难达到的

Inner of high temperature is very easy to dock a place to the steel tube coating creation destroys welding because the operation is complicated and Asbestus rope heat insulation effect. Change in the area metallographic organization fever of arousing is affected and the remaining strain arouse strain corroding a dehiscence to create inner steel tube bringing about the ring oxygen powder series falls short of success. Carrying out a certificate is not a preferred plan.

此种方法由于扩口时的精度不高，现场施工环境和条件所限，很难达到预期的效果，加之操作复杂、石棉绳绝热作用的不充分性等引起的焊接高温很容易对钢管对接处的内涂层产生破坏，同时还引起热影响区金相组织发生变化、产生残余应力而引起应力腐蚀开裂，造成环氧粉末系列的内防腐钢管功亏一篑，实践证明不是最佳方案。

As a result, a simple control method can not improve the dynamic performance of speed servo system. Integrated the advantages of self-adaptive control, fuzzy control and PID control, an intelligent dual module NC servo controller, called self-adaptive fuzzy PID controller is designed according to the modular design principle.

在光干涉弹流油膜测量系统中，速度伺服系统的控制参数和结构参数是影响速度伺服系统性能的主要因素，且具有时变性和不确定性，采用单一的控制策略很难达到提高速度伺服系统的动态性能的目的。

Bioflocculants are newly developed natural macromolecular organic substances produced by microorganisms, which have the ability to flocculate the suspensions and separate solid from the mixed.

中文摘要：生物絮凝剂是由微生物产生的一类生物大分子物质，具有一定的絮凝活性，能使液体中难沉降的固体悬浮颗粒凝聚，加速沉降以达到固液分离的目的。

The mankind has been destined to live in island universe isolating individually by oneself since born, thousands and hundreds years, people pursuing the real love show it is difficult to uniform two single bodies completely.

人类自出生后，便注定生活在自己个别隔离的岛宇宙内，千百年来人类对爱情的可歌可泣的追求，表明很难达到两个孤立的个体完全合而为一。

Has a remarkably wide range, though it is difficult to achieve (the high b makes the first string very taut such that it will break easily), and may not play well on an acoustic guitar (the low C is too low to resonate properly in a standard guitar's body). Luthier Todd Keehn claims to have been the first guitarist to adopt an all-fifths tuning, his being arranged G-D-a-e-b'-f#', and he has made an all fifths tuned guitar that can be seen at his website, http://tkinstruments.com/.

这个调弦的音域相当地宽，但是也很难达到要求（高音B使第一弦崩得非常紧，容易断）这个调弦在原声吉他上的效果也不理想（低音C太低在普通的箱琴上无法产生共鸣）据说Luthier Todd Keehn是第一个用这种调弦的吉他手，他还用 G-D-a-e-b'-f#调弦，他的全五调弦的琴可以在他的网站上看到 http：//tkinstruments.com/。

The analysis results showed that the strapdown approach will be faced to more error sources with sensor noise and motion disturbance. The simulation results verified this and indicated that the performance of the strapdown approach would not be as efficient as that of the direct approach.3. Analyzing the principle and error model of MEMS QRS gyro for the purpose of practical applications, the paper presented an autoregressive model for the gyro signal by means of time series theory.

应用牛顿力学原理分析了光电稳定跟踪机构的惯量耦合关系和动力学模型，推导了平台单轴伺服回路的控制方程，比较了直接稳定和捷联稳定方案在测量噪声和外部扰动共同作用下的性能特点，仿真结果表明，在同等噪声和扰动条件下，捷联稳定面临更多的误差源，因而最终的稳定精度较难达到直接稳定系统的水平。3。

Now, Flavonoids and ginkgolides were mainly extracted from the leaves of Ginkgo biloba., but the leaves often contain high content of corious and cereous, and the effective constituent is very different under the various conditions. In addition, the constituent of ginkgolides is very low in the leaves, and thus the quality of extraction is difficult to reach the international standards.

目前人们主要从银杏叶中提取银杏黄酮和萜内酯，但由于银杏黄酮和银杏内酯的含量很低，尤其银杏叶中最主要的有效成分银杏内酯B主要存在于根中，在银杏叶中含量极低(＜0.1％)，且是在生长状态的叶中含量最高，采叶影响树的生长；又因银杏叶中主要的有效成分受多种因素的影响又有很大差别，银杏叶革质化、蜡质化程度高，使得国内银杏叶提取物的质量很难达到国际标准。

Autologous MSC can be obtained easily,their source in human are plenty , own active proliferationand potential to difference into chondroblast.

自体骨髓基质干细胞来源丰富，取材容易，具有旺盛的增殖能力及向成软骨细胞分化的潜能，已成为软骨组织工程的首选种子细胞，但MSC诱导分化为成软骨细胞且应用于软骨组织工程的技术尚不十分完善，目前主要采用的技术为细胞团块离心管培养，其构建的软骨组织在力学性能上很难达到关节软骨的要求。

Inorganic Se could be transformed into organic Se after malt steeping, germinating and kilning, which not only satisfies human need but also keeps human being and animal from the overtaking of Se by malt.Malt was used as a carrier of Se, not only, for it's nutritious, edible and medicinal but also for it's useful in food industry, especially in brewing.

我们把麦芽作为富硒载体不仅因为麦芽营养价值高，而且兼有食用、药用、酿造用等多种用途，因而麦芽在食品工业中占有很重要的地位，特别是在酿造工业上，麦芽是酿制啤酒的主要原料。2001年我国啤酒产量达2200万吨，需麦芽300万吨，但由于国产啤麦制麦性能较差，麦芽的质量指标很难达到原轻工部部颁优级品的标准。

In the case of polyphonic music signals, the estimation of the parameters of sinusoids is a difficult task, since the periodic components are usually not stable. A sufficient time and frequency resolution is also difficult to achieve at the same time.

因为周期分量通常不稳定，在多重的语音信号中，估计正弦模型的参数是一项十分困难的任务，同时也很难达到较高的时间和频率分辨率。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。