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101.
Sensilla comprising the sensory equipment of the antennal flagellum of eight species of Damalinia were studied using light and scanning electron microscopy. The sensillar complex consists of three pore organs and two sensilla coeloconica in both males and females. No relationship between their relative position in different genera and species has been found. The ‘pit organs' of the sensilla coeloconica have different shapes according to species. In the apex of the male flagellum, teeth are present in the species studied but the number and shapes are different. Adjacent to the teeth is a cluster of sensilla basiconica. At high magnification, no pores were found in the sensilla walls but their more or less blunt tips have small pores. The inner face of the male flagellum can be serrated or non-serrated.  相似文献   
102.
本文讨论抽样调查实践中有关设计和数据分析的若干问题.第一部分主要涉及设计问题.  相似文献   
103.
Frank E. Harris 《Pramana》2003,61(4):C779-C780
Guseinov, Mamedov, Kara and Orbay (Pramana - J. Phys. 56, 691 (2001)) propose methods for evaluating the molecular auxiliary functionsA n(p) andB n(pt) for the range 17 ≤n ≤ 60 and 25 ≤pt ≤ 60. However, their procedure forA n(p) is not new, and that forB n(pt) is less efficient for their target range than another well-known method. Their approach does have merit for smaller non-zero values ofpt. Two minor errors in table 1 of their paper are also identified.  相似文献   
104.
One of the main drawbacks of the augmented Lagrangian relaxation method is that the quadratic term introduced by the augmented Lagrangian is not separable. We compare empirically and theoretically two methods designed to cope with the nonseparability of the Lagrangian function: the auxiliary problem principle method and the block coordinated descent method. Also, we use the so-called unit commitment problem to test both methods. The objective of the unit commitment problem is to optimize the electricity production and distribution, considering a short-term planning horizon.  相似文献   
105.
A new method for the ultrafast generation of diffusion-weighted images is reported. The technique combines a quick echo split NMR imaging sequence with the principle of Stejskal and Tanner. It allows to determine the diffusion constant with nearly the same accuracy as the conventional spin-echo technique, requiring only a fraction of the time. The determined values for water doped with 1 g Cu(NO3)2 per liter of H2O and pure acetone were Dwater = (1.95 ± 0.02) × 10−9 m2/s and Dacetone = (4.05 ± 0.02) × 10−9 m2/s at 18.5°C. They are in good agreement both with literature and our own reference measurements using a diffusion-weighted spin-echo sequence. In addition, the temperature dependence of Dwater was measured in the range of 18.5–45.9°C and a good correspondence with reported data was found.  相似文献   
106.
线性规划在最优火力分配辅助决策中的应用   总被引:3,自引:0,他引:3  
采用层次分析法和线性规划法对坦克连冲击时目标价值和火力分配问题进行了分析.在理论分析的基础上,用C++Builder开发火力分配辅助决策软件,该软件以报告文件的形式显示目标价值结果,以报告文件或图形的方式显示火力分配结果.  相似文献   
107.
杨永青  伍贻康 《中国化学》2005,23(11):1519-1522
本文报道了利用四氯化钛媒介的不对称aldol缩合为关键步骤合成抗生素antimycin A的降解产物blastmycinone,并介绍了在研究过程中所观察到的一些意外现象。  相似文献   
108.
维实 《应用光学》1993,14(6):1-5
本文简要介绍了军用光电侦察装备在现代军事侦察中的作用和地位,几种主要军用光电侦察装备的发展趋势,提出了应该采取的技术对策和重点研究的课题。  相似文献   
109.
110.
Unless procedures for the economic evaluation of flexible manufacturing technology are revamped, much of U.S. industry could repeat the experience of American automobile and steel companies from the recent past. The dynamic character of flexible manufacturing technology in terms of associated developments in microelectronics, a trend toward equipment modularity, and the increasing diversity of relevant markets make flexible manufacturing especially vulnerable to the weaknesses of conventional procedures for the justification of capital expenditures. Building on the work of V. Smith, M.I. Kamien and N.L. Schwartz, this paper presents optimization models from which economically reasonable plans can be derived for the implementation of flexible manufacturing technology. Although the assumptions of these models are not focused on the situation of a specific plant, model implications and the overall perspectives here on the economic evaluation of flexible system options should provide general guidance for manufacturing planners.  相似文献   
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