基于三角型模糊数理论的组合投资决策研究

基于三角型模糊数理论提出一种新的组合投资决策算法。首先应用三角型模糊数描述股票的价格变化过程,采用三角型模糊数的均值面积来表示相应价格信息;然后结合投资者的具体效用函数,并假设投资收益近似服从正态分布,获得其期望效用函数;最后根据Markowitz的均值-方差模型结论确定最优组合投资收益,从而确定投资者的最优组合投资比例。该算法简洁实用,便于操作,通过给出具体应用算例说明了该算法是行之有效的。     

对数效用函数的组合投资研究

研究了在证券组合投资中占重要地位的对数效用函数的组合投资问题。对数效用函数是一类非常典型且被投资者常用的风险厌恶型效用函数。应用无差异曲线法较好地解决了其最优组合投资比例的选择问题,并给出具体实例对文中所得结果加以验证。     

服从ARCH模型的风险资产定价模型

考虑服从ARCH模型的风险资产的定价问题,研究了投资者在具有二次效用函数下的最优投资组合问题。利用无套利原理给出了投资者在效用最大化条件下风险资产的定价问题,给出了最优投资组合的定价模型,并对不同形式下的定价公式进行了讨论。     

考虑损失厌恶的最优消费投资决策

行为金融文献表明,投资者效用既取决于消费,又取决于其持有的金融资产的价值变化.基于上述两点,研究了最优消费投资问题.将行为金融学中投资者损失厌恶这一重要心理纳入经典效用函数,给出了基于消费和风险资产价值变化的目标效用函数,建立了考虑投资者损失厌恶的最优消费投资模型,运用动态规划原理得到了最优消费和投资问题的值函数及最优消费投资策略.最后以一个两期最优消费投资算例说明该模型的应用.因考虑了投资者实际决策心理,建立的最优决策模型是对投资者实际决策行为的良好描述,由此得出的最优消费投资策略也可以更好地指导投资者消费投资行为.     

负指数效用函数最优组合的两种解法及其一致性

对投资组合中常用的负指数效用函数进行了研究,分别应用拉氏乘子法和无差异曲线法求解出该效用函数的最优组合投资比例,并验证了两种解法的一致性,即对该效用函数二者得出的解是相同的,并给出具体实例予以说明.     

带有随机因子的最优投资和消费问题(英文)

研究了一类证券市场中随机最优投资组合和消费模型,模型允许中间消费和贴现因子,投资者可以随机的改变交易策略。债券的价格服从确定性的常微分方程而股票的价格服从一个扩散过程,并且受随机因子的影响。当投资者的投资行为满足CRRA型效用函数,运用动态规划方法和幂变换的方法,通过求解相应的Hamilton-Jacobi-Bellman(HJB)方程,将值函数表示为相应的伪线性偏微分方程的解,并得到了最优投资组合及消费选择的显示解,并给出了最优投资组合策略。     

Heston模型的最优投资组合

在风险投资服从Heston模型的假设下,研究了幂效用函数的最优投资组合问题,利用动态规划方法通过HJB方程得到最优投资组合价值函数的显式解,并给出最优投资策略.     

摩擦市场的投资决策模型研究

根据摩擦市场的特点，建立了一个含有交易费、税收这两个摩擦因素及送股情况下的多目标规划模型，并利用效用函数将其转化为一个单目标模型。同时，针对投资者一般难以准确描述自己的效用函数这一事实，让投资者根据自己的效用偏好两两比较有效投资组合，然后利用Fabonacci法逐步逼近最优解，最后得到近似最优投资组合。     

Stein-Stein模型的最优投资组合

在风险资产服从S te in-S te in模型的假设下,研究了幂效用函数的最优投资组合问题.利用动态规划方法通过H JB方程得到最优投资组合价值函数的显式解,并给出最优投资策略.     

多个投资者的消费投资模型

讨论了单时期金融市场模型的最优投资组合问题,将多个投资者作为一个整体,得到了在同一个效用函数下,使总体期望消费效用达到最大的一般性结果.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that