• Journal of the Korean Geosynthetics Society
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• v.15 no.3
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• pp.1-12
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• 2016

In this study, the impact of sand and weathered granite soil is analyzed by changing the internal temperature from $20^{\circ}C{\sim}70^{\circ}C$C by installing a heating coil inside the triaxial cell. To check the effect on weathered granite soil due to increase of temperature and number of heating-coiling cycles are analyzed by measuring the temperature by using thermometer installed inside the triaxial cell and due to that deviator stress also occurred during the consolidated undrained test. To analyze the effect of weathered granite soil with change of temperature during undrained testing. The deviator stress and pore pressure is measured. As a result, pore pressure increases and the deviator stress decreases with rise of temperature.

• Food Science of Animal Resources
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• v.38 no.4
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• pp.679-692
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• 2018

The effects of high-pressure processing (HPP) treatment on the quality characteristics of low graded Hanwoo beef marinated with five different sauces (soy, fish, fish-soy, soy-fish and fish-soy-meat sauces) obtained from Asian countries were studied. The Hanwoo beef striploins were marinated with the aforementioned sauces (at ratio: 3:1 w/w) for 3 days at $4^{\circ}C$ before they were treated with HPP at 550 MPa for 5 min at $10^{\circ}C$. All the sauces used were equalized to a same salt level of 12.5%, and the samples marinated with a 12.5% brine solution were served as a control. After treating with the HPP, all the samples were stored for further 7 days at $4^{\circ}C$ for analyses. Results revealed that HPP treatments showed some effects on technological quality traits (pH, cooking loss and color) but had no effect on the collagen contents of the marinated beef. Noticeably, the HPP treatment led to the increases in amounts of free amino acids associated with monosodium glutamate-like taste and sweet taste in the samples marinated with fish sauce or soy-fish sauce, fish-soy sauce and fish-soy-meat sauce whereas, it only reduced these amino acids in the samples marinated with soy sauce or control. Furthermore, the total bacteria count in all the marinated beef samples treated with HPP were significantly (p<0.05) lower than those of the non-HPP-treated samples throughout the storage periods. It is concluded that HPP could be applied for enhancing the taste-active compounds production such as free amino acids, and improving the shelflife stability of the marinated beef.

• Proceedings of the Optical Society of Korea Conference
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• 2009.02a
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• pp.133-134
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• 2009

Cold temperature development (CTD) of electron beam (EB) patterned resists and subsequent dry etching were investigated for fabrication of nano-patterned Niobium (Nb). Bulky Nb fims on GaAs substrates were deposited with EB evaporation. Line patterns on Nb cathode were fabricated by EB patterning and reactive ion etching (RIE). Size deviations of nano-sized line patterns from CAD designed patterns are dependent on the EB total exposure, but it can be improved by CTD of EB-exposed resist. Line patterns of 10 to 300 nm widths of EB-exposed resist patterns were drawn under various exposure conditions of $0.2{\mu}s$/dot (total 240,000 dot) with a constant current (50 pA). Compared with room temperature development (RTD), the CTD improves pattern resolution due to the suppression of backscattering effect. RIE with $CF_4$ was performed for formation of several nano-sized line patterns on Nb. Each EB-resist patterned samples with RTDs and CTDs were etched with two different $CF_4$ gas pressures of 5 Pa. Nb etching rate increases while GaAs (or ZEP) etching rate decreases as the chamber pressure increases. This different dependent of the etching rate on the $CF_4$ pressure between Nb and GaAs (or ZEP) has a significant meaning because selective etching of nano-sized Nb line patterns is possible without etching of the underlying active layer.

• Journal of computational fluids engineering
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• v.10 no.3 s.30
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• pp.9-18
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• 2005

During a hypothetical severe accident in a nuclear power plant (NPP), hydrogen is generated by the active reaction of fuel-cladding and steam in the reactor pressure vessel and released with steam into the containment. In order to mitigate hydrogen hazards possibly occurred in the NPP containment, hydrogen mitigation system (HMS) is usually adopted. The design of the next generation NPP (APR1400) designed in Korea specifies 26 passive autocatalytic recombiners and 10 igniters installed in the containment for the hydrogen mitigation. in this study, the analysis of the hydrogen and steam behavior during a total lose of feed water (TLOFW) accident in the APR1400 containment has been conducted by using the CFD code GASFLOW. During the accident, a huge amount of hot water, steam, and hydrogen is released in the in-containment refueling water storage tank (IRWST). The current design of the APR1400 includes flap-type dampers at the IRWST vents which are operated depending on the pressure difference between inside and outside of the IRWST. it was found that the flaps strongly affects the flow structure of the steam and hydrogen in the containment. The possibilities of a flame acceleration and transition from deflagration to detonation (DDT) were evaluated by using Sigma-Lambda criteria. Numerical results indicate the DDT possibility could be heavily reduced in the IRWST compartment when the flaps are installed.

• The Journal of Internal Korean Medicine
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• v.39 no.4
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• pp.624-636
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• 2018

Objectives: The purpose of this study was to investigate the cardioprotective effect of the potent antioxidant properties of Scrophulariae Radix (SR) aqueous extracts by examining pressure overload (PO) heart failure (HF) induced by transverse aortic constriction (TAC) of C57BL/6 mice. Methods: SR (500, 250, 125 mg/kg) and resveratrol (10 mg/kg) were administered orally once a day for 14 days, after the TAC operation. Changes in mortality, the body and heart weights, histopathology of the heart, and antioxidant defense system of the heart were analyzed. Results: After the TAC operation, increases were observed in mortality, heart weights, left ventricular hypertrophy, and lytic and focal fibrotic histological change, and destruction of the heart antioxidant defense system. However, the HF signs showed dose-dependent inhibition following 14 days of continuous oral treatment with SR. A SR dose of 125 mg/kg gave a similar inhibition to that obtained with resveratrol at 10 mg/kg. Conclusions: Oral administration of SR beneficially improves PO-induced HF following TAC surgery by increasing the activity of the heart antioxidant defense system. The overall effect of SR at 125 mg/kg is similar to the effect of resveratrol at 10 mg/kg. However, more detailed mechanistic studies should be performed by screening of the biologically active compounds in SR.

• Journal of the Korean Society of School Health
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• v.17 no.1
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• pp.55-69
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• 2004

Purpose ： To describe epidemiological characteristics and related factors in school personnel with hypertension. Method ： 5,384 school personnel (2,638 males and 2,746 females) received physical examination at the Seoul School Health Center in 2002. blood pressure(BP) was classified by JNC 7th report. Normal BP is systolic BP <120 and diastolic BP<80, prehypertension BP is 120-139 or 80-89mmHg, stage 1 hypertension BP is 140-159 or 90-99, and stage 2 hypertension >=160 or >=100 mmHg. each group was evaluated by gender. We used multiple regression and logistic regression. Results ： Normotension was 20.13% in males and 48.65% in female, prehypertension 43.4% in males and 38.06% in females, stage 1 hypertension 26.38% in males and 10.99% in females, stage2 hypertension 9.59% in males and 3.2% in females. the older age group had higher distribution of stage 1 hypertension and stage 2 hypertension. The means and abnormal rates of BMI, blood sugar, total cholesterol, GOT, GPT, and GTP was higher when their blood pressure was higher. However, an alcohol habit among lifestyle factors had an inverse effect. Higher Bp was correlated to a higher BMI, FBS, and cholesterol-like dose response. In stage 1 hypertension, the related factors of hypertension for males were BMI, amount of cigarettes smoked, exercise, blood sugar, total cholesterol, and GTP. In stage 1 hypertension, age, BMI, exercise, blood sugar, total cholesterol were related factors in female. In stage 2 hypertension, age and smoking were related factors in male, and age, BMI, and cholesterol in female. Conclusions ： It is possible to intervene in all related factors of hypertension except age through life-style modification and appropriate medical management. Active health promotion is needed in School personnel.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.7
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• pp.844-853
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• 2014

Since the active sonar for a naval vessel is usually installed in a bulbous bow, GRP(Glass reinforced plastic) material with low density and high strength is used for the material of the sonar dome window in order to prohibit impact by slamming wave or foreign material in the sea. The structural safety of the sonar dome is varied according to the interior and exterior distributed pressure on the sonar dome. Therefore, the variation of the structural safety according to the pressure variation of the sonar dome window caused by the drain valve state is studied by CAE.

• Journal of Sensor Science and Technology
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• v.29 no.5
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• pp.354-359
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• 2020

The high vacuum hermetic sealing technique ensures excellent performance of MEMS resonators. For the high vacuum hermetic sealing, the customization of anodic bonding equipment was conducted for the glass/Si/glass triple-stack anodic bonding process. Figure 1 presents the schematic of the MEMS resonator with triple-stack high-vacuum anodic bonding. The anodic bonding process for vacuum sealing was performed with the chamber pressure lower than 5 × 10^-6 mbar, the piston pressure of 5 kN, and the applied voltage was 1 kV. The process temperature during anodic bonding was 400 ℃. To maintain the vacuum condition of the glass cavity, a getter material, such as a titanium thin film, was deposited. The getter materials was active at the 400 ℃ during the anodic bonding process. To read out the electrical signals from the Si resonator, a vertical feed-through was applied by using through glass via (TGV) which is formed by sandblasting technique of cap glass wafer. The aluminum electrodes was conformally deposited on the via-hole structure of cap glass. The TGV process provides reliable electrical interconnection between Si resonator and aluminum electrodes on the cap glass without leakage or electrical disconnection through the TGV. The fabricated MEMS resonator with proposed vacuum packaging using three-layer anodic bonding process has resonance frequency and quality factor of about 16 kHz and more than 40,000, respectively.

• International Journal of Automotive Technology
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• v.8 no.3
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• pp.269-274
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• 2007

A prior fundamental study was executed using a constant volume chamber (CVC) to improve the burning characteristics of lean pre-mixture by the injection of active radicals generated in the sub-chamber of the CVC. The Radical ignition (RI) technique shows remarkable progress in the burning velocity and combustible lean limit compared with the results of the spark ignition (SI) technique. The optimum design value of the sub-chamber geometry is near $0.11cm^{-1}$ for the ratio of the total area of the holes to the sub-chamber volume $(A_h/V_s)$. In this study, based on the former experimental results, the additional works have been performed to examine the effects of the geometry change in the number $(N_h)$, the total section area $(A_h)$, and diameter $(D_h)$ of the passage holes on the combustion characteristics in the CVC. Also ambient conditions such as the initial temperature and the initial pressure of the mixture were selected as experimental parameters and the effects of residual gas at the chamber on the combustion characteristics were investigated. As a result, the correlation between the passage hole number and overall passage hole area was grasped. The effects of the initial temperature were significant, but on the other hand, those of the initial pressure were weak. A more detailed analysis on the residual gas is required in the future.

• YAKHAK HOEJI
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• v.44 no.6
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• pp.558-565
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• 2000

SK-1080 is one of the newly developed orally active nonpeptide angiotensinII $AT_1-receptor$ antagonist that selectively acts at $AT_1$ receptor with high affinity. The cardiac effect on ischemia/reperfusion injury of SK-1080 was compared with those of losartan, a prototype of this class, in isolated rat hearts. Isolated perfused rat heart was pretreated with drug for 10 min and then subjected to global ischemia for 30 min followed by reperfusion with- or without drug for 30 min. The possible additive effect of SK-1080 on the platelet aggregation and coagulation in human blood was also studied. We investigated whether SK-1080 effects the platelet aggregation induced by ADP, a platelet agonist partially dependent on $thromboxaneA_2$. The clotting times in the prothrombin time (PT) and activated partial thromboplastin time (APTT) were also examined in human plasma in vitro as coagulation screening test. SK-1080 improved reperfusion function (LVDP, left ventricular developed pressure; PRP, rate-pressure product) in a dose-dependent manner. SK-1080 reduced ADP-induced platelet aggregation compared with vehicle but less than losartan, and did not affect clotting times.