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991.
Sang-Ryeol Park Won-Pil Baek Soon-Heung Chang Byung-Ho Lee 《Nuclear Engineering and Design》1992,135(3)
A statistical uncertainty quantification methodology for evaluation of the emergency core cooling system (ECCS) performance is proposed and applied in assessing the best-estimate peak cladding temperature (PCT). In the proposed methodology, the Latin hypercube sampling method is adopted, and separate model uncertainties are used as input variables. The independency of the input variables is verified through a correlation coefficient test for statistical treatment of their uncertainties. Next, the PCT response distribution is determined through a goodness-of-fit test. Finally, the PCT with a one-sided 95% probability and a confidence level of 0.95 is estimated.This methodology is applied to the large-break loss-of-coolant accident (LBLOCA) of Kori Nuclear Units 3 and 4. This study shows that the proposed methodology is a useful one. 相似文献
992.
993.
Seung-Cheol Baek Soon-Bum Kwon Toshiaki Setoguchi Heuy-Dong Kim 《Journal of Mechanical Science and Technology》2002,16(11):1511-1521
High-speed moist air or steam flow has long been of important subject in engineering and industrial applications. Of many
complicated gas dynamics problems involved in moist air flows, the most challenging task is to understand the nonequilibrium
condensation phenomenon when the moist air rapidly expands through a flow device. Many theoretical and experimental studies
using supersonic wind tunnels have devoted to the understanding of the nonequilibrium condensation flow physics so far. However,
the nonequilibrium condensation can be also generated in the subsonic flows induced by the unsteady expansion waves in shock
tube. The major flow physics of the nonequilibrium condensation in this application may be different from those obtained in
the supersonic wind tunnels. In the current study, the nonequilibrium condensation phenomenon caused by the unsteady expansion
waves in a shock tube is analyzed by using the two-dimensional, unsteady, Navier-Stokes equations, which are fully coupled
with a droplet growth equation. The third-order TVD MUSCL scheme is applied to solve the governing equation systems. The computational
results are compared with the previous experimental data. The time-dependent behavior of nonequilibrium condensation of moist
air in shock tube is investigated in details. The results show that the major characteristics of the nonequilibrium condensation
phenomenon in shock tube are very different from those in the supersonic wind tunnels. 相似文献
994.
Kwang Suk Jung Yoon Su Baek 《IEEE transactions on magnetics》2002,38(3):1539-1548
In this paper, we introduce a contact-free moving-magnet type of positioner that uses magnetic levitation to eliminate friction, the major limiting factor to high resolution on the micromanufacturing level. The promising magnetic structure consists of permanent magnets mounted on the stage and air-core solenoids, with little uncertainty, fixed on the stator. Since magnetically levitated systems are inherently unstable, the design concept focuses on stability. Combining the above elements with the repulsive force property, we suggest a novel six degrees-of-freedom Maglev positioner stabilized with minimum sensory feedback in space and have formulated the dynamic equation of the system by the linear perturbation technique. The chief design parameters are optimized to maximize the stable boundary. We present test results to verify the dynamic characteristics 相似文献
995.
Dae Kim Je Baek Jae-Kyoon Kim Sang Hyun Yoon Park 《Communications, IEEE Transactions on》1987,35(2):142-150
Techniques for varying duobinary and modified duobinary, which are two of the most important partial-response codes, to limit their run lengths without destroying their minimum bandwidth property, are introduced. One of the example codes is the first run-length-limited variant of duobinary ever known, and the other two are already publicized variants of modified duobinary, but are described either in more detail or from a different point of view. Performance figures of the three codes such as power spectrum, eye width, and error probability are experimentally confirmed to be acceptable for all engineering purposes. 相似文献
996.
Gh: a GTP-binding protein with transglutaminase activity and receptor signaling function 总被引:1,自引:0,他引:1
H Nakaoka DM Perez KJ Baek T Das A Husain K Misono MJ Im RM Graham 《Canadian Metallurgical Quarterly》1994,264(5165):1593-1596
The alpha 1-adrenergic receptors activate a phospholipase C enzyme by coupling to members of the large molecular size (approximately 74 to 80 kilodaltons) G alpha h family of guanosine triphosphate (GTP)-binding proteins. Rat liver G alpha h is now shown to be a tissue transglutaminase type II (TGase II). The transglutaminase activity of rat liver TGase II expressed in COS-1 cells was inhibited by the nonhydrolyzable GTP analog guanosine 5'-O-(3-thiotriphosphate) or by alpha 1-adrenergic receptor activation. Rat liver TGase II also mediated alpha 1-adrenergic receptor stimulation of phospholipase C activity. Thus, G alpha h represents a new class of GTP-binding proteins that participate in receptor signaling and may be a component of a complex regulatory network in which receptor-stimulated GTP binding switches the function of G alpha h from transglutamination to receptor signaling. 相似文献
997.
Park JH Lee Y Moon E Seok SH Cho SA Baek MW Lee HY Kim DJ Park JH 《Journal of food protection》2005,68(3):571-576
The immunoenhancing effects of Lactobacillus fermentum PL9005 were assessed via mouse intragastric inoculation. The number of immunoglobulin A-positive cells in the small intestine, CD4+ T lymphocytes in the peripheral blood, and the lymphocyte proliferation response to mitogen stimulation (lipopolysaccharide) increased in mice fed L. fermentum PL9005. The lactic acid concentration also increased dose dependently in the small intestine of mice fed L. fermentum PL9005. No differences were found in body weight, food intake, and clinical signs between mice fed L. fermentum PL9005 and the control group. Results indicated that L. fermentum PL9005 is a probiotic with immunoenhancing properties. 相似文献
998.
W values of tissue-equivalent gases based on propane and butane were measured for protons in the energy range 1-100 keV and compared with those of dimethylether and water vapour. The experimental values of the tissue-equivalent gas mixtures were compared with data calculated from the W values of the mixture components using five existing additivity models and two new models derived within the scope of the present work. Apart from one model--the simplest one--all models show a good agreement with the experimental data. 相似文献
999.
Multiwavelength Lasers for WDM-PON Optical Line Terminal Source by Silica Planar Lightwave Circuit Hybrid Integration 总被引:1,自引:0,他引:1
Su Hwan Oh Yoon-Jung Park Sung-Bock Kim Sahnggi Park Hee-Kyung Sung Yong-Soon Baek Kwang-Ryong Oh 《Photonics Technology Letters, IEEE》2007,19(20):1622-1624
We have demonstrated a very compact eight-channel 200-GHz-spacing multiwavelength laser (MWL) module for the optical line terminal source of wavelength-division-multiplexing passive optical network. The wavelength shift of MWLs and external cavity lasers from the ITU grid was within +0.14 nm for eight channels, which was well matched to the target wavelength shift of less than plusmn0.2 nm. The oscillation characteristics of our MWL module are better than those of conventional MWLs with hybrid integration. 相似文献
1000.
Cancer is a disorder of cell growth and proliferation, characterized by different metabolic pathways within normal cells. The Warburg effect is a major metabolic process in cancer cells that affects the cellular responses, such as proliferation and apoptosis. Various signaling factors down/upregulate factors of the glycolysis pathway in cancer cells, and these signaling factors are ubiquitinated/deubiquitinated via the ubiquitin–proteasome system (UPS). Depending on the target protein, DUBs act as both an oncoprotein and a tumor suppressor. Since the degradation of tumor suppressors and stabilization of oncoproteins by either negative regulation by E3 ligases or positive regulation of DUBs, respectively, promote tumorigenesis, it is necessary to suppress these DUBs by applying appropriate inhibitors or small molecules. Therefore, we propose that the DUBs and their inhibitors related to the Warburg effect are potential anticancer targets. 相似文献