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排序方式: 共有2393条查询结果,搜索用时 14 毫秒
931.
932.
Ganghee Lee Yongjin Ahn Seokhyun Lee Jeongki Son Kiwook Yoon Kiyoung Choi 《Design Automation for Embedded Systems》2010,14(1):1-20
Memory and communication architecture have a significant impact on the performance, cost, and power of complex multiprocessor system-on-chip designs. In this paper, we present an automated bus matrix synthesis flow for efficient transaction-level design space exploration of communication architecture in a reconfigurable multimedia system-on-chip platform. Specifically, we consider hardware interface selection problem, which has significant effect on the overall cost of area and power. We propose a method to solve such hardware interface selection problem through static analysis of communication behavior. We experiment with JPEG encoder and H.264 encoder examples and the results show the reduction of area by 56.91% and power by 48.61% of bus matrix with 0.58% performance overhead on average compared to the case of maximum performance. According to our HW interface selection algorithm, we also experiment MPEG4 video decoder example. And the result is evaluated on the FPGA prototyping board. 相似文献
933.
We demonstrate that the near field enhancement of sub-wavelength slits can be experimentally determined in the far field by using a reference aperture. Our simple model derived from the Kirchhoff integral formalism shows that enhancement of the near field at a slit exit with respect to the incident wave can be read in the transmitted amplitude through the slit attached on a reference aperture, normalized by the transmitted amplitude through the reference aperture. Furthermore, the near field enhancement obtained in such a way is essentially independent of the reference aperture size. By performing terahertz time domain spectroscopy we experimentally confirm the inverse frequency dependence of the near field enhancement of extremely narrow slits and measure the maximum field enhancement reaching 200 at 0.1 THz for a 500-nm-width slit. 相似文献
934.
We investigate the transport and the dynamical properties of tunnel-coupled double charge shuttles. The oscillation frequencies of two shuttles are mode locked to integer multiples of the applied voltage frequency omega. We show that left-right-symmetric double shuttles may generate direct net current due to bistable motions caused by parametric instability. The symmetry-broken direct current appears near omega = Omega0/(2j-1), (j = 1,2,...), where Omega0 is the dressed resonance frequency of the relative motion of the two shuttles. 相似文献
935.
Abazov VM Abbott B Abolins M Acharya BS Adams M Adams T Agelou M Agram JL Ahn SH Ahsan M Alexeev GD Alkhazov G Alton A Alverson G Alves GA Anastasoaie M Andeen T Anderson S Andrieu B Anzelc MS Arnoud Y Arov M Askew A Asman B Jesus AC Atramentov O Autermann C Avila C Ay C Badaud F Baden A Bagby L Baldin B Bandurin DV Banerjee P Banerjee S Barberis E Bargassa P Baringer P Barnes C Barreto J Bartlett JF Bassler U Bauer D Bean A Begalli M Begel M Belanger-Champagne C Bellantoni L Bellavance A 《Physical review letters》2006,97(11):111801
We present a search for supersymmetry in the R-parity violating resonant production and decay of smuons and muon sneutrinos in the channels mu-->chi(1)(0)mu, mu-->chi(2,3,4)(0)mu, and nu(mu)-->chi(1,2)(+/-)mu. We analyzed 0.38 fb(-1) of integrated luminosity collected between April 2002 and August 2004 with the D0 detector at the Fermilab Tevatron Collider. The observed number of events is in agreement with the standard model expectation, and we calculate 95% C.L. limits on the slepton production cross section times branching fraction to gaugino plus muon, as a function of slepton and gaugino masses. In the framework of minimal supergravity, we set limits on the coupling parameter lambda(211)('), extending significantly previous results obtained in Run I of the Tevatron and at the CERN LEP collider. 相似文献
936.
Choon Ki Ahn 《中国物理 B》2010,19(10):100201-100201
This paper proposes an L2 -L∞ learning law as a new learning method for dynamic neural networks with external disturbance. Based on linear matrix inequality (LMI) formulation, the L2-L∞ learning law is presented to not only guarantee asymptotical stability of dynamic neural networks but also reduce the effect of external disturbance to an L2-L∞ induced norm constraint. It is shown that the design of the L2-L∞ learning law for such neural networks can be achieved by solving LMIs, which can be easily facilitated by using some standard numerical packages. A numerical example is presented to demonstrate the validity of the proposed learning law. 相似文献
937.
Wongi Park Dr. Beatriz Feringán Minyong Yang Seong Ho Ryu Dr. Hyungju Ahn Prof. Dr. Tae Joo Shin Dr. Teresa Sierra Dr. Raquel Giménez Prof. Dr. Dong Ki Yoon 《Chemphyschem》2019,20(6):890-897
Ambipolar organic semiconductors are considered promising for organic electronics because of their interesting electric properties. Many hurdles remain yet to be overcome before they can be used for practical applications, especially because their orientation is hard to control. We demonstrate a method to control the orientation of columnar structures based on a hydrogen (H)-bonded donor-acceptor complex between a star-shaped tris(triazolyl)triazine and triphenylene-containing benzoic acid, using physicochemical nanoconfinement. The molecular configuration and supramolecular columnar assemblies in a one-dimensional porous anodic aluminium oxide (AAO) film were dramatically modulated by controlling the pore-size and by chemical modification of the inner surface of the porous AAO film. In situ experiments using grazing-incidence X-ray diffraction (GIXRD) were carried out to investigate the structural evolution produced at the nanometer scale by varying physicochemical conditions. The resulting highly ordered nanostructures may open a new pathway to effectively control the alignment of liquid crystal ambipolar semiconductors. 相似文献
938.
Armin Darvish Jung Soo Lee Bin Peng Jugal Saharia Ramalingam VenkatKalyana Sundaram Gaurav Goyal Nuwan Bandara Chi Won Ahn Jungsuk Kim Prashanta Dutta Irwin Chaiken Min Jun Kim 《Electrophoresis》2019,40(5):776-783
Enveloped viruses fuse with cells to transfer their genetic materials and infect the host cell. Fusion requires deformation of both viral and cellular membranes. Since the rigidity of viral membrane is a key factor in their infectivity, studying the rigidity of viral particles is of great significance in understating viral infection. In this paper, a nanopore is used as a single molecule sensor to characterize the deformation of pseudo‐type human immunodeficiency virus type 1 at sub‐micron scale. Non‐infective immature viruses were found to be more rigid than infective mature viruses. In addition, the effects of cholesterol and membrane proteins on the mechanical properties of mature viruses were investigated by chemically modifying the membranes. Furthermore, the deformability of single virus particles was analyzed through a recapturing technique, where the same virus was analyzed twice. The findings demonstrate the ability of nanopore resistive pulse sensing to characterize the deformation of a single virus as opposed to average ensemble measurements. 相似文献
939.
Milan K. Sadan Seon-Hwa Choi Hui Hun Kim Changhyeon Kim Gyu-Bong Cho Ki-Won Kim N. S. Reddy Jou-Hyeon Ahn Hyo-Jun Ahn 《Ionics》2018,24(3):753-761
To determine the effect of electrolyte salts on the cycling properties of tin anodes in sodium ion batteries, sodium/tin cells were prepared using eight electrolytes containing NaCF3SO3, NaBF4, NaClO4, and NaPF6 in ethylene carbonate-dimethyl carbonate (EC-DMC) and EC-DMC/fluoroethylene carbonate (FEC) solvents. The first charge capacity and cycling properties strongly depended on the electrolyte salts. Additionally, an appropriately chosen electrolyte salt in combination with the FEC additive improved the cycling properties of the tin electrode. The tin electrode in the presence of the FEC-containing NaPF6-based electrolyte exhibited the best cycling properties. The first charge capacity and charge capacity after the 45th cycle were 220 and 189 mAh g?1 electrode, respectively at a current density of 84.7 mA g?1 electrode. The rate performance is also studied using the optimized electrolyte which reveals the ability of the electrode to perform in high current application. At a high current density of 4235 mA g?1 electrode, the capacity delivered is 24 mAh g?1 electrode. At a current rate of 1694 mA g?1 electrode, at the end of 1400th cycle, capacity is about 45 mAh g?1 electrode. The results of the study clearly indicate that the electrolyte salts critically affect the electrochemical performance of the tin anode in sodium ion batteries. 相似文献
940.
A. D. Panov J. H. Adams Jr. H. S. Ahn G. L. Bashinzhagyan J. W. Watts J. P. Wefel J. Wu O. Ganel T. G. Guzik V. I. Zatsepin I. Isbert K. C. Kim M. Christl E. N. Kouznetsov M. I. Panasyuk E. S. Seo N. V. Sokolskaya J. Chang W. K. H. Schmidt A. R. Fazely 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(5):564-567
The final results of processing the data from the balloon-born experiment ATIC-2 (Antarctica, 2002–2003) for the energy spectra of protons and He, C, O, Ne, Mg, Si, and Fe nuclei, the spectrum of all particles, and the mean logarithm of atomic weight of primary cosmic rays as a function of energy are presented. The final results are based on improvement of the methods used earlier, in particular, considerably increased resolution of the charge spectrum. The preliminary conclusions on the significant difference in the spectra of protons and helium nuclei (the proton spectrum is steeper) and the non-power character of the spectra of protons and heavier nuclei (flattening of carbon spectrum at energies above 10 TeV) are confirmed. A complex structure of the energy dependence of the mean logarithm of atomic weight is found. 相似文献