A Layer-Stripping Method for 3D Near-Surface Velocity Model Building Using Seismic First-Arrival Times

In order to improve the efficiency of 3D near-surface velocity model building, we develop a layer-stripping method using seismic first-arrival times. The velocity model within a Common Mid-Point (CMP) ...     

弱智儿童的脑机制及教育启示探析

弱智儿童的脑机制是我国特殊教育界尚未探讨的一个领域。从智力、弱智和学习的本质出发,探讨了弱智儿童脑发育的机制和脑活动机制,认为弱智儿童脑发育的正常机制因为先天、后天的遗传异常或损伤遭到了破坏,由此导致了神经系统的传导失能,并表现为神经环路的形成困难、传导的信息堵塞和消失这些主要的神经活动特点。提出了干预或教育弱智儿童的三大措施,包括食物或物质干预、文化给予以及感官训练与文化、言语的结合。     

An Economic Model-Based Matching Approach Between Buyers and Sellers Through a Broker in an Open E-Marketplace

A broker in an open e-marketplace enables buyers and sellers to do business with each other. Although a broker plays an important role in e-marketplaces, theory and guidelines for matching between buyers and sellers in multi-attribute exchanges are limited. Therefore, a challenge for a broker’s responsibility is how to maximize a buyer’s total satisfaction degree as its goals under the consideration of trade-off between a buyer’s buying quantity and price paid to a seller, and other attributes. To solve this challenge, this paper proposes an economic model-based matching approach between a buyer’s requirements and a seller’s offers. The major contributions of this paper are that (i) a broker can model a seller’s price policy as per a buyer’s buying quantity through communication between a broker and a seller; (ii) due to each buyer’s different quantity demand, a broker models a buyer’s satisfaction degree as per a buyer’s buying quantity based on communication between a broker and a buyer; and (iii) to carry out a broker’s matching processes, an objective function and a set of constraints are generated to help a broker to maximize a buyer’s total satisfaction degree. Experimental results demonstrate the good performance of the proposed approach.     

Hierarchical Community Detection Based on Partial Matrix Convergence Using Random Walks

Random walks are a standard tool for modeling the spreading process in social and biological systems.But in the face of large-scale networks,to achieve convergence,iterative calculation of the transition matrix in random walk methods consumes a lot of time.In this paper,we propose a three-stage hierarchical community detection algorithm based on Partial Matrix Approximation Convergence(PMAC) using random walks.First,this algorithm identifies the initial core nodes in a network by classical measurement and then utilizes the error function of the partial transition matrix convergence of the core nodes to determine the number of random walks steps.As such,the PMAC of the core nodes replaces the final convergence of all the nodes in the whole matrix.Finally,based on the approximation convergence transition matrix,we cluster the communities around core nodes and use a closeness index to merge two communities.By recursively repeating the process,a dendrogram of the communities is eventually constructed.We validated the performance of the PMAC by comparing its results with those of two representative methods for three real-world networks with different scales.     

乡村振兴绩效评价:意义、维度与路径

2018年,中共中央、国务院印发《中国乡村振兴战略规划(2018-2022年)》,全面部署和布局乡村振兴战略.文章基于政府绩效评价的理念和方法,构建乡村振兴绩效评价指标体系,明确评价维度,为实现乡村振兴、城乡融合发展提供价值导向、度量体系和动力工具.该评价维度包涵资源投入、过程监管、目标实现情况和社会满意度四个方面.文章指出,相关单位以绩效评价推进乡村振兴时应注重顶层设计,强化部门协同,构建评价体系,引入第三方评价主体,凸显农民获得感.     

等候区手术患者家属的心理影响因素及干预措施

目的:探讨等候区手术患者家属的心理影响因素及其干预措施.方法:通过临床护理实践及查阅相关文献进行总结分析.结果:影响因素及其干预措施包括详解病情及手术风险性;对手术环境及术中情况的告知;完善急诊手术患者家属心理干预;根据不同文化水平进行健康宣教;尽量以病情为主,设计最经济有效的治疗方案;提高医护人员从业技能及道德品质.结论:对等候区手术患者家属进行积极有效的心理干预,可很大程度上减轻患者家属的焦虑程度,缓和医患关系,一定程度上提升了医疗质量.     

带有白噪声的Berger方程随机吸引子

考虑带有白噪声的Berger方程解的随机渐近性行为, 用渐近先验估计技术和算子分解方法, 通过引入同构映射构造等价过程, 证明随机吸引子在(H²(U)∩H¹₀(U))×L²(U)中的存在性.     

数字量子模拟已经应用到两费米子体系了（英文）

In a recent work,a group of researchers led by Gui-Lu Long of Tsinghua University proposed a digital quantum simulation algorithm for the dynamics of interacting quantum systems in real space.They experimentally implemented the algorithm to simulate the dynamics of two interacting fermions using a nuclear magnetic resonance(NMR)setup[1].     

Modeling eBay price using stochastic differential equations

Online auctions have become increasingly popular in recent years. There is a growing body of research on this topic, whereas modeling online auction price curves constitutes one of the most interesting problems. Most research treats price curves as deterministic functions, which ignores the random effects of external and internal factors. To account for the randomness, a more realistic model using stochastic differential equations is proposed in this paper. The online auction price is modeled by a stochastic differential equation in which the deterministic part is equivalent to the second‐order differential equation model proposed in Wang et al. (Journal of the American Statistical Association, 2008, 103, 1100–1118). The model also includes a component representing the measurement errors. Explicit expressions for the likelihood function are also obtained, from which statistical inference can be conducted. Forecast accuracy of the proposed model is compared with the ODE (ordinary differential equation) approach. Simulation results show that the proposed model performs better.