• Food Science and Preservation
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• v.14 no.1
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• pp.109-112
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• 2007

Precooling and improved packing of mushrooms were investigated with a view to prolonging their freshness. Harvested mushrooms were precooled by forced air cooling and then packed in an EPS container. Mushrooms were transported to customers by insulated truck and stored at either $10^{\circ}C\;or\;25^{\circ}C$. Conventionally packed mushrooms in cartons were also examined as controls. Mushroom respiration rate slowly fell 2- to 3-fold upon precooling. Weight loss was decreased by precooling and the use of the insulated pack. Also, the L-value of the mushroom surface remained high with precooling, and mushroom elongation was less than in the control. Summer market life was extended to 3-4 days (from 1-2 days) by the improved distribution method.

• Atmosphere
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• v.23 no.4
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• pp.377-387
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• 2013

Projections of changes in the low latitude atmospheric circulation under global warming are investigated using the results of the CMIP5 ensemble mean. For this purpose, 30-yr periods for the present day (1971~2000) and the end of the $21^{st}$ century (2071~2100) according to the RCP emission scenarios are compared. The wintertime subtropical jet is projected to strengthen on the upper side of the jet due to increase in meridional temperature gradient induced by warming in the tropical upper-troposphere and cooling in the stratosphere except for the RCP2.6. It is also found that a strengthening of the upper side of the wintertime subtropical jet in the RCP2.6 due to tropical upper-tropospheric warmings. Model-based projection shows a weakening of the mean intensity of the Hadley cell, an upward shift of cell, and poleward shift of the Hadley circulation for the winter cell in both hemispheres. A weakening of the Walker circulation, which is one of the most robust atmospheric responses to global warming, is also projected. These results are consistent with findings in the previous studies based on CMIP3 data sets. A weakening of the Walker circulation is accompanied with decrease (increase) in precipitation over the Indo-Pacific warm pool region (the equatorial central and east Pacific). In addition, model simulation shows a decrease in precipitation over subtropical regions where the descending branch of the winter Hadley cell in both hemispheres is strengthened.

• Nuclear Engineering and Technology
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• v.20 no.1
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• pp.27-34
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• 1988

Since the lack of the spent fuel storage capcity has been expected for all Korean nuclear power plants in the mid-1990s, the maximum density rack (MDR) with consolidated fuels can be proposed to overcome the shortage of the storage capacity in KNU 9 & 10 which have most limited capacities. To ensure the safety when the alternatives are applied in the KNU 9 & 10, the multiplication factor are calculated with varying the rack pitch and the thickness of consolidated storage box by the AMPX-KENO IV codes. The computing system is verified by the benchmark calculation with criticality experiments for arrays of consolidated fuel modules, which was reported by B & W in 1981. Also an abnormal condition, i.e. malposition accident, is simulated. The results indicate that the KNU 9 & 10 storage pools with consolidated fuel are safe in the view of the criticality. Thus the storage capacity can be expanded from 9/3 cores into 27/3 cores even with considering equipments and cooling spaces.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.10
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• pp.134-147
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• 2001

Laser cladding process accompanies phase transformations from melting (on heating) through solidifying (on cooling) at the same time within a small material volume and to final solid phase. The phase transformations are not reversible, but an irreversible thermodynamic process; they accompany either absorption or release of thermal energy (referred to latent heat) during transformation. Yet, most analyses on materials processed by laser as a heat source have been performed on models of neglecting the latent heat in the process and those did not Justify the simplification. With literatures on the laser material process, we have not place an answer to how little the assumption affects on analyses. This led us to our current study: the effects of latent heat on thermo-mechanical analysis. To this end, we developed a fairly accurate program accommodating an algorithm for enforcing the latent heat whenever necessary and ran it combining with ABAQUS$^{TM}$. The simulation techniques we used in this study were verified by directly comparing our prediction with experimental publications elsewhere; our numerical results agreed accurately with the experiments. On the effects of the latent heat, we performed two alternatives about considering the latent heat in analysis, and compared each other. As a result, we found that more accurate conclusions might come out when considering the latent heat in process analyses.s.

• Proceedings of the Korean Quaternary Association Conference
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• 2004.11a
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• pp.37-43
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• 2004

The response of the CCCma coupled climate model to the imposition of LGM conditions is investigated. The global mean SAT and SST decrease by about $10^{\circ}C$ and $5.6^{\circ}C$ in the coupled model. Tropical SST decreases by $6.5^{\circ}C$, whereas CLIMAP reconstructions suggest that the tropics cool by only about $1.7^{\circ}C$, although the larger tropical cooling is consistent with the more recent proxy estimates. With the incorporation of a full ocean component, the coupled model gives a realistic spatial SST pattern, capturing features associated with ocean dynamics that are seen in the CLIMAP reconstructions. The larger decrease of the surface temperature in the model is associated with a reduction in global precipitation rate (about 15%). The tropical Pacific warm pool retreats to the west and a mean La $Ni\tilde{n}a$-like response is simulated with less precipitation over the central Pacific and more in the western tropical Pacific. The more arid ocean climate in the LGM results in an increase in SSS almost everywhere. This is particularly the case in the Arctic Ocean where large SSS increase is due to a decrease in river discharge to the Arctic Ocean associated with the accumulation of snow over the ice sheet, but in the North Atlantic by contrast SSS decreases markedly. This remarkable reduction of SSS in the North Atlantic is attributed to an increase in fresh water supply by an increase in discharges from the Mississippi and Amazon rivers and an increase in P-E over the North Atlantic ocean itself. The discharges increase in association with the wetter LGM climate south of the Laurentide ice sheet and in South America. The fresh water capping of the northern North Atlantic results in a marked reduction of deep convection and consequently a marked weakening of the North Atlantic overturning circulation. In the LGM, the maximum overturning stream function associated with the NADW formation decreases by about 60% relative to the control run, while in the Southern Ocean, oceanic convection is stronger in the LGM due to reduced stratification associated with an increase in SSS and a decrease in SST and the overturning stream function associated with the formation of AABW and the outflow increases substantially.

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.3
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• pp.133-140
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• 2002

Site-specific minimum temperature forecasts are critical in a short-term decision making procedure for preventive measures as well as a long-term strategy such as site selection in fruits industry. Nocturnal cold air pools frequently termed in mountainous areas under anticyclonic systems are very dangerous to the flowering buds in spring over Korea, but the spatial resolution to detect them exceeds the current weather forecast scale. To supplement the insufficient spatial resolution of official forecasts, we developed a GIS - assisted frost risk assesment scheme for using in mountainous areas. Daily minimum temperature data were obtained from 6 sites located in a 2.1 by 2.1 km area with complex topography near the southern edge of Sobaek mountains during radiative cooling nights in spring 2001. A digital elevation model with a 10 m spatial resolution was prepared for the entire study area and the cold air inflow was simulated for each grid cell by counting the number of surrounding cells coming into the processing cell. Primitive temperature surfaces were prepared for the corresponding dates by interpolating the Korea Meteorological Administration's automated observational data with the lapse rate correction. The cell temperature values corresponding to the 6 observation sites were extracted from the primitive temperature surface, and subtracted from the observed values to obtain the estimation error. The errors were regressed to the flow accumulation at the corresponding cells, delineating a statistically significant relationship. When we applied this relationship to the primitive temperature surfaces of frost nights during April 2002, there was a good agreement with the observations, showing a feasibility of site-specific frost warning system development in mountainous areas.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.11a
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• pp.104-104
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• 2018

Kori Unit 1 is the first permanent shutdown nuclear power plant in Korea and it is on June 18th, 2017. Spent fuel assemblies began to be discharged from the reactor core to the spent fuel pool(SFP) within one week after shutdown of Kori unit 1 and the campaign was completed on June 27th, 2017. The total number of spent nuclear fuel assemblies in SFP of Kori Unit-1 is 485 and their discharging date is different respectively. So, decay heat was evaluated considering the actual enrichment, operation history and cooling time of the spent fuel assemblies stored in SFP of the Kori Unit-1. The code used in the evaluation is the ORIGEN-based CAREPOOL system developed by KHNP. Decay heat calculation of PWR fuel is based on ANSI/ANS 5.1-2005, "Decay heat power in light water reactors" and ISO-10645, "Nuclear energy - Light water reactors - Calculation of the decay heat power in nuclear fuels. Also, we considered the contribution of fission products, actinide nuclides, neutron capture and radioactive material in decay heat calculation. CAREPOOL system calculates the individual and total decay heat of all of the spent fuel assemblies in SFP of Kori Unit-1. As a result, the total decay heat generated in SFP on June 28th, 2017 when the spent fuel assemblies were discharged from the reactor core, is estimated to be about 4,185.8 kw and to be about 609.5 kw on September 1st, 2018. It was also estimated that 119.6 kw is generated in 2050 when it is 32 years after the permanent shutdown. Figure 1 shows the trend of total decay heat in SFP of Kori Unit-1.

• Journal of Korean Public Health Nursing
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• v.13 no.2
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• pp.101-114
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• 1999

This study was designed to investigate the effects of an aquatic exercise program on the shoulder joint function. physical symptom. quality of life and stress among the patients who received modified radical mastectomy between 6 to 12 months prior to their visits. The subjects were 31 women aged between 40 and 60 who visited the out-patient department at Kang Nam St. Mary's Hospital for follow-up care. and were not under the treatment of intravenous cancer chemotherapy or radiation therapy. and had no complications. Twelve of them were assigned to the control group. while nineteen subjects to the experimental group. The aquatic exercise program was developed by the author with the assistance of exercise specialists. The program includes warming uP. aerobic and cooling down exercises in water. The aquatic exercise program for the experimental group was carried out 3 times a week with 60 minutes in each time for 8 weeks from September 20th to November 15th. 1995 in a regular swimming pool in Seoul. Changes in the range of motion of the shoulder joint. muscle strength. physical symptom. quality of life. and stress were examined after the completion of treatment. The data were collected through isokinetic muscle strength evaluation and questionnaire survey before and after the treatment. Paired and unpaired t-test were adopted to analyze the data. The results were as follows ; 1. The increment in the range of motion of the shoulder joint in the experimental group after the exercise was significantly greater than those in the control group. 2. The peak torque of shoulder girdle muscles increased significantly after the exercise in the experimental group only. 3. The physical symptom score decreased significantly after the exercise in the experimental group only. 4. The experimental group revealed significantly higher level of quality of life and lower level of stress after the exercise compared with those before the exercise. whereas the control group showed no significant changes in those levels. These findings may indicate that the aquatic exercise program is effective in increasing the range of motion of the shoulder joint and muscle strength and quality of life. and also effective in decreasing physical symptoms. and the level of stress in postmastectomy patients. Accordingly. the acquatic exercise program' can be adopted as an effective nursing intervention for postmastectomy rehabilitation.

• Restorative Dentistry and Endodontics
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• v.17 no.1
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• pp.10-21
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• 1992

The purpose of this study was to investigate the analgesic effect of eugenol, capsaicin and demethoxy-NE. Young adult cats, weighing 2.0 to 3.0kg, were used. Each animal was anesthetized (${\alpha}$-chloralose 60mg per kg body weight) and divided into four groups; control, eugenol, capsaicin and demethoxy-NE group. The anterior digastric muscles were exposed and a pair of electrodes was inserted to record the electromyograms. To expose the pulp, each canine teeth was prepared with a low speed bur under cooling and used for recording anterior digastric muscular EMGs evoked by noxious stimulation of dental pulp. To observe effects on jaw opening reflex, inferior alveolar nerve of both sides were exposed for drug application and wire electrodes were inserted in anterior digstric muscle for recording the EMGs. To observe effects on action potential, saphenous nerves of both sides were exposed and three tissue pools were made from surrounding tissue. The most distal pool was used for applying stimulation, the most proximal one for recording of action potential, and the other one for drug application. One side of inferior alveolar nerve and saphenous nerve were used for eugenol, capsaicin, or demethoxy-NE application, the other side of nerve for control experiments(only vehicle application). Anterior digastric muscular EMGs evoked by noxious stimulation of dental pulp were recorded before drug application, immediate after drug application, at 60 and 120 minutes, and 5 days after drug application. Action potentials were recorded before drug application, immediate after 30 minutes drug application, at 30, 60 and 120 minutes after drug had been washed out. The results were as follows; 1. Eugenol had a continuous blocking effect on the anterior digastric muscular EMGs evoked by noxious pulp stimulation and after 5 days, showed completely blocking effect. 2. After 5 days, demethoxy-NE applied to dental pulp had a considerable blocking effect on the jaw opening retlex evoked by noxious stimulation but capsaicin had no significant effect. 3. After 5 days, eugenol group showed the strongest blocking effect among the all experimental groups on the jaw opening reflex evoked by noxious stimulation of dental pulp and capsaicin group showed the weakest blocking effect. 4. Eugenol had a completely blocking effect on the action potential conductivity of peripheral nerve. Capsaicin and demethoxy-NE had the blocking effect on the action potential conductivity of ${\alpha}$-and C-nerve fibers. 5. Capsaicin, demethoxy-NE and eugenol applied to inferior alveolar nerve surppressed the jaw opening reflex evoked by noxious stimulation of dental pulp.