated with the innate Jahn-Teller ***,single-crystalline LiMn_(2)O_(4)with Eu^(3+) doping is rationally designed to mitigate the detrimental Jahn-Teller distortion by tuning the chemical environment of MnO_(6) octahedra and accommodating localized electron,based on the unique aspheric flexible 4f electron orbit of rare-earth metal ***,the stretching of MnO_(6) octahedron stemmed from the Jahn-Teller effect in Eu-doped LiMn_(2)O_(4)is effectively suppressed,confirmed by theoretical ***,the structural stability of the material has been significantly enhanced due to the robust Mn–O band coherency and weakened phase transition,proved by synchrotron radiation absorption spectrum and operando X-ray *** corresponding active cathode manifests superior long-cycle stability after 300 loops at 2C and displays only a 0.011%capacity drop per cycle even at *** this,this modification tactic sheds new light on achieving superior long-cycle performances by suppressing distortion in various cathode materials.

关键词： Spinel lithium manganate Spin-orbit coupling Jahn-Teller distortion Cathode material