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181.
The maximum consumption of the larvae of the pest and vector mosquitoCulex quinquefasciatus by the predatory mosquitoCulex (Lutzia) raptor was studied at various instars of both the predator and the prey. The prey preferences of the predator when given lavae of different instars were also investigated. The IVth instar of the predator consumed the maximum number of Ist instar and the maximum biomass of IVth instar larvae of the prey. Instars I and II of the predator preferred the Ist of the prey; instars III and IV of the predator preferred instars II and III of the prey respectively.The predator consumed an average of 157.1 larvae during its whole larval period, when each instar of the predator was given its preferred instar of the prey. 相似文献
182.
用子波变换分析方法实时监测视觉诱发电位的潜伏期 总被引:1,自引:0,他引:1
诱发电位的实时监测在临床中有重要意义。本文提出利用多分辨率子波分析技术来实时监测视觉诱发电位的潜伏期。为克服随机噪声的影响,我们引入相邻响应的相关系数来修正所检测得的潜伏期的偏移,并应用前一次响应的波峰位置来决定当前的搜寻范围。实验表明,本方法能实时监测视觉诱发电位的潜伏期。 相似文献
183.
针对二进制第Ⅱ类混合自动请求重传差错控制系统流量偏低的问题,提出了基于Reed-Solomon(RS)码的多进制混合自动请求重传方案.该方案将信息经RS码编码后,采用多进制调制,信息部分与校验部分分开传输,码的可逆性使得仅由无误的校验部分便可恢复出信息,利于提高流量.数值结果表明,该方案在Rician衰落信道下的流量比传统的二进制方案有了明显提高,同时可靠性依然保持与二进制方案相同的水平. 相似文献
184.
The pericratonic sedimentary Jaisalmer Basin, west of the Aravalli Ranges, on the westerly dipping eastern flank of the Indus Shelf, is a principal structural element of Rajasthan. Jurassic sediments in the SE comprise non-marine sandstones and conglomerates to nearshore, brackish to marine sands, silts, clays and carbonates, grouped lithostratigraphically into the Lathi, Jaisalmer, Baisakhi, and Bhadasar formations. The Late Bajocian to Oxfordian Jaisalmer Formation is divided, in ascending order, into the Hamira, Joyan, Fort, Badabag, Kuldhar, and Jajiya members. Fossil records providing a Bajocian to Bathonian age for the lower and middle parts of the formation include: a Late Bajocian coral Isastraea bernardiana (d’Orbigny) in the uppermost Joyan Member; Bathonian ammonite Clydoniceras in the basal part of the Badabag Member; Bathonian foraminiferal/bivalve assemblages in the Fort Member. The topmost bed of the Joyan Member represents the peak of first marine transgression of the Jaisalmer Basin, probably contemporaneous with the Late Bajocian one in the neighbouring Kachchh Basin. Based on faunal studies Bajocian to Bathonian sediments of the Jaisalmer Basin can be broadly correlated with those of the Kachchh Basin. The Fort and Badabag members represent the following depositional environments, in chronological order: (a) brackish to shallow fully marine; (b) fully marine with rapidly fluctuating water energy and sedimentation rates; (c) near-shore to lower shoreface with fluctuating energy conditions, salinity and sedimentation rates; (d) near-shore to shoreface channels and storm-dominated marine above fair-weather wave-base; (e) lagoon with fluctuating low to moderate energy, salinity and sedimentation rates; (f) stormdominated shelf to lower shoreface. 相似文献
185.
论信息市场环境下的图书馆营销观 总被引:3,自引:1,他引:3
分析了信息市场的发展对图书馆信息资源建设、信息技术的开发以及信息传播方式和获取手段所产生的影响,探讨了面对激烈的市场竞争图书馆引入营销观念的必要性,并对具体的营销策略做了详尽的阐述。 相似文献
186.
NPP distribution related to the terrains along the North-South Transect of Eastern China 总被引:2,自引:0,他引:2
LI Yan LIAO Shendong CHI Guobin & LIAO Qifang . Spatial Information Research Center South China Normal University Guangzhou China . Guangdong Key Laboratory of RS GIS Applications Guangzhou China 《科学通报(英文版)》2004,49(6):617-624
Vegetation net primary productivity (NPP) is defined as the accumulative amount of organic matters per unit area and time, which is calculated from the difference between accumulative photosynthesis and accumulative autotrophic respiration by green plants. Since the NPP reflects the physiological and ecological characteristics of the plants and the interactive results of the environmental factors, it is an important index to evaluate a structure of ecological system, functional features and … 相似文献
187.
Nomenclature ki integral action coefficient[s-1]kp speed proportional gain[s-1]kv position proportional gain[s-1]kf feed forward factor of the speed loop[%]M axis mass[kg]V speed[m/s]F driving effort[N]Rc radius of curvature[m]d distance to the apex[m]o lateral offset[m]εcontouring error[m]ωm lowest mechanical resonant frequency[s-1]ζdamping coefficient[-]r inertia ratio[-]μmembership function[-]αcorner angle[rad]x,y horizontal and vertical coordinates[m]?angle to the normal line[rad]1.I… 相似文献
188.
Ibrahim M.AL-HARKAN 《系统科学与系统工程学报(英文版)》2005,14(2):187-206
1.Introduction Production sequencing and scheduling is one of the most important activities in production planning and control.Sequencing is defined as the order in which the jobs are processed through the machines.The allocation of machines over time to process a collection of jobs is defined as Scheduling.Several methods have been developed to solve the scheduling problem which can be classified as follows:1)efficient optimal methods,2)implicit and explicit,or complete enumerative methods,a… 相似文献
189.
GanShi-xin 《武汉大学学报:自然科学英文版》2004,9(1):13-17
This paper investigates some conditions which imply the strong laws of large numbers for Banach space valued random variable sequences. Some generalizations of the Marcinkiewicz- Zygmund theorem and the HoffmannJφrgensen and Pisier theorem are obtained. 相似文献
190.
ZhangNing LiuHai-lin YuZhu-xing XiongRui ShiJing 《武汉大学学报:自然科学英文版》2004,9(1):55-58
The characteristics of electronic transport properties: behaviors of magnetization curve and magnetic relaxation of a typical normal superconductor 2H-NbSe2 are investigated. The results show that Tc and △Tc of the samples are 7. 2,0. 18 K, indicating that superconducting energy gap at zero temperature is 1. 1 meV. No fish tail shape is found in the magnetization curves at several temperatures. The relationship between remnant magnetic moment and time reveals that the magnetic flux creep of the sample agrees with the Kim-Anderson thermal activation model with the relaxation rate S=0.000 36 at T=6 K. 相似文献