• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.7
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• pp.591-597
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• 2017

This study is to develop a vehicle Integrated Dynamics Control System(IDCB) that can stabilize the lateral dynamics and maintain steerability. To accomplish this task, an eight degree of freedom vehicle model and a nonlinear observer are designed. The IDCB independently controls the brake systems of four wheels with a fuzzy logic control and a sliding model control. The result shows that the nonlinear observer produced satisfactory results. IDCB tracked the reference yaw rate and reduced the body slip angle under all tested conditions. It indicates that the IDCB enhanced lateral stability and preserved steerability.

• Childhood Kidney Diseases
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• v.15 no.1
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• pp.58-65
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• 2011

Purpose: Some hormonal and electrolyte abnormalities have been reported in pediatric patients with urinary tract infection (UTI). This study aimed to investigate the relationships between the imbalance of electrolytes and the severity of infection and associated urologic anomalies in children with febrile UTI. Methods: We retrospectively reviewed 267 patients with febrile UTI who were admitted to Korea University Guro Hospital during the period from January, 2007 until February, 2010. According to the presence of hyponatremia or hyperkalemia, clinical parameters and associated renal anomalies, such as hydronephrosis, cortical defects and vesicoureteral reflux, were compared. Results: 42.7% of all patients had decreased concentration of serum sodium. In patients with decreased concentration of serum sodium, cortical defects were significantly increased compared to normal patients (40.4% vs. 14.4%, P <0.05). White blood cell (WBC) counts ($15,721{\pm}6,553/uL$ vs. $12,885{\pm}5,367/uL$, P <0.05), C-reactive protein (CRP) ($61.8{\pm}56.1$ mg/L, vs. $29.9{\pm}39.8$ mg/L, P <0.05), and erythrocyte sedimentation rate (ESR) ($43.9{\pm}34.3$ mm/hr vs. $27.4{\pm}26.8$ mm/hr, P <0.05) in peripheral blood showed significant increases in the group with decreased concentration of serum sodium. Duration of fever, presence of gastrointestinal symptom, the incidence of hydronephrosis and vesicoureteral reflux did not differ between the two groups. None of the patients had significant hyperkalemia. Conclusion : We suggest that decreased concentration of serum sodium in febrile UTI might be a helpful marker for leukocytosis and increased CRP and ESR in peripheral blood, and acute pyelonephritis.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.3
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• pp.174-182
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• 2008

As the survey and the analysis the research can offer the characteristic methods for regeneration in the city of Busan. To figure out the functional regions of city center the research has analyzed 15 Dongs in city center and 12 Dongs in sub centers to find out the donut phenomenon and the regeneration of city center. The survey has chosen 22 variation factors using factor analysis. Major factors in each year are shown 4 factors, presenting 80.4% of the accumulated explanation rate. These factors explain residental centered, commercial centered, management centered, and development centered factor. The donut phenomenon emerges in the city centers as a residential function, and the phenomenon occurs in the sub centers as commercial or managerial function. So it is necessary to plan the regeneration of the total city center owing to the total donut phenomenon regarding the functions. And the methods to regenerate city centers should be established according to the various regional characterizations.

• The Journal of the Korea Contents Association
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• v.8 no.6
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• pp.269-280
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• 2008

This study was intended to reconsider the work song in the modem children's life and to search its utilization plan. For it, folk songs were collected from internet website("Search for Korean Forlk song") and books, then the proper work songs suitable for the purpose of the study were selected. Selected work songs were reformed in order to utilize in a daily life including infant daily life and play in the home with mother. That is, the work song was presented to be utilized while changing a diaper, massaging, taking a rest, letting children take a nap, whispering in the children's ears, taking a bath, exercising after the bath, doing a body play, and facing each other.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.1-9
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• 2010

In this paper, advanced evacuation analysis simulation on a passenger ship is performed. Velocity based model has been implemented and used to calculate the movement of the individual passengers under the evacuation situation. The age and gender of each passenger are considered as the factors of walking speed. Flocking algorithm is applied for the passenger's group behavior. Penalty walking velocity is introduced to avoid collision between the passengers and obstacles, and to prevent the position overlap among passengers. Application of flocking algorithm and penalty walking velocity to evacuation simulation is verified through implementation of the 11 test problems in IMO (International Maritime Organization) MSC (Maritime Safety Committee) Circulation 1238.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.11 no.1
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• pp.91-99
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• 2000

Objectives：Present study developed the computerized ADHD Diagnostic System(ADS) in order to diagnose ADHD and evaluate treatment effect of it, and conducted a standardization study for ADS. Methods：The normative group was composed of 847 children and adolescents between the age of 5 and 15(boy 429, girl 418) living in the areas of Seoul, Kyunggi-do, and Kangwon-do. 30 ADHD children with age ranged 7 to 9 years were participated present study to evaluate the validity of ADS. To establish the norms for diagnosing ADHD, the means and standard deviations of normative group were used to calculate T-scores for each age group. Results：The reliability coefficient of ADS(Cronbach's ${\alpha}$) was .85. There were significant differences in the measures of ADS except commission error between the normal and the ADHD groups. Three factors were extracted through factor analysis of ADS, which were labelled 'inattention', 'slow information processing' and 'impulsivity'. Discriminant analysis showed that ADS significantly discriminate the normal and the ADHD groups. Percentage of correct classification by ADS variables was 96.7%. Conclusion：These results put together strongly support the reliability and validity of ADS as a diagnostic instrument for ADHD.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10c
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• pp.27-29
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• 2000

마이크로 프로세서의 동작 속도와 디스크 액세스 속도의 성능 차이는 컴퓨터 시스템의 성능을 제한하는 중요한 요인 주의 하나로 지적되고 있다. 이러한 격차를 줄이는 기술로 디스크 캐쉬의 운영이 연구되어 왔고 디스크 캐쉬 성능 개선 방법으로 선인출이 널리 연구되어 왔다. 본 논문에서는 디스크 드라이브 상에 구현된 캐쉬에서 디스크 요청에 대한 성격적 유형을 힌트로 이용한 선인출 적용방법을 제안하고, 제안된 방법의 유효성은 시뮬레이션 방식으로 입증하였으며 적응적으로 변경된 선인출 적용 방법이 성능의 개선을 이룰 수 있음을 보였다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.9 no.4
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• pp.509-517
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• 1985

작업 공간내에서 원하는 속도와 가속도로, 주어진 경로를 따라 이동하는 k차원 좌표계를 구성하고, 메니퓰레이터의 운동 방정식을 이 좌표계로 변환하여 운동 경로에 대한 선형화 식을 구하였다. 이 시스템의 입력을 변위와 속도의 함수로 정의한 후 안정성을 고려하여 이득을 결정하여 비례-적분제어 시스템을 구성하였다. 이와 같이 구한 적응 제어 알고리즘은 메니퓰레이터의 동적 특성에 대한 정확한 지식을 요하지 않고 또 계산이 간단하여 실시간 응용이 가능하다. 예로서 3차원 공간상의 반경 10cm의 원궤도에 적용하였을 때 최대 오차는 대략 1mm이었으며 상황 변화에 무감각함을 보였다.

• Journal of the Korea Society for Simulation
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• v.28 no.3
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• pp.83-89
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• 2019

This research describes quantitative effects of initial dispersion conditions upon the dispersion randomness of Magnus rotor bomblets. Ratios of the missile spin rate to the missile velocity, a, flight path angles, ${\gamma}$ and altitudes, h, were changed to investigate their effects on dispersion randomness. Dispersion was analyzed through calculation of 6 degree of freedom motion equation with aerodynamic coefficients from wind tunnel experiments. In order to analyze the randomness, regression analysis is adopted to calculate the coefficient of determination. The optimized ratio of the missile spin rate to the missile velocity and flight path angle were obtained and the dispersion altitudes had more effect on the dispersion diameter and had less effect on dispersion than other parameters.

• Journal of Communication Design
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• v.38
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• pp.80-90
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• 2012

The purpose of this study is to determine the differences in eye-tracking, which is one of the emotional reactions of the autonomic nervous system, against various experimental stimuli that vary in terms of the movement attributes of graphic image. This experiment conducted an analysis of variance of the movement factors(n) in each movement attribute(speed, horizontality movement, verticality movement, diagonal movement). Dependent variables were the fixation starting time, the fixation dwell time, the whole fixation time from stimulus appearance, and the eye-tracking length. The result of eye-tracking against movement speed showed nonsignificant differences for each movement attribute. In the horizontality movement, the → movement was higher than the ← movement. In the verticality movement, the ↑ movement was higher than the ↓ movement. In the diagonal movement, there was not significant differences for each movement attributes.