THE FEEDBACK DELAY IN DIGITAL CONTROL

It is a fact that the feedback delay actually ariese in digital control systems.It is necessary to modify the structure of digital control systems and develop new control algorithms,which is done in this paper.A great number of digital computer simulation experiments have shown the obvious advantage of the new algorithms.     

Optimization of system reliability by adaptive randomly directed search

A new adaptive randomly directed search algorithm was developed for optimizing the reliability of a system employing redundancy. This algorithm can handle general nonlinear integer formulations. Its usefulness and advantages in solving reliability problems were demonstrated through three examples given in the literature.     

Effects of homogenous loading on silicon direct bonding

The effect of a homogenous loaded stress on the bonding quality of silicon wafer pairs was investigated by employing a Nano-Imprint System and a homogenous plane-stress applied over the entire surface area of pre-cleaned wafers. In addition, the effects of variations in the applied homogenous stress (1, 10, 100, 500 psi) on the interface energy of the bonded pairs were examined using a dynamic blade insertion (DBI) method. Infrared imaging was used to evaluate the quality of the bonded interface of each bonded pair immediately after the bonding process and after allowing the bonded pairs to rest at room temperature for 80 h after bonding. The results indicated that the homogenous loading with the Nano-Imprint System further improved the bonding condition of wafer pairs that had been pre-bonded using an anodic bonder. Furthermore, the bonded pairs exhibited almost identical interfacial energies of about 0.2 Jm⁻² when the homogenous stress was varied from 1 psi to 500 psi, which clearly indicates that the interfacial energy of bonded wafers is independent of the amount of stress applied by the homogenous loading process.     

Identification of multiple-input single-output Hammerstein models using Bezier curves and Bernstein polynomials

This paper considers the implementation of Bezier–Bernstein polynomials and the Levenberg–Marquart algorithm for identifying multiple-input single-output (MISO) Hammerstein models consisting of nonlinear static functions followed by a linear dynamical subsystem. The nonlinear static functions are approximated by the means of Bezier curves and Bernstein basis functions. The identification method is based on a hybrid scheme including the inverse de Casteljau algorithm, the least squares method, and the Levenberg–Marquart (LM) algorithm. Furthermore, results based on the proposed scheme are given which demonstrate substantial identification performance.     

On the mean and extreme distances between failures in Markovian binary sequences

This paper is concerned with the mean, minimum and maximum distances between two successive failures in a binary sequence consisting of Markov dependent elements. These random variables are potentially useful for the analysis of the frequency of critical events occurring in certain stochastic processes. Exact distributions of these random variables are derived via combinatorial techniques and illustrative numerical results are presented.     

诺氟沙星与环糊精的超分子体系

研究了诺氟沙星与β-环糊精(简称β-CD)及其两种衍生物羟丙基-β-环糊精(简称Hp-β-CD)、甲基-β-环糊精(简称Me-β-CD)形成的超分子体系.利用荧光光谱法测定了超分子体系的包结常数和包结比,及其热力学参数.诺氟沙星与3种环糊精均形成1∶1稳定的包合物,诺氟沙星与β-CD、Me-β-CD及Hp-β-CD作用...     

The design and use of a simple System Suitability Test Mix for generic reverse phase high performance liquid chromatography-mass spectrometry systems and the implications for automated system monitoring using global software tracking

The development of a seven-component test mixture designed for use with a generic gradient and a reversed-phase high performance liquid chromatography-mass spectrometry (RP-HPLC-MS) system is discussed. Unlike many test mixtures formulated in order to characterise column quality at neutral pH, the test mixture reported here was designed to permit an overall suitability assessment of the whole liquid chromatography-mass spectrometry (LCMS) system. The mixture is designed to test the chromatographic performance of the column as well as certain aspects of the performance of the individual instrumental components of the system. The System Suitability Test Mix can be used for low and high pH generic reverse phase LCMS analysis. Four phthalates are used: diethyl phthalate (DEP), diamyl phthalate (DAP), di-n-hexyl phthalate (DHP) and dioctyl phthalate (DOP). Three other probes are employed: 8-bromoguanosine (8-BG), amitryptyline (Ami), and 4-chlorocinnamic acid (4-CCA). We show that analysis of this test mixture can alert the user when any part of the system (instrument or column) contributes to loss of overall performance and may require remedial action and demonstrate that it can provide information that enables us to document data quality control.     

The Application of an Enzyme Electrode for Blood Glucose Determination in the Automated Flow System

Abstract

An enzyme electrode containing immobilized GOD was utilized in a continuous flow system for the automatical determination of glucose. The advantages of kinetic measurement of H₂ O ₂ are used. Characteristic parameters of device and results in routine are shown. Particular advantages are: low requirement on material (20 μl blood, < l μg GOD/measurement) and time (60 samples/h at 15 sec response time) as well as sufficient precision and accuracy (S % - serial: < 2 %).