심혈관질환 위험 요인과 맥파속도의 관계

이태용,안병희,김광환,김용하,한상태 한국자료분석학회 2009 Journal of the Korean Data Analysis Society Vol.11 No.1

The objective of this study is to investigate the association between various cardiovascular risk factors(hypertension, high LDL-cholesterol, low HDL-cholesterol, diabetes, smoking, age, obesity, psychological factor etc.) and brachial-ankle pulse wave velocity (baPWV). 995 subjects aged between 40 and 70 living in 1 county Chungchengnam-Do Korea were selected and evaluated on disease, family, occupation, smoking and drinking history, payment for medical treatment, extent of physical activity, psychosocial history. This research showed that various cardiovascular risk factors such as age, systolic blood pressure, diastolic pressure, intestinal fat(kg, %), disease history, economic status, activities of daily living are significantly correlated with baPWV. Therefore, physicians must consider baPWV along with other various risk factors for diagnosis, treatment, and prevention of cardiovascular disease. 본 연구에서는 2006년 1월부터 2월까지 1개군에 거주하는 40세 이상부터 70세까지의 성인 995명을 대상으로 심혈관계 및 대사 질환의 대표적인 위험 요인들과, 개인에서 질병 발생과 연관된 인구 사회학적 요인, 사회심리학적 요인 등이 상완-발목 맥파속도에 미치는 영향과 맥파속도의 임상적 유용성을 평가해 보고자 한다. 신체검사와 설문조사를 실시한 결과 수축기 혈압이 가장 중요한 변수로 선택되었고, 다음으로 연령, 체질량 지수, 뇌졸중 여부, γGTP 등의 순으로 나타났으며, 이런 변수들에 의한 설명력은 50.6%이었다. 본 연구를 통해 우리나라의 일반 인구집단 내에서 심혈관계질환의 위험 요인들인 나이, 수축기 및 이완기 혈압 외에 내장 지방량, 내장 지방률, 질병력, 사회심리적 요인, 경제적 요인, 일상생활 동작 등 여러 요인들이 동맥경화도를 나타내는 맥파속도와 유의한 관계가 있다는 것을 알게 되었다. 따라서 추후 일반인을 대상으로 심혈관계질환의 진단과 치료, 예방 시 맥파속도를 고려해야 할 것으로 생각한다.

Scheduling of Embedded System Using a Petri Net

이태용 한국정보과학회 프로그래밍언어연구회 2004 프로그래밍언어논문지 Vol.18 No.3

Embedded systems specification usually has both data computation and control structures. Control structure can be two types. One is data dependent control and the other is real time control. The first one can be easily solved because it is involved with only one task and its behavior is very obvious. The problem is the second case. We must use some sophisticated techniques to resolve concurrent behavior of tasks. To solve the second problem, these tasks require to be scheduled on a shared resource such as processor and memory. This scheduling is mainly based on the system specification. To simulate dynamic behaviors of system, it is very difficult to predict these behaviors because these behaviors have to be determined at compile time and decisions have to be made at run time. In other words, scheduling must be efficiently made while pleasing real time constraints and using the processor and memory resources as efficiently as possible. Therefore, Quasi-static scheduling algorithm is used to solve these problems.

A Simulation of Age-related Expansion of the Femoral Neck Cortex on the Susceptibility to Local Buckling

이태용,Benjamin W. Schafer,Thomas J. Beck 대한골다공증학회 2007 Osteoporosis and Sarcopenia Vol.5 No.2

Aging bones preserve bending resistance by compensating bone loss with periosteal apposition, but the process does not prevent fragility fractures. One explanation is that thinning with expansion in the cross-sectional cortex increases local buckling susceptibility under abnormal loads. In this study, theoretical models of femoral neck cortices were developed from CT scans of 7 human femurs(4 female, 3 male, 52~68 years). To simulate aging, “younger” and “older” versions were created by radially contracting(young) and expanding(old) outer surfaces by 1mm. Inner cortices were then adjusted so that load stresses in a single-legged stance equilibrated. Additional “old” versions simulated adaptation to 10% and 20% reduced loads as might occur in frail elderly. Adaptation consequences were evaluated in a simulated fall on the greater trochanter. Finite Strip Method(FSM) was used to evaluate whether buckling reduced the failure load. Under constant loading, buckling reduced the failure load in two “middle aged”(9~15%) and five “old”(7~32%) models. Up to 51% of failure load reduction was observed after adaptation to reduced loads. Femoral neck expansion with thinning cortices preserves strength under physiologic loads but local buckling reduces failure load in falls, especially after elderly cross- sections are thinned by adaptation to reduced loads. 목적: 우리 신체의 항상성은 노화가 진행되면서 골절에 대한 저항력을 골막의 증가와 그에 따른 골량의 감소로 보상하는 체계를 유지한다. 하지만 노령화에 적응하는 항상성 자체가 공학적인 측면에서는 국소적 휨(local buckling)에 따른 골절을 유발할 수도 있다. 이는 노령 인구의 골절이 단순한 골밀도의 감소뿐만 아니라 골의 구조적인 변화 자체에 기인할 수도 있음을 뜻한다. 방법: 이 연재에서는 대퇴골의 CT 단층 촬영을 이용해 고관절 피질골의 노령화에 따른 불안정성(Instability)이 어떻게 골절을 유발하는지 고찰해 보고자 한다. 일곱 환자(52~68세)의 CT에서 NHANES(National Health And Nutrition Examination Survey) III에 기인해 각 환자의 20대 및 80대의 대퇴골 단면을 유출했다. 좀 더 현실적인 모델링을 위해서 80대 대퇴골 단면은 항상성에 기인한 하중이 10%와 20% 줄어든 경우까지 고려해서, FSM(Finite Strip Method)을 이용해 대퇴골경에 충격이 가해지는 경우로 분석했다. 결과: 국소적인 휨은 두 50대 환자와 다섯 80대 환자에서 각각 9~15%와 7~32%의 골절하중을 줄이는 것으로 나타났다. 또한 항상성에 기인한 하중이 줄어든 모델에서는 51%까지의 골절하중이 줄어드는 것으로 목격되었다. 이는 대퇴골의 피질 형상에 기인한 불안정성(Instability)이 골절에 상당한 영향을 미친다는 가정을 뒷받침한다. 결론: 본 연구는 노화에 따른 골절의 증가가 골소실뿐만 아니라 항상성에 기인한 불안정성에 있음을 보여준다.

제조업의 혁신 추진을 위한 정책방향

이태용 대한산업공학회 2005 ie 매거진 Vol.12 No.3

CBCT를 이용한 한국인 고령환자의 상악 대구치에서 치근 및 근관형태의 분석

이태용,김미연,김선호,김정희,Lee, Tae-Yong,Kim, Mi-Yeon,Kim, Sun-Ho,Kim, Jeong-Hee 대한치과보철학회 2020 대한치과보철학회지 Vol.58 No.2

Purpose:The aim of the present study was to evaluate the incidence of the second mesiobuccal (MB2) canal, root fusion, and C-shaped root canal configuration in the Korean maxillary first (MM1) and second (MM2) molars by analyzing cone-beam computed tomographic (CBCT) images. Materials and methods: Patients undergoing presurgical CBCT examination were included in the current study. The CBCT images of 1498 MM1 and 1742 MM2 from 1658 Korean patients were assessed to determine the incidence of a MB2 canal, the types of canal configurations, root fusion, and C-shaped root canal configurations. Further, the correlations between the incidence of MB2 canal and age, gender, and tooth position were analyzed. Results: The study population was relatively old (mean age: 66.1 years). The percentage of MB2 canals in MB roots was 60.1% and 28.0% in MM1 and MM2, respectively, with the most common configurations being Weine type III in MM1 and Weine type II in MM2. Additionally, the frequency of a MB2 canal decreased with age in both molars and was higher in men than in women in the MM1 only. Furthermore, root fusion was present in 2.3% and 26.2% of the MM1 and MM2, respectively, whereas C-shaped root canals were observed in 0.4% and 2.7% of the MM1 and MM2, respectively. Conclusion: The MB2 canal was found more frequently in the MM1, whereas root fusion and C-shaped root canals were both seen more frequently in the MM2.

전력부하관리의 필요성 및 효과

이태용 대한전기협회 1985 대한전기협회지 Vol.- No.105

들기/내리기 빈도와 회복시간 변화에 따른 몸통 근육의 피로도 분석

이태용,김정룡,신현주,Lee, Tae-Yong,Kim, Jeong-Ryong,Sin, Hyeon-Ju 대한인간공학회 2006 대한인간공학회지 Vol.25 No.2

The purpose of this study was to investigate the relationship between the cumulative fatigue of trunk muscles and the period of recovery time during repetitive lifting and lowering task with two different frequencies(4 times/min and 6 times/ min). Eight healthy males with no prior history of LBD(low back disorders) volunteered for this study. Subjects had 2, 3, 4, and 5 minutes recovery time respectively while they were preforming the lifting and lowering task at 15% level of MVC. EMG signals from six trunk muscles were collected and the fatigue level was analyzed quantitatively. In results, the fatigue levels of LES(left elector spinae), RLD(right lattissimus dorsi), LLD(left lattissimus dorsi), RRA(right rectus abdominis) and LRA(left rectus abdominis) were recovered when 3 minutes recovery time was given at 4 times/min frequency. However, the fatgue level of RES(right elector spinae) was recovered when 4 minutes recovery was given. On the other hand, when 6 times/min frequency was used, the RLD, LLD, RRA and LRA were recovered at 5 minutes of recovery time. But for RES and LES, it took longer than 5 minutes to be recovered. This results can be applied to design the adequate length of recovery time to control the cumulative fatigue of trunk muscles in industry with repetitive lifting and lowering task.

마을보건 요원의 활동력 평가

이태용,Lee, Tae-Yong 대한예방의학회 1984 Journal of Preventive Medicine and Public Health Vol.17 No.1

In order to develop some indicies for the evaluation of village health worker's activities and to find out personal characteristics and other factors that affect the activities, an interview survey was conducted to thirty seven village health workers (VHW) in Sunwon, Naega and Bulun townships in Kangwha county, where the Community Health Project of Yonsei University, College of Medicine, has been implemented for the past ten years. In addition, daily activity records of the VHW's were also analyzed. The results are summarized below: First, meeting attendance rates, number of regular family visits, number of antenatal care visits and number of family planning visits were identified as the most meaningful criterion for the evaluation of the village health worker's activities. Second, personal factors that significantly affect the village health worker's activities were identified as age, educational background, living with in-laws, religion, presence of preschool child in the family, holding leader's position of village woman's association concurrently, and duration serving as a VHW. The more aged and the more educated VHWs were the more effective. Those VHWs who were living with in-laws, without preschool child in the family, holding the leader's position of the village woman's association, and the longer service duration were the more effective. Other factors that affect the VHW's activities were the number of households in the target village and the number of natural villages in the target villages. It showed that the smaller the size of number of households and natural villages, the higher the degrees of the effectiveness of the VHW.

우리나라 성인에서 혈청 콜레스테롤 수준과 우울증의 연관성에 대한 융복합적 연구

이태용,최세묵 한국디지털정책학회 2015 디지털융복합연구 Vol.13 No.5

Improvement of Viscoelastic Damping in Nickel Aluminum Bronze by Indium-Tin

이태용 대한금속·재료학회 2011 METALS AND MATERIALS International Vol.17 No.3

Reduction of the vibration noise from submarine propellers is of interest in naval operations. Such an objective can be achieved via the use of materials with the ability to dissipate energy of vibration by means of heat, i.e. high damping materials. An additional problem is that the extreme hydrostatic pressure environment of a submarine requires the chosen material to exhibit considerably high stiffness. Most materials demonstrate a compromise between the two properties, i.e. stiffness and damping. This paper aims to discuss research into high stiffness and high damping materials conducted using a dynamic mechanical analyzer (DMA) under variations of testing temperature, frequency, and strain amplitude. Alloys of nickel aluminum bronze and indium tin are the subjects of this study. Defect damping represents a large portion of the overall damping properties of the nickel aluminum bronze while increasing indium content is shown to boost the damping properties of the indium tin alloy. The study then continues with the development of a new material that combines both indium alloying and defects introduction into the nickel aluminum bronze alloy. The new alloy is observed to have high damping, as measured in its high tan δ, with minimum reduction of the stiffness |E*|.