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Optimal Proportional Reinsurance for Controlled Risk Process which is Perturbed by Diffusion

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Acta Mathematicae Applicatae Sinica 2007年第3期23卷 477-488页

作者： zhi-bin liang Institute of Mathematics and Computer Science Nanjing Normal University Nanjing 210097 China School of Mathematical Sciences and LPMC Nankai University Tianjin 300071 China

In this paper, we study optimal proportional reinsurance policy of an insurer with a risk process which is perturbed by a diffusion. We derive closed-form expressions for the policy and the value function, which are optimal in the sense of maximizing the expected utility in the jump-diffusion framework. We also obtain explicit expressions for the policy and the value function, which are optimal in the sense of maximizing the expected utility or maximizing the survival probability in the diffusion approximation case. Some numerical examples are presented, which show the impact of model parameters on the policy. We also compare the results under the different criteria and different cases.

关键词： Stochastic control Hamilton-Jacobi-Bellman equation jump-diffusion brownian motion diffusion approximation proportional reinsurance

Graphdiyne(C_(n)H_(2n-2))as an"electron transfer bridge"boosting photocatalytic hydrogen evolution over Zn_(0.5)Co_(0.5)S/MoS_(2)S-scheme heterojunction

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Rare Metals 2024年第5期43卷 1999-2014页

作者： Mei Li Jing-zhi Wang zhi-liang Jin School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan 750021China School of Chemistry and Chemical Engineering Ningxia Key Laboratory of Solar Chemical Conversion TechnologyKey Laboratory for Chemical Engineering and TechnologyState Ethnic Affairs CommissionNorth Minzu UniversityYinchuan 750021China

In the process of photocatalytic water cracking,the migration rate and utilization rate of photogenerated charges determine the hydrogen evolution performance of the *** this paper,a carbon isotope superconducting material graphdiyne(GDY)is prepared by mechanical ball milling and introduced into the S-scheme heterojunction Zn_(0.5)Co_(0.5)S/MoS_(2)inorganic *** terms of hydrogen evolution kinetics,GDY acts as an electron bridge,not only accelerating the migration of photogenerated carriers but also improving the utilization of photogenerated ***,the large twodimensional layer provides more loading and anchoring points for Zn_(0.5)Co_(0.5)S/MoS_(2),which increases the number of active *** ternary composite catalyst 20%GDY/Zn_(0.5)Co_(0.5)S/MoS_(2)(20-GCSM)generates 69.94μmol of hydrogen(5 h)in triethanolamine *** is 2.97 and1.80 times higher than Zn_(0.5)Co_(0.5)S and Zn_(0.5)Co_(0.5)S/MoS_(2),*** the cyclic experiment,it still has stable hydrogen evolution performance after standing for24 h(under dark conditions).In addition,the potential mechanism of photocatalytic hydrogen evolution is demonstrated through in-situ X-ray photoelectron *** work provides a reference for further research in the field of introducing carbon materials into photocatalytic systems and improving the utilization of photogenerated charges.

关键词： Graphdiyne S-scheme heterojunction Electron transfer bridge Hydrogen production

Synthesis and analysis of new humidity-controlling composite materials

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International Journal of Minerals,Metallurgy and Materials 2017年第5期24卷 594-602页

作者： Jian-li shang zhi-fang Zong Hao Zhang College of Materials and Mineral Resources Xi’an University of Architecture and TechnologyXi’an 710055China

Gypsum is a traditional building material. To improve the humidity-controlling properties of gypsum, we prepared a new type of humidity-controlling composite using the sol-gel method. Methods to determine the maximum equilibrium moisture content and speed of adsorption/desorption were subsequently applied to analyze the performance of the samples. The appearance and structural properties of the samples were characterized by scanning electronic microscopy (SEM). The experimental results show that the humidity-controlling gel with added LiCl exhibits high moisture storage and that the equilibrium maximum moisture content is 5.652 g/g at a 75.29% relative humidity (RH). A mass ratio of LiCl/sol = 0.15 is demonstrated to be appropriate for the preparation of the new humidity-controlling composites. A coarse network with tiny pores is observed on the surface of the new humidity-controlling composites, and this pore network provides sufficient space for moisture adsorption.

关键词： composite materials gypsum humidity control sol-gel processing adsorption desorption

On d-row(Column) Antimagic Matrices and Subset Partitions

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Acta Mathematicae Applicatae Sinica 2021年第1期37卷 192-200页

作者： zhi-he liang Shi-xin liang School of Mathematical Science Hebei Normal UniversityShijiazhuang 050024China ABB Electric Transmission Systems Co.LTD Beijing 100020China

An m×k matrix is said to be a d-row(column)antimagic matrix if its row-sums(column-sums)form an arithmetic progression with a difference *** goal of this paper is to obtain the existence theorems and construction methods of some d-row(column)antimagic *** these results we give the necessary and sufficient condition for the existence of an(m,d)-partition of[1,mk].

关键词： matrix d-row(column)antimagic matrix subset partition

A Note on Calculation of Phase Space Path Integral by Means of Invariants

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Communications in Theoretical Physics 2006年第5期45卷 813-814页

作者： QIAN shang-Wu GU zhi-Yu physics Department Peking University Beijing 100871 China physics Department Capital Normal University Beijing 100037 China

In this note we use the method of invariant to calculate the phase space path integral appearing in our previous article.

关键词： phase space path integral invariant propagator

Evolutions of Yang Phase Under Cyclic Condition and Adiabatic Condition

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Communications in Theoretical Physics 2005年第2X期44卷 243-246页

作者： QIAN shang-Wu GU zhi-Yu Physics Department Peking University Beijing 100871 China Physics Department Capital Normal University Beijing 100037 China

There are three non-integrable phases in literatures: Berry phase, Aharonov-Anandan phase, and Yang phase. This article discusses the evolutions of Yang phase under the cyclic condition and the adiabatic condition for the generaltime-dependent harmonic oscillator, thus reveals the intimate relations between these three non-integrable phases.

关键词： Berry phase A-A phase Yang phase general time-dependent harmonic oscillator

Knotted Picture of Unknown Quantum State in Process of Quantum Teleportation

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Communications in Theoretical Physics 2008年第5期49卷 1163-1164页

作者： GU zhi-Yu QIAN shang-Wu Physics Department Capital Normal University Beijing 100037 China Physics Department Peking University Beijing 100871 China

This paper gives the knotted picture of the unknown quantum state in the process of quantum teleportation and the surgical knotted operations of the unitary operators operated on the teleported quantum state.

关键词： Bell bases single particle quantum state knotted picture flip operation inversion operation

The vertical heat transport of internal solitary waves over the continental slope in the northern South China Sea

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Acta Oceanologica Sinica 2019年第3期38卷 36-44页

作者： Changrong liang Xiaodong shang Guiying Chen State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences University of Chinese Academy of Sciences

An integrated analysis of internal solitary wave(ISW) observations obtained from two moorings over the continental slope in the northern South China Sea(SCS) leads to an assessment of the vertical heat transport of the ISWs. The clusters of ISW packets are phase-locked to the fortnightly cycle of the semidiurnal tide. The ISWs appear during large semidiurnal tides, and there is a period of 5–6 d when no ISWs are observed. The effect of the ISWs on the continental slope heat budget is observed. The ISWs can modify a local temperature field in which the temperature in the upper layer can be changed by O(100) °C after the ISWs passed the mooring. Both ISWinduced diffusion and ISW-induced advection contribute to the temperature variation. The estimates imply an average vertical heat flux of 0.01 to 0.1 MW/m^2 in the ISWs in the upper 500 m of the water column. The vertical heat transport ranges from 0.56 to 2.83 GJ/m^2 with a mean value of 1.63 GJ/m^2. The observations suggest that the vertical heat transport is proportional to the maximum vertical displacement.

关键词： internal solitary wave vertical heat transport temperature variation diffusion advection vertical heat flux

Pre-formation Probability of ^5He Cluster in Pre-equilibrium Mechanism

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Communications in Theoretical Physics 2004年第4X期42卷 587-593页

作者： DUANJun-Feng YANYu-liang ZHANGJing-shang ChinaInstituteofAtomicEnergy P.O.Box275(41)Beijing102413China

The possibility of 5He cluster emission has been affirmed theoretically. In order to describe the emission probability of 5He cluster, the pre-formation probability of 5He cluster in pre-equilibrium emission process is needed to be established. In terms of Iwamoto-Harada model, the theoretical formula of pre-formation probability of 5He cluster including 1p shell nucleon in pre-equilibrium mechanism has been established and calculated. In the case of low incident energies, the configuration of [1, m] for 5He cluster is the dominant part in the nuclear reaction. The calculated results indicate that pre-formation probability of configuration [1, m] for the unstable 5He cluster is much smaller than those of d, t, 3He, and 4He, i.e. the light stable composite particles, which are consisted of only 1s shell nucleons. However, it is propitious to the emission of 5He from the point of view on threshold energies, since the binding energies of 5He are generally lower than that of 3He in compound nucleus. The corresponding model formula has been given in this paper for described pre-formation probability of 5He cluster in pre-equilibrium mechanism.

关键词：原子核物理核反应复合粒子辐射氦束辐射费米面