基于LM3S316的微控制器仿真USB设备

提出了基于LM3S316实现与PC机通讯的方法.给出了硬件实现及软件设计思想.该方法使用微控制器仿真USB设备,降低了功耗、成本.     

A novel fault-tolerant execution model by using of mobile agents

The exponential expansion of the Internet and the widespread popularity of the World Wide Web give a challenge to experts on reliable and secure system design, e.g., e-economy applications. New paradigms are on demand and mobile agent technology is one of the features. In this paper, we propose a fault-tolerance execution model by using of mobile agents, for the purpose of consistent and correct performance with a required function under stated conditions for a specified period of time. Failures are classified into two classes based on their intrinsic different effects on mobile agents. For each kind of failure, a specified handling method is adopted. The introduction of exceptional handling method allows performance improvements during mobile agents’ execution. The behaviors of mobile agents are statistically analyzed through several key parameters, including the migration time from node to node, the life expectancy of mobile agents, and the population distribution of mobile agents, to evaluate the performance of our model. The analytical results give new theoretical insights to the fault-tolerant execution of mobile agents and show that our model outperforms the existing fault-tolerant models. Our model provides an effective way to improve the reliability of computer systems.     

Ubiquitous Personal Study: a framework for supporting information access and sharing

The information resources on the Web are diversified, the amount of which is increasing rapidly. Demands for selecting useful information from the Internet, managing personal contents, and sharing contents under control have risen. In this study, we propose the Ubiquitous Personal Study, a framework of personalized virtual study to support accessing, managing, organizing, sharing and recommending information. In this paper, we focus on discussing the framework, and design and implementation issues on how to implement it with Web 2.0 mash-up technology and Open Source Software.     

压缩应力下（Tb,Dy）Fe2磁致伸缩的研究

本文利用自制的磁致伸缩测量仪和“ｊｕｍｐ”效应测量仪研究了在一定压强了多晶（Ｔｂ、Ｄｙ）Ｆｅ２棒的磁致伸缩,发现加压时,在一定工艺条件下制作的（Ｔｂ、Ｄｙ）Ｆｅ２棒会有磁致伸缩的变化。卸载后经过热处理,磁致伸缩值在不加压时也会维持一个高值。     

过敏原肌质钙结合蛋白在毕赤酵母中的表达、优化及免疫反应性研究

目的 探究天然肌质钙结合蛋白(sarcoplasmic calcium binding protein, SCP)的可替代物,为蟹类过敏原的检测提供基础材料,本研究首次利用毕赤酵母(Pichia pastoris, P. pastoris)高效表达表达三疣梭子蟹(Portunus trituberculatus)重要过敏原SCP,并检验其免疫反应性。方法 根据毕赤酵母的密码子偏好性优化SCP基因并构建重组质粒。将其热激转化至P. pastoris GS115菌株后经遗传霉素(Geneticin, G418)筛选获得阳性高拷贝子。最后通过甲醇诱导表达重组SCP并结合免疫印记(Western blotting, WB)和间接酶联免疫吸附实验(enzyme-linked immunosorbent assay, ELISA)验证其免疫反应性。结果 SCP在P. pastoris GS115中实现了可溶性高效表达,其表观分子量约为28 kDa。在摇瓶水平下,最佳诱导条件为pH为6.0、每24 h添加1.0%(v/v)甲醇,于28℃发酵144 h,在此条件下,纯度为91.6%的SCP产量可达15 mg/L。WB和间接ELISA结果表明,重组SCP具有IgG结合能力。结论 毕赤酵母表达系统可以得到纯度较高且免疫反应性良好的重组SCP。本研究为SCP的理化研究及产业化应用奠定了基础,并有望促进特异性甲壳类过敏原检测的发展。     

佛手凉果加工过程中功能性成分与抗氧化性分析

佛手凉果是具有功能特性的岭南特色凉果品种,探究佛手凉果制作过程中功能性成分及其体外抗氧化活性变化规律,可为佛手凉果产业工艺优化与改良提供依据。结果表明,加工提高了佛手中总酸、多糖、黄酮和膳食纤维含量,导致多酚含量下降。制作过程中,1,1－二苯基－2－三硝基苯(DPPH)自由基、2,20 -联氮- 2 -三硝基苯肼(ABTS)自由基清除能力和铁离子还原抗氧化能力(Ferric Reducing Antioxidant Power, FRAP)呈现先下降后上升的趋势,效果分别是新鲜佛手的1.35倍、1.57倍和2.16倍。总黄酮与FRAP之间呈现极显著相关性(P＜0.01);与DPPH、ABTS呈显著相关性(P＜0.05);有机酸、总多糖分别与ABTS和FRAP之间相关性(P＜0.05)。为此,在佛手凉果的制作过程中,糖制和干燥工艺对功能性成分的转化与浓缩起关键作用,可作为工艺优化的重点。     

Metal Ions versus Protons: Tracking of Charge-Carrier Insertion into a Cathode Oxide in Aqueous Rechargeable Batteries

Protons in aqueous electrolytes can perform as an additional type of charge carrier for insertion/extraction in addition to the primary carrier cations in aqueous rechargeable batteries. Despite many diverse claims regarding the effect of protons, mutually conflicting experimental results and their interpretations without direct evidence have been reported over the last decade. Systematic examinations and analyses are thus imperative to clarify the conditions of proton insertion in aqueous rechargeable batteries. Utilizing V₂O₅ as a model cathode and beaker-type cells with a sufficient amount of ZnSO₄ aqueous electrolytes in this work, it is demonstrated that protons are inserted into the cathode prior to Zn-ions in low-pH conditions (pH ≤ 3.0). In stark contrast, the influence of protons on the discharge voltage and capacity is insignificant, when either the pH becomes higher (pH ≥ 4.0) or the electrolyte volume is considerably low in coin-type cells. Similar behavior of pH-dependent proton insertion is also verified in Na–, Mg–, and Al-ion electrolytes. Providing a resolution to the controversy regarding proton insertion, the present study emphasizes that the influence of protons substantially varies depending on the pH and relative volume of electrolytes in aqueous batteries.     

热处理非晶态Ni-P合金镀层的晶化过程

运用电沉积的方法在45钢基体上制备Ni-P合金镀层,使用差示扫描量热法(DSC)和热重法(TG)分析非晶态NiP合金镀层在20℃/min加热速率下的热效应和质量变化。在300℃和400℃分别对镀层进行0,15,30,45,60,75min的热处理,采用扫描电镜(SEM)、能谱仪(EDS)、X射线衍射仪(XRD)、显微硬度计对镀层进行表征。结果表明:Ni-P合金镀层在加热过程中的放热峰出现在284.8℃处,镀层的质量和元素组成稳定;晶化过程经历了非晶态、亚稳态NiP和Ni5P2、稳定态Ni3P的转变;经过热处理后,镀层的显微硬度显著提高,最大值达1036.56HV,约为镀态的2倍;热处理态镀层的耐NaCl溶液腐蚀性能比镀态有所下降,但两者都比45钢基体好。     

基于水印和密码的数字版权管理模型的研究

在分析了数字版权研究现状和功能框架的基础上,设计了基于多重数字水印和密码的版权管理模型;该模型采用数字内容和许可证各自单独封装、独立分发的方式,使得只有购买了许可证的特定用户才能使用数字内容,实现了水印作品的许可交易;另外,内容服务器采用的对数字作品加载两次水印,对数字内容部分签名加密,未加密部分签名的方案,在有效保证数字内容安全传输的基础上又减少了计算量和存储量;分析表明该模型有显著的优点和很好的安全性。     

现代空间环境中屏风设计理念的拓展和延伸

本文着重论述了在现代空间环境中如何拓展和延伸屏风的设计理念,使其在丰富多元的现代社会中具有更广阔的发展空间,并符合现代人的需求。