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PETROLEUM SCIENCE 2024年第2期21卷 1171-1189页

作者： Zhang, Kun-Peng Chen, Mian zhao, chang-jun Wang, Su Fan, Yong-Dong China Univ Petr State Key Lab Petr Resources & Prospecting Beijing 102249 Peoples R China China Univ Petr MOE Key Lab Petr Engn Beijing 102249 Peoples R China Peking Univ Beijing Int Ctr Gas Hydrate Sch Earth & Space Sci Beijing 100871 Peoples R China

A method for in -situ stress measurement via fiber optics was proposed. The method utilizes the relationship between rock mass elastic parameters and in -situ stress. The approach offers the advantage of long -term stress measurements with high spatial resolution and frequency, significantly enhancing the ability to measure in -situ stress. The sensing casing, spirally wrapped with fiber optic, is cemented into the formation to establish a formation sensing nerve. Injecting fluid into the casing generates strain disturbance, establishing the relationship between rock mass properties and treatment pressure. Moreover, an optimization algorithm is established to invert the elastic parameters of formation via fiber optic strains. In the first part of this paper series, we established the theoretical basis for the inverse differential strain analysis method for in -situ stress measurement, which was subsequently verified using an analytical model. This paper is the fundamental basis for the inverse differential strain analysis method. (c) 2024 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY -NC -ND license (http://***/licenses/by-nc-nd/ 4.0/).

关键词： In -situ stress Fiber optic Orthotropic elastic Differential evolution ABAQUS

A buffer overflow detection and defense method based on RiSC-V instruction set extension

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Cybersecurity 2024年第2期7卷 28-43页

作者： chang Liu Yan-jun Wu Jing-Zheng Wu Chen zhao Intelligent Software Research Center Institute of SoftwareChinese Academy of SciencesBejingChina University of Chinese Academy of Sciences BeijingChina State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijingChina

Buffer overflow poses a serious threat to the memory security of modern operating systems.It overwrites the con-tents of other memory areas by breaking through the buffer capacity limit,destroys the system execution environ-ment,and provides implementation space for various system attacks such as program control flow hijacking.That makes it a wide range of harms.A variety of security technologies have been proposed to deal with system security problems including buffer overflow.For example,No eXecute(NX for short)is a memory management technology commonly used in Harvard architecture.It can refuse the execution of code which residing in a specific memory,and can effectively suppress the abnormal impact of buffer overflow on control flow.Therefore,in recent years,it has also been used in the field of system security,deriving a series of solutions based on NX technology,such as ExecShield,DEP,StackGuard,etc.However,these security solutions often rely too much on the processor archi-tecture so that the protection coverage is insufficient and the accuracy is limited.Especially in the emerging system architecture field represented by RiSC-V,there is still a lack of effective solutions for buffer overflow vulnerabilities.With the continuous rapid development of the system architecture,it is urgent to develop defense methods that are applicable to different system application environments and oriented to all executable memory spaces to meet the needs of system security development.Therefore,we propose BOP,A new system memory security design method based on RISC-V extended instructions,to build a RISC-V buffer overflow detection and defense system and deal with the buffer overflow threat in RIsC-V.According to this method,NX technology can be combined with program control flow analysis,and Nx bit mechanism can be used to manage the executability of memory space,so as to achieve a more granular detection and defense of buffer overflow attacks that may occur in RISC-V system environment.In addition,The memory management an

关键词： RISc-V Operating system security Buffer overflow Control flow hijacking Nx bit Xibop

Mechanical properties and microstructure of multilayer graphene oxide cement mortar

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Frontiers of Structural and Civil Engineering 2021年第4期15卷 1058-1070页

作者： jun LIU Luxi zhao Fei chang Lin CHI School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai200093China

This study reports on the effects of multilayer graphene oxide(MGO)on compressive strength,flexural strength,and microstructure of cement mortar.The cement mortar was prepared with type P.II.52.5 Portland cement,standard sand,and MGO.Four mixes were prepared with inclusion of MGO(0%,0.02%,0.04%,and 0.06%by weight of cement).The testing result shows that the compressive of GO-cement mortar increased by 4.84%–13.42%,and the flexural strength increased by 4.37%–8.28%at 3 d.GO-cement mortar’s compressive strength and flexural strength at 7 d increased by 3.84%–12.08%and 2.54%–13.43%,respectively.MGO made little contribution to the increases of compressive strength and flexural strength of cement mortar at 28 d.The results of X-ray diffraction(XRD),scanning electron microscope(SEM),and nitrogen(N2)adsorption/desorption tests show that the types of hydration products and crystal grain size did not change after adding MGO.Still,it can help to improve the microstructure of the cement mortar via regulating hydration products and can provide more condensed cores to accelerate hydration.Furthermore,the regulating action of MGO for the microstructure of cement mortar at an early age was better than that at 28 d.

关键词： graphene oxide cement mortar mechanical properties microstructure

SCIM: Incorporating secure communication and interference management in one operation

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Digital Communications and Networks 2023年第2期9卷 512-522页

作者： zhao Li Pintian Lyu jun Li Zhixian chang Jia Liu Zheng Yan School of Cyber Engineering Xidian UniversityXi'an710126China Technol.on Commun.Net.Lab The 54th Research Inst.of China Elec.Technol.Group CorpShijiazhuang050081China School of Telecommun.and Inf.Engineering Xi'an University of Posts&TelecommunXi'an710071China School of Computer Science and Technology Xidian UniversityXi'an710126China The Department of Comnet Aalto UniversityEspoo02150Finland

Due to the broadcast nature of wireless communications,users’data transmitted wirelessly is susceptible to security/privacy threats.Meanwhile,as a result of the limitation of spectrum resources,massive wireless connections will incur serious interference,which may damage the efficiency of data transmission.Therefore,improving both efficiency and secrecy of data transmission is of research significance.In this paper,we propose a wireless transmission scheme by taking both Secure Communication(SC)and Interference Management(IM)into account,namely SCIM.With this scheme,an SCIM signal is generated by the legitimate transmitter(Tx)and sent along with the desired signal,so that the SCIM signal can interact with and suppress the environmental interference at the legitimate receiver(Rx).Meanwhile,the SCIM signal may interfere with the eavesdropper in the coverage of legitimate transmission so as to deteriorate the eavesdropping performance.Therefore,the secrecy of desired transmission is improved.In this way,both the transmission efficiency and privacy are enhanced.Then,by taking various transmission preferences into account,we develop different implementations of SCIM,including Interference Suppression First SCIM(ISF-SCIM),Data Transmission First SCIM(DTF-SCIM),Anti-Eavesdropping First SCIM(AEF-SCIM),and Secrecy Rate Maximization SCIM(SRM-SCIM).Our in-depth simulation results have shown the proposed methods to effectively improve the efficiency and secrecy of the legitimate transmission.

关键词： Physical-layer security Secure communication Anti-eavesdropping Interference management Secrecy rate

Preliminary Design of a System for Picking up Audio-Signals From Bubble Detectors GAO Si-ze1,NI Bang-fa,ZHANG Gui-ying,XIAO Cai-jin,LIU Cun-xiong, CHEN Zhe1,NIE Peng,LIU Chao1,ZHAO Chang-jun (1.College of Physics Science and Engineering Technology,Guang

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Preliminary Design of a System for Picking up Audio-Signals ...

Assessing spatial and temporal variability in waterconsumption and the maintainability oasis maximumarea in an oasis region of Northwestern China

作者： GAO Si-ze NI Bang-fa ZHANG Gui-ying XIAO Cai-jin LIU Cun-xiong CHEN Zhe NIE Peng LIU Chao ZHAO Chang-jun College of Physics Science and Engineering Technology Guangxi University

This system is designed to pick up sound signals from large volume,low-threshold energy, low-background superheated droplets bubble detectors.A sound-sensitive bubble detector is composed of a container filled with a mixture of superheated droplets and gel,a temperature and pressure control system,and an audio acquisition system attached on the outer surface of the container.The superheated droplets are in a metastable and superheated state at ambient temperature and pressure.When the outside

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Research in Cold and Arid Regions 2020年第4期12卷 217-233页

作者： XueXiang chang WenZhi zhao XueLi chang Bing Liu jun Du Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLinze Inland River Basin Research StationKey Laboratory of Ecohydrology of Inland River BasinCASLanzhouGansu 730000China School of Natural Resources and Environmental Engineering Ludong UniversityYantaiShandong 264025China

Water consumption is a key role in improving the efficiency and sustainability of water management in arid environments.In this study, we explored an approach based on meta-analysis, MODIS NDVI products, land-use spatial distribution, andsoil water physical parameters to gain insight into long-term and large scale distribution of land use and water consumption,maintain maximum Zhangye Oasis area according to Heihe River runoff, and suitable water resource management inZhangye Oasis. This approach was initiated in order to improve the efficiency of irrigation and water resource managementin arid regions. Results showed that Heihe River runoff can maintain a maximum Zhangye Oasis area of 22.49×104 hm2.During the 2000−2016 growing seasons, actual oasis water consumption ranged from 11.35×108 m3 to 13.73×108 m3, witha mean of (12.89 ± 0.60)×108 m3;if maintaining agricultural production and oasis stability was chosen, oasis water consumptionranged from 10.24×108 m3 to 12.37×108 m3, with a mean of (11.62 ± 0.53)×108 m3. From the perspective of waterresources management and ecosystem stability, it is necessary to reduce the area of Zhangye Oasis or choose the minimumwater consumption method to manage the oasis, to ease the pressure of water shortage and maintain stable and sustainabledevelopment of the Zhangye Oasis. These results can provide future practical guidance for water resource management ofcoordinated development of the economy and the environment in an arid area.

关键词： meta-analysis water consumption land-use spatial and temporal distribution runoff Northwestern China

CBN grain wear and its effects on material removal during grinding of FGH96 powder metallurgy superalloy

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Advances in Manufacturing 2023年第1期11卷 21-38页

作者： Ben-Kai Li Biao zhao Wen-Feng Ding Yu-Can Fu chang-He Li Rong Wang Yan-jun zhao National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao266525ShandongPeople’s Republic of China Aecc Xi’an Aero-engine Ltd Xi’an710021People’s Republic of China State Key Laboratory of Superabrasives Zhengzhou Research Institute for Abrasive and GrindingZhengzhou450001People’s Republic of China

Grinding with cubic boron nitride(CBN)superabrasive is a widely used method of machining superalloy in aerospace industries.However,there are some issues,such as poor grinding quality and severe tool wear,in grinding of powder metallurgy superalloy FGH96.In addition,abrasive wheel wear is the significant factor that hinders the further application of CBN abrasive wheels.In this case,the experiment of grinding FGH96 with single CBN abrasive grain using different parameters was carried out.The wear characteristics of CBN abrasive grain were analyzed by experiment and simulation.The material removal behavior affected by CBN abrasive wear was also studied by discussing the pile-up ratio during grinding process.It shows that morphological characteristics of CBN abrasive grain and grinding infeed direction affect the CBN abrasive wear seriously by simulation analysis.Attrition wear,micro break,and macro fracture had an important impact on material removal characteristics.Besides,compared with the single cutting edge,higher pile-up ratio was obtained by multiple cutting edges,which reduced the removal efficiency of the material.Therefore,weakening multiple cutting edge grinding on abrasive grains in the industrial production,such as applying suitable dressing strategy,is an available method to improve the grinding quality and efficiency.

关键词： FGH96 powder metallurgy superalloy Single-grain grinding Cubic boron nitride(CBN)abrasive wear Material removal behavior

Effects of moxibustion on Treg cells in sarcoma microenvironment

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Journal of Integrative Medicine 2021年第3期19卷 251-257页

作者： Li-jun Li Yu-chong Shi Min-xiang Luo chang-lin zhao Department of Acupuncture Guangdong Clifford HospitalGuangzhou 511495Guangdong ProvinceChina School of Traditional Chinese Medicine Jinan UniversityGuangzhou 510632Guangdong ProvinceChina Health Science College Guangdong Pharmaceutical UniversityGuangzhou 510006Guangdong ProvinceChina

Objective:To investigate the therapeutic effect of moxibustion on sarcomas from mesenchymal tissues,which have a low response rate to chemotherapy and radiotherapy.Methods:S180 sarcoma cell line was inoculated in C57 BL/6 mice to form transplanted tumor.Moxibustion therapy was directly applied at the transplanted tumor sites,at a distance of 3.0 cm,10 min per session,till skin temperature reached 45°C,once a day,for 14 consecutive days of intervention.After the mice were killed,serum was collected and used to detect concentrations of interleukin-10(IL-10),transforming growth factor-b1(TGF-b1),IL-4 and interferon-c(IFN-c)by Luminex liquid suspension chip.The numbers of Treg^(^(+) )T cells and CD4^(+) CD25^(+) Forkhead Box P3(Foxp3)^(+) T cells were detected by flow cytometry.Fluorescence in situ hybridization was used to analyze the changes of CD4,CD8,Foxp3 and TGF-b1 in the tumor microenvironment(TME).Results:Weight of S180 transplanted tumor in the control group was(2.03±0.54)g,and that in the moxibustion group was(1.27±0.29)g,which was statistically different(P=0.023).The mean value of Foxp3^(+) T cells in the normal group was 2.01%,which increased to 3.63%after the formation of transplanted tumor,and decreased to 1.48%after moxibustion treatment.The moxibustion group also had reduced numbers of CD4^(+) CD25^(+) Foxp3^(+) T cells in the spleen of mice with transplanted tumor.The concentrations of IL-10,TGF-b1 and IL-4 decreased in the serum of mice with transplanted tumor,while the concentration of IFN-c increased.Moxibustion was associated with downregulation in expression of Foxp3,IL-10 and TGF-b1 genes in the transplanted tumor,and increases in the gene expression of CD4^(+) T cells and CD8^(+) T cells in the TME.Conclusion:Moxibustion may have therapeutic effects on sarcomas by reducing the number of Treg cells in the blood and controlling the infiltration of Treg cells in the TME.

关键词： Sarcoma Moxibustion Treg cells Tumor microenvironment

Acupoint catgut embedding for simple obesity in animal studies:a systematic review and Meta-analysis

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中医杂志:英文版 2023年第5期43卷 860-867页

作者： zhao HuiYan jun Purumea LEE Chaewon HAN chang-Hyun Korean Convergence Medical Science University of Science and Technology(UST)School of Korea Institute of Oriental MedicineDaejeon 34054Republic of Korea KM Science Research Division Korea Institute of Oriental MedicineDaejeon 34054Republic of Korea KM Data Division Korea Institute of Oriental MedicineDaejeon 34054Republic of Korea St.Johnsbury Academy Jeju 304Global edu-roDaejeong-eupSeogwipo-si 63644Republic of Kore

OBJECTIVE:To assess the efficacy of acupoint catgut embedding(ACE)for simple obesity in preclinical animal experiments.METHODS:We searched the following 14 electronic databases:PubM ed,Cochrane Library,EMBASE,Oriental Medicine Advanced Searching Integrated System,KoreaMed,Korean Studies Information Service System,Science-on,Research Information Sharing Service,Korea Citation Index,Korea Traditional Knowledge Portal,China Network Knowledge Infrastructure Database,Wanfang Database,Chinese Science and Technology Journal Database,and Chinese Biology Medicine Database,from inception to November 2021 without language limitation.The assessment was performed according to the guidelines of Animal Research:Reporting of in vivo experiments;and Metaanalysis was performed using Reviewer Manager 5.4.1 software.RESULTS:Twenty-four studies involving 813 animals were selected.Meta-analysis showed that ACE was beneficial for weight control[n=40,MD=-50.63,95%CI(-57.59,-43.67),P<0.00001,I 2=0%]and reduced the Lee index[n=40,MD=-18.79,95%CI(-20.01,-17.57),P<0.00001,I 2=0%].However,when efficacy of ACE was compared with that of manual acupuncture,electroacupuncture,or oilistat therapy,statistical difference was not observed between the two groups.CONCLUSIONS:This systematic review suggests that ACE may be efficacious in treating obesity.Moreover,the analyses highlighted the necessity to perform welldesigned,higher-quality experiments.

关键词： obesity acupoint catgut embedding animal study Meta-analysis systematic review

Effect of electrical parameters and slag system on macrostructure of electroslag ingot

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China Foundry 2024年第1期21卷 44-50页

作者： Bing-jie Wang Yu Wang Meng-jun Wang Lei zhao Li-zhong chang Xiao-fang Shi School of Metallurgy engineering Anhui University of TechnologyMa'anshan 243002AnhuiChina

To investigate the influence of electric parameters and slag system on the solidification quality of electroslag ingot during electroslag remelting,different power supply modes,current strengths and remelting slag systems were used to conduct electroslag remelting experiments on 304L austenitic stainless steel,and the macrostructure of electroslag ingots was analyzed.The results indicate that the depth of the metal pool decreases with the reduction of remelting frequency in the low frequency power supply mode.The effects of different power supply modes,such as low-frequency,direct current straight polarity(DCSP),and direct current reverse polarity(DCRP),on reducing the depth of the metal pool increase in that order.By reducing the remelting current strength in the same power supply mode,the depth of metal pool is reduced.When compared to the binary slag system of 70%CaF2+30%Al2O3,the ternary slag system of 60%CaF2+20%Al2O3+20%CaO is more effective in reducing the depth of the metal pool during remelting.Utilizing the 60%CaF2+20%Al2O3+20%CaO ternary slag system results in a shallower and flatter metal pool,with columnar crystal growth occurring closer to the axial crystal.This effect is observed for both low frequency and direct current(DC)power supply modes.

关键词： electroslag remelting frequency slag system solidification quality