网络——人类相互沟通的桥梁

无限风光在网络 微电子技术的迅猛发展及其在人类社会生活各个领域中的广泛应用,正在改变着人类的社会生活方式,推动着社会的变革。将军不必亲临沙场,即可运筹帷幄、决胜千里;商人不必走遍世界,即可纵横商海、财源广进;文人不必上图书馆、阅览室查阅资料,即可著书立说;足不出户,即可看书读报、办公学习、购物诊病、休闲娱乐……天涯近在咫尺,世界就在眼前。

Prediction of the Helix/Sheet Content of Proteins from Their Primary Sequences by Neural Network Method

The amino acid composition and the biased auto-correlation function are considered as features, BP neural network algorithm is used to synthesize these features. The prediction accuracy of this method is verified by using the independent non-homologous protein database. It is shown that the average absolute errors for resubstitution test are 0.070 and 0.068 with the standard deviations 0.049 and 0.047 for the prediction of the content of α-helix and β-sheet respectively. For cross-validation test, the average absolute errors are 0.075 and 0.070 with the standard deviations 0.050 and 0.049 for the prediction of the content of α-helix and β-sheet respectively. Compared with the other methods currently available, the BP neural network method combined with the amino acid composition and the biased auto-correlation function features can effectively improve the prediction accuracy.

Exact Solutions of VNE: A Survey

Network virtualization is an enabling technology of running multiple virtual networks on a shared substrate network. It aims to deal with the ossification of current network architecture. As a crucial component of network virtualization, virtual network embedding(VNE) can efficiently and effectively allocates the substrate resource to proposed virtual network requests. According to the optimization strategy, VNE approaches can be classified into three categories: exact, heuristic and meta-heuristic solution. The VNE exact solution is the foundation of its corresponding heuristic and meta-heuristic solutions. This paper presents a survey of existing typical VNE exact solutions, and open problems for the future research of VNE exact solutions are proposed.

SPEECH EMOTION RECOGNITION USING MODIFIED QUADRATIC DISCRIMINATION FUNCTION

Quadratic Discrimination Function （QDF） is commonly used in speech emotion recognition, which proceeds on the premise that the input data is normal distribution. In this paper, we propose a transformation to normalize the emotional features, emotion recognition. Features based on prosody then derivate a Modified QDF （MQDF） to speech and voice quality are extracted and Principal Component Analysis Neural Network （PCANN） is used to reduce dimension of the feature vectors. The results show that voice quality features are effective supplement for recognition, and the method in this paper could improve the recognition ratio effectively.

微波传输与抗衰落措施

主要叙述微波传输特点、传输过程中所受影响 ,介绍了几种常见的抗衰落措施。

CDP1, a novel component of chloroplast division site positioning system in Arabidopsis

Chloroplasts are plant-specific organelles that evolved from endosymbiotic cyanobacteria. They divide through binary fission. Selection of the chloroplast division site is pivotal for the symmetric chloroplast division. In E. coli, positioning of the division site at the midpoint of the cell is regulated by dynamic oscillation of the Min system, which includes MinC, MinD and MinE. Homologs of MinD and MinE in plants are involved in chloroplast division. The homolog of MinC still has not been identified in higher plants. However, an FtsZ-like protein, ARC3, was found to be involved in chloroplast division site positioning. Here, we report that chloroplast division site positioning 1 （AtCDP1） is a novel chloroplast division protein involved in chloroplast division site placement in Arabidopsis. AtCDP1 was discovered by screening an Arabidopsis cDNA expression library in bacteria for colonies with a cell division phenotype. AtCDP1 is exclusively expressed in young green tissues in Arabidopsis. Elongated chloroplasts with multiple division sites were observed in the loss-of-function cdpl mutant. Overexpression of AtCDP1 caused a chloroplast division phenotype too. Protein interaction assays suggested that AtCDP1 may mediate the chloroplast division site positioning through the interaction with ARC3. Overall, our results indicate that AtCDP1 is a novel component of the chloroplast division site positioning system, and the working mechanism of this system is different from that of the traditional MinCDE system in prokaryotic cells.

Simulation of Morphologies and Mechanical Properties of A/B Polymer Blend Film

The effects of blend composition and micro-phase structure on the mechanical behavior of A/B polymer blend film are studied by coupling the Monte Carlo(MC) simulation of morphology with the lattice spring model(LSM) of micro mechanics of materials.The MC method with bond length fluctuation and cavity diffusion algorithm on cubic lattice is adopted to simulate the micro-phase structure of A/B polymer blend.The information of morphology and structure is then inputted to the LSM composed of a three-dimensional network of springs to obtain the mechanical properties of polymer blend film.Simulated results show that the mechanical response is mainly affected by the density and the composition of polymer blend film through the morphology transition.When a force is applied on the outer boundary of polymer blend film,the vicinity of the inner cavities experiences higher stresses and strains responsible for the onset of crack propagation and the premature failure of the entire system.

The retromer component SNX6 interacts with dynactin p150Glued and mediates endosome-to-TGN transport

The retromer is a protein complex that mediates retrograde transport of transmembrane cargoes from endosomes to the trans-Golgi network （TGN）. It is comprised of a cargo-selection subcomplex of Vps26, Vps29 and Vps35 and a membrane-binding coat subcomplex of sorting nexins （SNXs）. Previous studies identified SNX1/2 as one of the components of the SNX subcomplex, and SNX5/6 as candidates for the second SNX. How the retromer-associated cargoes are recognized and transported by molecular motors are largely unknown. In this study, we found that one of SNX1/2＇s dimerization partners, SNX6, interacts with the p150Gued subunit of the dynein/dynactin motor complex. We present evidence that SNX6 is a component of the retromer, and that recruitment of the motor complex to the membrane-associated retromer requires the SNX6-pl50Gued interaction. Disruption of the SNX6-pl50Glued interaction causes failure in formation and detachment of the tubulovesicular sorting structures from endosomes and results in block of CI-MPR retrieval from endosomes to the TGN. These observations indicate that in addition to SNX1/2, SNX6 in association with the dynein/dynactin complex drives the formation and movement of tubular retrograde intermediates.

Chronological Restoration of Fort Frontenac in 3D for Heritage Visualization

This paper is composed of three elements： 3D modeling, web design and heritage visualization on the basis of the chronological restoration of Fort Frontenac in 1673, 1675, 1680, 1685 and 1688, changing from narrow and plain to broad, grand features. The aim is to use computer graphic design to inform and create an interest in historical visualization by rebuilding Fort Frontenac using 3D modeling and interactive design. The final model can be integrated into an interactive website to learn more about the fort＇s historic importance. It is apparent that using computer graphics can save time and money when it comes to historical visualization. Visitors do not have to travel to the actual archaeological buildings and can simply use the web in their own homes to learn about this information virtually. In order to create a sophisticated restoration of archaeological buildings, meticulously assessing historical records will draw viewers into the visualizations, such as the historical world of Fort Frontenac. As a result, the completed restoration allows the viewers to effectively understand the fort＇s social system, habits and historical events.

Self-similar traffic analysis in optical burst assembly

This paper investigates the traffic properties before and after assembly at edge node of Ethernet over optical burst switching （OBS） network for the first time. Burst and inter-arrival time distributions are simulated under time-based and length-based assembly schemes. Self-similar traffic Hurst parameter is compared through R/S and V/T plot. Finally three self-similar traffic generating methods are given. Simulation resuhs demonstrate that, muhi-source traffic increases self-similar degree, however after assembly, time-based scheme can decrease self similar degree, and aggregated burst size is close to Gaussian distribution. Length-based method has no effects on the self-similarity of input traffic. RMD is fit for study of burst network with large self-similarity.

Site-Floristic Variability of Foxteil Meadows in Poland

On the basis of multifaceted investigations of approximately 600 phytosociological surveys of foxtail meadows taken in years 2002-2012 in river valleys with the assistance of the Braun-Blanquet method, the authors carried out evaluation of the floristic composition with respect to phytosociological structure, floristic variability, degree of synanthropisation and life form structures. In addition, they ascertained the dependence of floristic variability of Alopecuretum pratensis phytocenoses on site conditions determined using： the phytoindication method and the laboratory analyses assessed the soil content of available forms of P and K and of Mg. The greatest areas among the recognised syntaxons are taken up by patches of a typical sub-association developed in fresh sites on soils of lightly acid reaction and moderate nitrogen availability. Floristic variability of Alopecuretum pratensis is characterised by： presence in the phytosociological structure of species characteristic for other syntaxons, floristic abundance and botanical structure, domination of species of the 1 st and 2nd degree of stability, high proportion of synanthropic species, values of the floristic diversity index （H＇）, natural and fodder score values. Geobotanical variability of foxtail meadows confirms difficulties with unequivocal determination of the systematic position of the Alopecuretum pratensis association.

Study on the network delay of periodic information in the NCS based on EPA

The network delay of the periodic messages transmission in the network control system （NCS） based on Ethemet for plant automation （EPA） is analyzed from the theoretical and experimental perspective in this paper. The composition and the characteristics of the network delay of EPA periodic messages transmission in a subnet is studied through analyzing the information transmission regularity and EPA deterministic scheduling mechanism. On this basis, the queuing delay at communication schedule management entity （EPA _ CSME） that is the most important component of network delay is analyzed, during which the formulas for the queuing delay of periodic messages and other real time parameters are proposed. Furthermore, an experiment is developed to test each component of network delay of periodic messages transmission in a EPA subnet. According to the experimental and the theoretical analysis, the conclusion is drawn that the delay during which the periodic messages wait for the periodic messages transmission time slice is the main factor that causes considerable network delay, and improvement method is presented.

Forecasting available parking space with largest Lyapunov exponents method

The techniques to forecast available parking space(APS) are indispensable components for parking guidance systems(PGS). According to the data collected in Newcastle upon Tyne, England, the changing characteristics of APS were studied. Thereafter, aiming to build up a multi-step APS forecasting model that provides richer information than a conventional one-step model, the largest Lyapunov exponents(largest LEs) method was introduced into PGS. By experimental tests conducted using the same dataset, its prediction performance was compared with traditional wavelet neural network(WNN) method in both one-step and multi-step processes. Based on the results, a new multi-step forecasting model called WNN-LE method was proposed, where WNN, which enjoys a more accurate performance along with a better learning ability in short-term forecasting, was applied in the early forecast steps while the Lyapunov exponent prediction method in the latter steps precisely reflect the chaotic feature in latter forecast period. The MSE of APS forecasting for one hour time period can be reduced from 83.1 to 27.1(in a parking building with 492 berths) by using largest LEs method instead of WNN and further reduced to 19.0 by conducted the new method.

Combination of Ecoprofile and Least-cost Model for Eco-network Planning

The protecting requirements and functional connectivity of species in isolated habitat patches are crucial factors of eco-network planning.This study aimed to improve the method of eco-network planning for species conservation.Ecoprofiling was used to group the species by similar behavior types,namely,choice of ecosystem,area requirement,and short distance dispersal abilities.A least-cost model was used to simulate the optimal corridor location to maintain functional connectivity.A combination of ecoprofile and least-cost model was hired to develop an eco-network that promoted species conservation.A case study was also conducted in Beijing,China.In addition to the required ecosystem,habitat area is an important parameter for habitat extraction.Habitat area can remove noise habitat patches because of lacking area.Short-distance dispersal can be used to identify corridor requirements and avoid unnecessary building requirements.Species with various dispersal abilities exhibit significant differences in terms of corridor length and location requirement.Habitat isolation is the main threat for weakly mobile species,and habitat loss is the major risk of mobile species protection.Different species groups also exhibit distinct landscape pattern demands for an eco-network,and the eco-network planning based on specific species can not protect other species.We proposed that a combination of ecoprofile and least-cost model improved the efficiency of species conservation by eco-network planning.

Online Edutainment Videos Recontextualizing and Reconceptualizing Expert Discourse in a Participatory Web-culture

The online world is becoming more and more edutainment, where learning, getting informed and entertained seem to be part of one and the same activity. As a result of this current fascination, people are drawn increasingly towards a new genre, i.e. free online 20-minute long lectures that borrow from film and storytelling techniques, that are offering an engaging series of speeches and even courses in many different scientific subjects. Though English as a lingua franca is still the dominant language of the internet, as a result of a growing new trend, namely crowdsourcing translation, knowledge dissemination is further enhanced and is now reaching further into many different cultures, allowing even the so-called minor languages to regain dignity and circulate, by engaging native speakers from different cultural backgrounds. This paper offers an overview on the phenomenon of online edutainment considering the role played by collaborative users who not only enjoy but also create and translate content. In addition, a case study focused on TED Talks allows a more in depth analysis of the new genre and the increasing need for subtitling scripts.

灵活高效的无线接入解决方案——朗讯CDMA450介绍

介绍了CDMA450的由来、当前的市场情况、技术特点、支持的业务、网络发展以及朗讯CDMA450的网络解决方案等。

Research on Incentive Mechanism of Virtual Community Knowledge Sharing

With the continuous development of Internet technology, the network has become an important part of people＇s lives, the emergence of virtual communities is promoting the deep interaction oflntemet users, but it is found that the virtual community ＂diving party＂ is more and more through investigation and literature research, The quantity and quality of knowledge sharing are declining. Therefore, this paper summarizes the behavior and influencing factors of knowledge sharing in virtual community through literature research and investigation and research. At the same time, through the research of incentive theory, the author has obtained the incentive method and content of knowledge sharing, and established the incentive mechanism. The bright spot is to perfect the theory of knowledge sharing while transforming theory into practice, and to provide suggestions for the development of incentive mechanism of virtual community.

Research on the oral teaching of university network English in promoting students＇ creative thinking abilities

Many authors probe into the models of promoting college students＇ creative thinking abilities from their own perspectives, among which there are innovative works. However, whether we can improve the above abilities of college students in the oral teaching of university network English still remains blank in the study. Based on the deconstruction of the creative thinking abilities of the students, we should build the components of this capacity from four aspects.

IMMUNOHISTOCHEMICAL DISTRIBUTION OF ERYTHROPOIETIN AND ITS RECEPTOR EXPRESSION IN POSTNATAL RAT RETINA DEVELOPMENT

Objective To investigate the distribution of erythropoietin （EPO） and erythropoietin receptor （ EPOR ） expression in the postnatal rat retina development. Methods Forty-two male Sprague-Dawley rats were divided into 7 groups according to their various postnatal days： postnatal 1 d （D1 group）, 3 d （D3 group）, I week （W1 group）, 2 weeks （W2 group）, 3 weeks （W3 group）, 4 weeks （W4 group） and8 weeks （W8 group） （ n = 6 ）. Single eye was randomly chosen from each rat for the study. The retinal sections were stained with hematoxylin and eosin （HE） and used for the retina development observation. Immunohistochemical staining was used to localize EPO and EPOR expressions in retinas.of differentstages of development, and the expression intensities were determined by an image plus 4 program~~ Results The retinal inner nuclear layer （INL） and outer nuclear layer （ONL） were mixed together and had not yet fully differentiated in D1 and D3 groups. The INL and ONL formed their own independent regions and the outer plexiform layer （OPL） appeared between two layers in W1 group. With the postnatal retinal development, the inner plexiform layer （ IPL ） , rods and cones layer （ RCL ）, and OPL were gradually widened and stabilized in W2 to W3 groups. EPO/EPOR expressions located prominently in the inner part of the postnatal rat developing retinas. The expression of EPO in GCL and INL gradually increased from DI to W4, then the expression decreased in W8. Expression of EPOR in GCL gradually increased from DI to WI , then decreased in W2 ; and it gradually increased again from W3 to W8. Expression of EPOR in INL gradually increased from D1 to W1, then decreased in W2 ; and it continued to decrease from W3 to W8. Expression of EPOR in the external segment of RCL gradually increased from D1 to W8. However, expression in the internal segment of RCL gradually decreased from D1 to W3 , then no obvious expression was seen in the internal segment of RCL in W4 and W8. Conclusion EPO/EPOR expressions locate prominently in the inner part of the postnatal rat developing retina. And EPO/EPOR expressions in the rat retinas exist the dynamic changes during the postnatal retina development period.

An Improved Method for Modeling Spatial Distribution of δD in Surface Snow over Antarctic Ice Sheet

Using the recent compilation of the isotopic composition data of surface snow of Antarctic ice sheet, we proposed an improved interpolation method of δD, which utilizes geographical factors （i.e., latitude and altitude） as the primary predictors and incorporates inverse distance weighting （IDW） technique. The method was applied to a high-resolution digital elevation model （DEM） to produce a grid map of multi-year mean δD values with lkm spatial resolution for Antarctica. The mean absolute deviation between observed and estimated data in the map is about 5.4‰, and the standard deviation is 9‰. The resulting δD pattern resembles well known characteristics such as the depletion of the heavy isotopes with increasing latitude and distance from coast line, but also reveals the complex topographic effects.