New Development in the Performance Improvement Synchronous Motor

Synchronous machines are dedicated to the specific application. They are generally employed in rolling mills, pumps, fans, and compressors like reprobating and centrifugal drives, pulp and paper processing, water treatment, mining, and in cement industries. As a synchronous motor, the performance is reduced for the given excitation while the load increases. When operated as synchronous generators, both power loads and lighting loads depend on the output from the armature winding. This paper presents an alternative choice in which by providing an additional winding in the stationary armature, when operated as a Double Winding Synchronous Motor (DWSyM), it becomes possible to operate in maximum power factor by adjusting the loads on both the stator windings. When operated as conventional motor, for the load current of 3.5 A, the efficiency is 55% and power factor is 0.55, for the same excitation when second winding is connected to a load current of 1 A, the efficiency is improved to 77.6% and power factor is improved to 0.66. The main focus of this machine is to improve the performance of the machine for the reduced excitation and minimum load. For the reduced excitation, the performance can be improved by loading both the windings. While operated as Double Winding Synchronous Generator (DWSyG), two stator outputs are available which help to separate the power and lighting circuits. Hence, interruption in the lighting circuit can be limited, this machine can be considered as Twin generator.

结核病的性别差异:南印度某农村地区DOTS项目报告

背景:南印度 Tiruvallur 地区。目的:了解 14 岁以上成年人在结核感染和患病、就医途径、就医行为、诊断延误、接受 DOT的方便程度、疾病歧视以及治疗依从性等方面的性别差异。方法:相关数据主要来自:1)社区调查,2)在公立初级保健卫生机构(PHIS)主动就医的病人,3)转诊到 PHIS 进行痰涂片检查的可疑结核病人;4)DOTS 策略下的登记报告结核病人。并将社区调查结果与 PHIS 登记病人进行比较。结果:社区人群中 66%的男性和 57%的女性感染了结核菌;男性和女性的涂阳肺结核患病率分别为568/10 万和87/10 万。在 PHIS 就医的男性少于女性,男女之比为 68:100。女性占社区调查发现涂阳病人的 13%;占 PHIS 发现病人的 20%(P<0.05)。随着年龄的增长,男性和女性的登记率显著降低。女性感觉难于与家人讨论自己病情的比例要高于男性(21%∶14%),也更需要有人陪伴去接受 DOT(11%∶6%)。男性的治疗中断率比女性高 1 倍(19%∶8%;P<0.01)。结论:尽管女性发病后更容易遭受歧视和不便,但女性更易于利用医疗服务、接受 DOTS 策略登记以及依从治疗。而男性以及高龄病人在诊断和 DOT服务方面更需要帮助。

在印度门诊病人中比较咳嗽2周与3周为痰检筛选标准对提高涂阳结核病例发现的效果

背景﹕印度六个区的政府卫生机构。目的﹕估算咳嗽的发生率及比较咳嗽≥2周或≥3周的门诊病人涂阳结核病的发现情况。设计﹕由经过培训的卫生人员询问每一病人的咳嗽情况,咳嗽≥2周者进行痰显微镜检查。结果﹕在调查的55561例门诊病人中,咳嗽≥2周者2210例(4%),其中267例为涂阳结核病,而咳嗽≥3周者则为182/1370。31%病人无咳嗽主诉,涂阳可能性显著低于有咳嗽主诉者(各为45/680[7%]、222/1530[15%],P<0.001)。但在267例涂阳病人中占45例。如以咳嗽≥2周为痰显微镜检查筛选标准,估计在初级、二级卫生机构每天进行涂片检查各为8次与19次,如以咳嗽≥3周为标准则各为5次及12次。结论﹕认真询问门诊病人的咳嗽情况以及将咳嗽≥3周改为≥2周作为痰检的筛选标准可以显著提高涂阳结核病人的发现。但在全国实施此改变前需对其进行规划可行性评估。