• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1580-1581
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• 2008

We investigated the effects of intermittent hydrostatic pressure with various duration of resting period on changes in calcium ($Ca^{2+}$) concentration and adhesive forces of cells on substrates. The quantitive adhesive forces of cells were measured under various resting periods. When the pressure applied to the cells, the concentration of $Ca^{2+}$ increased. Under intermittent hydrostatic pressure, the concentration of $Ca^{2+}$ was maintained under a resting period of 15 min, while it was not decreased with other resting periods of less than 15 min. With a resting period of 15 min, the magnitudes of adhesive forces were significantly increase. In addition, the adhesive forces were measured with and without $Ca^{2+}$ chelating agents to evaluate the effect of $Ca^{2+}$ on cell adhesiveness. When $Ca^{2+}$ ions were chelated, the adhesive forces dramatically decreased, even under intermittent hydrostatic pressure. We conclude that $Ca^{2+}$ plays an crucial role in modulating the adhesive forces of cells, and that the concentration of $Ca^{2+}$ can be increased by intermittent hydrostatic stimuli.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.312-316
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• 2004

Single-well tracer tests, especially push pull tracer tests, are more effective to estimate hydraulic parameters and microbial metabolic activities in terms of duration and cost compared to multi-well tracer tests. However, there are some drawbacks in accuracy, complicated data analysis and uniqueness. These shortages are thought to be derived from the applied conditions which affect mass recovery curve and breakthrough curve. Factors such as extraction rate, resting period, hydraulic conductivity and hydraulic gradient are considered as the major factors determining the mass recovery rate and shape of the breakthrough curve. The results of the sensitivity analysis are summarized as follows: 1) the significant change in concentration of breakthrough curve is obtained when the extraction rate increases. This effect would also be much higher if the hydraulic conductivity is lower; 2) the mass recovery rate decreases with the increase of resting time, and the difference of mass recovery rates for different resting times is inversely proportional to the hydraulic conductivity; 3) the sensitivity values decrease with time. The hydraulic conductivity affects not only the early period, but the later period of the breakthrough curves; 4) The influence of the hydraulic gradient on the breakthrough curves is greater at earlier stage than at later stage. The mass recovery rate is inversely proportional to the hydraulic gradient.

• Korean Journal of Exercise Nutrition
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• v.16 no.2
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• pp.113-122
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• 2012

This study assessed the amount of energy consumed and fat deposition after endurance training in order to review the effect of 4-week endurance exercise on resting metabolic rate of a mouse during and after exercise and the effect of exercise. A total of 19 seven-week-old ICR male mice were used as the study subject. Those mice were divided into sedentary group (Sed) and trained group (Tr) after a week of environment adaption. The Tr group was trained with endurance exercise five times a week for four weeks. Weight and the amount of food intake were daily weighed and resting metabolic rate and metabolic rate after exercise were assessed before starting exercise and on the fourth week after training. Metabolic rate during exercise were measured four weeks after training. At the end of breeding period, statistically significant difference was shown in weights of trained and sedentary groups (p < 0.05). During a resting period, no significant difference was shown in oxygen intake, respiratory exchange ratio, and the amount of carbohydrate and fat oxidized. Moreover, no significant difference was shown in excess post-exercise oxygen consumption (EPOC) of an hour period after training. In contrast, the maximal oxygen uptake (VO₂ max) was approximately 11.1% higher in trained group after training compare to before. However, there was no significant difference in respiratory exchange ratio and carbohydrate and fat oxidization. During exercise, oxygen uptake, carbon dioxide production, and respiratory exchange ratio in energy metabolism during exercise showed no significant difference. However, significant difference was exhibited in the amount of fat oxidized in both groups. Summing up those results, endurance exercise could be concluded to be effective in weight control. However, weight loss is thought to be resulted from increase in fat oxidization during exercise unlike the conclusion made from previous studies where weight loss is prominently influenced by energy metabolism during a resting period and increased fat oxidation during post-exercise recovery. All experimental procedures were carried out at the Animal Experiment Research Center of Konkuk University. This study was conducted in accordance with the ethical guidelines of the Konkuk University Institutional Animal Care and Use Committee.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1215-1220
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• 2004

Cell adhesion to any material surface is considered to be fundamental and important phenomenon in the fields of tissue engineering. Cell adhesion molecules, mechanism, and attachment force have been studied and described a lot. However, the effects of mechanical stimuli on the adhesive forces still have been left much to be investigated. In this study, to investigate the changes in cell adhesive force due to resting time period during the intermittent hydrostatic pressurizing (IHP), cells were cultured under the IHP with various resting times. Then the cell adhesive forces were measured quantitatively utilizing a cell detachment test system and immunofluorescent staining was performed using fluorescent microscopy. In the results, immediately after mechanical stimuli (150 minutes after seeding) and one hour later (210 minutes after seeding), the average adhesive force of experimental group 5 (resting time: 15min) compared with that of control group at same culture time was increased significantly (p<0.05). The results indicated that IHP can contribute in improving cell adhesive force and some of time intervals were required for the expression of cell response.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.4
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• pp.984-993
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• 2016

This study aims to analyze the aquaculture farmers awareness of aquafarm management system influenced by socio-economic, environmental, and other factors using ordered logit model focused on aquafarm resting system. The survey data were obtained from 94 aquaculture farmers in Gyeongsangnamdo and Jeollanamdo province as a cross sectional data in 2015. This paper estimates the impact of socio-economic, environmental, and other characteristics, such as region, working period, productivity, environmental condition of fishing field, expected effectiveness of the system, and subject of responsibility on fishing field management. Based on the result, lastly, it suggests some implications to promote aquaculture farmers perception and participation in aquafarm resting system. The main results are as follows; the aquaculture farmers consciousness of the system is not affected by working period, productivity, and environmental condition of fishing field. But it is influenced by region, expected effectiveness of the system, and subject of responsibility on fishing field management. While it has a positive relationship with expected effectiveness of the system, it has a negative relationship with object who has responsibility on fishing field management.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.5
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• pp.810-823
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• 2020

This study evaluated the effect of functional characteristics of the fabric for Bikram yoga clothing and fit measured in clothing pressure on the wearer's physiological response and perceptive sensation before and after exercise in hot conditions and during a resting period in standard conditions. The test garment consisted of two tops (T1, T2) and two pants (P1, P2) each with different functional characteristics of fabric. Using various combinations of the test garments, assessment of the thermal sensation and comfort was performed before/after yoga and after resting. This study revealed that thermal sensation and wearing comfort significantly changed based on the functionality of the fabric of top garment before the exercise period. In addition, the results showed that based on clothing pressure, the feeling of comfort was different between before yoga and after resting. The appropriate choice of fabric material was important when constructing Bikram yoga clothing worn in hot conditions; however, level of clothing pressure was also found to be an essential design factor for comfort during rest after exercise.

• The Korean Journal of Zoology
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• v.13 no.2
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• pp.51-56
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• 1970

Studies on the feeding and resting behavior of Culex pipiens pallens, a possible vector of Japanese encephalitis in Korea, was carried out at Kobu-Ri, Kobu-Myon, Chongup Kun. Cholla Pukdo in 1967. 1. Indoor and outdoor human biting collections showed that 47.3 per cent Culex pipiens pallens were collected indoors and 52.7 per cent outdoors. 2.Feeding occurred throughout the night from dusk to dawn, with the peak period from 23:00-24:00 hours outside the house and from 24:00-01:00 hours inside. 3. Culex pipiens pallens females preferred man for their blood feeding to domestic animals. The results of human and cow biting collections showed that the feeding ratio between man and cow was 2.1 to 1. As to the feeding preference to the domestic animals, the ratio among cow, pig and horse was 7.3 to 5.1 to 5.4 4. Daytime resting collections showed that large numbers of Culex pipiens pallens females rest inside the house, especially in the bed room and the chicken pen. As temperatures increased, fewer mosquitoes resting indoors and more mosquitoes rest ing outdoors were caught. By means of sweep-net collections at outdoors resting places, a small number of Culex pipiens pallens mosquitoes were caught in such places as grass fields, vegetable fields, barley fields, bean fields, culverts, bomb shelters, and so on. A comparison between number of mosquitoes collected resting during the day in bedrooms and verandahs with resting collections in the same places at night showed that more mosquitoes were present at night. It was observed that the majority of the unfed females rested before feeding at night.

• Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.57-62
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• 2012

Interspecific relationship between a euryhaline rotifer Brachionus rotundiformis and a cyclopoid copepod Apocyclops borneoensis was investigated in the laboratory culture. In a mixed culture of B. rotundiformis and A. borneoensis, population growth of B. rotundiformis was suppressed from day 10, while growth in a monoculture population continuously increased throughout the experimental period. However, the population growth of A. borneoensis in the mixed culture did not markedly differ from that in a monoculture population. Suppression of B. rotundiformis growth coincided with a decrease in the numbers of both non-egg-bearing and egg-bearing females, and increasing resting egg formation. Growth of A. borneoensis was not affected by the presence of the rotifer. However, relative growth index of ovisac bearing females in the mixed culture was 1.62 times higher than that in the monoculture. Presence of the copepod did not greatly reduce the food available to the rotifer population. The rotifer B. rotundiformis responded in a unique way, to stresses such as physical damage (filtering by A. borneoensis) with the production of many resting eggs to increase its chances of survival.

• Journal of Powder Materials
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• v.4 no.2
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• pp.83-89
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• 1997

A finite element analysis to solve the coupled thermomechanical problem in the plane strain upsetting of the porous metals was performed. The analysis was formulated using the yield function advanced by Lee and kim and developed using the thermo-elasto-plastic time integration procedure. The density and temperature dependent thermal and mechanical properties of porous metals were considered. The internal heat generation by the plastic deformation and the changing thermal boundary conditions corresponding to the geometry were incorporated in the program. The distributions of the stress, strain, pressure, density and temperature were predicted during the free resting period, deformation period and dwelling period of the forging process.

• Korean Journal of Community Nutrition
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• v.13 no.5
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• pp.693-700
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• 2008

The purposes this study were to a) analyze the revisiting ratio of resting customers after issuing online coupons, b) compare the characteristics of coupon redemption customers with non-redemption customers. For this study, the customers of M restaurant who did not revisit during the last 8 months were classified as 'resting customers', totaling 4,052 customers. The online coupons, valid for 9 months, were sent via e-mail to those customers. After that, the data collected from those who redeemed the coupon in September 2006 was utilized. As a result of sending the coupon to 4,052 resting customers, 1,288 customers redeemed the coupon during the study period, showing relatively high redemption ratio (31.6%). The average check of customers with the online coupon was decreased by 22% compared with customers without the coupon, but the party size remained almost the same, 2.6 customers, and also the redemption ratio was increasing as the expiration date of the coupon was approaching. The redemption ratio of female (35.3%) was much higher than male (19.2%), representing higher redemption possibility of the female customers by issuing the coupon. The redemption ratio of the twenties (69.1%) was obviously higher than other age groups. Also, the non-redemption ratio of other groups except the twenties was higher than the redemption ratio. The redemption ratio of low-educated was higher, under college degree (58.6%), college degree (35.4%), and over college degree (16.6%). Following the result of the average visiting frequency of redemption customers during last the 8 months was 4.2, the frequency of non-redemption customers was 9.8. The total average visiting of non-redemption customer was 10.5, and that of redemption customers was 8.6. Customers who visited the restaurant less frequently in the past have higher possibility to revisit after receiving the coupon.