• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.6
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• pp.685-695
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• 2019

To assess the state of Todarodes pacificus fisheries, we examined changes in major fishing and ecological characteristics by comparing jigging fishery data between high (HCLP, 1996-2000) and low (LCLP, 2013-2017) catch level periods. The peak catch occurred in October during the HCLP compared with December during the LCLP. The average catch per unit effort was higher during the HCLP (1.3 tons/jigging vessel) than LCLP (1.0 ton/jigging vessel). During the HCLP, fishing grounds were highly concentrated in the southwestern East Sea and Yamato bank, whereas during the LCLP, the distribution of grounds extended to the South Sea, West Sea, and northern East Sea (near Russian waters) at a low density. Water temperatures in the main fishing ground in the southwestern East Sea were higher at 0, 50, and 100 m depths during the LCLP than HCLP. Meanwhile, the average mantle length of catches decreased from 23.5 cm during the HCLP to 22.21 cm during the LCLP. The mantle length at 50% maturity also decreased between the two periods from 22.06 (HCLP) to 18.77 cm (LCLP). These findings will help guide future management strategies for T. pacificus.

• Geotechnical Engineering
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• v.5 no.4
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• pp.47-60
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• 1989

Soft offshore sediments quite frequently contain undissolved gas, probably methane pro- duced biogenically. The presence of gas bubbles can have a significant effect on the engineering behaviours of the seabed. One of the main difference between saturated and gassy soils is that the undrained response is not incompressible, and without volume change, may be assumed for a fully saturated soil. This paper describes the basic experimental work to further understanding of a gassy soil. The test has been performed for a gassy soil under undrained and drained conditions. It was confirmed that the gas inclusions deformed due to changes in the total stress on the sample and also the pore gas pressure response to change in total stress. but not directly to those in pore water pressure. And the test which applied the repeated load under undrained state also showed the similar behaviour as the simple load.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1225-1234
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• 2023

The intensity of crop water stress caused by moisture deficit is affected by growth and heat conditions. For more accurate detection of crop water stress state using remote sensing techniques, it is necessary to select vegetation indices sensitive to crop response and to understand their changes considering not only soil moisture deficit but also heat conditions. In this study, we measured the MERIS terrestrial chlorophyll index (MTCI) and chlorophyll/carotenoid index (CCI) under drought and heat wave conditions. The MTCI, sensitive to chlorophyll concentration, sensitively decreased on non-irrigation conditions and the degree was larger with heat waves. On the other hand, the CCI, correlated with photosynthesis efficiency, showed less sensitivity to water deficit but had decreased significantly with heat waves. After re-irrigation, the MTCI was increased than before damage and CCI became more sensitive to heat stress. These results are expected to contribute to evaluating the intensity of crop water stress through remote sensing techniques.

• YAKHAK HOEJI
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• v.41 no.4
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• pp.498-511
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• 1997

The effects of UK 14,304, an ${\alpha}_2$-adrenergic agonist, on renal function were investigated in dogs. UK 14,304, when given intravenousely($15.0{\mu}g/kg,\;50{\mu}g/kg$), produced the increase of urine flow accompanied with the marked augmentation of free water clearance ($C_{H_2O}$) and reabsorption rates of sodium in renal tubules ($R_{Na}$), and the remarkable decrease of osmolar clearance ($C_{osm}$) and the amounts of sodium excreted in urine ($E_{Na}$). UK 14,304 given into a renal artery($1.5{\mu}g/kg,\;5.0{\mu}g/kg$) elicited the increase of urine flow with the augmentation of $C_{H_2O}$ in both kidney. UK 14,304, when administered into carotid artery($3.0{\mu}g/kg,\;10.0{\mu}g/kg$). exhibited the same aspect as shown in intravenous UK 14.304 at smaller dose than the intravenous dose. Diuretic action of intravenous UK 14,304 were produced together with increase of $C_{H_2O}$ in situation of water diuresis too, changes of renal function in this state were the increase of $C_{osm},\;E_{Na},\;and\;E_K$ (excreted amounts of potassium in urine), and the decrease of $R_{Na}\;and\;R_K$, these were different appearances from situation of saline diuresis. Diuretic action of intravenous UK 14,304 were blocked completely by post or pretreatment of yohim-bine, ${\alpha}_2$-adrenergic blocking agents, and inhibited by pretreatment of vasopressin, antidiuretic hormone. Above results suggest that UK 14,304 produces the diuretic action by the inhibition of vasopressin secretion and suppression of electrolytes reabsorption of electrolytes in renal tubules mediated with central ${\alpha}_2$-adrenoceptor in dog.

• Journal of the Korean Electrochemical Society
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• v.10 no.3
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• pp.196-202
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• 2007

The performance characteristics of the polymer electrolyte fuel cells (PEFCS) were investigated under various humidification conditions at steady-state and transient conditions. The PEFC studied in this study was characterized by I-V curves in the potentiostatic mode and EIS (electrochemical impedance spectroscopy). The I-V curves representing steady-state performance were obtained from OCV to 0.25 V, and the dynamic performance responses were obtained at some voltages. The effects of anodic external humidification were measured by varying relative humidity of hydrogen from 20% to 100% while dry air was supplied in the cathode. At the high voltage region, the performance became higher with the increase of the temperature, while at the low voltage region, the performance decreased with the increase of temperature. The EIS showed that ohmic losses were larger at the dry condition of membrane and the effects of mass transport losses increased remarkably when the external and self-humidification were high. The dynamic responses were also monitored by changing the voltage of the PEFC instantly. As the temperature increased, the current reached steady-state earlier. The self-humidification with the generated water delayed the stabilization of the current except for low voltage conditions.

• Journal of Convergence Korean Medicine
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• v.4 no.1
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• pp.19-27
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• 2022

Objectives: TSepsis and subsequent acute lung injury (ALI) is a critical state of health caused by infection or endotoxins. This study was conducted to evaluate the effect of Water Extract of Aconiti Lateralis Preparata Radix (AR) on lipopolysaccharide (LPS)-induced sepsis in C57BL/6 mice. Methods: Male C57BL/6 mice were intraperitoneally injected with LPS to induce sepsis and ALI. AR was orally fed twice at 30 min and 180 min after LPS injection. At 24 h post injection, mice were sacrificed, bronchoalveolar lavage fluid (BALF) and blood was collected, and lung tissue was harvested. Hematoxylin and eosin staining was performed in lung tissues, wet/dry ratio of the lung tissue was measured, and the serum cytokine and chemokine levels were analyzed. Results: AR revoked the LPS-induced pathological changes in lung tissues, such as abnormal histological structures, immune cell infiltration and lung edema. Also, AR suppressed the neutrophil infiltration into the lung which was greatly increased by LPS injection based on the cell content of collected BALF. Serum cytokines and chemokines were measured, and AR reversed the LPS-induced increase of cytokines such as interleukin 1 beta, interleukin 6, tumor necrosis factor alpha and chemokines including C-X-C motif chemokine ligand 1 and 2. Conclusion: TAR showed a protective effect in the pathological progress of LPS-induced ALI. Especially, AR suppressed lung edema and infiltration of neutrophils by inhibiting cytokine and chemokine expressions. Such results demonstrate the potential of AR as a therapeutic agent for sepsis and sepsis-induced ALI.

• Journal of Korean Society of Disaster and Security
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• v.11 no.2
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• pp.83-89
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• 2018

The significant sedimentation at the estuary in the eastern coast of Korea frequently causes river mouth occlusion where disconnection between the river and sea is observed. River mouth occlusion causing watershed retention raises the environmental risk of the area as it impairs water quality and threatens the area's safety in the event of floods. This study proposes a plan to maintain stability of river channel and flow of flood discharge at the estuary with loss of its function for disaster prevention. To this end, the study tries to change the location and width of stream path, focusing on the center line of stream near the sand bar of river mouth. This allows to identify a shape of stream path that leads the most stable flow. To review the result, this study uses the SRH-2D, a model for two-dimensional hydraulic analysis, and conduct numeric simulation. The simulation result showed that the most effective plan for maintaining the stable flow of running water without having the area sensitive to changes in hydraulic characteristics is to lower the overall river bed height of the sand bar near the center line of stream to a equal level.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.12
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• pp.1018-1022
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• 2011

Nowadays, with improvement of economical income and life qualities, life pattern changes have been brought such as increasing of avocational activities. Consequently, following those life trends, utilization of car is getting increased. Thus, the perceptions of car have been changed from the only means of transport in the past to a 2nd residental space. that is why the car's endo environmental factors are getting so important. Air conditioner regulating air ventilization in vehicle's indoor automatically sets the right temperature based on the differences of indoor and outdoor's temperature with development of advanced functions to provide better environmental qualities in vehicle. However, even those advanced techniques for functional development are got so diverse though, the essential technique for preventing the growth of bateria and mold inside of the air conditioner are not even severals. Especially, evaporator one of the vehicle air conditioning equipments generates cooled air by vaporizing refrigerant in liquid state with the water as the adduct for this reactions. It has structural difficulties for water vaporation then cause the growth of germs. That's why this reseach was focused on the way of eliminating germs in the vehicle air conditioner efficiently. Direct air sterilizer by using UVC(Ultraviolet C) is manufactured and that performances are evaluated.

• Transactions on Electrical and Electronic Materials
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• v.13 no.6
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• pp.273-277
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• 2012

The vacuum drying process for drying of paper in current transformers was modeled with an aim to develop an understanding of the drying mechanism involved and also to predict the water collection rates. A molecular as well as macroscopic approach was adopted for the prediction of drying rate. Ficks law of diffusion was adopted for the prediction of drying rates at macroscopic levels. A steady state and dynamic mass transfer simulation was performed. The bulk diffusion coefficient was calculated using weight loss experiments. The accuracy of the solution was a strong function of the relation developed to determine the equilibrium moisture content. The actually observed diffusion constant was also important to predict the plant water removal rate. Thermo gravimetric studies helped in calculating the diffusion constant. In addition, simulation studies revealed the formation of perpetual moisture traps (loops) inside the CT. These loops can only be broken by changing the temperature or pressure of the system. The change in temperature or pressure changes the kinetic or potential energy of the effusing vapor resulting in breaking of the loop. The cycle was developed based on this mechanism. Additionally, simulation studies also revealed that the actual mechanism of moisture diffusion in CT's is by surface jumps initiated by surface diffusion balanced against the surrounding pressure. Every subsequent step in the cycle was to break such loops. The effect of change in drying time on the electrical properties of the insulation was also assessed. The measurement of capacitance at the rated voltage and one third of the rated voltage demonstrated that the capacitance change is within the acceptance limit. Hence, the new cycle does not affect the electrical performance of the CT.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.575-581
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• 2013

We examined the effect of starvation on the occurrence of tunic softness to determine the cause of mass mortality of cultured Halocynthia roretzi (Drasche) in the Tongyeong region, Korea. In terms of the survival rate of H. roretzi and the occurrence rate of tunic softness, H. roretzi starved for 35 days at water temperatures of 8, 12, and $15^{\circ}C{\pm}0.5^{\circ}C$ (room temperature of $15^{\circ}C{\pm}1^{\circ}C$) did not exhibit tunic softness at water temperatures of either $8^{\circ}C$ or $12^{\circ}C$. for morphological changes, although the tunic of H. roretzi was shrunken and became visibly smaller with a darkening color in all experimental groups, as compared to the state prior to starvation, its tunics bulbs continuously. The ratio of RNA/DNA concentrations and protein contents for each of the tunic sections were lower in the starved group. Our results indicate that tunic softness is not related to feeding deficiency, as no histopathological symptoms were apparent in the digestive gland or tunic of H. roretzi due to starvation.