우주항공 재료시스템 품질인증

이호성,Lee, Ho-Sung 항공우주시스템공학회 2007 항공우주시스템공학회지 Vol.1 No.2

Structural qualification plan (SQP) for aerospace vehicle is based on material certification methodology, which must be approved by certification authority. It is internationally required to use of statistically based material allowables to design aerospace vehicles with aerospace materials. In order to comply with this regulation, it is necessary to establish relatively large amount of database, which increases test costs and time. Recently NASA/FAA develop the new methodology which results in cost, time, and risk reduction, and satisfies the regulation at the same time. This paper summarizes the certification methodology of materials system as a part of structural qualification plan (SQP) of aerospace vehicles and also thermal management of the vehicle system, like thermal protection materials system and thermally conductive material system. Materials design allowable was determined using this method for a carbon/epoxy composite material.

초소성 및 확산접합을 이용한 우주항공 부품 성형기술 개발

이호성,윤종훈,이영무,Lee, Ho-Sung,Yoon, Jong-Hoon,Yi, Yeong-Moo 한국군사과학기술학회 2005 한국군사과학기술학회지 Vol.8 No.3

In this paper, a near net shape technology using superplasticity and diffusion bonding characteristics was presented for application to various components of aircraft and missiles. Due to these special characteristics of some aerospace alloys, it is possible to produce complex components to shape very near final dimension with enhanced design freedom, reduced material usage, and overall saving of weight and cost. The high pressure vessel for a space launcher was fabricated with Ti-6Al-4V alloy by superplastic forming and diffusion bonding process and the failure characteristics are compared with conventionally fabricated vessel spin formed and TIG welded. The structural integrity of the superplastic forming and diffusion bonding process was successfully demonstrated.

무장애 주택설계에 관한 국내외 국가표준의 비교 연구 -현관, 침실, 거실을 중심으로

이호성,최찬환,이특구,Lee, Ho Sung,Choi, Chan-Hwan,Lee, Teuk-Koo 한국의료복지건축학회 2010 의료·복지 건축 Vol.16 No.1

This is a comparative study mainly on foreign countries' domestic standards and laws on barrier free housing construction that can be applied to the dwelling of elderly friendly apartment housing. Eight countries - the United States, Germany, Canada, Switzerland, the United Kingdom, Australia, Japan, and China - were reviewed as foreign cases. The analyzed subjects were design standards only for the disabled and the aged. To compare barrier-free guides of the eight countries, each barrier-free guide on three space units (entrance, bedroom, living room) was divided into 11 design items and 36 design factors. The comparative analysis on foreign cases was based on the design guide according to Korea's KS P 1509 (principle and recommendation for designing dimension of dwelling in consideration of the elderly). Some factors -if with dimensions- were compared by means of the skewness of distribution. In the analysis result, there were not only common standards for the nine countries such as a dimension of the space for wheelchair movement but also different standards such as heights of outlets and horizontal lengths of bathtub grab bars. The detailed analysis shows that it is urgently necessary to prepare new domestic national design standards for 8 factors that foreign countries already have. It is also needed to immediately prepare dimension standards for the design factors, which have no detailed dimensions but only national guides, in consideration for anthropometric dimension.

남한 예비교사의 북한 화학 교과서에 제시된 과학 용어 이해

이호성,노봉오,박현주,Lee, Ho-Sung,Ro, Bong-Oh,Park, HyunJu 대한화학회 2008 대한화학회지 Vol.52 No.6

유도무기용 날개구동기의 동적 강성 측정을 위한 유압 구동장치의 토크제어 기법에 관한 연구

이호성,Lee, Ho-Sung 한국군사과학기술학회 2007 한국군사과학기술학회지 Vol.10 No.3

This paper presents a torque control method of a hydraulic actuation system for measuring the dynamic stiffness of missile fin actuators. We propose a new control technique called Dual Dynamic Torque Feedback Control(DDTFC), which improves the stability of the torque control system and enables fast tracking of torque command. The developed control scheme is derived from the physical understanding based on mathematical modelling and analysis. The dynamics of hydraulic torque control servo-system is unravelled via physics-based modelling and nonparametric system identification. In order to verify the effectiveness of the method, the experiment is carried out with a test equipment for measuring the dynamic stiffness. The experiment and simulation results show that DDTFC gives stability improvement.

퍼지확률회귀모형(確率回歸模型)

이호성,오창혁,Lee, Ho-Sung,O, Chang-Hyeok 한국데이터정보과학회 1994 한국데이터정보과학회지 Vol.5 No.1

기존의 퍼지회귀모형은 모수의 퍼지성질에 의해 관측된 종속변수의 변동을 설명하는 방법이다. 그러나 일반적으로 종속변수에 영향을 미치는 모든 독립변수를 모형화하는 일은 불가능하므로 종속변수가 삼각퍼지숫자로 관측된 경우 모형화되지 않은 변수들의 영향을 랜덤 오차항으로 두는 퍼지확률회귀모형을 소개하고 이에 따른 모수추정법을 다룬다. 이 방법은 통계적 회귀모형의 일반화로 간주할 수 있다.

Ti-6Al-4V 샌드위치 패널제작을 위한 초소성/확산접합 기술개발

이호성,윤종훈,이승철,박동규,이영무,Lee, Ho-Sung,Yoon, Jong-Hoon,Lee, Seung-Chul,Park, Dong-Kyu,Yi, Yeong-Moo 한국군사과학기술학회 2008 한국군사과학기술학회지 Vol.11 No.3

Ti-6Al-4V alloy is a critical strategic metal used in aerospace structure due to the high specific strength, toughness, durability, low density, corrosion resistance. Examples of application of this alloy are airframe structural components, aircraft gas turbine disks and blades. Forming of this alloy is not easy due to its high strength and low formability. However, this alloy shows superplastic properties that allow for large plastic deformation under certain conditions. Combination of superplastic forming and diffusion bonding(SPF/DB) processes of this alloy has been widely used to replace mechanically fastened structures with reduced weight and fabrication costs. In this study, superplastic forming/diffusion bonding technology has been developed for fabricating lightweight sandwich panels with Ti-6Al-4V alloy. The experimental results show the forming of titanium lightweight sandwich structure is successfully performed from 3 and 4 sheets of Ti-6Al-4V.

한국의 초고령사회를 대비한 최소주거면적 기준의 인체측정학적 방법 연구 - Karl H. E. Kroemer의 인체측정학적 데이터 적용 방법 -

이호성,Lee, Ho Sung 한국의료복지건축학회 2017 의료·복지 건축 Vol.22 No.3

Purpose: Korea is expected to enter an aged society in 2018 and then a super-aged society in early 2025. The country's aging is progressing faster than any other country in the world. However, the foundation of the elderly friendly industry is weak, and measures at the government level are urgently needed. Especially, housing problems of the elderly are one of the most urgent measures to be taken. Korea does not have the minimum residential area standard for the elderly, and the current general minimum residential area standard is based on the survey of the housing situation without scientific evidence. Therefore, both standards need to be revised as soon as possible based on scientific evidence. Methods: The minimum residential area standard has been calculated following Karl H. E. Kroemer's Min or Max design also being called as-single cut and dual cut theory- as the maximum population value and minimum population value theory of Ernest J. McCormick. Therefore there is a need for a formula made using a few key factors, such as corresponding dimension, practical dimension, clearance, spare dimension, integrated dimension. These elements can be defined and used as formulas to calculate minimum residential area standards. Results: Assuming the results of the spatial variability in this study showed that it is possible to raise the standard of living in a terms of sustainable minimum size for the young, old and all residents. Implications: The government should set a minimum residential area standard with scientific grounds and set up a policy improving the life of people who live in an needy residential environment.

선진국형 의료·복지 건축을 위한 제언

이호성(Lee, Ho Sung) 대한건축학회 2022 建築 Vol.66 No.5

디자인 분석 모델의 최적화 과정에 관한 연구 - 소비자 선호도 조사를 중심으로 -

이호성(Ho Sung Lee),윤현노(Hyun No Yun),한정완(Jung Wan Han) 한국디자인과학학회 2001 디자인과학연구 Vol.4 No.2

소비자의 감성에 맞는 제품을 만드는 문제에 접근하는데 있어 기업들은 많은 방법론을 연구하고 있지만 감성이라는 자체가 워낙 애매하고 주관적인 형태를 가지고 있어 접근 방법에서도 주관적이고 감성적일 수 밖에 없었다. 또 제품의 품질과 기능의 향상을 위해 연구하던 기존의 시스템은 객관적이고 과학적인데 반해 소비자들의 감성은 주로 주관적이고 형태가 애매하며 유동적인 특성을 가지고 있어 이러한 요소들을 객관화시키고, 정량화 할 필요성이 요구된다. 이를 해결하기 위한 방법으로서 등장한 것이 감성공학이며 인간의 심리적인 요소를 분석하고 정량화하여 이를 제품의 설계에 필요한 기본적인 물리적 디자인 요소들과 유기적인 관계를 맺어주어 최종적으로 제품 형태를 이루게 만드는 방법이다. 아직 이 연구는 초기 단계라서 그 연구의 형태가 확실한 모양을 갖춘 것은 아니지만 지금까지의 연구진행과정으로 볼 때 감성공학은 차후의 다른 기술 개발과 퍼지이론, 인곤 신경망 이론, 인공 현실감과의 깊은 연관성 및 응용성을 갖고 있다는 점이 또 다른 매력인 것 같다. 현재는 소비자 개개인의 개성에 따라 차별화와 자기표현 지향이 표면으로 나타난 시대라고 할 수 있으며 또한 사람들의 요구수준이 급속도로 개성화, 고도화되고 있다. 기능, 성능, 가격 등의 물리적인 편의성은 상품이 지질 기본적인 요소로 취급되고 쾌적성, 편리성, 자신의 개성만족, 전체적 조화성 등의 정서적인 면에서의 부가가치가 중요시되고 있다. 따라서 본 연구는 디지털환경이 요하는 새로운 기획분석모형을 체계화시켜 디자이너로 하여금 주체적인 역할을 수행할 수 있도록 설정하였다. Companies are looking for methods of making products which conform with emotion and are making know-hows in their own ways. However emotion itself is so ambiguous and subjective that its approaching method cannot avoid being subjective and emotional. The existing system for improving the quality and function is objective and scientific while the customers` senses are mainly subjective and have ambiguous and changeable features. Therefore, a medium as a translator between the two aspects is needed. Sensitivity engineering has appeared in order to solve it, which analyzes human psychological factors and quantify them, then org-anically connects them with fundamental physical design factors for product design to make final form of a product. This field of study is still in its infancy and its form is rather incomplete. However, in the aspect of the direction and method of the study, sensitivity engineering can be said to have an attraction as it is deeply related with future technology development and fuzzy theory, artificial neural net theory and artificial reality as well as applicability. Today, difference of personalities and self-expression of individual consumers are getting shown on the surface. The level of their demands is rapidly individualizing and sophisticating. Physical con-venience such as function, performance, and price is treated as basic factor a product has to have, while emotional factors such as comfort, handiness, individual satisfaction and entire harmony are becoming more important. In order to conform with those changing demands of consumers, products which reflect human sense are being developed now.