• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.154-155
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• 2012

The promise of nano-crystalites (nc) as a technological material, for applications including display backplane, and solar cells, may ultimately depend on tailoring their behavior through doping and crystallinity. Impurities can strongly modify electronic and optical properties of bulk and nc semiconductors. Highly doped dopant also effect structural properties (both grain size, crystal fraction) of nc-Si thin film. As discussed in several literatures, P atoms or radicals have the tendency to reside on the surface of nc. The P-radical segregation on the nano-grain surfaces that called self-purification may reduce the possibility of new nucleation because of the five-coordination of P. In addition, the P doping levels of ${\sim}2{\times}10^{21}\;at/cm^3$ is the solubility limitation of P in Si; the solubility of nc thin film should be smaller. Therefore, the non-activated P tends to segregate on the grain boundaries and the surface of nc. These mechanisms could prevent new nucleation on the existing grain surface. Therefore, most researches shown that highly doped nc-thin film by using conventional PECVD deposition system tended to have low crystallinity, where the formation energy of nucleation should be higher than the nc surface in the intrinsic materials. If the deposition technology that can make highly doped and simultaneously highly crystallized nc at low temperature, it can lead processes of next generation flexible devices. Recently, we are developing a novel CVD technology with a neutral particle beam (NPB) source, named as neutral beam assisted CVD (NBaCVD), which controls the energy of incident neutral particles in the range of 1~300eV in order to enhance the atomic activation and crystalline of thin films at low temperatures. During the formation of the nc-/pm-Si thin films by the NBaCVD with various process conditions, NPB energy directly controlled by the reflector bias and effectively increased crystal fraction (~80%) by uniformly distributed nc grains with 3~10 nm size. In the case of phosphorous doped Si thin films, the doping efficiency also increased as increasing the reflector bias (i.e. increasing NPB energy). At 330V of reflector bias, activation energy of the doped nc-Si thin film reduced as low as 0.001 eV. This means dopants are fully occupied as substitutional site, even though the Si thin film has nano-sized grain structure. And activated dopant concentration is recorded as high as up to 1020 #/$cm^3$ at very low process temperature (＜ $80^{\circ}C$) process without any post annealing. Theoretical solubility for the higher dopant concentration in Si thin film for order of 1020 #/$cm^3$ can be done only high temperature process or post annealing over $650^{\circ}C$. In general, as decreasing the grain size, the dopant binding energy increases as ratio of 1 of diameter of grain and the dopant hardly be activated. The highly doped nc-Si thin film by low-temperature NBaCVD process had smaller average grain size under 10 nm (measured by GIWAXS, GISAXS and TEM analysis), but achieved very higher activation of phosphorous dopant; NB energy sufficiently transports its energy to doping and crystallization even though without supplying additional thermal energy. TEM image shows that incubation layer does not formed between nc-Si film and SiO2 under later and highly crystallized nc-Si film is constructed with uniformly distributed nano-grains in polymorphous tissues. The nucleation should be start at the first layer on the SiO2 later, but it hardly growth to be cone-shaped micro-size grains. The nc-grain evenly embedded pm-Si thin film can be formatted by competition of the nucleation and the crystal growing, which depend on the NPB energies. In the evaluation of the light soaking degradation of photoconductivity, while conventional intrinsic and n-type doped a-Si thin films appeared typical degradation of photoconductivity, all of the nc-Si thin films processed by the NBaCVD show only a few % of degradation of it. From FTIR and RAMAN spectra, the energetic hydrogen NB atoms passivate nano-grain boundaries during the NBaCVD process because of the high diffusivity and chemical potential of hydrogen atoms.

• Journal of dental hygiene science
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• v.9 no.3
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• pp.353-360
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• 2009

The purpose of this study was to investigate the recognition for improvement of the Korean Dental Hygienists' Licensing Examination(KDHLE). The subjects were 1,048 dental hygienists were surveyed. either in person or through mail. Data was collected using a self administrated questionnaire from July 1 to July 20, 2008. The data were analysed with frequency and $x^2$-test using the SPSS 15.0 windows. For the inquiry where adequacy of subjects of the KDHLE regarding to evaluation of standard duty achievement ability in the real field was asked, 404(39.5%) answered 'Yes', and 680(66.9%) was answered 'Yes' for necessity of changing current subjects of the KDHLE. For the inquiry about the number of questions in the KDHLE, 353(34.6%) answered that current number of questions is 'Inappropriate' and advisable way of improving KDHLE subjects, 463 (45.4%) answered 'enhancing problem solving ability through unifying subjects', the highest of all. About practical examination methods, 647(67.3%) was answered 'Should be modified'. For methods of dental hygienist practical examination, 'clinical demonstration on patients' received the highest number of votes 628(63.6%). According to the above results, most of active dental hygienists at presence expect the alteration of current KDHLE and new items which are reliable for globalization by testing problem solving ability through unified subjects must be introduced.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.13 no.1
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• pp.67-75
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• 2002

Objectives：This study was conducted to investigate the degree of psychopathologies of the family members of children with chronic convulsive disorder and evaluate the structures and dynamics of those families. Methods：The participant patients and family members were recruited from the population attending the outpatient clinic of department of pediatric neurology in Seoul National University Hospital in Korea. All the patients had idiopathic chronic convulsive disorder. Any patient with mental retardation, pervasive developmental disorder and gross brain pathology was excluded. As controls, normal students were chosen and their sex, age, achievement, socioeconomic status were matched to patients. The author interviewed the children and their family members twice and obtained informations about patient-parent relationship, patient-sibling relationship and others. For in-depth evaluation, we used family environment scales(FES), symptom Checklist-90-revised(SCL-90-R), self administered dependency questionnaire for mother(SADQ). Results：After interviewing with the parents of epileptic children, overprotection of parents, hostile feeling of siblings toward index children were higher than controls. The parental conflict was also more expressed than control families. According to results from FES, the scores of the subscales of expression, achievement-orientation, intelligence-orientation and active recreation were significantly lower than control group. The epileptic children showed higher dependency to parents especially in affection, communication and traveling areas of SADQ than control group. Maternal psychopathologies evaluated by SCL-90-R were much higher than the mothers of controls. According to T scores of SCL-90-R, about 40% of mothers with epileptic children had the risk of clinically significant depressive or anxiety disorders. Conclusion：These results suggested that the family members of epileptic children had more relationship problems and psychopathologies than control group and some mothers might have clinically significant depressive or anxiety disorders. so, effective psychiatric family interventions are needed for resolution of conflict and psychopathologies of family members.

• Journal of Nutrition and Health
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• v.48 no.4
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• pp.335-343
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• 2015

Purpose: The aim of this study was to evaluate the food behavior and nutritional status of elementary school students in the Jeju area using Nutrition Quotient (NQ). Methods: The subjects were 440 students (235 boys and 205 girls) in the fifth and sixth grade at four elementary schools located in Jeju. Demographic, lifestyle, and environmental information was collected using a self-reported questionnaire. The food behavior checklist for children's Nutrition Quotient (NQ), consisting of 19 items, and nutrition education related information were also obtained. Results: The mean score of the children's NQ was poor, reaching 60.3 points. The percentage distribution of NQ grade was 19.8% (lowest), 18.6% (low), 45.0% (medium), 10.7% (high), and 5.9% (highest) and the factor scores for balance, diversity, abstinence, regularity, and practice were 56.6, 68.4, 71.3, 57.4, and 54.8 points, respectively. Compared with the NQ cut-off points for defining malnutrition (balance; 57, diversity; 87, abstinence; 66, regularity; 69, and practice; 67 point), average score of abstinence factor was only above the cut-off point and scores of the other factors were below the cut-off point. Subjects with higher NQ scores tended to have higher levels of exercise activity (p < 0.001), frequency of family meals (p < 0.01), and father's educational levels (p < 0.01) compared to those with lower NQ score. NQ score showed positive association with nutrition education experience and practice (p < 0.001). Conclusion: NQ score of elementary school students residing in Jeju was lower than the national average. More opportunities should be provided for participation in nutrition education, which incorporates a range of program strategies, as well as communication and education activities.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.420-432
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• 2011

Population dynamics of greenhouse whitefly, Trialeurodes vaporariorum (Westwood), were modeled and simulated to compare the temperature effects of air and tomato leaf inside greenhouse using DYMEX model simulator (pre-programed module based simulation program developed by CSIRO, Australia). The DYMEX model simulator consisted of temperature dependent development and oviposition modules. The normalized cumulative frequency distributions of the developmental period for immature and oviposition frequency rate and survival rate for adult of greenhouse whitefly were fitted to two-parameter Weibull function. Leaf temperature on reversed side of cherry tomato leafs (Lycopersicon esculentum cv. Koko) was monitored according to three tomato plant positions (top, > 1.6 m above the ground level; middle, 0.9 - 1.2 m; bottom, 0.3 - 0.5 m) using an infrared temperature gun. Air temperature was monitored at same three positions using a Hobo self-contained temperature logger. The leaf temperatures from three plant positions were described as a function of the air temperatures with 3-parameter exponential and sigmoidal models. Data sets of observed air temperature and predicted leaf temperatures were prepared, and incorporated into the DYMEX simulator to compare the effects of air and leaf temperature on population dynamics of greenhouse whitefly. The number of greenhouse whitefly immatures was counted by visual inspection in three tomato plant positions to verify the performance of DYMEX simulation in cherry tomato greenhouse where air and leaf temperatures were monitored. The egg stage of greenhouse whitefly was not counted due to its small size. A significant positive correlation between the observed and the predicted numbers of immature and adults were found when the leaf temperatures were incorporated into DYMEX simulation, but no significant correlation was observed with the air temperatures. This study demonstrated that the population dynamics of greenhouse whitefly was affected greatly by the leaf temperatures, rather than air temperatures, and thus the leaf surface temperature should be considered for management of greenhouse whitefly in cherry tomato grown in greenhouses.

• Korean Journal of Biological Psychiatry
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• v.6 no.2
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• pp.153-160
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• 1999

Animal models can provide a useful tool for the study of some aspects of psychiatric disorders and their treatment. The four criteria for the evaluation of animal models of psychiatric disorders are as following : 1) similarity of inducing conditions 2) similarity of behavioral state 3) common underlying neurobiological mechanisms 4) reversal by clinically effective treatment techniques. Several animal models have been proposed for schizophrenia : phenylethylamine model, L-dopa model, hallucinogen model, cocaine model, amphetamine model, phencyclidine model, noradrenergic reward system lesion model, reticular stimulation model, social isolation model, conditioned avoidance reaction, catalepsy test, paw test, self-stimulation paradigms, latent inhibition paradigms, blocking paradigms, prepulse inhibition of the startle reflex, rodent interaction, social behavior in monkeys, hippocampal damage, high ambient pressure, and models using selective breeding. Among them, animals with bilateral lesion of the hippocampus may provide an adequate animal model for several symptoms of schizophrenia, and ketamine model can reproduce negative symptoms and cognitive deficits as well as positive symptoms of schizophrenia. In conclusion, no model of schizophrenia is entirely representative of the disease, and findings gleaned from model systems must be cautiously interpreted. Furthermore, the process of developing and validating animal models must work in concert with the process to identify reliable measures of human phenomenology.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.2
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• pp.151-158
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• 2010

This study was conducted to evaluate the feed value and growth characteristics of Sasa quelpaertensis Nakai by horse grazing in the woodland of Jeju. Crude protein (CP), NDF, ADF and minerals contents at different growth stages of Sasa quelpaertensis were analyzed. The apparent digestibilities of DM, CP, NDF and ADF were determined by total collection method using 5 Jeju horses. The yield and growth characteristics of S. quelpaertensis Nakai by horse grazing were investigated. CP contents in the currentand the previous-year-sprouted leaves of S. quelpaertenisis were $16.6{\pm}1.0%$ and $12.2{\pm}1.1%$, respectively. The digestibility of DM, CP, NDF and ADF in the current-year-sprouted leaves of S. quelpaertenisis were $47.2{\pm}1.2$, $67.8{\pm}1.0$, $47.0{\pm}1.3$ and $47.1{\pm}1.1%$, respectively. The current-year-sprouted S. quelpaertenisis tended to have high nutritional values and digestibilities compared to those of the previous-year-sprouted. The dry matter yield, plant length, leaf width and density of S. quelpaertensis Nakai were clearly decreased by horse grazing. These results show that considering the feed value and growth characteristics, the natural S. quelpaertenisis Nakai can be used as a feed source for horses.

• Journal of Plant Biotechnology
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• v.42 no.2
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• pp.71-76
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• 2015

Developed countries have set seed industry as a new growth engine, which demands strong support from the government. Multinational seed companies such as Monsanto and DuPont have made huge financial investment to secure their major roles in the global market. To spur domestic seed industry performance, Korean government laid out the foundation for developing seed industry through policy promotion in the late 2000s. In this paper, I look at the current state of the domestic and international seed market to provide information for improving the efficiency of the propulsion of the Golden Seed Project (GSP) along with its vision. The increasing size of global giant companies has been regarded to monopolize the world seed industry wherein ten renowned companies occupy 73% of the overall global market. In effect, this causes a price hike due to limited seed choices. Domestic seed market has been stuck in a range due to a sustained low agricultural production resulting in decreased seed demand and market size. Though breeding technologies for rice and vegetables are world-class, the technologies for top global crops such as cabbage, paprika, and forage are insufficient therefore professionals in this field are not easily employed. Moreover, there is a lack in appropriate infrastructure set up in the universities which adds to ineffective training of professionals. Being a key-supporting industry for agriculture, seed industry should be granted with strong and sustainable investment support from the government. In view thereof, GSP, which started in 2012, ambitions to spur researches outlined by excellent professionals in universities and seed companies aimed to drive seed export volume and quality and attain domestic seed self-sufficiency through adoption of export- and import-substitution seed types (10 varieties each) development strategies. To develop Korea's seed industry excellent achievement of GSP's goals should be drawn successfully and to do this beside development of high quality seeds, support programs for promotion of seed exports are also needed.

• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.168-177
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• 2001

Sanitary management practices were assessed to insure the safety of school foodservice, to prevent the outbreak of foodborne illness, and to improve the quality of school foodservice. To accomplish these objectives, a survey was conducted and analyzed on elementary and high school foodservice operations located in Seoul area. A Questionnaire from based on HACCP standards was developed and used for self-reported evaluation of the school foodservice managers on their sanitary management practices. The results were analysed by examining their activities and identifying weaknesses in those activities. The questionnaire was composed of three sectors with all 53 questions; 33 questions for time-temperature management, 5 for personal hygiene and 15 for equipment/facility sanitation. Five-point-scale was used on the questionnaire answers. Among the schools responded,253 (98.4% of the total) were elementary schools and 19 (1.6%) were high schools. Among the three sectors, personal hygiene performance was mostly well conducted by marking average 4.06$\pm$0.57. Equipment/facility sanitation came next by marking average 3.84$\pm$0.53. Time-temperature marked average 3.45$\pm$0.46. “Storage after cooking (2.03$\pm$0.94)”was identified as the least managed activities because the school foodservice operations were not equipped well with hot holding and/or cold holding. “Separate use of sink per usage (3.03$\pm$1.10)” and “proper location of hand washing facility (3.07$\pm$1.13))” were identified as the least practiced activities in equipment/facility sanitation sector. To enhance these practices, proper number of sinks and hand washing facilities should be equipped first within the kitchen area.

• Clinical and Experimental Pediatrics
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• v.51 no.10
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• pp.1058-1064
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• 2008

Purpose : This study aimed to assess current knowledge of and training experiences with the intraosseous (IO) line among emergency medicine (EM) and pediatric residents who care for critically ill children and to evaluate the educational effectiveness of the IO line workshop. Methods : During May and June 2008, a workshops on IO line insertion was held for EM and pediatric residents. The workshop comprised a 45-min lecture and a 15-min hands-on session. A semi-drill type EZ-IO machine was used for education. Self-assessment questionnaires gauged residents knowledge of and experiences with IO line insertion or bone marrow (BM) examination and their confidence with IO line insertion before and after the workshop. Performance tests were completed for skill evaluation. Results : Forty-five pediatric residents and 22 EM residents participated in the workshop. The pre-educational questionnaire revealed that EM residents had more educational experience in IO line insertion than pediatric residents (P<0.001), while pediatric residents reported more experience in BM examination (P<0.001). The post-educational questionnaire showed a statistically significant higher percentage of correct answers (P<0.001). Although the pediatric residents inserted an IO line more quickly (P=0.001), most residents (88.7%) succeeded in IO line insertion on their first attempt; there was no difference in the groups success rates. Both groups showed higher confidence in performing IO line insertion after training (P<0.001). Conclusion : Observed educational effectiveness in both knowledge and confidence of IO line insertion skill suggest educational opportunities for pediatric and EM residents should be increased.