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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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Study on Operation of Arctic Offshore Complex by Means of Multicomponent Process-Based Simulation 被引量:1
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作者 Oleg V.Tarovik Alex Topaj +2 位作者 Andrey B.Krestyantsev Aleksander A.Kondratenko Dmitry A.Zaikin 《Journal of Marine Science and Application》 CSCD 2018年第4期471-497,共27页
We developed a detailed simulation model of the Arctic marine transport system(MTS) for oil platform Prirazlomnaya. The model has a multidisciplinary nature and involves: sub-models of various transport and technologi... We developed a detailed simulation model of the Arctic marine transport system(MTS) for oil platform Prirazlomnaya. The model has a multidisciplinary nature and involves: sub-models of various transport and technological processes; stochastic weather generator to obtain time series of 15 environmental parameters; and contextual planning algorithm to build voyage plan considering several types of ships and cargoes. We used a significant amount of real operational data to identify model parameters and to prove its statistical reliability. Our main scientific task is to investigate the interaction of various processes of a different nature, while the practical aim is to find a set of measures to increase the efficiency of MTS. The results of the study reveal many examples of the mutual interaction of various processes that need to be considered at the design stage to avoid technical mistakes.The study formed a basis for making managerial decisions at the top level of Gazprom Neft Shelf Company. 展开更多
关键词 Marine transport system Discrete event SIMULATION OFFSHORE oil platform Stochastic weather generator Vessel VOYAGE planning Supply VESSELS operation ARCTIC tankers
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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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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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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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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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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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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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对合作学习操作性策略的实验研究 被引量:5
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作者 许峰 李健 武玉强 《中国健康心理学杂志》 2005年第3期237-240,共4页
目的探讨合作学习操作过程中一种新的教学组织模式——学习中的“合作+竞争”对学生学业成绩、合作意识、竞争精神的影响,通过改变学生学业成绩的奖励模式,使学生在公平、有序的竞争环境中增强其学业竞争力和提高学业成绩的同时,培养学... 目的探讨合作学习操作过程中一种新的教学组织模式——学习中的“合作+竞争”对学生学业成绩、合作意识、竞争精神的影响,通过改变学生学业成绩的奖励模式,使学生在公平、有序的竞争环境中增强其学业竞争力和提高学业成绩的同时,培养学生的合作意识,训练学生的合作技巧。方法选取小学四年级和六年级的学生作为实验对象,采用自行设计的学业成绩奖励模式与现有的学业成绩奖励模式作为自变量进行比较实验。结果与对照班相比,实验班中的四年级和六年级学生语文成绩都有明显提高,差异显著;数学成绩六年级学生有明显提高,差异显著,而四年级学生的成绩差异不明显。结论采用新的学业成绩奖励模式,创设“合作+竞争”的教学组织模式,可以整体性的提高学生语文科目的学业成绩,提高学生的学业竞争力;可以培养学生的合作意识,掌握必要的合作技巧,有利于提高学生的社会适应性;可以促进学生参与公平、有序的竞争。 展开更多
关键词
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Current status and prospects of research on safety situation awareness of high speed railway operation environment
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作者 Tianyun Shi Zhoulong Wang +4 位作者 Jia You Pengyue Guo Lili Jiang Huijin Fu Xu Gao 《Railway Sciences》 2024年第4期453-468,共16页
Purpose–The safety of high-speed rail operation environments is an important guarantee for the safe operation of high-speed rail.The operating environment of the high-speed rail is complex,and the main factors affect... Purpose–The safety of high-speed rail operation environments is an important guarantee for the safe operation of high-speed rail.The operating environment of the high-speed rail is complex,and the main factors affecting the safety of high-speed rail operating environment include meteorological disasters,perimeter intrusion and external environmental hazards.The purpose of the paper is to elaborate on the current research status and team research progress on the perception of safety situation in high-speed rail operation environment and to propose directions for further research in the future.Design/methodology/approach–In terms of the mechanism and spatio-temporal evolution law of the main influencing factors on the safety of high-speed rail operation environments,the research status is elaborated,and the latest research progress and achievements of the team are introduced.This paper elaborates on the research status and introduces the latest research progress and achievements of the team in terms of meteorological,perimeter and external environmental situation perception methods for high-speed rail operation.Findings–Based on the technical route of“situational awareness evaluation warning active control,”a technical system for monitoring the safety of high-speed train operation environments has been formed.Relevant theoretical and technical research and application have been carried out around the impact of meteorological disasters,perimeter intrusion and the external environment on high-speed rail safety.These works strongly support the improvement of China’s railway environmental safety guarantee technology.Originality/value–With the operation of CR450 high-speed trains with a speed of 400 kmper hour and the application of high-speed train autonomous driving technology in the future,new and higher requirements have been put forward for the safety of high-speed rail operation environments.The following five aspects of work are urgently needed:(1)Research the single factor disaster mechanism of wind,rain,snow,lightning,etc.for high-speed railways with a speed of 400 kms per hour,and based on this,study the evolution characteristics of multiple safety factors and the correlation between the high-speed driving safety environment,revealing the coupling disastermechanism ofmultiple influencing factors;(2)Research covers multi-source data fusion methods and associated features such as disaster monitoring data,meteorological information,route characteristics and terrain and landforms,studying the spatio-temporal evolution laws of meteorological disasters,perimeter intrusions and external environmental hazards;(3)In terms of meteorological disaster situation awareness,research high-precision prediction methods for meteorological information time series along high-speed rail lines and study the realization of small-scale real-time dynamic and accurate prediction of meteorological disasters along high-speed rail lines;(4)In terms of perimeter intrusion,research amulti-modal fusion perception method for typical scenarios of high-speed rail operation in all time,all weather and all coverage and combine artificial intelligence technology to achieve comprehensive and accurate perception of perimeter security risks along the high-speed rail line and(5)In terms of external environment,based on the existing general network framework for change detection,we will carry out research on change detection and algorithms in the surrounding environment of highspeed rail. 展开更多
关键词 High-speed rail operating environment Situation awareness Meteorological disasters Perimeter invasion External environment
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恩纳乳膏在腹腔镜手术病人静脉穿刺中的应用 被引量:1
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作者 张兰梅 欧少瑛 +2 位作者 潘丽莹 雷小燕 蒋细英 《现代临床护理》 2005年第2期18-20,共3页
目的观察恩纳乳膏用于腹腔镜手术病人术前静脉穿刺的镇痛效果,以及了解病人对该项护理操作的满意程度。方法将100例妇科腹腔镜手术病人随机分为实验组和对照组各50例。实验组选择以穿刺点为中心,沿静脉走向均匀涂上恩纳乳膏,60min后选... 目的观察恩纳乳膏用于腹腔镜手术病人术前静脉穿刺的镇痛效果,以及了解病人对该项护理操作的满意程度。方法将100例妇科腹腔镜手术病人随机分为实验组和对照组各50例。实验组选择以穿刺点为中心,沿静脉走向均匀涂上恩纳乳膏,60min后选择18号套管针进行静脉穿刺,对照组选择相同部位,相同型号套管针,按常规操作进行静脉穿刺;记录两组穿刺前、穿刺时、穿刺后5min、10min、20min、30min心率、血压情况,评估病人疼痛分值及满意度。结果两组病人穿刺术均成功,实验组疼痛评分明显低于对照组(均P<0.01);穿刺时对照组比实验组的血压、心率变化更明显(均P<0.01);根据静脉穿刺产生的疼痛程度评价其满意度,实验组满意度为100%,对照组为10%,两组比较,P<0.05,差异有统计学意义。结论恩纳乳膏可减轻手术病人术前静脉穿刺时的疼痛,此项护理操作得到病人的认同,具有临床推广应用价值。 展开更多
关键词 穿 穿 0.05 穿 穿 穿
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基于地表水和地下水联合调控的水资源配置模型研究 被引量:9
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作者 杨丽丽 王云霞 +2 位作者 谢新民 叶勇 丁飞 《水电能源科学》 北大核心 2010年第7期23-26,共4页
基于水库与地下水联合运用的耦合模拟模型,建立了基于河道内与河道外生态环境需水及下游灌溉用水需求双重作用的水资源优化调控模型,研制和开发了集数据库、模型库和人机交互界面等于一体的水资源优化调控模型计算软件,并以沈阳市沈北... 基于水库与地下水联合运用的耦合模拟模型,建立了基于河道内与河道外生态环境需水及下游灌溉用水需求双重作用的水资源优化调控模型,研制和开发了集数据库、模型库和人机交互界面等于一体的水资源优化调控模型计算软件,并以沈阳市沈北地区为例进行了实证研究。通过对石佛寺供水系统不同组合方案长系列逐月调算和对比分析,提出了推荐的石佛寺供水系统地表水与地下水联合优化调控模式和设计供水规模。研究结果为沈阳市的协调发展尤其是沈北地区未来的跨越式发展提供了安全的供水保障,且可推动我国地表水与地下水联合优化调控理论研究和应用,为其他地区和流域开展类似工作提供参考。 展开更多
关键词 Ground WATER Surface WATER Joint operation Based ALLOCATION Model WATER RESOURCES
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Holistic Approach to Safety and Operational Stability: Analyzing VVER-1200 Reactor Dynamics in SGTR and AC Power Loss
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作者 Shaon Md Tariqur Rahman Md. Sadman Anjum Joarder +2 位作者 Antor Mahamudul Hashan Sharon Md Mahabubur Rahman Redar Hameed Ali 《Journal of Power and Energy Engineering》 2024年第9期102-130,共29页
VVER-1200 (Water-Water Energetic Reactor) represents a significant advancement in nuclear power generation, emphasizing the continuous analysis and enhancement of safety systems for reliable operation. The proposed st... VVER-1200 (Water-Water Energetic Reactor) represents a significant advancement in nuclear power generation, emphasizing the continuous analysis and enhancement of safety systems for reliable operation. The proposed study focuses on simulating combined scenarios involving steam generator tube rupture (SGTR) and AC power loss using core algorithms and models within personal computer transient analyzer (PCTRAN). Reactor kinetic equations, thermal-hydraulic balance, and safety system models are discussed to elucidate their role in simulating SGTR and AC power loss. Safety criteria, boundaries and initial conditions are outlined to provide a comprehensive understanding of the simulation framework. The analysis delves into dynamic behavior of VVER-1200, placing emphasis on thermal-hydraulic implications, essential reactor parameters, and radiation monitoring to facilitate impact evaluation. Continuous monitoring and maintenance of safety systems are underscored to ensure stable core cooling, particularly during proposed transient conditions. Through meticulous analysis and comparison with established benchmarks, this study contributes to bolstering the safety and reliability of VVER-1200 reactors by identifying vulnerabilities, assessing mitigation strategies, and refining emergency response protocols. Practical implications of this study offer a crucial understanding of reactor behavior, safety system performance, and emergency response strategies, thereby improving safety, optimizing operational practices, and reducing risks in nuclear reactor accidents. 展开更多
关键词 VVER-1200 Nuclear Technology safety Systems operational Efficiency Transient Events
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The Monty Hall Problem and beyond: Digital-Mathematical and Cognitive Analysis in Boole’s Algebra, Including an Extension and Generalization to Related Cases 被引量:1
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作者 Leo Depuydt 《Advances in Pure Mathematics》 2011年第4期136-154,共19页
The Monty Hall problem has received its fair share of attention in mathematics. Recently, an entire monograph has been devoted to its history. There has been a multiplicity of approaches to the problem. These approach... The Monty Hall problem has received its fair share of attention in mathematics. Recently, an entire monograph has been devoted to its history. There has been a multiplicity of approaches to the problem. These approaches are not necessarily mutually exclusive. The design of the present paper is to add one more approach by analyzing the mathematical structure of the Monty Hall problem in digital terms. The structure of the problem is described as much as possible in the tradition and the spirit—and as much as possible by means of the algebraic conventions—of George Boole’s Investigation of the Laws of Thought (1854), the Magna Charta of the digital age, and of John Venn’s Symbolic Logic (second edition, 1894), which is squarely based on Boole’s Investigation and elucidates it in many ways. The focus is not only on the digital-mathematical structure itself but also on its relation to the presumed digital nature of cognition as expressed in rational thought and language. The digital approach is outlined in part 1. In part 2, the Monty Hall problem is analyzed digitally. To ensure the generality of the digital approach and demonstrate its reliability and productivity, the Monty Hall problem is extended and generalized in parts 3 and 4 to related cases in light of the axioms of probability theory. In the full mapping of the mathematical structure of the Monty Hall problem and any extensions thereof, a digital or non-quantitative skeleton is fleshed out by a quantitative component. The pertinent mathematical equations are developed and presented and illustrated by means of examples. 展开更多
关键词 Binary Structure BOOLEAN ALGEBRA BOOLEAN Operators Booles ALGEBRA Brain Science Cognition COGNITIVE Science Digital MATHEMATICS Electrical Engineering Linguistics Logic Non-Quantitative and QUANTITATIVE MATHEMATICS Monty HALL Problem Neuroscience Probability Theory Rational Thought and Language
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