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Three-dimensional stress variation characteristics in deep hard rock of CJPL-Ⅱ project based on in-situ monitoring

International Journal of Mining Science and Technology 2024年第2期34卷 179-195页

作者： Minzong zheng Shaojun Li Zejie Feng Huaisheng xu Yaxun Xiao State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

In deep hard rock excavation, stress plays a pivotal role in inducing stress-controlled failure. While the impact of excavation-induced stress disturbance on rock failure and tunnel stability has undergone comprehensive examination through laboratory tests and numerical simulations, its validation through insitu stress tests remains unexplored. This study analyzes the three-dimensional stress changes in the surrounding rock at various depths, monitored during the excavation of B2 Lab in China jinping Underground Laboratory Phase Ⅱ(CJPL-Ⅱ). The investigation delves into the three-dimensional stress variation characteristics in deep hard rock, encompassing stress components and principal stress. The results indicate changes in both the magnitude and direction of the principal stress during tunnel excavation. To quantitatively describe the degree of stress disturbance, a series of stress evaluation indexes are established based on the distances between stress tensors, including the stress disturbance index(SDI), the principal stress magnitude disturbance index(SDIm), and the principal stress direction disturbance index(SDId). The SDI indicates the greatest stress disturbance in the surrounding rock is 4.5 m from the tunnel wall in B2 Lab. SDIm shows that the principal stress magnitude disturbance peaks at2.5 m from the tunnel wall. SDId reveals that the largest change in principal stress direction does not necessarily occur near the tunnel wall but at a specific depth from it. The established relationship between SDI and the depth of the excavation damaged zone(EDZ) can serve as a criterion for determining the depth of the EDZ in deep hard rock engineering. Additionally, it provides a reference for future construction and support considerations.

关键词： Disturbance stress Tensor distance Stress disturbance index Principal stress direction Underground research laboratory

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Massively parallel algorithms for fully dynamic all-pairs shortest paths

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Frontiers of Computer Science 2024年第4期18卷 201-203页

作者： Chilei WANG Qiang-Sheng HUA Hai jin Chaodong zheng National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory for Novel Software Technology Nanjing UniversityNanjing 210023China

1 Introduction In recent years,the Massively Parallel Computation(MPC)model has gained significant ***,most of distributed and parallel graph algorithms in the MPC model are designed for static graphs[1].In fact,the graphs in the real world are constantly *** size of the real-time changes in these graphs is smaller and more *** graph algorithms[2,3]can deal with graph changes more efficiently[4]than the corresponding static graph ***,most studies on dynamic graph algorithms are limited to the single machine ***,a few parallel dynamic graph algorithms(such as the graph connectivity)in the MPC model[5]have been proposed and shown superiority over their parallel static counterparts.

关键词： dynamic shortest gained

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Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1557-1565页

作者： jin-Xi Zhang Kai-Di xu Qing-Guo Wang IEEE the State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087 Guangdong Key Laboratory of Artificial Intelligence and Multi-Modal Data Processing Beijing Normal University-Hong Kong Baptist University United International CollegeZhuhai 519087

The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this ***, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings.

关键词： Nonlinear systems output constraints prescribed performance reference tracking time delays

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Study of wrist-ankle acupuncture therapy for optimizing anaesthesia scheme of painless gastroscopy and improving painless gastroscopy related complications

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World Journal of Gastrointestinal Endoscopy 2023年第2期15卷 56-63页

作者： Li-Yan zheng Sui-Cai Mi Ling-Yan Wu zheng-jin xu Hao Lu Department of Anesthesiology Xiamen Hospital of Traditional Chinese MedicineXiamen 361000Fujian ProvinceChina Department of Oncology Xiamen Hospital of Traditional Chinese MedicineXiamen 361000Fujian ProvinceChina Department of Nephropathy Xiamen Hospital of Traditional Chinese MedicineXiamen 361000Fujian ProvinceChina Department of Nephrology Xiamen Hospital of Traditional Chinese MedicineXiamen 361000Fujian ProvinceChina Department of Hepatobiliary and Pancreatic Surgery Xiamen Hospital of Traditional Chinese MedicineXiamen 361000Fujian ProvinceChina

BACKGROUND Painless gastroscopy is a widely used diagnostic and therapeutic technology in clinical *** combined with opioids is a common drug for painless endoscopic sedation and *** clinical work,adverse drug reactions of anaesthesia schemes are often one of the important areas of concern for doctors and *** the increase in propofol dosage,the risk of serious adverse drug reactions,such as respiratory depression and hypotension,increases significantly;the use of opioids often causes gastrointestinal reactions in patients after examination,such as nausea,vomiting,delayed recovery of gastrointestinal function and other complications,which seriously affect their quality of *** To observe the effect of wrist-ankle acupuncture therapy on the anaesthesia regimen and anaesthesia-related complications during and after painless gastroscopy *** Two hundred patients were selected and randomly divided into a treatment group(n=100)and a control group(n=100).Both groups were routinely anaesthetized with the nalbuphine and propofol regimen,gastroscopy began after the patient lost consciousness,and given supportive treatment and vital sign *** the patient interrupted the surgery due to intraoperative torsion,intravenous propofol was used to relieve his or her *** treatment group received wrist-ankle acupuncture on this *** The general data before treatment,American Society of Anesthesiologist(ASA)grade and operation time between the two groups was no significant *** Wakeup time,and the Selfambulation time in the treatment group was significantly faster than that in the control group(P<0.05).The total dose of propofol in the treatment group was 109±8.17 mg,significantly lower than that in the control group(P<0.05).The incidence of respiratory depression and hypotension was not significantly different,but the incidence of hiccups was significantly lower than that in the control group(P<

关键词： Wrist-ankle acupuncture therapy Acupuncture anaesthesia Painless gastroscopy Gastroscopy Anaesthesia-related complications

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Effect of an Airbag-selective Portal Vein Blood Arrester on the Liver after Hepatectomy:A New Technique for Selective Clamping of the Portal Vein

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Current Medical Science 2024年第2期44卷 380-390页

作者： Ce-xiong FU Xiao-ri QIN jin-song CHEN Jie ZHONG Yu-xu XIE Bi-dan LI Qing-qing FU Fang LI jin-fang zheng Department of Hepatobiliary and Pancreatic Surgery Hainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou 570311China University of South China Hengyang 421001China Department of Gastroenterology Gastroenterology Endoscopy CenterHainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou 57031lChina Center of Clinical Laboratory Hainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou 570311China Department of Radiology Hainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou 570311China

Objective:A novel technique was explored using an airbag-selective portal vein blood arrester that circumvents the need for an intraoperative assessment of anatomical variations in patients with complex intrahepatic space-occupying ***:Rabbits undergoing hepatectomy were randomly assigned to 4 groups:intermittent portal triad clamping(PTC),intermittent portal vein clamping(PVC),intermittent portal vein blocker with an airbag-selective portal vein blood arrester(APC),and without portal blood occlusion(control).Hepatic ischemia and reperfusion injury were assessed by measuring the 7-day survival rate,blood loss,liver function,hepatic pathology,hepatic inflammatory cytokine infiltration,hepatic malondialdehyde levels,and proliferating cell nuclear antigen ***:Liver damage was substantially reduced in the APC and PVC *** APC animals exhibited transaminase levels similar to or less oxidative stress damage and inflammatory hepatocellular injury compared to those exhibited by the PVC *** was significantly higher in the control group than in the other *** APC group had less bleeding than the PVC group because of the avoidance of portal vein skeletonization during ***,more operative time was saved in the APC group than in the PVC ***,the total 7-day survival rate in the APC group was higher than that in the PTC ***:Airbag-selective portal vein blood arresters may help protect against hepatic ischemia and reperfusion injury in rabbits undergoing partial *** technique may also help prevent liver damage in patients requiring hepatectomy.

关键词： hepatectomy portal vein hepatic damage selective clamping

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HCRVD: A Vulnerability Detection System Based on CST-PDG Hierarchical Code Representation Learning

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Computers, Materials & Continua 2024年第6期79卷 4573-4601页

作者： Zhihui Song jinchen xu Kewei Li zheng Shan School of Cyberspace Security Information Engineering UniversityZhengzhou450001China

Prior studies have demonstrated that deep learning-based approaches can enhance the performance of source code vulnerability detection by training neural networks to learn vulnerability patterns in code ***,due to limitations in code representation and neural network design,the validity and practicality of the model still need to be ***,due to differences in programming languages,most methods lack cross-language detection *** address these issues,in this paper,we analyze the shortcomings of previous code representations and neural *** propose a novel hierarchical code representation that combines Concrete Syntax Trees(CST)with Program Dependence Graphs(PDG).Furthermore,we introduce a Tree-Graph-Gated-Attention(TGGA)network based on gated recurrent units and attention mechanisms to build a Hierarchical Code Representation learning-based Vulnerability Detection(HCRVD)*** system enables cross-language vulnerability detection at the *** experiments show that HCRVD surpasses many competitors in vulnerability detection *** benefits from the hierarchical code representation learning method,and outperforms baseline in cross-language vulnerability detection by 9.772%and 11.819%in the C/C++and Java datasets,***,HCRVD has certain ability to detect vulnerabilities in unknown programming languages and is useful in real open-source *** shows good validity,generality and practicality.

关键词： Vulnerability detection deep learning CST-PDG code representation tree-graph-gated-attention network cross-language

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Liquid lens based holographic camera for real 3D scene hologram acquisition using end-to-end physical model-driven network

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Light(Science & Applications) 2024年第3期13卷 488-497页

作者： Di Wang Zhao-Song Li Yi zheng You-Ran Zhao Chao Liu jin-Bo xu Yi-Wei zheng Qian Huang Chen-Liang Chang Da-Wei Zhang Song-Lin Zhuang Qiong-Hua Wang School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China

With the development of artificial intelligence,neural network provides unique opportunities for holography,such as high fidelity and dynamic *** to obtain real 3D scene and generate high fidelity hologram in real time is an urgent ***,we propose a liquid lens based holographic camera for real 3D scene hologram acquisition using an end-to-end physical model-driven network(EEPMD-Net).As the core component of the liquid camera,the first 10 mm large aperture electrowetting-based liquid lens is proposed by using specially fabricated *** design of the liquid camera ensures that the multi-layers of the real 3D scene can be obtained quickly and with great imaging *** EEPMD-Net takes the information of real 3D scene as the input,and uses two new structures of encoder and decoder networks to realize low-noise phase *** comparing the intensity information between the reconstructed image after depth fusion and the target scene,the composite loss function is constructed for phase optimization,and the high-fidelity training of hologram with true depth of the 3D scene is realized for the first *** holographic camera achieves the high-fidelity and fast generation of the hologram of the real 3D scene,and the reconstructed experiment proves that the holographic image has the advantage of low *** proposed holographic camera is unique and can be used in 3D display,measurement,encryption and other fields.

关键词： calculation solution holographic

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A new scheme of climate-vegetation regionalization in the Hengduan Mountains Region

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Science China Earth Sciences 2024年第3期67卷 751-768页

作者： xueqin ZHANG Xiaoming xu Xiang LI Peng CUI Du zheng Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences-Higher Education Commission of PakistanIslamabad 45320Pakistan

The Hengduan Mountains Region(HMR) is essential for the future ecological protection, clean energy production,Sichuan-Xizang and Yunnan-Xizang railways, and other major infrastructure projects in China. The distributions of climate and vegetation exhibit significant regional differentiation and vertical zonality due to the rugged longitudinal ranges and gorges and the complex disaster-prone environments in HMR. Therefore, it is urgent to develop the climate-vegetation regionalization in HMR to effectively satisfy the national requirements such as agricultural production and ecological protection, mountain disaster risk prevention, and major project construction. We here develop a new scheme of climate-vegetation regionalization with the latest demarcation outcome of HMR, the ground observation from 122 meteorological stations in HMR and its surrounding areas during 1990–2019, and the high-precision remote sensing data of land cover types. The new scheme first constructs the regionalization index system, fully considering the extraordinarily complicated geomorphic pattern of mountains and valleys, the scarcity of meteorological observations, and the remarkable differentiation of climate and vegetation in HMR. The system consists of three primary regionalization indices(i.e., days with daily average temperature steady above 10°C, aridity index, and main vegetation types, dividing the temperature zones, moisture regions, and vegetation subregions, respectively) and three auxiliary indices of the accumulated temperature above 10°C, and the temperatures in January and July. Then, the HMR is divided into five temperature zones, 20 moisture regions, and 55 vegetation subregions. Compared with previous regionalization schemes, the new scheme optimizes the climate spatial interpolation model of thin plate smoothing spline suitable for the unique terrain in HMR. Moreover, the disputed division index threshold between different climatic zones(regions) is scientifically clarifi

关键词： Climate-vegetation regionalization Thin plate smoothing spline(TPSS) GeoDetector Stepwise downscaling pane division method Hengduan Mountains Region

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Ultrasound-driven self-decomposition porphyrins as metal-free CO precursors for gas and sonodynamic synergistic therapy

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Science China Chemistry 2024年第5期67卷 1624-1635页

作者： Shuxin Liu jinjuan Ma Xiang xu Aiguo Wang Nan zheng School of Chemical Engineering Dalian University of TechnologyDalian 116024China Department of Comparative Medicine Laboratory Animal Center Dalian Medical UniversityDalian 116000China Cancer Hospital of Dalian University of Technology Shenyang 116000China

Carbon monoxide(CO) is an endogenous therapeutic gas with an anti-tumor effect. The precise delivery and controlled release of CO in tumor tissues play crucial roles in anti-cancer treatment. However, efficient in situ generation of CO from metal-free COreleasing molecules(CORMs) remains a formidable challenge. Herein, we develop ultrasound(US)-driven self-decomposition porphyrin as organic and metal-free US-CORMs, which can spatiotemporally control the CO release(347 mmol CO/mol porphyrin) efficiently under physiologically harmless US conditions(1.0 MHz, 1.5 W/cm^(2), 50% duty cycle, 50 min). Moreover,porphyrin as a sonosensitizer can also generate reactive oxygen species(ROS) under US treatment to achieve sonodynamic therapy(SDT). Advanced functions of such porphyrin-based CORMs in CO gas-sonodynamic synergistic treatment have been demonstrated by evaluating the in vitro and in vivo anti-tumor effects.

关键词： porphyrin sonodynamic therapy metal-free CO precursors ultrasound-driven gas therapy

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Variational quantum algorithms for scanning the complex spectrum of non-Hermitian systems

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Frontiers of physics 2024年第4期19卷 275-285页

作者： xu-Dan Xie zheng-Yuan xue Dan-Bo Zhang Key Laboratory of Atomic and Subatomic Structure and Quantum Control(Ministry of Education) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matterand School of PhysicsSouth China Normal UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials Guangdong–Hong Kong Joint Laboratory of Quantum Matterand Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China

Solving non-Hermitian quantum many-body systems on a quantum computer by minimizing the variational energy is challenging as the energy can be ***,we propose a variational quantum algorithm for solving the non-Hermitian Hamiltonian by minimizing a type of energy variance,where zero variance can naturally determine the eigenvalues and the associated left and right ***,the energy is set as a parameter in the cost function and can be tuned to scan the whole spectrum efficiently by using a two-step optimization *** numerical simulations,we demonstrate the algorithm for preparing the left and right eigenstates,verifying the biorthogonal relations,as well as evaluating the *** also investigate the impact of quantum noise on our algorithm and show that its performance can be largely improved using error mitigation ***,our work suggests an avenue for solving non-Hermitian quantum many-body systems with variational quantum algorithms on near-term noisy quantum computers.

关键词： quantum algorithm non-Hermitian physics quantum manybody systems

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