基于ARM9的SMS服务平台

介绍了一种将嵌入式平台与GPRS短消息数据传输模式相结合构建的无线数据传输系统,系统以三星公司的ARM9系列产品S3C2440为核心,配合GPRS模块实现了一个中文短消息的服务平台。文章简要介绍了系统硬件平台的搭建,重点介绍了系统软件架构及开发环境,特别详述了一种将纯ASCII字符信息与其他信息采用不同编码模式分别处理的方法。实际的测试表明该系统很好地满足了设计要求,并且具有结构简单、功耗低、可扩展性强等特点。     

一种核属性快速求解算法

针对求核算法存在所求得的核与基于正区域的核不一致以及算法的时间和空间复杂度不理想的问题,提出一种新的求核方法,并证明了由该方法所获得的核与基于正区域的核是一致的.利用分布计数基数排序方法设计了一种高效的等价类求解算法,在此基础上给出了快速求核算法.实验表明,所提出的算法是正确而高效的.     

Analysis of E-learning innovation and core capability using a hypercube model

New information and communication technologies and emerging learning models have triggered a new wave of educational innovation-electronic learning (E-learning). This study utilizes a hypercube innovation model to analyze the differences in technology and learning models (instruction model/environment) used in traditional classroom learning versus E-learning environments. The results show that the innovation from traditional classroom learning to E-learning is radical for both the learner and instructor, leading to drastic changes in the technology and learning model. For educational institutions, the technology is a fundamental change, while the learning model is reinforced. From the dynamic capability perspectives, a set of core capabilities needed for successfully exploiting E-learning is identified. These results provide insight for learners, instructors and educational institutions for enhancing their understanding of E-learning innovation, and provide guidelines to help E-learning stakeholders adapt from the traditional classroom to E-learning environments.     

Rational Design of Colloidal Core/Shell Quantum Dots for Optoelectronic Applications

Colloidal core/shell quantum dots (QDs) are promising for solar technologies because of their excellent optoelectronic properties including tunable light absorption/emission spectra, high photoluminescence quantum yield (PLQY), suppressed Auger recombination, efficient charge separation/transfer, and outstanding photo-/thermal-/chemical stability. In this review, engineered core/shell QDs with various types of band structures and corresponding device performance in luminescent solar concentrators (LSCs), light-emitting diodes (LEDs), solar-driven photoelectrochemical (PEC) devices, and QDs-sensitized solar cells (QDSCs) are summarized. In particular, the applications of interfacial layer engineering and eco-friendly, heavy metal-free core/shell QDs in optoelectronic devices are highlighted. Finally, strategies towards the developments and practical perspectives of core/shell QDs are briefly mentioned to offer guidelines for achieving prospective high-efficiency and long-term stable QD devices.     

5G SA终端发现方案

本文以用户“不登记”使用5G SA网络为目标,采用PCRF/PCF/OCS联合发现机制,从附着、注册信令和在线计费请求消息中分析识别用户的IMEI信息,与5G SA 终端IMEI库做比对,判断用户是否采用5G SA终端,实时捕捉用户换机行为,找到了5G业务开通的触发点,实现了5G SA终端在不同网络场景下被发现的方案,实时、准确、无遗漏地锁定5G目标用户。     

Formation mechanism and magnetic performance of Fe-Si soft magnetic composites coated with MnO-SiO2 composite coatings

Fe-Si soft magnetic composites (SMCs) coated with MnO-SiO₂ composite coatings were fabricated via sintering the ball milled Fe-Si/MnO₂ composite powders. The transformation mechanism from MnO₂ coating to MnO-SiO₂ composite coatings was studied. The effect of MnO₂ content on the microstructure and magnetic properties of Fe-Si soft magnetic composites has also been investigated systematically. The analysis results indicated that MnO₂ would be reduced to MnO by Si in the Fe-Si particles at 780.1 ℃. When the temperature reached 985.8 ℃, the generated MnO and SiO₂ would further combine to form 2MnO·SiO₂, finally forming the MnO-SiO₂ composite coatings. With the increase of the MnO₂ content from 0.0 wt% to 10.0 wt%, the MnO-SiO₂ composite coatings became thicker, thus the saturation magnetization and permeability decreased gradually. However, exorbitant MnO₂ content above 5.0 wt% would result in excessive in-situ Fe existed in the composite coatings and obvious reduction of Si content in the Fe-Si particles due to the above solid-state reactions. Therefore, the increasing trend of the resistivity was weakened. And the 5.0 wt% MnO₂ coated Fe-Si SMCs exhibited superior comprehensive performance such as high saturation magnetization (186.5 A·m²/kg), good permeability (71), low total core loss (362.6 mW/cm³ at 50 kHz).     

The core-shell structured Fe-based amorphous magnetic powder cores with excellent magnetic properties

The Fe-based soft magnetic amorphous powder cores (AMPCs) with excellent comprehensive magnetic properties were successfully designed and fabricated using the core-shell structured FeSiBCCr/TiO₂ composite powders. The influence of the concentration of water (H₂O) for the magnetic performance of the AMPCs has been systematically studied based on careful analysis of the process of nucleation and growth of TiO₂ under different H₂O concentration in the reaction system. The growth process for the TiO₂ coating layer with the H₂O concentration in the range of 0.01–0.02 ml/g corresponds to the heterogeneous nucleation phase, while the mixing phase of heterogeneous and homogeneous nucleation occurs when the concentration of H₂O increases to 0.03 ml/g. Optimized soft magnetic properties have been achieved for the AMPCs with H₂O concentration of 0.02 ml/g, including high permeability of 81.5 with a high frequency stability up to 10 MHz, high quality factor of 102 at 530 kHz, low core loss of 42 mW/cm³ at 500 kHz for B_m = 0.01 T, and better DC-bias property of 52% at a bias field of 100 Oe due to the uniform and proper thickness insulation coating layer, which can be used to produce miniature magnetic components for applications in medium and high-frequency fields.     

Controllable SiO2 insulating layer and magnetic properties for intergranular insulating Fe-6.5wt.%Si/SiO2 composites

In this study, the intergranular insulating Fe-6.5wt.%Si/SiO₂ soft magnetic composites (SMCs) were prepared successfully using in-situ chemical deposition followed by the spark plasma sintering (SPS) process. The effects of ammonia concentration on the microstructure and magnetic properties of the composites have been studied systematically. The Fe-6.5wt.%Si alloy particles could be well insulated by the uniform SiO₂ insulating layer, and its thickness increases with increasing the ammonia concentration from 0 to 0.02?ml/g. However, further increasing the ammonia concentration to 0.03 and 0.04?ml/g would result in the discontinuous and uneven SiO₂ insulating layer. Correspondingly, the saturation magnetization and effective permeability of the composite compacts first decrease and then increase with increasing the ammonia concentration from 0.00 to 0.04?ml/g, whereas the coercivity and resistivity vary in the opposite tendency. Note that the overall performances such as the frequency stability of effective permeability, higher resistivity and lower total core loss, reach the optimal value for the sample with the ammonia concentration of 0.02?ml/g.     

浅谈计算机网络专业模拟公司制教学

计算机网络专业的相关专业核心课程多为知识综合度高、实践性较强的课程,传统的教学模式已经不能完全适应现代社会的发展,需采用新的教学模式来提高学生的学习主动性,提高学习效率,同时提高学生的企业适应能力.     

高校云计算中心网络架构设计与实现

使用成熟的、商用化的云计算技术改造现有数据中心,建立一套稳定和可持续发展的云计算数据中心架构,以满足业务长期持续的扩展能力,云数据中心网络的逻辑架构是建立在融合的虚拟化架构基础上的.而传统的逻辑设计,包括VLAN规划、路由和地址结构等,都应服务于新的融合的虚拟化架构.