• 한국정밀공학회지
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• 제24권6호
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• pp.121-130
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• 2007

In this paper, we present the development of a new training system for equilibrium sense and postural control. This system consists of an unstable platform, a force plate, a computer, and training programs. The unstable platform provides 360 degrees of movement allowing for training in all directions. To evaluate the effects of the training system, we performed various experiments to train the ability of equilibrium sense and postural control of fifteen young healthy subjects. We measured the time a subject maintains his or her center of pressure on a target, the time a subject moves his or her center of pressure to a target, and the mean absolute deviation of the trace before and after the training. We analyzed these parameters obtained before and after the training using paried-sample T-test. The result shows that the subjects experienced distinctive enhancement in their ability of postural control through the training using our system.

• The Journal of Asian Finance, Economics and Business
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• 제8권5호
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• pp.769-775
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• 2021

The objective of this research was to analyze the factors influencing the farm-gate shrimp prices in Thailand using monthly time series from January 2001 to December 2019. The econometric methodology was employed to satisfy the purpose, consisting of the cointegration test for revealing the long-run relationship and equilibrium elasticity between the variables as well as the error correction model for detecting speed adjustment to shock responses. The empirical results revealed that (1) the export shrimp prices, shrimp production in the country, and shrimp export volume indicated a long-run relationship running to the farm-gate shrimp prices in Thailand with the size of equilibrium elasticity equal to 1.083%, -0.256%, and 0.123, respectively, and (2) the farm-gate shrimp prices in Thailand would adjust to the equilibrium line with a speed equal to 20.147% if there was any kind of incident or shock which caused the relationship to deviate from the equilibrium point. There was no relationship in terms of global shrimp prices and the exchange rate for farm-gate shrimp prices in Thailand. The recommendations should emphasize the varieties of shrimp products for export to other countries beyond the main trading markets nowadays to reduce risks and fluctuations in the export prices of shrimp products.

• International journal of advanced smart convergence
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• 제11권3호
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• pp.197-205
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• 2022

In order to investigate the effect of an 8-week elastic band exercise program according to age on the isokinetic strength and dynamic equilibrium of the knee, 10 women under 49 years old and 10 women over 50 years old were selected. Dynamic equilibrium was measured through Y-Balance test one week before the exercise program, and power and endurance were confirmed by measuring isokinetic muscle strength of the knee. After measurement, small tool exercise was performed for 8 weeks. After 8 weeks of exercise, isokinetic muscle strength and dynamic equilibrium were measured. As a result, isokinetic muscle strength, which checks muscle strength and muscular endurance, increased after measurement than before measurement regardless of age, and dynamic equilibrium increased after measurement rather than before measurement, and the group under 49 years of age was higher than the group over 50 years old. We think that small tool exercise improves isokinetic muscle strength and is effective in neuromuscular development, improving dynamic stability ability, which is an important factor in preventing falls.

• 한국정밀공학회지
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• 제11권4호
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• pp.58-68
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• 1994

An equilibrium approach is suggested as an effective tool for the analysis of sheet metal forming processes on the basis of force balance together with geometric relations and plasticity theroy. In computing a force balance equation, it is required to define a geometric curve approximating the shape of the sheet metal at any step of deformation from the geometric interaction between the die and the deforming sheet. Then the geometic informations for contacting and non-contacting sections of the sheet metal such as the number and length of both non-contact region, contact angle, and die radius of contact section are known from the geometric forming curve and utilized for optimization by force balance equation. In computation, the sheet material is assumed to be of normal amisotropy and rigid-phastic workhardening. It has been shown that there are good agreements between the equilibrium approach and FEM computation for the benchmark test example and auto-body panels whose sections can be assumed in plane-strain state. The proposed equilibrium approach can thus be used as a robust computational method in estimating the forming defects and forming severity rather quickly in the die design stage.

• 한국과학교육학회지
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• 제18권3호
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• pp.303-312
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• 1998

본 연구는 화학 평형 단원에 대한 멀티미디어 CAl를 제작하고, 고등학교 화학수업에 적용하여 성취도와 태도 면에서 전통적 수업과의 효과를 비교하였다. 이를 위하여 수업처치 전에 화학수업과 컴퓨터에 대한 태도 검사를 하였고, 중간고사 성적을 공변인으로, 중간고사의 과학성적을 구획변인으로 사용하였다. 화학 평형 단원을 대상으로 각각 전통적인 수업과 CAl를 수행한 후에 성취도 검사와 태도 검사를 실시하였다. 컴퓨터를 이용하여 화학수업을 받은 학생은 전통적인 수업을 받은 학생에 비하여 성취도는 유의미하게 향상 되었으나, 태도의 향상은 유의미하지 않았다. 또한 학습자의 사전 성취수준과 수업처치와의 상호작용은 관찰되지 않았다. 성별로 분석해 보니 여학생은 CAl에 의해 성취도가 향상되었으나, 남학생은 차이를 보이지 않았다. 이해와 적용의 하위범주 중 적용문제 영역에서 CAl에 의한 성취도의 향상이 있었으며, 화학 평형의 법칙, 화학 평형의 개념, 평형 이동의 적용 세 부분으로 나누었을 때 화학 평형의 개념에서 성취도의 향상이 가장 컸다. CAl가 컴퓨터에 대한 태도와 화학수업에 대한 태도에 긍정적인 변화를 주지 않았으며, 남학생은 CAl에 의해 화학수업에 대한 태도와 컴퓨터에 대한 태도 모두 긍정적으로 변했으나 여학생은 그렇지 못하였다. 이상의 결과에 대한 교육적 의미를 논의하였다.

• 한국응용과학기술학회지
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• 제38권2호
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• pp.608-617
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• 2021

이 연구의 목적은 8주간의 코어 훈련이 프리스타일 스키 선수들의 배근력, 서전트 점프, Y-자 검사 및 평형감각 조절 능력에 미치는 영향을 보고자 하였다. 14명의 프리스타일 선수를 무작위로 운동군 7명과 통제군 7명으로 분류하였다. 훈련군은 8주간의 코어 훈련을 하였고, 통제군은 일반적인 훈련을 하였다. 연구 결과 배근력과 서전트 점프에서 효과를 보였고, 집단 간 유의한 차이는 보이지 않았다. Y-자 검사의 경우 좌측 앞쪽에서 효과를 보였고, 좌·우측 좌측 후방 안쪽에서 집단 간 차이를 보였다. 종합점수의 경우 운동군은 사전의 좌·우 차이 7.5cm, 사후에서 1.66cm로 감소하였으나 통제군은 사전 3.73cm에서 사후 7.01cm로 증가한 것으로 나타났다. 평형감각 조절 능력에서는 조건 2, 5, 6에서 유의한 효과를 보였으나 집단 간의 차이는 없었다. 결론적으로, 8주간의 코어 훈련은 프리스타일 스키선수들의 자세 조절 능력에서 유익한 효과를 미치는 것으로 나타났다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.109-112
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• 2007

In this paper, a mathematical modeling was developed to simulate 1kW class air cooled Polymer Electrolyte Membrane Fuel Cell(PEMFC) system. The proposed modeling was conducted under SIMULINK based environment. The model ing was developed based on the thermodynamic and chemical equilibrium. The objective is to design and implement the entire fuel cell system model ing including the system controller modeling. The fuel cell process and the control system modeling should have to be connected with each other simultaneously， therefore the two types of modeling influences each other when the system simulator run. The fuel cell modeling libraries are simulated using the SIMULINK under the thermodynamic and chemical equilibrium base. The PID controller application was designed and developed to test the process modeling and verify it. This the prototype development of the fuel cell system to design and test more complicate fuel cell systems, like the residential power generation system. The simulation results was compared to the real PEMFC system performance. We have achieved the reasonable accordance with the Lab test and the simulation results.

• International Journal of Reliability and Applications
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• 제13권1호
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• pp.49-56
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• 2012

Using total time on test transform (TTT), a new approach is taken for testing exponentiality versus the unknown age, exponential better than equilibrium life in convex ordering (EBELC). Selected critical values are tabulated for sample size n =2(2)50 and powers of the test are estimated for some commonly used distributions in reliability. Finally real example is presented to illustrate the theoretical results.

• 사상체질의학회지
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• 제22권4호
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• pp.30-39
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• 2010

1. Objectives This study was carried out to investigate the equilibrium functional difference according to mean velocity of basilar artery with Sasang Constitution. 2. Methods We analyzed the data of 300 adults(194 males, 106 females), who visited oriental hospital of D university for medical examiation, which includes Sasang constitution examination, equilibrium function test, transcranial doppler ultrasonography(TCD). We evaluated the trace length and envelop area of open eyes and closed eyes, mean velocity of basilar artery and analyzed its statistical data. 3. Results and Conclusions 1) Within all subjects, trace length and envelop area of closed eyes were significantly lower, in the order of increased mean velocity of basilar artery group, normal mean velocity of basilar artery group and decreased mean velocity of basilar artery group. 2) No significantly difference was seen between the mean velocity of basilar artery and equilibrium function in Soyangin and Soeumin. 3) When closed eyes, trace length were significantly lower in order of increased mean velocity of basilar artery group, normal mean velocity of basilar artery group and decreased mean velocity of basilar artery group, in Taeeumin.

• 대한교통학회지
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• 제19권1호
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• pp.89-99
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• 2001

기존의 고정수요(Fixed Demand)를 전제로 한 가로망 설계 모형에서는 가로망의 구조나 용량이 개선되더라도 장래 기·종점 통행수요는 변하지 않는다고 가정한다. 이는 단기적인 가로망 설계에서는 성립할 수 있지만, 현실적으로 기·종점 통행수요는 네트워크 서비스수준에 따라 변화하므로 고정수요를 전제한 장기적인 가로망 설계문제에서는 그 타당성을 잃어버린다 그러므로 장래 최적 가로망 설계는 현실적 여건과 교통특성상 기·종점 통행 수요가 모형 내부에서 결정되는 내생변수로 처리하는 가변수요(Variable Demand)를 반영한 가로망 설계 문제로 모형을 구축하는 것이 바람직하다. 이러한 맥락에서 본 논문은 가변수요를 갖는 가로망 설계문제에 대한 이중계층 모형을 구축한 다음, 가로망내의 특성치가 변화하였을 때 그 파급영향을 먼저 파악하고 현 가로망 개선에서 가장 먼저 고려해야 할 링크를 찾아내기 위해 민감도 분석을 수행하였고, 민감도 분석과 연관되어 전체 시스템 효과척도를 최적화할 수 있는 대안적인 알고리즘을 제시하고 적용하여 구축된 모형으로 그 유효성을 검증하였고, 기존 고정수요 가로망 설계기법에 내재된 한계점을 극복하고자 하였다.