• Korean Journal of Cognitive Science
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• v.16 no.4
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• pp.305-322
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• 2005

Watermarking is a widely employed method tn protecting copyright of a digital image, the owner's unique image is embedded into the original image. Strengthened level of watermark insertion would help enhance its resilience in the process of extraction even from various distortions of transformation on the image size or resolution. However, its level, at the same time, should be moderated enough not to reach human visibility. Finding a balance between these two is crucial in watermarking. For the algorithm for watermarking, the predefined strength of a watermark, computed from the physical difference between the original and embedded images, is applied to all images uniformal. The mean brightness or contrast of the surrounding images, other than the absolute brightness of an object, could affect human sensitivity for object detection. In the present study, we examined whether the detectability for watermark noise might be attired by image statistics: mean brightness and contrast of the image. As the first step to examine their effect, we made rune fundamental images with varied brightness and control of the original image. For each fundamental image, detectability for watermark noise was measured. The results showed that the strength ot watermark node for detection increased as tile brightness and contrast of the fundamental image were increased. We have fitted the data to a regression line which can be used to estimate the strength of watermark of a given image with a certain brightness and contrast. Although we need to take other required factors into consideration in directly applying this formula to actual watermarking algorithm, an adaptive watermarking algorithm could be built on this formula with image statistics, such as brightness and contrast.

• The Korean Journal of Malacology
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• v.17 no.1
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• pp.45-55
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• 2001

Gametogenes, reproductive cycle, first sexual maturity(biological minimum size), sex ratio and larval development of the marsh clam Corbicula japonica were investigated monthly by histological observations. Samples were collected in brackish water of Gokgang stream, Kyungsangbuk-Do, Korea, from August 1997 to July 1998. Sexuality of Corbicula japonica is dioecious and the species are an oviparous clam. The gonads are irregularly arranged from the sub-region of mid-intestinal gland in visceral cavity to reticular connective tissue of foot. The ovary is composed of a number of ovarian sac which are branched arborescent. Oogonia actively proliferate along the germinal epithelium of ovarian sac, in which young oocytes are growing. The testis is composed of a number of testicular tubules, and the epithelium of the tubule has function of germinal epithelium, along which spermatogonia actively proliferate. A great number of undifferentiated mesenchymal tissue and eosinophilic granular cells are abundantly distributed between developing oocytes and spermatocytes in the early developmental stages. With the further development of the ovary and testis these tissue and cells gradually disappear. Then the undifferentiated mesenchymal tissue and eosinophilic granular cells are considered to be related to the growing of the oocytes and spermatocytes. The spawning period is from July to September, and the main spawning occur between July and August when seawater temperatures reach above 22$^{\circ}C$. The reproductive cycle of this species can be divided into five successive stages; early active (February to April), late active (May to July), ripe (June to September), partially spawned (July to September), degenerative (September to October) and resting stage (October to February). Percentages of first sexual maturity of female and male clams ranging in length from 10 mm to 12 mm are over 50% and 100% for clams over 16.0 mm in shell length. Fertilized eggs or Corbicula japonica were 80-90 ${\mu}{\textrm}{m}$ in diameter. In the early embryonic development of C. japonica, the appearance of polar body, trochophore and D-shaped veliger were observed around 40 min., 27 hours and 4 days after spawning, respectively, at a water temperature of 26.5-28.$0^{\circ}C$. The size of larvae of early umbo stage was about 185-210 ${\mu}{\textrm}{m}$ in shell length, 160-180 ${\mu}{\textrm}{m}$ in shell height around 7 days after fertilization. The correlation of relative growth between the culture day (D) and shell length (SL) was expressed by the following simple formula from D-shaped veliger to metamorphosing stage; SL = 13.300D + 209.36($r^2$= 0.9078).

• Journal of dental hygiene science
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• v.14 no.4
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• pp.571-579
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• 2014

This study was conducted to provide basic data for improvement of the oral health management ability and the factors affecting oral health recognition and practice of 6th graders. The research subjects total 259 numbers of 6th grade students in two schools located in Changwon, it was investigated and analyzed with structured questionnaires. The collected data is analyzed by using IBM SPSS Statistics 19.0. The average oral health recognition score investigated were $3.19{\pm}0.41$, and $2.95{\pm}0.43$ for oral health practices. The oral health recognition was statistically significant differences by father's education (p<0.01), perceived oral health status (p<0.01), perceived grade (p<0.01), intention to attend oral health education (p<0.001). The oral health practices was statistically significant differences by father's education (p<0.01), perceived oral health status (p<0.001), perceived grade (p<0.05), parent's interest in child's toothbrushing (p<0.01), experience of oral health education (p<0.001), intention to attend oral health education (p<0.05). The factors that may improve the oral health recognition are in order of oral health practices, intention to attend oral health education, and parent's attention to child's tooth brushing. The factors that may improve the oral health practice was found to be in order of oral health recognition, parent's attention to child's tooth brushing, and perceived oral health status. As a result, in order to improve oral health management ability of 6th grade students, the surrounding environment, the attitude on oral care, the interest of oral, and the current disease status of oral health are required to be identified, then the oral health education program should be provided.

• Journal of dental hygiene science
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• v.7 no.1
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• pp.1-7
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• 2007

This study aimed to provide basic information on dental hygienists' practicing the prevention of infections by figuring out their actual conditions in dental clinics. The subjects of the study were the dental hygienists who participated in the continuing medical education of Incheon & Gyeonggi-do association and Seoul city association in October and November 2005 and the self-administered surveys were used for the prevention of infections. The results were as below. 1. In terms of education experiences of infection prevention, those who answered "there were" were 72 persons (42.9%) and those who followed the educational route for infection prevention were "through the in-house education from the hospital" and they were 42 persons (58%), which were highest. 2. In terms of the injury experiences, those who answered "there were" were 147 persons (87.5%) and the number of annual injury out of 147 persons with injury experiences was 7.7 time. For the tools that were damaged, 125 persons (75%) damaged the "explorer," which was highest. 3. For the experiences of being infected with contagious diseases, those who answered "there were" were 6 persons (3.6%) and there were four persons for "hepatitis B", one person for "rubella" and one person for "TB." 4. The questions with high practice scores were as in the following: "2. I wash my hands after conducting medical examinations (1.86 points)," "7. I always close the lid of a shot of Novocain after doing local anesthesia (1.86 points)" and "20. I separate and collect the wastes and give them to those who treat accumulated materials (1.85 points)". Meanwhile, the questions with low practice scores were as below: "16. I change my medical gowns (doctor wears) once a day (0.24 point)" and "I wash my medical gowns every time after examining patients with contagious diseases (0.52 points)." 5. The question with high knowledge was as below: "1. The contagion during the dental treatment is determined by source of infection, infection methods, infection routes and the host that is prone to infection (0.95 point)" and the question with the lowest knowledge was "5. HBV(hepatitis B) is destroyed after adding 95oC of heat for more than 5 minutes (0.27 points)." 6. The question with the highest organization-related factors was "I am always ready to use a mask, gloves, etc. if necessary" (0.89 points)" and the question with the lowest score was "There is a guideline that I can refer when I am exposed to dangerous situations related to the contagion in my workplace (0.33 point)." 7. In terms of the equipment conditions of protectors in medical environments, 168 persons for (disposable) mask (100%), 167 persons for disposable gloves (Latex) (99.4%), which meant that most of them were equipped with them. On the contrary, 108 persons (64.3%) are equipped with the protectors for frontal faces, which is the lowest and 165 persons (98.2%) said that they had autoclave in their disinfecting and sterilizing devices.

• Journal of Korean Home Economics Education Association
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• v.29 no.4
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• pp.1-14
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• 2017

This study described the status of family dining and personality of adolescents, determined the differences in family dining according to personal variables, and examined the relationship between family dining and personality in adolescence. The Data were collected from self-reported inventory of the middle and high school students in a city and 1,259 data copies were used for analyses. Data were analyzed for frequency, percentage, mean, standard deviation, Cronbach's ${\alpha}$, t-test, ANOVA, scheffe test, and multiple regression analysis using SPSS/PC 18.0 program. The results obtained were as follows. First, as for the weekly family dining frequency, more than 7 times had the most number of responses(44.2%), followed by 1~2 times(20.8%), 3~4 times(18.1%), 5~6 times(12.9%). The average scores for family dining perception and family dining attitudes were 3.75 and 3.42 on a 5-Likert scale, respectively, which means moderately high. But, family dining rules was 2.80, which means moderate. Agreeableness was the highest(3.68) among the personality components followed by Openness/intellect(3.42), Extraversion(3.33), Conscientiousness(3.14), and Emotional Stability(3.05) out of 5-point Likert scale. Second, there were statistically significant differences in family dining frequency, family dining perception, family dining rules, and family dining attitudes depending on the gender, school level, and the father's academic attainment. Third, family dining frequency, family dining perception, and family dining attitudes had statistically significant influence on the personality of adolescents after personal variables were considered. But, there was no significant relationship between family dining rules and the personality. The outcomes indicate that family dining affects the personality of adolescents. School needs to offer quality programs with various teaching methods to enhance family dining frequency, family dining perception, and family dining attitudes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.132-139
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• 2017

The purpose of this study was to obtain data for contribution of job characteristics (workload, autonomy, reward, community, fairness, and value) to job burnout (emotional exhaustion, and cynicism), and job engagement (vigor, dedication, and absorption) in foodservice dietitians. Our survey was administered to 393 school foodservice dietitians in the Busan area on February 11, 2014. The mean scores of nutrition teachers were significantly higher for autonomy (P<0.01), reward (P<0.05), community (P<0.01), fairness (P<0.001), and value (P<0.001) than unlimited period contract dietitians. The mean scores of high school dietitians were significantly higher for emotional exhaustion (P<0.01) and cynicism (P<0.001) than elementary school dietitians and middle school dietitians. Workload (r=-0.609, P<0.001), reward (r=-0.417, P<0.001), and fairness (r=-0.394, P<0.01) correlated significantly with emotional exhaustion. Reward (r=-0.324) and value (r=-0.423) correlated significantly (P<0.01) with cynicism. Value correlated significantly (P<0.01) with vigor (r=0.493), dedication (r=0.480), and absorption (r=0.460). Workload (${\beta}=-0.521$, P<0.001) had the highest negative influence on emotional exhaustion, whereas value (${\beta}=-0.325$, P<0.001) had the highest negative influence on cynicism. Value had the highest positive influence on vigor (${\beta}=0.392$, P<0.001), dedication (${\beta}=0.443$, P<0.001), and absorption (${\beta}=0.444$, P<0.001). Based on the results of this study, school management should plan job characteristics strategies to reduce workload and increase value for school foodservice dietitians.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.3
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• pp.21-29
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• 2017

In this study of visitor place attachment to parks, Scannel and Gilford considered the dimensions of place attachment, and proposed the theoretical framework of PPP(Place, Person, Process) that should be systematically studied from the perspective of person, place and psychological processes. According to Scannel's theoretical basis, this paper puts forward the hypothesis of a structure model of place attachment. In the model, the five independent variables of people, places, cognition, emotion, and behavior have influenced the dependent variable of place attachment. The questionnaire was conducted on 18 neighborhood parks in Kunming, China, and the residents of the 5 neighborhood parks in Daejeon, South Korea. A total of 1,645 valid samples of the questionnaire survey were collected. Through confirmatory factor analysis(CFA) results of the inspection of the various elements, it was shown that the reliabilities of 6 latent variables, such as people, places, cognition, affection, behavior and place attachment, which were composed with the observed variables(30 observed variables in Daejeon, 19 observed variables in Kunming), were all above 0.7 and the data were fit for this study. The hypothesis test results found that the physical environment of the neighborhood parks such as a comfortable environment, pleasant road and convenient facilities would increase the rate of visitors coming back. From the park management perspective, to increase the amount of visitors to the park, the park should increase visibility, provide more organized, varied activities and meetings, or special exhibitions according to the particular characteristics of the individual park, to increase awareness of the park. From the park visitors' psychological perspective, visitors are seeking to enjoy the park facilities and environment not only to bring physical relaxation, but also to bring about a psychological cure. With the commonality of attachment structure between the two countries, to improve the place attachment of neighborhood park visitors, collecting regularly visitor feedback will facilitate the sustainable development of neighborhood park attachment.

• Journal of agricultural medicine and community health
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• v.27 no.2
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• pp.17-26
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• 2002

Reducing the level of stress and insomnia by aromatherapy is proposed as a method of self-care and health promotion in the future. Of the people who received aromatherapy from July, 1999 to February, 2000 at the Complementary and Alternative Medicine Center at the Gyeongu City Health Center, 48 people agreed to participate in a questionnaire survey, presented before and after their aromatherapy, and the data were analyzed. When the people received aromatherapy at the Complementary and Alternative Medicine Center, they inhaled the aroma from a vaporizer and when at home, they inhaled from a tissue, gauze or washbowl. Two sessions per week (2 hrs./session) were provided at the Center in the total 1-month duration of the therapy. The oil made from a blend of clarysage, geranium, rose at a ratio of 3:2:1 was used for relieving stress, and the oil made from a blend of clarysage, lavender, and lemon at 2:2:1 ratio was used for relieving insomnia. The scores of stress of 92.5 17.5 points before aromatherapy significantly reduced to $87.4{\pm}4.2$ points after therapy(p<0.01), and the scores of insomnia of $2.5{\pm}1.2$ points before aromatherapy significantly reduced to $1.0{\pm}1.1$ points after therapy(p<0.01). The reduction in stress and insomnia from aromatherapy was more significant in those who were experiencing high levels of stress and insomnia. Therefore, stress and its related insomnia can be effectively relieved with proper application of aromatherapy. With benefits such as little side-effects, convenient and simple education, low cost, and the do-it-yourself feature. aromatherapy can be expanded into a self-management program for promoting health of the community people.

• Journal of agricultural medicine and community health
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• v.38 no.4
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• pp.229-242
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• 2013

Objectives: The objective of this study was to identify the influence of shift work on sleep quality, daytime sleepiness, and perceived errors during nursing work among hospital nurses. Methods: The study subjects were 209 hospital nurses working in two general hospitals in South Korea. The data were collected through self-administered questionnaires in May 2013. Sleep quality was measured using Korea Pittsburgh Sleep Quality Index (PSQI-K), daytime sleepiness was measured using Epworth Sleepiness Scale (ESS), and perceived errors in past 6 months during nursing duty hours with the tool developed in this study. Results: The sleep quality was significantly worse among rotating shift nurses when compared to fixed day duty nurses. However, the odds ratio (OR) of 1.92 [95% confidence interval(CI): 0.58-6.37] adjusted for sociodemographic variables, health behaviors, and working environment in logistic regression was not significant. There was no significant difference in the daytime sleepiness between rotating shift nurses and fixed day duty nurses in both simple and multivariable analyses. There were significantly more perceived errors in rotating shift nurses than fixed day duty nurses. However, the OR of 1.26 (95% CI: 0.38-4.21) adjusted for sociodemographic variables, health behaviors, working environment, sleep quality, and daytime sleepiness in logistic regression was not significant. Depression (OR=3.31, 95% CI: 1.11-9.84) and daytime sleepiness(OR=1.18, 95% CI: 1.07-1.30) were significantly associated with perceived errors in logistic regression. Conclusion: This study suggested shift work among hospital nurses had no independent influence of sleep quality, daytime sleepiness, and perceived errors. However, daytime sleepiness had independent influence of perceived errors. More studies are warranted to achieve more reliable conclusion.

• Journal of the Korean Society of Radiology
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• v.6 no.2
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• pp.151-157
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• 2012

General treatment for cholangiocarcinoma is complete surgical resection. However recurrence is common in those patients. In most of cases the purpose of the treatment for patients with recurrent is palliative. Therefore we adopt intraluminal catheter to treat a recurrent patient with high-dose-rate intraluminal brachytherapy. This study aims to evaluate the treatment procedure and set-up reproducibility of intraluminal brachytherapy in the recurrent patient. Study patient was diagnosed at rcT1N0M0 and undergone intraluminal brachytherapy after Arrow Sheath insertion. 3 Gy was delivered in every fraction with a total dose of 30 Gy. We planned dose normalization at distal, proximal and central axis point of narrowed bile duct far from 1 cm. To evaluate set-up reproducibility, we measured distance between distal, proximal treatment target volume point and anterior surface of the thoracic vertebral body respectively for five times before every treatment with dummy seed insertion. Mean distance between distal, proximal treatment target volume point and anterior surface of 10th and 11th thoracic vertebral bodies is 0.5 cm, 6.1 cm and standard deviation is 0.06, 0.08 respectively. In addition, set-up reproducibility was maintained significantly. The patient has been alive with no evidence of disease recurrence for more than a year and has not yet reported severe complications. In conclusion, high-dose-rate intraluminal brachytherapy for unresectable recurrence of cholangiocarcinoma maintains high set-up reproducibility without severe side effects.