• Design & Manufacturing
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• v.14 no.4
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• pp.11-16
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• 2020

In this study, forming of carbon composite parts was performed using an injection/compression molding process. An impregnation of matrix is determined by ability of wet and flow rate between the matrix and reinforcement. The flow rate of matrix passing through the reinforcements is a function of permeability of reinforcement, a viscosity of matrix and pressure gradient on molding, and the viscosity of the matrix depends on the mold temperature, molding pressure and shear strain of matrix. Therefore, compression molding experiment was conducted using a heating mold in order to confirm the possibility of matrix impregnation. The impregnation of the matrix through the porosities between the woven yarns was confirmed by the cross-sectional SEM image of compression molded parts. An injection molding process was also performed at a short cycle time, high molding pressure and low mold temperature than those of compression experiment conditions. Deterioration of impregnation on the surface of molded parts were caused by these injection conditions and it could be the reason of decreasing the maximum tensile strength. In order to improve impregnation of matrix on the surface, injection/compression molding and insert-over molding were applied. As a result of applying injection/compression molding and insert-over molding, it was shown that the improvement of impregnation on the surface and the maximum tensile strength was increased about 2.8 times than the virgin matrix.

• Journal of Korean Academy of Nursing
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• v.41 no.6
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• pp.805-813
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• 2011

Purpose: The purpose of this study was to examine the effectiveness of an interpersonal relationship program on interpersonal relationships, self-esteem, and depression in nursing students. Methods: This was a quasi-experiment with a nonequivalent control group pre-posttest design. Sixty-four nursing students participated in the study with 31 in the experimental group and 33 in the control group. They were from 3 different colleges of nursing located in Seoul. The interpersonal relationship program was held 10 times over 10 weeks, taking 90 minutes per session. The interpersonal relationship change scale developed by Schlein and Guemey, Rosenberg's self-esteem scale, and CED-S for depression were the instruments used in the study. The data collection period was from January 4 to March 8, 2011, and the collected data were analyzed with SPSS 14.0 using the $X^2$-test, t-test, and paired t-test. Results: The results showed a significant difference between the experimental group and the control group in terms of the degree of interpersonal relationships, self-esteem, and depression. Conclusion: The results indicate that interpersonal relationship programs have positive effects for improving interpersonal relationships and self-esteem, and decreasing depression in nursing students.

• Journal of Pharmaceutical Investigation
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• v.33 no.3
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• pp.201-208
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• 2003

Pharmacokinetics and oral bioavailability of levosulpiride was determined in Korean healthy male volunteers. Thirty subjects received a single oral dose (25 mg) of a tablet in a randomized $2{\times}2$ cross-over design. The plasma concentrations of levosulpiride were measured by HPLC and compared with those reported in the literature. Pharmacokinetic parameters for $Isomeric^{\circledR}$ tablet (levosulpiride 25 mg) were revealed as follows: $AUC_{inf}\;737.1{\pm}176.9\;ng{\cdot}hr/ml,\;C_{max}\;56.4{\pm}20.1\;ng/ml,\;T_{max}\;4.2{\pm}1.6\;hr,\;K_a\;1.00{\pm}1.09\;hr^{-1},\;K_{el}\;0.08{\pm}0.02\;hr^{-1},\;and\;t_{1/2}\;8.8{\pm}1.9\;hr$. The rate constant of the absorption phase was obtained based on the first-order kinetics. In the aspect of bioavailability, $Isomeric^{\circledR}$ tablet was bioequivalent to the other product $(Levopride^{\circledR}\;tablet)$ available in the Korea market. Intersubject variations and race differences were show in comparison with the published data in the literature, even though there was a linear relationship between dose ad extent of bioavailability.

• Physical Therapy Korea
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• v.4 no.2
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• pp.1-9
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• 1997

Skeletal muscle fatigue is often associated with diminished athletic performance and inability to maintain an expected force output as a function of time. The purpose of this study was to compare the effect of duration of exercise on skeletal muscle fatigue between Weight Lifters(WL) and Non-Weight Lifters(NWL). There were twelve normal healthy adult volunteers, ranging in age from 18 to 35 years. The group consisted of six NWL and six WL. Randomized cross-over design was set up and work-rest cycle was 8 minutes work and 1 minute rest based on 15% MVC. Muscle fatigue was measured by the amount of force produced by the wrist flexor muscle and EMG amplitude over time. Repeated measures ANOVAs($2{\times}4$) were used to determine two types of subjects(WL, NWL) during four different duration of exercises(16, 32, 48, 64 minutes). The force decreased over time in NWL and WL, but there was no significant difference(F=2.83, p>0.05). However, the EMG amplitude increased in WL(0.8200) and NWL(0.6348). The WL exhibited an increase in EMG at the end of the period, especially at 48 minutes of exercises than did the NWL(F=9.58, p<.05). This suggests the WL were able to adjust to prolonged effort with adaptations in neural effect over time, resulting in higher EMG amplitude. That is, WL may be able to learn to recruit more motor units with training. It is important to the degree of neuromuscular fatigue and the time needed for recovery may differ considerably between WL and NWL, there is a need to plan proper strength training or rehabilitation protocols to match with the requirements in different characteristics of groups.

• Biomolecules & Therapeutics
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• v.16 no.3
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• pp.255-260
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• 2008

The purpose of this study was to evaluate the bioequivalence of the test (Daewoo Hydrocortisone 10 mg, Daewoo Pharm. Co., Busan, Korea) and reference (Jenapharm Hydrocortisone 10 mg, JayTech Biogen, Seoul, Korea) hydrocortisone tablets. Twenty-four healthy male Korean volunteers were divided into two groups with a randomized $2{\times}2$ cross-over design. In order to suppress the endogenous cortisol secretion, a single oral dose of Dexamethasone (4 mg) was administered 10 hr prior to hydrocortisone administration. Blood samples were withdrawn for 10 hr at the predetermined intervals after a single oral dose of hydrocortisone (20 mg). The serum concentration of hydrocortisone was analyzed by HPLC/UV using a column switching method after liquid-liquid extraction process. The pharmacokinetic parameters ($AUC_{0{\sim}10hr}$, $C_{max}$, and $T_{max}$) of the test and reference hydrocortisone tablets were determined while the secretion of endogenous cortisol was being suppressed. The pharmacokinetic parameters of the test tablet were not statistically different from those of the reference tablet at ex value was 0.05. The 90% confidence intervals for the average ratio (test/reference) of $AUC_{0{\sim}10hr}$ and $C_{max}$ were within the Korea Food and Drug Administration acceptance range of 0.80-1.25 ($0.89{\sim}0.99$ and $0.86{\sim}0.99$ for $AUC_{0{\sim}10hr}$ and $C_{max}$, respectively). Therefore it was concluded that the test tablet, Daewoo Hydrocortisone tablet was bioequivalent to the reference tablet, Jenapharm Hydrocortisone tablet.

• Journal of Korean Academy of Nursing
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• v.19 no.1
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• pp.63-80
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• 1989

This study was undertaken at Yonsei University Medical Center to identify the crisis responses and nursing problems of patients who had been diagnosed with cancer, and changing patterns of grieving over time periods, and to analyse the effectiveness of follow up care through home visiting nursing. This study was carried out in three stages. The 1st study data were collected from a total of 205 patients who had been diagnosed with cancer from Sept.1 to Dec. 31, 1987 using a cross-sectional method. The 2nd study data were collected three times from 30 patients with cancer at 4 weeks intervals from March 1 to June 31, 1988 using a longitudinal method. The 3rd study data were collected from two different groups from March 1 to June 31, 1988. One was an experimental group who was visited by nurses and the other one was a control group not visited by nurses. The subjects of the 3rd study consisted of 60 patients with cancer and a Quasi-experimental research design was used. The results were as follows ; 1. The patients did not experience one stage at a time among the five stages of grieing, denial anger, bargaining, depression and acceptance, as identified by Kubler Ross. They experienced a combination of stages, especially of the bargaining and the depression stages. This stages did not change with the passing of time. 2. The patients expressed more physical and socioecounomical problems than emotional problems. And they used more problem coping methods than emotional coping methods. 3. Follow up care through home visiting nursing positively influenced the patient's quality of life, especially their physical well-being and symptom control The patients responded positively to the home visiting nursing, stating that it was helpful In them. It was concluded that the development of a home visiting nursing program is needed for the effective home care of patients with cancer.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.9
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• pp.1389-1396
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• 2007

Twelve swamp buffaloes and Brahman cattle heifers (6 animals each) were randomly assigned to two treatments, control (grazing only) and supplementation of cassava hay (CH) at 1-kg dry matter per head per day (DM/hd/d), in a $2{\times}2$ factorial arrangement according to a cross-over design. The cassava hay contained a high level of protein (19.5% of DM) and a strategic amount of condensed tannins (4.0% of DM). As a result it was revealed that supplementation of CH at 1-kg DM/hd/d significantly (p<0.05) improved the nutrition of both swamp buffaloes and Brahman cattle in terms of DM, organic matter (OM), protein and energy intake and digestibility, ruminal NH3-N and rumen ecology. Supplementation significantly (p<0.05) reduced weight losses in both species and improved the health, in terms of reduced number of parasite eggs in feces (p<0.05), of both buffaloes and cattle. There tended to be a difference in term of response to CH between the two species. The DM, OM, protein intake and digestibility and total digestible energy intake tended to be higher for buffaloes as compared to cattle. Moreover, the percentage reduction of parasite eggs tended to be higher for buffaloes as compared to cattle (57.6 and 45.0%, respectively). However, there were no significant interactions between species and treatments.

• Journal of Pharmaceutical Investigation
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• v.41 no.3
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• pp.191-196
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• 2011

In this study simple and sensitive high performance liquid chromatographic method using a commercially available column, was developed and validated for the determination of zolpidem tartrate in human plasma. The developed method with suitable validation was applied to a bioequivalence study of two different kinds of zolpidem tartrate. Two different formulations containing 10 mg of zolpidem tartate (CAS : 99294-93-6) were compared in 24 healthy male volunteers in order to compare the bioavailability and prove the bioequivalence. The study was performed in an open, single dose randomized, 2-sequence, cross-over design in 24 healthy male volunteers with a one-week washout period. Blood samples for pharmacokinetic profiling were drawn at selected times during 12 h. The mean $AUC_{0-12h}$, $C_{max}$, $T_{max}$ and $T_{1/2}$ were $676.6{\pm}223.4$ $ng{\cdot}h{\cdot}mL^{-1}$, $177.4{\pm}34.2$ $ng{\cdot}mL^{-1}$, and $0.8{\pm}0.4$ and $3.5{\pm}2.1$, respectively, for the test formulations, and $640.7{\pm}186.6$ $ng{\cdot}h{\cdot}mL^{-1}$, $193.0{\pm}64.5$ $ng{\cdot}mL^{-1}$, and $0.9{\pm}0.4$ and $2.7{\pm}0.9$, respectively, for the reference formulation. Both primary target parameters $AUC_{0-12h}$ and $C_{max}$ were log-transformed and tested parametrically by analysis of variance (ANOVA). 90% confidence intervals of $AUC_{0-12h}$ and $C_{max}$ were in the range of acceptable limits of bioequivalence (80-125%). Based on these results, the two formulations of zolpidem tartate are considered to be bioequivalent.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.2
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• pp.216-226
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• 1983

Genetic studies on the $F_2$ generation of a set of half diallel crosses involving six cowpea varieties were conducted. by the randomized block design with three replications to determine combining ability, gene action and the relationships between parents and their $F_2$ hybrids. The 12 agronomic characters namely, days to flowering, days from flowering to maturity, days to maturity, diameter of stem, length of internode, number of branches per plant, length of pod, number of pods per plant, number of grains per pod, number of grains per plant, 100 grain weight and grain weight per plot were observed, and the $F_2$ generation of this diallel set of crosses was analysed for each character according to the method by Jinks and Hayman. The results obtained are summarized as follows: 1. Vr-Wr graphical analyses; The following seven characters, days to flowering, number of branches per plant, length of pod, number of pods per plant, number of grains per plant, 100 grain weight and grain weight per plot appeared to be partially dominant, and over dominance was found for days from flowering to maturity, days to maturity, length of internode and number of grains per pod. But diameter of stem indicated partial dominance near complete dominance. 2. Estimates of genetic variance components; In the degree of dominance,. eight characters, that is, days to flowering, days from flowering to maturity, days to maturity, length of internode, number of pods per plant, number of grains per pod, number of grains per plant and grain weight per plot were expressed larger than 1. And the characters, days from flowering to maturity, number of branches per plant and number of grains per plant as the degree of mean dominance ($H_1$/D) were found to be negative value over other characters. On the other hand, apprent asymmetry of dominance-recessive allele ($H_2$ /$4H_1$) produced comparatively estimates with lower value on days from flowering to maturity, length of internode, number of branches per plant and number of grains per pod. 3. Analyses of combining ability; Mean square value of GCA(general combining ability) appeared to be more important than those of SCA (specific combining ability) for most characters, and among them, grain weight per plot showed the highest mean square value in GCA and SCA. 4. Effect of combining ability; Variety 178 was expressed as the highest GCA effects in five characters (days to flowering days to maturity, number of pods per plant, number of grains per plant and grain weight per plot). SCA effects were differed from parents, characters and crosses, but crosses between TVu 1857 $\times$ TVu 2885 and TVu 2702 $\times$ J78 were shown to be highly with SCA effects on yield.

• Magazine of the Korean Society of Agricultural Engineers
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• v.7 no.1
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• pp.861-876
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• 1965

During my stay in the Netherlands, I have studied the following, primarily in relation to the Mokpo Yong-san project which had been studied by the NEDECO for a feasibility report. 1. Unit hydrograph at Naju There are many ways to make unit hydrograph, but I want explain here to make unit hydrograph from the- actual run of curve at Naju. A discharge curve made from one rain storm depends on rainfall intensity per houre After finriing hydrograph every two hours, we will get two-hour unit hydrograph to devide each ordinate of the two-hour hydrograph by the rainfall intensity. I have used one storm from June 24 to June 26, 1963, recording a rainfall intensity of average 9. 4 mm per hour for 12 hours. If several rain gage stations had already been established in the catchment area. above Naju prior to this storm, I could have gathered accurate data on rainfall intensity throughout the catchment area. As it was, I used I the automatic rain gage record of the Mokpo I moteorological station to determine the rainfall lntensity. In order. to develop the unit ~Ydrograph at Naju, I subtracted the basic flow from the total runoff flow. I also tried to keed the difference between the calculated discharge amount and the measured discharge less than 1O~ The discharge period. of an unit graph depends on the length of the catchment area. 2. Determination of sluice dimension Acoording to principles of design presently used in our country, a one-day storm with a frequency of 20 years must be discharged in 8 hours. These design criteria are not adequate, and several dams have washed out in the past years. The design of the spillway and sluice dimensions must be based on the maximun peak discharge flowing into the reservoir to avoid crop and structure damages. The total flow into the reservoir is the summation of flow described by the Mokpo hydrograph, the basic flow from all the catchment areas and the rainfall on the reservoir area. To calculate the amount of water discharged through the sluiceCper half hour), the average head during that interval must be known. This can be calculated from the known water level outside the sluiceCdetermined by the tide) and from an estimated water level inside the reservoir at the end of each time interval. The total amount of water discharged through the sluice can be calculated from this average head, the time interval and the cross-sectional area of' the sluice. From the inflow into the .reservoir and the outflow through the sluice gates I calculated the change in the volume of water stored in the reservoir at half-hour intervals. From the stored volume of water and the known storage capacity of the reservoir, I was able to calculate the water level in the reservoir. The Calculated water level in the reservoir must be the same as the estimated water level. Mean stand tide will be adequate to use for determining the sluice dimension because spring tide is worse case and neap tide is best condition for the I result of the calculatio 3. Tidal computation for determination of the closure curve. During the construction of a dam, whether by building up of a succession of horizontael layers or by building in from both sides, the velocity of the water flowinii through the closing gapwill increase, because of the gradual decrease in the cross sectional area of the gap. 1 calculated the . velocities in the closing gap during flood and ebb for the first mentioned method of construction until the cross-sectional area has been reduced to about 25% of the original area, the change in tidal movement within the reservoir being negligible. Up to that point, the increase of the velocity is more or less hyperbolic. During the closing of the last 25 % of the gap, less water can flow out of the reservoir. This causes a rise of the mean water level of the reservoir. The difference in hydraulic head is then no longer negligible and must be taken into account. When, during the course of construction. the submerged weir become a free weir the critical flow occurs. The critical flow is that point, during either ebb or flood, at which the velocity reaches a maximum. When the dam is raised further. the velocity decreases because of the decrease\ulcorner in the height of the water above the weir. The calculation of the currents and velocities for a stage in the closure of the final gap is done in the following manner; Using an average tide with a neglible daily quantity, I estimated the water level on the pustream side of. the dam (inner water level). I determined the current through the gap for each hour by multiplying the storage area by the increment of the rise in water level. The velocity at a given moment can be determined from the calcalated current in m3/sec, and the cross-sectional area at that moment. At the same time from the difference between inner water level and tidal level (outer water level) the velocity can be calculated with the formula $h= \frac{V^2}{2g}$ and must be equal to the velocity detertnined from the current. If there is a difference in velocity, a new estimate of the inner water level must be made and entire procedure should be repeated. When the higher water level is equal to or more than 2/3 times the difference between the lower water level and the crest of the dam, we speak of a "free weir." The flow over the weir is then dependent upon the higher water level and not on the difference between high and low water levels. When the weir is "submerged", that is, the higher water level is less than 2/3 times the difference between the lower water and the crest of the dam, the difference between the high and low levels being decisive. The free weir normally occurs first during ebb, and is due to. the fact that mean level in the estuary is higher than the mean level of . the tide in building dams with barges the maximum velocity in the closing gap may not be more than 3m/sec. As the maximum velocities are higher than this limit we must use other construction methods in closing the gap. This can be done by dump-cars from each side or by using a cable way.e or by using a cable way.