保偏光纤起偏器消光比偏振敏感性的实验研究

本文采用了 180°输入测量的新方法研究了保偏光纤起偏器消光比随着输入线偏振光偏振方向变化规律。并对其进行了相应的讨论与分

Symbol Timing Rapid Acquisition Algorithm for π/4-DQPSK and Implementation of DSP

阐述利用一种新的π 4 -DQPSK调制快速位定时捕获算法进行低速率数字移动突发通信 ,并利用TMSC5 4xDSP芯片实现该算法的关键技术。实验表明 ,该算法能够更加有效地克服多普勒频移并快速实现位定时捕获A new symbol timing rapid acquisition algorithm for π/4-DQPSK in low-rate digital mobile burst signal communication is elaborated.DSP-based implementation is also presented.Compared with traditional algorithms,the experimental results with new algorithm show that Doppler frequency offset can be avoided effectively and symbol timing rapid acquisition process can be completed rapidly

Investigation on the iodine status among the population in rural and urban areas of Xiamen in 2013

目的了解碘盐新标准实施后农村和城市人群的碘营养现况,为有效落实科学补碘防控策略提供依据。方法在农村和城市调查点各抽取1个镇的1个村,在每个村采集自来水厂出厂水和末梢水各2份;抽取30户以上居民,采集各户家庭食用盐,用3日称量法测算各户居民人均食盐摄入量;抽取18-45岁成人50名以上,采集尿样。在抽中的镇随机选择8-10岁儿童(男女各半)、孕妇和哺乳期妇女各50名以上,采集尿样。测定盐碘、尿碘和水碘含量。结果农村和城市自来水末梢水水碘含量均值分别为4.5μg/L和6.0μg/L;居民人均每日食用盐摄入量中位数分别为7.0和5.6g;8~10岁儿童尿碘中位数分别为152.0和181.2μg/L;哺乳妇尿碘中位数分别为108.3和107.7μg/L;18-45岁成人尿碘中位数分别为121.1和147.4μg/L;孕妇尿碘中位数分别为116.0和112.2μg/L,尿碘含量低于150μg/L的比例分别达67.9%和64%;除农村人均每日食用盐摄入量高于城市,农村18-45岁成人尿碘水平低于城市外,其他指标农村和城市间差异无显著性。结论厦门市仍是缺碘地区,在现有碘盐标准下,8-10岁儿童、18-45岁成人、哺乳期妇女的碘营养处于适宜水平,但孕妇的碘营养不足,要开展针对孕期人群的碘营养监测和指导,杜绝碘缺乏所造成的危害。Objective To gain knowledge of the iodine status among the population in rural and urban areas after the implement of new standard for edible salt and to provide scientific evidence for the initiative of the iodine supplement strategy. Method 1 village / community was selected randomly from rural and urban area as research site respectively. 2 samples of treated water and tap water were collected respectively in both sites, 30 + houses were enrolled randomly and edible salt samples were collected. 3days weighed record was employed to estimate average salt daily intake. Urine sample was collected from 50 + adults aged from 18 to 45. Identical sample was also collected from 50 + children aged from 8 to 10( same amount of subjects in both genders),pregnant women, and lactating women respectively. Iodine level of water, salt, and urine was determined by laboratory assay.Results The iodine concentration of tap water in rural and urban areas was 4. 5 μg / L and 6. 0 μg / L,respectively. The median of average iodine intake in rural and urban areas was 7. 0 g and 5. 6 g, respectively. The median in urine iodine was 152. 0 μg / L and 181. 2 μg / L,respectively. This measurement in lactating women was 108. 3 μg / L and 107. 7 μg / L,respectively. And it was121. 1 μg / L and 147. 4 μg / L in adults aged 18 to 45, respectively. As for the pregnant women, the iodine level reached 116. 0μg /L and 112. 2 μg /L,respectively. The proportion of subjects has urine iodine level less than 150 μg /L reached 67. 9 % and 64 %, respectively. The average salt intake in rural area was higher than urban significantly, and the urine iodine level in adults aged 18 to 45 from rural area was significantly lower than urban. No significance was found in other comparison. Conclusion Through our investigation,Xiamen is still an iodine deficiency area. Under the implement of new edible salt standard, the iodine status in children aged 8 to 10, adults aged 18 to 45 and lactating women was adequate, however, we found that pregnant women enrolled in our study have iodine deficiency in some degrees. Therefore the iodine surveillance and dietary guidance should be performed among pregnant women to eliminate the harm caused by iodine deficiency

TT病毒与肝炎关系的临床流行病学研究

目的　对闽南地区各种肝炎患者、健康体检者、义务献血员和肝癌患者共480例从临床流行病学角度探讨TT病毒(TTV)的致病性及其与各种肝炎的关系。方法　采用巢式PCR检测血清TTVDNA、ELISA检测血清抗HAVIgM、HBsAg、抗HBcIgM、抗HCVIgG、抗HEVIgG,用EPIINFO60软件进行统计分析。结果　480名研究对象中TTVDNA的总检出率为23.96%。各种肝炎患者的TTV总阳性率为2394%,肝癌患者的TTV阳性率为2069%,而健康者的TTV阳性率为2484%,义务献血员的阳性率为3000%,均未见明显差别。从临床类型看,急性肝炎、慢性肝炎和重症肝炎的TTV阳性率都在25%左右;从病原类型看,非甲～戊型肝炎的TTV阳性率为2619%,并未见与相应健康者的2523%阳性率的差别;除HCV由于感染率太低而无法分析外,HAV、HBV、HEV阳性肝炎患者间TTV的阳性率分别为2000%、2314%、2179%,未见TTV与这些已知肝炎病毒的明显相关。对一个时期内的全部135例住院肝炎患者及153名健康者进行肝炎病原分析,HAV、HBV、HEV在肝炎患者中的阳性率都要明显高于健康人(P=00142),而TTV在肝炎患者中的阳性率与健康人没有明显差别(P=06021);对病毒的单独致病性进行分析,HAV、HBV、HEV在非重叠感染的肝炎患者中的阳性率都要明显高于健康人(P=00037),而TTV在非甲～戊型肝炎患者中的

Research on Practical Applications of Optical Fiber Current Sensors

本文详细阐述了光纤电流传感器的原理、应用。对应用高圆双折射光纤的电流传感器进行了研究，在传统的信号处理方案上，保留其原方案优点，提出新的功率补偿方案，对应用高圆双折射光纤电流传感器的温度效应进行研究。在理论上进行了各种条件下的模拟计算，并在实验中加以验证。实验表明高圆双折射光纤的电流传感器的线性度很好，功率补偿方案效果明显，温度补偿方案具有一定的效果。 对普通光纤电流传感效应，本文也进行了有益的研究，并进行了相关的理论计算和实测。本文还引入了一个新的概念：光系统的共模抑制比，用以衡量双路输入系统抑制外界干扰的能力。 利用全光纤器件构成全光纤电流传感器，在厦门大学电子工程系进行了长时间的实际...This thesis presents both the theory and the application of fiber optic current sensors in detail. Electric current sensors employing highly circularly birefringent fiber are proposed. Also a novel scheme to compensate for laser source power and ambient temperature fluctuation is proposed here. This scheme is based on the traditional signal-processing scheme with simpler and more effective design....学位：理学硕士院系专业：计算机与信息工程学院电子工程系_无线电物理学号：19993000

“中国光谷”之路的思考

光电子技术是一国信息化和现代化的基础条件之一,对一个国家的经济建设、社会变革、国家安全乃至整个社会发展起着难以估量的关键作用。目前,世界光电子产业正处在一个极为活跃的发展期和极为关键的转折期,在此背景下,我国“光谷热”骤然升温。与发达国家相比,我们的差距主要表现在技术成果的转化和产业化方面。本文就此对“中国光谷”的发展道路提出若干建议

双混合室新型萃取箱研究成果简报

1982年12月10—11日,冶金工业部和中国科学院在京联合召开了双混合室新型萃取箱半工业试验成果鉴定会。冶金部有色局、科学院化学部有关领导同志出席了开幕式,并讲了话。对由金川有色金属公司、科学院化冶所和北京有色冶金设计研究总院等三个单位密切合作,在较短的时间内取得较好试验结果给予了充分肯

双混合室新型萃取箱的研究

为了发展我国的萃取设备,我们运用流体力学原理和结合国情,于1979年底开始研制双混合室萃取箱(下称双室萃取箱)及其配用搅拌器,三年来做了箱体结构、搅拌

高可靠性PIN光电探测器底座封装技术

PIN探测器因其响应速度快,约10~(-7)秒;低偏压下漏电流低,约在10~(-10)A数量级;响应频带宽等诸多优点在光纤通信、光纤传感等领域应用广泛。但是日前已用的PIN探测器普遍存在一个缺点:由于其封装的引脚纤细,使用可靠性较差,不易焊接,加之PIN探测器价格昂贵,如何设计高可靠性的封装已经成为亟待解决的问题

Dependable Package Technology of PIN Photodetector Base

针对PIN探测器易损坏、焊接等场合使用不便之缺点 ,提出一种新型高可靠性的探测器底座封装技术。实测特性表明 ,应用这种封装不仅没有降低PIN探测器性能 ,反而大大加强了探测器应用的牢固性。The PIN diode is vulnerable to be damaged during application such as being welded to circuits.In this paper a novel package technology to protect PIN base is proposed.Practical application shows that this type of package is of great advantage to dependability