基于UPnP和UPnP AV的多媒体内容同步和回放

简要描述了基于UPnP技术架构和UPnP AV规范的家庭娱乐系统(HES)的实现方案,在HES中提出了设备选择算法、轻量级可切换播放服务和快速同步算法.设备选择算法实现了用户零干预条件下的自动切换,轻量级可切换播放服务提供了一个简单高效的服务实现,而快速同步算法将媒体播放切换动作前的同步时间降低到秒数量级,与传统内容同步方法分钟级的延时相比具有重要的使用价值.     

基于PT2258的AV5.1多声道音响控制系统

介绍基于PT2258的红外遥控AV5.1音响控制系统的软硬件设计。该设计以功能强大的六声道音量控制集成电路PT2258,辅以PIC16C56微控制器,对声道进行选择输入、集中控制,软硬件设计均采用模块化结构的设计思想,使得AV5.1音响控制系统具有使用方便、性价比高等特点。     

HomePlug AV系统及其数据传输机制

HomePlugAV是近年来兴起的一种电力线通信技术,文章通过分析电力线通信技术的应用优势,介绍了电力线通信技术标准的最新发展,阐述了HomePlugAV系统的体系结构、HomePlugAV的数据传输机制,并对基于HomePlugAV的电力线通信技术的应用前景进行了展望。     

Perturbation method analysis of AC-induced corrosion

A nonlinear model for corrosion of metals subjected to alternating voltage (AV) induced corrosion that includes the elements corresponding to the polarization resistance, the double layer capacitance and the solution resistance is developed. The results show that corrosion of materials under AC conditions is greatly enhanced by the peak potential and by an increase in the ratio of the anodic-to-cathodic Tafel slope. The AC-induced corrosion rate: (i) decreases with the frequency of the applied signal and with an increase in the DC corrosion potential, (ii) is independent of the DC corrosion rate, and (iii) increases with the peak potentials of the AV signal.     

拨号联网研究AV新技术指南

本文介绍了通过普通电话线如何把个人计算机连接到Ｉｎｔｅｒｎｅｔ网络，以有如何使用Ｗｅｂ浏览器来研究ＡＶ新技术，改变研究ＡＶ的传统方式。     

油炸辣椒品质影响因素的研究

过氧化值(peroxide value,POV)和酸价(acid value,AV)是衡量油脂及其油炸食品品质的两个重要因素,由于它们的变化受到油炸过程中各种参数的影响,探讨了在油炸过程中油炸原料、油炸时间、油炸温度、水分对产品质量变化情况的影响.     

Formation of the beef flavour precursors and their correlation with chemical parameters during the controlled thermal oxidation of tallow

Thermal oxidation of tallow was assayed by peroxide value (PV), p-anisidine value (p-AV), and acid value (AV), and the volatile compounds produced at different oxidation conditions were analysed by SPME-GC/MS. The accumulation of characteristic beef flavour precursors, such as hexanal, 1-octen-3-ol, (E,E)-2,4-decadienal and (E,E)-2,4-heptadienal, reached a maximum value when heated at 140 °C for 2 h with an air flow of 75 l/h per 100 g tallow, whereas at the same temperature PV and p-AV were both at high levels, and AV was relatively low. A correlation analysis of chemical parameters and volatile compounds showed that the beef flavour precursors were positively related to PV, and the off-flavour compounds were highly correlated to AV. Therefore, a moderate oxidation of tallow could be achieved via controlled thermal treatment.     

鸡脂肪热氧化与风味的关系

以鸡脂肪为原料,测定脂肪在烹调温度下氧化过程中的羰基值,过氧化值,酸值随加热时间的变化,并以这些测定值为监控指标对不同时间的氧化产物作感官评价。研究结果表明,鸡脂肪氧化能产生较好风味感,并且风味感产生的最佳时间为10 h,此时羰基值为22.5 meq/kg。     

舟山教育学院会议中心AV多媒体系统设计

以舟山教育学院会议中心报告厅AV（音视频）多媒体系统设计为例，具体分析了该AV多媒体系统的组成形式和实现方法，并对AV多媒体技术在教育建设项目设计时需要考虑的一些问题进行了总结。     

Hemodialysis vascular access monitoring: Current concepts

Most arteriovenous grafts fail due to irreversible thrombosis, and most clotted grafts have an underlying stenotic lesion. These observations raise the plausible hypothesis that early detection of graft stenosis with preemptive angioplasty will reduce the likelihood of graft thrombosis. A number of noninvasive methods can be used to detect hemodynamically significant graft stenosis with a high positive predictive value. These tests include clinical monitoring, as well as surveillance by static dialysis venous pressures, flow monitoring, or duplex ultrasound. However, these surveillance tests have a much lower positive predictive value for graft thrombosis in the absence of preemptive angioplasty. In other words, none of the currently available surveillance tests can reliably distinguish between stenosed grafts destined to clot, and those that will remain patent without intervention. As a consequence, any program of graft surveillance necessarily results in a substantial proportion of unnecessary angioplasties. Moreover, a substantial proportion of grafts thrombose despite a normal antecedent surveillance test. Numerous observational studies have found an impressive reduction of graft thrombosis after implementation of a stenosis surveillance program. In contrast, 5 of 6 randomized clinical trials failed to show a reduction of graft thrombosis in patients undergoing graft surveillance, as compared with those receiving only clinical monitoring. The lack of benefit of surveillance is largely attributable to the rapid recurrence of stenosis after angioplasty. Thus, routine surveillance for graft stenosis, with preemptive angioplasty, cannot be recommended for reduction of graft thrombosis. Future research should be directed at pharmacologic interventions to prevent graft stenosis.