首都崛起座图书城

在北京,与闻名全国的中关村电子一条街相邻,一个悄然而起的现代化建筑群——中国海淀图书城(一期工程)近日全面竣工。它作为国内第一个大型固定的图书集散市场,4月下旬开业后,将由首批进驻的出版单位直接向社会长期提供数量充足、品种齐全、面世最早的科技文化类图书。这个图书城的出现,标志着我国在探索广开图书发行渠道、改善群众购书环境方面的一个突破。 时代的需求 伴随改革开放以来的经济振兴。

漫谈藏族礼仪文化

藏族人民是个重礼仪的民族。他们在各种社会交往中,处处以礼待人,忌讳不雅之习。同时他们的日常礼仪与所信仰的宗教有着密切的关系。常见的礼仪有以下几个方面。 一、礼尚往来 赠送哈达是藏族人民较为普遍的一种礼节。哈达之意:“是神的光辉、萦绕的祥云。是神灵的化身。它表示与神同在,幸福无边,吉祥如意”。主要的种类有:特等内库哈达;头等阿喜哈达;二等素喜哈达;三等素达哈达等。哈达有丝织和白麻织的两种。颜色为:红、白、黄、蓝色。一般长度二三米不定。在精织的丝绸哈达上,织有八宝吉祥图、莲花云座图等。现在藏族人民普遍喜用白色的麻织哈达。因为白色象征着纯洁和吉祥。 向对方馈赠哈达时,必须用双手捧献。

A 3-D Polarization Quadrature Amplitude Modulation Method and Constellation Mapping

As a new three-dimensional(3-D)modulation,Polarization Quadrature Amplitude Modulation(PQAM) can be regarded as the combination of Pulse amplitude modulation(PAM) and Quadrature Amplitude Modulation(QAM) Modulation.It can better improve the digital communication efficiency and reduce the Symbol error rate(SER) of the system than one-dimensional or two-dimensional modulation scheme.How to design a feasible constellation is the most concerned problem of PQAM currently.This paper first studies the relationship between the SER theoretical value of PQAM and the distribution of M and N,proposes a new M,N allocation scheme.Secondly,a new and straightforward design method of constructing higher-level 3-D signal constellations,which can be matched with the PQAM,and the constellation can divided into three different structures according to the ary for PQAM.Finally,the simulation results show that:in PQAM system,the modulation scheme and the constellation mapping scheme are proposed in this paper which can effectively reduce the system SER and improve the anti-noise performance of the system.

3D graphical visualization of the genetic architectures underlying complex traits in multiple environments

An approach for generating interactive 3D graphical visualization of the genetic architectures of complex traits in multiple environments is described. 3D graphical visualization is utilized for making improvements on traditional plots in quan- titative trait locus (QTL) mapping analysis. Interactive 3D graphical visualization for abstract expression of QTL, epistasis and their environmental interactions for experimental populations was developed in framework of user-friendly software QTLNetwork (http://ibi.zju.edu.cn/software/qtlnetwork). Novel definition of graphical meta system and computation of virtual coordinates are used to achieve explicit but meaningful visualization. Interactive 3D graphical visualization for QTL analysis provides geneticists and breeders a powerful and easy-to-use tool to analyze and publish their research results.

Cooperative DVB-SH Satellite Broadcasting Systems with Rotated Signal Constellations

In this paper,we study the advantages of cooperation in broadcasting systems from a geosynchronous earth orbit(GEO)satellite to mobile terminals(MTs),achieved through a terrestrial complementary ground station(CGS) with fixed installment,which acts as a relay.Moreover and in the context of the digital video broadcasting-satellite-to-handheld(DVB-SH) standard,the performance improvements offered by the rotated constellations method are investigated,where prior transmission,a phase rotation of the transmitted symbols by a fixed angle is applied followed by a random component interleaver.Turbo codes with soft decision decoding and appropriate random channel interleavers are also considered.We present analytical expressions for the bit log-likelihood ratios(LLRs)that are needed for soft decision decoding at the MT turbo decoder,while the code combining technique is adapted to improve the end-to-end(E2E) performance.Then,we obtain through extensive computer simulations the average bit error probability(ABEP) of quadrature phase-shift keying(QPSK) signals received over pure land-mobile satellite(LMS)and pure CGS links for coding rates 1/3 and6/7.Moreover,the optimal rotation angles are obtained for both links.E2 E ABEP results are then presented assuming cooperation between GEO and CGS,while the power allocation issue is investigated under fixed total transmission power.Our performance evaluation results show that by using the constellation rotation technique,a performance gain can be achieved for high coding rates.

QTL Analysis of Chalkiness in Rice

A population of 150 recombination inbred lines （RILs） derived from the cross between rice varieties V20B and CPSLO17, was applied to locate the QTLs related to chalkiness traits and evaluate their genetic effects. A genetic linkage map was constructed based on 8 602 SLAF （specific-locus amplified fragment） markers, combine with the chatkiness traits of the tested lines. Four QTLs that related to chalkiness were detected using MapQTL 5 software, named qC-5a, qC-5b, qC-5c and qC-5d. The LOD threshold values of qC-5a, qC-5b, qC-5c and qC-5d were 4.02, 4.09, 3.94 and 4.1, respectively, explaining 11.6%, 11.8%, 11.2% and 11.8% of the observed phenotypic variance. All the four detected QTL alleles came from Iow-chalkiness parent V20B.

用竹根雕作的盆景艺术

盆景艺术历来受到人们的喜爱,而郑宝根创作的＂竹根雕盆景＂却把我们带向另一个艺术世界。简而言之竹根雕是以竹根为材料雕刻成的艺术品,竹根雕常用的是毛竹根,毛竹又名楠竹、孟宗竹,是我国竹类植物中分布最广、材质极好的竹种。毛竹的根部又长又大,周围丛生着密密的须根,以前是农家的燃料,然而,在独具慧眼的竹雕艺人手中,却能化为一件件精美的艺术品。