• Journal of Korea Game Society
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• v.4 no.4
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• pp.11-18
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• 2004

The on-line games in the past were played by only two persons exchanging data based on one-to-one connections, whereas recent ones (e.g. MMORPG: Massively Multi-player Online Role-playings Game) enable tens of thousands of people to be connected simultaneously. Specifically, Korea has established an excellent network infrastructure that can't be found anywhere in the world. Almost every household has a high-speed Internet access. What made this possible was, in part, high density of population that has accelerated the formation of good Internet infrastructure. However, this rapid increase in the use of on-line games may lead to surging traffics exceeding the limited Internet communication capacity so that the connection to the games is unstable or the server fails. expanding the servers though this measure is very costly could solve this problem. To deal with this problem, the present study proposes the load distribution technology that connects in the form of local clustering the game servers divided by their contents used in each on-line game reduces the loads of specific servers using the load balancer, and enhances performance of sewer for their efficient operation. In this paper, a cluster system is proposed where each Game server in the system has different contents service and loads are distributed efficiently using the game server resource information such as CPU utilization. Game sewers having different contents are mutually connected and managed with a network file system to maintain information consistency required to support resource information updates, deletions, and additions. Simulation studies show that our method performs better than other traditional methods. In terms of response time, our method shows shorter latency than RR (Round Robin) and LC (Least Connection) by about 12%, 10% respectively.

• Journal of Life Science
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• v.23 no.9
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• pp.1170-1176
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• 2013

Essential oils have been used to treat psychophysiological disorders, but their effects on human electroencephalographic (EEG) activity have not been thoroughly investigated. We evaluated the effects of essential oil of Zizyphus jujuba seeds, a Korean folk medicine known as San-Jo-In, on human EEG activity. For this purpose, essential oil was extracted from San-Jo-In by the supercritical carbon dioxide extraction method. The effect of its inhalation on EEG activity was evaluated by measuring the EEG power spectrum (25 indices) in 20 healthy participants. The results of the EEG power spectrum indicated that the values of the theta wave decreased significantly (p<0.05) in the left (from 17.277 to $13.854{\mu}V$) and right parietal (from 15.324 to $13.020{\mu}V$) regions compared to the other regions. During the inhalation of San-Jo-In oil, the EEG spectrum values of fast alpha, relative gamma, and spectral edge frequency increased 50% compared to those before inhalation. The values of the fast alpha wave increased significantly (p<0.05) in the left prefrontal (from 0.063 to $0.085{\mu}V$), right prefrontal (from 0.064 to $0.085{\mu}V$), and left frontal (from 0.073 to $0.100{\mu}V$) regions following inhalation of the San-Jo-In essential oil. The changes in the EEG activities following inhalation of San-Jo-In suggest that the oil can improve psychological well-being by increasing attention and relaxation.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.4
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• pp.407-413
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• 1999

Maxillary duplication is a kind of proliferative neurocristopathy and considered to arise from bifurcation of neural crest elements soon after migration into mandibular arch. Sometimes this malformation is accompanied with oblique facial cleft. Usually this type of maxillofacial malformation requires multiple surgical intervention and the results are far from ideal. It became more troublesome if it had not been properly corrected on time, because secondary deformities could be developed from growth and development of abnormal tissues. This is a case of a 25-year-old-female patient who showed severe facial asymmetry thought to secondary deformity of maxillary duplication and masticatory disturbance due to multiple supernumerary teeth on posterior part right maxilla. We successully treated these deformities through four times of surgery of bone resection, orthodontic treatment, zygomatic and orbital reconstruction, orthognathic surgery and scar revision... ect. So we reported this rare case with review of literatures.

• Clinical and Experimental Pediatrics
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• v.50 no.2
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• pp.182-189
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• 2007

Purpose : The primary purpose of this study was to evaluate the growth and neuropsychologic function following treatments for pediatric hematologic and oncologic diseases. Healthy monozygotic twins served as ideal controls for comparison to exclude possible confounding factors. Methods : Seven children treated with various hematologic and oncologic diseases were included in the study: acute lymphoblastic leukemia (ALL; n=2), Diamond-Blackfan anemia twins (n=2), and aplastic anemia (n=3). The median age at the diagnosis was 5.2 (0.3-15) years. The median duration of follow-up was 7.2 (4.9-10) years. Controls were healthy monozygotic twins. Growth was measured and the percentile channels were evaluated sequentially for patients. The K-WISC III was applied and compared in 5 pairs of patients and controls. Results : Similar growth profiles were noted for the twins. The percentiles at diagnosis was 3-10 in 3, 25-50 in 2, and 50-75 in 2 cases. All patients stayed in their growth percentiles through follow-up, except for 1 patient who became obese. For IQ tests, the mean behavioral, verbal and full scale IQ scores of patients were 88.0, 93.8, and 89.8, respectively, and those from their corresponding controls were 92.2, 97.0, and 91.7 (P>0.05). However, 2 children who were treated for ALL had lower IQ scores. Conclusion : Similar growth profiles were observed in the monozygotic twins in terms of height and weight. The IQ scores of patients were similar to those of monozygotic twins. However, prophylactic CNS-directed therapy for leukemia might adversely affect the IQ scores. A further prospective study on larger number of twins is warranted.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.16 no.2
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• pp.219-230
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• 2005

Objectives : This study was designed to compare the demographic data, clinical characteristics, developmental delay, and psychological tests between childhood-onset and adolescent-onset schizophrenic in-patients. Methods Medical records of the 17 childhood-onset (very early onset) Schizophrenia and 16 adolescent-onset (early onset) Schizophrenia in-patients were reviewed. Sex, age, psychiatric past history, prodromal symptoms and period, subtype, co-morbid disease, developmental delay, prescribed drug and dosage, treatment response, intelligence quotient (IQ), and Rorschach test were evaluated. Results : The mean admission age of childhood-onset (very early onset) group and adolescent-onset (early onset) group were 12.69$({\pm}2.34)$ and 15.13$({\pm}1.04)$ years. The mean onset age of childhood-onset(very early onset) group and adolescent-onset (early onset) group were 10.79$({\pm}1.95)$ and 14.46$({\pm}0.82)$ years. The mean prodromal period of childhood-onset (very early onset) group and adolescent-onset (early onset) group were 15.94$({\pm}12.33)$ and 8.06$({\pm}6.10)$ month. The time to remission period of childhood-onset (very early onset) group and adolescent-onset (early onset) group were 50.58$({\pm}24.67)$ and 30.06$({\pm}18.04)$ days. Longer time to remission period in childhood-osnet (very early onset) group was associated with earlier age of onset. The mean of total IQ, performance IQ, verbal IQ were at an average level. Discussion : Childhood-onset (very early onset) group and adolescent-onset (early onset) group Schizophrenia had different clinical and psychological features including prodromal period, and IQ subtests.

• The Korean Journal of Nuclear Medicine
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• v.34 no.6
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• pp.445-455
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• 2000

Purpose: We evaluated the distribution of hypoperfusion in patients with traumatic brain injury (TBI) and the relationship of thalamic hypoperfusion to severity of cognitive and behavioral sequelae. Materials and Methods: Tc-99m ECD SPECT and MRI were performed in 103 patients (M/F=81/22, mean age $34.7{\pm}15.4$ yrs) from 0.5 to 55 months (mean 10.3 months) after TBI. The patients were divided into three groups showing no abnormalities (G1), focal (G2) and diffuse injury (G3) on MRI. Psychometric tests assessed 11 cognitive or behavioral items. In all patients, we evaluated the distribution of hypoperfused areas in SPECT, and in 57/103 patients, neuropsychological (NP) abnormalities in patients with thalamic hypoperfusion were compared with those of patients without thalamic hypoperfusion. Results: The perfusion deficits were most frequently located in the frontal lobe (G1, 42.3%: G2 34.5%: G3 33.3%), temporal lobe ($24{\sim}26%$) thalami ($21{\sim}22.4%$), parietal and occipital lobe (${\leq}10%$). Numbers of NP abnormalities in the cases of cortical hypoperfusion with or without concomitant thalamic hypoperfusion were following: the former $4.7{\pm}1.5$ and the latter $3.2{\pm}1.4\;in\;G1,\;5.0{\pm}1.1\;and\;4.8{\pm}1.2\;in\;G2,\;6.8{\pm}1.8\;and\;6.3{\pm}1.1\;in\;G3$, respectively. This difference according to thalamic hypoperfusion was significant in G1 (p=0.002), but was not significant in G2 or G3. Conclusion: SPECT in patients with TBI had demonstrated hypoperfusion mostly involving the frontal, temporal and thalami. In normal group on MRI, frontal hypoperfusion was more prominent than that of any other group, Furthermore in this group, SPECT could predict severity of NP outcome by concomitant thalamic hypoperfusion with cerebral cortical abnormalities.

• Journal of Dental Rehabilitation and Applied Science
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• v.39 no.4
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• pp.237-249
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• 2023

Orofacial dystonia is a neuromotor disorder that causes irregular or repetitive movements of the face, lips, tongue, and jaw involuntarily, also called tic disorder. Edentulous patients with these symptoms experience functional and aesthetic problems, including difficulty using complete dentures, speech and swallowing difficulties, and orofacial pain. In this case, for a patient with orofacial dystonia who experienced complete edentulism at a relatively young age, restorative treatment was performed with a maxillary complete denture with bilateral posterior zirconia occlusal surfaces and a mandibular implant-supported fixed prosthesis, and continuous smile training was performed. The aim was to improve the aesthetics of facial muscles. As a result of the treatment, the patient was very satisfied with not only improved chewing function and aesthetics, but also regained psychological stability and was able to lead a normal daily life, so we would like to report this.

• Clinical and Experimental Pediatrics
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• v.48 no.7
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• pp.701-705
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• 2005

Purpose : Parents' genetic information plays an important role in their children's genetic expression. Human chromosome has 23-paternal chromosomes and 23-maternal chromosomes. Parental chromosomal translocation can induce clinical problems in their children because of imbalance in genetic information. We intent to analyze the cytogenentic and clinical features about children with maternal balanced translocation between chromosome 15 and 18. Methods : We detected by one family's FISH study of chromosome 15. We have evaluated children born to clinically normal parents about peripheral bood analysis, endocrine, metabolic, radiologic study, electroencephalogram and social & intelligence scale. and We analysis their clinical manifestation by hospital records. Results : Patient's father and elder sister are normal clinically and genetically. Her mother's chromosome show balanced translocation, 46, XX, t(15;18)(p11.2;p11.3). One child has 46, XX, der(18) t(15;18)(p11.2;p11.3), mental retardation, growth retardation, speech & social developmental delay, recurrent infection and mild mitochondria dysfunction. Her young brother has 46, XY, der(15) t(15;18) (p11.2;p11.3), mental retardation, aggressive behavior, obesity and speech developmental delay. Conclusion : In this study we observed the children with developmental delay, dysmorphic facial features, mental retardation, growth retardation associated with growth hormone deficiency and aggressive behavior due to unbalanced translocation between chromosome 15 and 18.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.6 no.1
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• pp.3-17
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• 1995

The so-called borderline children are characterised by disturbances in the sense of reality and interpersonal relationships, lack of control, fluctuation of functioning, uneven development and excessive anxiety. But the concept of borderline disorder of childhood is very difficult to define and diagnose in current classification system. The present study adapted the consensus symptoms in borderline children by Bemporad and Vera eight cases aged 7-11 were examined in 37 variables. Results are as follows 1) All subjects are boys and girl hardly be diagnosis n current diagnostic system and have many concurrent diagnoses. Common chief complaints in the sense of reality. 2) In KEDI-WISC test, the borderline children showed average intelligence, but performance IQ tends to be higher than verbal IQ. In Rorscharch test, they showed high thought disorder index, emotional instabilities and aggressive impulses. The results of TOVA suggested attentional deficit in half of the subjects. The organicity is not prominent. 3) Many of the borderline children were unwanted baby. Although primary care takers of all the subjects were their mothers there were moderate problems in caring attitude of their children and marital relationship with their husband. Sccioeconomic status was generally below middle class. Most of all subjects have delayed language development, but have overcome subsequently. Many subjects were rejected by peers because of their aggression. 4) The first visit of the subjects was about 6 years of age. Average duration of treatment was 2 years. All of them were treated in the outpatient basis except one. The effect of pharmacotherapy was doubtful and the necessity of long term play therapy was suggested. Although there were many limitations of method in present study, it was suggested that further research is needed for diagnostic criteria, epidemiology and treatment.

• Korean Journal of Cognitive Science
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• v.34 no.2
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• pp.111-151
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• 2023

It is reported that binge drinkers show cognitive impairment similar to alcohol use disorder patients. A previous studies using neuropsychological tests and brain imaging techniques to investigate the visual perception of alcohol use disorder patients reported that they had global-local visual perception defects. Although the neurological basis for the global-local visual perception deficit in the heavy drinking group has been presented, there are no studies to date that have investigated the global-local visual perception in the heavy drinking group. This study investigated local-biased visual perception in female college students with binge drinking (BD) using event-related potentials (ERPs). Based on the scores of the Korean version of Alcohol Use Disorder Identification Test and the Alcohol Use Questionnaire, participants were assigned into BD (n=25) and non-BD (n=25) groups. Local-global visual processing was assessed using a local-global paradigm, in which large stimuli (global level) composed of small stimuli (local level) were presented. The stimuli presented at global and local levels were either congruent or incongruent. The behavioral results exhibited that the BD and non-BD groups did not differ in terms of accuracy and response time. In terms of ERPs, the BD and non-BD groups did not show difference in N100, P150 and N200 amplitude. However, the BD group showed significantly smaller P300 amplitude than non-BD group especially in the local condition. In addition, a negative correlation between P300 amplitude and binge drinking score was observed, i.e., severer binge drinking smaller P300 amplitude. The P300 is known to reflect cognitive inhibition and attentional allocation. In the global-local paradigm, the local condition required to attend to local target while ignoring global non-target. Therefore, the present results indicate that female college students with BD do not have local-biased visual processing, instead they seem to have difficulties in inhibition of irrelevant stimuli.