多粒子纠缠态QTDM通信方案及QMU协议

分析了未知的三个三态粒子纠缠态的隐形传送过程,结合纠缠源的特性,提出了量子信道时分复用方案.同时还提出了一种可传送多粒子纠缠态的量子时分多路通信方案和量子多用户协议.研究结果表明,该方案与采用BB84协议的量子通信系统相比,不仅能够实现量子多用户安全保密通信,而且误码率低.     

Optimizing the imaging of the monkey auditory cortex: sparse vs. continuous fMRI

The noninvasive imaging of the monkey auditory system with functional magnetic resonance imaging (fMRI) can bridge the gap between electrophysiological studies in monkeys and imaging studies in humans. Some of the recent imaging of monkey auditory cortical and subcortical structures relies on a technique of “sparse imaging,” which was developed in human studies to sidestep the negative influence of scanner noise by adding periods of silence in between volume acquisition. Among the various aspects that have gone into the ongoing optimization of fMRI of the monkey auditory cortex, replacing the more common continuous-imaging paradigm with sparse imaging seemed to us to make the most obvious difference in the amount of activity that we could reliably obtain from awake or anesthetized animals. Here, we directly compare the sparse- and continuous-imaging paradigms in anesthetized animals. We document a strikingly greater auditory response with sparse imaging, both quantitatively and qualitatively, which includes a more expansive and robust tonotopic organization. There were instances where continuous imaging could better reveal organizational properties that sparse imaging missed, such as aspects of the hierarchical organization of auditory cortex. We consider the choice of imaging paradigm as a key component in optimizing the fMRI of the monkey auditory cortex.     

The position value in communication structures

We study cooperation structures with the following property: given any two feasible coalitions with non-empty intersection, its union is a feasible coalition again. TU-games restricted by union stable systems generalize graph-restricted games and games with permission structures. A study about the differences between the position value in union stable systems and hypergraph communication situations is given. Moreover, some computational aspects related to position value in union stable systems are discussed.This research has been partially supported by the Spanish Ministery of Science and Technology, under grant SEC2003-00573.     

Applications of the Internet to PT

The Internet provides laboratory professionals with a unique opportunity to come together as a network and to develop an integrated system for monitoring the quality of testing in their laboratories on a real-time basis. Once established this network could provide a quality and standards promoting infrastructure for catalyzing the standardization process. Through a collaborative sharing of information on performance and through the use of a common database with harmonized test materials, proficiency testing providers can play a pivotal role in developing such a system. The challenge is now up to us.     

基于物联网的小区智能照明管理系统设计与实现

针对国内中小型LED照明企业的艰难处境和政府倡导低碳,绿色环保照明政策现状,提出了一种基于电力载波通信技术的小区智能照明管理系统的设计方案。采用微控制器、PLC芯片和传感器构建智能控制终端,实现对单灯电能、光强度等数据采集。集中器集成GPRS通信模块负责与远程控制中心建立连接,控制终端与集中器通过电力线相连,实现PC端和移动端对LED照明设备的多平台控制。重点阐述了智能控制终端的软硬件设计、系统的自定义通信协议和远程控制方法。系统实测结果表明,该系统数据传输可靠、响应时间短、成本低,易于进行远程管理和控制。     

Present-day communication in chemistry--problems and possibilities

This article deals with the problems and possibilities in the present-day communication of chemical results and opinions. Personal communications as well as primary and secondary literature have to be supplemented in the future by documentation and information services which use modern electronic data processing equipment.     

Chemically Fueled Communication Along a Scaffolded Nanoscale Array of Squaramides

Relaying conformational change over several nanometers is central to the function of allosterically regulated proteins. Replicating this mechanism artificially would provide important communication tools, but requires nanometer-sized molecules that reversibly switch between defined shapes in response to signaling molecules. In this work, 1.8 nm long rigid rod oligo(phenylene-ethynylene)s are scaffolds for switchable multi-squaramide hydrogen-bond relays. Each relay can adopt either a parallel or an antiparallel orientation relative to the scaffold; the preferred orientation is dictated by a director group at one end. An amine director responded to proton signals, with acid-base cycles producing multiple reversible changes in relay orientation that were reported by a terminal NH, which is 1.8 nm distant. Moreover, a chemical fuel acted as a dissipative signal. As the fuel was consumed, the relay reverted to its original orientation, illustrating how information from out-of-equilibrium molecular signals can be communicated to a distant site.     

Students’ and Teachers’ Conceptual Metaphors for Mathematical Problem Solving

Metaphors are regularly used by mathematics teachers to relate difficult or complex concepts in classrooms. A complex topic of concern in mathematics education, and most STEM‐based education classes, is problem solving. This study identified how students and teachers contextualize mathematical problem solving through their choice of metaphors. Twenty‐two high‐school student and six teacher interviews demonstrated a rich foundation for these shared experiences by identifying the conceptual metaphors. This mixed‐methods approach qualitatively identified conceptual metaphors via interpretive phenomenology and then quantitatively analyzed the frequency and popularity of the metaphors to explore whether a coherent metaphorical system exists with teachers and students. This study identified the existence of a set of metaphors that describe how multiple classrooms of geometry students and teachers make sense of mathematical problem solving. Moreover, this study determined that the most popular metaphors for problem solving were shared by both students and teachers. The existence of a coherent set of metaphors for problem solving creates a discursive space for teachers to converse with students about problem solving concretely. Moreover, the methodology provides a means to address other complex concepts in STEM education fields that revolve around experiential understanding.     

一种800MHz无线通信用高温超导滤波器的研究

本文设计了应用于800MHz无线通信系统基站的8节和14节高温超导滤波器,中心频率在800MHz附近,相对带宽为2.1%,并在以0.51mm厚度的MgO为衬底的双面YBCO薄膜上制作了14节滤波器.测试结果表明,该滤波器具有较好的性能,在60K温度下,其带内插损小于0.3dB,带边陡峭度大于25dB/MHz,带外抑制优于70dB.     

具有旋转连接功能的双层光互连网络设计

在设计的双层光互连网络中,上层网络是星型连接,依靠数字路由结点进行通信.单通道最大传输速率为1.4 Gbps,数字路由结点吞吐率大于10 Gbps,底层为网络接口卡和结点机连成的环形网,峰值传输速率为1.056 Gbps.在底层网络中个别结点机与传感器之间配置有光纤旋转连接器,可传输动态数据.经计算,环网内最大通信延迟时间小于5.292 μs,互连网络的平均通信延迟时间为11.03 μs,环形网络的最大数据传输带宽为50 Mbit/s.