• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.260-270
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• 1998

The field tests were performed to suggest the rational method for stability evaluation of soft clay. The behavior of settlement-displacement obtained by field monitoring system was to compare and analyze the results of the observationed method, and to investigate the complex behavior of soft clay with filling height. The results of this study are summarized as follows. 1. The horizontal displacement was suddenly increased when physical properties of soft clay showed maximum values and the part of the turning point. The values of these properties were available to the fundamental data for stability evaluation. The shear deformation appeared that difference of the horizontal displacement was maximum values. 2. Although the stability of embankment by step filling showed the unstable part over the failure standard line, the embankment was confirmed stable. So the evaluation of the stability of embankment is reasonable to use the inclination of curve than failure standard line. 3. The horizontal displacement and relative settlement were increased as same ratio at improvement ground. Estimation of shear deformation using Terzaghi's modified bearing capacity should consider the relations of embankment load and undrained shear strength at nonimprovement ground, and minimum safety factor is recommended to use larger than 1.2. 4. Excess pore water pressure was increased with increasing of filling height and decreased with maintain the filling height. The embankment was unstable when filling height was exceed the evaluation standard line, and the behavior of excess pore water pressure and horizontal displacement could use as a standard of judgement of the filling velocity control because their behavior were agree with each other.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4C
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• pp.247-254
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• 2006

Online testing method is one of the numerical experiment methods using experimental information for a numerical analysis directly. The method has an advantage in that analysis can be conducted without using an idealized mechanical model, because mechanical properties are updated from element test for a numerical analysis in real time. The online testing method has mainly been used for the geotechnical seismic engineering, whose major target is sand. A testing method that may be applied to a consolidation problem has recently been developed and laboratory and field verifications have been tried. Although related research thus far has mainly used a method to update average reaction for a numerical analysis by positioning an element tests at the center of a consolidation layer, a weakness that accuracy of the analysis can be impaired as the thickness of the consolidation layer becomes more thicker has been pointed out regarding the method. To clarify the effectiveness and possible analysis scope of the online testing method in relation to the consolidation problem, we need to review the results by applying experiment conditions that may completely exclude such a factor. This research reviewed the results of the online consolidation test in terms of reproduction of the consolidation settlement and the dissipation of excess pore water pressure of a clay specimen by comparing the results of an online consolidation test and a separated-type consolidation test carried out under the same conditions. As a result, the online consolidation test reproduced the change of compressibility according effective stress of clay without a huge contradiction. In terms of the dissipation rate of excess pore water pressure, however, the online consolidation test was a little faster. In conclusion, experiment procedure needs to improve in a direction that hydraulic conductivity can be updated in real time so as to more precisely predict the dissipation of excess pore water pressure. Further research or improvement should be carried out with regard to the consolidation settlement after the end of the dissipation of excess pore water pressure.

• Korean Journal of Psychosomatic Medicine
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• v.13 no.2
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• pp.102-111
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• 2005

Objective : The purpose of this study was to investigate the quality of life and it's related factors in caregivers of attention deficit hyperactivity disorder patients. Methods : The subjects were 38 attention deficit hyperactivity disorder patients' caregivers(mean age : $37.5{\pm}6.5$, 38 women). Patients were diagnosed with DSM-IV-TR ADHD criteria. Korean version of WHOQOL-BREF(World Health Organization Quality of Life assessment instrument Abbreviated Version) was used for assessment. Results : 1) No significant differences were found in the score of WHOQOL-BREF, overall QOL, physical health domain, psychological domain, social relationships domain and environmental domain between caregiver and control group. 2) The score of Activity of daily living facet$(3.0{\pm}0.7\;vs.\;3.6{\pm}0.7)(p=0.008)$ and self-esteem facet $(2.8{\pm}0.7\;vs.\;3.3{\pm}0.7)(p=0.049)$ were significantly decreased in caregivers of ADHD. 3) Total score of WHOQOL-BREF(r=0.437, p=0.007) and physical health domain(r=0.370, p=0.024) were correlated with caregiver's educational age. 4) In the psychological domain, the score of self-esteem facet(r=-0.337, p=0.039) and thinking, learning, memory & concentration facet(r=-.341, p=0.036) were decreased with caregiver's age. 5) The score of environmental domain were significantly increased with caregiver's educational age (r=0.482, p=0.003), but decreased with patient's age(r=0.328, p=0.044). Conclusion : Although the quality of life in caregivers of ADHD patient had not significantly decreased than control, the quality of lift were positively correlated with educational age of caregives, and negatively correlated with chronological age of caregivers and children. Above results suggest that physicians should consider integrated approaches for caregiver's subjective quality of life in the management of ADHD.

• Journal of Yeungnam Medical Science
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• v.14 no.1
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• pp.123-136
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• 1997

The purpose of this study was to examine the reliability and validity of a Korean form of Childhood Attention Problem(CAP) scale. CAP were administered to 98 normal elementary school students as control group and 98 attention deficit hyperactivity disorder patients. Male students showed high scores than female students in both subscale and total scores, but not statistically significant. There were no significant difference in CAP scale between male students and female students in attention deficit hyperactivity disorder patients. In the reliability test, the test-retest reliability coefficient was highly satisfactory and that of inattention subscale was 0.83, impulsivity subscale was 0.70 and total score was 0.82. In the reliability test by internal consistency, the Cronbach $\alpha$ coefficient was highly satisfactory and that of inattention subscale was 0.91, overactivity subscale was 0.89(p<0.05). The concurrent validity between CAP scale and ADDES-BV scale was 0.85 in attention deficit hyperactivity disorder patient group and 0.73 in normal control group(p<0.05). In discriminant validity test between attention deficit hyperactivity disorder patient group and normal control group, the patient group showed higher score(p<0.05). The total discriminant capacity of the patient group in CAP was 93.4%. In this point of view, CAP scale showed high reliability and validity in applying to Korean subjects and was proved to be the good and simple screening test tool for attention deficit hyperactivity disorder research and can help many young patient to treat early.

• Journal of Nutrition and Health
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• v.43 no.5
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• pp.533-542
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• 2010

The objective of this study is to provide basic information and policy implications needed to balance the supply and demand for dietitian by projecting supply and demand for dietitian. The data from the Ministry of Health Welfare and Family on the number of licensed nutritionist, resident registration data of the Ministry of Public Administration and Security, and health insurance qualification data of the National Health Insurance Corporation were used to examine the current status of supply. To project the supply of nutritionist workforce, the in-out moves method and demographic method were used. The ratios of nutritionist to population and GDP, and that of other countries were applied as the demand projection method. According to the study results, the projection on the imbalance of supply and demand for dietitian by year 2021 differs depending on the method used. First, according to the results based on age-adjusted population ratio, there is an oversupply of 1,643 dietitians in year 2010, and 2,076 dietitians in year 2020. Second, although the projection on the imbalance of the supply and demand for dietitian differs depending on whether the GDD is calculated in won(￦) or dollar($). it is expected that there will be an oversupply in general. Third, as to the scenario using the nutritionist ratio in foreign countries, the oversupply of dietitian is likely in Korea, under any scenario, when comparing the nutritionist supply projection with the demand projection based on the nutritionist ratio in the United States. However, the projection of the supply and demand varies in each scenario when the European nutritionist ratio is applied. Under European 'scenario 1', an oversupply is expected, whereas under 'scenario 2', a shortage of supply is expected. A careful approach is required in interpreting the supply and demand projection using criteria of other countries, because dietitian assumes different roles and functions in each country. Although a slight oversupply of nutritionist workforce is projected, it does not cause a major problem as the demand for diet therapy is expected to rise due to aging and the increase of chronic diseases, and as the demand for clinical dietitians in hospitals increases. Accordingly, the demand for dietitians will rise and, in this context, the oversupply of nutritionist will not incur much problem. However, the nutritionist qualification is much too open in Korea, and this has a negative effect on the quality of the nutritionist workforce. Therefore, it is important that the nutritionist qualifications and requirements are reinforced in the future, enhance the quality level of the nutritionist supply, and maintain the balance between the supply and demand.

• Journal of KIISE:Software and Applications
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• v.37 no.8
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• pp.647-652
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• 2010

Esterel is an imperative synchronous language well-adapted to control-intensive systems. When an Esterel program is translated to a circuit, the synchronizer of a parallel statement may be executed more than once in a clock; the synchronizer is called schizophrenic. Existing compilers cure the problems of schizophrenic parallel synchronizers using logic duplications. This paper proposes the conditions under which a synchronizer causes no problem in circuits when it is executed more than once in a clock. In addition we design a detection algorithm based on those conditions. Our algorithm detects schizophrenic parallel synchronizers that have to be duplicated in Esterel source codes so that compilers can save the size of synthesized circuits

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.189-189
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• 2022

물 공급 시설의 효율적이고 안정적인 운영을 위한 운영 계획의 수립 및 검증을 위해서는 장기간의 유입량 자료가 필요하다. 하지만, 현실적으로 얻을 수 있는 실측 자료는 제한적이며, 유입량이 부족하여 댐 운영에 영향을 미치는 자료는 더욱 적을 수밖에 없다. 이를 개선하고자 장기간의 모의 유입량을 생성해 운영 계획을 수립하는 방법이 종종 사용되지만, 실측 자료를 기반으로 모의하기 때문에 이 역시 가뭄의 빈도가 낮아, 장기 가뭄이나 짧은 간격으로 가뭄이 발생할 시 안정적인 운영이 어렵다. 본 연구에서는 장기 가뭄 발생 시에도 안정적인 물 공급이 가능한 운영 계획 수립을 위해 가뭄 빈도를 증가시킨 유입량 모의 기법을 제안하고자 한다. 제안하는 모의 기법은 최근 머신러닝에서 사용되는 SMOTE 알고리즘을 기반으로 한다. SMOTE 알고리즘은 데이터의 불균형을 처리하기 위한 오버 샘플링 기법으로, 소수 그룹을 단순 복제하지 않고 새로운 복제본을 생성해 과적합의 위험이 적으며, 원자료의 정보가 손실되지 않는 장점이 있다. 본 연구에서는 미국 캘리포니아주에 위치한 Folsom 댐을 대상으로 고빈도 가뭄 유입량을 모의했으며, 고빈도 가뭄 유입량을 사용한 운영 계획을 수립하였다. Folsom 댐의 과거 관측 유입량 자료를 기반으로 고빈도 가뭄 유입량을 사용한 운영 계획과 일반적인 가뭄 빈도의 유입량을 사용한 운영 계획을 적용했을 때 발생하는 공급 부족량과 과잉 방류량의 차이를 비교해 고빈도 가뭄 유입량의 사용이 물 공급 시설의 안정적인 운영에 끼치는 영향을 확인하고자 한다.

• Proceedings of the Korean Geotechical Society Conference
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• 1997.10a
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• pp.81-88
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• 1997

현재 국내외에서 해안가에 수심이 낮은 지역을 중심으로 대규모 매립공사를 수행하여 주택단지, 항만시설, 공업단지 및 공항부지 등으로 사용하고 있다. 매립재를 양질의 모래로 사용하는 경우 매립방법에 따라 매립토의 조밀정도는 다르나 어떠한 경우든 상당히 느슨하거나 중간정도 느슨한 상태로 존재한다. 이런한 느슨한 사질토는 지진 시 액상화 현상에 민감하고, 낮은 지지력 및 큰 즉시침하를 야기시킨다. 따라서 매립된 느슨한 사질토는 향후 시설될 구조물의 중요도에 따라 개량할 필요가 있다. 본 현장의 준설 매립된 사질토의 지반 개량에 적용된 동다짐의 시험시공중 pounder에 accelerometer를 설치하고 적외선 beam을 이용, 충격시의 pounder의 deccleration과 impact velocity를 측정하였다. 여기에서는 이들 실측치를 근거로 중량물체(pounder)의 동적 거동 및 충격시 과잉간극수압 변화를 살펴보았다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.145-145
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• 2003

자성유체는 암 치료와 질병진단 등과 같은 다양한 분야에서 유용한 응용의 가능성을 갖는다 [1]. 생리적 염도인 중성 pH에서 생체조직과 잘 교합하고, 높은 안정성을 가지는 자성유체는 자성 나노입자 표면에 화학적으로 흡착된 계면활성제 종류에 따라 달라진다 [2]. 본 실험에서는 화학적 공침법을 이용하여 Fe$^{2+}$와 Fe$^{3+}$ 의 몰비가 1:2인 수용액에 pH 12 이상의 과잉 알칼리(NH$_4$OH 12ml)를 첨가시켜 마그네타이트 콜로이드 용액을 제조하였다. 광감제로는 hematoporphyin을 사용하였으며 투입량은 1$\times$$10^{-3}$mol/l 였다. 또한 1차 및 2차 계면활성제로는 decanoic acid와 starch, citric acid, oleic acid 등이 각각 사용되었다. 각 계면활성제가 코팅된 자성미립자의 특성을 조사하기 위해 동결 건조 후 VSM, FT-IR 및 TEM 분석을 수행하여 자기적 특성과 코팅표면의 결합구조 및 미시적 구조를 분석하였다. 그리고, 각각의 계면활성제가 코팅된 자성유체의 독성을 조사하기 위해 rat를 이용한 생체실험이 병행되었다.

• Polymer Science and Technology
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• v.9 no.1
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• pp.17-23
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• 1998

지금까지 다양한 종류의 촉매 시스템에 의한 폴리올레핀 제조법에 관하여 알아보았다. 특히, 기존의 불균일계 착체 전이 금속 촉매 시스템 및 균일계 촉매 시스템에 의한 폴리올레핀 합성법과 비교하여 활성도 및 입체 규칙성 측면에서 최근 세계적인 '핫 잇슈'가 되고 있는 메탈로센 촉매 시스템을 이용한 폴리올레핀 제조법에 대하여 검토하였다. 이들에 대한 상세한 반응기구 및 반응 속도론(kinetics)에 대한 사항은 생략하였다. 이들에 대한 상세한 설명들은 여러 문헌에 잘 소개되어 있으며, 메탈로센 촉매 제조를 위한 다양한 리간드 합성법도 문헌에 잘 소개되어 있다. 이미 설명한 폴리올레핀 신합성법에 사용되는 메탈로센 촉매 및 비메탈로센계 촉매 이외에도 최근 크롬계 촉매 역시 올레핀 중합에 긴요하게 사용될 수 있을 것으로 판단된다. 이러한 관점에서, 현재 국내에서 폴리올레핀 공급과잉 현상은 새로운 기술에 의한 각종 그레이드(grade)의 특화만이 문제점 해결의 지름길이 될 것이라 판단된다.