A new methodology for Bayesian history matching using parallel interacting Markov chain Monte Carlo

This paper presents an innovative application of a new class of parallel interacting Markov chains Monte Carlo to solve the Bayesian history matching (BHM) problem. BHM consists of sampling a posterior distribution given by the Bayesian theorem. Markov chain Monte Carlo (MCMC) is well suited for sampling, in principle, any type of distribution; however the number of iteration required by the traditional single-chain MCMC can be prohibitive in BHM applications. Furthermore, history matching is typically a highly nonlinear inverse problem, which leads in very complex posterior distributions, characterized by many separated modes. Therefore, single chain can be trapped into a local mode. Parallel interacting chains is an interesting way to overcome this problem, as shown in this paper. In addition, we presented new approaches to define starting points for the parallel chains. For validation purposes, the proposed methodology is firstly applied in a simple but challenging cross section reservoir model with many modes in the posterior distribution. Afterwards, the application to a realistic case integrated to geostatistical modelling is also presented. The results showed that the combination of parallel interacting chain with the capabilities of distributed computing commonly available nowadays is very promising to solve the BHM problem.     

基于流变特性的含铝凝胶燃料制备工艺研究

为提升液固燃料的结构稳定性,以无机纳米颗粒为凝胶剂制备了环氧丙烷基凝胶基质,在基质中引入微米铝粉,得到含铝凝胶燃料。通过测定凝胶基质的弹性模量G′₀和线性区范围γ_c,分析了超声和热处理对纳米颗粒成胶的影响。针对不同含铝量的凝胶燃料,在不同剪切速率（0.1～2 000.0 s^-1）下,进行了旋转剪切测试,并研究了剪切历史对燃料流动曲线的影响。结果表明,超声和加热对纳米颗粒的成胶效果皆有促进作用。低剪切速率（γ<100 s^-1）下,剪切历史会使得凝胶体系黏度增高;超过100 s^-1后,黏度较无剪切历史的样品低。流动曲线显示,含铝凝胶燃料在100 s-1附近出现增稠现象,而更高的剪切速率直接导致凝胶结构在短时间内出现不可逆破坏,致使黏度迅速降低。     

浅析医院信息系统的发展及未来

文章首先阐述了医院信息系统(Hospital Information System,HIS)的基本概念,回顾了我国医院信息系统的发展历史,从投资规模、标准化、规范化体系等几个方面分析了我国现有HIS存在的问题,指出了未来我国医院信息系统的发展趋势是逐步完善信息标准化,HIS的发展将以患者为中心,远程医疗系统不断完善,以及充分利用数据资源为医院发展提供决策依据。     

Innovations in Individual Feature History Management—The Significance of Feature-based Temporal Model

A feature relies on three dimensions (space, theme, and time) for its representation. Even though spatiotemporal models have been proposed, they have principally focused on the spatial changes of a feature. In this paper, a feature-based temporal model is proposed to represent the changes of both space and theme independently. The proposed model modifies the ISO’s temporal schema and adds new explicit temporal relationship structure that stores temporal topological relationship with the ISO’s temporal primitives of a feature in order to keep track feature history. The explicit temporal relationship can enhance query performance on feature history by removing topological comparison during query process. Further, a prototype system has been developed to test a proposed feature-based temporal model by querying land parcel history in Athens, Georgia. The result of temporal query on individual feature history shows the efficiency of the explicit temporal relationship structure.

略论江南地区漆文化历史发展

江南地区漆文化有着悠久的历史,无论是漆工艺的发展,还是功能内涵由实用向精神、审美的多元拓展,均完整地呈现了我国漆文化的演进。因此,研究江南地区漆文化历史对于传承我国传统漆文化有着重要意义。     

古琉璃与现代玻璃艺术的继承与创新——从中国玻璃艺术史的角度谈

论文首先对中国古玻璃①艺术形式进行分析,从宏观上对中国古代玻璃技术的发展进行整体阐述,指出古代中国的玻璃行业发展缓慢的原因和现代玻璃艺术的出现与大发展。本文着重于从玻璃艺术工艺入手,解析历史中的工艺形态、技术应用现象,结合其工艺自身的特点和艺术的形式规律,对传统工艺的再开发,挖掘其潜力为今天服务。现代的工艺形式是基于古老的传统技术手法之上的,是传统工艺的延续和变革。     

实时数据库事务的正确性及实现算法

实时数据库系统中事务可以有定时限制（典型地为截止期）,事务超过截止期可能给系统带来灾难性后果,事务不光要满足数据库的完整性与一致性,而且要满足在时间上的正确性以及事务之间在结构上的正确性,传统的事务处理方法仅着眼于事务存取数据库的正确性,对于时间正确性与结构正确性无能为力,详细讲座了实时事务的正确性,包含结果正确性、时间正确性、行为正确性及结构正确性,已有的研究成果中大多用不央的算法及策略来保证不同的正确性要求;给出了保证实时事务正确性的一个统一的图论算法。     

我国污水处理回用发展历程及特点

通过对我国城市污水处理回用发展历程的回顾,从回用量、回用对象、回用工艺、回用水价几个方面进行比较分析,揭示出我国城市污水处理回用的主要特点,根据我国在城市污水处理回用工作中存在体制、制度、工艺、水价等方面的问题,提高全国城市污水处理回用率,从体制建设、法规体系、工艺选取、监督管理等几个方面提出今后工作建议,为水利部提出的"三条红线"管理做好技术支撑。     

历史维度下的河西走廊水利问题研究

社会建设和生态文明建设中,历史维度是不可或缺的一环,流域管理亦然。通过对河西走廊近代水资源开发利用历史的回顾,分析了甘肃省河西走廊地区石羊河、疏勒河及讨赖河流域的水资源开发利用、社会经济发展和流域管理的演变,重点探讨了河西走廊地区历史上形成的"以时分水"的时间水权制度的运行情况、人类活动影响下流域水循环特征变化导致时间水权制度失效的机理,以及讨赖河流域传统分水模式与现代水利制度衔接的现实需求与可能方式。研究认为,在历史维度下进行流域管理问题研究,对于深入认识河西走廊水环境演化规律、深刻理解水资源开发利用管理问题的现实内涵、科学制定传统水资源管理与现实发展要求衔接的可行方案具有重要意义。     

Seismic response of concrete gravity dam reinforced with FRP sheets on dam surface

This paper aims at exploring the effects of anti-seismic reinforcement with the fiber-reinforced polymer （FRP） material bonded to the dam surface in dam engineering. Time-history analysis was performed to simulate the seismic failure process of a gravity dam that was assumed to be reinforced at the locations of slope discontinuity at the downstream surface, part of the upstream face, and the dam heel. A damage model considering the influence of concrete heterogeneity was used to model the nonlinearity of concrete. A bond-slip model was applied to the interface between FRP and concrete, and the reinforcement mechanism was analyzed through the bond stress and the stress in FRP. The results of the crack pattern, displacement, and acceleration of the reinforced dam were compared with those of the original one. It is shown that FRP, as a reinforcement material, postpones the occurrence of cracks and slows the crack propagation, and that cracks emanating from the upstream surface and downstream surface are not connected, meaning that the reinforced dam can retain water-impounding function when subjected to the earthquake. Anti-seismic reinforcement with FRP is therefore beneficial to improving the seismic resistant capability of concrete dams.