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World-Universe Model—Alternative to Big Bang Model 被引量:1
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2020年第1期133-158,共26页
This manuscript provides a comparison of the Hypersphere World-Universe Model (WUM) with the prevailing Big Bang Model (BBM) of the Standard Cosmology. The performed analysis of BBM shows that the Four Pillars of the ... This manuscript provides a comparison of the Hypersphere World-Universe Model (WUM) with the prevailing Big Bang Model (BBM) of the Standard Cosmology. The performed analysis of BBM shows that the Four Pillars of the Standard Cosmology are model-dependent and not strong enough to support the model. The angular momentum problem is one of the most critical problems in BBM. Standard Cosmology cannot explain how Galaxies and Extra Solar systems obtained their substantial orbital and rotational angular momenta, and why the orbital momentum of Jupiter is considerably larger than the rotational momentum of the Sun. WUM is the only cosmological model in existence that is consistent with the Law of Conservation of Angular Momentum. To be consistent with this Fundamental Law, WUM discusses in detail the Beginning of the World. The Model introduces Dark Epoch (spanning from the Beginning of the World for 0.4 billion years) when only Dark Matter Particles (DMPs) existed, and Luminous Epoch (ever since for 13.8 billion years). Big Bang discussed in Standard Cosmology is, in our view, transition from Dark Epoch to Luminous Epoch due to Rotational Fission of Overspinning Dark Matter (DM) Supercluster’s Cores. WUM envisions Matter carried from the Universe into the World from the fourth spatial dimension by DMPs. Ordinary Matter is a byproduct of DM annihilation. WUM solves a number of physical problems in contemporary Cosmology and Astrophysics through DMPs and their interactions: Angular Momentum problem in birth and subsequent evolution of Galaxies and Extrasolar systems—how do they obtain it;Fermi Bubbles—two large structures in gamma-rays and X-rays above and below Galactic center;Diversity of Gravitationally-Rounded Objects in Solar system;some problems in Solar and Geophysics [1]. WUM reveals Inter-Connectivity of Primary Cosmological Parameters and calculates their values, which are in good agreement with the latest results of their measurements. 展开更多
关键词 Big Bang MODEL Four Pillars of Standard Cosmology ANGULAR MOMENTUM Problem Black Holes Hypersphere World-Universe MODEL Multicomponent DARK MATTER Macroobjects Structure Law of Conservation of ANGULAR MOMENTUM Medium of the World Inter-Connectivity of Primary Cosmological Parameters The Beginning of the World DARK EPOCH Rotational Fission Luminous EPOCH Macroobject Shell MODEL DARK MATTER Core Gravitational Burst Intergalactic Plasma Microwave Background Radiation Far-Infrared Background Radiation Emergent Phenomena CODATA
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Dark Matter Cosmology and Astrophysics 被引量:8
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第4期999-1050,共52页
Hypersphere World-Universe Model (WUM) envisions Matter carried from Universe into World from fourth spatial dimension by Dark Matter Particles (DMPs). Luminous Matter is byproduct of Dark Matter (DM) annihilation. WU... Hypersphere World-Universe Model (WUM) envisions Matter carried from Universe into World from fourth spatial dimension by Dark Matter Particles (DMPs). Luminous Matter is byproduct of Dark Matter (DM) annihilation. WUM introduces Dark Epoch (spanning from Beginning of World for 0.4 billion years) when only DMPs existed, and Luminous Epoch (ever since for 13.8 billion years). Big Bang discussed in standard cosmological model is, in our view, transition from Dark Epoch to Luminous Epoch due to Rotational Fission of Overspinning DM Supercluster’s Cores and annihilation of DMPs. WUM solves a number of physical problems in contemporary Cosmology and Astrophysics through DMPs and their interactions: Angular Momentum problem in birth and subsequent evolution of Galaxies and Extrasolar systems—how do they obtain it;Fermi Bubbles—two large structures in gamma-rays and X-rays above and below Galactic center;Mysterious Star KIC 8462852 with irregular dimmings;Coronal Heating problem in solar physics—temperature of Sun’s corona exceeding that of photosphere by millions of degrees;Cores of Sun and Earth rotating faster than their surfaces;Diversity of Gravitationally-Rounded Objects in Solar system and their Internal Heat;Lightning Initiation problem—electric fields observed inside thunderstorms are not sufficient to initiate sparks;Terrestrial Gamma-Ray Flashes—bursts of high energy X-rays and gamma rays emanating from Earth. Model makes predictions pertaining to Masses of DMPs, proposes New Types of their Interactions. WUM reveals Inter-Connectivity of Primary Cosmological Parameters and calculates their values, which are in good agreement with the latest results of their measurements. 展开更多
关键词 Hypersphere World-Universe Model Law of Conservation of Angular Momentum DARK EPOCH Rotational Fission Luminous EPOCH Multiworld DARK MATTER Particles Macroobject Shell Model DARK MATTER Core Medium of the World Mysterious Star KIC 8462852 DARK MATTER Fermi Bubbles Solar CORONA Geocorona Planetary CORONA Galactic Wind Solar Wind High-Energy Atmospheric Physics Lightning Initiation Problem Terrestrial GAMMA-RAY Flashes GAMMA-RAY BURSTS Gravitational BURSTS Ball Lightning
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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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Means of Choice for Interactive Management of Dynamic Geometry Problems Based on Instrumented Behaviour
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作者 Philippe R. Richard Michel Gagnon +2 位作者 Josep Maria Fortuny Nicolas Leduc Michèle Tessier-Baillargeon 《American Journal of Computational Mathematics》 2013年第3期41-51,共11页
Our paper presents a project that involves two research questions: does the choice of a related problem by the tutorial system allow the problem solving process which is blocked for the student to be restarted? What i... Our paper presents a project that involves two research questions: does the choice of a related problem by the tutorial system allow the problem solving process which is blocked for the student to be restarted? What information about learning do related problems returned by the system provide us? We answer the first question according to the didactic engineering, whose mode of validation is internal and based on the confrontation between an a priori analysis and an a posteriori analysis that relies on data from experiments in schools. We consider the student as a subject whose adaptation processes are conditioned by the problem and the possible interactions with the computer environment, and also by his knowledge, usually implicit, of the institutional norms that condition his relationship with geometry. Choosing a set of good problems within the system is therefore an essential element of the learning model. Since the source of a problem depends on the student’s actions with the computer tool, it is necessary to wait and see what are the related to problems that are returned to him before being able to identify patterns and assess the learning. With the simultaneity of collecting and analysing interactions in each class, we answer the second question according to a grounded theory analysis. By approaching the problems posed by the system and the designs in play at learning blockages, our analysis links the characteristics of problems to the design components in order to theorize on the decisional, epistemological, representational, didactic and instrumental aspects of the subject-milieu system in interaction. 展开更多
关键词 DIDACTICS of Mathematics Competencies Geometric Thinking TUTORIAL System Related problems Dynamic Geometry Instrumented Behavior Cognitive Interactions CONCEPTIONS Mathematical Work Space MEANS of CHOICE Didactic Contract
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Chromosomal aberrations and nucleic acids systems affected by some Egyptian medicinal plants used in treating female pregnant diabetic rats
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作者 Halima S . Abdou Sherifa H. Salah +1 位作者 Amira Abd El Raouf E.A. Abdel-Rahim 《American Journal of Molecular Biology》 2011年第1期26-32,共7页
The influences of medicinal plants Juniperus Phoenicea (Araar), Hyphaene thebaica (Doum), An-astatica hierochuntica (Kafta) and Cleome droserifolia (Sammo) as antidiabetic agents were investigated using female pregnan... The influences of medicinal plants Juniperus Phoenicea (Araar), Hyphaene thebaica (Doum), An-astatica hierochuntica (Kafta) and Cleome droserifolia (Sammo) as antidiabetic agents were investigated using female pregnant albino rats. Female rats were injected with 60 mg/kg b.w. alloxan to induce diabe-tes. Diabetic rats treated orally with the methanol extracts of tested plants till the 19 day of gestation. The present studies include the frequencies of chro-mosomal aberrations and nucleic acid system of liver in the female pregnant rats and their embryos. The results showed that injection of alloxan caused highly significant increase in chromosomal aberrations as well as in blood glucose levels as a result of diabetes in pregnant females. It also caused a high incidence of chromosomal deviation in embryos and decreased the liver soluble protein contents of female rats and their embryos. These effects in alloxanized animals were treated and improved by ingestion of the methanol extracts of the tested plants (Araar, Doum, Kafta and Somma) in which under their treatments, the inceased level of blood glu-cose of diabetic rats was deceased. Ingestion with the plants methanolic extracts improved and normalized the effects of diabetes in nucleic acids values of liver tissues. These were accompanied with nucleases (RNAase and DNAase) activities. The inhibited ac-tivities of both DNA ase and RNA ase of pregnant rats and their embryos were stimulated and read-justed around the normal values. Also administration of the plants methanol extracts decreased the per-centage of chromosomal aberrations in the female rats and embryos. It is concluded that there are some biochemical dynamics which might occur in the metabo-lism of glucose, nucleic acids and proteins in order to prevent or to reduce the oxidative stress of diabetes by flavonoides treatment. 展开更多
关键词 Tested Plants: CLEOME Droserfolia (Sommo) Jumiperus PHOENICIA (Araar) Anostatica Hierochuntica (Kafta) And Hyphened Thebaica (Doum) ALLOXAN PREGNANT females ALBINO Rats Diabetes Mellitus
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Numerical Exploration of Asymmetrical Impact Dynamics: Unveiling Nonlinearities in Collision Problems and Resilience of Reinforced Concrete Structures
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作者 AL-Bukhaiti Khalil Yanhui Liu +1 位作者 Shichun Zhao Daguang Han 《Structural Durability & Health Monitoring》 EI 2024年第3期223-254,共32页
This study provides a comprehensive analysis of collision and impact problems’ numerical solutions, focusing ongeometric, contact, and material nonlinearities, all essential in solving large deformation problems duri... This study provides a comprehensive analysis of collision and impact problems’ numerical solutions, focusing ongeometric, contact, and material nonlinearities, all essential in solving large deformation problems during a collision.The initial discussion revolves around the stress and strain of large deformation during a collision, followedby explanations of the fundamental finite element solution method for addressing such issues. The hourglassmode’s control methods, such as single-point reduced integration and contact-collision algorithms are detailedand implemented within the finite element framework. The paper further investigates the dynamic responseand failure modes of Reinforced Concrete (RC) members under asymmetrical impact using a 3D discrete modelin ABAQUS that treats steel bars and concrete connections as bond slips. The model’s validity was confirmedthrough comparisons with the node-sharing algorithm and system energy relations. Experimental parameterswere varied, including the rigid hammer’s mass and initial velocity, concrete strength, and longitudinal and stirrupreinforcement ratios. Findings indicated that increased hammer mass and velocity escalated RC member damage,while increased reinforcement ratios improved impact resistance. Contrarily, increased concrete strength did notsignificantly reduce lateral displacement when considering strain rate effects. The study also explores materialnonlinearity, examining different materials’ responses to collision-induced forces and stresses, demonstratedthrough an elastic rod impact case study. The paper proposes a damage criterion based on the residual axialload-bearing capacity for assessing damage under the asymmetrical impact, showing a correlation betweendamage degree hammer mass and initial velocity. The results, validated through comparison with theoreticaland analytical solutions, verify the ABAQUS program’s accuracy and reliability in analyzing impact problems,offering valuable insights into collision and impact problems’ nonlinearities and practical strategies for enhancingRC structures’ resilience under dynamic stress. 展开更多
关键词 Geometric nonlinearity contact nonlinearity material nonlinearity collision problems finite element method stress and strain damage criterion RC members asymmetrical impact
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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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变系数三阶周期边值问题的正解(英文) 被引量:2
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作者 姚庆六 《吉首大学学报(自然科学版)》 CAS 2010年第6期9-13,共5页
研究了变系数非线性三阶周期边值问题的正解.非线性项可以关于空间变元奇异.利用适当的变换此问题被转换为一个Hammerstein积分方程,利用锥上的Guo-Krasno-selski不动点定理获得了1~2个正解的存在性.
关键词 VARIABLE COEFFICIENT BOUNDARY VALUE problems Solutions fixed point theorem on cone Hammerstein BOUNDARY VALUE problem VARIABLE COEFFICIENT positive solutions transformation nonlinear term 线 existence making
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Exact Distributions of Waiting Time Problems of Mixed Frequencies and Runs in Markov Dependent Trials 被引量:1
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作者 Bruce J. Chaderjian Morteza Ebneshahrashoob Tangan Gao 《Applied Mathematics》 2012年第11期1689-1696,共8页
We study waiting time problems for first-order Markov dependent trials via conditional probability generating functions. Our models involve α frequency cells and β run cells with prescribed quotas and an additional ... We study waiting time problems for first-order Markov dependent trials via conditional probability generating functions. Our models involve α frequency cells and β run cells with prescribed quotas and an additional γ slack cells without quotas. For any given and , in our Model I we determine the waiting time until at least frequency cells and at least run cells reach their quotas. For any given τ ≤ α + β, in our Model II we determine the waiting time until τ cells reach their quotas. Computer algorithms are developed to calculate the distributions, expectations and standard deviations of the waiting time random variables of the two models. Numerical results demonstrate the efficiency of the algorithms. 展开更多
关键词 Inverse Sampling MULTINOMIAL STOPPING Problem Soonest through Latest WAITING Time Variable Probability Generating Function First-Order MARKOV DEPENDENT Trial
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Optimal Shape Factor and Fictitious Radius in the MQ-RBF:Solving Ill-Posed Laplacian Problems
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作者 Chein-Shan Liu Chung-Lun Kuo Chih-Wen Chang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3189-3208,共20页
To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection techniq... To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection technique is developed to identify the optimal shape factor and fictitious radius by minimizing a merit function.A sample function is interpolated by theMQ-RBF to provide a trial coefficient vector to compute the merit function.We can quickly determine the optimal values of the parameters within a preferred rage using the golden section search algorithm.The novel method provides the optimal values of parameters and,hence,an optimal MQ-RBF;the performance of the method is validated in numerical examples.Moreover,nonharmonic problems are transformed to the Poisson equation endowed with a homogeneous boundary condition;this can overcome the problem of these problems being ill-posed.The optimal MQ-RBF is extremely accurate.We further propose a novel optimal polynomial method to solve the nonharmonic problems,which achieves high precision up to an order of 10^(−11). 展开更多
关键词 Laplace equation nonharmonic boundary value problem Ill-posed problem maximal projection optimal shape factor and fictitious radius optimal MQ-RBF optimal polynomial method
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Female Warriors in the MCU and Wuxia Films:A Comparative Study
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作者 YE Wan-hua 《Journal of Literature and Art Studies》 2024年第5期386-394,共9页
This essay offers a comprehensive comparative analysis of female warriors in the Marvel Cinematic Universe(MCU)and Wuxia films.Both genres portray powerful and empowered female characters who defy societal expectation... This essay offers a comprehensive comparative analysis of female warriors in the Marvel Cinematic Universe(MCU)and Wuxia films.Both genres portray powerful and empowered female characters who defy societal expectations and embody resilience,effectively challenging gender norms and promoting female empowerment.However,despite their strength,many of these women warriors face certain narrative factors,such as the male gaze and a predetermined fate,which can restrict their agency and curtail their full potential.And it is within the realm of Wuxia films that the captivating element of cross-dressing among female warriors emerges,providing a nuanced exploration of identity and the constraints imposed by society. 展开更多
关键词 female warriors Marvel Cinematic Universe Wuxia films strength and agency male gaze predetermined fate cross-dressing
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Analytical Solutions of Some Two-Point Non-Linear Elliptic Boundary Value Problems
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作者 Vembu Ananthaswamy Lakshmanan Rajendran 《Applied Mathematics》 2012年第9期1044-1058,共15页
Several problems arising in science and engineering are modeled by differential equations that involve conditions that are specified at more than one point. The non-linear two-point boundary value problem (TPBVP) (Br... Several problems arising in science and engineering are modeled by differential equations that involve conditions that are specified at more than one point. The non-linear two-point boundary value problem (TPBVP) (Bratu’s equation, Troesch’s problems) occurs engineering and science, including the modeling of chemical reactions diffusion processes and heat transfer. An analytical expression pertaining to the concentration of substrate is obtained using Homotopy perturbation method for all values of parameters. These approximate analytical results were found to be in good agreement with the simulation results. 展开更多
关键词 TWO-POINT ELLIPTIC Boundary Value problems Bratus Equation Troeschs Problem NON-LINEAR Equations HOMOTOPY PERTURBATION Method Porous Catalyst Numerical Simulation
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Element Free Gelerkin Method for 2-D Potential Problems
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作者 Ali Rahmani Firoozjaee Ehsan Hendi Farzad Farvizi 《Applied Mathematics》 2015年第1期149-162,共14页
A meshfree method namely, element free Gelerkin (EFG) method, is presented in this paper for the solution of governing equations of 2-D potential problems. The EFG method is a numerical method which uses nodal points ... A meshfree method namely, element free Gelerkin (EFG) method, is presented in this paper for the solution of governing equations of 2-D potential problems. The EFG method is a numerical method which uses nodal points in order to discretize the computational domain, but where the use of connectivity is absent. The unknowns in the problems are approximated by means of connectivity-free technique known as moving least squares (MLS) approximation. The effect of irregular distribution of nodal points on the accuracy of the EFG method is the main goal of this paper as a complement to the precedent researches investigated by proposing an irregularity index (II) in order to analyze some 2-D benchmark examples and the results of sensitivity analysis on the parameters of the method are presented. 展开更多
关键词 ELEMENT Free GALERKIN (EFG) METHOD Potential problems Moving Least SQUARES Approximation Irregular Distribution of Nodal Points IRREGULARITY Index
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Estimation of Sensitivity of the DS/AHP Method While Solving Foresight Problems with Incomplete Data 被引量:2
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作者 N. Pankratova N. Nedashkovskaya 《Intelligent Control and Automation》 2013年第1期80-86,共7页
The paper provides mathematical analysis of sensitivity of different combination rules in the DS/AHP method when an alternative is added to the set of decision alternatives while solving foresight problems. Different ... The paper provides mathematical analysis of sensitivity of different combination rules in the DS/AHP method when an alternative is added to the set of decision alternatives while solving foresight problems. Different cases of rank reversals are defined and two sets of conditions for these cases using the method DS/AHP are considered. Rank reversals are illustrated when the DS/AHP method is used to solve practical problem of critical technologies of energy conservation and power efficiency evaluation in Ukraine. It is shown that the DS/AHP method is not sensitive to exclusion (or addition) of an irrelevant decision alternative from (or to) the set of decision alternatives. 展开更多
关键词 ANALYTIC Hierarchy Process DEMPSTER-SHAFER Theory INCOMPLETE Expert Information Multiple Criteria Analysis Combination Rules Rank REVERSAL FORESIGHT problems
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New pharmacological approaches against chronic bowel and bladder problems in paralytics 被引量:1
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作者 Pierre A Guertin 《World Journal of Critical Care Medicine》 2016年第1期1-6,共6页
Spinal cord injury(SCI) leads generally to an irreversible loss of sensory functions and voluntary motor control below injury level. Cures that could repair SCI and/or restore voluntary walking have not been yet devel... Spinal cord injury(SCI) leads generally to an irreversible loss of sensory functions and voluntary motor control below injury level. Cures that could repair SCI and/or restore voluntary walking have not been yet developed nor commercialized. Beyond the well-known loss of walking capabilities, most SCI patients experience also a plethora of motor problems and health concerns including specific bladder and bowel dysfunctions. Indeed, chronic constipation and urinary retention, two significant life-threatening complications, are typically found in patients suffering of traumatic(e.g., falls or car accidents) or non-traumatic SCI(e.g., multiple sclerosis, spinal tumors). Secondary health concerns associated with these dysfunctions include hemorrhoids, abdominal distention, altered visceral sensitivity, hydronephrosis, kidney failure, urinary tract infections, sepsis and, in some cases, cardiac arrest. Consequently, individuals with chronic SCI are forced to regularly seek emergency and critical care treatments when some of these conditions occur or become intolerable. Increasing evidence supports the existence of a novel experimental approach that may be capable of preventing the occurrence or severity of bladder and bowel problems. Indeed, recent findings in animal models of SCI have revealed that, despite paraplegia or tetraplegia, it remains possible to elicit episodes of micturition and defecation by acting pharmacologically or electrically upon specialized lumbosacral neuronal networks, namely the spinal or sacral micturition center(SMC) and lumbosacral defecation center(LDC). Daily activation of SMC and LDC neurons could potentially become, new classes of minimally invasive treatments(i.e., if orally active) against these dysfunctions and their many lifethreatening complications. 展开更多
关键词 Prevention of intensive CARE problems Quality of CARE Temporary recovery of VITAL functions MICTURITION DEFECATION Spinal networks Central pattern generators
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Two-Dimensional Riemann Problems:Transonic Shock Waves and Free Boundary Problems
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作者 Gui-Qiang G.Chen 《Communications on Applied Mathematics and Computation》 2023年第3期1015-1052,共38页
We are concerned with global solutions of multidimensional(M-D)Riemann problems for nonlinear hyperbolic systems of conservation laws,focusing on their global configurations and structures.We present some recent devel... We are concerned with global solutions of multidimensional(M-D)Riemann problems for nonlinear hyperbolic systems of conservation laws,focusing on their global configurations and structures.We present some recent developments in the rigorous analysis of two-dimensional(2-D)Riemann problems involving transonic shock waves through several prototypes of hyperbolic systems of conservation laws and discuss some further M-D Riemann problems and related problems for nonlinear partial differential equations.In particular,we present four different 2-D Riemann problems through these prototypes of hyperbolic systems and show how these Riemann problems can be reformulated/solved as free boundary problems with transonic shock waves as free boundaries for the corresponding nonlinear conservation laws of mixed elliptic-hyperbolic type and related nonlinear partial differential equations. 展开更多
关键词 Riemann problems Two-dimensional(2-D) Transonic shocks Solution structure Free boundary problems Mixed elliptic-hyperbolic type Global configurations Large-time asymptotics Global attractors Multidimensional(M-D) Shock capturing methods
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跨进21世纪的音乐人类学:国际潮流与中国实践 被引量:24
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作者 杨沐 《星海音乐学院学报》 2009年第4期1-19,共19页
本文讨论当代音乐人类学的理论范式转移及其在20~21世纪之交的国际潮流和研究路向,梳理归纳出该学科这一时期的主要论题并结合中国实例说明它们跟音乐实践和研究的关系以及当代理论的应用。所举实例包括作者长期考察研究的福州游神乐... 本文讨论当代音乐人类学的理论范式转移及其在20~21世纪之交的国际潮流和研究路向,梳理归纳出该学科这一时期的主要论题并结合中国实例说明它们跟音乐实践和研究的关系以及当代理论的应用。所举实例包括作者长期考察研究的福州游神乐舞、海南儋州调声、黎族民俗音乐、西北花儿等。作者还针对国内人类学界和音乐学界的有关现象进行反思,提出自己的批评和见解,涉及民族、族群、民族主义、国家主义、跨国主义等术语在英汉对译上的错误与误读以及由此导致的学术表述和研究中的混乱、伪民俗现象以及对待非物质文化遗产的态度与做法等问题。 展开更多
关键词
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Existence of Solutions for Boundary Value Problems of Conformable Fractional Differential Equations
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作者 Xingyue Jian 《Journal of Applied Mathematics and Physics》 2019年第1期233-242,共10页
In this paper, we study a class of boundary value problems for conformable fractional differential equations under a new definition. Firstly, by using the monotone iterative technique and the method of coupled upper a... In this paper, we study a class of boundary value problems for conformable fractional differential equations under a new definition. Firstly, by using the monotone iterative technique and the method of coupled upper and lower solution, the sufficient condition for the existence of the boundary value problem is obtained, and the range of the solution is determined. Then the existence and uniqueness of the solution are proved by the proof by contradiction. Finally, a concrete example is given to illustrate the wide applicability of our main results. 展开更多
关键词 Boundary Value problems Conformable Fractional Differential Equations The Method of COUPLED UPPER and Lower SOLUTION COUPLED SOLUTION MONOTONE ITERATION
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As Could We Assure Safety in Large-Scale Manufacturing of Nanoparticles for the Biomedical Use
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作者 Kirill Serguey Maksimov Serguei Kirillovich Maksimov Nikolay Dmitrievich Soukhov 《Journal of Biomaterials and Nanobiotechnology》 2011年第5期601-613,共13页
Nanoparticles provide great advantages but also great risks. Risks associating with nanoparticles are the problem of all technologies, but they increase in many times in nanotechnologies. Adequate methods of outgoing ... Nanoparticles provide great advantages but also great risks. Risks associating with nanoparticles are the problem of all technologies, but they increase in many times in nanotechnologies. Adequate methods of outgoing production inspection are necessary to solve the problem of risks, and the inspection must be based on the safety standard. Existing safety standard results from a principle of “maximum permissible concentrations or MPC”. This principle is not applicable to nanoparticles, but a safety standard reflecting risks inherent in nanoparticles doesn’t exist. Essence of the risks is illustrated by the example from pharmacology, since its safety assurance is conceptually based on MPC and it has already come against this problem. Possible formula of safety standard for nanoparticles is reflected in many publications, but conventional inspection methods cannot provide its realization, and this gap is an obstacle to assumption of similar formulas. Therefore the development of nanoparticle industry as a whole (also development of the pharmacology in particular) is impossible without the creation of an adequate inspection method. There are suggested new inspection methods founded on the new physical principle and satisfying to the adequate safety standard for nanoparticles. These methods demonstrate that creation of the adequate safety standard and the outgoing production inspection in a large-scale manufacturing of nanoparticles are the solvable problems. However there is a great distance between the physical principle and its hardware realization, and a transition from the principle to the hardware demands great intellectual and material costs. Therefore it is desirable to call attention of the public at large to the necessity of urgent expansions of investigations associated with outgoing inspections in nanoparticles technologies. It is necessary also to attract attention, first, of representatives of state structures controlling approvals of the adequate safety standard to this problem, since it is impossible to compel producers providing the safety without the similar standard, and, second, of leaders of pharmacological industry, since their industry already entered into the nanotechnology era, and they have taken an interest in a forthcoming development of inspection methods. 展开更多
关键词 Risks of NANOPARTICLE LARGE-SCALE MANUFACTURING Adequate SAFETY Standard Outgoing Production Inspection Structure and HABIT Scanning ELECTRON Microscopy HABIT Control by Means of Convergent Illuminating ELECTRON Beams SAFETY Assurance in the NANOPARTICLE Industry Is a Solvable Problem
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An overview of the resources and environment conditions and major geological problems in the Yangtze River economic zone, China 被引量:7
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作者 Yue-hua Jiang Liang-jun Lin +16 位作者 Li-de Chen Hua-yong Ni Wei-ya Ge Hang-xin Cheng Gang-yi Zhai Gui-ling Wang Yi-zhong Ban Yuan Li Ming-tang Lei Cheng-xuan Tan Jing-wen Su Quan-ping Zhou Tai-li Zhang Yun Li Hong-ying Liu Ke Peng Han-mei Wang 《China Geology》 2018年第3期435-449,共15页
Focusing on the Yangtze River economic zone,the previous geological researches are systematically summarized,resources and environment conditions and major geological problems which are needing to be concerned in land... Focusing on the Yangtze River economic zone,the previous geological researches are systematically summarized,resources and environment conditions and major geological problems which are needing to be concerned in land planning and construction are studied.The results show that the resource conditions of cultivated land,shale gas,geotherm,lithium and so on are superior in the Yangtze River economic zone,and the resources and environment conditions are conducive to develop the modern agriculture,clean energy industry and strategic emerging industries.3×1013 m^2 farmlands without heavy metal pollution are concentrated;there are three national level shale gas exploration and development bases with explored reserves of 5.441×1011 m^3;geothermal availability is 2.4×109 t of standard coal each year,equivalent to 19% of the amount of coal in 2014;Asia's largest energy lithium metal ore deposit is found.In some parts of Yangtze River economic zone,there are some major geological problems such as active faults,karst collapse,ground subsidence,landslide-collapse-debris flow,affecting the river-crossing channels,high-speed railway,urban agglomeration and green ecological corridor planning and construction.Those problems should be concerned,and the relevant suggestions and countermeasures are put forward.Meanwhile,the ideas to further support the development of the Yangtze River economic zone are put forward. 展开更多
关键词 The Yangtze River economic zone Resources and environment CONDITIONS MAJOR geological problems Environmental GEOLOGY HYDROGEOLOGY Disaster GEOLOGY
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