A Parallel Hill Climbing Algorithm for Pushing Dependent Data in Clients–Providers–Servers Systems

The up-link bandwidth in satellite networks and in advanced traffic wireless information system is very limited. A server broadcasts data files provided by different independent providers and accessed by many clients in a round-robin manner. The clients who access these files may have different patterns of access. Some clients may wish to access several files in any order (AND), some wish to access one out of several files (OR), and some clients may access a second file only after accessing another file (IMPLY). The goal of the server is to order the files in a way that minimizes the access time of the clients given some a priori knowledge of their access patterns. An appropriate clients–servers model was recently proposed by Bay-Noy, Naor and Schieber. They formulated three separate problems and proposed an algorithm that evaluates certain number of random permutations and chooses the one whose access time is minimized. In this paper, we formulate a combined AOI (AND-OR-IMPLY) problem, and propose to apply a parallel hill climbing algorithm (to each of the four problems), which begins from certain number of random permutations, and then applies hill climbing technique on each of them until there is no more improvement. The evaluation time of neighboring permutations generated in hill climbing process is optimized, so that it requires O(n) time per permutation instead of O(n ²) time required for evaluating access time of a random permutation, where n is the number of files the server broadcasts. Experiments indicate that the parallel hill climbing algorithm is O(n) times faster that random permutations method, both in terms of time needed to evaluate the same number of permutations, and time needed to provide a high quality solution. Thus the improvement is significant for broadcasting large number of files.     

Perceiving Virtual Geographical Slant: Action Influences Perception.

In 4 experiments, the authors varied the extent and nature of participant movement in a virtual environment to examine the influence of action on estimates of geographical slant. Previous studies showed that people consciously overestimate hill slant but can still accurately guide an action toward the hill (D. R. Proffitt, M. Bhalla, R. Gossweiler, & J. Midgett, 1995). Related studies suggest that one's potential to act may influence perception of slant and that distinct representations may independently inform perceptual and motoric responses. The authors found that in all conditions, perceptual judgments were overestimated and motoric adjustments were more accurate. The virtual environment allowed manipulation of the effort required to walk up simulated hills. Walking with the effort appropriate to the visual slant led to increased perceptual overestimation of slant compared with active walking with the effort appropriate to level ground, while visually guided actions remained accurate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

大港油田千米桥潜山油气运移期次研究

对大港油田千米桥潜山奥陶系石灰岩中包裹体的特征及均一温度进行了分析，发现其均一温度可分为3期。根据对包裹体的特征和均一温度分布的分析，认为千米桥潜山发生了3期油气运聚，第一期油气运移发生于距今35.1～15.5 Ma之间，即始于沙河阶组一段沉积早期，止于馆陶期末，运移期间埋深变化于2197.18～2901.41 m；第二期油气运移发生于距今9.1～6.0 Ma之间，即始于明化镇组沉积早中期，止于明化镇组沉积中期；第三期油气运移发生于距今3.5 Ma以后，即明化镇组沉积晚期以后才发生大规模的天然气运移。     

古潜山探井综合堵漏技术

分析了古潜山探井在钻井中遇到的井漏类型。根据井漏情况总结了一套与其相适应的综合堵漏方法。应用在古潜山探井钻井中取得了成功。对古潜山钻井井漏处理具有一定的指导意义。     

胜利油区车古20潜山储层岩石物理特征

胜利油区车古20潜山在下古生界碳酸盐岩地层中发现商业油气流,为了揭示该潜山油藏分布规律,以岩心分析、测试资料研究为基础,充分利用测井资料对潜山储层岩石物理特征进行系统研究:应用测井资料,采用模糊数学方法,建立识别碳酸盐岩储层岩性模型,划分储集岩和非储集岩;利用大岩样校正小岩样,与测井解释有效孔隙度建立关系,求取有效孔隙度;利用双侧向电阻率,在识别裂缝类型基础上,建立裂缝孔隙度解释模型;根据不同裂缝类型,利用双侧向测井资料,建立流体饱和度解释模型;综合上述情况,制定有效厚度划分标准.应用实测资料对所建模型进行可行性评价,达到较高的符合一致性,取得理想效果.     

一处浅丘基地的记忆——四川美术学院虎溪校园地志解读

从地志的角度对一处浅丘基地——位于重庆市沙坪坝区虎溪镇的四川美术学院新校区建设用地——进行了深度解读,通过对“场地记忆”的关注发现了305m标高、原有山路、民居、植被、山顶、灌溉渠在未来校园中的意义,阐述了对山地的地形完整性、方向感、建筑群选址、地貌肌理以及山地人文记忆的理解,探索了基于场地记忆而采取的设计和建造对策。     

超长不规则地下室深基坑和底板施工技术

针对江门五邑锦绣豪庭高层住宅地下室超长、不规则、高岭土质的工程特点,重点阐述了在高岭土地质环境下,超长、不规则、深基坑开挖与底板混凝土连续浇筑的施工技术,积累了工程施工经验。     

冀中坳陷廊固凹陷河西务构造带潜山储集层特征

对渤海湾盆地冀中坳陷廊固凹陷河西务构造带潜山储集层的岩心及地面露头进行了综合研究.潜山储集层的岩性主要是碳酸盐岩,储集空间包括溶孔、溶洞、裂缝和基岩微观孔隙,形成孔-洞型、裂缝型、缝-洞型和孔-洞-缝复合型的碳酸盐岩储集层.区内多期次的古岩溶作用是储集层形成的重要因素之一,古岩溶作用主要发生于沿潜山不整合面的风化淋滤带、水平潜流带、断层裂隙带及顺层层面,形成相应的溶蚀孔洞型储集层.由构造运动所形成的裂缝不仅增加了储集层的孔隙度,还极大地改善了孔洞的连通性,提高了储集层的渗透性能.但不同岩性、不同构造部位储集层的发育程度不同:白云岩类储集层好于灰岩类储集层,无石炭-二叠系覆盖区的储集层好于有石炭-二叠系覆盖区,断层发育区内储集层好干断层不发育区.河西务构造带西南端潜山储集层发育,是有利的油气勘探区块.图4表4参14     

华北油田深潜山欠平衡钻井技术

综合欠平衡钻井技术自身特点和华北油田的地层特性,通过对欠平衡地层优选、井身结构优化、钻头对比优选、钻井液体系优选、钻井液密度及井口控制压力准确计算等手段,在冀中探区10余口井的钻探过程中成功应用了欠平衡钻井技术,取得了明显的效果:潜山欠平衡段机械钻速较邻井同井段提高2～2.5倍,欠平衡井段均未发生漏失,钻井过程中油气显示活跃,长6井中途测试日产油108 m3,日产气2376 m3,文古3井日产油302.6 m3,日产气9.8×104m3.深井欠平衡钻井的成功实施为华北油田提高油气藏综合开发效益提供了一条新的技术路线,也为今后该技术的推广应用积累了经验.     

冀中坳陷古潜山类型及油气成藏

在总结前人的潜山分类基础上,从形成潜山的地质背景和成因出发,把冀中坳陷潜山分为地貌潜山和构造潜山两大类。进一步又可分为6小类。冀中坳陷古潜山是在特定的构造背景下形成的,空间上可组合成饶阳式和霸县式两种模式。不同类型的潜山具有不同的分布规律和成藏条件,发育单断式、断阶式、斜坡式和侵蚀型4种类型的潜山油气藏,其中单断式最发育,断阶武和斜坡式次之。侵蚀型少见。