西瓜的故事

正夜深了,乡村的田野一片寂静。看着村子里的灯光次第熄灭,刘爷爷在瓜地巡视了一圈后回家了。想着今年风调雨顺,丰收在望,他满意地点燃了一支烟。夜更深了,两个黑影摸进了瓜地。10分钟,20分钟……他们把一辆三轮车装满了。离开瓜地才走了几步,三轮车却罢工了——陷进了一个坑。     

聪明的矮子

从前,有七个兄弟,他们中有一个很矮小,但很聪明。有一天兄弟们杀了他的一头牛,吃完了,却一点也不留给他。“就给我牛皮吧。”矮子请求说,“我去卖了它。”兄弟们把牛皮给他,矮子出发了。路上,他看见一个洞,洞里住着老鼠,矮子就用牛皮盖住洞口,做成袋子一样,捉了几只老鼠。天黑了,他拿着这只牛皮袋爬到树上。不一会儿,几个商人带了一队骡子来了,骡子上装着许多货物,他们停在树下休息。半夜,矮子把老鼠抖落到骡子头上,骡子吓得都逃走了,商人也吓得魂不附体,嚎叫着各奔东西。矮子马上爬下树,拿了许多珍贵的东西回家去了。“你们宰了我的牛,宰得…     

杀手玩家

(上接6期)张轼只知道练功,不关心这甚嚣尘上的吸尘器传言。虽然笑傲江湖的滚动新闻已经把他列为重要新闻人物,可对此他却一无所知。现在他的法力系数被降下来了,内力也不行了,PK纪录都降成负的了。也就是说,以前杀了六千多人全白杀了,没人相信了,中国第一门户网站的第一高手不是他张轼了,而是别人了。肯定是网站出错闹故障了。以前也出现过这种情况,把他的记录给了别人,把别人的按到他头上,跟巫师讲了巫师才改过来。可是,这一回巫师却说改不过来,不但不肯改。而且怀疑他是骗子,想冒充断魂枪投机取巧。糟糕的是,不但他的PK纪录被改了,而且…     

动静结合 描绘美景

习作初稿阳春三月,果园里的果树陆续开花了,开出了五颜六色的花朵,有粉红的,雪白的,桃红色的……它们争奇斗艳。这时,果树的枝条上长出一个个的小芽儿。它们嫩绿嫩绿的。过了不久,小芽儿就长成了小叶片。它们翠绿翠绿的。过了一些日子,花儿凋谢了,果树上便挂满了小果子。修改指导习作片段按照时间的先后顺序,描写了果园里的果树开花、长叶、结果的景象,语句通顺,层次清     

厄尔尼诺和气候

南美洲国家秘鲁的太平洋沿岸在1925年3月发生了一场灾难。这个月份当地风后不是从东面吹来,而是来自西面。从赤道来的大量暖水代替了往常的冷水。于是,海里丰富的浮游生物不见了,吃浮游生物鱼类不见了,吃鱼的鸟类也不见了,秘鲁捕鱼量立刻大减。而且这个过去从不下雨的地方,现在却频繁地突降大量暴雨。大地苏醒了,披上了绿色盛装,河水也能流到海里了。然而不幸的是,与当地干旱气候相适应的粘土质建筑物却遭到了破坏,许多房屋酥软了,全市大约有1/3的     

改进的遗传算法求解TSP

阐述了一种针对TSP问题的改进遗传算法。引入了局部优化搜索算法。加快了算法的收敛速度。减轻了初值对结果的影响。加入了改进的OX交叉算法,在交叉中合理保留了优秀个体基因的排列顺序。利用精英复制保留了优秀基因。维持了种群个体数目稳定。提出了一种新的变异算法,有效避免了路径重复,减小了运算量,提高了运算速度。     

C语言教学改革实践与探索

为了全面提高高职教学质量,各高职院校积极开展教学改革。本文主要介绍了在教学过程中采用了模块化教学方法进行教学改革,增强了学生的学习兴趣,提高了教学质量,加强了学生的实践动手能力。对实施过程中存在的问题进行了分析,提出了进一步解决的想法。     

大白鹅擦锅盖

小黑猪的铝锅盖脏了,上面全是油渍。他自己怎么擦也擦不干净,就登出告示,谁能用最简单的方法又快又好地擦净他的锅盖,必有重赏。重赏之下有勇夫。平时从不爱搞卫生的大黄狗最先来到,用了小半袋洗衣粉,倒上去就使劲擦,油渍也擦去了一些,可小黑猪说这样擦太费钱了。老白猫赶来了,说用去污剂肯定效果好。他就用新上市的去污剂使劲擦了起来,小黑猪问他成本是多少,他说比洗衣粉高一些。小黑猪听了摇了摇头。大黄马、小花牛、老麻鸭等都使出了自己的绝招儿,小黑猪也都不怎么满意。最后,大白鹅一摆一摆地走来了。他端来一些米汤,大家见了都笑了:“…     

哈欠围脖(外一则)

正小青蛙,打了好多哈欠圈。有圆的,有方的,有三角形的。小青蛙,打了好多有颜色的哈欠圈。有红的,有黄的,有蓝的,有绿的,有粉的。小青蛙把哈欠圈收集起来,编结成一个围脖。大青蛙失眠了,小青蛙就把围脖送给了大青蛙。大青蛙刚一围上,就哈欠连天,困极子。第二场雪时,雪人给椅子铺了一张白椅垫,又厚又软,可小兔一坐上去,椅垫就瘪了。第二场雪时,雪人给圆圆的石桌涂了香浓的奶油,引人即刻想吃一口,可小兔刚吃了一口,就把牙冰疼了。第二场雪时,雪人在地上准备了一张白画布,月亮、竹叶、     

春雨

正冬天过去了,春姑娘悄悄地走来了,她还带来了她的好朋友——春雨。"春雨贵如油",她们一来,大地变得可热闹了。春雨首先来到高山上看望松树伯伯。她把松树伯伯身上落了一冬天的灰尘都洗掉了,松树伯伯的叶子变得更加苍翠了.好像换上了一件崭新的衣裳。松树伯伯高兴地对春雨说:"谢谢你,春雨姑娘,你帮我洗了澡,我自己都觉得年轻了许多。"春雨笑说:"不用谢,您坚强勇敢,不怕冷不怕冻,在寒冷的冬天还保持着绿色,让人们看到了生机。看到了希望。"     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to