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51.
Ho-Lim Choi Hee-Jung Byun Won-Gyu Song Jun-Won Son Jong-Tae Lim 《Artificial Life and Robotics》2000,4(4):193-197
We present a method to calssify electromyogram (EMG) signals which are utilized as control signals for a patient-responsive
walker-supported system for paraplegics. Patterns of EMG signals for different walking motions are classified via adequate
filtering, real EMG signal extraction, AR-modeling, and a modified self-organizing feature map (MSOFM). In particular, a data-reducing
extraction algorithm is employed for real EMG signals. Moreover, MSOFM classifies and determines the results automatically
using a fixed map. Finally, the experimental results are presented for validation. 相似文献
52.
Junggeun Jhin Jong Hyeob Baek Dongjin Byun 《Journal of the Society for Information Display》2008,16(4):535-539
Abstract— The structural, electrical, and optical properties of GaN epilayers grown on various ion‐implanted sapphire(0001) substrates by MOCVD were investigated. GaN or AlN buffer layers and pre‐treatment were indispensably introduced before GaN‐epilayer growth. The ion‐implanted substrate's surface had decreased internal free energies during the growth of the ion‐implanted sapphire(0001) substrates. The crystal and optical properties of the GaN epilayers grown in ion‐implanted sapphire(0001) substrates were improved. Also, an excessively roughened and modified surface caused by ions degraded the GaN epilayers. Not only the ionic radius but also the chemical species of implanted sapphire(0001) substrates improved the properties of the GaN epilayers grown by MOCVD. It is obvious that the ion‐implanted pre‐treatment of sapphire(0001) substrates can be an alternative pre‐treatment procedure for GaN deposition and has the potential to improve the properties of the GaN epilayers on sapphire(0001) substrates. 相似文献
53.
In this paper, interface circuits that are suitable for point‐to‐point interconnection with an over 1 Gbps data rate per pin are proposed. To achieve a successful data transfer rate of multi‐gigabits per‐second between two chips with a point‐to‐point interconnection, the input receiver uses an on‐chip parallel terminator of the pass gate style, while the output driver uses the pullup and pulldown transistors of the diode‐connected style. In addition, the novel dynamic voltage level converter (DVLC) has solved such problems as the access time increase and valid data window reduction. These schemes were adopted on a 64 Mb DDR SRAM with a 1.5 Gbps data rate per pin and fabricated using a 0.10 µm dual gate oxide CMOS technology. 相似文献
54.
Seung Wook Yoon Jun Ki Hong Hwa Jung Kim Kwang Yoo Byun 《Electronics Packaging Manufacturing, IEEE Transactions on》2005,28(2):168-175
To evaluate various Pb-free solder systems for leaded package, thin small outline packages (TSOPs) and chip scale packages (CSPs) including leadframe CSP (LFCSP), fine pitch BGA (FBGA), and wafer level CSP (WLCSP) were characterized in terms of board level and mechanical solder joint reliability. For board level solder joint reliability test of TSOPs, daisy chain samples having pure-Sn were prepared and placed on daisy chain printed circuit board (PCB) with Pb-free solder pastes. For CSPs, the same composition of Pb-free solder balls and solder pastes were used for assembly of daisy chain PCB. The samples were subjected to temperature cycle (T/C) tests (-65/spl deg/C/spl sim/150/spl deg/C, -55/spl deg/C/spl sim/125/spl deg/C, 2 cycles/h). Solder joint lifetime was electrically monitored by resistance measurement and the metallurgical characteristics of solder joint were analyzed by microstructural observation on a cross-section sample. In addition, mechanical tests including shock test, variable frequency vibration test, and four point twisting test were carried out with daisy chain packages too. In order to compare the effect of Pb-free solders with those of Sn-Pb solder, Sn-Pb solder balls and solder paste were included. According to this paper, most Pb-free solder systems were compatible with the conventional Sn-Pb solder with respect to board level and mechanical solder joint reliability. For application of Pb-free solder to WLCSP, Cu diffusion barrier layer is required to block the excessive Cu diffusion, which induced Cu trace failure. 相似文献
55.
Woo‐Jin Byun Bong‐Su Kim Kwang Seon Kim Ki‐Chan Eun Myung‐Sun Song Reinhard Kulke Olaf Kersten Gregor Möllenbeck Matthias Rittweger 《ETRI Journal》2010,32(2):195-203
A new vertical transition between a substrate integrated waveguide in a low‐temperature co‐fired ceramic substrate and an air‐filled standard waveguide is proposed in this paper. A rectangular cavity resonator with closely spaced metallic vias is designed to connect the substrate integrated waveguide to the standard air‐filled waveguide. Physical characteristics of an air‐filled WR‐22 to WR‐22 transition are compared with those of the proposed transition. Simulation and experiment demonstrate that the proposed transition shows a ?1.3 dB insertion loss and 6.2 GHz bandwidth with a 10 dB return loss for the back‐to‐back module. A 40 GHz low‐temperature co‐fired ceramic module with the proposed vertical transition is also implemented. The implemented module is very compact, measuring 57 mm × 28 mm × 3.3 mm. 相似文献
56.
Kim Da Hyun Kim Jae Hwan Kim Da Hyun Jo Jay-Young Byun Sanguine 《Food science and biotechnology》2022,31(5):527-538
Food Science and Biotechnology - Viruses are known to cause a variety of diseases, ranging from mild respiratory diseases, such as the common cold, to fatal illnesses. Although the development of... 相似文献
57.
Refrigerant R-410a flow distribution is experimentally studied in a test section simulating a minichannel heat exchanger having vertical headers with two pass configuration. Tubes are heated to yield a test section outlet superheat of 5°C with inlet quality of 0.3. Mass flux is varied from 60 kg/m2-s to 70 kg/m2-s. Effects of outlet locations are investigated in a search for an optimum configuration. The effect of varying the number of tubes of each pass is also investigated. Results show that significant liquid flows through bottom channels, and less liquid is supplied to top channels. For the outlet location, a bottom outlet is better than a middle or top outlet. In addition, assigning a lower number of tubes to inlet pass yields better flow distribution. Correlations are developed for the fraction of liquid or gas taken off by the downstream channel as a function of header gas Reynolds number immediately upstream. The correlations may be used to predict the liquid or gas distribution in a parallel-flow heat exchanger havin vertical headers. 相似文献
58.
Hwack Joo Lee Hyun Ryu Hyun Min Park Jong Hoo Paik Sahn Nahm Jae-Dong Byun 《Journal of the American Ceramic Society》1998,81(6):1685-1688
Microstructural studies on the interfacial boundaries of 1:1 and 1:2 ordered domains in (Ba0.9 La0.1 )(Mg0.37 Nb0.63 )O3 were conducted using high-resolution transmission electron microscopy and X-ray diffractometry. Both 1:2 and 1:1 ordered domains coexisted in a fully ordered single grain. Each ordered domain occupied its own region, and the interfaces were atomically sharp and coherent. The wavelength of the superlattice modulation was ∼0.47 nm in the 1:1 ordered domain and ∼0.71 nm in the 1:2 ordered domain. The transition from the 1:2 ordered region to the 1:1 ordered region was clearly shown at the interface. These observations well support the structural models that have been previously presented. 相似文献
59.
Ki Yeol Byun Isabelle FerainJohn Hayes Ran Yu Farzan Gity Cindy Colinge 《Microelectronic Engineering》2011,88(4):522-525
In this work, an alternative method for producing the single crystalline Ge-Si Avalanche photodiodes (APD) with low thermal budget was investigated. Structural and electrical investigations show that low temperature Ge to Si wafer bonding can be used to achieve successful APD integration. Based on the surface chemistry of the Ge layer, the buried interfaces were investigated using high resolution transmission electron microscopy as a function of surface activation after low temperature annealing at 200 and 300 °C. The hetero-interface was characterized by measuring forward and reverse currents. 相似文献
60.
Eight representative types of juk (Korean traditional congee) cooked with seafood, and plain juk were analyzed for biogenic amine content. Results revealed that while plain juk contains no biogenic amines, juk prepared with seafood has a high level of histamine, ranging from 120 to 170 mg/kg. The seafood used in juk preparation contained different concentrations of histamine, ranging from 60 to 300 mg/kg. No other biogenic amines were detected in most juk and seafood samples. The bacterial contribution to the biogenic amine content in selected seafood was evaluated by analyzing the bacterial distribution and ability to produce biogenic amines. Strains of Achromobacter, Staphylococcus, and Micrococcus that are capable of producing biogenic amines are the dominant genera in the seafood tested. Therefore, this study suggests that the levels of dominant bacteria need to be controlled to reduce the amounts of biogenic amines in seafood and, thereby, in juk prepared with seafood. 相似文献