难以控制

To RPC, the fluidity was usually a key index, because it directly reflected the work-ability. The effect factors were complex, however, the quantity relation between the RPC fluidity and its effect factors could not be expressed with a uniform numeric formula. There was no effective method for this problem at present. In accordance, a numeric method which used for controlling the RPC fluidity was advanced. The neural network model based on genetic algorithm was introduced for a aptitude method consequently.

流动度是RPC配制的一个关键指标，它直接反映了其工作性的优劣，但其影响因素复杂，难以用统一的数值关系直接描述RPC流动度与其影响因素的量化关系，目前还没有合适的计算方法，为此，提出控制RPC流动度的数值方法，即引入遗传神经网络对RPC的流动度进行预测控制。

Greenhouse environment is a inertia , nonlinear, complex system with many variable. It's very hard to establish mathematic model and control with traditional control method.

温室环境是一个多变量的非线性复杂系统，难以建立精确的数学模型及用传统控制方法实现控制。

So the steady output power is hard to be gotten without the perfect control circuit and control method.

若没有完善的控制电路和控制方法要获得比较稳定的功率输出是难以达到的。

The results show that the system can keep certain smoothness with short delay, but the control precision can decline with the accretion of time delay, long random delay will not only reduce system expeditiousness, but also the smoothness and control precision at the same time. If the random delay is long enough, it can destroy the stability of networked control systems.

研究结果表明：系统在较小的延时下仍能保持一定的稳定，随着延时的增大，系统的控制精度有所降低；而较大的随机延时不但降低系统的总体快速性，同时，使系统的稳定性和控制精度明显降低，而当随机延时大到一定程度时，系统的稳定性难以保证。

Traditional authentication and access control technologies and means have been difficult to resolve heterogeneous collaborative environment Application System security issues, the fundamental reason is that identity can be forged, the environment and the dynamic changes of discrete control.

传统的身份认证及访问控制技术和手段已难以解决异构协同环境中应用系统的安全问题，根本原因在于身份的可伪造性、环境的动态变化以及控制的离散性。

In the fifth part, the H〓 control problem for Lur'e systems with multiple nonlinearities is discussed. The existence is reduced to solvability of multiple linear matrix inequalities. And the design method is simple and feasible via iterative optimal algorithm based on the interior-point method of LMI.

第五部分：研究了具有多个非线性环节的Lur'e系统的H〓控制问题，给出了基于双线性代数矩阵不等式的可解条件，此结果可覆盖关于线性系统相应问题的结论，同时又避免了目前在非线性系统H〓控制的研究中出现的偏微分矩阵不等式难以求解的问题。

Adjusting between welfare and punishment, tend towards middle of the road is the rule of juvenile justice policy development. Welfare is a kind of periphrastic juvenile control policy, the pretext to constructing juvenile justice system, and the groundwork that cannot been threw away during the development of juvenile justice.

本文通过对美国少年司法起源与变迁史的考察发现，无论是多么伪善或者直白，少年司法起源与变迁背后的推动力均主要源自成人社会控制少年的需要；而少年司法政策的演变规律则呈现出在福利与惩罚之间调整其立场，在总体上走向折中主义的趋势；作为一种"隐蔽而迂回"的少年控制策略，福利是建构少年司法的旗帜，也是少年司法变迁中难以背弃的根基。19世纪以前的美国，大体处于"前少年司法时代"。

How to measure exactly the coal mass of pulverizer in fossil power plant? It is one of primary causes that the efficiency of milling control is low and the automation is difficult to running. In this paper a method of solving uncertainty problem-evidential theory was studied principally from the view of the multiple sensor information fusion.

火电厂中钢球磨煤机筒内存煤量的测量问题一直是制粉控制效率低和自动控制难以投入运行的主要原因之一，本文从多传感器信息融合的角度出发，重点研究了一种解决不确定性问题的有力方法——证据理论方法。

However, there are some problems existing in the finance control of parent companies and subsidiary companies, such as the difficulty of mastering the extent of power centralization, the inaccurateness of the finance information and so on.

然而，对于现代母子公司财务控制来说，还存在集权与分权程度难以掌握，监管不力以及财务信息不准确等问题，这使得整个集团公司难以有效的协调运营，无法充分显现其规模优势。

The process of industrial production is sometimes nonlinear anduncertain and is difficult to establish accurate mathematic module, sousing routine PID controller is hard to achieve perfect controlling effect.

工业生产过程往往具有非线性、不确定性，难以建立精确的数学模型，应用常规的PID控制器难以达到理想的控制效果。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。