锚固地梁技术在人工边坡治理中的应用研究

峡口码头高切坡,处于硬软岩性的交接部位,岩体中裂隙发育,多为层状结构和碎裂结构,在切坡初期,常产生规模不等的滑移破坏。基于小变形的假设和有限元分析基础上,确定工程治理措施,是紧密结合工程实践的重要课题。     

加强实验教学,培养学生实验技能和综合素质

为了提高学生的动手能力,启迪学生严谨科学的思维方法,培养学生的创新意识和实践能力,我们在植物生理生化实验教学中进行了努力的探索。通过加强实验教学,学生具备了更强的科学研究的实验技能,学生的综合素质也有较大的提高,教学效果得到社会、学校和学生的认同,较好地完成了实验教学的主要任务。     

干熄焦锅炉爆管的原因及预防措施

结合梅山钢铁公司能源公司1^#于熄焦锅炉的运行情况及国内于熄焦锅炉爆管的原因进行技术分析，得出爆管的主要原因，并制定预防措施，确保CDQ锅炉的安全稳定运行。     

一类非线性常微分方程边值问题解的存在性

采用三层加密技术,即在用户IE客户端,使用VB脚本对用户提交的信息进行第1层加密;在网站服务器端,使用ASP函数进行第2层加密;在数据库服务器端,使用SQL自定义函数,对进入数据库的信息进行第3层加密,开发了《上海电视大学教务管理系统分校版》管理软件,并进行了实际应用。     

石油及液体石油产品静态计量技术

介绍了石油静态计量基础知识,包括物理特性、大罐的标定、温度、液位、含水的测量方法,最后给出了标准计算顺序。     

人民币汇率管理技术研究

新的人民币汇率形成机制对汇率管理提出了更高的技术要求。人民于汇率管理技术作为一种重要的生产力,为人民币汇率管理提供了重要的操作技巧和技术支持。创新和发展人民币汇率管理技术,有利于进一步提高人民币汇率管理效率和外汇资源配置效率。人民币汇率管理技术的变近大致经历了萌芽阶段、起步阶段、徘徊阶段和快速发展4个时期;人民币汇率管理技术的创新内容包括人民币汇率机制管理技术、弹性管理技术、风险管理技术和信息管理技术等;人民币汇率管理技术的未来发展方向应由“原始型、初级型、封闭型、粗放型、僵化型”向“现代型、市场型、开放型、集约型、创新型”转变。同时,针对人民币汇率管理技术发展中的制约因素,还要注意发展策略的选择,如培育有效的外汇专场主体．加强汇率基础设施建设,营造汇率生态环境,培养金融技术人才等。     

Error analysis of finite difference and Markov chain approximations for option pricing

Mijatovi? and Pistorius proposed an efficient Markov chain approximation method for pricing European and barrier options in general one‐dimensional Markovian models. However, sharp convergence rates of this method for realistic financial payoffs, which are nonsmooth, are rarely available. In this paper, we solve this problem for general one‐dimensional diffusion models, which play a fundamental role in financial applications. For such models, the Markov chain approximation method is equivalent to the method of lines using the central difference. Our analysis is based on the spectral representation of the exact solution and the approximate solution. By establishing the convergence rate for the eigenvalues and the eigenfunctions, we obtain sharp convergence rates for the transition density and the price of options with nonsmooth payoffs. In particular, we show that for call‐/put‐type payoffs, convergence is second order, while for digital‐type payoffs, convergence is generally only first order. Furthermore, we provide theoretical justification for two well‐known smoothing techniques that can restore second‐order convergence for digital‐type payoffs and explain oscillations observed in the convergence for options with nonsmooth payoffs. As an extension, we also establish sharp convergence rates for European options for a rich class of Markovian jump models constructed from diffusions via subordination. The theoretical estimates are confirmed using numerical examples.     

Estimation bias in choice models with last choice feedback

The study compares two estimation methods for choice models with last choice feedback, using simulated and real data. The first method ignores the impact of unobserved heterogeneity on observed choices via presample choices, while the second method approximates this impact by a stochastic relationship. In panels with less than 10 choices per panelist, the first method overstates the impact of last choice on current choice and understates the impact of intrinsic preferences (i.e., brand intercepts). The second method performs significantly better than the first method. Under both methods, an increase in the number of heterogeneous coefficients in the model tends to increase the bias in the estimates. The largest bias occurs when lagged choice coefficients are heterogeneous.     

Optimal high-frequency trading with limit and market orders

We propose a framework for studying optimal market-making policies in a limit order book (LOB). The bid–ask spread of the LOB is modeled by a tick-valued continuous-time Markov chain. We consider a small agent who continuously submits limit buy/sell orders at best bid/ask quotes, and may also set limit orders at best bid (resp. ask) plus (resp. minus) a tick for obtaining execution order priority, which is a crucial issue in high-frequency trading. The agent faces an execution risk since her limit orders are executed only when they meet counterpart market orders. She is also subject to inventory risk due to price volatility when holding the risky asset. The agent can then also choose to trade with market orders, and therefore obtain immediate execution, but at a less favorable price. The objective of the market maker is to maximize her expected utility from revenue over a short-term horizon by a trade-off between limit and market orders, while controlling her inventory position. This is formulated as a mixed regime switching regular/impulse control problem that we characterize in terms of a quasi-variational system by dynamic programming methods. Calibration procedures are derived for estimating the transition matrix and intensity parameters for the spread and for Cox processes modelling the execution of limit orders. We provide an explicit backward splitting scheme for solving the problem and show how it can be reduced to a system of simple equations involving only the inventory and spread variables. Several computational tests are performed both on simulated and real data, and illustrate the impact and profit when considering execution priority in limit orders and market orders.     

我国出口企业自主创新能力不足的原因解析

我国成为世界第三大贸易国是由外资企业推动的。本文认为。我国需要内、外资企业两方面的支持，才能由制造业大国走向制造业强国；内资企业存在的主要问题在于技术引进了，吸收消化能力却未同步提高，缺乏自主知识产权导致高新技术产品出口效益低下等。