• Aerospace Engineering and Technology
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• v.12 no.2
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• pp.108-117
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• 2013

The oxidizer shutoff valve of a gas generator controls the mass flow rate of the propellant of a rocket engine using pilot pressure and spring the force of the valve. The developing oxidizer shutoff valve can be shut off if the pilot pressure is removed from the actuator. Therefore, force balancing is necessary to analyze the characteristics of the forces with respect to the opening and closing of the valve in order to evaluate its performance. In light of this, the valve has been designed to adjust the control pressure required to open the poppet and to determine the working fluid pressure at which the valve starts to close. Under cryogenic flow test as a tests level of C.R.T(Control Random Test), the chattering phenomena occurred due to much leakage of a metal seat section. The pressure for chattering of the oxidizer valve is predicted at about 11 bar using force balancing analysis.

• Journal of Microbiology and Biotechnology
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• v.25 no.1
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• pp.98-108
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• 2015

Staphylococcus aureus is an important foodborne pathogen that causes diverse diseases ranging from minor infections to life-threatening conditions in humans and animals. To further understand its pathogenesis, the genome of the strain S. aureus FORC_001 was isolated from a contaminated food. Its genome consists of 2,886,017 bp double-stranded DNA with a GC content of 32.8%. It is predicted to contain 2,728 open reading frames, 57 tRNAs, and 6 rRNA operons, including 1 additional 5S rRNA gene. Comparative phylogenetic tree analysis of 40 complete S. aureus genome sequences using average nucleotide identity (ANI) revealed that strain FORC_001 belonged to Group I. The closest phylogenetic match was S. aureus MRSA252, according to a whole-genome ANI (99.87%), suggesting that they might share a common ancestor. Comparative genome analysis of FORC_001 and MRSA252 revealed two non-homologous regions: Regions I and II. The presence of various antibiotic resistance genes, including the SCCmec cluster in Region I of MRSA252, suggests that this strain might have acquired the SCCmec cluster to adapt to specific environments containing methicillin. Region II of both genomes contains prophage regions but their DNA sequence identity is very low, suggesting that the prophages might differ. This is the first report of the complete genome sequence of S. aureus isolated from a real foodborne outbreak in South Korea. This report would be helpful to extend our understanding about the genome, general characteristics, and virulence factors of S. aureus for further studies of pathogenesis, rapid detection, and epidemiological investigation in foodborne outbreak.

• Journal of The Korean Society of Integrative Medicine
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• v.12 no.1
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• pp.97-108
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• 2024

Purpose : In this study, we aimed to determine the impact of the COVID-19 pandemic on nursing students' adjustment to college life by focusing on their empathic ability, perceived stress, and resilience. Methods : We applied a descriptive survey research design, which included a self-report questionnaire. The participants comprised 307 nursing students in B city. The data were analyzed by calculating the percentages, means, standard deviations, t-tests, ANOVA, Scheffé test, Pearson's correlation coefficients, and hierarchical regression using SPSS 23.0. Results : The participants' empathic ability score was 3.30±.42, perceived stress score 1.85±.49, resilience score 3.44±.64, and adjustment to college life score 3.25±.52. Adjustment to college life was positively correlated with resilience (r=.43, p<.001) but negatively correlated with perceived stress (r=.27, p<.001). Factors affecting adjustment to college life include, among general characteristics in Model 1, in descending order, major satisfaction-satisfied (β=.54, p<.001), interpersonal conflict: never (β=.26, p=.018), health status: healthy (β=.25, p=.002), character: positive (β=.21, p=.006), character: optimistic (β=.19, p=.015), parents' economic power: high (β=.15, p=.047), and gender: male (β=.11, p=.016). Model 1 was statistically significant (F=11.67, p<.001), and the explanatory power was 41 %. In Model 2, empathic ability, perceived stress, and resilience were added as independent variables. When including the dependent variables, the factors that most influenced adjustment to college life were perceived stress (β=-.37, p<.001), major satisfaction-satisfied (β=.36, p<.001), health status-healthy (β=.25, p<.001), gender-male (β=.10, p=.015), and resilience (β=.10, p=.029). Model 2 was statistically significant (F=17.65, p<.001), and the explanatory power was 56 %. Conclusion : We found that gender, major satisfaction, health status, perceived stress, and resilience affected adjustment to college life among nursing students who had experienced the COVID-19 pandemic. To increase their ability to adjust to college life, a gender-specific intervention program should be developed that can improve the students' health status, major satisfaction and resilience, and reduce their perceived stress.

• Korean Journal of Biological Psychiatry
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• v.1 no.1
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• pp.98-108
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• 1994

The etiology and pathophysiology of schizophrenia remain unknown. It has been postulated that infectious-autoimmune process may play a role in the pathogenesis of symptoms in some schizophrenic patients. Findings of altered interleukin(IL) regulation have been regarded as additional proof that schzophrenia has an infectious-autoimmune background. In the present study, we measured mitogen-stimulated production of and serum level of IL-$1{\beta}$, IL-2, IL-6 using ELISA in 16 neuroleptic-free schizophrenic patients and in 16 age, sex matched healthy controls. The results were as follows : 1) There was a significant decrease of IL-2 production in schizophrenic patients than in normal controls(respectively $1.90{\pm}0.13ng/m{\ell}$, $2.79{\pm}0.14ng/m{\ell}$, p<0.001). But there was no significant difference of IL-$1{\beta}$ production and IL-6 production between schizophrenic patients and normal controls. 2) There was a significant increase of serum level of IL-2 in schizophrenic pateitns than in normal controls(respectively $184.8{\pm}12.8pg/m{\ell}$, $104.2{\pm}34.2pg/m{\ell}$, p<0.01). Serum level of IL-$1{\beta}$ was partially detected in both groups and serum level of IL-6 was not detected in both groups. 3) There was no significant differences of IL-$1{\beta}$, -2, -6 production & serum level of IL-2 according to male vs female, paranoid type vs undifferentiated type, drug-naive group vs drug-free group in schizophrenic patients. 4) There was significant correlation between IL-$1{\beta}$ and IL-6 production(r=0.86, p<0.001). No correlation between IL-$1{\beta}$, -2, -6 production, serum level of IL-2 and age, duration of illness, and BPRS score was found. It has been suggested that the low lymphocyte production of IL-2 in the patients with autoimmune disease occurs because the T cells are activated and lymphocyte-derived IL-2 has been released into the serum. The authors suggest that decreased IL-2 production in our schizophrenic patients is due to increased IL-2 serum level in those patients. Thus our finding of low IL-2 production and high serum level of IL-2 in our schizophrenic patients is compatible with the possibility that our patients have an autoimmune process. Further study on relationship between IL alteration and other immunological abnormalities(the presence of serum autoantibody and of anti-brain antibody, $CD4^+$, $CD8^+$ cell index, etc) in schizophrenic patients will be warranted.

• Journal of Veterinary Clinics
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• v.14 no.2
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• pp.319-337
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• 1997

The electrocardiographic (ECG) parameters in the normal Korean black goat have been measured with a 3-channel Electrocardiograph and computed, analyzed. ECG in 243 black goats were made with the limb leads (I, II, III, aVR, aVL, aVF), that were recorded conduction parameters of wave and interval, and were analyzed as to shape and amplitude of the P and T waves and the components of the QRS complex. Heart rate were recorded by the ECG which were a mean of 106.1$\pm $21.8 beats/min. Average conduction times in the PR, the QRS complex and the QTc interval were recorded 103.9$\pm $34.9 msec., 58.3$\pm $23.2 msec. and 302.6$\pm $67.8 msec., in the P and T wave duration recorded 24.8$\pm $6.4 msec. and 51.7$\pm $10.8 msec. respectively. The shape of wave in each leads were observed various types, and any spacial wave type appeared the highest frequency in each lead that ware shown less than 60%, and these frequent rate and average amplitudes as fallow: 1. In P waver the frequent rate and average amplitudes of the positive type showed in leads I, II and aVL that were 54.8% (93.0$\pm $ 33.2 $\mu $V), 50.5% (90.1$\pm $30.5 $\mu $V) and 41.7% (58.5$\pm $ 31.1 $\mu $V). Average amplitude of the negative type showed the frequent rate of 49.8% in lead aVE which was -77.6$\pm$ 25.2 $\mu $V. Biphasic type in leads III and aVF were 46.1% (108.4 $\mu $V, -90.2 $\mu $V.) and 45.7% (137.4 $\mu $V, -105.4 $\mu $V.), and amplitudes between positive and negative of it were significant difference. 2. The highest amplitudes of the QRS complex in all leads were 534.8$\pm $ 232.3 $\mu $V of lead II. The frequent rate and amplitudes of the R wave type in the I, II, III and aVF were 30.2% (277.8 $\pm $131.3 $\mu $V), 45.1% (393.1$\pm $114.2 $\mu $V), 48.5% (349.3$\pm $178.3 $\mu $V) and 54.9% (334.4$\pm $129.7 $\mu $V), and QS ways type in the lead aVL was 49.5% (359.2$\pm $195.5$\mu $V), and RS and QS wave types in the lead a VR were 43.3% (312.4 $\mu $V, -212.7 $\mu $V.) and 41.1% (399.2$\pm $92.2 $\mu $V), respectively. 3. In T wave, the frequent rata and amplitudes of the positive type in the leads I, II, III and aVF were 44.6% (207.9$\pm $ 97.1 $\mu $V), 41.6% (245.1$\pm $92.1 $\mu $V), 46.9% (189.8$\pm $ 82.7 $\mu $V) and 53.0% (195.4197.8 $\mu $V), and the negative in the lead aVR was 41.2% (-230.7$\pm$ 103.1 $\mu $V), respectively. The positive and negative types in the lead aVe appeared with same frequent rate of 43.2%.4. Frontal plane vectors for P, QRS, and T were found to lie at 38.1$\pm $ 21.5, 142.0$\pm $ 57.2, and 117.2$\pm $ 63.9 degrees, respectively. These results in ECG of goats may be served to the limited purposes as to conduction parameters, arrhythmias except abnormal ECG because of waveforms, amplitudes and electrical axis of it were variability.

• Journal of dental hygiene science
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• v.9 no.1
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• pp.99-108
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• 2009

The purpose of this study was to investigate the effect of oral health education practice and schoolteacher's self-efficacy on oral health attitude. The data of 217 dental hygienists was subjected to path analysis using AMOS 16.0. Oral health knowledge, attitude, self-efficacy and oral health education practice of schoolteacher were measurement variables of three path models. The goodness of fitness of Knowledge-Attitude-Practice model and Knowledge-Attitude-Self efficacy -Practice model were acceptable. The regression weights of two models were statistically significant. Oral health education practice of schoolteacher gave impact on oral health attitude by mediation of self-efficacy of schoolteacher. Self-efficacy of schoolteacher was a important determinant of oral health education practice. Oral health attitude and practice were supposed to be mutual determinants of health behavior models.

• 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.

• Journal of Korean Academy of Nursing
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• v.29 no.3
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• pp.625-638
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• 1999

The purpose of this study was to identify the relationships among health promoting behaviors, Health Locus of Control(HLOC), and response patterns to HLOC in Korean elderly. The sample was composed of 162 healthy elderly ranging in age from sixties to eighties. The instruments for this study were modified Health Promoting Lifestyle Profile (45 items, 4 scales), and Multidimensional Health Locus of Control (18 items). For the in data analysis, SPSS PC$^{＋}$ program was uilized for descriptive statistics, Pearson correlation, t-test, ANOVA and Stepwise multiple regression. The results of the study are as follows : 1. The total mean score for the HPLP was 2.411 (range 1-4), and the mean scores on the subscales were 3.324 for nutition, 2.709 for interpersonal support, 2.495 for exercise,2.225 for health responsibility, 2.205 for self actualization, 2.026 for stress management. 2. The mean scores for the HLOC in the elderly were HLOC-I : 23.531, HLOC-P : 21.914, HLOC-C : 18.667. 3. The response patterns of the HLOC identified eight types, pure internal, pure powerful others, pure chance, double external, believers in control, yea sayer, nay sayer and complex control. The “believers in control” was the largest group (22.8%), and “yea sayer” was the next largest group(17.9%). The “nay sayer”(5%) was the smallest group. 4. Demographic variables, such as education, economic status, religion and the perception of the health status showed strong connections to health promoting behaviors. 5. The HLOC-I and health promoting behavior were correlated positively(r＝.165, P＝.017), but the HLOC-P, the HLOC-C and the health promoting behavior were not correlated at the level of statistical significance. 6. There was not significant difference in health promoting behavior depending on the response patterns of the HLOC(F=1.171, P=.108). But, there were significant differences in two subscales of health promoting behavior exercise (F=3.279, P=.002), and stress management (F=3.165, P＝.003). 7. Education, the perception of the health and economic status explained 21.0% of the variance for health promoting behaviors. These results suggest that several demographic factors are important factors in predicting the level of health promoting behaviors in elderly. So to enhance the health promoting behavior, nurses should use the different nursing strategies depending on the demographic characters of the elderly.

• Journal of Gifted/Talented Education
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• v.10 no.2
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• pp.87-108
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• 2000

This study analyzes the factors influencing self-esteem of the gifted children. The factors are divided into the environmental ones and innate ones. The purposes of this study is presented as follows. 1) To analyze the environmental factors influencing self-esteem of the gifted children (1) whether the education period affects self-esteem of the gifted children? (2) what influences do the manners of parental child-rearing behavior make? (3) what influences do peer relationships make on self-esteem of the gifted children? 2) To analyze the innate factors influencing self-esteem of the gifted children (1) does the gender make a difference to self-esteem of the gifted children? (2) does the level of intelligence make a difference to self-esteem of the gifted children? (3) what influences does the locus of control make on the self-esteem of the gifted children? To solve these questions 120 gifted children were selected, who were taking a special education program at C Korea Academy of Gifted Education located at Yangjae-dong Seocho-gu. They were 1st to 3rd grades at elementary school. We used Hare Self-Esteem Scale developed by Bruce R. Hare in 1985, the Index of Peer Relations developed by Hudson in 1986, and Nowicki & Strickland Locus of Control Scale developed by Nowicki and Strickland in 1973. At the other hand the nursing behaviors of 120 mothers of the gifted, were also investigated, based on the Korean Maternal Behavior Inventory, developed by Sungyeon Park in 1989 with some modifications. For statistical analysis we adopted SPSS, a computer software, and calaulated the coefficient of internal appropriateness and the frequencies and percentages of general aspects of the cases. We analysed the factors influencing the self-esteem of the gifted children by way of Pearson's product moment correlation coefficient, t-test, ANOVA, and multiple regression analysis and Duncan for ex-post-facto approval. The results of this study can be summarized as follows. 1) Influences of the environmental factors on the self-esteem of the gifted children: (1) The duration of education period had a significant effect on the self-esteem; the longer the duration were, the higher self-esteem they possessed. (2) Of parental child-rearing behaviors, active involvement had positive influence on the self-esteem; on the contrary, authoritarian control and overprotection had negative influences on the self-esteem. (3) An acceptable peer relationship had a positive influence on the self-esteem of the gifted children. 2) Influences of individual innate characteristics on the self-esteem of the gifted children: (1) The gender made no difference on the self-esteem of the gifted. (2) The intelligence did not have a statistically significant effect on the self-esteem of the gifted. (3) When the locus of control was external, the self-esteem of the gifted tended to be low.

• Journal of the Korean Society of School Health
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• v.9 no.1
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• pp.99-108
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• 1996

The purpose of the survey was to identify the degree and the relationship of sexual knowledge, sexual attitude and need of sex education. This information will provide useful data for a more systematic. desirable, and practical sex education. The data was collected from 300 first grade schoolchildren (150 boys and 150 girls) of two Junior high school in K city. The data was gathered by questionnaire from Nov.21 to 28, 1995. The questionnaire was modified by authors using the questionnaire developed by Lief & Reed. Data was analyzed by using the statistical computer package, SAS to manipulate the data along with percentages, means, standard deviation, t-test, $X^2$-test, GLM, and Pearson correlation coeffiency. The results in this study were summarized as follows: 1. Sexual knowledge. - The mean score of sexual knowledges showed no significant differences between boys and girls(p<0.6180), but in the areas of biological differences(boys; $11.57{\pm}2.43$, girls; $10.93{\pm}2.41$, p<0.0242), and pregnancy physiology(boys; $9.28{\pm}1.87$, girls; $10.04{\pm}2.42$, p<0.0026) showed significant difference between boys and girls. 2. Sexual attitudes. - The mean score of sexual attitudes showed no significant difference between boys and girls (p<0.8286), but in the areas of masturbation (boys : $6.69{\pm}2.22$, girls : $5.65{\pm}1.88$, p<0.0001), and premarital intercourse (boys : $5,42{\pm}1.35$, girls : $6.00{\pm}1.33$, p<0.0002) showed significant difference between boys and girls 3. Need of sex education. - The majority of the subjects wanted to learn about sexual delinquency and it's prevention(57.7%), form a friendship with the other sex(56.3%), physical differences of the other sex(52.0%), psychological differences and the charateriatics of the other sex (50.3%) and meaning of love(50.3%). 4. The relationships between sexual knowledges and sexual attitudes. - Those who had higher sexual knowledges showed more positive attitudes towards sex, and showed statistical significance(r=0.2074, p<0.0003). 5. The relationships between general charateristics and sexual knowledge. - Better students(by self-perception of school performance) had higher knowledge scores about sex. 6. The relationships between general charateristics and sexual attitudes. - Those who wanted to learn more about sex, and better students had higher attitude scores about sex. - Those who were in high standard of living had higher attitude scores about sex as well. Suggestions based on above study are as follows' 1. The planned sex education showed be performed to the schoolchildren establish responsible attitudes about sex. 2. Systematic sex education through formal school education according to age is recommended. 3. Further studies should be done to measure the effect of sex education based on the needs of the schoolchildren.