• 대한수학회지
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• 제56권6호
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• pp.1561-1597
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• 2019

In this paper we introduce the notions of topological entropy and topological pressure for non-autonomous iterated function systems (or NAIFSs for short) on countably infinite alphabets. NAIFSs differ from the usual (autonomous) iterated function systems, they are given [32] by a sequence of collections of continuous maps on a compact topological space, where maps are allowed to vary between iterations. Several basic properties of topological pressure and topological entropy of NAIFSs are provided. Especially, we generalize the classical Bowen's result to NAIFSs ensures that the topological entropy is concentrated on the set of nonwandering points. Then, we define the notion of specification property, under which, the NAIFSs have positive topological entropy and all points are entropy points. In particular, each NAIFS with the specification property is topologically chaotic. Additionally, the ${\ast}$-expansive property for NAIFSs is introduced. We will prove that the topological pressure of any continuous potential can be computed as a limit at a definite size scale whenever the NAIFS satisfies the ${\ast}$-expansive property. Finally, we study the NAIFSs induced by expanding maps. We prove that these NAIFSs having the specification and ${\ast}$-expansive properties.

• 한국조경학회지
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• 제41권1호
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• pp.60-70
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• 2013

본 연구는 조경공사 표준시방서 식재공사의 분류체계, 기술방식, 품질기준의 개정시기별 변화특성을 분석하고, 국외 사례와의 비교를 통하여 개선방향을 제시하고자 하였다. 이에 본 연구의 결과 및 제언은 다음과 같다. 1. 개정을 통해 다양한 세부공종이 신설 수정되었으나 상 하위분류가 맞지 않아 시방내용이 상충되고 있으므로 비슷한 공사끼리의 재분류가 필요하다. 2. 시방서 내용을 용이하게 전달하기 위한 기술방식으로 수정이 이루어졌다. 그러나 구체성이 떨어지는 애매모호한 표현과 용어로 유지되고 있는 굴취시 뿌리분의 깊이, 지주재 강도에 관한 내용은 수정이 필요하다. 또한 표토의 채취시기, 약제 살포시기 등은 계량화될 필요가 있으며, 시방규정의 공정성을 고려하여 감독자의 지시에 따르도록 작성된 기준은 수정되어야 한다. 3. 시대적 패러다임과 사용자의 요구를 반영한 품질기준이 제 개정되었으나 구체적이지 않아 수정이 필요하며, 관련 기준들의 국외 사례를 참고하여 수목재료의 품질수준, 식재적기, 굴취시 뿌리분의 크기, 성능기준 등을 개선해야 한다. 개정을 통해 식재공사의 세부공종별 재료 및 시공방법에 대한 내용은 갖춰졌다. 그러나 구체성이 떨어지고 명확하지 않은 기준들로 시방서의 현장 활용을 저해하고 있다. 이에 표준시방서의 분류체계, 기술방식, 품질기준의 문제점 도출과 개선방향의 제시가 필요하며, 이는 향후 표준시방서 개정시 참고자료가 될 수 있다.

• 한국의상디자인학회지
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• 제25권3호
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• pp.17-29
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• 2023

This study collected and analyzed reference information on the size labeling method and size of clothing products in 13 online shopping malls for plus size women in their 20s and 30s, and compared the size specification information focusing on jeans. First, in the results of examining the method of clothing size designation, clothing sizes indicated by 1, 2, 3 or physique designation (M, L, XL) differed between shopping malls, and even in the same shopping mall, even if the same size notation was used. Most the clothing sizes were different depending on the type of clothing. For bottoms, it was found that one company used seven size designation methods at the same time, two shopping malls used four size designation methods, and five shopping malls used three size designation methods. In the meantime, in the results of comparing the size specifications of jeans XL (size 88, 32 inches) by product part, for waist and hip circumferences, each of the eight companies showed that the size was smaller than the body size suggested by KS adult women's wear.

• 한국산학기술학회논문지
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• 제16권9호
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• pp.6397-6402
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• 2015

본 연구는 lab-scale로 제작된 가압식 마이크로버블 발생장치의 버블크기 분포를 분석하여 장치의 최적 운전조건을 검토하고 벤튜리 노즐 제원에 따른 마이크로버블 발생 특성을 확인하였다. 실험결과, 실험실 규모의 가압식 마이크로버블 발생장치의 운전조건은 공기 주입율 0.3 LPM, 가압탱크압력 3 bar, 벤튜리 노즐을 수조와 직접 연결 하였을 때, 상대적으로 우수한 성능을 나타내었다. 벤튜리 노즐 제원을 달리한 마이크로버블 발생 특성에서는 노즐의 제원에 따른 버블크기 분포에 미치는 영향은 낮지만, 버블 발생의 성능적 측면에서는 노즐의 목 직경이 3-4 mm 일 때, $D_{50}$이 $54.98-61.19{\mu}m$(D3L15, D4L15), $50{\mu}m$이하의 버블 분율은 각각 0.326, 0.345(D3L15, D4L15)로 상대적으로 우수함을 확인하였으며, 노즐 목 길이의 경우 목 길이가 20 mm인 노즐의 $D_{50}$이 $49.40-54.98{\mu}m$, $50{\mu}m$이하의 버블 분율은 0.447로서, 마이크로버블을 비교적 안정적으로 발생시키는 것을 확인 할 수 있었다.

• 정보처리학회논문지D
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• 제17D권6호
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• pp.431-442
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• 2010

임베디드 시스템은 하드웨어와 소프트웨어 요소들이 서로 결합된 시스템이기 때문에 설계 시 실시간성(Real-time), 반응성(Reactive), 소규모(Small Size), 경량화(Low Weight), 안전성(Safe), 신뢰성(Reliable), 견고성(Harsh Environment), 저비용(Low Cost) 등의 요소들을 고려하여 설계해야 한다. 그러나 현재 임베디드 시스템 개발에 이러한 요소들을 반영한 설계 기법들이 미비하게 제시되어 있다. 특히 임베디드 시스템 개발에 있어서 프레임워크를 기반으로 임베디드 시스템을 개발하는 형태가 거의 이뤄지고 있지 않다. 이로 인해 현재 개발되어 있는 임베디드 시스템들의 내부 코드들을 살펴보면 시스템 작동과 전혀 상관이 없는 코드들이 무수하게 잔재하고 있으며, 임베디드 시스템 개발에 있어서 재사용성이나 가변성에 대한 고려가 미흡한 실정이다. 따라서 본 연구에서는 임베디드 시스템의 재사용성을 향상시키기 위해 제안했던 재사용 프레임워크 설계에 대한 완전성이나 일관성을 보장하기 위해 Z를 이용하여 프레임워크 설계에 대한 정형 명세 기법을 제시하고자 한다. 또한 Z 언어를 통해 명세한 결과를 Z-Eves Tool을 통해 Z 모델 체킹을 수행하여 프레임워크 설계의 명확성을 보이고자 한다.

• 대한안전경영과학회지
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• 제15권1호
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• pp.283-292
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• 2013

This paper aims to propose a new steps of hypothesis testing using analysis process and improvement process in the six sigma DMAIC. The six sigma implementation models proposed in this paper consist of six steps. The first step is to establish a research hypothesis by specification directionality and FBP(Falsibility By Popper). The second step is to translate the research hypothesis such as RHAT(Research Hypothesis Absent Type) and RHPT(Research Hypothesis Present Type) into statistical hypothesis such as $H_0$(Null Hypothesis) and $H_1$(Alternative Hypothesis). The third step is to implement statistical hypothesis testing by PBC(Proof By Contradiction) and proper sample size. The fourth step is to interpret the result of statistical hypothesis test. The fifth step is to establish the best conditions of product and process conditions by experimental optimization and interval estimation. The sixth step is to draw a conclusion by considering practical significance and statistical significance. Important for both quality practitioners and academicians, case analysis on six sigma projects with implementation guidelines are provided.

• 패션비즈니스
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• 제5권3호
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• pp.9-18
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• 2001

This study is to provide basic data for the development of domestic ready-made shoes industry by illustrating any problem in regards to the ready-made shoes for ordinary salary men through looking into its uses and gratifications. Subjects for this study were in between twenties and sixties by applying convenient random sampling method, which was done in January to February, 2001. The results were as follows: 1. General foot shape of subjects was that foot breadth was wide whereas instep height was average. In regards to the metamorphic parts of foot, the most metamorphic part was the fifth toe which could be occurred by disagreeable shoes to foot. 2. General salary men (69.5%) wear the formal shoes and their wearing time per day is over 10 hours (49%), which illustrates that more suitable and convenient functional shoes needs to be developed. 3. Almost of subjects tended to purchase ready-made shoes, and their concerns to be considered when to purchase ready-made shoes were its size and solidity. This finding suggests that the size specification of the ready-made shoes needs to be more specific in terms of its length as well as foot breadth. 4. The most unsatisfied point on the ready-made shoes was the foot breadth. According to the Crosstabulation analysis on the discomfort part and the foot breadth, there existed a significant correlation between the discomfort part and the foot breadth (p$\leq$0.05). The above results make clear that overall salary men have complaints on the ready-made formal shoes in terms of its size and wearing comfort level. This suggests that the subdivision of the shoes size specification needs to be developed to improve the wearing comfort level.

• 대한산업공학회지
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• 제14권2호
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• pp.71-80
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• 1988

The primary purpose of this study is to develop an automation tool capable of converting the specification of structured analysis into that of structured design. Structured Analysis and Structured Design Language (SASDL) is a computer-aided description language based on ERA model and particulariged by ISLDM/SEM. The automation tool utilizes the specifications of data flow diagram described in SASDL to produce their corresponding SASDL specification of structure chart. The main idea behind the automatic conversion process is to categorize the bubbles in data flow diagram and to determine the positions of the bubbles in structure chart according to their categories and the relative locations in data flow diagram. To make the problem into manageable size, the whole system is broken down into separate parts called activity units. A great deal of manual jobs, such as checking processes leveling, checking data derivation of processes, deriving structure chart from data flow diagram, checking any inconsistency between data flow diagram and structure chart and so forth, can be automated by using SASDL and conversion tool. The specification of structure chart derived by conversion tool may be used in an initial step of design to be refined by SASDL users.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기설비전문위원
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• pp.39-43
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• 2005

There are big differences between developed countries and Korea regarding to the circumstances of electrical installation construction. In other words, Korea, in spite of its small market size, has large pools of electrical construction companies or associated workers, and there are a lot of poorly electrical construction companies in domestically. Thus, in reality, it is difficult to invest in technical development to enhance Korea's technical level on electrical installation and companies are likely to construct as occasion demands instead of constructing in a technical manner. Therefore, the government needs to develop a standard specification as a guideline for stable, economical and technical electrical installation construction. With this standard specification, almost all electrical construction companies could practically use it and also could guarantee their construction quality as well. It is important to induce small companies to utilize the standard specification to secure their construction excellent quality so that the life of the nation, individual's properties and national properties could be well protected.

• 한국의류산업학회지
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• 제15권2호
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• pp.247-255
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• 2013

This study develops size sections and specifications for females 7-18 years old. The specifications will contribute to the development of precise virtual models that represent basic data for the size alteration of 3D virtual models. A total of 33 items from the $5^{th}$ Size Korea data set were adopted and analyzed. Two representative factors (Obesity and Height Factors) were identified through a factor analysis of the 33 items. Waist circumference and stature were selected as representative variables for Obesity and Height Factors, respectively, and conducted cross tabulations between waist circumference and height for the age groups of 7-12 and 13-18 year-olds. Size sections were developed for the development of 3D models based on the results. A regression analysis then developed size specifications for each section with independent variables of waist circumference and height as well as dependent variables of reference body size. Subsequently, Obesity Factors were better explained by waist circumference and Height Factors were better explained by stature. Finally, size specifications for each section were developed.