• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.554-555
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• 2012

주문관리시스템은 여러 고객들로부터 다양한 주문에 대응하여 물류센터에 적정한 재고관리하기 위해 필요한 수량만큼 공장으로 주문을 관리하는 시스템이다. 일반적으로 주문관리시스템에서 사용하는 재고관리기법은 품목별로 ABC 분석을 통하여 정기발주법, 정량발주법, 2개 선반법이 주로 사용되고 있다. 그러나 이러한 발주법은 물류센터에 보관되는 제품의 특성이 다품종 소량 및 라이프사이클이 점차 짧아짐에 따라 재고부족 또는 과잉재고를 가져와 고객에 대한 서비스 감소 또는 재고유지비가 증가하는 문제점을 갖는다. 본 논문에서는 물류센터 내 적정한 재고를 유지하기 위해 퍼지기법을 활용하여 정기발주법과 정량발주법의 혼합한 지능형 주문관리시스템의 설계 방안을 제안한다.

• Journal of the Korean Vacuum Society
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• v.3 no.3
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• pp.346-354
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• 1994

삼원화합물 반도체 CuAlSe2 및 CuGaSe2 단결정의 solid solution 인 CuAl1-xGaxSe2 및 cobalt를 2.0 mol% 첨가한 CuAl1-xGaxSe2 : Co2+ 단결정을 iodine을 수송물질로 사용한 화학수송법으로 성장시켰 다. source material로는 CuAl1-xGaxSe2 의 화학조성비에서 Se를 3.0mol% 과잉으로 첨가하여 합성한 ingot를 사용하였으며 불순물이 첨가된 CuAl1-xGaxSe2:Co2+ 단결정성장시에는 source ma-terial 에 cobalt 분말을 2.0mol% 첨가하였다. X-선 회절무늬로부터 성장된 단결정들이 chalcopyrite 결정구조를 하고 있음을 확인하였으며 격자상수를 구하였다. 광흡수 spectra 측정으로부터 성장된 단결정에서 나타 는 cobalt 불순물에 의한 광흡수 peak가 Td 대칭점에위치한 Co2+ 이온의 에너지 준위들간 전자전이에 의해 나타남을 규명하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.62-62
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• 2007

ZnO 박막이 성장된 Si기판을 이용하여 Thermal evaporation을 사용하여 온도에 따라 합성된 1-D의 구조의 ZnO nanorods의 형상과 특성에 대하여 연구를 하였다. 합성온도는 $700^{\circ}C{\sim}900^{\circ}C$를 사용하였고 온도가 낮아짐에 따라 Vertical한 1-D ZnO가 합성이 되는 것을 알 수 있었다. 특히, $700^{\circ}C$에서 합성된 1-D ZnO는 ~100nm의 폭을 가지고 800nm의 길이의 Nanorods로 성장이 되는 것을 알 수 있었고, 상온 PL측정을 통해 온도가 증가함에 따라 O 결핍 또는 Zn의 과잉에 의한 Deep level emission이 증가하는 것을 알 수 있었다.

• The Korean Journal of Nuclear Medicine
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• v.29 no.3
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• pp.350-354
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• 1995

한국 원자력 연구소 부설 원자력병원에 설치된 AVF 싸이클로트론을 이용하여 요즈음 핵의학에 널리 사용되는 PET 용 싸이클로트론의 에너지를 검정 할 수 있고 양성자 과잉 핵종인 싸이클로트론 동위원소의 생산 수율에 중요한 변수인 양성자에너지를 탄소에 입사시켜 입사빔의 Range와 에너지를 측정하는 방법을 제시하였다. 본 실험에서 사용된 양성자 빔의 양성자 에너지는 35 MeV와 50 MeV 사이였으며, 탄소 막은 두께 6.3mm, 밀도 $1.712 g/cm^3$를 사용하였다. 탄소 표적물을 $0.9^{\circ}$씩 스텝 모터를 사용하여 회전시킴으로 두께를 변화 시켜 공칭 에너지에 대한 Range를 측정함으로써 입사된 양성자의 에너지를 구하였고 이를 인출반경과 RF주파수를 바탕으로 상대론 적으로 계산된 에너지와 비교하였다.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.8 no.1
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• pp.92-100
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• 1997

Objective：The objective of this study is to examine the clinical characteristics and behavioral comorbidity of patients with Tourette’s disorder. Method：Subjects consisted of 157 patients with Tourette’ disorder diagnosed by DSM-IIIR, who were examined and diagnosed from Jan. 1988 to May 1994 at the Tourette’s Clinic of Yonsei University Medical Center. Characteristics and behavioral comorbidity of Patients were assessed by a semi-structured interview schedule. Behavioral problems like hyperactivity, obsession-compulsion, self destructiveness, enuresis, sleep problem were assessed by global clinical impression. Results：The mean age of patients was 14.49(${\pm}7.99$) years. Patients consisted of 138 males (87.9%) and 19 females(12.1%). The sex ratio was 7：1, showing a male preponderance. The number of right-handers was 133(84.7%), and the number of non-right handers was 24(15.3%). Mean age of onset was 8.85(${\pm}4.56$) years, ranging from 2-to-16 years. More than half of the patients had their age of onset at 6-10 years. Bimodal peak in age of onset was observed；the first peak was around 6 and the second peak was around 10 years. There was no sex difference in bimodal age of onset. The most common initial symptom was eye blinking. More than 55% of patients reported eye blinking as their first symptom. The second common initial symptom was head turning and the third was vocal tic. The most common symptoms that patients reported on their first visit since onset were eye blinking(82.2%), head turning or nodding(57.9%), shoulder shrugging(52.7%) and forearm movement(32.6%). Of 157 cases, 101(64.3%) patients showed downward progression of symptoms, and 25(15.9%) showed upward progression of symptoms. Nineteen fathers(12%) of patients had a past history of obsessive-compulsive disorder(OCD). Seventeen fathers(10.6%) had a history of tic disorder. SSevenmothers(4.5%) had OCD, 4 mothers (2.5%) had tic disorder. One hundred and eighteen patients(75.1%) had comorbid hyperactivity, 95 patients(60.5%) had obsession, 55 patiens(35.0%) had self destructiveness, 46 patients(29.3%) had impulsivity, and 35 patients(22.3%) had enuresis. Age of onset had a significant positive correlation with age, duration, and the global severity of obsession；and a negative correlation with the severity of hyperactivity. Hyperactivity had a significant positive correlation with impulsivity, obsession-compulsion, enuresis, and self destructiveness. Obsession-compulsion had a significant positive correlation with hyperactivity, sleep problems, and self destructiveness. Conclusion：These data suggest that clinical characteristcs and behavioral comorbidity of patients with Tourette’ disorder in this study are similar to previous research findings in Korea and other contries. The younger the age of onset was, the more severe hyperactivity was, and the less severe obsession-compulsion was. And severity of hyperactivity had a positive correlation with the severity of obsession-compulsion, impulsivity, enuresis, and self destructiveness.

• Clinical and Experimental Pediatrics
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• v.51 no.12
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• pp.1324-1328
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• 2008

Purpose : Attention deficit hyperactivity disorder (ADHD) is a syndrome characterized by inattention, impulsive disruptive behavior, impaired concentration, and motor restlessness. This study examined the relationships among electroencephalographic (EEG) findings, stimulant use, and seizure occurrence in children with ADHD. Methods : We retrospectively studied 308 children with ADHD who visited the neuropsychiatric clinic of our hospital from January 2001 to December 2005. We retrospectively analyzed age distribution, etiology, abnormal EEG findings, and use of CNS stimulants. Among these children, brain waves was recorded in 84 patients. Results : Eighty-four children (72 males, 85.7%, 9.3 years mean age; 12 females, 14.3%, 8.0 years mean age) with ADHD had electroencephalograms (EEGs) performed at our institute. Nineteen patients (22.6%) demonstrated epileptiform abnormalities, and 65 (77.4%) demonstrated normal EEGs. Stimulant therapy was applied to 59 of 84 patients (70.2%). Seizures occurred in 1 of 65 patients with a normal EEG (incidence, 1.5%) and 3 of 19 treated patients with epileptiform EEGs (incidence, 15.7%). Conclusion : These data suggest that patients with normal EEGs have minor risk for seizure. In contrast, patients with epileptiform EEGs have higher risk for seizure than patients with normal EEGs.

• Journal of The Korean Association For Science Education
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• v.43 no.3
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• pp.295-306
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• 2023

In this study, we explored science teachers' perceptions of adaptive practice in terms of importance and practice. For this purpose, an adaptive practice questionnaire was developed targeting secondary science teachers, and the responses of 128 science teachers were analyzed. The results of this study were as follows: First, the science teachers responded that all 17 items regarding adaptive practice were important. In particular, items related to 'addition of examples', 'adjustment of the level/range of concepts', and 'encouragement of student participation' showed high importance and performance levels. Second, the results of the IPA concerning adaptive practice showed that the items needing intensive improvement due to high importance but low performance were 'encouraging students' self-directed learning' and 'monitoring and responding to individual differences'. The science teachers identified a lack of time and uniform curriculum as the reasons for the low level of practice despite the high importance of these items. Third, regarding the IPA of the adaptive practice items, the items located in the fourth area, an excessive area, concerned 'pace control', 'modifying activities', and 'metaphor use'. More specifically, considering that 'metaphor use' was the only item with a higher level of performance than importance, it is necessary to reconsider whether problems are caused by excessive use. Fourth, analyzing the responses regarding the reasons for the difference in importance and performance revealed that the factors related to teachers included teachers' lack of knowledge or ability, and the tendency to implement as planned. As for student factors, an excessive number of students, differences in the levels of students, and a tendency to prefer classes centered on entrance exams were identified. As environmental factors, a uniform curriculum, conditions for experiments, evaluation systems, and external demands were mentioned. Finally, the implications of the results of this study for science education were discussed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.2
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• pp.226-233
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• 2015

The purpose of this study was to evaluate salt-related dietary attitudes, behaviors, and nutrition knowledge according to urinary salt signal of university students. Based on urinary salt signal, we classified subjects into an "adequate Na intake (ANI)" group (n=52) (salt ${\leq}6g$) and "excess Na intake (ENI)" group (n=66) (salt >6 g). Subjects were asked about general characteristics, lifestyle, salt-related dietary attitudes, behaviors, and nutritional knowledge using questionnaire. The ENI group had more subjects who were drinkers (P<0.05) compared to the ANI group. The ENI group (33.45) showed a significantly lower score in terms of salt-related dietary attitudes compared to the ANI group (35.50) (P<0.05). There was no significant difference in the total score of salt-related dietary behavior between the groups. The score of nutrition knowledge was significantly higher in the ANI (9.77) group than in the ENI (8.82) group (P<0.05). The correlation analysis indicated that the urinary salt signal had a negative correlation with the salt-related dietary attitude score after adjustments for age, sex, and body mass index (r=-0.2100, P<0.05). These results support the validity of using the urinary salt signal to simplify estimation of sodium intake.

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.1
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• pp.77-94
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• 2021

The purpose of this study was to investigate the three-dimensional characteristics of mesiodens using Cone-beam Computed Tomography(CBCT) and analyze the factors affecting complications and anesthetic methods of extraction. This study evaluated 602 mesiodens of 452 patients who underwent extraction of mesiodens at the department of Pediatric Dentistry in Seoul National University Dental Hospital between 2017 and 2019. The ratio of mesiodens patients over total patient per year was gradually increased over the past 20 years. Mesiodens with labio-palatally horizontal direction while root directing labial were the most common among the mesiodens with horizontal direction. Mesiodens were the most common at the cervical side of the adjacent teeth(37.0%) and mesiodens located in the near-palatal side were observed about 3.83 times higher than the far-palatal side. Most of the mesiodens(82.1%) were in contact with adjacent permanent teeth on all three sides of the CBCT and 46.2% of mesiodens had curved roots. The patient's age, vertical position, presence of complications, and proximity showed a significant difference in the selection of general anesthesia among anesthetic methods. The direction and vertical position of mesiodens had a significant effect on complications. These results provide a better understanding of mesiodens for establishing an accurate diagnosis and treatment plan.

• Journal of Korean Society of Disaster and Security
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• v.11 no.2
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• pp.29-35
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• 2018

This study is an experimental comparison on the fact that the sinusoidal load, which has been used so far in the laboratory cyclic test, which is an important part of the liquefaction triggering study, is somewhat different from the phenomenon that causes the soil liquefaction during the earthquake loading. To this end, this study proposes a new type of combined sinusoidal load and compares it with experimental results to load the conventional sine wave. In the comparison, the shaking table tests were carried out and the sample in the tests was remolded with the relative density of 40%, which is a condition where liquefaction is easy to occur. Firstly, the conventional cyclic test was carried out under the condition that with the amplitude of sine wave was 0.3 g. Additionally, 3 types of tests were performed using the combination loads made up with 0.03 g sinusoidal load and 0.3g sinusoidal load. At that time, the loading time for the first sinusoidal load were changed with 5 seconds, 10 seconds, and 15 seconds. As a result, the test with the conventional sine wave and the test with the first sinusoidal loading for 5 seconds showed that the change of the pore water pressure gradually increased. But in the tests with the combined sinusoidal load which changed the first sinusoidal loading time with 10 and 15 seconds, it was found that the pore water pressure suddenly rose at a certain instant and liquefaction occurs. From the experimental comparison, it is judged that it is appropriate that the time of the first sine wave is over 10 seconds at the proposed combined load for the soil condition with relative density 40%.