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Defence Technology（防务技术） 2022年第6期18卷 1065-1072页

作者： Xing-yu Wu ming-yu Li qing-xuan Zeng qing-xia Yu State Key Laboratory of Explosion and Technology Beijing Institute of TechnologyBeijing100081PR China

Copper azide with high density was successfully synthesized by in-situ reaction of nanoporous copper(NPC)precursor with HN_(3) *** with pore size of about 529 nm has been prepared by electroless plating using polystyrene(PS)as *** copper shells thickness of NPC was controlled by adjusting the PS loading *** effects of copper shell on the morphology,structure and density of copper azide were *** conversion increased from 87.12%to 95.31%when copper shell thickness decrease from 100 to 50 ***,the density of copper azide prepared by 529 nm NPC for 24 h was up to 2.38 g/cm^(3).The hollow structure of this NPC was filled by swelling of copper azide which guaranteed enough filling volume for keeping the same shape as well as improving the charge ***,HNS-IV explosive was successfully initiated by copper azide with minimum charge thickness of 0.55 mm,showing that copper azide prepared has excellent initiation performance,which has more advantages in the application of miniaturized explosive systems.

关键词： Nanoporous copper Electroless plating In-situ reaction Copper azide

On the rate of convergence for multi-category classification based on convex losses

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Science China Mathematics 2007年第11期50卷 1529-1536页

作者： Hong CHEN luo-qing LI Faculty of Mathematics and Computer Science Hubei UniversityWuhan 430062China Faculty of Mathematics and Computer ScienceHubei UniversityWuhan 430062China

The multi-category classification algorithms play an important role in both theory and practice of machine *** this paper,we consider an approach to the multi-category classification based on minimizing a convex surrogate of the nonstandard misclassification *** bound the excess misclassification error by the excess convex *** construct an adaptive procedure to search the classifier and furthermore obtain its convergence rate to the Bayes rule.

关键词： misclassiflcation error consistency convergence rate

Analysis of security protocols based on challenge-response

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Science in China(Series F) 2007年第2期50卷 137-153页

作者： luo JunZhou YANG ming School of Computer Science and Engineering Southeast University Nanjing 210096 China

Security protocol is specified as the procedure of challenge-response, which uses applied cryptography to confirm the existence of other principals and fulfill some data negotiation such as session keys. Most of the existing analysis methods, which either adopt theorem proving techniques such as state exploration or logic reasoning techniques such as authentication logic, face the conflicts between analysis power and operability. To solve the problem, a new efficient method is proposed that provides SSM semantics-based definition of secrecy and authentication goals and applies authentication logic as fundamental analysis techniques, in which secrecy analysis is split into two parts： Explicit-lnformaUon-Leakage and Implicit-Information-Leakage, and correspondence analysis is concluded as the analysis of the existence relationship of Strands and the agreement of Strand pa- rameters. This new method owns both the power of the Strand Space Model and concision of authentication logic.

关键词： network security protocol analysis challenge-response Strand Space Model

Quark jet versus gluon jet: fully-connected neural networks with high-level features

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Science China(Physics,Mechanics & Astronomy) 2019年第9期62卷 49-59页

作者： Hui luo ming-Xing luo Kai Wang Tao Xu GuoHuai Zhu Graduate School of China Academy of Engineering Physics Beijing 100193China Zhejiang Institute of Modem Physics and Department of Physics Zhejiang UniversityHangzhou 310027China Institut fiir Theoretische Physik Universitat Hamburg Luruper Chaussee 149Hamburg D- 22761Germany

Jet identification is one of the fields in high energy physics that machine learning has begun to make an impact. More often than not, convolutional neural networks are used to classify jet images with the benefit that essentially no physics input is *** by a recent work by Datta and Larkoski, we study the classification of quark/gluon-initiated jets based on fully-connected neural networks(FNNs), where expert-designed physical variables are taken as input. FNNs are applied in two ways: trained separately on various narrow jet transverse momentum pTJbins;trained on a wide region of pTJ∈[200, 1000] GeV. We find their performances are almost the same. The performance is better when the pTJis larger. Jet discrimination with FNN is studied on both particle and detector level data. The results based on particle level data are comparable with those from deep convolutional neural networks, while the significance improvement characteristic(SIC) from detector level data would at most decrease by 15%.We also test the performance of FNNs with the full set or subsets of jet observables as input features. The FNN with one subset consisting of fourteen observables shows nearly no degradation of performance. This indicates that these fourteen expert-designed observables could have captured the most necessary information for separating quark and gluon jets.

关键词： standard model simulation quark-gluon jets machine learning

Metal-Free C_(3)N_(4) with plentiful nitrogen vacancy and increased specific surface area for electrocatalytic nitrogen reduction

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Journal of Energy Chemistry 2021年第9期30卷 546-555页

作者： Ziming Zhao Yu Long Sha luo Yutong luo ming Chen Jiantai Ma State Key Laboratory of Applied Organic Chemistry(SKLAOC) College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000GansuChina

As a substitute for synthetic ammonia under mild condition, electrocatalytic nitrogen reduction reaction(NRR) provides a hopeful approach for the development of ammonia. Nevertheless, the current development of NRR electrocatalysts is far from enough and a systematic research is needed to gain a better improvement. This article presents that 2 D C_(3)N_(4)-NV with a large specific surface area and abundant nitrogen vacancies is prepared by a simple and feasible method, and used as a metal-free catalyst for electrocatalytic NRR. Experiment result and density functional theory(DFT) calculation reveal that nitrogen vacancies in 2 D C_(3)N_(4)-NV can act as an efficient active site for catalytic NRR, which is conducive to capturing and activating N_(2), lowering Gibbs free energy(DG) in reaction and inhibiting hydrogen evolution reaction(HER) at the same time. In addition, the larger specific surface area also makes more active site exposed, which is good for the contact between the electrolyte and the active site, thus enhancing its NRR activity. The electrocatalyst shows an excellent catalytic activity for NRR in 0.1 M HCl, including Faradaic efficiency of 10.96%, NH_(3) yields of 17.85 lg h^(-1) mg_(cat)^(-1)., and good stability(over 20 h).

关键词： 2D C_(3)N_(4)-NV Larger specific surface area Nitrogen vacancy Electrocatalyst NRR

A New Chemical Trick to Prevent House from Collapsing by Bacterial Pathogens

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Chemical Research in Chinese Universities 2022年第2期38卷 478-480页

作者： QIU Jiazhang luo Zhao-qing State Key Laboratory for Zoonotic Diseases College of Veterinary MedicineJilin UniversityChangchun 130061P.R.China Purdue Institute for Inflammation Immunology and Infectious Disease and Department of Biological SciencesPurdue UniversityWest LafayetteINUSA

Metazoans often induce cell death as an ultimate strategy to prevent disastrous damage to the body under circumstances when insults,such as infection are impossible to *** cell death or pyroptosis not only eliminates the replicative niche for the pathogen but also stimulates effective immune protection.A recent study by Shao,Liu and colleagues found that the Shigella flexneri effector OspC3 inactivates an inflammasome by a novel posttranslational modification termed *** finding has greatly expanded the chemical tool box of pathogens in their manipulation of host function,which may be used to probe unrecognized signaling mechanisms.

关键词： death manipulation eliminate

Reactivity study and kinetic evaluation of CuO-based oxygen carriers modified by three different ores in chemical looping with oxygen uncoupling(CLOU)process

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Chinese Journal of Chemical Engineering 2021年第9期34卷 54-63页

作者： Cao Kuang Shuzhong Wang ming luo Jun Zhao Key Laboratory of Thermo-Fluid Science and Engineering of MOE School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013China

In the chemical looping with oxygen uncoupling(CLOU)process,CuO is a promising material due to the high oxygen carrier capacity and exothermic reaction in fuel reactor but limited by the low melting *** combustion rate of carbon is faster than the decoupling rate of oxygen carrier(OC).Hence,high temperature tolerance and rapid oxygen release rate of CuO modified by three different ores were investigated in this *** kinetics analysis of oxygen decoupling with Cu-based oxygen carriers was also *** showed that CuO modified by chrysolite had faster oxygen release rate than that of *** showed obvious positive effect on the oxidization *** selected OCs could keep stable in at least 20 cycles,for about 1200 *** core model(SCM)fitted well for the decoupling process in the temperature range of 1123-1223 *** rate kinetic information may aid in the development of chemical looping with oxygen uncoupling(CLOU)technologies during reactor design and process *** doped copper oxide with chrysolite and limestone could improve the reactivity of CuO in decoupling and coupling process and also improve the high temperature tolerance.

关键词： Reaction kinetics Chemical looping with oxygen uncoupling(CLOU) Sintering Natural ore CO_(2)capture

Applicability and comparison of solar-air source heat pump systems between cold and warm regions of plateau by transient simulation and experiment

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Building Simulation 2021年第6期14卷 1697-1708页

作者： luonan Xu ming Li Ying Zhang Xi luo Solar Energy Research Institute Yunnan Normal UniversityNo.768Juxian StreetChenggong districtKunmingYunnan 650500China

Solar-air source heat pump(solar-ASHP)system has a potential application in the field of hot water and space heating in residential *** system features the complementary advantages to solve the discontinuous operation of the single solar system and the frosting issue of the single ASHP *** paper built the solar-ASHP systems in Kunming and Shangri-La,and tested the system performance under different weather conditions in these two regions of ***,the transient heat balance models of the system were established under the sunlight time and non-sunlight time and were verified by the experimental ***,the verified model was applied to reveal the energy balance performance between the energy supply and building heat *** law of the system performance affected by the ambient temperature,effective heat collecting area,and cumulative heating capacity of collector was explored by the validated *** results indicate that when the ambient temperature decreases by 1℃during non-sunlight time,the energy efficiency ratio decreases by about 0.07.A square meter decline in the effective heat collecting area pushes an increase in the heating capacity of 5.75 ***,the cumulative heating capacity of collector increases by 5 MJ,and the ASHP energy consumption decreases by 0.54 *** dynamic changes of the ambient temperature and instantaneous solar radiation are the main reasons of the heat balance ***,both the developed system and model are feasible and reliable in different climate regions.

关键词： solar-ASHP system transient heat balance model model verification heat balance relationship different regions experimental analysis

BGNN: Behavior-aware graph neural network for heterogeneous session-based recommendation

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Frontiers of Computer Science 2023年第5期17卷 103-118页

作者： Jinwei luo mingkai HE Weike PAN Zhong ming College of Computer Science and Software Engineering Shenzhen UniversityShenzhen 518060China National Engineering Laboratory for Big Data System Computing Technology Shenzhen UniversityShenzhen 518060China

Session-based recommendation(SBR)and multibehavior recommendation(MBR)are both important problems and have attracted the attention of many researchers and *** from SBR that solely uses one single type of behavior sequences and MBR that neglects sequential dynamics,heterogeneous SBR(HSBR)that exploits different types of behavioral information(e.g.,examinations like clicks or browses,purchases,adds-to-carts and adds-to-favorites)in sequences is more consistent with real-world recommendation scenarios,but it is rarely *** efforts towards HSBR focus on distinguishing different types of behaviors or exploiting homogeneous behavior transitions in a sequence with the same type of ***,all the existing solutions for HSBR do not exploit the rich heterogeneous behavior transitions in an explicit way and thus may fail to capture the semantic relations between different types of ***,all the existing solutions for HSBR do not model the rich heterogeneous behavior transitions in the form of graphs and thus may fail to capture the semantic relations between different types of *** limitation hinders the development of HSBR and results in unsatisfactory *** a response,we propose a novel behavior-aware graph neural network(BGNN)for *** BGNN adopts a dual-channel learning strategy for differentiated modeling of two different types of behavior sequences in a ***,our BGNN integrates the information of both homogeneous behavior transitions and heterogeneous behavior transitions in a unified *** then conduct extensive empirical studies on three real-world datasets,and find that our BGNN outperforms the best baseline by 21.87%,18.49%,and 37.16%on average correspondingly.A series of further experiments and visualization studies demonstrate the rationality and effectiveness of our *** exploratory study on extending our BGNN to handle more than two types of behaviors show that our BGNN can e

关键词： session-based recommendation graph neural network heterogeneous behaviors

Beam emittance investigation in high brightness injector using different driver laser profiles

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 189-192页

作者： WANG XiaoHui SUN BaoGen luo qing School of Nuclear Science and Technology&National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

Beam emittance plays an important role in any accelerator, and it is a main parameter to judge the performance of an accelerator. Emittance optimization is an indispensable part in conditioning and operation of the facility. For a laser-driven high brightness injector, different time structure of the laser pulse has different effects on transverse emittance. In order to compare Gaussian and flat-top laser pulse, systematic simulations of 500 pC have been done. From the simulation results, one can see that flat-top pulse laser will yield smaller minimal transverse beam size and transverse beam emittance than Gaussian pulse laser.

关键词： transverse emittance laser pulse Gaussian flat-top phase space