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41.
Bifurcation behavior of the buck converter   总被引:8,自引:0,他引:8  
The DC-DC buck power converter, a widely used chopper circuit, exhibits subharmonics and chaos if current feedback is used. This paper investigates the dependence of the system behavior on its parameters. The bifurcation phenomena and a mapping of the parameter space have been presented. This knowledge is vital for designing practical circuits  相似文献   
42.
The paper describes the application of the “equivalent charge distribution method” for designing the geometry of a special type of dipole antenna used for the faithful reproduction of electromagnetic pulse type waveforms. Using this method, the design equation of the surfaces of an asymptotic conical dipole antenna (ACD) has been derived. The surface of the asymptotic conical dipole antenna, obtained by this method, is compared with those computed by the method of Baum (1969). The response of an ACD antenna, fabricated using design data computed from the design equations derived in the paper, is measured and presented  相似文献   
43.
A novel pH‐responsive, chemically crosslinked hydrogelator (cl‐β‐CD/pVP) has been fabricated using β‐cyclodextrin (β‐CD) and N‐vinyl pyrollidone (N‐VP) in presence of diurethane dimethacrylate (DUDMA) crosslinker/azobisisobutyronitrile initiator through free radical polymerization. Various grades of cl‐β‐CD/pVP have been synthesized and the best grade has been considered with higher crosslinking density, higher gel strength, and lower % swelling ratio. The hydrogelator has been characterized by FTIR, 1H and 13C NMR spectroscopy, TGA, and FESEM analyses. The hydrogelator demonstrates pH‐responsive behavior, which has been confirmed by swelling behavior and gel characteristics at various pH (at 37 °C). Using hen egg lysozyme, degradation experiment has been performed, which confirms the biodegradable nature of the hydrogel. The in vitro cytotoxicity study and live–dead assay suggest that the hydrogelator is cytocompatible toward MG‐63 cells. Finally, the hydrogelator shows excellent efficacy as an antibiotic (amoxicillin) carrier. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45939.  相似文献   
44.
The phospholipids of two moss samples Oreoweisia laxifolia (Hookf.) Kindb. (family‐Dicranaceae Schimp.) and Leptodontium viticulosoides (P. Beauv.) Wijk & Margad (family‐Pottiaceae Schimp.) of the Eastern Himalayan Biodiversity Hotspot were investigated to find out any peculiarity in their fatty acid profiles. Detailed analysis of phospholipid classes and the respective fatty acids was performed using high‐performance thin‐layer chromatography and gas chromatography‐mass spectrometry. An array of different saturated and unsaturated fatty acids were detected in both the samples. Although it has been proposed previously that acetylenic fatty acids are associated only with triacylglycerol of storage lipids, the most striking observation of the present investigation is the abundance of an acetylenic fatty acid, octadeca‐6‐yn‐9,12,15‐trienoic acid (18:4a), or Dicranin, in the phospholipids of both the mosses. The position of the triple bond in the hydrocarbon chain of the fatty acids was confirmed by dimethyloxazoline derivatization of fatty acids and their characteristic mass fragmentation pattern. The occurrence of Dicranin in phospholipids and in the Pottiaceae family is reported for the first time, with substantial explanations of the observed results. This may raise the issue of rethinking “Dicranin” as a chemotaxonomic marker of Dicranaceae.  相似文献   
45.
Mobile Networks and Applications - In mobile crowd-sensing, smartphone users take part in sensing and then share the data to the server (cloud) and get an incentive. These data can be utilized for...  相似文献   
46.
Attitude estimation is one of the core frame- works used for navigating an unmanned aerial vehicle from one place to the other. This paper presents an Euler-based non-linear complementary filter (CF) whose gain parameters are obtained using particle swarm optimization (PSO) technique. It relieves the user from feeding the K P and K I parameters manually and adjust these parameters automatically when the error between the attitude measured from accelerometer and the CF increases above a particular threshold. The measurement unit for this research consists of micro-electro-mechanical-systems (MEMS) based low cost tri-axial rate gyros, accelerometers and magnetometers, without resorting to global positioning system (GPS) data. The efficiency of the CF is experimentally investigated with the help of reference attitude and the raw sensor data obtained from commercial inertial measurement unit (IMU). Simulation results based on the test data show that the proposed PSO aided non-linear complementary filter (PNCF) can automatically obtain the required gain parameters and exhibits promising performance for attitude estimation.  相似文献   
47.
Journal of Computational Electronics - The design and performance of digital binary multipliers built using different types of nanoelectronic devices are investigated herein. Designs for...  相似文献   
48.
49.
This study based on Poisson process and orthodox theory of single electron tunneling for the first time proposes an error probability independent delay model for delay calculation of single electronics circuits, involving multiple tunneling events. The Poisson process assumes that the tunneling events are independent of each other, but in real single electronics circuits they are correlated through space and time, so this effect has been considered and included in the proposed model. The dependence of tunneling rates on the logic transition is thoroughly investigated. Finally, the model is applied to different logic gates, and the result is compared with the well known Monte Carlo approach to prove the accuracy of the proposed model.  相似文献   
50.
Adaptive security is a strong security notion that captures additional security threats that are not addressed by static corruptions. For instance, it captures real-world scenarios where “hackers” actively break into computers, possibly while they are executing secure protocols. Studying this setting is interesting from both theoretical and practical points of view. A primary building block in designing adaptively secure protocols is a non-committing encryption (NCE) that implements secure communication channels in the presence of adaptive corruptions. Current constructions require a number of public key operations that grow linearly with the length of the message. Furthermore, general two-party protocols require a number of NCE calls that dependent both on the circuit size and on the security parameter. In this paper, we study the two-party setting in which at most one of the parties is adaptively corrupted, and demonstrate the feasibility of (1) NCE with constant number of public key operations for large message spaces, (2) oblivious transfer with constant number of public key operations for large sender’s input spaces, and (3) constant round secure computation protocols with an overall number of public key operations that is linear in the circuit size. Our study demonstrates that such primitives indeed exist in the presence of single corruptions without erasures, while this is not known for fully adaptive security under standard assumptions (where both parties may get corrupted). Our results are shown in the UC setting with a CRS setup.  相似文献   
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