Generalised measures of reliability for multiple outliers

The application of the theory of reliability has become a fundamental part of measurement analysis, whether in order to optimise measurement systems so that they are resistant to the influence of outliers or in the post-analysis identification of outliers. However, the current theory of reliability is based on the assumption of a single outlier—an assumption that may not necessarily be the case. This paper extends reliability theory so that it can be applied to multiple outliers through the derivation of appropriate measures of reliability for multiple outliers. The measures of reliability covered include minimal detectable biases, reliability numbers, controllability, and external reliability.     

Integrated GPS/INS navigation system with dual-rate Kalman Filter

A dual-rate Kalman Filter (DRKF) has been developed to integrate the time-differenced GPS carrier phases and the GPS pseudoranges with INS measurements. The time-differenced GPS carrier phases, which have low noise and millimeter measurement precision, are integrated with INS measurements using a Kalman Filter with high update rates to improve the performance of the integrated system. Since the time-differenced GPS carrier phases are only relative measurements, when integrated with INS, the position error of the integrated system will accumulate over time. Therefore, the GPS pseudoranges are also incorporated into the integrated system using a Kalman Filter with a low update rate to control the accumulation of system errors. Experimental tests have shown that this design, compared to a conventional design using a single Kalman Filter, reduces the coasting error by two-thirds for a medium coasting time of 30?s, and the position, velocity, and attitude errors by at least one-half for a 45-min field navigation experiment.     

1988年至1995年IERS天球参考架的指向维持

本文分析了１９９２年至１９９５年期间国际地球自转服务（ＩＥＲＳ）天球参考架的指向维持情况，结合１９８８年至１９９２年的指向维持情况指出，该参考架在１９８８年至１９９５年期间历年的指向均存在显著变化，赤经零点和天极的最大年度漂移约为０．４ｍａｓ。至１９９５年，ＩＥＲＳ天球参考架的赤经零点和天极与各自预期位置的偏差不于０．４ｍａｓ。１９９４年和１９９５年的ＩＥＲＳ天球参考架基本上维持了１９９３年的ＩＥＲＳ天球参考指向，但是其实际维持精度约为０．０５ｍａｓ，并非０．００５ｍａｓ。０．００５ｍａｓ的维持精度只是数学上的平均效果，相当一部分基本源在相邻年度的ＩＥＲＳ天球参考架中的坐标差大于０．５ｍａｓ，这说明只有采用恰当的消除局部相对形变的方法，才能将天球参考架的指向真正维持在较高水平。     

天球参考系实现中的问题评述

本文评述了在建立历表参考架和恒星参考架过程中所面临的问题和困难，回顾了建立河外射电天球参考架的发展历史，并介绍了其目前状况，讨论了河外射电天球参考架在与其他天球参考架连接过程中所遇到的问题及其可能的解决途径。     

河外射电源在IERS综合表与观测表中坐标差的特性分析

本文简要介绍了ＩＥＲＳ综合河外射电源表在所用资料、建立方法等方面的一般情况，进而分析了河外射电源在ＩＥＲＳ综合表与观测表中的坐标差的一般特性，为检验综合表提供了分析基础。     

1988至1992各年度IERS综合河外射电源表的重新归算

鉴于ＩＥＲＳ综合河外射电源表在建立ＩＡＵ协议天球参考架方面的重要意义和它们的不足之处，本文重新组建了１９８８至１９９２各年度的综合河外射电源表，称之为Ｃａｔ系列表。并依据综合表的组建原理，对重新计算得到的Ｃａｔ系列表进行了检验，结果表明Ｃａｔ系列表克服了ＩＥＲＳ系列表中坐标系不统一的缺点，指向的定义及维持亦较之ＩＥＲＳ系列表有较大程度地改观。比较结果显示，ＩＥＲＳ系列表中部分源的坐标存在毫角秒量级的偏差，各年度综合表的指向与ＩＥＲＳ预期指向亦有不同程度的偏离，个别轴的最大指向偏差至０．６ｍａｓ。同时指出，１９９３年ＩＥＲＳ综合表的指向亦有待讨论。     

Seasonal variation of biochemical components in clam (<Emphasis Type="Italic">Saxidomus purpuratus</Emphasis> Sowerby 1852) in relation to its reproductive cycle and the environmental condition of Sanggou Bay,China

Seasonal variation of biochemical components in clam (Saxidomus purpuratus Sowerby 1852) was investigated from March 2012 to February 2013 in relation to environmental condition of Sanggou Bay and the reproductive cycle of clam. According to the histological analysis, the reproductive cycle of S. purpuratus includes two distinctive phases: a total spent and inactive stage from November to January, and a gametogenesis stage, including ripeness and spawning, during the rest of the year. Gametes were generated at a low temperature (2.1°C) in February. Spawning took place once a year from June to October. The massive spawning occurred in August when the highest water temperature and chlorophyll a level could be observed. The key biochemical components (glycogen, protein and lipid) in five tissues (gonad, foot, mantle, siphon and adductor muscle) were analyzed. The glycogen content was high before gametogenesis, and decreased significantly during the gonad development in the gonad, mantle and foot of both females and males, suggesting that glycogen was an important energy source for gonad development. The protein and lipid contents increased in the ovary during the gonad development, demonstrating that they are the major organic components of oocytes. The lipid and protein contents decreased in the testis, implying that they can provide energy and material for spermatogenesis. The results also showed that protein stored in the mantle and foot could support the reproduction after the glycogen was depleted.     

微波与光学遥感协同反演旱区地表土壤水分研究

土壤水分是水文循环中的关键因素,尤其对旱区的生态环境具有十分重要的意义。微波遥感是反演土壤水分的有效手段,而植被是影响土壤水分反演精度的重要因素。因此,对土壤水分的反演需要考虑植被的影响。本文以内蒙古乌审旗为研究区,利用Radarsat-2雷达数据与TM光学数据,对旱区稀疏植被覆盖地表土壤水分反演进行研究。利用TM数据,分别选取NDVI和NDWI指数对植被含水量进行反演,通过水云模型消除植被层对土壤后向散射系数的影响;在此基础上,根据研究区地表植被特性,提出一种基于AIEM 模型的反演土壤水分的改进算法,反演了不同粗糙度参数、不同极化（VV极化和HH极化）条件下的研究区土壤水分。反演结果与野外实测数据的对比结果表明,本文提出的基于地表植被特性的土壤水分改进算法,具有更好的适应性;土壤水分反演模式\begin{array}{c}M{v}_{\mathit{\sigma vv}\left(1\right)}^{\mathit{lh}}\end{array}（VV极化方式下采用NDVI去除植被影响的反演模式）更适合于旱区考虑稀疏植被覆盖影响的地表土壤水分的反演。     

Production of polyhydroxybutyrate by the marine photosynthetic bacterium Rhodovulum sulfidophilum P5

The effects of different NaCl concentrations, nitrogen sources, carbon sources, and carbon to nitrogen molar ratios on biomass accumulation and polyhydroxybutyrate (PHB) production were studied in batch cultures of the marine photosynthetic bacterium Rhodovulum sulfidophilum P5 under aerobic-dark conditions. The results show that the accumulation of PHB in strain P5 is a growth-associated process. Strain P5 had maximum biomass and PHB accumulation at 2%-3% NaCl, suggesting that the bacterium can maintain growth and potentially produce PHB at natural seawater salinity. In the nitrogen source test, the maximum biomass accumulation (8.10±0.09 g/L) and PHB production (1.11±0.13 g/L and 14.62%±2.25% of the cell dry weight) were observed when peptone and ammonium chloride were used as the sole nitrogen source. NH 4 + -N was better for PHB production than other nitrogen sources. In the carbon source test, the maximum biomass concentration (7.65±0.05 g/L) was obtained with malic acid as the sole carbon source, whereas the maximum yield of PHB (5.03±0.18 g/L and 66.93%±1.69% of the cell dry weight) was obtained with sodium pyruvate as the sole carbon source. In the carbon to nitrogen ratios test, sodium pyruvate and ammonium chloride were selected as the carbon and nitrogen sources, respectively. The best carbon to nitrogen molar ratio for biomass accumulation (8.77±0.58 g/L) and PHB production (6.07±0.25 g/L and 69.25%±2.05% of the cell dry weight) was 25. The results provide valuable data on the production of PHB by R. sulfidophilum P5 and further studies are on-going for best cell growth and PHB yield.     

GPS and GLONASS Integration: Modeling and Ambiguity Resolution Issues

The integration of GPS with GLONASS may be considered a major milestone in satellite-based positioning, because it can dramatically improve the reliability and productivity of said positioning. However, unlike GPS, GLONASS satellites transmit signals at different frequencies, which result in significant complexity in terms of modeling and ambiguity resolution for integrated GPS and GLONASS positioning systems. In this paper, a variety of mathematical and stochastic modeling methodologies and ambiguity resolution strategies are analyzed, and some remaining research challenges are identified. The exercise, of developing mathematical models and processing methodologies for integrated systems based on more than one satellite system, is a valuable one as it identified crucial issues concerned with the combination of any two or more microwave positioning systems, be they satellite-based or terrestrial. Hence these are experiences that can be applied to future projects that might integrate GPS with Galileo, or GLONASS and Galileo, or all three. ? 2001 John Wiley & Sons, Inc.