2003年十大科技趋势

1.无线技术:Wi—Fi大行其道2003年,一些主要的跨国无线运营商将为用户提供高速无线局域网(WLAN)接入服务,又名Wi—Fi接入服务,它将使得用户通过计算机、掌上电脑或是手机实现无线连网。但是,就短期而言,Wi—Fi技术的发展可能会对3G技术产生一定的负面影响,WLAN的网络速度将是3G的20倍,成本仅是后者五千分之一。分析人士指出,目前用户对无线网络的需求日益增加,Wi—Fi技术正好填补了3G的不足,但是无线网络服务的收益不会让运营商特别高兴,因为竞争日趋激烈,导致服务费不可能利润丰厚。     

运营级Wi—Fi网络中的QoS研究

从Wi—Fi技术被广泛应用于语音、多媒体传输等的角度，引出Wi—Fi技术中对高速率传输业务的QoS保障机制——WMM（Wi—Fi Multimedia），通过对WMM的测试，以及从运营的角度对Wi—Fi网络应用和需求进行分析，提出Wi—Fi网络QoS保障需要解决的几个问题和建议，并对Wi—Fi技术的发展进行了展望。     

TD—SCDMA与Wi—Fi融合方案探析

在TD—SCDMA建设初期,网络不可避免地存在容量和覆盖不足的问题．为了弥补TD—SCDMA在一些热点区域高速数据业务的覆盖和容量的不足,结合解决Wj—Fj用户对于网络广覆盖和移动性的需求,从分析TD—SCDMA和Wj—Fj融合的必要性出发,基于TD—SCDMA和Wi—Fi的两种网络融合模式各自的优缺点,提出TD—SCDMA和Wi—Fi融合的典型核心网组网方案和无线网建设方案．     

铮铮脊骨发明人生——访上海恒大胆机有限公司董事长、中国发明协会会员薛伟达

抢时间发展中国名牌胆机逼我们成为胆机的世界顶尖人才围绕胆机世界市场的运转采访之际,薛伟达正在忙碌地准备着将于11月份到北京人民大会堂参加“第一届中国发明家论坛”的组团工作,电话不停,谈话不时被打断。薛伟达告诉记者,偌大一个上海,作为独立发明人受到此次论坛邀请的,是     

你所连接上的WIFI是否安全?

<正>在互联网的大浪潮下涌现出许多新名词,其中Wi Fi作为一种允许电子设备连接到一个无线局域网的技术,被人们日渐熟知。此外,Wi Fi因其便捷通用的特性,也受到了年轻人的热烈推崇,在这个Wi Fi慢慢普及的时代,蹭Wi Fi成为了一项基本"生存技能"。但在享受Wi Fi带来便利的同时,人们也缺乏相应Wi Fi上网的安全防范意识,在一些大型商场、公共设施上,市民都可以很顺畅地使用无线网     

移动存储设备资源管理器

发明背量： 虽然现在计算机已经相当普及,而且在朝着小型化方向发展,但还并不是随时随地都能使用,虽然3G、Wi—Fi等无线网络为资源共享提供了方便,但是传输速度还不尽如人意.     

一类非线性奇异积分方程的迭代解法

研究一类不含参数 λ的非线性奇异积分方程 u=Fu,并给出它的一种迭代解法 ,其中非线性算子 F可以分解为有限个算子之和 F= mi=1 Fi,且算子 Fi具有幂的性质 :Fi( au) =a Ki Fi( u) ( Ki<1 ) .     

基于ZigBee和WiFi的油田无线监测系统设计

针对油田数据的采集监测及远程应用的需求,提出了一种用于油田的无线网络系统。该系统将Zig Bee技术与Wi Fi技术相结合,实现监测信息的无线传输;传感节点以XBee PRO S2B为主控芯片,通过电量、压力、载荷、位移、温度传感器实时采集项目数据,采集到的数据通过Zig Bee网络传至Zig Bee-Wi Fi中继转换器转送至Wi Fi网络,转换器既作为Zig Bee网络的协调器,又作为Wi Fi网络的节点;通过Zig Bee网络与Wi Fi网络的结合,数据可以在移动手持设备上显示并并进行分析。系统实现了油田的远程监测、2种通信技术的转换及低功耗、高速率数据传输,使油田数据的采集更加方便、灵活。     

点灯上网:可见光通信技术展望

19世纪,美国科学家爱迪生用电灯为人类带来光明;20世纪,澳洲技术宅John O’Sullivan用Wi Fi将人们接入网络;而时至21世纪,德国物理学家哈拉尔德·哈斯让"无需Wi Fi,点灯上网"的可见光通信由梦想照进了现实——作为Wi Fi的"挑战者",它诞生之日即被人们亲切昵称为"Li Fi",而作为新兴的无线通信技术,其究竟能否为无线网络传输带来革命性改变、进而催生新一轮产业发展机遇?     

具有反馈的批到达离开门限与减1服务轮询系统

考虑了具有贝努利反馈的批到达服务轮询系统：对于离开门眼服务规则下的轮询系统，得到了Fi 1(Z1，Z2，…，ZN)与Fi(Z1，Z2，…，ZN)的关系，各站轮询时刻的平均队长；服务器的轮询周期、服务器每次在各站的停留时间、访问间隔时间。对于减1服务规则下轮询系统而言，推导了Fi 1(Z1，Z2，…，ZN)与Fi(Z1，Z2，…，ZN)与的关系以及服务器每次在各站的停留时间。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.