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Filling up complex spectral regions through non-Hermitian disordered chains

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Chinese Physics B 2022年第5期31卷 1-9页

作者： Hui jiang Ching hua Lee Department of Physics National University of SingaporeSingapore 117551Republic of Singapore

Eigenspectra that fill regions in the complex plane have been intriguing to many,inspiring research from random matrix theory to esoteric semi-infinite bounded non-Hermitian *** this work,we propose a simple and robust ansatz for constructing models whose eigenspectra fill up generic prescribed *** approach utilizes specially designed non-Hermitian random couplings that allow the co-existence of eigenstates with a continuum of localization lengths,mathematically emulating the effects of semi-infinite *** some of these couplings are necessarily long-ranged,they are still far more local than what is possible with known random matrix *** ansatz can be feasibly implemented in physical platforms such as classical and quantum circuits,and harbors very high tolerance to imperfections due to its stochastic nature.

关键词： non-Hermitian skin effect disordered chain disorder localization non-Hermitian spectra

深刺八髎穴配合艾灸治疗脑卒中后急迫性尿失禁临床观察

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针灸临床杂志 2016年第12期32卷 53-56页

作者：靳晶刘江华姜磊刘麒麟邱厚道武汉市中医医院湖北武汉430014

目的：观察深刺八髎穴配合艾灸治疗脑卒中后急迫性尿失禁的临床疗效。方法：将60例脑卒中后急迫性尿失禁住院患者随机分为治疗组（35例）和对照组（25例）。治疗组给予电针刺八髎穴,采用连续波,频率强度50 Hz,持续20~30 min,每天1次,每... 详细信息

目的：观察深刺八髎穴配合艾灸治疗脑卒中后急迫性尿失禁的临床疗效。方法：将60例脑卒中后急迫性尿失禁住院患者随机分为治疗组（35例）和对照组（25例）。治疗组给予电针刺八髎穴,采用连续波,频率强度50 Hz,持续20~30 min,每天1次,每周5天,同时取关元、中极施以温和灸;对照组给予口服酒石酸托特罗定片,每次2 mg,每日2次。观察两组患者治疗前后48 H尿垫尿量占比、日排尿频率及尿失禁程度评定的变化。结果：两组患者治疗前后48 H尿垫尿量占比、日排尿频率及尿失禁程度评定均有显著性差异（P〈0.05）,且治疗组疗效明显优于对照组（P〈0.05）。结论：深刺八髎配合艾灸可以有效治疗脑卒中后急迫性尿失禁,提高患者的生活质量。

关键词：脑卒中急迫性尿失禁针灸疗法八髎电针

Development of a roof bolter drilling control process to reduce the generation of respirable dust

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International Journal of Coal Science & Technology 2021年第2期8卷 199-204页

作者： hua jiang Yi Luo Centers for Disease Control and Prevention National Institute for Occupational Safety and HealthPittsburghPAUSA Department of Mining Engineering West Virginia UniversityMorgantownWVUSA

The drilling operation in the roof bolting process,especially in hard rock,generates excessive respirable coal and quartz dusts,which could expose the roof bolting operator to continued health *** research has shown that the amount of respirable dust produced is dependent on the main drilling parameters,specifically the drilling rotational and penetration *** this paper,a roof bolter drilling control process was proposed to reduce the generation of respirable *** on the analysis of laboratory drilling test results,a rational drilling control process(adjusting rotational and penetration rates)to achieve the optimal drilling parameter for different rock types was *** this process,the ratio between specific energy and rock uniaxial compressive strength was used as the index to determine the optimal operation *** recommended drilling operation range for the rock type used in the experiment was provided,and the reduction in respirable dust generation was *** following this control process,the drilling efficiency can be monitored in real time,so the system can stay in a relatively high-energy efficiency with less respirable dust production from the drilling *** algorithm is targeted to be incorporated into the current roof bolter drilling control system for drilling automation so that a safe and productive drilling operation can be conducted in a healthy working environment.

关键词： Roof bolter Drilling control Respirable dust Specific energy

A new three-dimensional Hoek-Brown strength criterion

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Acta Mechanica Sinica 2012年第2期28卷 393-406页

作者： hua jiang Yong-Li Xie Key Laboratory for Bridgeand Tunnel of Shaanxi Province Chang'an University710064 Xi'anChina

The Hoek-Brown （HB） strength criterion has been widely applied to the estimation of strength of intact rock and rock mass, while evolving ever since. However, negligence of the effect of the intermediate principal stress still remains in the criterion＇s latest version. At the same time, several three-dimensional （3D） HB strength, which can takes into account the influence of the intermediate principal stress, have already been proposed, among which the 3D HB criterion proposed by Zhang and Zhu seems to be the most reasonable one. However, the Zhang 3D HB criterion may have problems with some stress path close to triaxial extension state because of the non-convexity characteristic of its failure surface. In this paper, a new 3D HB strength criterion is presented based on a generalized form of the HB criterion, which also considers the effect of the intermediate principal stress and inherits all the merits of the original version of the HB criterion. In addition, this new criterion can remedy to some extent the shortcomings observed in the Zhang 3D HB criterion. Polyaxial tests for five different rocks from pub- lished literatures are used for evaluating this new criterion and comparing it with the Zhang 3D HB criterion. The re- sults show that this new criterion may over-predict or under- predict the polyaxial strength of rocks but the errors are rela- tively small, and similar results are also found for the Zhang 3D HB criterion, which one is better depends on the type of the rock under estimation.

关键词： Hoek-Brown criterion Rock strength Merid-ian plane Octahedral plane

Comparative Study of the Rock-breaking Mechanism of a Disc Cutter and Wedge Tooth Cutter by Discrete Element Modelling

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Chinese Journal of Mechanical Engineering 2023年第3期36卷 269-285页

作者： hua jiang Huiyan Zhao Xiaoyan Zhang Yusheng jiang Yaofu Zheng School of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing 100083China Beijing Urban Construction Group Co. Ltd.Beijing 100088China

The operation of a shield tunnel boring machine(TBM)in a high-strength hard rock stratum results in significant cutter damage,adversely affecting the thrust and torque of the cutter ***,it is very important to carry out the research on the stress characteristics and optimize the cutter parameters of cutters break high-strength hard *** this paper,the rock-breaking performance of cutters in an andesite stratum in the tunnel of Qingdao Metro Line No.8 was investigated using the discrete element method and theoretical *** rock-breaking processes of a disc cutter and wedge tooth cutter were simulated by software particle flow code PFC^(3D),and the rock-breaking degree,stress of the cutter,and rock-breaking specific energy were *** rock damage caused by the cutter in a specific section was divided into three stages:the advanced influence,crushing,and stabilizing *** rock-breaking degree and the tangential and normal forces of the wedge tooth cutter are larger than that of the disc cutter under the same *** disc cutter(wedge tooth cutter)has the highest rock-breaking efficiency at a cutter spacing of 100 mm(110 mm)and a penetration depth of 8 mm(10 mm),and the rock-breaking specific energy is 11.48 MJ/m^(3)(12.05 MJ/m^(3)).Therefore,two types of cutters with different penetration depths or cutter spacing should be *** number of teeth of wedge tooth cutters can be increased in hard strata to improve the rock-breaking efficiency of the *** research results provide a reference for shield cutterhead selection and cutter layout in similar projects.

关键词： Qingdao andesite Rock breaking with cutter Wedge tooth cutter Specific energy PFC^(3D)

A New Solution to Intrusion Detection Systems Based on Improved Federated-Learning Chain

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Computers, Materials & Continua 2024年第6期79卷 4491-4512页

作者： Chunhui Li hua jiang School of Computer and Electronic Information Guangxi UniversityNanning530000China Cyber Security and Information Center Guangxi UniversityNanning530000China

In the context of enterprise systems,intrusion detection(ID)emerges as a critical element driving the digital transformation of *** systems spanning various sectors of enterprises geographically dispersed,the necessity for seamless information exchange has surged *** existing cross-domain solutions are challenged by such issues as insufficient security,high communication overhead,and a lack of effective update mechanisms,rendering them less feasible for prolonged application on resource-limited *** study proposes a new cross-domain collaboration scheme based on federated chains to streamline the server-side *** this framework,individual nodes solely engage in training local data and subsequently amalgamate the final model employing a federated learning algorithm to uphold enterprise systems with efficiency and *** curtail the resource utilization of blockchains and deter malicious nodes,a node administration module predicated on the workload paradigm is introduced,enabling the release of surplus resources in response to variations in a node’s contribution *** encountering an intrusion,the system triggers an alert and logs the characteristics of the breach,facilitating a comprehensive global update across all nodes for collective *** results across multiple scenarios have verified the security and effectiveness of the proposed solution,with no loss of its recognition accuracy.

关键词： Cross-domain collaboration blockchain federated learning contribution value node management release slack resources

Stability of second-order stochastic neutral partial functional differential equations driven by impulsive noises

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Science China(Information Sciences) 2016年第11期59卷 117-127页

作者： Feng jiang hua YANG Yi SHEN School of Statistics and Mathematics Zhongnan University of Economics and Law School of Automation Huazhong University of Science and Technology School of Mathematics and Computer Science Wuhan Polytechnic University

This paper investigates the stability of second-order stochastic neutral partial functional differential equations driven by impulsive noises. Some sufficient conditions ensuring pth moment exponential stability of the second-order stochastic neutral partial functional differential equations driven by impulsive noises are obtained by establishing a new impulsive-integral inequality. These existing results are generalized and improved by the present study. Finally, an example is given to show the effectiveness of our results.

关键词： second-order stochastic neutral partial functional differential equations exponential stability impulsive noises sine family cosine family

A three-dimensional numerical study on instability of sinusoidal flame induced by multiple shock waves

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Acta Mechanica Sinica 2017年第2期33卷 316-326页

作者： Xiao Chen Gang Dong hua jiang Key Laboratory of Transient Physics Nanjing University of Science and Technology Nanjing 210094 China

The instabilities of a three-dimensional sinusoidally premixed flame induced by an incident shock wave with Mach = 1.7 and its reshock waves were studied by using the Navier-Stokes (NS) equations with a single-step chemical reaction and a high resolution, 9th-order weighted essentially non-oscillatory scheme. The computational results were validated by the grid independence test and the experimental results in the literature. The computational results show that after the passage of incident shock wave the flame interface develops in symmetric structure accompanied by large-scale transverse vortex structures. After the interactions by successive reshock waves, the flame interface is gradually destabilized and broken up, and the large-scale vortex structures are gradually transformed into small-scale vortex structures. The small-scale vortices tend to be isotropic later. The results also reveal that the evolution of the flame interface is affected by both mixing process and chemical reaction. In order to identify the relationship between the mixing and the chemical reaction, a dimensionless parameter, , that is defined as the ratio of mixing time scale to chemical reaction time scale, is introduced. It is found that at each interaction stage the effect of chemical reaction is enhanced with time. The enhanced effect of chemical reaction at the interaction stage by incident shock wave is greater than that at the interaction stages by reshock waves. The result suggests that the parameter can reasonably character the features of flame interface development induced by the multiple shock waves.

关键词： Shock wave Flame interface RM instability Chemical reaction Vortex structure

Preparation and characterization of barium strontium titanate/silicon nanoporous pillar array composite thin films by a sol-gel method

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International Journal of Minerals,Metallurgy and Materials 2012年第8期19卷 762-767页

作者： Shun-hua Xiao Wei-fen jiang Co11ege of Chemistry and Bioengineering Key Laboratory of New Processing Technology for Nonferrous Metals and Materials (Ministry of Education) Guilin University of Technology Guilin 541004 China Department of Mathematics and Information Science North China Institute of Water Conservancy and Hydroelectric Power Zhengzhou 450011 China

Barium strontium titanate （Ba0.5Sr0.5TiO3, BST）/silicon nanoporous pillar array （Si-NPA） thin films were prepared by a spin-coating/annealing technique based on Si-NPA with micro/nano-structure. Both the isomer conversion of acetylacetone and the network structure combined by enol and Ti-alkoxide facilitate the formation of the BST sol and the subsequent crystallization. Before the perovskite BST begins to form, the intermediate phase （Ba, Sr）Ti2OsCO3 is found. The boundary between BST and Si-NPA is of clarity and little interface diffusion, disclosing that Si-NPA is an ideal template substrate in the preparation of multifunctional composite films.

关键词： barium strontium titanate silicon nanoporous materials composite films sol-gel process