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181.
Ji-Hoon Lee Yun-Joo Nam Myeong-Kwan Park 《Journal of Mechanical Science and Technology》2010,24(1):19-23
This paper presents a two degree-of-freedom (DOF) planar parallel manipulator with two linear actuators, whose degree of freedom
is dependent on a passive constraining leg connecting the base and the platform. The kinematics of the presented manipulator
is first studied: the inverse and forward kinematics problems are solved in the closed form, the practical workspace is described
symbolically, the Jacobian matrix is derived, and several singular conditions are discussed. Then, in order to determine the
geometric parameters and the operating range of the actuators, the optimization of the mechanism is performed considering
its dexterity and stiffness. 相似文献
182.
A highly linear, low noise differential down-converter employing a new linearisation technique derived from composite transistors, i.e. nMOSFET and vertical NPN BJT, is proposed and implemented in a 0.18 μm CMOS technology. It draws 1 mA from a 2.5 V supply voltage and has a voltage gain of 13 dB, a double-sideband noise figure of 9.5 dB, an IIP2 of more than 49 dBm, and an IIP3 of 6.5 dBm. 相似文献
183.
Summary
The new polyarylenevinylene, structurally based on a terstyryl group linked by a maleimide group, was prepared from a new
dibrominated diphenylmaleimide monomer and p-divinylbenzene by Heck-type Pd catalyzed polycondensation. The polymer was soluble in common organic solvents and had M
w and the polydispersity index of 73,600 g/mol and 5.0, respectively. Analysis with IR and NMR indicated that the polymer had
a stereoregular vinylene sequence in the backbone of Z, E, E-configurations in series. The polymer showed optical absorption maximums at 353 nm and 444 nm and the bright orange red-colored
photoluminescence at 570 nm in a solution and 590 nm in a film.
Received: 19 September 2000/Revised version: 4 December 2000/Accepted: 11 December 2000 相似文献
184.
Jaeeun Lee Siwook Park Hwangsun Kim Seong-Jun Park Keunho Lee Mi-Young Kim Phaniraj P. Madakashira Heung Nam Han 《Metals and Materials International》2018,24(4):702-710
Fe–Al–Mn–C alloy systems are low-density austenite-based steels that show excellent mechanical properties. After aging such steels at adequate temperatures for adequate time, nano-scale precipitates such as κ-carbide form, which have profound effects on the mechanical properties. Therefore, it is important to predict the amount and size of the generated κ-carbide precipitates in order to control the mechanical properties of low-density steels. In this study, the microstructure and mechanical properties of aged low-density austenitic steel were characterized. Thermo-kinetic simulations of the aging process were used to predict the size and phase fraction of κ-carbide after different aging periods, and these results were validated by comparison with experimental data derived from dark-field transmission electron microscopy images. Based on these results, models for precipitation strengthening based on different mechanisms were assessed. The measured increase in the strength of aged specimens was compared with that calculated from the models to determine the exact precipitation strengthening mechanism. 相似文献
185.
186.
Effects of rice koji inoculated with Aspergillus luchuensis on the biochemical and sensory properties of a sailfin sandfish (Arctoscopus japonicus) fish sauce
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Byoung‐Mok Kim Jae‐Ho Park Dong‐Soo Kim Young‐Myung Kim Joon‐Young Jun In‐Hak Jeong Si‐Youl Nam Young‐Min Chi 《International Journal of Food Science & Technology》2016,51(8):1888-1899
The effects of rice koji inoculated with Aspergillus luchuensis on the biochemical and sensory properties of fish sauce produced from sailfin sandfish (Arctoscopus japonicus) with different salt concentrations (10% and 20%) were investigated over 10 months. Fish sauces prepared from sailfin sandfish with rice koji and a low salt concentration had higher total nitrogen, amino nitrogen and total free amino acid than did those without rice koji or with a high salt concentration. Sensory evaluation of fish sauces prepared with rice koji and a low salt concentration found better taste, flavour and overall acceptance than those prepared without rice koji during fermentation (P < 0.05). The use of rice koji increased the total nitrogen, amino nitrogen and free amino acid and also enhanced the sensory qualities during fermentation. These results suggest that the use of rice koji can result in a low‐salt fish sauce with better flavour. 相似文献
187.
188.
There has been increasing interest in clean energy over past few years. Ocean Thermal Energy Conversion (OTEC) power plants have been examined as a viable option for supplying clean energy. This paper evaluated the thermodynamic performance of the OTEC power system. Computer simulation programs were developed under the same conditions but with various working fluids for a closed system, a regeneration system, an open system, a Kalina system, and a hybrid system. The results showed that the regeneration system using R125 showed a 0.17 to 1.56% increase in system efficiency. Moreover, the system can generate electricity when the difference in temperature between the warm and cold seawater inlet temperatures is greater than 15 °C. In addition, the system efficiency of OTEC power plants using the condenser effluent from a nuclear power plant instead of surface water was increased by approximately 2%. 相似文献
189.
190.