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21.
Analog Integrated Circuits and Signal Processing - A general topology for realizing nth order voltage-mode universal filter responses with multiple-input and single-output using only plus type...  相似文献   
22.
The paper presents simplified polynomial equations for determining the double‐K fracture parameters of concrete for 3‐point bending beams with variable strengths and material properties of concrete. The derived equations avoid complexities involved in computations of fracture parameters using existing analytical methods. The input data required for systematic computation in the study for deriving the nondimensional fracture parameters are obtained using a fictitious crack model. It is inferred that for a relative size of initial crack length, critical load and corresponding crack opening displacement maintain a linear relationship in their nondimensional forms. The value of critical mouth opening displacement can also be determined for known value of peak load using the derived nondimensional equation, thus avoiding the measurement of the crack mouth opening displacement in the experiment. Further, the derived polynomial equations predict the double‐K fracture parameters of concrete with negligible error as compared to those obtained based on experimental results.  相似文献   
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An analog topology is proposed to implement a comb filter for removal of power-line interference from various low-amplitude biomedical signals. In this proposed methodology, an n-number of all-pass filters (APFs) and an adder circuit are used to suppress n-number of frequencies. All the APFs as well as the adder circuit are designed using a current conveyor to utilize the various properties of the current-mode circuits. The active and passive components used to design the comb filter include second-generation current conveyor (CCII±), resistor, and capacitor. The circuit is designed for n?=?4 to remove the power-line frequency of 50 Hz, and its three odd harmonics such as 150 Hz, 250 Hz, and 350 Hz. A PSPICE simulation is done to verify the performance of the proposed circuit. In simulation, all CCII±?are designed using macro model of commercially-available current feedback operational amplifier integrated circuit (IC) AD844 as well as dynamic threshold voltage metal oxide semiconductor technology. The proposed circuit is also implemented also using commercially available IC AD844 on breadboard for n?=?3. The output result on digital storage oscilloscope confirm the effectiveness of the proposed comb filter circuit in removing the power line interference i.e. the power-line frequency and its odd harmonics.  相似文献   
25.
Proper fixture design is crucial to workpiece quality assurance in manufacturing. Incorrect fixture design may lead to workpiece deformation during machining. The fixture configuration design is one of the important aspects of fixture design. This paper deals with fixture layout optimization problem. The objective is to minimize the norm of all the passive contact forces satisfying Coulomb friction constraint, work-piece static equilibrium constraint and contact constraint, for the entire cutting operation. To solve this problem, the paper proposes Genetic Algorithm with Learning Automata (GALA) algorithm, which is a population based interconnected learning automata algorithm incorporating genetic operators. The algorithm enjoys the good characteristics of both GA and LA. It is validated with an example of face milling operation. The optimal layout is found to be in tune with empirical facts. Also, for the further investigation of the algorithm, it has been tested on a different problem sets and a comparative study is carried out.  相似文献   
26.
Gelatin (Type B) nanoparticles were prepared by a single W/O emulsion technique and characterized by infrared (IR) spectra, transmission electron micrographs (TEM), surface potential measurements and magnetization studies. Whereas the IR spectra clearly confirmed the presence of gelatin, genipin and doxorubicin in the loaded nanoparticles, the transmission electron micrographs (TEM) image depicts smooth surface, spherical shape and non-uniform size of nanoparticles (up to 100 nm). The prepared nanoparticles were loaded with doxorubicin, a well known anticancer drug, and in vitro release dynamics of entrapped drug was investigated as a function of various experimental factors such as percent loading of the drug, chemical architecture of the nanocarriers, and pH, temperature, ionic strength and nature of the release medium in presence and absence of magnetic field. The nanoparticles were also studied for their water sorption capacity. The drug release process was analyzed kinetically using Ficks power law and a correlation was established between the quantity of released drug and swelling of the nanoparticles.  相似文献   
27.
The Sphaeropsidales, coelomycetous fungi producing asexual conidia within enclosed conidiomata (pycnidia), are saprobic on numerous vascular plants. Despite their ubiquitous nature, only a limited number of genera have been documented as causing human disease. We report what we believe to be the first human case of osteomyelitis due to a Phomopsis species in a chronically immunosuppressed female. The patient developed a subcutaneous abscess on the distal phalanx of the right fourth finger complicated by osteomyelitis. Operative specimens revealed fungal hyphae and a pure culture of mould. The patient was treated with a 6-month course of itraconazole. At 16 months of follow-up, she remained free of recurrence. Phomopsis species differ from the similar, more frequently reported Phoma species by having immersed, thick-walled, multiloculate conidiomata and by the production of alpha (short, ellipsoidal) and beta (long, filamentous) conidia.  相似文献   
28.
Gelatin nanoparticles were prepared by a single W/O emulsion technique and characterized by infrared (IR) spectra, scanning electron microscopy (SEM) and particle size analysis. The prepared nanoparticles were loaded with chloroquine phosphate (CP), a well known antimalarial drug, and the release dynamics of entrapped drug was investigated as a function of various experimental factors such as percent loading of the drug, chemical architecture of the nanocarriers, and pH, temperature, ionic strength and nature of the release medium. The nanoparticles were also studied for their water sorption capacity by optical microscopic method taking advantage of the aggregation of nanoparticles. The drug release processes was analyzed kinetically using Ficks power law and a correlation was established between the quantity of released drug and swelling of the nanoparticles.  相似文献   
29.
A common type of reliability data is the right censored time‐to‐failure data. In this article, we developed a control chart to monitor the time‐to‐failure data in the presence of right censoring using weighted rank tests. On the basis of the asymptotic properties of the rank statistics, we derived the generic formulae for the operating characteristic functions of the control chart to show the relationship between type I error probability, type II error probability, sample size, and hazard rate change. We presented case studies to illustrate the design procedure and the effectiveness of the proposed control chart system. We also investigated and compared the performance of the proposed monitoring procedure with some available monitoring techniques for nonconformities. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
30.
N. Choubey  A. Ojha   《Computer aided design》2007,39(12):1058-1064
The problem of drawing a smooth obstacle avoiding curve has attracted the attention of many people working in the area of CAD/CAM and its applications. In the present paper we propose a method of constrained curve drawing using certain C1-quadratic trigonometric splines having shape parameters, which have been recently introduced in [Han X. Quadratic trigonometric polynomial curves with a shape parameter. Computer Aided Geometric Design 2002;19:503–12]. Besides this, we have also presented a simpler approach for studying the approximation properties of the trigonometric spline curves.  相似文献   
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