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1.
Laboratory experiments were made to examine some characteristics of a radiation thermometer (PRT 14–313, Barnes Engineering
Company). Effect of nonblackness of the water surface and a large temperature difference between the water and the air above
it were investigated.
Sea surface temperatures were then measured by the radiation thermometer, thermistor thermometers and a mercury thermometer
from a marine tower. The result showed that the temperature at the air-sea interface was not always cooler than the subsurface
temperature. The standard deviation of difference of temperatures measured by the radiation thermometer and the thermistor
thermometer was 0.44°C. The dependence of the temperature difference on various factors was investigated with the result that
current velocity had a good correlation with the temperature difference. 相似文献
2.
Thermochains for Black Sea hydrophysical studies are described, and the features of their displacement at the moored buoy station with subsurface buoyancy are considered. A technique for calibrating the temperature sensors is described and their stability is estimated by comparing the obtained calibration coefficients with the values established in previous calibrations. The characteristics of the temperature sensors, including the time constant are specified, as well as their reading error with respect to the reference thermometer. The performed metrological studies prove that the temperature sensors used in the thermochains work rather stably and make measurements with an accuracy of ± 0.01 °C for several months of operation in marine conditions. This allows to determine adequately the temperature at various horizons in the water environment of the shelf-slope zone of the Black Sea and to study not only its short-period, but also long-term variability. 相似文献
3.
为克服温度对溶解氧传感器的影响,对极谱型溶解氧检测系统的溶解氧电极激励源、高精度信号采样、软件标定和温度补偿等方面进行研究。通过对极谱型溶解氧传感器工作原理进行分析,设计了极谱型溶解氧传感器检测电路;根据溶解氧电极的温度特性,设计了基于NTC（负温度系数）热敏电阻的硬件温度补偿电路,并利用最小二乘法及RBF神经网络构建了软件温度补偿模型。利用饱和蒸馏水进行温度补偿实验,结果表明：经温度补偿后,该溶解氧检测系统的相对误差及采样波动均在1%以内,大大减小了传感器的非线性误差,测量精度和稳定性均可满足应用要求。 相似文献
4.
A non-destructive temperature calibration system for expendable bathythermographs (XBT) is described. A transfer standard technique has been used to estimate XBT thermistor probe-to-probe temperature variability. One-point calibration results suggest that a standard deviation of 0.025°C is typical at 10°C. Additional calibration data from nine XBT thermistors suggest that probe-to-probe temperature variability is largest at 0°C (ca. 0.03°C) and decreases uniformly to a minimum at 30°C (ca. 0.01°C). 相似文献
5.
文章依据相关国家标准,结合海洋环境监测站的实际工作需求,针对环境自动观测系统的盐度传感器,提出新的现场校准方法,即直接比较法;根据不确定度来源,分别计算由测量重复性、盐度标准器、测量环境、测量人员和恒温水槽引入的不确定度分量并合成标准不确定度,据此计算扩展不确定度和合成标准不确定度的有效自由度,由此得出盐度传感器现场校准测量结果的不确定度为0.17。本研究提出的盐度传感器现场校准方法更契合海水盐度的变化规律,可实现盐度分量的量值溯源,具有准确度高和溯源途径清晰的特点;不确定度评定方法科学合理,且具有一定的推广价值。 相似文献
6.
潮间带水沙多层位同步测量系统应用的初步研究 总被引：2，自引：0，他引：2
利用水压、光电转换原理研制成的多层位水沙同步测量系统(WCT系统)不仅可测量潮间带水位随时间的变化系列、同一层位的浊度及流速，还可以同步观测这些参数在潮间带水流剖面不同层位上的变化。野外对比试验表明，WCT系统获得的流速值与直读式流速仪的测量结果基本一致，平均相对误差为14．52％；悬沙传感器经野外现场率定获得悬沙浓度，平均相对误差为21．96％，精度比室内率定提高—倍以上。悬沙粒径是影响悬沙浓度测量精度的主要因素。此外，自然环境(如海水温盐度)的变化及仪器本身的特性也可能影响到测量结果。因此，WCT系统在潮间带的水位、流速和悬沙浓度的观测和边界层研究方面有相当潜力。 相似文献
7.
海水温度的测量,是海洋研究中最重要的基本测量之一。所需要的观测精度,通常根据不同的任务和目的而不同。许多情形下能达到±0.1℃已经足够。有时则要求±0.01℃或更高。随着海洋研究和开发的日益发展,迫切需要能有不同精度的可以连续测量、走航直读的数字式测温仪器。目前国内普遍使用的设备尚不能满足这方面的要求。为便于对温度作连续的测量,人们广泛采用性能稳定的铂电阻作感温元件,通过惠斯顿电桥将温度转变成电压信号,由于电桥和铂电阻的非线性,难以给出直读的结果,只好用查鉴定曲线或分段测量等方法。 相似文献
8.
WOCE CTD校准标准和我国的WOCE CTD校准实验室 总被引：3，自引：0，他引：3
对温度、电导率和压力等物理变量的定义、单位，传感器的实验室校准标准和我国在九五863项目中建立的WOCE水平的CTD校准实验室进行了介绍。 相似文献
9.
A procedure is suggested in which a relative calibration for the intensity output of a multibeam echo sounder (MBES) can be performed. This procedure identifies a common survey line (i.e., a standard line), over which acoustic backscatter from the seafloor is collected with multiple MBES systems or by the same system multiple times. A location on the standard line which exhibits temporal stability in its seafloor backscatter response is used to bring the intensity output of the multiple MBES systems to a common reference. This relative calibration procedure has utility for MBES users wishing to generate an aggregate seafloor backscatter mosaic using multiple systems, revisiting an area to detect changes in substrate type, and comparing substrate types in the same general area but with different systems or different system settings. The calibration procedure is demonstrated using three different MBES systems over 3 different years in New Castle, NH, USA. 相似文献
10.
水色遥感是海洋环境监测的主要技术手段之一.对于任何海洋水色遥感器来说,监测其在轨期间的定标系数变化是非常重要的,否则无法得到精确的定量产品.以我国“HY-1B”卫星水色遥感器为研究对象,开展了基于大洋水体上空的瑞利散射定标方法研究,利用通过对SeaWiFS数据叶绿素、离水辐亮度和气溶胶产品进行分析,选择了符合条件的7个海区实施大气瑞利散射定标,根据2010年12月份选定的4个区域定标结果得到不同海区/不同时间获得的定标系数一致性较好,CH1至CH6的定标系数标准差分布在0.9％～2.1％的范围内,因此瑞利散射定标是有效的非现场定标方法,具有较高的定标精度,其总误差在4.09％. 相似文献
11.
负温度系数(negative temperature coefficient,NTC)热敏电阻器由于在窄温区内具有极高的灵敏度,在海洋领域中有着广泛的应用,但深海应用中固有的高静水压力,对器件的测温准确度造成不利影响。为了更好地认识这种现象,以珠状NTC热敏电阻器为研究对象,利用海洋环境高压模拟装置,开展了静水压力作用对器件电学特性影响的研究,固定环境温度25℃和0℃,压力范围0~60 MPa,步长5 MPa。结果显示,随着静水压力的增大,NTC热敏电阻器的电阻值减小;环境温度25℃和0℃时,5~60 MPa的静水压力造成的漂移分别为-0.11%~-2.81%、-0.19%~-2.78%,等效于温度漂移分别为0.024~0.624℃、0.036~0.535℃。这为热敏电阻器在深海温度准确测量的提升提供了指引,有利于在海洋测温领域中更好的应用。 相似文献
12.
The response of an array of sensors to coherent undesired noise interfering with the measurement of a desired signal can be optimized if special filters are applied to the outputs of the sensors. In this paper, we derive analytic expressions for filters which minimize the power spectrum of the array response to the undesired coherent signal while simultaneously providing an all-pass condition for the desired signal. These filters are shown to yield an array rejection response which has zero-width main lobes and no sidelobes. An example illustrating the results is also presented. 相似文献
13.
感应式温盐传感器基于电导率法测盐,可以实现现场测量与实时测量。测量盐度时需要首先计算海水温度、海水电导率和海水压力,表层感应式温盐传感器对压力量不予考虑,温度、电导率的精度却直接关系到盐度测量结果的准确度,因此使用传感器前必须进行温度和盐度的标定。分析了温盐传感器的工作原理,设计温度、电导率的标定校准步骤,包括回归曲线的选择和回归方程系数的计算,其中温度、电导率和温度补偿的标定回归曲线采用多项式形式,用实验室高精度盐度计和铂电阻温度仪测得5~7组数据,然后对多项式最小二乘法回归,电导率回归过程中由温度和盐度求电导率用到了二分法,最后论述了标定回归方程的误差范围。 相似文献
14.
Results are presented from the on-orbit calibration of the Jason Microwave Radiometer (JMR). The JMR brightness temperatures (TBs) are calibrated at the hottest and coldest ends of the instrument's dynamic range, using Amazon rain forest and vicarious cold on-Earth theoretical brightness temperature references. The retrieved path delay values are validated using collocated TOPEX Microwave Radiometer and Radiosonde Observation path delay (PD) values. Offsets of 1–4 K in the JMR TBs and 8–12 mm in the JMR PDs, relative to TMR measurements, were initially observed. There were also initial TB offsets of 2 K between the satellite's yaw state. The calibration was adjusted by tuning coefficients in the antenna temperature calibration algorithm and the antenna pattern correction algorithm. The calibrated path delay values are demonstrated to have no significant bias or scale errors with consistent performance in all nonprecipitating weather conditions. The uncertainty of the individual path delay measurements is estimated to be 0.74 cm ± 0.15, which exceeds the mission goal of 1.2 cm RMS. 相似文献
15.
Jason Microwave Radiometer Performance and On-Orbit Calibration 总被引：2，自引：0，他引：2
Results are presented from the on-orbit calibration of the Jason Microwave Radiometer (JMR). The JMR brightness temperatures (TBs) are calibrated at the hottest and coldest ends of the instrument's dynamic range, using Amazon rain forest and vicarious cold on-Earth theoretical brightness temperature references. The retrieved path delay values are validated using collocated TOPEX Microwave Radiometer and Radiosonde Observation path delay (PD) values. Offsets of 1-4 K in the JMR TBs and 8-12 mm in the JMR PDs, relative to TMR measurements, were initially observed. There were also initial TB offsets of 2 K between the satellite's yaw state. The calibration was adjusted by tuning coefficients in the antenna temperature calibration algorithm and the antenna pattern correction algorithm. The calibrated path delay values are demonstrated to have no significant bias or scale errors with consistent performance in all nonprecipitating weather conditions. The uncertainty of the individual path delay measurements is estimated to be 0.74 cm ± 0.15, which exceeds the mission goal of 1.2 cm RMS. 相似文献
16.
《Oceanic Engineering, IEEE Journal of》2009,34(3):315-322
17.
Akihiko Kuwahara Tsuneyuki Abe Masayuki Shimono Makoto Kashiwai Masatosi Sinoda 《Journal of Oceanography》1973,29(3):106-112
A pump-sampler was designed to study the distribution of marine plankton and its possible relationship with the temperature and salinity of the water. Sea water was pumped up through a 2 inch diameter hose and plankton contained in it was collected on a filter cup (2 inches in diameter, 139 meshes/inch) without being damaged. The filter cup, when clogged by plankton organisms, was washed by spraying with about 100 cu. cm of water. The differences between two continuous with an interval of more than 3–4 seconds could be detected.A preliminary operation along a 2.82 km course in Maizuru Bay was carried out simultaneously with temperature-salinity measurements at sampling intervals of 30 m. Temperature was measured by a thermistor resistance thermometer, and salinity was measured by a salinometer with a subsample of water which was collected from an additional opening of the pump-sampler. The temperature-salinity record showed that four zones of water were characterized.It was found that wide variation of plankton counts indicated dense concentrations of particular species or group of species, and on the mesoscale it was possible to examine the size of the aggregation. 相似文献
18.
海水温盐深剖面测量技术综述 总被引：1，自引：0，他引：1
温盐深是反应海洋物理学特性的重要参数,是海洋水文观测的基本要素。CTD剖面仪(Conductivity-Temperature-Depth profiler)是进行海水温盐剖面观测的主要仪器,利用CTD剖面仪可精确测得水下不同深度上海水的温度和电导率参数,进而能够推算出海水盐度、密度、声速等相关信息,对于海洋经济开发、海上国防建设、海洋环境保护等都具有非常重要的意义。本文介绍了温盐深剖面测量技术的基本原理与发展现状,对几种典型的温盐深测量设备及各种海洋观测平台中搭载的CTD传感器进行了介绍,论述了CTD传感器的标定和测试技术,并对其发展趋势进行了分析。 相似文献
19.
海洋环境参数监测传感器的性能是海洋环境监测参数数据质量的保障。文章以常用的海水温度、电导率、浊度和叶绿素传感器为评估对象,利用同一台仪器连续多年的校准数据实现传感器的稳定性评价。当漂移系数在1附近时,表明传感器性能稳定,当漂移系数大于或小于1时,表明传感器测量值发生漂移;由历年校准数据计算的漂移系数可实现各传感器校准周期内数据的修正,修正前各传感器的测量误差大且呈单向增量变化,修正后的误差降至传感器最大允许误差且呈正态分布。利用历史计量数据建立的传感器性能评价模型可为用户提供长期的传感器稳定性评价,有利于提升海洋环境监测传感器的性能和数据的准确性,拓展计量数据的服务能力。 相似文献
20.
J.-G. Dessureault 《Ocean Engineering》1976,3(2):99-111
“Batfish” is a streamlined vehicle developed to house fast-responding oceanographic sensors. It is towed behind a ship or small vessel and its depth is controlled from the vessel by a manually or automatically produced command signal. Variable-angle wings permit the vehicle to be lowered and a novel control surface, which eliminates the need for heavy ballast, assures lateral stability. There are two models: the standard and the wide-wing Batfish. The standard Batfish has collected temperature and conductivity data at depths of up to 200 m when towed at 10–25 km/hr, and the wide-wing Batfish at depths to 400 m when towed at 10–16km/hr. 相似文献