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Permissible Minimum Thickness in Asymmetrical Cold Rolling 被引量:6
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作者 TANG De-lin LIU Xiang-hua +1 位作者 LI Xiang-yu PENG Liang-gui 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2013年第11期21-26,共6页
The minimum rolling thickness in asymmetrical rolling was analyzed compared with that in symmetrical rolling. The differential equilibrium equations on forces were established to calculate the asymmetrical rolling for... The minimum rolling thickness in asymmetrical rolling was analyzed compared with that in symmetrical rolling. The differential equilibrium equations on forces were established to calculate the asymmetrical rolling force equation by slab method. An implicit expression of the minimum rolling thickness was then derived from the rolling force equation and Hitehcock equation. The results show that permissible minimum rolling thickness of asymmetrical rolling only exists within a specific range of cross-shear ratio, which is termed the cross-shear zone proportion of the whole de- formation zone. Numerical computation was carried out to obtain a discrete solution of the minimum rolling thick- ness. Experiments were designed to investigate the influence factors on cross-shear ratio. Finally, experimental re- sults prove the correctness of the improved formula given. 展开更多
关键词 asymmetrical roiling minimum permissible thickness cross-shear ratio asymmetrical ratio friction peak value
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PermissibleWind Conditions for Optimal Dynamic Soaring with a Small Unmanned Aerial Vehicle 被引量:1
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作者 Liu Duo-Neng Hou Zhong-Xi +2 位作者 Guo Zheng Yang Xi-Xiang Gao Xian-Zhong 《Computer Modeling in Engineering & Sciences》 SCIE EI 2016年第6期531-565,共35页
Dynamic soaring is a flight maneuver to exploit gradient wind field to extend endurance and traveling distance.Optimal trajectories for permissible wind conditions are generated for loitering dynamic soaring as well a... Dynamic soaring is a flight maneuver to exploit gradient wind field to extend endurance and traveling distance.Optimal trajectories for permissible wind conditions are generated for loitering dynamic soaring as well as for traveling patterns with a small unmanned aerial vehicle.The efficient direct collection approach based on the Runge-Kutta integrator is used to solve the optimization problem.The fast convergence of the optimization process leads to the potential for real-time applications.Based on the results of trajectory optimizations,the general permissible wind conditions which involve the allowable power law exponents and feasible reference wind strengths supporting dynamic soaring are proposed.Increasing the smallest allowable wingtip clearance to trade for robustness and safety of the vehicle system and improving the maximum traveling speed results in shrunken permissible domain of wind conditions for loitering and traveling dynamic soaring respectively.Sensitivity analyses of vehicle model parameters show that properly reducing the wingspan and increasing the maximum lift-to-drag ratio and the wing loading can enlarge the permissible domain.Permissible domains for different traveling directions show that the downwind dynamic soaring benefitting from the drift is more efficient than the upwind traveling pattern in terms of permissible domain size and net traveling speed. 展开更多
关键词 DYNAMIC SOARING permissible WIND CONDITIONS TRAJECTORY optimization Unmanned AERIAL vehicle(UAV)
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An Ordering Policy for Deteriorating Items with Time-Dependent Quadratic Demand and Salvage Value under Permissible Delay in Payment 被引量:1
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作者 Trailokyanath Singh Madan Mohan Muduly +2 位作者 Chittaranjan Mallick Rahul Kumar Gupta Hadibandhu Pattanayak 《American Journal of Operations Research》 2019年第5期201-218,共18页
The article deals with an economic order quantity (EOQ) inventory model for deteriorating items in which the supplier provides the purchaser a permissible delay in payment. This is so when deterioration of units in th... The article deals with an economic order quantity (EOQ) inventory model for deteriorating items in which the supplier provides the purchaser a permissible delay in payment. This is so when deterioration of units in the inventory is subject to constant deterioration rate, demand rate is quadratic function of time and salvage value is associated with the deteriorated units. Shortages in the system are not allowed to occur. A mathematical formulation is developed when the supplier offers a permissible delay period to the customers under two circumstances: 1) when delay period is less than the cycle of time;and 2) when delay period is greater than the cycle of time. The method is suitable for the items like state-of-the-art aircrafts, super computers, laptops, android mobiles, seasonal items and machines and their spare parts. A solution procedure algorithm is given for finding the optimal order quantity which minimizes the total cost of an inventory system. The article includes numerical examples to support the effectiveness of the developed model. Finally, sensitivity analysis on some parameters on optimal solution is provided. 展开更多
关键词 Constant Deterioration RATE Deteriorating Items Economic Order Quantity permissible Delay in PAYMENT SALVAGE Value TIME-DEPENDENT QUADRATIC DEMAND RATE
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Studies on permissible levels of breathing resistance for aircraft oxygen equipment(Review)
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作者 马瑞山 《Journal of Medical Colleges of PLA(China)》 CAS 1994年第2期123-126,共4页
We have formulated 3 permissible levels of respiratory resistance for aircraft oxygen equipment in China based on a comprehensive analysis of the results of human pkysiological experiments and feasibility of technolog... We have formulated 3 permissible levels of respiratory resistance for aircraft oxygen equipment in China based on a comprehensive analysis of the results of human pkysiological experiments and feasibility of technological design and performance with reference to existing standards and data. The ideal level can be used as a basic human physiological criterion. The applied permissible level is a criterion that must be followed in the process of design and production. The permissible level during maximum flow rate is presented as an extended allowable criterion for possible exceeding of the stable level for a short time. 展开更多
关键词 AIRCRAFT OXYGEN EQUIPMENT added RESPIRATORY RESISTANCE RESISTANCE permissible level mask cavity pressure RESPIRATORY flow rate threshold for RESPIRATORY RESISTANCE SENSATION physical load
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An Inventory Model for Deteriorating Items under Conditionally Permissible Delay in Payments Depending on the Order Quantity
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作者 Sumana Bera Samarjit Kar +1 位作者 Tripti Chakraborti Bani Kumar Sinha 《Applied Mathematics》 2014年第17期2675-2695,共21页
The purpose of this inventory model is to investigate the retailer’s optimal replenishment policy under permissible delay in payments. In this paper, we assume that the supplier would offer the retailer partially per... The purpose of this inventory model is to investigate the retailer’s optimal replenishment policy under permissible delay in payments. In this paper, we assume that the supplier would offer the retailer partially permissible delay in payments when the order quantity is smaller than a predetermined quantity (W). The most inventory systems are usually formed without considering the effect of deterioration of items which deteriorate continuously like fresh fruits, vegetables etc. Here we consider the loss due to deterioration. In real world situation, the demand of some items varies with change of seasons and occasions. So it is more significant if the loss of deterioration is time dependent. Considering all these facts, this inventory model has been developed to make more realistic and flexible marketing policy to the retailer, also establish the result by ANOVA analysis by treating different model parameters as factors. 展开更多
关键词 INVENTORY ECONOMIC Order Quantity (EOQ) DETERIORATION permissible DELAY in PAYMENT Weibull Distribution
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Origin of Erosion and Hydraulic Problems of the San Roque Underground Arched Culvert Channel and Its Relationship with the Maximum Flow Rate and the Maximum Permissible Velocity
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作者 Martín Mundo-Molina Daniel Hernández-Cruz 《Journal of Water Resource and Protection》 2020年第12期1123-1139,共17页
This work presents the hydrologic estimations of the hydraulic underground arched culvert channel (UACC) in Sabinal Basin, Chiapas, México and the hydrological problems associated with it, such as the erosion phe... This work presents the hydrologic estimations of the hydraulic underground arched culvert channel (UACC) in Sabinal Basin, Chiapas, México and the hydrological problems associated with it, such as the erosion phenomenon and abrasion cavity formation in it. On the other hand, the maximum flows that the UACC could transport were analyzed, concluding that it no longer has the hydraulic capacity to transport the flow rate associated to return periods equal to or greater than five years and that maximum permissible velocity UACC’s bottom is 3 m/s. 展开更多
关键词 Collapse Underground Arched Culvert Channel Maximum Flow Rate Maximum permissible Water Velocity Open Channel Bottom Erosion
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Permissible Stress Level of Brick Masonry under Compressive Cyclic Loading
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作者 Milad Mahmoud Alshebani 《Journal of Civil Engineering and Architecture》 2013年第2期153-157,共5页
Laboratory tests revealed that the behavior of brick masonry under compressive cyclic loading is characterized by three distinct stress-strain curves. These three curves are termed as envelope curve, common point curv... Laboratory tests revealed that the behavior of brick masonry under compressive cyclic loading is characterized by three distinct stress-strain curves. These three curves are termed as envelope curve, common point curve and stability point curve. The envelope curve is obtained by superimposing the cyclic peaks on the monotonic stress-strain curve. The common point curve is the locus of intersection points of loading and unloading curves of the cycles. If for the same cycle, the loading and unloading are repeated several times, the intersection points of loading and unloading paths will stabilize at a lower bound. The locus of these stabilized points (lower bound points) of all cycles form the stability point curve. Therefore, the stability point curve can be used as a measure for the allowable stress for masonry under cyclic loadings. The proposed cyclic allowable stress level is associated with the accumulation of residual (plastic) strain levels as a result of cyclic loading history. The permissible stress level was found to be about two thirds of the cyclic peak stress of the specimen. 展开更多
关键词 Cyclic loadings permissible stress residual strain stability point.
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The Legally Permissible Traditional Customary Uses of Wildlife and Forests under Kenyan Law
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作者 Nixon Sifuna 《Open Journal of Forestry》 2021年第3期292-314,共23页
Kenya like most of sub-Saharan Africa is reliant predominantly on agriculture and natural resources;which include land, water, minerals and fisheries, but the most dominant of which are wildlife and forestry. Unlike m... Kenya like most of sub-Saharan Africa is reliant predominantly on agriculture and natural resources;which include land, water, minerals and fisheries, but the most dominant of which are wildlife and forestry. Unlike minerals which are by law vested in the government and can only be extracted by it and not the citizenry, wildlife and forestry are resources that the citizens may utilize in their day to day lives to meet their needs. Apart from their consumptive uses, there are also non-consumptive uses and values of wild animals and forests;such as their intrinsic ecological value as gene banks, as well as their scenic value for viewing. These are essentially conventional values and uses. They are largely formal and universal ones that are universally obtaining across the world irrespective of the levels of civilization or cultural identity, and are even compatible with modernity. Apart from these, there are some wildlife and forestry uses which are unique to the typical African way of life as part of old traditional customs that have existed from earlier times. These are what are in this paper referred to as “traditional customary uses”. These uses are largely informal, rudimentary and archaic. They are nevertheless critical in the endemic African way of life and represent the inextricable rudimentary technologically bereft relationship between the African people and their natural resources. Under the country’s existing laws, some of these uses are prohibited and criminal sanctions prescribed to enforce their proscription, hence cannot be enjoyed or practiced. There are however others that the law has either expressly allowed, or not prohibited, hence may be lawfully enjoyed or practiced. These are what this paper has referred to as the legally permissible traditional customary uses;and are the ones that are its subject. As for wildlife, in the year 1977, the Kenya Government by a Legal Notice in the Kenya Gazette imposed a ban on all forms of hunting of wildlife. The ban is still in force. This therefore means that hunting is illegal, as legal prohibition has in effect prohibited all and any form of off-take or killing of wildlife. By implication therefore, under Kenyan law, only non-consumptive uses of wildlife may be enjoyed, and not the consumptive ones. These include viewing as well as socio-cultural and spiritual uses. In Kenya therefore, the only permissible traditional customary use of wildlife is its non-consumptive use for socio-cultural and spiritual purposes;subject of course to the existing legal prohibition on witchcraft under the Witchcraft Act <span style="color:#943634;">(<a href="#ref53">Cap 67 Laws of Kenya<a href="file:///C:/Users/test.scirp/Desktop/%E6%96%B0%E5%BB%BA%20Microsoft%20Word%20%E6%96%87%E6%A1%A3.docx#R53">). This piece of legislation has prohibited the practice and promotion of witchcraft. This in effect means that the socio-cultural and spiritual uses of wildlife though legally permissible, will be enjoyed, provided it is not for witchcraft purposes. With regard to forests, this author has identified the following five as their legally permissible traditional customary uses under Kenyan law: Socio-cultural and spiritual (consumptive and non-consumptive) use, other than for witchcraft;use in herbal folk medicine, other than for witchcraft;use for human food and livestock fodder;use for firewood;and use as raw material in construction and traditional craft. Notably, in Kenya, traditional customary use is subject to the existing legal prohibition on witchcraft. Further, while it is the legally permissible use category that is the focus of this paper, the author nevertheless discusses the prohibited traditional customary uses as well. This paper is based on literature survey as well as data obtained from the author’s previous research whose primary data and findings have been published in recent times. It also draws from the documented research and diverse documented views of other commentators on the subject. 展开更多
关键词 Traditional Customary Uses Legally permissible WILDLIFE FORESTS WITCHCRAFT Witchcraft Act Kenyan Law Taina
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Permissive hypercapnia combined with goal-directed fluid therapy improve postoperative mental health in elderly patients undergoing laparoscopic surgery
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作者 Li Yuan Xiao-Min Zhang +4 位作者 Na Liu Jun-Qi Shi Xiao-Jie Sun Guo-Li Li Jin-Liang Teng 《World Journal of Psychiatry》 2025年第7期145-155,共11页
BACKGROUND An investigation is undertaken to assess the effects of permissive hypercapnia(PH)combined with goal-directed fluid therapy(GDFT)on postoperative recovery and psychological well-being among elderly patients... BACKGROUND An investigation is undertaken to assess the effects of permissive hypercapnia(PH)combined with goal-directed fluid therapy(GDFT)on postoperative recovery and psychological well-being among elderly patients undergoing laparoscopic surgical procedures.AIM To ascertain whether the combination of PH and GDFT improves clinical recovery indicators,reduces postoperative complications,and alleviates anxiety,depression,and inflammatory responses in this specific patient population.METHODS A total of 120 elderly patients who underwent laparoscopic surgery in our hospital from July 2023 to June 2024 were randomly allocated into two groups:A control group(n=60)and a study group(n=60).In the control group,conventional anesthesia ventilation and fluid management protocols were administered,while in the study group,PH(with intraoperative PaCO_(2) maintained between 45-55 mmHg)was combined with GDFT.Postoperative recovery indicators,including the time to first flatus,time to ambulation,and length of hospital stay,were compared between the groups.Additionally,complication rates,anxietydepression scores assessed via the Hospital Anxiety and Depression scale,and levels of inflammatory factors were analyzed to evaluate the outcomes.RESULTS When compared with the control group,the study group demonstrated significantly shorter time to first flatus[(48.3±6.2)hours vs(62.5±7.8)hours],time to ambulation[(28.4±4.2)hours vs(38.6±5.1)hours],and length of hospital stay[(5.2±1.1)days vs(7.4±1.3)days](P<0.05).A significantly lower postoperative complication rate was observed in the study group(8.3%vs 21.7%,P<0.05).Additionally,at 3 days postoperatively,significantly lower anxiety scores[(5.2±1.4)vs(7.8±1.6)]and depression scores[(4.8±1.2)vs(7.1±1.5)]were recorded in the study group compared to the control group(P<0.05);Furthermore,at 24 hours postoperatively,serum levels of interleukin-6,tumor necrosis factorα,and C-reactive protein were found to be significantly lower in the study group than in the control group(P<0.05).CONCLUSION Postoperative recovery is significantly expedited,postoperative complications are markedly reduced,anxietydepression status is substantially improved,and inflammatory response is notably diminished in elderly patients undergoing laparoscopic surgery when PH is combined with GDFT,thereby making it worthy of clinical application. 展开更多
关键词 Permissive hypercapnia Goal-directed fluid therapy Laparoscopic surgery Elderly patients Enhanced recovery Anxiety and depression
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On the Evils of Torture and Its Permissibility:A Discussion Centered on Kramer’s View of Torture
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作者 ZHANG Zhucheng PAN Yingzhao(Translated) 《The Journal of Human Rights》 2025年第1期209-233,共25页
In the legal and philosophical study of torture,two major problems arise:Why is torture evil(Problem 1)?And is there a form of permissible torture(Problem 2)?The key issue in Problem 1 is demonstrating the uniqueness ... In the legal and philosophical study of torture,two major problems arise:Why is torture evil(Problem 1)?And is there a form of permissible torture(Problem 2)?The key issue in Problem 1 is demonstrating the uniqueness of the evils of torture,while Problem 2 aims to find a suitable theory to balance the“intuitive rejection”and“intuition of exceptional cases”in the ticking bomb scenario.Existing mainstream approaches have generally failed to resolve these issues.However,Matthew Kramer’s view of torture addresses both aspects of these problems.For Problem 1,Kramer adopts a perpetrator-centered viewpoint,arguing that torture undermines the moral integrity of the perpetrator.Regarding Problem 2,he suggests that the situation we face is a moral conflict in which the use of torture is morally wrong but might be the best action in a given context,granting it a weaker form of permissibility.However,in terms of the evils of torture,Kramer fails to explain its uniqueness.His theory cannot apply to all types of torture,and his perpetrator-centered argument contains logical flaws.Regarding the permissibility of torture,while Kramer’s overall approach is correct,he does not provide a reasonable explanation of the moral obligation to“forbid torture”or the prima facie surrounding it.A correct view of torture should adhere to an inmate-centered viewpoint,understanding the evils of torture in an additive manner in Problem 1,and acknowledging the existence of moral conflict in Problem 2.It should not only demonstrate that,in some situations,the use of torture may be the morally best option,but also show that the moral obligation to prohibit torture is simply outweighed under these circumstances. 展开更多
关键词 TORTURE inquisition by torture Matthew Kramer evil of torture permissibility of torture
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SecureVFL: Privacy-preserving multi-party vertical federated learning based on blockchain and RSS
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作者 Mochan Fan Zhipeng Zhang +4 位作者 Zonghang Li Gang Sun Hongfang Yu Jiawen Kang Mohsen Guizani 《Digital Communications and Networks》 2025年第3期837-849,共13页
Vertical Federated Learning(VFL),which draws attention because of its ability to evaluate individuals based on features spread across multiple institutions,encounters numerous privacy and security threats.Existing sol... Vertical Federated Learning(VFL),which draws attention because of its ability to evaluate individuals based on features spread across multiple institutions,encounters numerous privacy and security threats.Existing solutions often suffer from centralized architectures,and exorbitant costs.To mitigate these issues,in this paper,we propose SecureVFL,a decentralized multi-party VFL scheme designed to enhance efficiency and trustworthiness while guaranteeing privacy.SecureVFL uses a permissioned blockchain and introduces a novel consensus algorithm,Proof of Feature Sharing(PoFS),to facilitate decentralized,trustworthy,and high-throughput federated training.SecureVFL introduces a verifiable and lightweight three-party Replicated Secret Sharing(RSS)protocol for feature intersection summation among overlapping users.Furthermore,we propose a(_(2)^(4))-sharing protocol to achieve federated training in a four-party VFL setting.This protocol involves only addition operations and exhibits robustness.SecureVFL not only enables anonymous interactions among participants but also safeguards their real identities,and provides mechanisms to unmask these identities when malicious activities are performed.We illustrate the proposed mechanism through a case study on VFL across four banks.Finally,our theoretical analysis proves the security of SecureVFL.Experiments demonstrated that SecureVFL outperformed existing multi-party VFL privacy-preserving schemes,such as MP-FedXGB,in terms of both overhead and model performance. 展开更多
关键词 Permissioned blockchain Vertical federated learning Privacy protection Replicated secret sharing
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Corrigendum regarding previously published articles
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《Data Science and Management》 2025年第1期116-116,共1页
The editors regret that the following statements were missing in the published version for the following articles that appeared in previous issues of Data Science and Management:1.“Audiovisual speech recognition base... The editors regret that the following statements were missing in the published version for the following articles that appeared in previous issues of Data Science and Management:1.“Audiovisual speech recognition based on a deep convolutional neural network”(Data Science and Management,2024,7(1):25–34).https://doi.org/10.1016/j.dsm.2023.10.002.Ethics statement:The authors declare the Institutional Ethics Committee confirmed that no ethical review was required for this study.The authors have taken the participants’permission and consent to participate in this study. 展开更多
关键词 deep convolutional neural network data data science participant permission ethical review audiovisual speech recognition ethics statement deep convolutional neural network institutional ethics committee
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A Note on a One-Parameter Weibull Distributed Deteriorating Item EOQ Inventory Model with Varying Quadratic Demand and Delay in Payments
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作者 Trailokyanath Singh Itishree Rout Ameeya Kumar Nayak 《American Journal of Operations Research》 2024年第5期151-167,共17页
In this paper, an EOQ inventory model is developed for deteriorating items with variable rates of deterioration and conditions of grace periods when demand is a quadratic function of time. The deterioration rate consi... In this paper, an EOQ inventory model is developed for deteriorating items with variable rates of deterioration and conditions of grace periods when demand is a quadratic function of time. The deterioration rate considered here is a special type of Weibull distribution deterioration rate, i.e., a one-parameter Weibull distribution deterioration rate and it increases with respect to time. The quadratic demand precisely depicts of the demand of seasonal items, fashion apparels, cosmetics, and newly launched essential commodities like android mobiles, laptops, automobiles etc., coming to the market. The model is divided into three policies according to the occurrence of the grace periods. Shortages, backlogging and complete backlogging cases are not allowed to occur in the model. The proposed model is well-explained with the help of a simple solution procedure. The three numerical examples are taken to illustrate the effectiveness of the EOQ inventory model along with sensitivity analysis. 展开更多
关键词 Economic Order Quantity (EOQ) One-Parameter Weibull Distribution Deterioration permissible Delay in Payments Time-Dependent Quadratic Demand
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Covalent Bond Based Android Malware Detection Using Permission and System Call Pairs
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作者 Rahul Gupta Kapil Sharma R.K.Garg 《Computers, Materials & Continua》 SCIE EI 2024年第3期4283-4301,共19页
The prevalence of smartphones is deeply embedded in modern society,impacting various aspects of our lives.Their versatility and functionalities have fundamentally changed how we communicate,work,seek entertainment,and... The prevalence of smartphones is deeply embedded in modern society,impacting various aspects of our lives.Their versatility and functionalities have fundamentally changed how we communicate,work,seek entertainment,and access information.Among the many smartphones available,those operating on the Android platform dominate,being the most widely used type.This widespread adoption of the Android OS has significantly contributed to increased malware attacks targeting the Android ecosystem in recent years.Therefore,there is an urgent need to develop new methods for detecting Android malware.The literature contains numerous works related to Android malware detection.As far as our understanding extends,we are the first ones to identify dangerous combinations of permissions and system calls to uncover malicious behavior in Android applications.We introduce a novel methodology that pairs permissions and system calls to distinguish between benign and malicious samples.This approach combines the advantages of static and dynamic analysis,offering a more comprehensive understanding of an application’s behavior.We establish covalent bonds between permissions and system calls to assess their combined impact.We introduce a novel technique to determine these pairs’Covalent Bond Strength Score.Each pair is assigned two scores,one for malicious behavior and another for benign behavior.These scores serve as the basis for classifying applications as benign or malicious.By correlating permissions with system calls,the study enables a detailed examination of how an app utilizes its requested permissions,aiding in differentiating legitimate and potentially harmful actions.This comprehensive analysis provides a robust framework for Android malware detection,marking a significant contribution to the field.The results of our experiments demonstrate a remarkable overall accuracy of 97.5%,surpassing various state-of-the-art detection techniques proposed in the current literature. 展开更多
关键词 ANDROID MALWARE android security hybrid analysis permission and system call pairs
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Android Permission机制的实现与安全分析 被引量:6
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作者 张中文 雷灵光 王跃武 《信息网络安全》 2012年第8期3-6,共4页
Permission机制作为Android安全的重要组成部分,受到了越来越多的关注,已有的研究主要集中在对应用程序申请的Permission进行静态分析上。文章从分析Permission机制的实现过程入手,分析了Permission机制自身的安全问题,发现了一个Permis... Permission机制作为Android安全的重要组成部分,受到了越来越多的关注,已有的研究主要集中在对应用程序申请的Permission进行静态分析上。文章从分析Permission机制的实现过程入手,分析了Permission机制自身的安全问题,发现了一个Permission机制漏洞。应用程序利用该漏洞可以绕过权限管理,主动提升应用程序的访问权限,为后续攻击提供支持。同时文章也对Permission机制其它方面的安全特性进行了分析。 展开更多
关键词 ANDROID系统 PERMISSION 安全 漏洞
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POLLUTION TREND IN THE TUMEN RIVER AND ITS INFLUENCE ON REGIONAL DEVELOPMENT 被引量:2
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作者 田卫 俞穆清 +1 位作者 王国平 郭传新 《Chinese Geographical Science》 SCIE CSCD 1999年第2期50-54,共5页
The Tumen River had failed to meet Grade Ⅲ and Ⅳ levels in the environmental quality standard for surface water, and had exceeded Grade Ⅴ level. Surface water pollution is serious. The major excessive standard poll... The Tumen River had failed to meet Grade Ⅲ and Ⅳ levels in the environmental quality standard for surface water, and had exceeded Grade Ⅴ level. Surface water pollution is serious. The major excessive standard pollutants were COD Mn and SS. After taking effective treatment steps, the worsening trend of water pollution will be basically under control. But the change of runoff in the Tumen River is large in a year, especially during as long as five month freezing period, smaller flow and lower temperature of river waters led to weak dilution and self purification capacity. The water quality of the Tumen River will not reach the appoint functional water quality standards, even if sewage meets discharge standard, which will influence water resources utilization in the lower reaches of the Tumen River and regional economic development. Therefore water pollution has become the major restrictive factor of the development of the Tumen River area. 展开更多
关键词 water POLLUTION environmental capacity permissible AMOUNT of WASTEWATER DISCHARGE the Tumen RIVER
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一种增强的Android安全机制模型 被引量:9
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作者 陈伟鹤 邱道龙 《无线通信技术》 2014年第1期37-41,共5页
随着Android系统的日益流行,其安全问题受到了越来越多的关注。尽管Android Permission机制能在一定程度上保证安全性,但在实际应用中却缺乏灵活性,基于此提出了一种与Apex相兼容的策略模型。该方法主要针对Apex的安装程序包Poly。在Plo... 随着Android系统的日益流行,其安全问题受到了越来越多的关注。尽管Android Permission机制能在一定程度上保证安全性,但在实际应用中却缺乏灵活性,基于此提出了一种与Apex相兼容的策略模型。该方法主要针对Apex的安装程序包Poly。在Ploy安装程序之前先对应用程序和权限进行分析检测,然后将检测分析后的权限呈现给用户。实验结果表明在造成一定性能损失的情况下,新的框架可以有效减少用户所需设置的权限。 展开更多
关键词 ANDROID ANDROID PERMISSION 安全 策略模型
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Irrigation erosion of irrigated soils in the foothills of southern Kazakhstan 被引量:1
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作者 Abdulla S SAPAROV Enadiy K МIRZAKEEV +2 位作者 Tatyana M SHARYPOVA Galymzhan A SAPAROV Jilili ABUDUWAILI 《Journal of Arid Land》 SCIE CSCD 2013年第2期166-171,共6页
Abstract: This paper presented the results from the study of irrigation erosion of irrigated lands in southern Ka- zakhstan. The main purpose of the work is the conservation of the fertility of irrigated soils, and t... Abstract: This paper presented the results from the study of irrigation erosion of irrigated lands in southern Ka- zakhstan. The main purpose of the work is the conservation of the fertility of irrigated soils, and then the soils of the upper, middle and lower sections of the slopes at the experimental site were studied. Based on field investigations, authors studied the water resistance of aggregates of gray-brown soils and light gray soils before and after irrigation and qualitative indicators of changes in physical and chemical properties of structured soils in irrigation were de- termined by conventional methods of soil research. The results indicated that the changes in the physical properties of soils by using polymeric compounds created a fundamentally new opportunity to control water erosion of soils. 展开更多
关键词 irrigation erosion furrow irrigation structure-forming polymers deformation of furrows permissible water speed aggregate water stability
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Defluoridation of Water by a Biomass: <i>Tinospora cordifolia</i> 被引量:1
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作者 Piyush Kant Pandey Madhurima Pandey Rekha Sharma 《Journal of Environmental Protection》 2012年第7期610-616,共7页
This research is focused on the search of a biomass for the sequestration of fluoride from drinking water. Defluoridation of water was studied by batch experiments in biosorption process. The biomass was found to redu... This research is focused on the search of a biomass for the sequestration of fluoride from drinking water. Defluoridation of water was studied by batch experiments in biosorption process. The biomass was found to reduce fluoride to permissible limit 1.5 mg/L as prescribed by WHO. The efficiency of the sorption process was investigated under different experimental parameters such as pH 7, standing time 120 min and biomass doses 7.0 g with 5 mg/L concentration of fluoride. Neutral pH was identified as the optimum condition of the medium and 120 minutes was the best contact time for maximum fluoride adsorption. The experimental data was found good fitting to Langmuir and Freundlich isotherm models. In interference study tolerable effect was found with 50 mg/L concentration of co-ions, whereas increasing the concentration of co-ions retarded the fluoride removal capacity in some extent. FT-IR spectrum analysis showed fluoride binding in the different frequency ranges of the biomass. Eventually, this plant biomass is recommended as a suitable and low cost adsorbent to reduce fluoride into standard permissible limit. 展开更多
关键词 SEQUESTRATION DEFLUORIDATION BIOSORPTION FT-IR Spectrum permissible
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Android操作系统的安全机制研究 被引量:2
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作者 朱长江 杨一平 《电脑知识与技术》 2013年第9期5628-5629,共2页
Android系统自推出以来,就以明显的优势逐渐扩大市场占有份额。Android是一个开放性的系统,备受开发者的青睐,其安全性至关重要。研究了Android系统的用户ID机制、应用程序签名机制、沙箱隔离机制等安全策略,分析了它在硬件方面、Li... Android系统自推出以来,就以明显的优势逐渐扩大市场占有份额。Android是一个开放性的系统,备受开发者的青睐,其安全性至关重要。研究了Android系统的用户ID机制、应用程序签名机制、沙箱隔离机制等安全策略,分析了它在硬件方面、Linux内核方面及Android自身权限机制方面存在的安全隐患。 展开更多
关键词 ANDROID 安全机制 PERMISSION
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