• Safety and Health at Work
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• 제10권4호
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• pp.527-530
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• 2019

The increasing prevalence of inactivity and obesity, along with aging, has implications on work capacity of labor force. This study reports the relationships between activity level and BMI by age with objectively measured physical workload. Data were examined from a sample of 19 481 Finnish employees using an estimate of minute-to-minute oxygen consumption based on R-R interval recordings. The mean estimated %VO₂max during the working day was 12.1 (±3.6) and 15.1 (±4.5)% for men and women, respectively. Based on a linear model, the mean %VO₂max increased by 1.5%-unit per 10-year increase in age, by 2.1%-unit per 5 kg/㎡ increase in BMI, and decreased by 1.6%-unit if improving physical activity class by two (p < 0.001 for all). Overweight and obesity, together with inactivity, notably increases workload throughout the career, even though at young adulthood, the daily workload is almost the same for each person regardless of the BMI, activity level, or gender. This study highlights the importance of regular physical activity and normal weight in protecting the worker from excessive physical (cardiovascular) workload during the whole working career.

• 한국해양학회지:바다
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• 제2권2호
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• pp.138-150
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• 1997

한반도 서남 해역에 위치한 함평만(전라남도 함평군) 조간대 퇴적층의 제 4기 후기 층서와 퇴적학적 연구를 위하여 총 37 지점에서 평균 3 m 깊이(최대 5.2 m)의 시추가 실시되었다. 채취된 퇴적물 시료의 입자 조직(grain texture), 퇴적 구조(sedimentary structure), 색(color) 및 광물 조성(mineral composition) 등을 토대로 10개의 퇴적상(sedimentary facies)이 분류되었다. 분석 결과에 의하면, 함평만 조간대 퇴적분지의 층서는 상위로부터 순차적으로 층서단위 Unit I, Unit II 및 Unit III로 구성된다. 최상위의 층서단위 Unit I은 조립질 퇴적상인 비조직 사질역 퇴적상(Facies SGd)과 괴상 역질 이토 퇴적상(Facies GMm) 또는 세립질 퇴적상인 엽층리 실트 퇴적상(Facies Zp), 괴상 이토 퇴적상(Facies Mm) 및 평행 엽층리 이토 퇴적상(Facies Mp)으로 구성되며, 상향 조립화의 특정을 나타낸다. 이 퇴적층은 해수면이 거의 현재의 위치에 도달된 지난 약 4.000년 동안 형성된 후기 현세(late Holocene) 해침 퇴적층으로 해석된다. Unit I에 의하여 부정합적으로 피복되는 층서단위 Unit II는 준 고화된 황색 이토 퇴적상 (Facies Mym)과 회색의 미고결된 니질 퇴적상(Facies Mgm)으로 구성되며, 수평적 연속성이 양호하고, 함평만 전체에 광역적으로 분포한다. Unit II는 서해의 여러 조간대에서 보고된 간월도층과 대비되는 것으로 여겨지며, 후기 플라이스토세(late Pleistocene)의 조간대 퇴적환경에서 집적된 퇴적층으로 해석된다. 이러한 Unit II에는 지난 최대 빙하기 동안 대기중에 노출된 다양한 증거(황갈색, 고화상태, 동토구조, 점토광물의 함량 변화등) 들을 함유한다. Unit II에 의하여 부정합적으로 피복되는 Unit III는 역질의 층리를 갖는 조립의 퇴적물(Facies SGb와 Facies Sx)로 구성되며 내만역의 한정된 지역(후동과 시목동 해역)에 분포한다. 퇴적학적 특성과 지역적인 분포 양상을 고려할 때, Unit III는 육성 환경(nonmarine deposits)의 하천 퇴적물(fluvial sediment)로 해석된다. 결과적으로 함평만 조간대 퇴적분지의 층서(최고기로부터 최신기)는 기반암 지층(중생대 화강암)${\rightarrow}$육성 퇴적층(Unit III)${\rightarrow}$후기 플라이스토세의 니질 조간대 퇴적층(Unit II)${\rightarrow}$후기 현세의 조간대 퇴적층(Unit I)의 층서이며, 각각의 층서단위의 경계는 부정합적이다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.135-138
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• 1999

The objective of this study is to investigate the compressive strength property of antiwashout underwater concrete with curing water through experimental researches. Type of casting and curing water(fresh water, sea water) are used as main experimental parameter, additionally a few variables affecting compressive strength property are used ; water-cement ratio (45%, 48%, 50%, 52%, 55%), and unit weight of admixtures (antiwashout underwater agent ; 0.6%, 0.8%, 1.0%, 1.2%, 1.4% of unit weight of water, superplasticizer ; 0.5%, 1.0%, 1.5%, 2.0%, 2.5% of unit weight of cement)) Compressive strength level of antiwashout underwater concrete which was cast and cured in fresh water is higher than other one. Consequently, incremental modulus has to increase when the antiwashout underwater concrete is made use of underwater work from ocean.

• ETRI Journal
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• 제8권2호
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• pp.109-116
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• 1986

본고는 TDX-1 전전가 교환기의 운용 관리기능인 과금, 통계, MMC 및 데이터 처리기능과 이들을 보조하는 각종 입출력 장치인 TTY(CRT) terminal, disk unit, CT unit, MT unit 및 data link 제어기능에 대하여 기술하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.679-682
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• 2006

By adjusting driving voltage, the image quality and optical characteristics have been improved. Based on the experiment results. Optical properties including viewing angle and color shifts at bias voltage 2.4 V are better than those of bias voltage 1 V.

• Journal of the Korean Statistical Society
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• 제24권2호
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• pp.481-493
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• 1995

An ARIMA signal observed with measurement error is shown to have another ARIMA representation with nonlinear restrictions on parameters. For this model, the restricted Newton-Raphson estimator(RNRE) of the unit root is shown to have the same limiting distribution as the ordinary least squares estimator of the unit root in an AR(1) model tabulated by Dickey and Fuller (1979). The RNRE of parameters of the ARIMA(p,1,k) process and unit root tests base on the RNRE are developed.

• 산업경영시스템학회지
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• 제2권2호
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• pp.39-51
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• 1979

In introducing and applying the budget management system, the question of how to establish management structure(skelton) representing budget management responsible unit is significantly related to the degree of accuracy and analysis on the performance measurement of standard work unit. We have the following rational process of establishing performance measurement of budget management System ; 1) Standardization of work method 2) Establishment of management structure 3) Institution of budget management system. Especially, this system is based on a premise of efficiency of objectives management, it is assumed that performance measurement in the standard work unit must be enforced according to the basis and categories of performance evaluation based on the evaluating work unit. Therefore, most of all, the following three detail questions(subjects) are to be determined in order to rationalize these above principles to a maximum possible extent of performance measurement system. First, we established respective performance standard unit with respect to such detailed work unit, performance standard unit of which were accurately applicable directly from using the budget ana objectives account data and their supplementary data of the work measurement techniques. Second, by using the above mentioned question, over all evaluation and suggestion are made based on the study of the recording for each work unit development, budget management and production nit (volume of production) Third, the measurement of performance of budget management system is based on the principle of standard work unit, compared with the standard basis and actual work unit by period and activities unit and calculated percentage effectiveness according to the above procedure. and so evaluated the efficiency of performance measurement on the budget management system.

• 한국실내디자인학회논문집
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• 제15권3호
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• pp.102-110
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• 2006

The purpose of this study was to find out the spacial characteristics from the $69.42-11.70m^2$ unit plans of the apartment houses in Jeon-ju city, and to check up on the general spacial principles of Korean apartment unit plans. The content analysis method and the survey method were used for this study. The data of apartment unit plans and the questionnaires were collected from apartment offices or real estate agency offices. The data of 157 unit plans and 190 questionnaires were analyzed. The results of this study were as follows; 1) The general spacial principles of Korean apartment unit plans, the tendency of front 3-bay unit plan, the openness of living room, the Anbang with a bathroom and a dressroom, the utility room as a kitchen support space, and the addition of balconies, were showed in those of Jeon-ju city. 2) There was a new tendency, the front room arrangement of Anbang-living room-bedroom was changed into Anbang-living room-bathroom or kitchen, in them. 3) The characteristics of L-DK floor plans that the closeness of DK from exterior space and the interior openness and exterior privacy of L were showed in them. 4) The entrance was needed a intermediate space as a balcony or a former space, in them. These tendencies on unit plans of the apartment houses in Jeon-ju city were followed the general spacial principles of Korean apartment unit plans.

• Nuclear Engineering and Technology
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• 제26권1호
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• pp.9-18
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• 1994

월성 원자력발전소의 안전계통은 비상사태시에만 작동하는 3분의 2논리로 구성되어 있다. 그들의 작동성을 보증하기 위해 이 안전계통은 주기적으로 점검되어진다. 본연구에서 사람의 실수가 고려되어진 3분의 2논리 구성 시스템에서의 불이용도가 계산되어졌다. 그리고 우리는 시험기간중에 사람의 실수또는 기계의 고장으로 인해 발전정지를 일으킬 확률을 구했다. 우리는 이 불이용도와 발전정지를 일으킬 확률을 둘다 고려하여 적정한 최적점검주기를 계산하였다. 이렇게 얻어진 점검주기와 현재 사용되는 점검주기를 비교하면 사람의 실수를 최소(8.24 $\times$ $10^{-6}$ )로 보았을때 최적점검주기는 현재 사용되는 점검주기 보다 조금 짧았고 사람의 실수를 최대 (4.44 $\times$ $10^{-4}$ )로 보았을 때 최적점검주기는 현재 사용하는 점검 주기보다 다소 긴 것으로 계산되어졌다.

• 한국기계가공학회지
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• 제7권2호
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• pp.45-51
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• 2008

The objective of this study is to develop an automatic object changer unit to improve processing problems existed in the conventional horizontal machining center. In order to perform this objective, a upward and downward traverse unit in which a unit that consists of a motor and reducer, chain and sprocket wheel, and upper and lower base employed in an automatic object changer unit performs sliding contact motion in a frame was designed. To achieve this design, constraint conditions for the upward and downward traverse unit first designed. Then, an operation mechanism was designed and that was introduced as a sum of kinetic energy for the sprocket wheel and upper and lower base based on the moment of inertia, which is the kinetic energy of the converted upward and downward traverse unit in the side of the reducer. In addition, The work required to rotate the converted upward and downward traverse unit in the side of the reducer by one revolution can be calculated using the sum of work that is required in the sprocket wheel and upper and lower base that is a part of the upward and downward traverse unit. Furthermore, the converted equation of motion in the side of the motor can be introduced using the equation of motion using the converted upward and downward traverse unit in the side of the motor. Then, Then, a proper motor can be determined using predetermined specifications employed in the motor and several parameters in the upward and downward traverse unit in order to verify such predetermined specifications. Also, a design of a horizontal traverse unit that performs sliding motion on a upward and downward traverse unit and simulation that verifies the results of this design are required as a future study.