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Cyberattack Ramifications, The Hidden Cost of a Security Breach
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作者 Meysam Tahmasebi 《Journal of Information Security》 2024年第2期87-105,共19页
In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term ... In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term consequences that businesses encounter. This study integrates findings from various research, including quantitative reports, drawing upon real-world incidents faced by both small and large enterprises. This investigation emphasizes the profound intangible costs, such as trade name devaluation and potential damage to brand reputation, which can persist long after the breach. By collating insights from industry experts and a myriad of research, the study provides a comprehensive perspective on the profound, multi-dimensional impacts of cybersecurity incidents. The overarching aim is to underscore the often-underestimated scope and depth of these breaches, emphasizing the entire timeline post-incident and the urgent need for fortified preventative and reactive measures in the digital domain. 展开更多
关键词 Artificial Intelligence (AI) Business Continuity Case Studies Copyright Cost-Benefit Analysis Credit Rating Cyberwarfare Cybersecurity Breaches Data Breaches Denial Of Service (DOS) Devaluation Of Trade Name Disaster Recovery Distributed Denial of Service (DDOS) Identity Theft Increased Cost to Raise Debt Insurance Premium Intellectual Property operational Disruption Patent Post-Breach Customer Protection Recovery Point Objective (RPO) Recovery Time Objective (RTO) Regulatory Compliance Risk Assessment Service Level Agreement Stuxnet Trade Secret
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A retrospective view on the history of natural sciences in XX-XXI
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作者 Vladislav Sergeyevich Olkhovsky 《Natural Science》 2010年第3期228-245,共18页
The presented paper is dedicated to a new ret-rospective view on the history of natural sci-ences in XX-XXI cc, partially including the sci-ence philosophy (mainly, the problems of the scientific realism, i.e. the cor... The presented paper is dedicated to a new ret-rospective view on the history of natural sci-ences in XX-XXI cc, partially including the sci-ence philosophy (mainly, the problems of the scientific realism, i.e. the correspondence of science to reality) and also a novel scheme for different classes of sciences with different ob-jects and paradigms. There are analyzed the chosen “great” and “grand” problems of phys-ics (including the comprehension of quantum mechanics, with a recently elaborated new chapter, connected with time as a quantum obs- ervable and time analysis of quantum processes) and also of natural sciences as a whole. The particular attention is paid to the interpretation questions and slightly to the aspects, inevitably connected with the world- views of the res- earchers (which do often constitute a part of the interpretation questions). 展开更多
关键词 SCIENCE history SCIENCE realism paradigm PROBLEM of interpretation and comprehension of QUANTUM mechanics the WAVE-FUNCTION collapse the Einstein-Podolsky-Rosen paradox TIME as a QUANTUM observable canonically conjugated to energy maximal hermitian TIME operator TIME analysis of QUANTUM processes relationship be-tween physics and biology PROBLEM of origin of biologic life REDUCTIONISM cosmologic PROBLEM Big Bang anthropic principle
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The Origins of Bosons and Fermions
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作者 ShaoXu Ren 《Journal of Modern Physics》 2014年第17期1848-1879,共32页
This paper proposes that all Bosons and all Fermions originate from even more elementary constituents, which called Spin Angular Momentum Vacuum (SAMV). SAMV is filled with Primitive Spin Particles (PSP). The total sq... This paper proposes that all Bosons and all Fermions originate from even more elementary constituents, which called Spin Angular Momentum Vacuum (SAMV). SAMV is filled with Primitive Spin Particles (PSP). The total square spin angular momentum of each PSP is negative, less than zero. Those PSP labeled by index ?of Casimir Operator, are called Vacuum Spin Particle (VSP), which could be contracted into so-called Vacuum Bubbles (VB). VB are identical bubbles, are 'sub-observable physical quantities'. VB are paired up into Vacuum Bubble Pair VBP. VSP ωj(or ω+,ω-) results from Self-identical vacuum bubble interaction ?through the zero order Phase Transition PT. When the 1st, 2nd, 3rd,... order PT of VBP occur, ?then VBP turn into Bosons and Fermions, excited out of sea level of SAMV ocean. 展开更多
关键词 SPIN Angular Momentum VACUUM SAMV Primitive SPIN PARTICLES PSP VACUUM SPIN PARTICLES VSP Abnormal Casimir Operator ACO VACUUM CONTRACTIONS VC VACUUM Bubbles VB VACUUM Bubble Pair VBP Phase Transitions PT BOSONS FERMIONS The Third Kind Of PARTICLES TKP Chaos SPIN Hierarchy CSH The Equivalence of VACUUM Bubbles Locality and Nonlocality of VACUUM CONTRACTIONS Local and Nonlocal Angular Momentum Commutations
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Research on the Optimization Design of Intersections for Safe Operation of Large Trucks
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作者 Yujie Bao Pincheng Wang Yuhang Li 《Journal of Information Hiding and Privacy Protection》 2020年第3期143-154,共12页
When big trucks are running at urban road intersections,they are easy to interfere with other motor vehicles,and the turning big trucks are easy to have conflicts with non-motor vehicles and pedestrians,which will aff... When big trucks are running at urban road intersections,they are easy to interfere with other motor vehicles,and the turning big trucks are easy to have conflicts with non-motor vehicles and pedestrians,which will affect the safety of intersections.This paper first studied the intersection of trucks to the running trajectory,on this basis,through the establishment of mathematical model analysis of large truck steering conditions inside the wheel,and the influence of blind area to the driver.In the research of intersection safety design,the safety design is divided into three parts:Entrance road,internal operation and signal control.At the same time,the design method of the entrance road,the interior of the intersection and the signal control is given,which improves the safety of the truck driving at the intersection.Finally,the intersection of Jungong road and Zhoujiazui road in Yangpu district of Shanghai was selected as a case,and the optimal design of the intersection for large trucks was carried out through the investigation and analysis of actual data.The evaluation and analysis were carried out by using the multi-index matter-element model.The results show that the comprehensive safety correlation degree of the intersection is reduced to 0.42,and the safety level of is improved by one level. 展开更多
关键词 Large truck city road intersection safety design safety operation inner wheel difference blind area
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RECIPROCALLY TOPOGRAPHIC PROJECTIONS BETWEEN THE OPTIC TECTUM AND NUCLEUS ISTHMI IN THE TOAD 被引量:1
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作者 王荫亭 颜坤 王书荣 《Chinese Science Bulletin》 SCIE EI CAS 1983年第1期139-140,共2页
关键词 In this letter neuronal projections BETWEEN the TOAD (Bufo BUFO gargarizans) optic toctum and nucleus isthmi (NI) are studied by means of horseradish peroxidase (HRP) method and HRP-labeled tectal and isthmic cells are classified.After surgical operation the animal was fixed in a stereotaxic apparatus. HRP (Sigma VI) was iontophorezed into different sites over superficial layers of the tectum in 53 TOADS and throughout NI in 13 TOADS one injection each animal. After their survival of 28 days at 1620 using HRP histochemical method the injected and labeled sites as well as the morphology of the labeled cells were shown.The results indicate that reciprocally topographic projections exist BETWEEN the TOAD optictectum and its ipsilateral NI i. e. an isthmic
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Higher Variations of the Monty Hall Problem (3.0, 4.0) and Empirical Definition of the Phenomenon of Mathematics, in Boole’s Footsteps, as Something the Brain Does 被引量:1
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作者 Leo Depuydt Richard D. Gill 《Advances in Pure Mathematics》 2012年第4期243-273,共31页
In Advances in Pure Mathematics (www.scirp.org/journal/apm), Vol. 1, No. 4 (July 2011), pp. 136-154, the mathematical structure of the much discussed problem of probability known as the Monty Hall problem was mapped i... In Advances in Pure Mathematics (www.scirp.org/journal/apm), Vol. 1, No. 4 (July 2011), pp. 136-154, the mathematical structure of the much discussed problem of probability known as the Monty Hall problem was mapped in detail. It is styled here as Monty Hall 1.0. The proposed analysis was then generalized to related cases involving any number of doors (d), cars (c), and opened doors (o) (Monty Hall 2.0) and 1 specific case involving more than 1 picked door (p) (Monty Hall 3.0). In cognitive terms, this analysis was interpreted in function of the presumed digital nature of rational thought and language. In the present paper, Monty Hall 1.0 and 2.0 are briefly reviewed (§§2-3). Additional generalizations of the problem are then presented in §§4-7. They concern expansions of the problem to the following items: (1) to any number of picked doors, with p denoting the number of doors initially picked and q the number of doors picked when switching doors after doors have been opened to reveal goats (Monty Hall 3.0;see §4);(3) to the precise conditions under which one’s chances increase or decrease in instances of Monty Hall 3.0 (Monty Hall 3.2;see §6);and (4) to any number of switches of doors (s) (Monty Hall 4.0;see §7). The afore-mentioned article in APM, Vol. 1, No. 4 may serve as a useful introduction to the analysis of the higher variations of the Monty Hall problem offered in the present article. The body of the article is by Leo Depuydt. An appendix by Richard D. Gill (see §8) provides additional context by building a bridge to modern probability theory in its conventional notation and by pointing to the benefits of certain interesting and relevant tools of computation now available on the Internet. The cognitive component of the earlier investigation is extended in §9 by reflections on the foundations of mathematics. It will be proposed, in the footsteps of George Boole, that the phenomenon of mathematics needs to be defined in empirical terms as something that happens to the brain or something that the brain does. It is generally assumed that mathematics is a property of nature or reality or whatever one may call it. There is not the slightest intention in this paper to falsify this assumption because it cannot be falsified, just as it cannot be empirically or positively proven. But there is no way that this assumption can be a factual observation. It can be no more than an altogether reasonable, yet fully secondary, inference derived mainly from the fact that mathematics appears to work, even if some may deem the fact of this match to constitute proof. On the deepest empirical level, mathematics can only be directly observed and therefore directly analyzed as an activity of the brain. The study of mathematics therefore becomes an essential part of the study of cognition and human intelligence. The reflections on mathematics as a phenomenon offered in the present article will serve as a prelude to planned articles on how to redefine the foundations of probability as one type of mathematics in cognitive fashion and on how exactly Boole’s theory of probability subsumes, supersedes, and completes classical probability theory. §§2-7 combined, on the one hand, and §9, on the other hand, are both self-sufficient units and can be read independently from one another. The ultimate design of the larger project of which this paper is part remains the increase of digitalization of the analysis of rational thought and language, that is, of (rational, not emotional) human intelligence. To reach out to other disciplines, an effort is made to describe the mathematics more explicitly than is usual. 展开更多
关键词 Artificial INTELLIGENCE Binary Structure BOOLEAN ALGEBRA BOOLEAN Operators Booles ALGEBRA Brain Science Cognition Cognitive Science DEFINITION of MATHEMATICS DEFINITION of Probability Theory Digital MATHEMATICS Electrical Engineering Foundations of MATHEMATICS Human INTELLIGENCE Linguistics Logic Monty HALL Problem Neuroscience Non-quantitative and Quantitative MATHEMATICS Probability Theory Rational Thought and Language
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A Methodology to Assess the Safety of Aircraft Operations When Aerodrome Obstacle Standards Cannot Be Met 被引量:9
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作者 Hartmut Fricke Christoph Thiel 《Open Journal of Applied Sciences》 2015年第2期62-81,共20页
When Aerodrome Obstacle Standards cannot be met as a result of urban or technical development, an aeronautical study can be carried out with the permission of EASA, in conjunction with ICAO, to prove how aircrafts can... When Aerodrome Obstacle Standards cannot be met as a result of urban or technical development, an aeronautical study can be carried out with the permission of EASA, in conjunction with ICAO, to prove how aircrafts can achieve an equivalent level of safety. However currently, no detailed guidance for this procedure exists. This paper proposes such a safety assessment methodology in order to value obstacle clearance violations around airports. This method has already been applied to a safety case at Frankfurt Airport where a tower elevating 4 km out of threshold 25R severely violates obstacle limitation surfaces. The model data refers to a take-off and landing performance model (TLPM) computing precisely aircraft trajectories for both standard and engine out conditions at ground proximity. The generated tracks are used to estimate collision risk incrementally considering EASA/FAA, EU-OPS & ICAO clearance criteria. Normal operations are assessed with a probabilistic analysis of empirical take-off/landing track data generating the local actual navigation performance (ANP) on site. The ANP shows integration to collision risk for an aircraft with any obstacle. The obstacle is tested for clearance within a “5-step-plan” against all performance requirements for landing climb and take-off climb. The methodology thereby delivers a comprehensive risk picture: The presented safety case for Frankfurt Airport showed an equivalent safety level despite the violation of standards. The collision risk during both normal and degraded performance operations was still found to be within ICAO Collision Risk Model (CRM) limits, requiring only limited risk mitigation measures. The presented work should complement ICAO Doc 9774 Appendix 3. 展开更多
关键词 Aeronautical Study AIRCRAFT Performance OBSTACLE CLEARANCE COLLISION Risk Engine out operations
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Study on the Safety and Prevention Technology of Coal Mining under the River in Xingyuan Coal Mine
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作者 Abdoulaye Sylla Wenbing Guo 《Open Journal of Geology》 CAS 2024年第3期339-402,共64页
Coal mining-induced surface subsidence poses significant ecological and infrastructural challenges, necessitating a comprehensive study to ensure safe mining practices, particularly in underwater conditions. This proj... Coal mining-induced surface subsidence poses significant ecological and infrastructural challenges, necessitating a comprehensive study to ensure safe mining practices, particularly in underwater conditions. This project aims to address the extensive impact of coal mining on the environment, infrastructure, and overall safety, focusing on the Shigong River area above the working face. The study employs qualitative and quantitative analyses, along with on-site engineering measurements, to gather data on crucial parameters such as coal seam characteristics, roof rock lithology, thickness, water resistance, and structural damage degree. The research encompasses a multidisciplinary approach, involving mining, geology, hydrogeology, geophysical exploration, rock mechanics, mine surveying, and computational mathematics. The importance of effective safety measures and prevention techniques is emphasized, laying the foundation for research focused on the Xingyun coal mine. The brief concludes by highlighting the potential economic and social benefits of this project and its contribution to valuable experience for future subsea coal mining. 展开更多
关键词 Coal Mining-Induced Surface Subsidence Ecological and Infrastructural Challenges safe Mining Practices Underwater Conditions Multidisciplinary Approach safety Measures Prevention Techniques
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Application of the Regulations on Drawing of a Safe Firing Area Map in Weather Modification Operation 被引量:1
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作者 Wang Xiaoli Wang Tianru +3 位作者 Zhang Na Xu Tai’an Lu Dan Zhang Xiuzhen 《Meteorological and Environmental Research》 CAS 2017年第1期31-32,共2页
Technology for safe firing area maps was introduced firstly,and then potential danger after the launching of shells by an antiaircraft gun and a rocket was analyzed.Finally,problems in the process of applying the regu... Technology for safe firing area maps was introduced firstly,and then potential danger after the launching of shells by an antiaircraft gun and a rocket was analyzed.Finally,problems in the process of applying the regulations and their solutions were discussed.The application of safe firing area maps can provide technical support for the efficient development of weather modification operation. 展开更多
关键词 WEATHER modification operation safe FIRING area maps REGULATIONS APPLICATION China
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Implicit Shape Reconstruction of Unorganized Points Using PDE-Based Deformable 3D Manifolds 被引量:2
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作者 Elena Franchini Serena Morigi Fiorella Sgallari 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2010年第4期405-430,共26页
In this work we consider the problem of shape reconstruction from an unorganized data set which has many important applications in medical imaging, scientific computing, reverse engineering and geometric modelling. Th... In this work we consider the problem of shape reconstruction from an unorganized data set which has many important applications in medical imaging, scientific computing, reverse engineering and geometric modelling. The reconstructed surface is obtained by continuously deforming an initial surface following the Partial Differential Equation (PDE)-based diffusion model derived by a minimal volume-like variational formulation. The evolution is driven both by the distance from the data set and by the curvature analytically computed by it. The distance function is computed by implicit local interpolants defined in terms of radial basis functions. Space discretization of the PDE model is obtained by finite co-volume schemes and semi-implicit approach is used in time/scale. The use of a level set method for the numerical computation of the surface reconstruction allows us to handle complex geometry and even changing topology,without the need of user-interaction. Numerical examples demonstrate the ability of the proposed method to produce high quality reconstructions. Moreover, we show the effectiveness of the new approach to solve hole filling problems and Boolean operations between different data sets. 展开更多
关键词 Partial Differential Equation surface reconstruction numerical computation BOOLEAN operations distance function level SET method data SET complex geometry approach diffusion model effectiveness high quality different problems CHANGING used in medical initial defined PDE
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A cross-sectional study to assess medication safety,knowledge,attitude,and practices regarding nutrition and medication among pregnant women
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作者 Gauthami R Bipin Shaji +3 位作者 Twinkle MJS Krishnapriya Radhakrishnan Reshma Kolar Juno Jerold Joel 《Asian pacific Journal of Reproduction》 CAS 2024年第3期115-119,共5页
Objective:To assess pregnant women's knowledge,attitude,and practice regarding nutrition and medication usage,analyse the prescribing pattern,and categorize them based on the Food and Drug Administration(FDA)guide... Objective:To assess pregnant women's knowledge,attitude,and practice regarding nutrition and medication usage,analyse the prescribing pattern,and categorize them based on the Food and Drug Administration(FDA)guidelines.Methods:A cross-sectional study was conducted with 264 pregnant women in the obstetrics and gynaecology department of a tertiary care hospital from October 2022 to August 2023.A knowledge,attitude,and practice(KAP)questionnaire was prepared in English language by the researchers and validated by an expert panel consisting of 12 members.The validated questionnaire was then translated into regional languages,Kannada and Malayalam.The reliability of the questionnaire was assessed with test-retest method with a representative sample population of 30 subjects(10 subjects for each language).The subjects'knowledge,attitude,and practice were evaluated using the validated KAP questionnaire.The safety of the medication was assessed using the FDA drug safety classification for pregnancy.Results:The mean scores for nutritional and medication usage knowledge,attitude,and practice were 4.14±1.15,4.50±1.09,and 3.00±1.47,respectively.Among 30 prescribed medications,3 belong to category A(no risk in human studies),8 belong to category B(no risk in animal studies),18 belong to category C(risk cannot be ruled out)and 1 drug is not classified.A significant association was observed between medication knowledge and practice(r=0.159,P=0.010).Conclusions:Most of the study population knows the need to maintain good dietary and medication practices during pregnancy.Counselling pregnant women regarding diet and medication usage is crucial in maternal care. 展开更多
关键词 PREGNANCY NUTRITION MEDICATION KNOWLEDGE Practice safe medication
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Validation of a Questionnaire to Diagnose the Baumann Skin Type in All Ethnicities and in Various Geographic Locations
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作者 Leslie Baumann 《Journal of Cosmetics, Dermatological Sciences and Applications》 2016年第1期34-40,共7页
The Baumann Skin Typing System diagnoses patients as having one of 16 skin types based on their answers to a validated questionnaire [i] known as the Baumann Skin Type Indicator [ii]. The BSTI questionnaire has been t... The Baumann Skin Typing System diagnoses patients as having one of 16 skin types based on their answers to a validated questionnaire [i] known as the Baumann Skin Type Indicator [ii]. The BSTI questionnaire has been tested over the last decade on over 200,000 people of various ages and ethnicities in different geographic locations around the world. In this study, data were collected from 52,862 patients to compare skin type prevalence between those who presented to doctor’s offices and those who took the quiz without supervision online. The most common skin types varied only slightly between patients that took the quiz online and those that completed the questionnaire in their doctor’s office. This indicates that the prevalence of skin types seen in the doctor’s office is similar to that in the general population and that supervision is not necessary to get an accurate result on the BSTI. [iii] In addition, comparison of data gathered in China, Korea, and the US did not show a significant difference in skin type prevalence between Asian and Caucasian skin types. [iv] This study demonstrates that the English version of the BSTI is valid for English speaking patients online, and in doctors’ offices in the US, China and Korea. 展开更多
关键词 Skin Type Regimen COSMECEUTICAL Skin Care Oily Dry Sensitive Pigmented Wrinkled Photoaged MELASMA Pre-Operative Post-Operative Acne ROSACEA Contact Dermatitis Antioxidants Retinoids Baumann Skin Type BSTI Skin IQ Skin Type Solutions Systems-Based Approach Standardized Methodology Validated VALIDATION Scientific Ethnicity Asian Hispanic Caucasian QUESTIONNAIRE Diagnostic DIAGNOSE Prescribe Educate Outcomes Compliance
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Continuous wave and active Q-switched operation of Watt-level LED-pumped two-rod Nd,Ce:YAG laser
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作者 沈建平 芦鹏 +4 位作者 徐少聪 江容容 陈阳 陈亮 邢凤阳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期361-366,共6页
A high-performance LED-side-pumped two-rod Nd,Ce:YAG laser with continuous-wave(CW) and acousto–optical(A-O) Q-switched operation is demonstrated in this work. A symmetrically shaped flat–flat cavity with two identi... A high-performance LED-side-pumped two-rod Nd,Ce:YAG laser with continuous-wave(CW) and acousto–optical(A-O) Q-switched operation is demonstrated in this work. A symmetrically shaped flat–flat cavity with two identical LEDside-pumped laser modules is employed for power scalability. In the CW regime, the maximum output average power of laser at 1064 nm is 4.41 W, corresponding to a maximum optical conversion efficiency of 5.3% and a slope efficiency is 12.4%. In the active Q-switched regime, the pulse energy of laser reaches as high as 0.89 m J at a repetition rate of 800 Hz with a pulse width of 457.2 ns, the corresponding highest peak output power is 1.94 k W and the M~2 factor is measured to be about 8.8. To the best of the authors' knowledge, this is the first demonstration and the highest performance of a CW LED-side-pumped two-rod laser Nd,Ce:YAG with Watt-level output reported so far. 展开更多
关键词 Watt-level LED-pumped CW ND Ce:YAG actively Q-switched operation
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A Planning Method for Operational Test of UAV Swarm Based on Mission Reliability
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作者 Jingyu Wang Ping Jiang Jianjun Qi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1889-1918,共30页
The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV swarm.Due to the... The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV swarm.Due to the high cost and long duration of operational tests,it is essential to plan the test in advance.To solve the problem of planning UAV swarm operational test,this study considers the multi-stage feature of a UAV swarm mission,composed of launch,flight and combat stages,and proposes a method to find test plans that can maximize mission reliability.Therefore,a multi-stage mission reliability model for a UAV swarm is proposed to ensure successful implementation of the mission.A multi-objective integer optimization method that considers both mission reliability and cost is then formulated to obtain the optimal test plans.This study first constructs a mission reliability model for the UAV swarm in the combat stage.Then,the launch stage and flight stage are integrated to develop a complete PMS(Phased Mission Systems)reliability model.Finally,the Binary Decision Diagrams(BDD)and Multi Objective Quantum Particle Swarm Optimization(MOQPSO)methods are proposed to solve the model.The optimal plans considering both reliability and cost are obtained.The proposed model supports the planning of UAV swarm operational tests and represents a meaningful exploration of UAV swarm test planning. 展开更多
关键词 UAV swarm PMS MOQPSO BDD mission reliability operational test planning
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Effects of spot size on the operation mode of Ga As photoconductive semiconductor switch employing extrinsic photoconductivity
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作者 韦金红 李嵩 +5 位作者 陈红 曾凡正 贾成林 付泽斌 葛行军 钱宝良 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第5期91-99,共9页
To guide the illuminating design to improve the on-state performances of gallium arsenide(GaAs)photoconductive semiconductor switch(PCSS),the effect of spot size on the operation mode of GaAsPCSS based on a semi-insul... To guide the illuminating design to improve the on-state performances of gallium arsenide(GaAs)photoconductive semiconductor switch(PCSS),the effect of spot size on the operation mode of GaAsPCSS based on a semi-insulating wafer with a thickness of 1 mm,triggered by a 1064-nm extrinsic laser beam with the rectangular spot,has been investigated experimentally.It is found that the variation of the spot size in length and width can act on the different parts of the output waveform integrating the characteristics of the linear and nonlinear modes,and then significantly boosts the PCSS toward different operation modes.On this basis,a two-channel model containing the active and passive parts is introduced to interpret the relevant influencing mechanisms.Results indicate that the increased spot length can peak the amplitude of static domains in the active part to enhance the development of the nonlinear switching,while the extended spot width can change the distribution of photogenerated carriers on both parts to facilitate the linear switching and weaken the nonlinear switching,which have been proved by comparing the domain evolutions under different spot sizes. 展开更多
关键词 GaAs PCSS operation mode spot size on-state performances two-channel model domain evolution
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TRIANGLE operation,combined with adequate adjuvant chemotherapy,can improve the prognosis of pancreatic head cancer:A retrospective study
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作者 Jia-Hao Chen Li-Yong Zhu +7 位作者 Zhi-Wei Cai Xiao Hu Abousalam Abdoulkader Ahmed Jie-Qiong Ge Xiao-Yan Tang Chun-Jing Li Yun-Long Pu Chong-Yi Jiang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期1773-1786,共14页
BACKGROUND The TRIANGLE operation involves the removal of all tissues within the triangle bounded by the portal vein-superior mesenteric vein,celiac axis-common hepatic artery,and superior mesenteric artery to improve... BACKGROUND The TRIANGLE operation involves the removal of all tissues within the triangle bounded by the portal vein-superior mesenteric vein,celiac axis-common hepatic artery,and superior mesenteric artery to improve patient prognosis.Although previously promising in patients with locally advanced pancreatic ductal adenocarcinoma(PDAC),data are limited regarding the long-term oncological outcomes of the TRIANGLE operation among resectable PDAC patients undergoing pancreaticoduodenectomy(PD).AIM To evaluate the safety of the TRIANGLE operation during PD and the prognosis in patients with resectable PDAC.METHODS This retrospective cohort study included patients who underwent PD for pancreatic head cancer between January 2017 and April 2023,with or without the TRIANGLE operation.Patients were divided into the PD_(TRIANGLE)and PD_(non-TRIANGLE)groups.Surgical and survival outcomes were compared between the two groups.Adequate adjuvant chemotherapy was defined as adjuvant chemotherapy≥6 months.RESULTS The PD_(TRIANGLE)and PD_(non-TRIANGLE) groups included 52 and 55 patients,respectively.There were no significant differences in the baseline characteristics or perioperative indexes between the two groups.Furthermore,the recurrence rate was lower in the PD_(TRIANGLE) group than in the PD_(non-TRIANGLE) group(48.1%vs 81.8%,P<0.001),and the local recurrence rate of PDAC decreased from 37.8%to 16.0%.Multivariate Cox regression analysis revealed that PD_(TRIANGLE)(HR=0.424;95%CI:0.256-0.702;P=0.001),adequate adjuvant chemotherapy≥6 months(HR=0.370;95%CI:0.222-0.618;P<0.001)and margin status(HR=2.255;95%CI:1.252-4.064;P=0.007)were found to be independent factors for the recurrence rate.CONCLUSION The TRIANGLE operation is safe for PDAC patients undergoing PD.Moreover,it reduces the local recurrence rate of PDAC and may improve survival in patients who receive adequate adjuvant chemotherapy. 展开更多
关键词 TRIANGLE operation Pancreatic ductal adenocarcinoma Heidelberg triangle Adjuvant chemotherapy PROGNOSIS PANCREATICODUODENECTOMY
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The Safe Navigation of Partial Motion Planning Based on “Cooperation” with Roadside Fixed Sensors in VANET
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作者 Rong Ding Xiaoguang Li 《Wireless Sensor Network》 2010年第9期661-667,共7页
In recent years, many methods of safe vehicle navigation and partial motion planning (PMP) have been proposed in vehicular ad-hoc network (VANET) field. In order to improve the limitation of traditional PMP, this pape... In recent years, many methods of safe vehicle navigation and partial motion planning (PMP) have been proposed in vehicular ad-hoc network (VANET) field. In order to improve the limitation of traditional PMP, this paper presents a novel effective way to plan motion with cooperation of roadside fixed sensors (RFSs). With their cooperation, the vehicles can get the surrounding information quickly and effectively, and give highly accurate projections about the near future conditions on road. After proposing our algorithm, the worst case is analyzed and methods are found to solve the problem. Finally we conduct one elemental contrast experiment, driver situation awareness, with or without the “cooperation” of RFSs in highway scenarios. The result shows that the vehicles can make a better PMP based on the forward conditions received from RFSs, and extend the warning distance obviously when emergency happens. 展开更多
关键词 PARTIAL Motion Planning safe Vehicle Navigation ROADSIDE Fixed SENSORS COoperation
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Simulation of Diode-Pumped Q-Switched Nd:YAG Laser Generating Eye-Safe Signal in IOPO Environment
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作者 Mian M. Ashraf Muhammad Siddique 《Optics and Photonics Journal》 2012年第3期167-172,共6页
Numerical simulation of diode-pumped Q-switched Nd:YAG laser leading to the generation of eye-safe signal in singly resonant Intracavity Optical Parametric Oscillator (IOPO) is presented. Starting from rate equations,... Numerical simulation of diode-pumped Q-switched Nd:YAG laser leading to the generation of eye-safe signal in singly resonant Intracavity Optical Parametric Oscillator (IOPO) is presented. Starting from rate equations, the time dependent laser equations have been solved numerically, whereas the space-dependent OPO equations analytically. Our results show that 1.4 J diode laser (810 nm) pulse with 200 msec width, delivers 30 mJ Nd:YAG laser (1064 nm) pulse with 5 n-second width. This Nd:YAG laser further generates 9 mJ eye safe signal (1570 nm) pulse with 2.5 n-second width. 展开更多
关键词 SIMULATION Diode LASER Q-SWITCHED Nd:YAG LASER Eye-safe LASER SIGNAL Idler IOPO Rate Equations Out-Put Power KTP Non-Linear Crystal Pump Beam WAIST
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The Business of Managing Risk and Network Security:An Exploration of Knowledge Transfer Issues within the Context of Data Security and Countermeasure Trade Offs
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作者 Jim MorrisVice President(Trident Data Systems 12701 Fairlakes Circle.Suite 350 Fairfax,VA22033 USA)Jim SnaithPrincipal Lecturer In Business Information Systems(Area of Finance Accounting and Business Information SystemsSouth Bank University Business Schoo 《计算机工程》 CAS CSCD 北大核心 1996年第S1期68-81,共14页
The contemporary environment within which command,control,communications,computers and intelligence (C4I platforms exist, have a number of characteristics. These characteristics may be most obviously identified as int... The contemporary environment within which command,control,communications,computers and intelligence (C4I platforms exist, have a number of characteristics. These characteristics may be most obviously identified as interconnectivity, international networking, speed of data transfer, the compact nature of electronic information and rapidly changing technology. Information security professionals employ a variety of approaches in order to counter risks within this complex and fluid environment. The gamut of potential security activities ranges form access control through a variety of auditing techniques to secure data communications. This field is broad and well documented. Indeed, the discipline of network risk management and data security is both well developed and sophisticated.This paper addresses twin themes:i.The fundamental issue of the method by which specific approaches are employed. This is a precursor to the adoption of an eventual strategy.ii.The crucial issues revolving around the 展开更多
关键词 VALUE - The perceived or intrinsic WORTH of AN ASSET based on PURCHASE or development COSTS operations COSTS WORTH of information processed recovery expenes or any combination thereof. VALUE is relative to point- of- view.Threat- AN cvent
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可动凝胶深部调驱流线模拟方法研究 被引量:11
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作者 冯其红 袁士义 韩冬 《应用基础与工程科学学报》 EI CSCD 2005年第2期146-153,共8页
可动凝胶深部调驱过程中流体的流动涉及复杂的物理化学过程,快速准确地模拟该过程是参数优化、方案设计的关键.在建立起可动凝胶深部调驱的油水两相多组分数学模型的基础上,推导出了考虑重力和毛管力的三维流线模型,将求解饱和度的三维... 可动凝胶深部调驱过程中流体的流动涉及复杂的物理化学过程,快速准确地模拟该过程是参数优化、方案设计的关键.在建立起可动凝胶深部调驱的油水两相多组分数学模型的基础上,推导出了考虑重力和毛管力的三维流线模型,将求解饱和度的三维问题转化为一维问题.采用算子分离技术将流线上的饱和度方程分解为典型的双曲型方程和抛物型方程,并采用分数步差分法求解饱和度方程,利用显示方法解决了隐式问题,提高了求解精度和速度,从而实现了可动凝胶深部调驱的快速准确模拟. 展开更多
关键词 线 线
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