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951.
Zebrafish is a useful animal model for studying human diseases such as muscle disorders. However, manual monitoring of fish motion is time-consuming and prone to subjective variations. In this paper, an automatic fish motion analytics framework is proposed. The proposed framework could be exploited to help validate zebrafish models of transgenic zebrafish that express human genes carrying mutations which lead to muscle disorders, thus affecting their ability to swim normally. To differentiate between wild-type (normal) and transgenic zebrafish, the proposed framework consists of two approaches to exploit discriminative spatial–temporal kinematic features which are extracted to represent zebrafish movements. First, the proposed approach studies precise quantitative measurements of motor movement abnormalities using a camera with the capability to record videos with high frames rates (up to 1,000 frames per second). This differs from previous works, which only tracked each fish as a single point over time. Second, the proposed approach studies multi-view spatial–temporal swimming trajectories. This differs from previous works which typically only considered single-view analysis of fish swimming trajectories. The proposed motion features are then incorporated into a supervised classification approach to identify abnormal fish movements. Experimental results have shown that the proposed approach is capable of differentiating between wild-type and transgenic zebrafish, thus helping to validate the zebrafish models.  相似文献   
952.
经济的发展加快了城市建设步伐,建筑业也乘此时机获得了繁荣的发展,经济的发展与居民收入的增加加剧了对建筑的需求量,对建筑物的结构设计与安全质量等也提出了更具挑战性的要求。在这种客观形势下,必须加强工民建筑结构设计。  相似文献   
953.
954.
Beam lifetime of a synchrotron is dominated by Touschek scattering.In the beamline Phase Ⅱ project of Shanghai synchrotron radiation facility,a passive third harmonic cavity is to be installed for bunch lengthening and instability suppressing.In this paper,the beam dynamics of the cavity is investigated.The parameters of passive operation are optimized to cancel the slope of RF voltage and lengthen the bunches.The Touschek lifetime increases are estimated for optimum and non-optimum voltage flattening.A tolerance of the operation is studied in case that there is a shift on detuning angle.The effect caused by reduction in harmonic voltage generated by lengthened bunch distribution is also estimated using iteration method.An increase in synchrotron frequency spread due to nonlinearity of the voltage giving to the bunch is found by using tracking simulation.This spread can help in damping coupled bunch instability through Landau damping.  相似文献   
955.
Growth hormone (GH) has been considered as a candidate gene for growth traits in fish. In this study, polymorphisms of the GH gene were evaluated for associations with growth traits in 282 Siniperca chuatsi individuals. Using directly sequencing, four single nucleotide polymorphisms (SNPs) were identified in GH gene, with two mutations in intron 4 (g.4940A>C, g.4948A>T), one mutation in exon 5 (g.5045T>C) and one in intron 5 (g.5234T>G). Notably, three of them were significantly associated with growth performance, particularly for g.4940A>C which was highly correlated with all the four growth traits. In conclusion, our results demonstrated that these SNPs in GH gene could influence growth performance of S.chuatsi and could be used for marker-assisted selection (MAS) in this species.  相似文献   
956.
The combustion behaviour and temperature of pulverised coal in a tuyere zone of the blast furnace could benefit to adjust the operation parameters, assure the stable state as well as maintaining high quality of hot metal of the blast furnace. However, there have been rare studies about this subject. In this paper, the digital imaging system based on the colour charge coupled device within gas-cooling and dustproof functions was established to capture the combustion radiation in the tuyere zone. For instance, images of tuyere zones of 2000 and 2500?m3 blast furnaces were detected through a peephole in front of the blowpipe by the application of digital imaging and image processing techniques, and the temperature distributions were also calculated. Some measurements were used to improve the accuracy of the results, and the combustion behaviour was also analysed.  相似文献   
957.
958.
根据某海下石棉矿采矿生产现状,分析目前矿山在地质、回采、运输及管理方面存在的问题,应用系统工程原理建立模型,制定方案并进行综合评价,利用统一规划法建立数量目标树和管理目标树,实现了生产管理的系统化,合理统筹人力、物力,极大的提高了管理水平,各项技术经济指标取得显著的效果.  相似文献   
959.
We synthesized various polymers with different functional groups of ─COO, ─SO3, and ≡N+─ to study the impact of the environmental temperature (25, 50, and 80 °C) on the dispersing capability by measuring the fluidity of fresh cement paste, total organic carbon, ζ potential, and isothermal calorimetry. The results show that no adsorption was observed for the cement pastes containing acrylic acid, 2-acrylamido-2-methyl propane sulfonic acid, and [3-(methacryloylamino)propyl] trimethyl ammonium chloride, probably because of the trace amount of adsorption, whereas the fluidity of the pastes was indeed improved by the addition of these chemicals. Generally, for the polymers containing various functional groups, the adsorption capability was in the order ─COO > ─SO3 > ≡N+─. The dispersing capability for the carboxylate superplasticizer was robust to the change in the temperature, whereas it was dramatically weakened by the increase in temperature for sulfonate superplasticizer, although the adsorption amount increased along with the temperature rise. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47494.  相似文献   
960.
By means of creep property measurement and microstructure observation, the influence of element Ru on the microstructure and creep behaviour of single crystal nickel-based superalloy is investigated. The results show that the plate-like μ phase is precipitated along {111} plane of the Ru-free alloy during thermal exposure at 1080°C and creep at 980°C. And the precipitation of μ phase in the alloy with 6(wt)%Mo and 6(wt)%W may be restrained by adding 2% Ru element. Compared to Ru-free alloy, the creep life of the 2% Ru single crystal alloy at 980°C200 MPa increases form 123 h to 333h. Compared to the 2% Ru alloy, the precipitated plate-like μ phase in the Ru-free alloy may promote the initiation and propagation of cracks along the γ matrix up to fracture, which is thought to be the main reason of the alloy having a lower creep resistances and shorter lifetime.  相似文献   
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