• The Journal of Korean Academy of Prosthodontics
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• v.44 no.6
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• pp.699-711
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• 2006

Statement of problem. Elastomeric impression materials have been widely used to obtain an accurate impression. However there have not been enough studies on the influence of the thickness of the tray adhesives on the bonding strength between the trays and the elastomeric impression materials. Purpose. In order to understand the relationship between the thickness of the tray adhesive and the tensile bond strength and to suggest the thickness at which the bonding strength is strongest, tensile bond strength related to the thickness of adhesives of 3 different elastomeric impression materials were tested. Materials and methods. 3 impression materials, $Permlastic^{(R)}$. Regular Set(Kerr Corp., Romulus, Michigan, U.S.A.), $Impregum^{TM}$ $Penta^{TM}$(3M ESPE, Seefeld, Germany), and Aquasil Ultra Monophase Regular Set Smart Wetting.(Dentsply Caulk, Milford, Delaware, U.S.A.), were used in this study, and tray adhesives from the same manufacturers of the impression materials were used, which were Rubber Base Adhesive, Polyether Adhesive, and Silfix, respectively. The tray specimens were prepared by autopolymerizing the tray material(Instant Tray Mix, Lang, Wheeling, Illinois, U.S.A.), and a PVC pipe was used to house the impression material. In group A, tray adhesives were applied in multiple thin layers of 1 to 5 and in group B, adhesives were applied only once, in the thickness equivalent to several applications. Lightness($L^*$) of the adhesion surface was measured with a spectrophotometer(CM-3500d, Konica Minolta, Sakai, Osaka, Japan). The tensile bond strength of the elastomeric impression material and the tray resin was measured with universal materials testing machines(Instron, Model 3366, Instron Corp, Nowood, Massachusetts, U.S.A.). A formula between the number of adhesive application layers and the lightness of the adhesion surface was deduced in group A, and the number of adhesive layers in group B was estimated by applying the lightness($L^*$) to the deduced formula. Results. 1. In group A, a statistically significant increase in tensile bond strength appeared when the number of application layers increased from 1 to 2 and from 4 to 5, and no significant difference was present between 2, 3, and 4 layers in Permlastic. In Impregum, the tensile bond strength was significantly increased when the number of adhesive layers increased from 1 to 3, but no significant difference after 3 layers. In Aquasil, the tensile bond strength significantly increased as the number of application layers increased up to 4 but showed no significant difference between 4 and 5. 2. In group B, the tensile bond strength was decreased when the thickness of the adhesive increased in Permlastic. Impregum showed an increased tensile bond strength when the thickness of the adhesive was increased. In Aquasil, the tensile bond strength increased as the number of adhesive application layers increased up to approximately 2.5 layers but it sharply decreased after approximately 4.5. Conclusion. From the study, the common idea that it is better to apply a thin and single coat of tray adhesive needs correction in more detailed ways, and instructions on some of the tray adhesives should be reconsidered since there were several cases in which the tensile bond strength increased according to the increase in the thickness of the adhesives.

• Journal of Korean Academy of Nursing
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• v.5 no.2
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• pp.74-91
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• 1975

A purpose of this study was to compare the breast massage and manual expression of the breast before engagement after delivery with the time of engagement, the throbbing pain in breast, the first amount of breast milk and involution of the uterus. The subjects selected for this study were 138 women (experimental group;69, control group :69) who were admitted to the Dept. of Obtest. and Gyneco. of Kyung Hee University Hospital from Jan. 5 to June 5, 1975. The results of study were as follows; 1 The average age of the women 26.9 years old in the experimental group and 27.6 years old in the control group. As to religion, the number of those who had no religion was 58.0 percent and 62.4 percent respectively. Classified according to occupation, there were 87.0 percent in house wives of the booths group. Educational background; 87.0 percent of high school graduates or above, 78.3 percent respectively. The occupation of husband 53.7 percent of company employees stood highest and 42.0 percent respectively. In according to the grade of wards, 55.1 percent and 52.2 percent of four-men room stood highest. 2. Physical condition: Body weight before this Pregnancy(T=0.4962, N.S.), the size of breast(X²df2 = 0.1728, N.S.), the shape of nipple(X²df3 =1.3804, N.S.), hemoglobin's level of the first day after delivery(T=1.2572, N.S.), the above were showed non significant between the experimental group and control group The investigator found any difference between the two groups of the health condition during the pregnancy, 3. The rate of no experience of breast massage during pregnancy was 85 percent and 75.4 percent (X²df1=2.2562, N.S.). 4. As to the meal during hospitalization after delivery: The booth of the groups in ordinary food took usually of meyer soup and milk(X²df8=2.5957, N.S.). 5. The relation between the first step of breast massage, second step of the manual expression of breast before engagement after delivery and time of engagement : average time of engagement in the experimental group (2.1 days±0.8) was shortened than the control group (3.3 days±1.2). (T=-6.9045, P< 0.005). It toot less time in the experimental group of primipara(2.2days±0.7) than in the control group (3.1day±1.2) and it also took less time in the experimental group of multipara (2.0 days±0.9) than in the control group (3.5days±1.4). (Primipara T=-3.9266, 0< 0.005. Multipara T= 5.2356, P<0.005). 6. The relationship between the first step of the massage and second step of manual expression and the throbbing pain at the time of engagement: The experimental group showed less effect than control group (X²df4= 27.3342 P<0.005). The separate study of primipara and multipara showed remarkable difference in the group of primipara)X²df4=20.7285, p<0.005) and little difference in the multipara group (X²df4=8.8351, p< 0. 10). 7. The relationship between the first step of the breast massage, second stop of the manual expression and first amount of breast milk: The average amount of breast milk increased more conspicuously in the experimental group (33.8㎖±23.4) than in the control(29.8㎖±25.3) (T=0.8262, N.S.). No remarkable difference was found in the respective groups that investigated in the groups of primipara and of multipara. (Primipara T=1.1467, N.S., Multipara T=-0.0354, N.S.). 8. The relationship between the first step of breast massage and second step of manual expression of breast and involution of uterus : Average time needed for uttering involution was sooner in the experimental group of primipasa(-3.3 F.B.±1.1), than the control group of primipara (-2.5F. B.±1.2), and it was sooner in the experimental group of muitipara (-3.0 F. B.±l..3), than the control group of multipara(-2.3 F.B±0.9). Primipara T=-2.9272, p< 0.005, Multipara T=2.5557, p< 0.01).

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.82-90
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• 2007

In an attempt to establish the appropriate ventilation device for the bottle culture of king oyster mushroom (Pleurotus eryngii), we investigated carbon dioxide concentration and fruiting body formation according to the various ventilation systems within the mushroom house. In addition to, the efficiency of air circulation and growth rate as well as the appearance of physiologically abnormal phenotypes during their growth stage were also evaluated. four different ventilation devices, parallel-pressure type, positive-pressure type, negative-pressure type, and positive- and negative-pressure type were applied in this study. The positive-and negative-pressure type showed the highest efficiency of air circulation as $CO_2$ concentration was 800 ppm and the level of air current was relatively low compared to the other types (the $CO_2$ concentration of parallel-pressure type was 1,400 ppm). Moreover, the stipe length, the cap diameter, yield, and general quality grown in positive- and negative type ventilation device were also better than in the other three devices though it took slightly longer period for harvesting (18.4 days) than the others (17.6, 17.9 and 18.3 days). The appearance of physiologically abnormal phenotypes such as fruiting body lump, soft rot, and brown rot were significantly decreased in positive-and negative type compared to other types, while the appearance rates were not much different for other symptoms of bacterial ooze, stipe limb and stipe bumpy. In summary, we propose that the optimal ventilation system for the bottle culture of king oyster mushroom is positive- and negative type, and this device is expected to increase the total quality as well as yield all year around.

• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.406-411
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• 2006

New Guinea impatiens (Impatiens hawkeri) shows very sensitive responses to different light conditions. Due to these phenomena, testers of DUS (distinctness, uniformity and stability) for granting plant variety protection right often have problems distinguishing genetic or physiological differences. New Guinea impatiens 'Fishlimp 149' was grown under several light intensities in a rain-sheltered vinyl house to observe differences of plant growth and flowering. As compared with the control (avg. $1,010{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$), treatments of shade-1 (avg. $599{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and shade-2 (avg. $88{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) showed increased plant height, plant width, leaf size and pedicel length. On the contrary, these growth parameters decreased in shade-3 (avg. $30{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) with the lowest light intensity. Shade-1 treatment enhanced flower characteristics such as flower diameter, upper petal width, side petal width and lower petal length. However, these characteristics were suppressed by lower light intensities than that in shade-1. Anthocyanin contents of shoot, leaf and pedicel decreased with increasing shading, but that of flower petal was the greatest of the shade-1 treatment. Shade-1 treatment showed the greatest Hunter a value analyzed by a colorimeter, and L and b values increased with increasing shading. Shade-1 treatment seemed to be provided the most proper light condition for DUS test of New Guinea impatiens. Additionally, anthocyanin accumulation on New Guinea impatiens during DUS test was due to not genetic differences but physiological phenomenon.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.466-469
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• 2008

A new kidney bean cultivar, "Hwanghyeob 1" was developed at the National Institute of Crop Science in 2005. "Hwanghyeob 1" was selected from a cross between KLG50064 and KLG50073. It has determinate growth habit, white flower, yellow pod color, oval shape of crossed section of pod at the harvesting time for edible pod, white seed coat and middle seed size (21.7 grams per 100 seeds). The average yield of edible pod of "Hwanghyeob 1" was 23.55 M/T per hectare in the yield trials which was carried out at the green house in spring and autumn in 2005. This yield level was 4 percent higher than that of the check cultivar "Kangnangkong 1".

• Korean Journal of Poultry Science
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• v.35 no.2
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• pp.177-182
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• 2008

This studies were conducted to investigate the effect of holding time of broiler at slaughter house on chicken meat quality. Short holding time ($1{\sim}2hrs $) increased chicken meat quality compared to long holding time ($14{\sim}15 hrs$), which resulted in 14% higher grade $1^+$ chicken. In portioned meat, short holding time ($1{\sim}2 hrs$) resulted in 15% higher incidence of grade $1^+$ chicken breast. Also, long holding time occurred higher PSE incidence of chicken breast. pH value of the chicken meat with short holding time was similar to that with long holding time, and that with medium holding time showed the lowest. $L^*$ (lightness) value of the chicken meat was lower with medium holding time than with short holding time, but that in muscle and skin showed increasing tendency with long holding time. Holding time showed no effect on $a^*$ (redness) of the chicken meat, but longer holding time decreased $b^*$ (yellowness) value. This indicated that long holding time adversely affected chicken meat quality.

• Korean Journal of Poultry Science
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• v.40 no.1
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• pp.11-16
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• 2013

Salmonella is closely related with human health of modern society which has concern increased in livestock goods consumption as well as give economic damage throughout the chicken industry such as farm, hatchery, slaughter house and processing plant. From 2007 to 2011, this study investigated Salmonella prevalence from 200 old hen delivery trucks which deliver old egg-laying hens and broiler breeders in Korea. The prevalence of Salmonella species was 38.0% in old hen delivery truck. Serogroup C1 was the most frequently detected serogroup of Salmonella, followed by the serogroups D1, C2 and B. A total of 25 serotypes were identified and Salmonella infantis was the most frequently isolated serotype. In addition, we applied disinfectant to old hen delivery truck for the reduction of Salmonella contamination. The disinfectant consists of formaldehyde, glutaladehyde and quaternary ammonium compound was applied to the trucks. Salmonella isolation rate was significantly decreased after disinfection from 38.0% to 7.5%. Disinfectant could not effectively reduce Salmonella contamination at a dilution of 1:200 which is recommended by manufacturer, but Salmonella isolation rate was significantly decreased at a dilution of 1:50. Since old hen delivery truck could be a potential vector to carry Salmonella into farms and abattoirs, chicken delivery truck should be disinfected thoroughly and sufficiently to control contamination of farms and abattoirs.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.2
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• pp.122-128
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• 2001

In order to find out the effect of nitrogen fertilizers on soil pH, EC, $NO_3-N$ and lettuce growth, this study was conducted by pot experiment in plastic film house condition. The square-pot which was $42{\times}54.5{\times}22cm$ in length, width and height, respectively, was filled with two kinds of soils in different soil EC as $0.20dS\;m^{-1}$ and $1.13dS\;m^{-1}$. Seven kinds of nitrogen fertilizers (urea, potassium nitrate, calcium nitrate, ammonium nitrate, ammonium sulphate, complex fertilizer A(11-10-10) and complex fertilizer B(12-12-12)) were treated in same standard rate of nitrogen for lettuce, transplanted the six lettuce seedlings of 10 days grown per pot, and have been grown for 38~44 days with three times harvesting. Soil pH was increased with the potassium and calcium nitrate treatments and decreased with ammonium nitrate, ammonium sulphate, complex fertilzer A and B, and the pH of urea treatments was kept the same value as the pH of before experiment. The growing status of lettuce seedling were surveyed during the early period after transplanting and withering of seedling was occured in all treatments. The withering rates were 10% in soil of EC $0.20dS\;m^{-1}$ and 44% and 42% in complex fertilizer and ammonium sulphate treaments, respectively, in soil of EC $1.13dS\;m^{-1}$. $NO{_3}^-$ contents of lettuce were about $1,000{\sim}2,000mg\;kg^{-1}$ based on fresh weight and these contents were considered to be lower to compare the $NO{_3}^-$ level of EU countries.

• Journal of Korean Society of Forest Science
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• v.33 no.1
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• pp.1-32
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• 1977

This study has been made to find out more effective way of vegetation establishment on severely denuded forest land from the viewpoint of soil moisture regimes. Various environmental factors were measured to estimate soil moisture conditions of different sites. Soil moisture influence on growth of over vegetations, water requirement and drought resistance were analyzed. The efficiency of water use was also reckoned at different fertility levels and different soil moisture conditions. This research is composed of field experiment and green house experiment. Field experiment includes height growth, survival and coverage analysis of cover vegetations (Robinia pseudoacacia L., Lespedeza bicolor Turcz, Arundinella hirta Tanaka var. ciliare Koidzumi.) with 4 fertility level treatments on 3 slopes (Steep: $37^{\circ}$, Moderate: $25^{\circ}$, Gentle; $17^{\circ}$) during dry season (1 April-30 June) and wet season (1 July-10 September). At the same time temperature, relative humidity and precipitation were measured to understand the environmental changes. Soil moisture conditions were measured with soil moisture meter with 24 soil cells. Green house experiment comprised height, fresh weight and dry weight measurements of cover vegetations with 4 fertility levels and 3 moisture conditions for 70 days. The results extracted from experiments are as follews. 1. Cover vegtations have 3 patterns of water requirement at the early stage of growth. a) Robinia type has high water requirement and weaker drought resistance. b) Lespedeza type has low water requirement and stronger drought resistance. c) Arundinella type has moderate water requirement and weaker drought resistance. 2. The vegetations have different optimum fertility levels in different soil moisture supply condition. a) Robinia needs a low fertility level in dry condition and a high level in wet condition. b) Lespedeza needs only low fertility level in all conditions. c) Arundinella needs a low fertility level in dry condition and a high level in wet condition. 3. The efficiency of water use (Water/1g dry weight) by fertility levels is different from one another. Robinia and Arundinella have a good efficiency at low fertility level in dry condition and at high fertility level in wet condition. Lespedeza has a good efficiency at low fertility level in all conditions. 4. $P_2O_5$ requirement of Robinia and Lespedeza is high, but that of Arundinella is low. Soil moisture condition has a great influence on $P_2O_5$ absorption in dendued forest land. Once Vegetations are established on suitable sites with optimum fertitity level according to different moisture condition, even the small amount of soil water in denuded land can he used with high efficiency and the effect of fertility treatment can be maximized.

• The Journal of Fisheries Business Administration
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• v.4 no.1_2
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• pp.19-57
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• 1973

Laver io one of the most necessary and seasonal items in Korean food from oldtimes. Laver is lagely eaten in dried form, and its supply depends entirely upon culture weeds. The history of laver culture in Korea about sixty or seventy years is older than in Japan. Significance of laver culture is divided into two aspects, one is food supply in the nation, and the other is export to other countries. Houses engaged in laver culture are about foully thousands, and laver production in 1972 is estimated as 1, 3 bitten sheets. (1 sheet is a dried laver of 20 cm sq, in the shape of paper) Especcially meaning of layer production is the concentration of labour input, and systematic management of labour. From around 1920, the method of laver culture was introduced by Japanese Imperialism for mono culture in shallow seas, and mass products of laver is provided to Japan market, DOMESTIC MARKET Fundamental consume function calculates at below, $D_{(68_71)}$=16354 $Y^{0.471}$ $P^{-1.0662}$ where D is total layer demand, Y income variable, P price variable. It means income elasticity is 476. in the whole country, and price elasticity is 1, 07. But generally income elasticity is higher in urban area than in rural area, as shown at 1, 3 in Seoul city. Expence of laver in house expenditure is mutually correlated with another expence, See Table 12 about the relative function. See Table 14 and 16 about the relation between the gathering and the changes of price in auction, wholesale and retail price support system is for two effects, one of which is constraint of the upper price, the other is rise of the lower price. Before the system control, the equation in three year average calculated as below, $Y_{b}$ ＝18, 907.7455＋15435.9364 t (r=0.89) where the origin t＝0 is the November and the units are month. Post the system control, $Y_{p}$ =30, 047.9636+1, 631.1721t (r＝0.97) therefore, this system has an effect only on the rise of lower price, Average annual margins of laver products at four market levels according to the consumer spent is below. EXPORTING MARKET Japanese demand function of laver products is, Log D=5, 289+1, 108 Log Y-1, 395 Log P (r=0.987) where D is Japanese laver demand, Y income variable, P price variable. according to which income elasticity is 1. 1 and price elasticity is 1.4. Laver production in 1970 tile highest record till then, is estimated as six billion sheets. But the recent improvement of laver culture techniques, the production of seeds and freezing storage of seeds has been stabilized. Futher new culture farms have been developed by means of break- water fences or by floating culture method. These improvements have been backed up with increased demand of laver products. Import quantity and price of Korean laver products are restrained by three organizations, that is producer, distributor and consumer. This relationship calculated by regression equation shows that import is influenced only producer organization, at the sacrifice of consumer profit. For increase to export of laver products, we urgently require to open foreign trade of laver products for Japanese consumer, .and Japan has political responsibility to solve Korean laver structure. But with long run timeseries, as regards Japanese production and import quantity, importing function shows increasing trend as below, 250 million sheets ＜3, 947.1674+0.005 $L_{g}$ ＞) 600 million sheets where $L_{q}$ is relative production quantity of laver in Japan. (unit; 100 thousand sheets) Our Export effort should be put on the highly processed products whithin the restraind quote.ote.