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51.
Hakho Lee Yong Liu Westervelt R.M. Ham D. 《Solid-State Circuits, IEEE Journal of》2006,41(6):1471-1480
This paper introduces an integrated circuit (IC)/microfluidic hybrid system for magnetic manipulation of biological cells. The hybrid system consists of an IC and a microfluidic system fabricated on top. Biological cells attached to magnetic beads are suspended inside the microfluidic system that maintains biocompatibility. The IC contains a microcoil array circuit that produces spatially-patterned microscopic magnetic fields. Programmable, rapid reconfiguration of the field pattern made possible by the IC allows an efficient simultaneous manipulation of multiple individual bead-bound cells with precise position control. Two prototypes, SiGe/microfluidic and CMOS/microfluidic hybrid systems, validate the proposed approach. 相似文献
52.
A new method for detecting fluctuations in the fundamental frequency component of a power system, by relating it to a leakage coefficient in the FFT, is presented. The phenomenon of leakage in the FFT is used advantageously to increase spectral resolution. The leakage coefficient is a quantitative measure of the deviation from the fundamental frequency component with respect to the sampling frequency. Theoretical aspects are considered along with a method for on-line implementation. 相似文献
53.
Robinson James W. Ham Mooyoung 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1975,3(4):222-226
Zinc ion pulses with varying amplitudes up to 1 mA have been extracted from a vacuum discharge. Repetitive operation of the pulsed discharge at 5300 Hz was maintained for 24 min. Breakdown of the 0.4 mm vacuum gap was accomplished by ramp-charging a 270 pF capacitor connected across the gap until breakdown occurred, the capacitor then being discharged through the gap. Stable operation was maintained by feedback control of the electrode spacing. The anode was eroded at 10 mg/C by the discharge, with 65 percent of the anode material being deposited on the cathode in the form of a fiber. 相似文献
54.
三端双向晶闸管用于控制AC电源负载。在大多数应用中,三端双向晶闸管会消耗大量电能,因而需要考虑散热。同时必须计算散热器的大小并预测最高结点温度Tjmax。散热设计和分析是设计和开发过程的基本部分。散热设计需要几个计算阶段,涉及到功率、热阻和温度升高。本文介绍的便是这些计算。 相似文献
55.
P.H. Cannington Norman S. Ham 《Journal of Electron Spectroscopy and Related Phenomena》1979,15(1):79-82
Photoelectron spectra, excited by He I radiation, of the following amino acids were measured:- alanine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, histidine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophane, tyrosine, 4-hydroxyproline, β-alanine, γ-aminobutyric acid and δ-aminovaleric acid. The spectra showed a number of bands of low ionization energy (<13 eV) and these have been assigned to photoionizations from the NH2 and COOH groups. For the α-amino acids with complex side-chains extra bands arising from easily-ionizable electrons in aromatic rings or atomic lonepairs, such as sulphur or oxygen atoms, were also identified. Perturbation arguments together with the spectra of closely related molecules have been used to confirm the assignments. During measurement, decomposition occurred for aspartic acid, asparagine and histidine, while glutamic acid and glutamine cyclized. 相似文献
56.
Reaction of cyclohexadienylium-Fe(CO)3 complexes (7) and (8) with sodiomalono-nitrile gives the carbo-spirocyclic derivatives (9) and (10), whilst reaction with benzylamine and removal of iron leads to the azaspirocyclic enones (15) and (16), respectively. 相似文献
57.
Subluminal and superluminal propagation in Er<Superscript>3+</Superscript> doped fiber Bragg grating
Z. C. Zhuo B. S. Ham 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,49(1):117-121
The method to pump the FBG written into an Er3+-doped optical fiber is proposed to decrease or increase the group velocity of a probing pulse based on the fact that a pump-induced
process changes the refractive index and dispersion associated with the 4I15/2-4I13/2 transition in Er3+-doped optical fiber. The system equations are derived. The group velocity modification is numerically demonstrated and discussed
with the effects of an optical pump power, fiber Bragg grating length, doping concentration of Er3+ ions, and modulation amplitude of the grating. 相似文献
58.
We present a general information theoretic approach for identifying functional subgraphs in complex networks. We show that the uncertainty in a variable can be written as a sum of information quantities, where each term is generated by successively conditioning mutual informations on new measured variables in a way analogous to a discrete differential calculus. The analogy to a Taylor series suggests efficient optimization algorithms for determining the state of a target variable in terms of functional groups of other nodes. We apply this methodology to electrophysiological recordings of cortical neuronal networks grown in vitro. Each cell's firing is generally explained by the activity of a few neurons. We identify these neuronal subgraphs in terms of their redundant or synergetic character and reconstruct neuronal circuits that account for the state of target cells. 相似文献
59.
We have demonstrated electromagnetically induced transparency (EIT) in an inhomogeneously broadened spectral hole-burning system of Pr(3+)-doped Y(2)SiO(5) at 6 K. We have also shown enhancement of four-wave mixing under conditions of reduced absorption. This demonstration opens the possibilities of pursuing EIT applications such as high-resolution optical image processing and optical data storage in solids. 相似文献
60.
Yong Cheol Peter Cho Jaehoon Chung Jeongmin Yang Chun‐Gi Lyuh HyunMi Kim Chan Kim Je‐seok Ham Minseok Choi Kyoungseon Shin Jinho Han Youngsu Kwon 《ETRI Journal》2020,42(4):491-504
We present AB9, a neural processor for inference acceleration. AB9 consists of a systolic tensor core (STC) neural network accelerator designed to accelerate artificial intelligence applications by exploiting the data reuse and parallelism characteristics inherent in neural networks while providing fast access to large on‐chip memory. Complementing the hardware is an intuitive and user‐friendly development environment that includes a simulator and an implementation flow that provides a high degree of programmability with a short development time. Along with a 40‐TFLOP STC that includes 32k arithmetic units and over 36 MB of on‐chip SRAM, our baseline implementation of AB9 consists of a 1‐GHz quad‐core setup with other various industry‐standard peripheral intellectual properties. The acceleration performance and power efficiency were evaluated using YOLOv2, and the results show that AB9 has superior performance and power efficiency to that of a general‐purpose graphics processing unit implementation. AB9 has been taped out in the TSMC 28‐nm process with a chip size of 17 × 23 mm2. Delivery is expected later this year. 相似文献