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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 *** 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 *** makes it a wide range of harms.A variety of security technologies have been proposed to deal with system security problems including buffer *** example,No eXecute(NX for short)is a memory management technology commonly used in Harvard *** can refuse the execution of code which residing in a specific memory,and can effectively suppress the abnormal impact of buffer overflow on control ***,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,***,these security solutions often rely too much on the processor archi-tecture so that the protection coverage is insufficient and the accuracy is *** in the emerging system architecture field represented by RiSC-V,there is still a lack of effective solutions for buffer overflow *** 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 ***,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 *** 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

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

Pion-photon and kaon-photon transition distribution amplitudes in the Nambu–Jona-Lasinio model

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Chinese Physics C 2024年第8期48卷 94-103页

作者： Jin-Li Zhang jun wu Department of Mathematics and Physics Nanjing Institute of TechnologyNanjing 211167China National Laboratory of Solid State Microstructures Department of PhysicsNanjing UniversityNanjing 210093China

The Nambu–Jona-Lasinio model is utilized to investigate the pion-and kaon-photon leading-twist transition distribution amplitudes using proper time ***,the properties of the vector and axial vector pion-photon transition distribution amplitudes are examined,and the results meet the desired *** study involves sum rule and polynomiality *** vector and axial vector pion-photon transition form factors that are present in theπ^(+)→γe^(+)νprocess are the first Mellin moments of the pion-photon transition distribution *** vector transition form factor originates from the internal structure of hadrons,the axial current can be coupled to a pion,this pion is virtual,and its contribution will be present independently of the external *** kaon transition form factors are *** vector form factor's value at zero momentum transfer is determined by the axial anomaly,while this is not the case for the axial *** vector and axial form factors,as well as the neutral pion vector form factor F_(πγγ)(t),are *** to our findings,the pion axial transition form factor is harder than the vector transition form factor and harder than the electromagnetic form *** also discuss the link betweenπ−γandγ−πtransitions distribution amplitudes.

关键词： transition form factors NJL model transition distribution amplitudes

Impact response and energy absorption of metallic buffer with entangled wire mesh damper

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Defence Technology（防务技术） 2024年第5期35卷 137-150页

作者： Chao Zheng jun wu Mangong Zhang Xin Xue Institute of Metal Rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350116China wuhan Second Ship Design and Research Institute Wuhan 430205China

An innovative metallic buffer consisting of series-connected hat-shaped entangled wire mesh damper(EWMD)and parallel springs are proposed in this work to enhance the reliability of engineering *** impact response and the energy dissipation mechanism of hat-shaped EWMD under different quasi-static compression deformations(2-7 mm)and impact heights(100-200 mm)are investigated using experimental and numerical *** results demonstrate distinct stages in the quasi-static mechanical characteristics of hat-shaped EWMD,including stiffness softening,negative stiffness,and stiffness *** loss factor gradually increases with increasing compression deformation before entering the stiffness hardening *** impact loads,the hat-shaped EWMD exhibits optimal impact energy absorption when it enters the negative stiffness stage(150 mm),resulting in the best impact isolation effect of metallic ***,the impact energy absorption significantly decreases when hat-shaped EWMD enters the stiffness hardening ***,quasi-static compression analysis after experiencing different impact loads reveals the disappearance of the negative stiffness ***,with increasing impact loads,the stiffness hardening point progressively shifts to an earlier stage.

关键词： Metallic buffer Hat-shaped EWMD Drop impact Energy absorption characteristics Mechanical behavior

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Diabetes remission and nonalcoholic fatty pancreas disease

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World Journal of Diabetes 2024年第7期15卷 1390-1393页

作者： Wen-jun wu Department of Endocrinology Jinshan Branch of Shanghai Sixth People’s HospitalShanghai 201500China

This editorial focuses on the relationship between nonalcoholic fatty pancreas disease(NAFPD)and the development and remission of type 2 diabetes(T2D).NAFPD is characterized by intrapancreatic fatty deposition associated with obesity and not associated with alcohol abuse,viral infections,and other *** fat deposition in the pancreas is associated with the development of T2D,and the underlying mechanism is lipotoxicβ-cell ***,the results on the relationship between intrapancreatic fat deposition(IPFD)andβ-cell function are *** of the therapeutic approach,weight loss improves IPFD,glycemia,andβ-cell *** imaging is valuable for clinically monitoring and evaluating the management of T2D.

关键词： Diabetes remission Type 2 diabetes Pancreatic fat content βcell function Weight loss

Macroscopic model and statistical model to characterize electromagnetic information of a digital coding metasurface

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National Science Review 2024年第3期11卷 159-171页

作者： Rui Wen Shao jun Wei wu Zheng Xing Wang Hui Xu Han Qing Yang Qiang Cheng Tie jun Cui Institute of Electromagnetic Space Southeast University State Key Laboratory of Millimeter Waves Southeast University Peng Cheng Laboratory Pazhou Laboratory(Huangpu)

A digital coding metasurface is a platform connecting the digital space and electromagnetic wave space, and has therefore gained much attention due to its intriguing value in reshaping wireless channels and realizing new communication architectures. Correspondingly, there is an urgent need for electromagnetic information theory that reveals the upper limit of communication capacity and supports the accurate design of metasurface-based communication systems. To this end, we propose a macroscopic model and a statistical model of the digital coding metasurface. The macroscopic model uniformly accommodates both digital and electromagnetic aspects of the meta-atoms and predicts all possible scattered fields of the digital coding metasurface based on a small number of simulations or measurements. Full-wave simulations and experimental results show that the macroscopic model is feasible and accurate. A statistical model is further proposed to correlate the mutual coupling between meta-atoms with covariance and to calculate the entropy of the equivalent currents of digital coding metasurface. These two models can help reconfigurable intelligent surfaces achieve more accurate beamforming and channel estimation, and thus improve signal power and coverage. Moreover, the models will encourage the creation of a precoding codebook in metasurface-based direct digital modulation systems, with the aim of approaching the upper limit of channel capacity. With these two models, the concepts of current space and current entropy, as well as the analysis of information loss from the coding space to wave space, is established for the first time, helping to bridge the gap between the digital world and the physical world, and advancing developments of electromagnetic information theory and new-architecture wireless systems.

关键词： electromagnetic information theory current entropy current space digital coding metasurface macroscopic model statistical model

The nature of electron density enhancement over a wide altitude range during ionosphere heating experiments at EISCAT

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Earth and Planetary Physics 2024年第2期8卷 408-414页

作者： jun wu Jian wu Jie Feng QingLiang Li ShuJi Hao ZhengWen Xu HaiSheng Zhao YaBin Zhang National Key Laboratory of Electromagnetic Environment China Research Institute of Radio Wave PropagationBeijing 102206China School of Physics Xidian UniversityXi’an 710071China

During the course of ionospheric heating experiments, researchers at the European Incoherent Scatter Scientific Association (EISCAT) observed an apparent electron density enhancement. The enhancement extended over a wide range of altitudes, above the reflection altitude of the high-frequency pump wave. However, whether this enhancement actually corresponds to a true enhancement in electron density remains an open question. When the dispersion relation of ion acoustic waves is followed, the frequency ratio of the enhanced ion line to the background ion line suggests that the profile of the effective ion mass may have remained unchanged. Furthermore, the solar radio flux and ion drift velocity indicate no significant changes in the ion species and their densities. In conclusion, the electron density enhancement observed at EISCAT should not, in fact, be considered a true enhancement.

关键词： incoherent scatter radar(ISR) ionospheric heating electron density ion acoustic wave

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Geochemical identification of a source rock affected by migrated hydrocarbons and its geological significance:Fengcheng Formation,southern Mahu Sag,junggar Basin,NW China

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Petroleum Science 2024年第1期21卷 100-114页

作者： Wen-Long Dang Gang Gao Xin-Cai You Ke-Ting Fan jun wu De-Wen Lei Wen-jun He Yong Tang State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum(Beijing)Beijing102249China School of GeoSciences China University of Petroleum(Beijing)Beijing102249China Exploration&Development Institute Xinjiang Oil Field CompanyKaramay834000XinjiangChina

The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu *** oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of the sag in the southern Mahu *** crude oils originate from in-situ source rocks in shallowly buried areas and the inner deep *** migration,the crude oil from the inner deep sag affects the source rocks close to carrier beds,leading to changes in the organic geochemical characteristics of the source *** changes might alter source rock evaluations and oil-source *** on data such as total organic carbon(TOC),Rock-Eval pyrolysis of source rocks,and gas chromatography-mass spectrometry(GC-MS)of the saturated fraction,and considering the geological characteristics of the study area,we define the identification characteristics of source rock affected by migrated hydrocarbons and establish the various patterns of influence that migrated hydrocarbons have on the source rock of the Fengcheng Formation in the southern Mahu *** source rocks of the Fengcheng Formation are mostly fair to good,containing mainly Type II organic matter and being thermally mature enough to generate *** rocks affected by migrated hydrocarbons exhibit relatively high hydrocarbon contents(S1/TOC>110 mg HC/g TOC,Extract/TOC>30%,HC:hydrocarbon),relatively low Rock-Eval Tmax values,and relatively high tricyclic terpane contents with a descending and mountain-shaped ***,biomarker composition parameters indicate a higher thermal maturity than in-situ source *** a comparison of the extract biomarker fingerprints of adjacent reservoirs and mudstones in different boreholes,three types of influence patterns of migrated hydrocarbons are identified:the edge-influence of thin sandstone-thick mudstone,the mixed-influence of sandstone-mudstone interbedded,and the full-influence of thick sandstone-thin *** finding reminds

关键词： Organic geochemistry Source rock Influence of migrated hydrocarbons Fengcheng Formation Southern Mahu Sag

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Effect of health education based on information-motivationbehavioral skills model on patients with unilateral vestibular dysfunction

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World Journal of Clinical Cases 2024年第5期12卷 903-912页

作者： Qiong Shi Ruo-jun wu Jiang Liu Department of Neurology Wuahan Fourth HospitalWuhan 430000Hubei ProvinceChina Department of Critical Care Medicine Wuhan No.1 HospitalWuhan 430033Hubei ProvinceChina

BACKGROUND Vestibular dysfunction(VH)is a common concomitant symptom of late peri-pheral vestibular lesions,which can be trauma,poisoning,infection,heredity,and neurodegeneration,but about 50%of the causes are *** study uses the information-motivation-behavioral skills(IMB)model for health education,effectively improve the quality of life,increase their self-confidence,reduce anxiety and depression,and effectively improve the psychological state of *** To explore the effect of health education based on the IMB model on the degree of vertigo,disability,anxiety and depression in patients with unilateral vestibular *** The clinical data of 80 patients with unilateral vestibular hypofunction from January 2019 to December 2021 were selected as the retrospective research objects,and they were divided into the control group and the observation group with 40 cases in each group according to different nursing *** them,the control group was given routine nursing health education and guidance,and the observation group was given health education and guidance based on the IMB *** changes in self-efficacy,anxiety and depression,and quality of life of patients with unilateral VH were compared between the two *** There was no significant difference in General Self-Efficacy Scale(GSES)scale scores between the two groups of patients before nursing(P>0.05),which was comparable;after nursing,the GSES scale scores of the two groups were higher than those before *** nursing group was higher than the control group,and the difference was statistically significant(P0.05).After nursing,the HADS score,anxiety,and depression subscale scores of the two groups of patients were lower than those before nursing,and the nursing group was lower than the co

关键词： Information-motivation-behavioral skills model Health education Vestibular function Quality of life Selfefficacy

Simultaneous type III congenital esophageal atresia and patent ductus arteriosus in a low-weight patient: A case report

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World Journal of Clinical Cases 2024年第3期12卷 560-564页

作者： Yong-Yu Ma jun-Ru Chen Shi-wu Yang Shu-Yu Wang Xin Cao jun wu Faculty of Pediatrics Children’s Hospital Affiliated to Kunming Medical UniversityKunming 650103Yunnan ProvinceChina Department of Cardiothoracic Surgery Kunming Children’s HospitalKunming 650103Yunnan ProvinceChina

BACKGROUND We report a low-birth-weight child(1.8 kg)with neonatal type III congenital esophageal atresia(CEA)combined with symptomatic patent ductus arteriosus(PDA).After comprehensive evaluation,esophageal anastomosis was performed on postnatal day 11 after excluding surgical contraindications,and arterial catheter ligation was performed at the same *** surgery for CEA combined with PDA has not been clearly reported in the *** SUMMARY We report a 6-day-old female child with type III CEA and *** patient presented with foam at the mouth after birth,cough and shortness of breath after *** another hospital,she was considered to have neonatal pneumonia,neonatal jaundice and congenital heart disease and transferred to our *** iodine oil radiography of the esophagus and echocardiography we con-firmed diagnosis of CEA and *** diameter of the PDA was 8 mm,with obvious left to right *** performed right rear extrapleural orificium fistula ligation and esophageal anastomosis,and ligation of PDA via left axilla straight incision after 5 d of *** operations were successful,and the incision healed after 12 d,and the patient was *** re-examined the patient 1 mo after *** did not vomit when she ate rice *** angiography showed no stricture of the anastomotic *** patient weighed 3.2 *** For CEA patients with multiple risk factors,comprehensive,timely and accurate diagnosis and evaluation,and early treatment may improve prognosis.

关键词： Congenital esophageal atresia Patent ductus arteriosus Low weight One-stage operation Case report