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3D Quantum Gravity, Localization and Particles beyond Standard Model
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作者 Risto Raitio 《Journal of High Energy Physics, Gravitation and Cosmology》 2025年第1期96-109,共14页
We review a 3d quantum gravity model, which incorporates massive spinning fields into the Euclidean path integral in a Chern-Simons formulation. Fundamental matter as defined in our previous preon model is recapped. B... We review a 3d quantum gravity model, which incorporates massive spinning fields into the Euclidean path integral in a Chern-Simons formulation. Fundamental matter as defined in our previous preon model is recapped. Both quantum gravity and the particle model are shown to be derivable from the supersymmetric 3d Chern-Simons action. Forces-Matter unification is achieved. 展开更多
关键词 Chern-Simons Theory Quantum Gravity Composite Particles Beyond Standard model
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Development of a new cerebral ischemia reperfusion model of Mongolian gerbils and standardized evaluation system 被引量:3
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作者 Ying Wu Caijiao Hu +9 位作者 Zhihui Li Feiyang Li Jianyi Lv Meng Guo Xin Liu Changlong Li Xueyun Huo Zhenwen Chen Lifeng Yang Xiaoyan Du 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第1期48-55,共8页
Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symp... Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symptoms are caused by numerous complex variant types of the circle.Additionally,the lack of an evaluation system for the cer-ebral ischemia/reperfusion(I/R)model of gerbils has shackled the application of this model.Methods:We created a symptom-oriented principle and detailed neurobehavioral scoring criteria.At different time points of reperfusion,we analyzed the alteration in locomotion by rotarod test and grip force score,infarct volume by triphenyltetrazo-lium chloride(TTC)staining,neuron loss using Nissl staining,and histological charac-teristics using hematoxylin-eosin(H&E)straining.Results:With a successful model rate of 56%,32 of the 57 gerbils operated by our method harbored typical features of cerebral I/R injury,and the mortality rate in the male gerbils was significantly higher than that in the female gerbils.The suc-cessfully prepared I/R gerbils demonstrated a significant reduction in motility and grip strength at 1 day after reperfusion;formed obvious infarction;exhibited typi-cal pathological features,such as tissue edema,neuronal atrophy and death,and vacuolated structures;and were partially recovered with the extension of reperfu-sion time.Conclusion:This study developed a new method for the unilateral common carotid artery ligation I/R model of gerbil and established a standardized evaluation system for this model,which could provide a new cerebral I/R model of gerbils with more practical applications. 展开更多
关键词 ISCHEMIA/REPERFUSION Mongolian gerbil standardized model system unilateral carotid occlusion
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Non-Uniform Pion Tetrahedron Aether and Electron Tetrahedron Model
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作者 Rami Rom 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期810-824,共15页
We propose that the QCD vacuum pion tetrahedron condensate density vary in space and drops to extremely low values in the Kennan, Barger and Cowie (KBC) void in analogy to earth’s atmospheric density drop with elevat... We propose that the QCD vacuum pion tetrahedron condensate density vary in space and drops to extremely low values in the Kennan, Barger and Cowie (KBC) void in analogy to earth’s atmospheric density drop with elevation from earth. We propose a formula for the gravitation acceleration based on the non-uniform pion tetrahedron condensate. Gravity may be due to the underlying microscopic attraction between quarks and antiquarks, which are part of the vacuum pion tetrahedron condensate. We propose an electron tetrahedron model, where electrons are comprised of tetraquark tetrahedrons, and . The quarks determine the negative electron charge and the or quarks determine the electron two spin states. The electron tetrahedron may perform a high frequency quark exchange reactions with the pion tetrahedron condensate by tunneling through the condensation gap creating a delocalized electron cloud with a fixed spin. The pion tetrahedron may act as a QCD glue bonding electron pairs in atoms and molecules and protons to neutrons in the nuclei. Conservation of valence quarks and antiquarks is proposed. 展开更多
关键词 Standard model (SM) QCD Vacuum Condensate Electric Dipole Moment (EDM) KBC Void ANTIMATTER MOND Theory Aether
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Constraints on Asymmetric Dark Matter in Quintessence Model
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作者 Sujuan Qiu Hoernisa Iminniyaz 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期599-608,共10页
The modified cosmology like quintessence model with kination phase predicted the Hubble expansion rate of the universe before Big Bang Nucleosynthesis is different from the standard cosmological scenario. The modified... The modified cosmology like quintessence model with kination phase predicted the Hubble expansion rate of the universe before Big Bang Nucleosynthesis is different from the standard cosmological scenario. The modified expansion rate leaves its imprint on the relic density of asymmetric dark matter. In this work, we review the calculation of relic density of asymmetric WIMP dark matter in the standard cosmological scenario and quintessence model with kination phase. Then we use the Planck data to find constraints on the annihilation cross section and the mass of the asymmetric dark matter in those models. 展开更多
关键词 Asymmetric Dark Matter Standard model Quintessence model
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An Investigation of the Harmonic Quark with an Energy-Mass Quantum of 253.4 GeV and How It Relates to the Heavy Particles of the Standard Model
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作者 Hongguang Yang Weidong Yang 《Journal of Modern Physics》 2024年第13期2347-2364,共18页
The understanding of the mechanism for the mass building of elementary particles of Standard Model (SM) has made significant progresses since the confirmation of the existence of the Higgs boson, in particular the rea... The understanding of the mechanism for the mass building of elementary particles of Standard Model (SM) has made significant progresses since the confirmation of the existence of the Higgs boson, in particular the realization that the mass of an elementary particle of SM is not “God-given” but is created by interactions with involved energy fields. Nevertheless, a sophisticated model to answer fundamental questions is still missing. Further research is needed to compensate for the existing deficit. The current paper is aimed to contribute to such research by using “harmonic quark series”. Harmonic quark series were introduced between 2003 and 2005 by O. A. Teplov and represented a relatively new approach to understanding the physical masses of elementary particles. Although they are not generally recognized, some research works have revealed very interesting and exciting facts regarding the mass quanta. The original harmonic quark series consists of mathematical “quark” entities with an energy-mass quantum between 7.87 MeV and 69.2 GeV. They obey a strict mathematical rule derived from the general harmonic oscillation theory. Teplov showed some quantitative relations between the masses of his harmonic quarks and the SM particles, especially in the intermediate mass range, i.e. mesons and hadrons up to 1000 MeV. Early research work also includes the investigation of H. Yang/W. Yang in the development of their so-called YY model for elementary particles (Ying-Yang model with “Ying” and “Yang” as quark components for a new theoretical particle framework). Based on Teplov’s scheme and its mathematical formula, they introduced further harmonic quarks down to 1 eV and showed some quantitative relationships between the masses of these harmonic quarks and the masses of electrons and up and down quarks. In this article, we will extend the harmonic quark series according to the Teplov scheme up to a new entity with a mass quantum of 253.4 GeV and show some interesting new mass relations to the heavy particles of the Standard Model (W boson, Z boson, top quark and Higgs boson). Based on these facts, some predictions will be made for experimental verification. We also hope that our investigation and result will motivate more researcher to dedicate their work to harmonic quark series in theory and in experiments. 展开更多
关键词 Harmonic Quark Series Teplov Mass Formula YY model for Atomic Kernel Standard model Particles MESONS W-BOSON Z-Boson Top Quark Higgs Boson
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Calculation of the Standard Model Parameters and Particles Based on a SU(4) Preon Model
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作者 Jan Helm 《Journal of Modern Physics》 2024年第1期64-124,共61页
This paper describes an extension and a new foundation of the Standard Model of particle physics based on a SU(4)-force called hyper-color, and on preon subparticles. The hyper-color force is a generalization of the S... This paper describes an extension and a new foundation of the Standard Model of particle physics based on a SU(4)-force called hyper-color, and on preon subparticles. The hyper-color force is a generalization of the SU(2)-based weak interaction and the SU(1)-based right-chiral self-interaction, in which the W-and the Z-bosons are Yukawa residual-field-carriers of the hyper-color force, in the same sense as the pions are the residual-field-carriers of the color SU(3) interaction. Using the method of numerical minimization of the SU(4)-action based on this model, the masses and the inner structure of leptons, quarks and weak bosons are calculated: the mass results are very close to the experimental values. We calculate also precisely the value of the Cabibbo angle, so the mixing matrices of the Standard model, CKM matrix for quarks and PMNS matrix for neutrinos can also be calculated. In total, we reduce the 29 parameters of the Standard Model to a total of 7 parameters. 展开更多
关键词 SU(4) Generalization of Weak Interaction Extension of Standard model Numerical Minimization of Action Hyper-Color Preon
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Calculation of Particle Decay Times in the Standard Model
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作者 Jan Helm 《Journal of Modern Physics》 2024年第3期271-321,共51页
We present here a two-step method of classification and calculation for decay rates in the Standard Model. The first step is a phenomenological classification method, which is an extended and improved schematic experi... We present here a two-step method of classification and calculation for decay rates in the Standard Model. The first step is a phenomenological classification method, which is an extended and improved schematic experimental formula for decay width originally introduced by Chang. This schematic formula separates decays into seven classes. Furthermore, from it is derived a process-specific interaction energy m<sub>X</sub>. The second step is a numerical calculation method, which calculates this interaction energy m<sub>X</sub> numerically by minimization of action from the Lagrangian of the process, from which follows the decay width via the phenomenological formula. The Lagrangian is based on an extension of the Standard Model, the extended SU(4)-preon-model. A comparison of numerically calculated and observed decay widths for a large selection of decays shows a good agreement. 展开更多
关键词 Particle Decay Decay Width Interaction Energy Minimization of Action Ex-tension of Standard model
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Toward Analytical Homogenized Relaxation Modulus for Fibrous Composite Material with Reduced Order Homogenization Method
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作者 Huilin Jia Shanqiao Huang Zifeng Yuan 《Computers, Materials & Continua》 SCIE EI 2025年第1期193-222,共30页
In this manuscript,we propose an analytical equivalent linear viscoelastic constitutive model for fiber-reinforced composites,bypassing general computational homogenization.The method is based on the reduced-order hom... In this manuscript,we propose an analytical equivalent linear viscoelastic constitutive model for fiber-reinforced composites,bypassing general computational homogenization.The method is based on the reduced-order homogenization(ROH)approach.The ROH method typically involves solving multiple finite element problems under periodic conditions to evaluate elastic strain and eigenstrain influence functions in an‘off-line’stage,which offers substantial cost savings compared to direct computational homogenization methods.Due to the unique structure of the fibrous unit cell,“off-line”stage calculation can be eliminated by influence functions obtained analytically.Introducing the standard solid model to the ROH method enables the creation of a comprehensive analytical homogeneous viscoelastic constitutive model.This method treats fibrous composite materials as homogeneous,anisotropic viscoelastic materials,significantly reducing computational time due to its analytical nature.This approach also enables precise determination of a homogenized anisotropic relaxation modulus and accurate capture of various viscoelastic responses under different loading conditions.Three sets of numerical examples,including unit cell tests,three-point beam bending tests,and torsion tests,are given to demonstrate the predictive performance of the homogenized viscoelastic model.Furthermore,the model is validated against experimental measurements,confirming its accuracy and reliability. 展开更多
关键词 Homogenized relaxation modulus VISCOELASTIC standard solid model reduced order homogenization fibrous composite material
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Attribute-Based Re-Encryption Scheme in the Standard Model 被引量:2
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作者 GUO Shanqing ZENG Yingpei +1 位作者 WEI Juan XU Qiuliang 《Wuhan University Journal of Natural Sciences》 CAS 2008年第5期621-625,共5页
In this paper, we propose a new attribute-based proxy re-encryption scheme, where a semi-trusted proxy, with some additional information, can transform a ciphertext under a set of attributes into a new ciphertext unde... In this paper, we propose a new attribute-based proxy re-encryption scheme, where a semi-trusted proxy, with some additional information, can transform a ciphertext under a set of attributes into a new ciphertext under another set of attributes on the same message, but not vice versa, furthermore, its security was proved in the standard model based on decisional bilinear Diffie-Hellman assumption. This scheme can be used to realize fine-grained selectively sharing of encrypted data, but the general proxy rencryption scheme severely can not do it, so the proposed schemecan be thought as an improvement of general traditional proxy re-encryption scheme. 展开更多
关键词 ATTRIBUTE-BASED re-encryption scheme standard model network storage
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Cryptanalysis and Improvement of a New Certificateless Signature Scheme in the Standard Model 被引量:1
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作者 Chenhuang Wu Hui Huang +1 位作者 Kun Zhou Chunxiang Xu 《China Communications》 SCIE CSCD 2021年第1期151-160,共10页
Digital signature,as an important cryptographic primitive,has been widely used in many application scenarios,such as e-commerce,authentication,cloud computing,and so on.Certificateless Public Key Cryptography(PKC)can ... Digital signature,as an important cryptographic primitive,has been widely used in many application scenarios,such as e-commerce,authentication,cloud computing,and so on.Certificateless Public Key Cryptography(PKC)can get rid of the certificate management problem in the traditional Public Key Infrastructure(PKI)and eliminate the key-escrow problem in the identity-based PKC.Lately,a new Certificateless Signature(CLS)scheme has been proposed by Kyung-Ah Shim(IEEE SYSTEMS JOURNAL,2018,13(2)),which claimed to achieve provable security in the standard model.Unfortunately,we present a concrete attack to demonstrate that the scheme cannot defend against the Type I adversary.In this type of attack,the adversary can replace the public key of the signer,and then he plays the role of the signer to forge a legal certificateless signature on any message.Furthermore,we give an improved CLS scheme to resist such an attack.In terms of the efficiency and the signature length,the improved CLS is preferable to the original scheme and some recently proposed CLS schemes in the case of precomputation. 展开更多
关键词 CERTIFICATELESS SIGNATURE standard model ATTACK
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Stability analysis of discrete-time BAM neural networks based on standard neural network models 被引量:1
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作者 张森林 刘妹琴 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第7期689-696,共8页
To facilitate stability analysis of discrete-time bidirectional associative memory (BAM) neural networks, they were converted into novel neural network models, termed standard neural network models (SNNMs), which inte... To facilitate stability analysis of discrete-time bidirectional associative memory (BAM) neural networks, they were converted into novel neural network models, termed standard neural network models (SNNMs), which interconnect linear dynamic systems and bounded static nonlinear operators. By combining a number of different Lyapunov functionals with S-procedure, some useful criteria of global asymptotic stability and global exponential stability of the equilibrium points of SNNMs were derived. These stability conditions were formulated as linear matrix inequalities (LMIs). So global stability of the discrete-time BAM neural networks could be analyzed by using the stability results of the SNNMs. Compared to the existing stability analysis methods, the proposed approach is easy to implement, less conservative, and is applicable to other recurrent neural networks. 展开更多
关键词 Standard neural network model (SNNM) Bidirectional associative memory (BAM) Linear matrix inequality (LMI) STABILITY Generalized eigenvalue problem (GEVP)
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Semi-Harmonic Scaling Enables Calculation of Masses of Elementary Particles of the Standard Model 被引量:1
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作者 Hans J.H.Geesink Dirk K.F.Meijer 《Journal of Modern Physics》 2018年第5期925-947,共23页
The underlying rules for a natural system describing cellular automata are simple, but produce highly complex behavior. A mathematical basis for the spectra of discrete coherent and non-coherent electromagnetic (EM) f... The underlying rules for a natural system describing cellular automata are simple, but produce highly complex behavior. A mathematical basis for the spectra of discrete coherent and non-coherent electromagnetic (EM) frequencies was derived, in which the algorithm exhibits an information distribution according to ratios of 2:3 in 1:2 at a semi-harmonic manner. This generalized music (GM) model shows that energy both in elementary particles and animate systems is semi-harmonic, quantized and discrete. A support for an ontological basis of the Standard Model was found, and indicates that the GM-model underlies the quantum field theory of subatomic particles. The present theory combines quantum mechanics and classical periodic systems, obeys to locality and solves the “hidden variable theory of Bohm”. The discovered pattern of electromagnetic field eigenvalues, within a broad range of discrete frequencies, points at a de Broglie/Bohm type of causal interpretation of quantum mechanics, implying an integral resonant pilot-wave/particle modality. The model has been substantiated by a meta-analysis of measured discrete energies of: 37 different Elementary Particles, 45 different EPR-measurements, zero-point energies of elements and about 450 electromagnetic wave frequencies of cells with a mean accuracy of 0.58%. It has been shown that the GM-scale is frequency-locked with zero-point oscillations, and thereby evidently implies involvement of entanglement. 展开更多
关键词 Algorithm Elementary Particles Coherent Wave Pattern Electromagnetic Fields Solitons Harmonics Cellular Automata Quantum Mechanics Standard model Einstein-Podolsky-Rosen BOHM Frohlich PYTHAGORAS
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Quantum Mechanics and General Relativity Identify Standard Model Particles as Black Holes 被引量:1
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作者 T. R. Mongan 《Journal of Modern Physics》 2022年第6期992-1000,共9页
The Standard Model of particle physics does not account for charged fermion mass values and neutrino mass, or explain why only three particles are in each charge state 0, -e/3, 2e/3, and -e. These issues are addressed... The Standard Model of particle physics does not account for charged fermion mass values and neutrino mass, or explain why only three particles are in each charge state 0, -e/3, 2e/3, and -e. These issues are addressed by treating Standard Model particles with mass m as spheres with diameter equal to their Compton wavelength l =&#295;/mc, where &#295;is Planck’s constant and c the speed of light, and any charge in diametrically opposed pairs ±ne/6 with n = 1, 2, or 3 at the axis of rotation on the sphere surface. Particles are ground state solutions of quantized Friedmann equations from general relativity, with differing internal gravitational constants. Energy distribution within particles identifies Standard Model particles with spheres containing central black holes with mass m, and particle spin resulting from black hole angular momentum. In each charge state, energy distribution within particles satisfies a cubic equation in l, allowing only three particles in the charge state and requiring neutrino mass. Cosmic vacuum energy density is a lower limit on energy density of systems in the universe, and setting electron neutrino average energy density equal to cosmic vacuum energy density predicts neutrino masses consistent with experiment. Relations between charged fermion wavelength solutions to cubic equations in different charge states determine charged fermion masses relative to electron mass as a consequence of charge neutrality of the universe. An appendix shows assigning charge ±e/6 to bits of information on the event horizon available for holographic description of physics in the observable universe accounts for dominance of matter over anti-matter. The analysis explains why only three Standard Models are in each charge state and predicts neutrino masses based on cosmic vacuum energy density as a lower bound on neutrino energy density. 展开更多
关键词 Standard model Particles Black Holes From Internal Gravity Neutrino Mass Prediction
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Neutral Higgs Boson Pair Production in Standard Model with the Fourth GenerationQuarks at LHC
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作者 SUNHao MAWen-Gan ZHOUYa-Jin SUNYan-Bin ZHANGRen-You HOUHong-Sheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1期73-78,共6页
We investigated the neutral Higgs boson pair production at the CERN Large Hadron Collider (LHC) in the SM with four families. We found that the gluon-gluon fusion mode is the most dominant one in producing neutral Hig... We investigated the neutral Higgs boson pair production at the CERN Large Hadron Collider (LHC) in the SM with four families. We found that the gluon-gluon fusion mode is the most dominant one in producing neutral Higgs boson pair at the LHC, and it can be used to probe the trilinear Higgs coupling. If the heavy quarks of the fourth generation really exist within the SM, they can manifest their effect on the cross section of the Higgs pair production process at the LHC. Our numerical results show that there will be neutral Higgs boson pair production events per year if the next generation heavy quarks really exist, while there will be only events produced per year if there are only three families in the SM. 展开更多
关键词 standard model four generations neutral Higgs boson pair production hadron collider
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Single Production of Heavy Top Quark from Three-Site Higgsless Model
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作者 岳崇兴 王丽红 闻佳 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第5期1613-1616,共4页
We consider single production of the heavy top quark T predicted by the three-site Higgsless model in future high energy collider experiments, such as the high energy linear e+ e- collider (ILC), the linear-ring ty... We consider single production of the heavy top quark T predicted by the three-site Higgsless model in future high energy collider experiments, such as the high energy linear e+ e- collider (ILC), the linear-ring type ep collider (THERA), and the CERN Large Hadron Collider (LHC). Our numerical results show that the possible signals of the heavy top quark T might be detected via the subproeess qb → q'T at the LHC. 展开更多
关键词 YANG-MILLS THEORY STANDARD model UNITARITY
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The Top-Charm Associated Production Within the R-Parity Violating Supersymmetric Model in Photon-Proton Collisions
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作者 HOUHong-sheng MAWen-Gan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第3期337-346,共10页
The top-charm associated production with the effects from both B- and L-violating interactions in TeV scale photon-proton collisions is investigated in the framework of minimal supersymmetric standard model. Within t... The top-charm associated production with the effects from both B- and L-violating interactions in TeV scale photon-proton collisions is investigated in the framework of minimal supersymmetric standard model. Within the bounds on the relevant R-parity violating couplings, the total cross section will reach the order of 10 fb in some parts of the parameter space. 展开更多
关键词 R-parity violation minimal supersymmetric standard model flavor changing neutral current
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Research of database-based modeling for mining management system
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作者 武海峰 金智新 白希军 《Journal of Coal Science & Engineering(China)》 2005年第1期98-101,共4页
Put forward the method to construct the simulation model automatically with database-based automatic modeling(DBAM) for mining system. Designed the standard simulation model linked with some open cut Pautomobile dispa... Put forward the method to construct the simulation model automatically with database-based automatic modeling(DBAM) for mining system. Designed the standard simulation model linked with some open cut Pautomobile dispatch system. Analyzed and finded out the law among them, and designed model maker to realize the automatic pro- gramming of the new model program. 展开更多
关键词 automatic modeling DBAM standard model model maker
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Estimate Totel Number of the Earth Atmospheric Particle with Standard Atmosphere model
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作者 GAOChong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第5期639-640,共2页
The total number of atmospheric particle (AP) is an important datum for planetary science and geoscience. Estimating entire AP number is also a familiar question in general physics. With standard atmosphere model, con... The total number of atmospheric particle (AP) is an important datum for planetary science and geoscience. Estimating entire AP number is also a familiar question in general physics. With standard atmosphere model, considering the number difference of AP caused by rough and uneven in the earth surface below, the sum of dry clean atmosphere particle is . So the whole number of AP including water vapor is . The rough estimation for the total number of AP on other planets (or satellites) in condensed state is also discussed on the base of it. 展开更多
关键词 planetary atmosphere earth atmosphere neutral atmosphere total number of atmospheric particle standard atmosphere model effect of uneven in the earth surface estimation
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STUDIES ON OPTIMUM MODELS FOR CULTIVATING DAHURIAN LARCH SEEDLINGS ON FRIGID REGIONS
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作者 宋景和 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1996年第2期6-10,共5页
The optimum models for cultivationg the seedlings of Dahurian Larch (Larix gmelim Rupr. ) were studied in the central nursery of Tahe Forestery Bureau from 1989 to 1993. The resultswerc as follows The optimum... The optimum models for cultivationg the seedlings of Dahurian Larch (Larix gmelim Rupr. ) were studied in the central nursery of Tahe Forestery Bureau from 1989 to 1993. The resultswerc as follows The optimum models of the main morphological standards of the seedlings were30000 kg /hm2 of' decomposed' ash for improviong soil, 70,000 kg/hm2 of excrement and 1,500 kg/hm2of' calcium superphosphate as basal fertilizer , and 500 kg/hm2 of (NH4)2HPO4 and 220 kg/hm2 of'urea as top dressing. During growth perlod of the seedlings, the growth was greatly checked when thesoil water suction (SWS) was uithin 50 ~ 73. 3 kPa or below 10 kPa but greatest when SWS waswithin 30 ~ 40 kPa in initial growth stage and within 10-20kPa in last growth stage. The method for determining the optimum sowing time is to measure the depth of soil thawing, accumulated temperature abovc 5℃ both at 5 cm of the depth of of soil and in atmosphere. In Tahe region, the optimumsowing trme for Dahurian larch for Dahuria larch is about on May 10 when the depth of soil thawing, the accumulatedtemperature above 5℃ at 5 cm of the depth and the accumulated temperature above 5℃ in atmosphere reaches 40 cm. abovc 46℃ and abovae 56℃ respectively. The optimum seedlings density forthis region is 600-800 individuals/m2. 展开更多
关键词 Dahurian larch Seedling Phenological rule Community effect Soil water management Standard quantitative model
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R-Parity Violation Effects on b_1 → bχ_1~0 in Minimal SupersymmetricStandard Model
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作者 ZHANGRen-You MAWen-Gan +2 位作者 JIANGYi HOUHong-Sheng SUNYan-Bin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期257-267,共11页
We investigate in detail the effects of R-parity lepton number violation onthe decay b_1 → bχ_1~0 in the R-parity violating minimal supersymmetric standard model (R_p-MSSM)under the present experimental constraints ... We investigate in detail the effects of R-parity lepton number violation onthe decay b_1 → bχ_1~0 in the R-parity violating minimal supersymmetric standard model (R_p-MSSM)under the present experimental constraints on R_p parameters. In our numerical calculations weconsider two cases of input parameters of the squark and slepton sectors, M_(squark) 【 M_(slepton)and M_(squark) 】 M_(slepton), for comparison. The results show that the relative R-parity violatingcorrection is not very sensitive to the mass of the lightest neutralino bχ_1~0 the degenerateR-parity violating coupling parameter λ′_2 but strongly depends on M_(squark), M_(slepton) tan βand tie degenerate R-parity violating coupling parameter λ′_1. The relative correction is about -4~ 3% and can exceed -6% in some region of parameter space. Therefore, precise experiment analyseson the decay b_1 → bχ_1~0 may provide a probe of the R-parity violation. 展开更多
关键词 minimal supersymmetric standard model R-parity violation
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