• Journal of Nutrition and Health
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• 제31권9호
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• pp.1422-1432
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• 1998

This study investigated the nutritional status of 32 CAPD patients. Their weight, height, triceps, mid arm circumference were measured and their dietary intake and the blood profiles were evaluated. They were 56.0${\pm}$11.8 years old. Their intake of energy and protein were 78% and 93% of RDA respectively. The energy from dextrose was 376.1${\pm}$83.2kcal. The men's and women's intake of protein was 84.6% and 102.1% of RDA respectively, According to the distribution of BMI, 23.5% of the men and 6.1% of the women were underweight and 5.9% of the men and 20% of the women were overweight. The serum albumin levels of the men and women were 3.30 and 3.71g/41 respectively. However, the average amount of serum ferritin, as a whole, comes within the normal range, which shows that stored iron was not decreased and that their anemia was not caused by iron deficiency. The subjects were divided into three groups according to the level of albumin, and their intakes of nutrients were compared with one another, The group with the high level of albumin showed that energy and protein intake was significantly larger and that BMI was also significantly higher than the other groups. There was a positive correlation between BMI and energy intake. Serum total protein had a positive correlation to energy intake ; hematocrit, to carbohydrate intake. BMI had a positive correlation to energy intake. A relative magnitude of factors affecting albumin level was analyzed by Stepwise multiple regression analysis. Overall results about relative influence of independent variables to dependent variable(albumin) indicated that the blood total protein(p <0.0001) was the most significantly correlated with serum albumin level in all subjects,1311owe4 by creatinine and total cholesterol. (Korean J Nutrition 31(9) : 1422-1432, 1998)

• 응용통계연구
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• 제31권5호
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• pp.621-636
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• 2018

정보적 표본설계 기법을 적용하여 무응답의 영향을 줄이기 위한 연구가 진행되고 있다. 특히 초모집단모형(super population model)에 포함된 오차의 분포가 정규분포를 따르고 응답률이 지수함수를 따를 때 지수형 응답률 정보를 모수추정에 사용함으로써 추정의 정확성이 향상되는 것으로 알려져 있다. 최근 Chung과 Shin (2017)은 정보적 표본설계의 가중치를 구하기 위해 세부 층을 등간격으로 나누는 방법을 고려하였으며 세부 층의 개수가 추정의 정확성에 영향을 주는 것을 확인하였다. 이에 본 연구에서는 주어진 표본 규모에 따른 최적의 세부 층 개수와 최적의 층 경계를 구하기 위해 등간격, 분위수, LH 알고리즘을 이용하여 층을 나누는 방법을 살펴보았으며 모의실험을 통하여 각 방법의 결과를 비교하였다. 또한 다양한 형태의 보조변수 분포를 이용하여 실무에서 사용할 수 있는 세부 층 경계와 세부 층 개수를 정하는 기준을 제안하였다.

• Transactions on Control, Automation and Systems Engineering
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• 제3권3호
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• pp.181-189
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• 2001

The software components of embedded control systems get extremely complex as they are designed into distributed systems get extremely complex as they are designed into distributed systems consisting of a large number of inexpensive microcontrollers interconnected by low-bandwidth real-time networks such as the controller area network (CAN). While recently emerging middleware technologies such as CORBA and DCOM address the complexity of distributed programming, they cannot be directly applied to distributed control system design due to their excessive resource demand and inadequate communication models. In this paper, we propose a CORBA-based middleware design for CAN-based distributed embedded control systems. Our design goal is to minimize its resource need and make it support group communication without losing the IDL (interface definition language) level compliance to the OMG standards. To achieve this, we develop a transport protocol on the CAN and a group communication scheme based on the well-known publisher/subscriber model. The protocol effectively realizes subject-based addressing and supports anonymous publisher/subscriber communication. We also customize the method invocation and message passing protocol, referred to as the general inter-ORB protocol (GIOP), of CORBA so that CORBA method invocations are efficiently serviced on a low-bandwidth network such as the CAN. This customization includes packed data encoding and variable-length integer encoding for compact representation of IDL data types. We have implemented our CORBA-based middleware on the mArx real-time operating system we have developed at Seoul National University. Our experiments clearly demonstrate that it is feasible to use CORBA in developing distributed embedded control systems possessing severe resource limitations. Our design clearly demonstrates that it is feasible to use a CORBA-based middleware in developing distributed embedded systems on real-time networks possessing severe resource limitations.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1983-1989
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• 2005

Industrial robots are powerful, extremely accurate multi-jointed systems, but they are heavy and highly rigid because of their mechanical structure and motorization. Therefore, sharing the robot working space with its environment is problematic. A novel pneumatic artificial muscle actuator (PAM actuator) has been regarded during the recent decades as an interesting alternative to hydraulic and electric actuators. Its main advantages are high strength and high power/weight ratio, low cost, compactness, ease of maintenance, cleanliness, readily available and cheap power source, inherent safety and mobility assistance to humans performing tasks. The PAM is undoubtedly the most promising artificial muscle for the actuation of new types of industrial robots such as Rubber Actuator and PAM manipulators. However, some limitations still exist, such as the air compressibility and the lack of damping ability of the actuator bring the dynamic delay of the pressure response and cause the oscillatory motion. In addition, the nonlinearities in the PAM manipulator still limit the controllability. Therefore, it is not easy to realize motion with high accuracy and high speed and with respect to various external inertia loads in order to realize a human-friendly therapy robot To overcome these problems a novel controller, which harmonizes a phase plane switching control method with conventional PID controller and the adaptabilities of neural network, is newly proposed. In order to realize satisfactory control performance a variable damper - Magneto-Rheological Brake (MRB) is equipped to the joint of the manipulator. Superb mixture of conventional PID controller and a phase plane switching control using neural network brings us a novel controller. This proposed controller is appropriate for a kind of plants with nonlinearity uncertainties and disturbances. The experiments were carried out in practical PAM manipulator and the effectiveness of the proposed control algorithm was demonstrated through experiments, which had proved that the stability of the manipulator can be improved greatly in a high gain control by using MRB with phase plane switching control using neural network and without regard for the changes of external inertia loads.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제20권3호
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• pp.146-151
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• 2009

Objectives : We conducted this study to investigate the relationship between sleep duration and body mass index (BMI), in Korean children. Methods : We performed a cross-sectional analysis of data collected on 3,639 boys and girls (aged 7-12) in Daegu, Korea. The data included each child's age, sex, weight, height, extracurricular activities, bedtime, wake-up time, sleep latency, total sleep duration, parents' occupations, and parents' educational levels. The relationship between sleep duration and each variable was examined via analysis of variance (ANOVA). Results : The analysis showed an association between short sleep duration and high BMI. Boys showed a graded inverse relationship between sleep duration and BMI. However, there was no significant corresponding result for girls. In the total sample, hours of computer use, time when the computer was turned off, time when the television was turned off, mother's bedtime, and hours of extracurricular activity were associated with longer sleep duration. No association was found between sleep duration and hours of watching television, child's wake-up time, or educational level of the parents. Conclusion : The results of this study show an inverse relationship between a child's sleep duration and BMI；thus, children with shorter sleep duration tend to have higher BMIs.

• 한국해양공학회지
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• 제24권6호
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• pp.76-80
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• 2010

Oil hydraulic piston pumps are being extensively used around the world, because of their simple design, light weight, effective cost, etc. An oil hydraulic pump is likely to have the serious problems of high leakage, friction, and low energy efficiency after a long period of use. In an oil hydraulic piston pump, the clearance between the valve block and piston plays an important role for volumetric and overall efficiency. In this study, the wear property of the SACM645 material with DLC coating used for a hydraulic piston pump was determined by experimentation with variable heat treatment. To investigate the effect according to the piston surface condition, five different types of specimens were prepared. The maximum tensile strengths of the QT and QT Nitration specimens had similar values of about 800 MPa, but the strains indicated a big difference. In a wear test, the wear characteristic of the DLC coating specimen was shown to be excellent. The QT, QT + IH, QT + Nitration, and matirx specimen showed similar wear characteristics. In the case of a dry condition without oil, the DLC coating specimen had good wear resistance, with no wear shown.

• KIEAE Journal
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• 제13권5호
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• pp.67-77
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• 2013

Based on the increasing demand for a solution to reduce thermal load, extensive green roofs have great opportunity for application to existing roofs due to their light-weight and easy maintenance. The present study delivers data regarding thermal behavior and heat reduction potential in relation to vegetation coverage between green roof types. 1) In the hottest hour in a day, green roofs showed considerable potential to mitigate heat load in roof environments, which can be up to $10^{\circ}C$ difference. 2) Compared to conventional cement roofs, the extensive green roofs only have a slight potential to cool the air over green roofs. By statistical analysis of linear regression, green coverage has little to do with the reduction of air temperature; the cooling effect was proven only in nighttime. 3) Green roofs act as an insulating roof membrane, the inner substrate of green roofs remained cooler than cement roof surfaces in the daytime, but in the nighttime the green roofs generally were warmer than the cement roof surfaces. 4) The variable of vegetation coverage resulted in no significant difference in thermal behavior in the air, but had the greatest effect in keeping the substrate cool in the daytime. The high vegetation coverage also hindered the rapid cooling of the substrate in the nighttime, and therefore was warmer than other measured temperatures. In order to draw a clear conclusion to combat urban heat island effect with extensive green roofs, the experiment needs to be applied on a larger scale.

• Journal of the Korean Data and Information Science Society
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• 제27권3호
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• pp.741-747
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• 2016

본 연구에서는 국가단위 개체모형을 이용하여 일반농가 한우의 도체중, 등심단면적, 등지방두께, 국내지방도에 대한 유전력를 추정하고 이를 국가단위 종모우 선발용 후대검정우 집단의 유전력과 비교하여 일반 한우농가 개량방향에 효율적인 기초자료로 활용하고자 한다. 일반농가 한우 107,020두 중 생산정보와 2008년부터 2012년까지의 도체성적 기록이 정확한 일반농가 한우 5,843두를 대상으로 다형질 개체모형을 사용하여 유전력를 추정하였다. 유전력를 추정하기 위해 도체형질에는 출생년도, 사육지역을 고정효과, 사육일령을 공변량으로 포함하였다. 일반농가 한우의 유전력를 추정한 결과 도체형질에 대한 유전력은 도체중 0.19, 등심단면적 0.17, 등지방두께 0.20, 근내지방도 0.23 이며 국가단위 씨수소 선발용 후대검정우 집단의 유전력에 비해 낮았다. 이는 사육지역의 환경, 암소 유전능력과 사육개월의 차이로 인해 낮게 나타났다. 따라서 본 연구에서도 현재 실시되어지고 있는 국가단위 씨수소 선발용 개체모형에 농가 한우집단에 사용할 수 있는 유전요인을 포함시켜 실용화 개체모형 개발이 시급하다.

• 척추신경추나의학회지
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• 제2권1호
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• pp.127-152
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• 2007

Objectives : To research the trend of the study related to Chuna(推拿) and to establish the direction of further studies into the Chuna(推拿). Methods : We reviewed and analyzed all theses published by Korean research institution. And these theses were classified by research institutions, published year, field of study, subject, research methods, thesis types, illness and symptoms. Results : The following results were obtained in this study. 1. Classified by the major field of study, oriental medicine accounted for 59 papers, followed by 18 in physical education and 2 in the science of nursing and medicine. 2. Upon classifying theses according to research method and thesis types, research related to clinical trial accounted for nearly half of all theses. It was followed by consideration of documents. 3. After 1998 deals with the effects of the Chuna on variable illnesses such as: ossified posterior longitudinal ligament, chronic coccyalgia, entrapment neuropathy, low birth weight infant, Bell's palsy, stress incontinence, paramenia, Parkinson disease, Bertolloti syndrom, TMJ (because of scoliosis) etc. 4. Two most widely cured illnesses using the Chuna therapy are scoliosis and HNP of L-spine. However, when considering the fact that several clinical tests and casuistics did not include research into Lumbago (including HNP of L-spine), it can be concluded that most of the Chuna therapies have been concentrated on Lumbago. Conclusion : As it can be seen in the above results, the possibility of curing illness through Chuna and the usefulness of Chuna have been shown factually and clinically through various consideration of documents, clinical trial & casuistics. Based upon such facts, it is regarded that further scientific research along with additional clinical approaches involving the Chuna should be performed.

• Journal of Preventive Medicine and Public Health
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• 제48권3호
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• pp.170-177
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• 2015

Objectives: The goal of this study was to examine the association of various demographic and socioeconomic factors with risk factors for chronic kidney disease (CKD). Methods: We used nationally representative pooled data from the Korea National Health and Nutrition Examination Survey (KNHANES), 2007-2013. We estimated the glomerular filtration rate (GFR) using the Modification of Diet in Renal Disease equation. We defined CKD as a GFR <60 mL/min/$1.73m^2$, and 1304 of the 45 208 individuals included in the KNHANES were found to have CKD by this definition. The outcome variable was whether individual subjects adhered to the CKD prevention and management guidelines recommended by the Korea Centers for Disease Control and Prevention. The guidelines suggest that individuals maintain a normal weight, abstain from alcohol consumption and smoking, manage diabetes and hypertension, and engage in regular exercise in order to prevent and manage CKD. Results: This study found that individuals with CKD were more likely to be obese and have hypertension or diabetes than individuals without CKD. In particular, male and less-educated CKD patients were less likely to adhere to the guidelines. Conclusions: Although the prevalence of CKD, as indicated by the KNHANES data, decreased from 2007 to 2013, the prevalence of most risk factors associated with CKD fluctuated over the same time period. Since a variety of demographic and socioeconomic factors are related to the successful implementation of guidelines for preventing and managing CKD, individually tailored prevention activities should be developed.