平衡不稳

Based on the study of geological background conditions and the factors inducing the failure of dangerous rocks, this paper explains the distribution and morphological characteristics of dangerous rocks in Fengcheng town, provides the classification of the failure modes of the dangerous rocks in this area, and analyses the stabilities of six representative monomers of dangerous rocks qualitatively by stereographic projection method and quantitatively by limit equilibrium method.

文章在研究凤城危岩所处区域的地质背景条件及危岩失稳的诱发因素基础上，分析了凤城镇危岩体的分布规律及形态特征，根据破坏模式的不同对该区危岩进行了类型划分，采用赤平投影法与极限平衡法对该区6个代表性危岩单体的稳定状况进行定性与定量分析评价，经分析判断其均处于欠稳定或不稳定状态，需进行工程治理。

In the case when the rod is under constant twist and increasing tension force the straight equilibrium can be unstable and transfers to helical equilibrium.

在扭矩不变条件下增加拉力至极限值时，直杆平衡状态失稳转为螺旋杆状态。

It is worth mentioning that, a combination of the above-mentioned advantages of the valve is about to launch a new type of balance valve, it does not need to use instrumentation, debugging simple and quick, the workload of small, low prices, applicable to steady-state system, I believe it will be users.

值得一提的是，一种综合了上述阀门的优点的新型平衡阀即将面世，它不需要用仪表，调试简便快捷，工作量小，价格较低，适用于稳态系统，相信它会受到用户的欢迎。

When the system starts, the speed outer ring saturats non-functional, the current inner ring plays a major role to regulate the starting current to maintain the maximum so that the speed linear change, to reach a given value; when it operates steadily, the speed negative feedback from the outer ring plays a major role ,to let the speed changes with the given speed voltage , at the same time the current inner ring regulates the armature current of motor adjustment to balance the load current.

该系统起动时，转速外环饱和不起作用，电流内环起主要作用，调节起动电流保持最大值，使转速线性变化，迅速达到给定值；稳态运行时，转速负反馈外环起主要作用，使转速随转速给定电压的变化而变化，电流内环跟随转速外环调节电机的电枢电流以平衡负载电流。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐