查询词典 ditch between fields

Methods of measuring the input components, their prices and output elements are given. We put forward some new methods in measuring components, including composite depreciation rate, equality working hours, and proxy of input resources. Using the mature methods of efficiency measurement and decomposition available, we make a detailed investigation into 4 listing companies of oil industry with a span of 12 periods. Basic conclusions we draw include: labor inputs affects oil field output mostly in China; China oil fields operates in a low technical efficiency level average of 0.61; Increasing difficulties with expanding output has the greatest influence on cost; Cost efficiency of China oil fields averages at 1.47; Total factor productivity of China oil fields averages at 10%, accounting for 79% of the total output growth rate of 12.6%; Frontier technology progress contributes the most to TFP of China oil fields with 17 percentage points.

本文沿用了已有文献中关于效率计量与分解的成熟方法，对我国三家油田上市公司与一家上市石油公司12个时期的技术效率与成本效率进行了详细的计量、分解与分析，得到的基本结论有：劳动力投入是影响我国油田上市公司产出的最重要的影响因素；油田的平均技术效率仅为0.61；产出项是影响成本的显著因素，这说明随着产出增加而出现的开采难度增加是导致开采成本增加的重要因素；油田的平均成本效率为1.47；全要素生产率的增长平均在10％左右，占到了产出平均增长率12.6％的79％，表明我国油田的生产率的提高主要是依靠全要素生产率的提高而实现的，只有21％左右的产出增长是依靠要素投入而实现的；前沿技术进步是油田全要素生产率增长的主要源泉，在2001～2004年期间，前沿技术进步对油田生产率的贡献高达17个百分点。

Recently, Professor Liu Wen and his associates study the strong law of large numbers for Markov chain fields on trees. But for the nonhomogeneous Markov chain fields ,they only study the even-odd Markov chain and non-symmetric Markov chain. However, this article goes in the normal nonhono-geneous Markov chain fields and gets a class of limit theorems for the functions of two variables of finite nonhomogeneous Markov chain fields. Some limit theorems on the frequences of states and ordered state couples are obtained by several corollaries.

最近刘文教授及其合作者对树上的马氏链场的极限定理作了研究，对于非齐次马氏链场，仅对其中的奇偶马氏链场和非对称马氏链场作了研究，本文讨论了一般的非齐次马氏链场的极限性质，得到了关于Caylay树上有限非齐次马氏链场二元泛函的一类极限定理，作为推论得到了关于状态与状态序偶出现频率的极限定理。

The wind fields andtemperature fields data provided by "D files" from 14 surface observationstations around Beijing area are used to produce the mean wind fields and the meantemperature fields over Beijing area in summer and winter. Such results are gotten:(1)Due to the unique topography the wind of Beijing area during the day time is southernanabatic wind and in the night is northern katabatic wind in summer.

Keywords：wind field； temperature field； urban heat island； urban boundarylayer； Beijing area 北京区域夏冬季风场、温度场的观测研究胡小明刘树华梁福明王建华刘和平王迎春李炬摘要：用北京及市郊地区共14个地面气象观测站的全月数据顺序文件&D文件&提供的风场及温度资料，采用逐时月均匀的方法对北京及周边地区的冬夏两季的风场，温度场特征进行了研究。

Results show that the insect community structure in the Bt fields differed sharply from that in the CV fields. The populations of the Lepidopterous pests, such as cotton bollworm, corn borer, diamond bollworm and cotton leaf caterpillar, decreased significantly in the BT fields, while the populations of non-target pests with piercing-sucking mouthparts, such as leaf bugs, cotton spider mites, cotton aphids and whiteflies, increased obviously. Much more predators, such as spiders and ladybirds, and much less parasitiods of Helicoverpa armigera were observed in the BT fields.

结果表明，与常规棉田相比，Bt棉田棉铃虫、玉米螟、金刚钻、棉小造桥虫等鳞翅目害虫种群数量显著降低，而盲蝽象、红蜘蛛、棉蚜、烟粉虱等非靶标刺吸式害虫种群数量显著增加；蜘蛛、瓢虫等捕食性天敌种群数量显著增加，而棉铃虫的寄生性天敌种群数量则显著下降。

Some fields are infested with wild oats and rye grass (Lolium spp.). Twenty-eight per cent of fields in the 1984 survey were moderately or severely infested with Phalaris minor and these fields yielded 1.4 t/ha compared to 1.9 t/ha for fields without weeds.

一些田块受野燕麦和黑麦草的侵害。1984年的调查表明28%的大田中度或严重受到小粒鹃草的侵害，这些田产量为1.4吨/公顷，而无草害田块产量是1.9吨/公顷。

Some fields are infested with wild oats and rye grass (Lolium spp.). Twenty-eight per cent of fields in the 1984 survey were moderately or severely infested with Phalaris minor and these fields yielded 1.4 t/ha compared to 1.9 t/ha for fields without weeds.

一些田块受野燕麦和黑麦草的侵害。1984年的调查表明28%的大田中度或严重受到小粒虉草的侵害，这些田产量为1.4吨/公顷，而无草害田块产量是1.9吨/公顷。

Transmissions at 0.75 and 1.65 μm can also be used to retrieve τ and re. 2. Study the impact of cloud inhomogeneity on the satellite retrieval simultaneously. Two 3D cloud fields, cumulus and stratocumulus fields are used in our study. The two cloud fields are generated with LES model and are adopted by the I3RC phase II. The BRDF at the wavelengths of 0.65 and 2.13 μm are calculated with SHDOM, and then the cloud optical thickness and effective particle radius are simultaneously retrieved using the MODIS algorithm. We studied the impact of cloud inhomogeneity on the satellite retrieval at high and medium resolutions. Some conclusions have been made, such as the BRDF abnormal phenomenon, the reverse relationship between τ and re, the clustering effect of over and under estimation in the retrieval of τ and re .

我们选用为I3RC所采用的由LES模式给出的具有明确物理属性的两个高分辨率三维云场－积云场与层积云场，利用SHDOM三维辐射传输模式来模拟卫星观测的辐射值，并采用MODIS算法进行反演，同时研究了在高分辨云场及中低分辨率云场下，云的非均匀性对反演云光学厚度及有效粒子半径的影响，并得到了云的非均匀性会造成的双向反射率异常，反演结果中光学厚度与有效粒子半径的负相关关系，高估或低估现象是成&簇&出现的等结论。

In the works mentioned above, we take some coupled effects into account, including the coupling between the FGM structures and elastic media or compressible fluid, the coupling between mechanical and thermal fields and the coupling between mechanical and electric fields.

在上述工作中，本文考虑了多个耦合因素，包括结构与弹性介质的耦合、圆柱壳与流体的耦合；力场与温度场的耦合、力场与电场的耦合。

The gravitational fields required to make such a closed time-like curve would have to be very strong,"on the order of what you might find close to a black hole," Ori told LiveScience."We don't have any way of creating such strong gravitational fields today, and we certainly have no way of manipulating any such gravitational fields."

要制造出这样一条封闭时间曲线的引力场非得要非常强，"大约和你在一个黑洞附近找到的那么大"Ori告诉LiveScience"我们现在没有任何办法来制造这么强大的引力场，而且，可以肯定地说，我们无法来控制任何一个这样的引力场"

ABSTRACTIn this paper, the characteristics of velocity fields and concentration fields of jets at different velocity ratios in counterflow and coflow ambient are studied in detail. The preliminary results of velocity fields of jet in reciprocating ambient are also acquired.

本文对反向流动、同向流动环境中不同流速比下射流的流速场特性和浓度场特性进行了研究，并对往复流动环境中射流的流速场特性进行了初步探讨。

According to our present broadcasting situation,the thesis proposes using new technology to update and reform the present HFC. It also suggests broadcasting using self-advantage and arranging EPON in order to win the supermarket.

论文从我国广电的现状出发，结合实际，积极倡导采用新技术更新、改造我国现有的HFC网络；倡导广电现阶段利用自身优势，部署EPON网络来赢取市场。

A new general kinetic equation was derived in which the effect of the removal of condensation water was taken into account completely, and was applied to the polyesterification kinetic study of AA/HPHP and AA/NPG. It was found that the reaction order of self-catalyzed polyesterification was not constant. For these polyesterifications, the reaction order was 2.5 at a low temperature, while 3.0 at a high temperature.

考虑缩合水的排除对反应体系的影响，用体积浓度单位推导出一个新的聚酯反应总包动力学方程，并应用到AA/HPHP和AA/NPG两个聚酯化反应的动力学研究中，研究发现，自催化聚酯反应的反应级数并不是固定值，对于AA/HPHP和AA/NPG两个聚酯化反应而言，低温时反应级数为2.5，高温时反应级数为3.0。