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This article presents and compares key characteristics of population of illicit opioid users outside treatment in five cities across Canada (OPICAN cohort).


rubrum, and that downstream riffles showed characteristics of population sinks.


This problem is explored with a case study of Milwaukee, Wisconsin, examining the incidence of environmentally suspect, taxdelinquent properties by census tracts and associated socioeconomic characteristics of population within these tracts.


Combined analysis of the spatial characteristics of population migration structure demonstrated that the Pacific coast of Eurasia has played a special role in population genetic processes.


The spatial characteristics of population distribution and growth, migration, fertility and mortality from a global perspective.

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 The present paper proposes some aspects and procedures for establishing the longterm predictive equation of locust population fluctuations. Three kinds of predictive population models are introduced and discussed with respect to their practical value. Aseries of locust population data of 50 years, 19131962, taken from HungTze Lake, a typical locust region, has been used to analyse the regularity of locust population dynamics, from which the effective factors have been selected to build up the predictivemodels.... The present paper proposes some aspects and procedures for establishing the longterm predictive equation of locust population fluctuations. Three kinds of predictive population models are introduced and discussed with respect to their practical value. Aseries of locust population data of 50 years, 19131962, taken from HungTze Lake, a typical locust region, has been used to analyse the regularity of locust population dynamics, from which the effective factors have been selected to build up the predictivemodels. 1. Analysis of Outbreak Regularity 1) The running equation, E=(k2npq)/(npq(13pq)~(1/2)) is employed to test the independence on outbreaks of one another. It is found that some connections are present between two neighbouring outbreaks. This means that each outbreak would be consideredas a continuous part of the population fluctuation sequence which is influenced by theresultant effect of both locust bionomics and environmental factors. 2) Results obtained about the influence of climatic factors, by the analyticalmethods of contingence table and conditional probability, show that a dry climatic year ismore suitable to the locust population growth than wet years, and a dry summer is particularly favorable as compared with spring. Such climatic condition may be expressed bythe climatic index shown as follows: Precipitation saturation deficit<3 andcharacteristics of population fluctuation sequence: It is indicated that if thevalue of population abundance deviating from the mean level (y = 4.141) is plusor minus 2, the fluctuation tendency will reverse, for example, when x_ix_(i+1)>x_(i+2) then x_(i+3)>x_(i+2), generally x_(i+3)<4.1. 2. By the methods of random sequence and periodical equations based on environmental factors and population bionomics: the followng model is used y_t=f(t)+ξ(t)+g(t)(y(t)…predicted value of population abundance, f(t)…tendency factor, ξ(t)…random factor, g(t)…periodical factor) The estimation of these three factors dissolved are f~*(t)=4.4750.0084t+0.38 sin (π/(12)t) ξ~*(t)=0.1186ξ(t1)0.1452ξ(t2) g~*(t)=g_7(t)+g_8(t)+…+g_(12)(t) 3. By stepwise multiple regression method: Equations are established based onnumerous variates, many of which have been sifted under given confidence levels (F=1.5,2.5) before they are taken in the predictive models. 1) Linear regression equa  本文以洪泽湖蝗区为例,分析了东亚飞蝗中长期数量预测方程的建立基础,提出三种预测方法:(一)根据种群动态型趋势进行外推估值,(二)应用随机序列及周期方程的预测法,(三)多因素过滤回归预测法,此三种方法虽各有其独立的预测模式,但在应用时应将其视为总预测式中的三个相互补充的部分。  Up to now, the fatigue loads are usually statistically treated in accordance with onedimensional random variable at home and abroad. In this paper, the twodimensional random variables are adopted in statistical treatment of fatigue loads in order to characterize a cyclic load perfectly and to simulate the loadbearing condition of a component truly. Herein we have taken the actually measured data of a flying subject of fighters as an example. The characteristics of population were inferred from a sample,... Up to now, the fatigue loads are usually statistically treated in accordance with onedimensional random variable at home and abroad. In this paper, the twodimensional random variables are adopted in statistical treatment of fatigue loads in order to characterize a cyclic load perfectly and to simulate the loadbearing condition of a component truly. Herein we have taken the actually measured data of a flying subject of fighters as an example. The characteristics of population were inferred from a sample, then the typical program load spectra were compiled according to this population distribution. They may be used for full scale fatigue test or evaluation of fatigue life.To consider the effect of spectrum types, we have performed the comparative tests in groups between a random load spectrum and four program block spectra on MTS fatigue testing machine. Five or six specimens were used in each group. The results show that there is no significant difference in test lives between the shortperiod program block spectra of 晇ariable amplitude or variable mean and the actually measured random spectrum.  目前,国内外对疲劳载荷常按一维随机变量进行统计处理。为了更好地反映循环载荷固有特征,更真实地模拟构件承载情况,本文采用二维随机变量进行统计处理。 本文以歼击机的某一飞行科目的实测数据为例,由子样推断其所属母体的性质,再根据母体分布编制出具有代表性的程序载荷谱,可用于全尺寸疲劳试验或寿命估算。 为了考虑谱型的影响,在MTS电液伺服疲劳试验机上进行了随机谱和四种程序块谱的成组对比试验,每组使用了5～6个试样。实验结果表明:短周期的变幅值或变均值程序块谱与实测的随机谱给出的试验寿命无显著差异。  This paper reports the results of an epidemiological investigation on the congenital anomalies for 14,2 14 neonatal infants in Lanzhou city and Dingxi district,Gansu Province.The method of clinical examination was used for diagnosis of congenital abnormalities.The incidence rate of congenital anomalies was 6.4%.The types of the anomalies were defects of nervous system(anencephalus,hydrocepha lus,spina bifida),limbs,face,circulatory and digestive system.The relationship between the incidence of anomalies and... This paper reports the results of an epidemiological investigation on the congenital anomalies for 14,2 14 neonatal infants in Lanzhou city and Dingxi district,Gansu Province.The method of clinical examination was used for diagnosis of congenital abnormalities.The incidence rate of congenital anomalies was 6.4%.The types of the anomalies were defects of nervous system(anencephalus,hydrocepha lus,spina bifida),limbs,face,circulatory and digestive system.The relationship between the incidence of anomalies and characteristic of population was discussed.  本文报告了兰州市和定西地区1984—1985年住院出生的14.214名新生儿先天畸形的发生率。先天畸形的诊断主要靠临床物理检查的方法。调查结果,新生儿先天畸形发生率为6.40‰。定西地区(11.59‰)高于兰州市(5.69‰)。农民(12.39‰)高于工人(4.60‰)、干部(4.02‰)和科教医护人员(4.91‰)。先天畸形的主要类型是神经系统畸形(无脑儿、脑积水、脊椎裂),其次是四肢颜面畸形。文中讨论了先天畸形与母亲年龄、职业等的关系。   << 更多相关文摘 
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