查询词典 natural selection

The worst drought in Beijing continues in these years, since 2006, the corn production method shifted from irrigable cultivation to rained dry field cultivation, which brought the changefully items during the breeding period by taking advantage of natural precipitation, plus the unsuitable way of corn selection, these items will cause the reduction production of corn.

近年来北京地区持续干旱，自2006年起玉米生产开始由灌溉栽培转向雨养旱作生产，随之带来利用自然降水播种导致播种时期的不确定性，品种选择不当将导致严重减产，品质大幅下降。

The book covers both plants and animals, and deals with all relevant areas of research, including biogeography, field work, systematics, theory, and genetic and molecular studies, with special emphasis to topics,including sympatric speciation, reinforcement, the role of hybridization in speciation, the search for genes causing reproductive isolation, and mounting evidence for the role of natural and sexual selection in the origin of species.

该书内容覆盖植物和动物，并且涉及所有相关的研究领域，包括生物地理学，野外工作，系统分类学，理论，和遗传和分子研究，特别强调了包括同区域物种形成，增强，杂交在物种形成中的作用，寻找导致生殖隔离的基因，寻找自然和性别选择在物种起源中作用的证据。

The geology research of carbonate reservoirs in Ordovician of Tahe oilfield showed that many large dissolved vugs and fractures were developed. The spread of the reservoir take on a very heterogeneous state. And the typical fractured-vuggy reservoirs was formed. According to the combination of the various spaces, the formation was divided into vuggy formation, fractured-vuggy formation and fractured formation. The research showed that development of the vug is relevant to the its position on the structure, the fractures, the water surface and the weathering surface. Multi-phase charge and recharge of the oil in the reservoirs resulted in the complexity of the fluid distribution. So the"Bottle Model"was brought forward to explain the movement of the water-oil contact. The special storage space and the complex fluid distribution lead to the unstability of the production and the complexity of the water cut. In order to explain the characteristic of the fracture-vug unit was brought forward and the basic principle and method of the partition of the fracture-vug unit was formed. The classification and evaluation of the units were performed according the reserve and energy. Based on the research of geology characteristic and the fluid flow in the reservoir the comprehensive numerical simulation plan of the fractured-vuggy reservoirs were established. Through the selection of the simulation unit, fluid flow type and parameter equivalent the triple media reservoir simulation model was established. Considering the practical application the model was resolved by the DKR decomposition conjugate grads method. Based on the fine reservoir description of Dsitrict IV of the Tahe oilfield the various space type were classified and combined together. The geology model of Unit S48 was constructed. Two typical single well model was established according to the geology and the dynamic phenomena. Finally the single well model and the Unit S48 were simulated by the triple media reservoir simulator. Via the local grid refinement and coarsening in the simulation good matchs were gained. Based on the results of the simulation the reserve distribution, percent of reserve produced in various space and the natural energy were analyzed. The fluid was storaged in the fractures and vugs mostly and more than 90% the produced oil came from the systems. The energy belonged to the active one. The results of simulation accorded with the fact and showed the validity and practicability the research and the simulator.

塔河油田奥陶系碳酸盐岩油藏的地质研究表明，其储层中发育着很多大型的溶蚀洞、缝，储层的平面展布呈现出极度的非均质性，形成了典型的缝洞型碳酸盐岩油藏，根据各种孔隙介质在储层中的组合，将储层分为了溶洞型、裂缝-溶洞型和裂缝型三类；研究表明溶洞储层的发育和构造位置、裂缝的发育、潜水面和风化面的位置等因素有关；多期充注的油气成藏模式导致了流体复杂的赋存状态，由此提出了所谓的&瓶子模型&，解释生产过程中油水界面的变化；特殊的储集空间类型和流体分布特征导致油田在开发过程中表现出很大的不确定性和含水变化的复杂性，为了合理的解释油气田开发过程中的动态特征，提出了&缝洞单元&的概念，并制定了&缝洞单元&纵横向划分的基本原则和依据及划分方法，并对&缝洞单元&进行了分类和评价；基于地质特征和流体在其中流动规律的研究，提出了缝洞型碳酸盐岩油藏的数值模拟综合解决方案，通过模拟单元的选择、流动类型和参数的等效，建立了三重介质油藏三维三相数值模拟模型，采用不完全LU分解预处理共轭梯度法进行了求解；在塔河油田4区精细油藏描述的基础上，将各种类型的孔隙空间进行了归类组合，建立了S48单元的地质模型；通过对油井生产动态进行分析研究，建立了两类和油井地质、生产动态相对应的单井模型；最后应用三重介质油藏数值模拟软件对单井模型和S48单元进行了数值模拟，通过局部加密和粗化等技术模拟流体流动规律，取得了很好的拟合效果；结合数值模拟结果，分析了各种介质中的储量分布、储量产出的百分比以及地层的能量，认为塔河油田缝洞型油藏中流体绝大多数储集于缝洞系统之中，所产出流体90%以上也来自于缝洞系统，其底水能量属于较充足的类型；模拟结果和油田实际情况符合较好，说明了地质研究和油藏数值模拟研究的正确性。

This paper set up a new feature selection model based on natural language processing. And based on this model, analyses in terms of syntax , semantics and pragmatics .

本文建立了基于自然语言处理的文本特征提取模型，并从语法、语义和语用三个层面进行了详细地分析。

The shell resource utilization by these species in natural environment was studied and compared with result for laboratory shell selection experiment of the intertidal C. latens.

本论文之目的在研究此两种寄居蟹对贝壳资源的利用，另外利用潮间带的C。

Since 2000, the project I had/have been responsible for include:Health Effects of Fine/Ultrafine particles in ambient air of Beijing founded by Natural Science Foundation China and also cooperated with GSF, Germany; Energy Selection and Health Benefits in Beijing and China funded by IES program of USEPA, Study of Environmental Cost Model in China funded by USEPA, Risk Assessment for health Effects of Biological Indoor Air Pollutants and outdoor air pollution funded by China Ministry of Science and Technology; Health Effects of Fine Particles from the Dust Storms in China funded by NSFC and also cooperated with NIER, South Korea, etc.?

目前有在读的博士生2人、硕士生6人，MPH5人。主要研究方向为室内外空气污染对人群健康影响的定量评价及方法、环境污染健康风险评价及方法学。目前主持承担的科研项目有：国家自然科学基金重点项目&大气细颗粒和超细颗粒的环境行为。界面过程和健康效应&，国家&十一五&科技支撑计划项目&建筑室内生物污染控制与改善关键技术研究&和&环境污染的健康风险评估与管理技术研究&，欧盟课题&健康与环境网络建设&、韩国环科院合作项目《亚洲沙尘污染对儿童健康影响的比较风险研究》等

Anhui Province will select a number of scientists and qualified technicians to attend workshops to be developed by scientists from College of Agriculture and Natural Resources to study variety selection and improvement, production, harvesting techniques, post-harvest processing , cold-storage, and other areas as deemed appropriate.

安徽省可选择一些科学技术人员参加由马里兰州大学农业和自然资源学院举办的培训班，或到农场、农业企业进行和自然资源学院将为培训提供合适的服务。

Is a professional diamond tools production plant, product selection of high quality diamond and cubic boron nitride refined form, the variety many, the specification entire, the product has assorted diamond file, large sheet filing, grinding, grinding head, grinding wheel, saw blade, grinding wheel, carbide rotary burrs, grinding, hole drilling, Wire Saw, File, natural diamond grinding wheel cutter, metal pens and diamond polishing paste, oilstone, and the system for various types of non-standard shaped diamond Tools product line.

江苏锋菱超硬工具有限公司是一个生产金刚石工具的专业化工厂，产品选用优质金刚石和立方氮化硼精制而成，品种多，规格全，产品有金刚石什锦锉、大板锉、磨针、磨头、砂轮、锯片、磨轮、硬质合金旋转锉、磨盘、孔钻、绳锯、锉刀、天然金刚石砂轮刀、金属笔及金刚石研磨膏、油石等，并承制各类非标异型金刚石工具系列产品。

Teachers in blurbs used to close the text, close to the life, natural, elegant, and the proper selection of effective method, can enter "artistic" position, make the teaching in the first "first love" in tune.

教师在导语的运用中，要贴近课文，贴近生活，自然恰当，新颖别致，并选择有效的方法，オ可以进入&艺术性&的境地，使教学在第一时间就&未成曲调先有情&。

Teachers in blurbs used to close the text, close to the life, natural, elegant, and the proper selection of effective method, can enter "artistic" position, make the teaching in the first "first love" in tune.

教师在导语的运用中，要贴近课文，贴近生活，自然恰当，新颖别致，并选择有效的方法，才可以进入&艺术性&的境地，使教学在第一时间就&未成曲调先有情&。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。