Encapsulated sodium supplementation of 4 weeks does not alter salt taste preferences in a controlled low sodium and low potassium diet

Preference for saltiness is learned by oral exposure to salt taste; however, some data suggest a role for bodily sodium and potassium levels on salt taste preferences as well. The objective was to investigate whether encapsulated sodium and potassium supplementation lead to altered salt taste responses among adults with high blood pressure on a low sodium and low potassium diet. Twenty-six participants with untreated upper-range prehypertension or stage 1 hypertension were on a fully controlled low sodium and low potassium diet (both targeted at 2 g/day) for 13 weeks. Participants received capsules with sodium (3 g/d), potassium (3 g/d), or placebo, for 4 weeks each, in randomized order in a double blind crossover design. Sensory evaluation was done before and after each supplementation period and involved ratings of pleasantness and intensity in different salt (NaCl) concentrations in food and water, desire-to-eat salty food, and detection threshold for NaCl. Neither sodium supplementation nor potassium supplementation led to alterations in salt taste responses in food and water, and did not affect detection threshold (P = 0.59). There was no clear role for sodium or potassium supplementation on desire-to-eat salty food. In addition, we did not find effects of reduced oral exposure to salt over weeks, through the sodium-reduced diet, on salt taste preferences, in contrast to earlier studies. In conclusion, the results of this study suggest preference for saltiness is independent of changes in bodily sodium or potassium levels.     

Survey on Passivity Based Control of Induction Machine

Induction machines (IM) constitute a theoretically interesting and practically important class of nonlinear systems. They are frequently used as wind generators for their power/cost ratio. They are described by a fifth‐order nonlinear differential equation with two inputs and only three state variables available for measurement. The control task is further complicated by the fact that IM are subject to unknown (load) disturbances and the parameters can be of great uncertainty. One is then faced with the challenging problem of controlling a highly nonlinear system, with unknown time‐varying parameters, where the regulated output, besides being unmeasurable, is perturbed by an unknown additive signal. Passivity‐based control (PBC) is a well‐established structure‐preserving design methodology which has shown to be very powerful to design robust controllers for physical systems described by Euler‐Lagrange equations of motion. PBCs provide a natural procedure to "shape" the potential energy yielding controllers with a clear physical interpretation in terms of interconnection of the system with its environment and are robust vis á vis to unmodeled dissipative effects. One recent approach of PBC is the Interconnection and Damping Assignment Passivity‐Based Control (IDA‐PBC) which is a very useful technique to control nonlinear systems assigning a desired (Port‐Controlled Hamiltonian) structure to the closed‐loop. The aim of this paper is to give a survey on different PBC of IM. The originality of this work is that the author proves that the well known field oriented control of IM is a particular case of the IDA‐PBC with disturbance.     

新安江电站进水口快速闸门动水闭门鉴定试验

本文叙述了应用现代科学方法和实验原型观测技术对新安江水电站进水口快速闸门进行安全检测鉴定，并介绍了水电站快速闸门动水闭门试验程序，对水电站快速闸门试验及相关鉴定有重要参考意义。     

基于CB的串行口和接口板端口程序应用

串行口及接口板端口是计算机通信的主要途径 ,也是目前计算机工程测控中通用的基本方法。C Builder (简称CB)编程语言以其功能完备、开发效率高的特点而成为目前流行的程序开发工具 ,介绍了利用CB语言编写串行口和端口通信的程序的方法 ,并对具体的各方法编写了相应的示例。     

马家河水电站的设计

马家河水电站通过在马家河和毛家河上游分别建底栏栅坝和低拱坝 ,经各自的引水系统将水引至两河口汇合流入前池发电。本文介绍了电站的开发方案 ,厂区、引水工程和取水枢纽的布置和设计     

竖井式跌水在尚希庄水库进水口设计中的应用

本文介绍了竖井式跌水在尚希庄水库进水口设计中的应用,提出按过流能力相适应的原则设计竖井尺寸,按消能池中形成淹没式水跃的原则设计池深。     

贵阳市北供电局配网自动化系统的通信方式

分析了配网自动化通信的地位和作用，对各种通信方式进行了比较，介绍了贵阳市北供电局的酿网自动化通信方案及实施情况。     

Windows 95/98环境下PC机并行打印端口控制步进电机的研究

介绍了在Windows95／98环境下利用IBM-PC机打印端口控制步进电机运动的实现方法，并给出了关键程序的实现代码。     

静压滑环及其应用研究

 介绍了静压滑环的结构特点及其应用． 通过比较静压轴承、配流盘和静压滑环三者之间的不同点，得出静压滑环在结构上是一个自平衡元件，在功能上类似于电刷滑环，因此在固定件和旋转件之间进行流体动力传输时，静压滑环是理想的选择．     

实施取水定额管理的几个关键问题探讨

通过对全国23个省级单位出台的用水定额标准进行分析，指出目前定额管理存在6个主要问题：一是概念模糊，二是制定方法不统一、不规范，三是定额标准体系不完善，四是可操作性较差，五是计量系统不完善，六是缺乏取水定额管理信息化平台。提出应采用“取水定额”这一表述，并提出了取水定额的体系，包括基础计量体系、定额制定体系、信息链体系、定期更新体系4部分。明确了取水定额管理体系建设主要内容应包括：法律法规体系、定额制定体系、水价管理体系、信息通道体系。