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61.
62.
The ripple-free deadbeat control problem for SISO plants subjected to arbitrary reference signals is considered. The trade-off between the settling time and the integral square error between the system output and reference signal is investigated. Given a specific order of the controller, it is shown how to design an optimal ripple-free deadbeat controller. An illustrative example is presented to show the feasibility of the proposed algorithm.  相似文献   
63.
This paper considers a pole assignment problem to cluster all poles of a closed-loop system into some specified regions by introducing the complex state for systems having an isotropic property and by using the Riccati equation. The algebraic relations for the distribution of the eigenvalues of a complex matrix are used in order to cluster the poles into specified regions, which guarantees the relative stability margin, e.g. uniform damping or uniform damping ratio. The proposed scheme is essentially a combination of the pole assignment approach and linear quadratic design, taking the advantages of both. A block modal control method—an extension of recursive pole assignment—is also developed for the vibration control of rotating systems by clustering the forward and backward modes in order. Vibration control simulations with an isotropic rotor—bearing system, a magnetic bearing system and a rotating circular disc are treated in order to demonstrate the advantages of the proposed method.  相似文献   
64.
基于Lyapnuov泛函方法,研究了满足匹配条件的不确定性时滞系统的鲁棒稳定性及具有稳定度β〉0鲁棒稳定性,给出了已有结果不能推出的新判据。这些新判据对已有结果难以使用的情况下也可有是有效的,或有时减少了已有结果的保守性。  相似文献   
65.
Background : In order to find the most useful computerized auditing system for the needs of the QE II Hospital surgical department three surgical auditing software programs were assessed. Methods : The Otago University Surgical Auditing Program, the Australian Surgical Auditing Program, and RACS-Audit were trialled for a period of 1 month each. The software programs were evaluated to find the time requirements for data entry, the level of surgical knowledge needed for effective audit information entry, and the perceived usefulness of the generated reports. Results : It was found that the Otago University program best suited the needs of the department. This system was designed for use in a hospital environment with multiple users. The method of data collection was simple and rapid. Entry of data into the program was logical, well structured and able to be performed by both junior medical staff and clerical staff. Reports generated by this system included information in an appropriate format for the departments' morbidity and mortality meetings. Conclusion : Personal computers are an ideal tool for the undertaking of surgical audit. Software programs are designed for different uses and should be critically assessed to ensure that the method of data entry, the time involved, and the reports generated enable an efficient and effective audit to be carried out.  相似文献   
66.
67.
经过对多层界面液膜的实验探索,获得了四相物系双层界面液膜和五相物系三层界面液膜等一系列多层界面液膜。并且提出了多层界面液膜自动形成的一般式,由此,展示了多层界面液膜的广阔领域。其中每一种多层界面液膜在应用上都将有其广泛的发展前景。  相似文献   
68.
We have compared the performance of the Baxter disposable with the Graseby electronic patient-controlled analgesia system in 30 patients following major gynaecological surgery. Patients were allocated randomly to receive analgesia via the Baxter or Graseby device for postoperative pain relief. There were no significant differences between the two groups with regard to postoperative pain relief or sedation as measured by visual analogue scale. Requirements for antiemetic drugs and patient acceptability were similar. Mean (SEM) morphine demanded over 30 h was 35.7 (6.6) in the Graseby group and 35.1 (8.5) in the Baxter group.  相似文献   
69.
用K.S熵(一种信息熵)判别林业系统中生态和经济的协调关系,并提出了控制和改进现有林业系统的有效途径。  相似文献   
70.
病原生物学多媒体网络互动教学实验室的建设与展望   总被引:5,自引:0,他引:5  
介绍了病原生物学多媒体网络互动教学实验室的建设和应具备的功能 ,论述了多媒体互动网络的建成对病原生物学实验教学环境和实验教学效果的积极促进作用 ,并对实验室以后的发展方向进行了展望  相似文献   
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