• 한국지구과학회지
• /
• 제30권5호
• /
• pp.630-645
• /
• 2009

The tropopause fold event that took place on January 1, 1997 over mid-region on the Korean Peninsula is examined by means of a numerical simulation based on a Mesoscale Model (MM5). The purpose of this paper is to investigate the effects of moisture in reinforcing a tropopause fold linked to an explosive cyclone. Two types of simulations were carried out; 1) simulations for moist conditions in which full physical and dynamic processes are considered and 2) simulations for dry conditions in which cumulus parameterization and cloud microphysics process are excluded. The results of the moist condition simulations demonstrate that the intensity of the central pressure of the cyclone was overestimated compared with the observed values and that the location of the center and the pressure deepening rates (-17 hPa/12 hr) complied with the observed values. The potential vorticity (PV) anomaly on the isentropic surface at 305 K continued to move in a southeast direction on January 1, 1997 and thus created a single tube of tropopause fold covering the northern and the middle area of the Korean Peninsula and reaching the ground surface at 0300 UTC and 0600 UTC. The results of the dry condition simulations show that the tropopause descended to 500 and 670 hPa in 0300 and 0600 UTC, respectively at the same location for the moist condition simulation; however, there was no deep tropopause fold observed. A comparison of the simulated data between the moist and the dry conditions suggests that a deep tropopause fold should happen when there is sufficient moist in the atmosphere and significantly large PV in the lower atmosphere pulls down the upper atmosphere rather than when the tropopause descends itself due to dynamic causes. Thus, it is estimated that moisture in the atmosphere should have played a crucial role in a deep tropopause fold process.

• Journal of Mechanical Science and Technology
• /
• 제15권4호
• /
• pp.492-499
• /
• 2001

The characteristics of Prand시-Meyer expansion of supersonic flow with condensation along a wavy wall in a channel are investigated by means of experiments and numerical analyses. Experiments are carried out for the case of moist air flow in an intermittent indraft supersonic wind tunnel. The flow fields are visualized by a Schlieren system and the distributions of static pressure along the upper wavy wall are measured by a scanning valve system with pressure transducers. In numerical analyses, the distributions of streamlines, Mach lines, iso-pressure lines, and iso-mass fractions of liquid are obtained by the two-dimensional direct marching method of characteristics. The effects of stagnation temperature, absolute humidity, and attack angle of the upper wavy wall on the generation and the locations of generation and reflection of an oblique shock wave are clarified. Futhermore, it is confirmed that the wavy wall plays an important role in the generation of an oblique shock wave and that the effect of condensation on the flow fields is apparent.

• Transactions on Electrical and Electronic Materials
• /
• 제7권5호
• /
• pp.262-266
• /
• 2006

The insulation diagnostic test and the AC breakdown test were performed under off-line using the 3.3 kV class induction motor which have been served for 10 years. These tests were conducted in means of nondestructive and destructive test. In this paper, we compared the correlation between the nondestructive and destructive test. Furthermore we setup an experimental condition with moisture and compared the insulation characteristics between moist and dry sample. From the results of the nondestructive and destructive test, it was found that the second AC current, which is the previous step of insulation breakdown, suddenly increased at a point of around 8.5 kV. The insulation breakdown of moist sample occurred at 12-14 kV, which is 4-5 kV lower than dry sample.

• 한국식품과학회지
• /
• 제52권5호
• /
• pp.503-509
• /
• 2020

The present study investigated the effects of dry and moist heat treatments on total phenols, total anthocyanins, and antioxidant activity levels in black chokeberry (Aronia melanocarpa) fruits. Lyophilized chokeberry powder samples were heated in a drying oven at 60, 100, 160, 180, and 200℃ for 20, 40, or 60 min. Finely ground fresh chokeberry fruits were heated in water at 60, 80, and 100℃ for 20 min, and bioactive compound and antioxidant activity levels were measured. The bioactive compounds and antioxidant activity decreased with increasing temperature and treatment duration. Antioxidant activity was preserved at 160℃ or lower without significant loss for dry heating, whereas moist heat treatment increased both bioactive compounds and antioxidant activity with increasing temperature.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2003년도 추계학술대회
• /
• pp.514-519
• /
• 2003

A computational study is performed to clarify the characteristics of supersonic moist air jet issuing from a simple sonic nozzle. The effects of the initial supersaturation on the Mach disk diameter and location, the barrel shock wave and jet boundary structures are investigated in details. The axisymmetric, compressible, Navier-Stokes equations, coupled with droplet growth equation, are solved using a third-order MUSCL type TVD finite-difference scheme. It is found that the Mach disk diameter increases with an increase in relative humidity of moist air. while its location is not significantly dependent on the relative humidity. As the relative humidity increases, the barrel shock wave and jet boundary are more expanded due to the local static pressure rise of nonequilibrium condensation.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2003년도 추계학술대회
• /
• pp.562-567
• /
• 2003

A computational study is performed to clarify the characteristics of supersonic moist air jet issuing from a simple sonic nozzle. The effects of the initial supersaturation on the Mach disk diameter and location, the barrel shock wave and jet boundary structures are investigated in details. The axisymmetric, compressible, Navier-Stokes equations, coupled with droplet growth equation, are solved using a third-order MUSCL type TVD finite-difference scheme. It is found that the Mach disk diameter increases with an increase in relative humidity of moist air. while its location is not significantly dependent on the relative humidity. As the relative humidity increases, the barrel shock wave and jet boundary are more expanded due to the local static pressure rise of nonequilibrium condensation.

• Mycobiology
• /
• 제46권3호
• /
• pp.215-223
• /
• 2018

In this study, we examined myxomycetes that developed in moist chamber cultures of substrata material collected from $K{\ddot{u}}tahya$ and Konya provinces in Turkey. We collected bark samples from living trees, plant litter from the ground, standing dead wood or stumps, and downed and decayed wood or bark and placed them in the moist chamber cultures. We identified 36 species belonging to 12 genera of myxomycetes. The species determined are listed, and four new records, Didymium balearicum Ing, Macbrideola oblonga Pando & Lado, Paradiacheopsis erythropodia (Ing) Nann-Bremek. and Perichaena pedata (Lister & G. Lister) G. Lister, are added to the mycoflora of Turkey.

• Journal of Oral Medicine and Pain
• /
• 제30권4호
• /
• pp.401-410
• /
• 2005

본 연구는 온열요법이 표층부 혈류량과 피부 온도에 미치는 영향을 평가하기 위해, 건강한 성인 20명(남성: 10명, 여성: 10명)을 대상으로 습열요법과 초음파요법 적용전후의 전이부 표층부 혈류량과 피부 온도를 각각 laser doppler flowmetry와 접촉식온도계를 사용하여 측정함으로써 다음과 같은 결론을 얻었다. 1. 습열요법과 초음파요법 모두에서, 표층부 혈류량과 피부 온도는 적용전보다 적용후에 유의하게 증가하였다. 2. 습열요법을 시행한 경우, 초음파요법에 비해 적용직후 표층부 혈류량과 피부 온도의 증가량이 유의하게 더 컸으며, 증가된 상태도 더 오래 유지되었다. 3. 온열요법 적용전 표층부 혈류량과 피부 온도는 남성이 여성에 비해 더 높았다. 4. 온열요법 적용전후 표층부 혈류량과 피부 온도의 변화량은 남녀간의 유의한 차이가 없었다.

• 대한간호
• /
• 제6권4호통권30호
• /
• pp.67-71
• /
• 1967

• 펄프종이기술
• /
• 제45권5호
• /
• pp.49-55
• /
• 2013

To explore the paper materials for restoration of the Annals of the Joseon Dyansty, durability of the three type of the traditional Korean Papers were estimated in this study, through moist heat artificial aging test. Three types(D, F, and G) which showed the best preservation performance in dry heat and UV treatment in the previous study were selected and artificial accelerated aging treatment with moist-heat process was conducted; the viscosity change rate was D>G>F; folding endurance G>D>F; $L^*$ value F>D>G; $a^*$ and $b^*$ change rate D>G>F; brightness decrease rate D>G>F, suggesting paper F showed the least change rate in physical/optical properties. Also the CLSM image observation showed fair coherence among fibers and confirmed paper mulberry. And in FDI extraction from each sample, paper F showed the highest value. Overall, paper F (traditional glossy paper) showed the highest stability against thermal treatment. It confirms that paper F is suitable as restoration paper for tributary remains including the annals of the Joseon Dynasty for its steady strength/viscosity decrease rate and color change rate.