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91.
92.
Requirements for monitoring the coastal zone environment are first summarized. Then the application of hyperspectral remote sensing to coast environment investigation is introduced, such as the classification of coast beaches and bottom matter, target recognition, mine detection, oil spill identification and ocean color remote sensing. Finally, what is needed to follow on in application of hyperspectral remote sensing to coast environment is recommended. 相似文献
93.
4种微生态制剂对对虾育苗水体主要水质指标的影响 总被引:6,自引:1,他引:5
研究了由球形红假单胞菌(Rhodopseudomlonas sphaeroides)、噬菌蛭弧菌(Bdellovibrio bacteriovorus)及黏红酵母(Rhodotorula glutinis)制成的4种微生态制剂对中国对虾(Fenneropenaeus chinensis)育苗水质的影响.结果表明,试验组与对照组相比都能明显净化水质,试验组中以添加噬菌蛭弧菌和黏红酵母组的效果最差,添加球形红假单胞茵和噬茵蛭弧茵组的效果最好,此组水质的pH值稳定,NH4+-N明显下降,而亚硝酸盐、化学需氧量及硫化物等指标也优于其他试验组.统计分析显示,试验组与对照组相比,细菌数降低了3个数量级,添加嗜菌蛭弧菌试验组在减少异养茵(包含有害细菌)方面效果较好.同时用鳗弧菌攻毒,在5 d内,对照组的死亡率显著高于试验组(P<0.05),试验组免疫保护率为29.4%~58.5%,以添加嗜菌蛭弧菌和球形红假单胞菌组最高.建议联合使用噬菌蛭孤菌和球形红假单胞菌,混合密度初步定为2×105个/mL. 相似文献
94.
95.
The tracking control problem of AUV in six degrees-of-freedom (DOF) is addressed in this paper. In general, the velocities of the vehicles are very difficult to be accurately measured, which causes full state feedback scheme to be not feasible. Hence, an adaptive output feedback controller based on dynamic recurrent fuzzy neural network (DRFNN) is proposed, in which the location information is only needed for controller design. The DRFNN is used to online estimate the dynamic uncertain nonlinear mapping. Compared to the conventional neural network, DRFNN can clearly improve the tracking performance of AUV due to its less inputs and stronger memory features. The restricting condition for the estimation of the external disturbances and network's approximation errors, which is often given in the existing literatures, is broken in this paper. The stability analysis is given by Lyapunov theorem. Simulations illustrate the effectiveness of the proposed control scheme. 相似文献
96.
Reversible protein phosphorylation, catalyzed by protein kinases and phosphatases, is an important and versatile mechanism by which eukaryotic cells regulate almost all the signaling processes. Protein phosphatase 1 (PP1) is the first and well-characterized member of the protein serine/threonine phosphatase family. In the present study, a full-length cDNA encoding the beta isoform of the catalytic subunit of protein phosphatase l(PPlcb), was for the first time isolated and sequenced from the skin tissue of flatfish turbot Scophthalmus maximus, designated SmPPlcb, by the rapid amplification of cDNA ends (RACE) technique. The cDNA sequence of SmPPlcb we obtained contains a 984 bp open reading frame (ORF), flanked by a complete 39 bp 5' untranslated region and 462 bp 3' untranslated region. The ORF encodes a putative 327 amino acid protein, and the N-terminal section of this protein is highly acidic, Met-Ala-Glu-Gly-Glu-Leu-Asp-Val-Asp, a common feature for PP1 catalytic subunit but absent in protein phosphatase 2B (PP2B). And its calculated molecular mass is 37 193 Da and pI 5.8. Sequence analysis indicated that, SmPPlcb is extremely conserved in both amino acid and nucleotide acid levels compared with the PPlcb of other vertebrates and invertebrates, and its Kozak motif contained in the 5'UTR around ATG start codon is GXXAXXGXXATGG, which is different from mammalian in two positions A6 and G3, indicating the possibility of different initiation of translation in turbot, and also the 3'UTR of SmPPlcb is highly diverse in the sequence similarity and length compared with other animals, especially zebraf'lsh. The cloning and sequencing of SmPPlcb gene lays a good foundation for the future work on the biological functions of PP1 in the flatfish turbot. 相似文献
97.
东营凹陷南斜坡沙四段高频沉积旋回对滩坝砂体的沉积控制作用 总被引:1,自引:0,他引:1
在东营凹陷南斜坡的沙四段地层中,常发育典型的湖相滩坝砂体沉积.详细观察表明,这些滩坝砂体在垂向上常发育较为对称的高频基准面上升半旋回和下降半旋回,且对滩坝砂体的沉积过程有明显的控制作用.通过测井曲线的频谱分析,高频基准面的变化与米兰柯维奇轨道气候周期有着密切的关系,而单砂体规模的滩坝砂体在平面展布上又有着明显的对称性.这些都表明滩坝砂体主要沉积在湖平面升降转换的相对稳定期,同生断层活动产生的陡坎或隆起会有助于滩坝砂体的富集.可根据滩坝砂体的垂向沉积序列和组合方式来判断滩坝主体的分布位置. 相似文献
98.
1 “大海之子”
2005年的1月20日,为中国和世界海洋科学事业奋斗了76年、96岁的“大海之子”——中国科学院资深院士曾呈奎先生带着他实施海洋开发战略的种种思考与世长辞了。而在此前一个月,在曾呈奎先生弥留之际,由他担任总主编的435万字的巨著——《中国现代海洋科学丛书》由山东教育出版社隆重推出。科学巨星陨落,令人痛惜;鸿篇巨制面世,又令人振奋,使人不禁更加怀念曾呈奎先生。 相似文献
99.
It is well known that pitting corrosion occurring on surface of hull structural plate will surely result in a significant degradation of the ultimate strength of the hull structural plate. This report aims at development of an assessing formula for ultimate strength of hull plate with pitting corrosion damage under the biaxial in-plane compression loading. The ultimate strength assessment model that is in terms of the corroded volume loss was deduced in theory, and which was then completed through numerical experiment by employing nonlinear finite element analyses for series of corroded plate models. Meanwhile, pitting corrosion in actual ship hull was analyzed and simulated, which ensured that all the assumptions for the finite element model parameters were in accord with the actual hull plate with pitting corrosion damage. Furthermore, the effects of plate slenderness, the linear factors at the plate edges and the ratio between the transverse and the longitudinal in-plane stresses on the ultimate strength reduction related to the corroded volume loss were discussed. The ultimate strength assessment formula being in terms of corroded volume loss developed in this research is expected to be applicable to assess the ultimate strength of the hull structural plate with pitting corrosion damage. 相似文献
100.
This paper proposes a scheme of axial triple-well optical dipole trap by employing a simple optical system composed of a circular cosine grating and a lens. Three optical wells separated averagely by ~37 μm were created when illuminating by a YAG laser with power 1 mW. These wells with average trapping depth ~0.5 μK and volume ~74 μm3 are suitable to trap and manipulate an atomic Bose--Einstein condensation (BEC). Due to a controllable grating implemented by a spatial light modulator, an evolution between a triple-well trap and a single-well one is achievable by adjusting the height of potential barrier between adjacent wells. Based on this novel triple-well potentials, the loading and splitting of BEC, as well as the interference between three freely expanding BECs, are also numerically stimulated within the framework of mean-field treatment. By fitting three cosine functions with three Gaussian envelopes to interference fringe, the information of relative phases among three condensates is extracted. 相似文献