• 대한전기학회논문지
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• 제32권6호
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• pp.211-218
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• 1983

In this paper, an attempt is made to match the continuous state trajectory of the digital control system with that of its continuous data model. Matching the state trajectories instead of the output responses assures that the performances of the internal variables of the plant as well as the output variables are preserved in the discretization. The mathematical tool used in this research is an extended maximum principle of the Pontryagin type, which enables one to synthesize a staircase type of optimal control signals, such as the output signal of a zero-order hold asociated with a digital controller. A general mathematical expression of the digital controller which may be used to replace the analog controller of a general system while preserving as mauch as possible the performance characteristics of the original continuous-data control system is derived in this paper.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.32-33
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• 2021

When materials are to be transported vertically at the construction site, if the space is small, there is often a precarious situation in which materials are transported outside the scaffold or through the space secured by removing the safety footrest. In addition, if the safety foothold is removed, the reinstallation may not occur due to carelessness of a worker. To solve the problem of this particular case, we have created a safety foothold that is unnecessary to dismantle and can be opened.

• 산업경영시스템학회지
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• 제41권2호
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• pp.117-132
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• 2018

There always exist nonzero inspection errors whether inspectors are humans or automatic inspection machines. Inspection errors can be categorized by two types, type I error and type II error, and they can be regarded as either a constant or a random variable. Under the assumption that two types of random inspection errors are distributed with the "uniform" distribution on a half-open interval starting from zero, it was proved that inspectors overestimate any given fraction defective with the probability more than 50%, if and only if the given fraction defective is smaller than a critical value, which depends upon only the ratio of a type II error over a type I error. In addition, it was also proved that the probability of overestimation approaches one hundred percent as a given fraction defective approaches zero. If these critical phenomena hold true for any error distribution, then it might have great economic impact on commercial inspection plans due to the unfair overestimation and the recent trend of decreasing fraction defectives in industry. In this paper, we deal with the same overestimation problem, but assume a "symmetrical triangular" distribution expecting better results since our triangular distribution is closer to a normal distribution than the uniform distribution. It turns out that the overestimation phenomenon still holds true even for the triangular error distribution.

• 한국의류산업학회지
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• 제12권3호
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• pp.389-397
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• 2010

This study was carried out to investigate the effect of washing machine type (drum or pulsator) on the behavior of clothing management and consumer satisfaction. The data were collected via questionnaires from 408 consumers and were analyzed through factor analysis, ANOVA, Cronbach's Alpha, utilizing SPSS 10.0. The results of this study were as follows: 1) 39.2% of consumers used drum washer and the number of users has increased sharply in five years. Drum washer consumers hold larger capacity washer than pulsator washer consumers. 2) Young people(under 40) showed statistically significant differences in terms of washing concern and the kinds of detergents, while old people(40 and above) showed statistically significant differences in terms of checking the label, preparing the laundry, and hand-washing. Married women showed statistically significant differences in checking the label, preparing the laundry, and hand-washing. 3) In terms of clothing management behavior with the type of washing machine, drum washer consumers showed statistically significant the amount of detergents, while pulsator washer consumers showed statistically significant handwashing and kinds of detergents. 4) In terms of customer satisfaction with the type of washing machine, drum washer consumers showed statistically significant brand satisfaction.

• 자연과학논문집
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• 제6권1호
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• pp.65-70
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• 1993

우리나라의 최대의 무종자 수입국인 일본은 외국으로부터의 무종자 수입이 채소종자수입의 약 절반을 차지하고 있다. 일본에서 요구하는 무는 우리나라의 고유한 무품종의 형태와 품질과는 차이가 많으므로 무종자의 수출뿐아니라 생식 및 가공품의 수출증대를 위하여 유전자원의 확보, 고품질 재배방법개발 및 품질조사방법의 개선 등을 통한 생태형별, 이용용도별로 세분화된 내병고품질 무 품종육성이 요망된다.

• 지역사회간호학회지
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• 제13권3호
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• pp.481-492
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• 2002

The purpose of this study was to understand and analyze the subjective structure of attitude The method was based on a Q-Methodological approach. The results of this study, there were four categories of smoking middle school students' attitude about smoking. The first type named Self Belief type that this type didn't sensible of their surrounding persons when they were smoking and they also were responsible for strong opinion at their behavior. The second type named Other's Awareness type that they were seen the behaviors they always have to see other person when they were smoked, but if they didn't smoke or have tobaccos they feel heavy and are restless. The third type named Solving of Anxiety type. They first used to smoke when they wanted to solve their anxiety, stress, awkwardness and angry. The fourth type named A Sense of Belonging Group type. This type followed if their friends were smoking they also did it with them. As to grasping of their motivation to smoking of middle school of students with smoking, they felt some intimacy and same quality each other. In consideration of various types of attitude about smoking, it was very necessary important to grasp the meaning because we were known about attitude, belief etc. And then Through getting hold of the meaning, we could understand with their thought and value of Students in middle school. Besides, as a substitute for the students were depending on smoking purposelessly will fix right self-confidence.

• 한국축산시설환경학회지
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• 제15권3호
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• pp.251-262
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• 2009

본 연구는 우리나라 젖소농가의 사육규모별 축사시설 현황을 파악하고자 전국 9개도시의 젖소 50두 이상사육농가 4,198호를 대상으로 축사시설 실태를 조사하였으며 그 결과는 다음과 같다. 50두 이상 전업농가에서 344,514마리를 사육하였으며 농가당 50~99마리 사육규모가 78.9%로 대부분이었고 농가당 평균 사육두수는 82.1두 이었다. 젖소 우사의 건축 시기는 평균 건축연도가 1995년 9월로타 축종에 비하여 노후한 편이었으며 농가당 축사면적은 $1,740.0\;m^2$이었다. 젖소 우사의 건축형태는 톱밥우사 84.0%로 가장 높은 비율을 차지하였고 후리스톨 5.1%, 계류식+톱밥 운동장 17.3%, 기타 4.4%이었다. 규모별 우사의 건축형태는 소규모 농가에서 톱밥우사가 많은 반면, 대규모 농가에서는 후리스톨이 10.9%로서 소규모 농가의 후리스톨 보다 높게 나타났다. 착유시설은 파이프라인 41.5%, 헤링본 22.8%, 탠덤 35.8% 이었으나 50~99두의 소규모 농가는 파이프라인이 48.0%로 많은 반면, 200두 이상에서는 헤링본 38.3%, 탠던 48.9%로 착유실 착유가 많은 것을 알 수 있다. 우사 바닥은 깔짚이 94.9%로 스크레이퍼에 비하여 상당히 높게 나타났으나 대규모 농가에서는 스크레파가 13.1%로 소규모 농가의 6.4%에 비하여 높은 경향이었다. 유우사 지붕의 재질은 슬레이트 32.5%, 비닐 16.3%, 썬라이트 11.1%, 판넬 10.9, 함석 8.8, 강판 8.3%로 조사되었다. 1995년 이전에는 슬레이트가 많았으나 1995년 이후 비닐지붕이 증가하고 있으며 대규모 농가에서도 비닐지붕이 23.8%로 소규모 농가에 비하여 많았다. 우사 외벽 재질은 개방식이 83.3%이며 윈치커튼이 26.8%로 대부분 개병형 우사 이었다. 젖소 사육시설의 사용년수는 착유기 9.2년, 사료자동급이기 7.9년, 급수기 9.2년, 전기시설 10.4년으로 최근 사료자동급이기의 시설개선이 많이 있었던 것으로 나타났다.

• 대한치과보철학회지
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• 제40권4호
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• pp.374-385
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• 2002

A total of 605 implant fixture prosthesis delivered by 3 clinics and 2 laboratories were examined in this study, The object of this study was to determine the proper length of screw head. The depth of access hole were measured and compared to the type of fixture, abutment, gold screw and prosthesis. The results were as follows : 1 The average number of fixtures per patient were 2.97. 2. The number of fixture installed in the upper posterior area are 327(55.56 %), the upper posterior area 171 (28.25%). 3. The depth of access hole is 4.23 mm in shallow area, and 5.46 mm in deep area and the differences were 1.23 mm. 4. The average depth of the aceess hole of the UCLA abutment were 5.02 mm. 5. The number of 4-5 mm access hole depth were 60(22.39%) in abutment screw level and the number of 4-5 mm depth in fixture level were 101 (29.19%). 6. In the shape of screw head, hexed type were 576(95.21%), slotted type were 29(4.79%).

• 대한수학회보
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• 제44권4호
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• pp.651-661
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• 2007

Graph algebras establish a connection between directed graphs without multiple edges and special universal algebras of type (2,0). We say that a graph G satisfies an identity $s{\approx}t$ if the corresponding graph algebra $\underline{A(G)}$ satisfies $s{\approx}t$. A graph G=(V,E) is called an $(xy)x{\approx}x(yy)$ graph if the graph algebra $\underline{A(G)}$ satisfies the equation $(xy)x{\approx}x(yy)$. An identity $s{\approx}t$ of terms s and t of any type ${\tau}$ is called a hyperidentity of an algebra $\underline{A}$ if whenever the operation symbols occurring in s and t are replaced by any term operations of $\underline{A}$ of the appropriate arity, the resulting identities hold in $\underline{A}$. In this paper we characterize $(xy)x{\approx}x(yy)$ graph algebras, identities and hyperidentities in $(xy)x{\approx}x(yy)$ graph algebras.

• 대한조선학회논문집
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• 제53권2호
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• pp.162-169
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• 2016

A new concept of membrane type LNG CCS was proposed. Also, its static behavior was numerically analyzed considering the interaction between primary and secondary barrier together with securing device. Hull deflection was taken into account as an external load, together with temperature distribution across the barriers. The suggested numerical model considers both sliding and contact between the two mating surfaces of both the primary and secondary barrier, and anisotropic material behavior of plywood, R-PUF was also taken into account. Furthermore, detailed local strength was evaluated for the securing device, which is arranged between two barriers to hold the primary barrier. It was confirmed through the numerical analysis that the new concept of membrane type CCS was structurally safe under static loading condition and securing concept was structurally reliable.