• Journal of Positioning, Navigation, and Timing
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• 제10권3호
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• pp.197-206
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• 2021

We compared two typical ensemble time scale algorithms; AT1 and Kalman filter. Four commercial atomic clocks composed of two hydrogen masers and two cesium atomic clocks provided measurement data to the algorithms. The allocation of relative weights to the clocks is important to generate a stable ensemble time. A 30 day-average-weight model, which was obtained from the average Allan variance of each clock, was applied to the AT1 algorithm. For the reduced Kalman filter (Kred) algorithm, we gave the same weights to the two hydrogen masers. We also compared the frequency stabilities of the outcome from the algorithms when the frequency offsets and/or the frequency drift offsets estimated by the algorithms were corrected or not corrected by the KRISS-made primary frequency standard, KRISS-F1. We found that the Kred algorithm is more effective to generate a stable ensemble time scale in the long-term, and the algorithm also generates much enhanced short-term stability when the frequency offset is used for the calculation of the Allan deviation instead of the phase offset.

• PNF and Movement
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• 제9권1호
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• pp.11-19
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• 2011

The purpose of this study was to investigate whether it makes difference to use of the Augmented Feedback Type(Verbal Feedback, VTR Feedback and Verbal & VTR Feedback) to hemiplegic adults on learning of motor skill. For the purpose 15 hemiplegic adults who are received rehabilitation program at H hospital in Hong-Sung, Choong-Nam Province. Subjects were classified into three groups by random assignment; the Verbal Feedback group, the VTR Feedback group and Verbal & VTR Feedback group. Each groups received 5 subjects from hemiplegic adults. Subjects were tested by Timed Up and Go test for 9 weeks. And to find out the improvement measured by Pre-Test, Acquisition Test and Retention Test. To find out the improvement of each group's measures took average and standard deviation. To probate the significance of difference between the improvement conducted the one-way ANOVA and to probate the significance of difference of Acquisition Test and Retention test conducted paired t-test. The results of this study were as follows; First, All of Augmented Feedback Types had a positive effect on hemiplegic adults to learning of motor skill. Second, The Verbal Feedback group and the VTR Feedback group had no significantly difference at Acquisition Test, But They had the most improvement at Retention Test. Third, In hemiplegic adults, the Verbal & VTR Feedback group had the highest Retention Effect.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제19권2호
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• pp.112-119
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• 2008

Objectives : This study was conducted to examine whether there are qualitative differences in attention problem among children with various psychiatric disorders, including attention-deficit hyperactivity disorder (ADHD), depressive disorder, anxiety disorder, and tic disorder using clinical ADHD diagnostic system (ADS) T-scores. Methods : The subjects were 794 outpatient children aged from 5 to 15 years, including 540 children with ADHD, 95 children with depressive disorder, 86 children with anxiety disorder, and 73 children with tic disorder. Clinical T-scores on the ADS were calculated using the mean and standard deviations of four ADS variables for the ADHD group. Results : All four groups had T-scores on the ADS in the abnormal range. However, when comparing the clinical T-scores, the children with depressive and anxiety disorders performed better than the children with ADHD. We also found that although the four groups seemed to be similar in terms of clinical T-scores for omission and commission errors, there were significant differences in clinical T-scores for reaction time and the standard deviation of response time (RT) between the ADHD and other groups. Conclusions : We concluded that inattention and impulsivity might not be specific only to ADHD and that the clinical T-scores of RT and standard deviation of RT on the ADS could be used to discriminate between ADHD and other clinical groups.

• Safety and Health at Work
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• 제12권2호
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• pp.244-248
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• 2021

Background: Sunburn is the main avoidable cause of skin cancer. Beach lifeguards spend many hours exposed to the effects of solar radiation during their work day, precisely at times of the year when levels of solar irradiation are highest. The aim of this study is to quantify the risk to beach lifeguards of sun exposure. Methods: A descriptive cross-sectional study was carried out in the Western Costa del Sol, southern Spain, during the summer of 2018. The research subjects were recruited during a skin cancer prevention course for beach lifeguards. All participants were invited to complete a questionnaire on their habits, attitudes, and knowledge related to sun exposure. In addition, ten were specially monitored using personal dosimeters for three consecutive days, and the results were recorded in a photoprotection diary. A descriptive analysis (mean and standard deviation for the quantitative variables) was performed, and inter-group differences were evaluated using the Mann-Whitney U test. Results: Two hundred fifteen lifeguards completed the questionnaire, and 109 met the criteria for inclusion in this analysis. The mean age was 23.8 years (SD: 5.1), 78.0% were male, 71.5% were phototype III or IV (Fitzpatrick's phototype), and 77.1% had experienced at least one painful sunburn during the previous summer. The mean daily personal ultraviolet exposure per day, the minimal erythema dose, and the standard erythema dose, in J/m², were 634.7 [standard deviation (SD): 356.2], 2.5 (SD: 1.4) and 6.35 (SD: 3.6), respectively. Conclusion: Beach lifeguards receive very high doses of solar radiation during the work day and experience correspondingly high rates of sunburn. Intervention strategies to modify their sun exposure behavior and working environment are necessary to reduce the risk of skin cancer for these workers and to promote early diagnosis of the disease.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제42권
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• pp.11.1-11.8
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• 2020

Background: The purpose of this study is to compare the skeletal stability of two-jaw surgery via surgery-first approach with conventional two-jaw surgery in facial asymmetry patients by measuring the skeletal changes after surgery from a three-dimensional analysis. From January 2010 to January 2014, 40 patients with facial asymmetry who underwent two-jaw surgery in Pusan National University Hospital were included in this study. They were classified into experimental group (n = 20) who underwent two-jaw surgery via surgery-first approach and control group (n = 20) who underwent conventional two-jaw surgery. After selection of 24 landmarks and the construction of horizontal and sagittal, coronal reference planes, changes in 10 linear measurements and 2 angular measurements were compared between the surgery-first approach and conventional groups in the preoperative, immediate postoperative, and postoperative periods. The paired t test and Student t test were used for statistical analysis. The mean and standard deviation of the measurement were calculated for the experimental and control groups. Results: The statistical analysis showed that changes in skeletal measurements were similar between the surgery-first approach and conventional groups, according to each period. However, U1-SRP measurement showed statistically significant changes in surgery-first approach groups at postsurgical change (T1 to T2). Also, the mean treatment duration in the treatment group was 15.9 ± 5.48 months whereas that in the control group was 32.9 ± 14.05 months. Conclusion: In facial asymmetry patients, similar results were observed in the postoperative skeletal stability when 2-jaw surgery via surgery-first approach was compared with conventional 2-jaw surgery. However, significant lateral deviation of upper incisor midline was observed. In addition, a shorter average treatment duration was observed. To stabilize the unstable occlusion after surgery, increased wearing of the stent and proactive rubber guidance will be needed.

• Child Health Nursing Research
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• 제15권1호
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• pp.88-96
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• 2009

Purpose: This study was done to investigate effects of Meridian massage on the growth of the infant and on mother-infant interaction, mother-infant attachment, and the mother's satisfaction with her mothering role. Method: The participants were 39 mothers of infants who were seen at one of two urban public health centers located in Yangju or Seoul. Data were collected from February 2008 to December 2008. Infants in the experimental group were given Meridian massage for 50 minutes (lecture 20 minutes, practice 15 minutes, preparation and arrangement 15 minutes) once a week for 6 weeks. Percentages, means with standard deviation, $X^2$-test, repeated measured ANOVA, and ANCOVA were used with the SPSS program to analyze the data. Results: Infants in the experimental group showed an increase in weight & height compared to those in the control group. Mother-infant interaction, mother-infant attachment, and satisfaction with mothering role were significantly higher in the experimental group than the control group. Conclusion: The above finding suggest that Meridian massage should be applied in clinical practice to improve growth of infants, interaction and attachment between infants and their mothers, and the mother's satisfaction with her mothering role.

• 한국동물위생학회지
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• 제14권2호
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• pp.148-153
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• 1991

To investigate epidemological sitution of bovine viral diarrhea infection, serological survey in cattle being raised in Young Dong province were conducted. Bovine sera collected ramdomly from August 1990 to December 1990 were tested for bovine viral diarrhea virus serum neutralizing antibody titers. The results were as follows 1. BVDV SN antibody levels were considerably varies and positive rate was 58(108 heads out of 186) 2. BVDV SN antibodies to breeds of cattle was various and positive rates showed that diary cattle, beef, native cattle(Korean) were 67.52%, 59.38%, 27.00％ respectively followed in that order. 3. In the regional prevalence of BVD SN antibodies in cattle, Alpine(92％) was the highest, Young Dong south(59%) middle(44%), and North 30% followed in that order 4. In the age relatated prevalence of BVD SN antibodies, the younger than 6 month old group was the highest 65.7%, and older than 25 month old group was also at 62.2％. Then, 7 to 12 moth old group and 13 to 24 month old group showed to 58.5%, 52.1％ respectively. 5. The geometric mean titer (log2) of 108 cattle serum samples showing positive BVD SN antibodies was 4.3. 6. In the geometric mean titer(log2) according to age, younger than 6 month old group (5.2) was the highest, then 7 to 12 month old group 2.8(SD=1.94 standard deviation) was lowliest.

• 한국안전학회지
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• 제35권2호
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• pp.17-27
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• 2020

To identify the relationship between types of employment(regular and non-regular group) and departments classification (administration, product and research group) and the levels of recognition of chemical substances, a total of 117 workers in cosmetics workplaces. Mainly, regular group and research group showed higher recognition of chemical substances (PPE, ventilation, chemical management, hazards in handling chemicals, skin contact) than non-regular group and administration, product group, but In some cases, production and administrative groups were high. Descriptive statistics(SAS ver9.2)was performed. the results of recognition of chemical substances were analyzed the mean and standard deviation by t-test, and anova, (P=0.05). These results cosmetics manufacturing workplaces have normal level of the perception of chemical substances. In most of the employment types, the regular workers showed high recognition, and the working departments showed high recognition in the research and production groups. Therefore, OEM and ODM cosmetics manufacturers regularly identify characteristics and needs of workplaces and workers, and suggest the development of experience and practiced education programs and risk assessment tools that can raise worker awareness.

• Child Health Nursing Research
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• 제12권3호
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• pp.351-358
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• 2006

Purpose: This study was attempted to find out the differences of characteristics between potential substance-abuse group and healthy group of middle school students in Busan. Method: The participants were 458 middle school students in Busan. The data were collected from 1st September 2004 to 31th October 2004 using structured questionnaire, and then were analyzed by SPSS-WIN 10.0 program with frequency, percentage, mean, standard deviation and $X^2-test$. Results: 23.6% of the subjects have been smoking, and 16.2% of them have been drinking. 18.6% of the subjects was classified to potential substance-abuse group based on the cut-point suggested by Lee et al.. The characteristics of potential substance-abuse adolescents are that they have religion and siblings, that their parents have divorced, that they don't live with their parents, and that their perceived health state is bad. Conclusion: Based on the findings of this study, It is necessary to develop a substance abuse prevention education program for potential substance-abuse group.

• 한국의류학회지
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• 제22권6호
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• pp.781-792
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• 1998

The purpose of this study was to investigate the factors related to the propensity for symbolic consumption and the effects of materialism, reference group, and social stratification on the symbolic consumption in clothing. Data were administered to 957 adolescence in middle, high school, and college student living in Seoul, Chonju, Sunchon, Yousu, and Kwangyang from May to June 1997. For analysis of the data, frequencies, percentage, means, standard deviation, factor analysis, 1-test, one-way anomia, duncan's multiple range test, and multiple regression analysis were employed. The results of this study can be summarized asfollows. 1) Symbolic consumption, materialism, and reference group were found to have the significant differences according to social stratification groups by objectivemethod. The higher social stratification is, the higher symbolic consumption, materialism, and reference group were. 2) symbolic consumption were proven to have the significant differences according to materiaiism and reference group. The higher materialism and the influence of referencegroup indicated, the higher symbolic consumption. 3)according to the results of the regression analysis examining the relative influences of variables affecting symbolic consumption in clothing, the relative importance of the variables are in order of : the influences of the reference group, materialism, social stratification, status inconsistency type (occupation-income), and their explanatory power totalled 40.0%.