• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2001년도 추계학술대회논문집 I
• /
• pp.52-57
• /
• 2001

In this paper, the optimum designs of air-bearing surface(ABS) are achieved effectively by using reduced basis concept which can reduce the number of design variables although the design space is distended. Generally, the optimization method is more effective than the trial and error. However, the efficiency of the former is largely dependent on the number of the design variables. In order to reduce the number of design variables and increase the efficiency, reduced basis concept is applied. We can define the desired design as a linear combination of basis designs using this concept. From this optimization method with reduced basis concept, we easily obtain the optimum designs of ABS whose target flying heights are 25, 20, 15 nm.

• 대한기계학회논문집A
• /
• 제27권3호
• /
• pp.343-348
• /
• 2003

In this study, optimum designs of the air-bearing surface (ABS) are achieved using the reduced basis concept which can effectively reduce the number of design variables without cutting down on the design space. Even though the optimization method is easier and more applicable to handle than the trial-and-error method, its efficiency is largely dependent on the number of the design variables. Hence, the reduced basis concept is applied, by which the desired design can be defined as a linear combination of basis designs. The simulation results show the effectiveness of the proposed approach by obtaining the optimum solutions of the sliders whose target flying heights are 25, 20, and 15nm.

• 대한전자공학회논문지
• /
• 제15권1호
• /
• pp.12-18
• /
• 1978

Roome6)은 주어진 상태표로부터 최눈 k-CC를 구하고 이로 부터 k-SR의 종분할인 요소분할을 구하는 알고리즘을 제시하였다. 본 논문은 단순히 비트의 비교와 처리만으로 기본분할을 구할 수 있고 계산기 프로그램에 용이한 보라 개선된 두 알고리즘을 제시하였다. 기저분할의 쌍이란 개념을 정의하였고 이것을 이용함으로서 주어진 기저분할의 집합이 기저분할의 쌍의 요소만을 갖게되어 알고리즘이 간단화 되었다.

• 시큐리티연구
• /
• 제50호
• /
• pp.287-303
• /
• 2017

산업보안 관련 연구는 지난 10여 년 간 빠르게 증가하는 추세를 보이고 있다. 산업보안 관련 학회가 만들어지고, 대학에 산업보안학과가 신설되면서 산업보안에 대한 학문적 관심과 연구 또한 빠른 속도로 확산되고 있다. 이와 같이 학문적 관심과 연구가 양적으로 크게 성장한 반면에 학문적 체계화의 기초가 되는 이론 분야에 대한 연구는 극히 미미한 실정이다. 개념화를 비롯한 이론적 바탕에 대한 고민 없이 특정 현안에 대한 문제 제기와 실무적인 해결 방안 제시에만 관심이 집중되어 있는 형편이다. 때문에 대부분 연구에서 산업보안 개념은 선행연구에서 적용한 개념을 그대로 수용하는 수준에 머물러 있다. 산업보안 연구 대부분이 '산업기술보호'라는 특정 주제로 집중된 이유가 산업보안 개념을 산업기술보호로 축소해 간주하고 있기 때문이다. 산업보안은 매우 다양한 영역과 분야로 이뤄져 있음에도 특정 분야를 산업보안의 전부로 인식하는 것은 매우 심각한 문제가 아닐 수 없다. 이로 인해 산업보안 연구에서 산업보안 개념은 모호하고 부정확하고 편의적으로 사용되고 있는 상황이다. 산업보안 개념을 논리적 명확성과 경험적 타당성에 근거하여 정확하고 히 인식하여 제시할 필요가 있는 것이다.

• 한국초등과학교육학회지:초등과학교육
• /
• 제35권3호
• /
• pp.377-387
• /
• 2016

Whether textbooks faithfully reflect the curriculum contents is an important educational issue. The previous studies on the textbooks did not analyze the relationship described in the textbooks or the structure. In this regard, this study aims to analyze how the concept of life science area in the elementary school science textbooks developed on the basis of the 2009 revised curriculum is linked. In addition, it seeks to analyze how the concept presented in the learning content achievement standards of the curriculum is connected to other concepts. Towards this end, the conceptual linkage of eight units in the life science domain of elementary school science textbooks based on the 2009 revised curriculum was analyzed. The contents of the life science domain in the science textbooks were analyzed through a semantic network analysis, and the semantic network on the concept linked to the one described in curriculum's learning objectives was also analyzed. The results are as follows: 1) It will be difficult for students to understand the concept due to the complexity of the semantic network resulting from a number of concepts. 2) The curriculum's learning objectives presented in the curriculum are not faithfully reflected in the textbooks. 3) The textbooks are described on the basis of specific curriculum's learning objectives. Based on the findings of this study, the number of concepts described in the elementary school science textbooks needs to be significantly reduced so that the concepts can be meaningfully linked to each other.

• 사회경제평론
• /
• 제31권3호
• /
• pp.165-201
• /
• 2018

프리드리히 니체와 앨프레드 화이트헤드에 따르면, 근대 서양의 존재론이 범한 치명적인 오류는 현실의 구조가 언어의 구조와 같다고 착각하는 데 있다. 언어는 주어-술어 구조를 띠고 있는데, 현실도 이 구조를 띠고 있다고 착각해서, 허구적인 언어적 주어를 현실적으로 존재하고 있는 주체로 잘못 설정하고 있다. 이 허구적인 주체 개념이 바로 인격 개념이다. 본 논문은 이러한 허구적인 인격 개념이 어떻게 자본주의 금융이 발전하는 데 토대를 이루는지 분석할 것이다. 본 논문의 분석하는 역사적 시기와 장소는 17세기 후반 영국이다. 이 시기에 영국에서 근대적 형태의 은행업이 시작됐으며 동시에 근대적 주체 개념인 "인격" 개념이 존 로크 등에 의해 철학적으로 발전한다. 동시에 유한책임 주식회사와 국가 또한 독립적인 추상적 인격성이 추상적인격체로 독립성을 획득한다. 이 추상적 인격 개념은 사회적 관계를 "배타적 소유"와 "채권-채무" 관계로 환원하고, 이 환원이 근대 금융의 존재론적 바탕을 이룬다. 배타적 재산권은 행사하지만 책임을 져야 할 때는 채권으로 변모해 그 책임을 회피하는 제도가 바로 근대 금융의 본질이다. 그리고 영원하고 독립적인 인격성을 지니게 된 근대적 집단을 채무자로 전락시킴으로 근대 금융의 채권자들은 자신들의 특권을 크게 강화한다.

• Tribology and Lubricants
• /
• 제4권1호
• /
• pp.43-55
• /
• 1988

A Study on the effect of the additives in lubricating oil was investigated on the basis of the thermal activated wear theory in terms of their wear behaviours, using four ballwear machine. The sample oils, which included diethyl-3, 5-di-t-butyi-4-hydroxy-benzyl phosphonate (DEP), ZDDP and TCP additives respectively, showed distinct wear characteristics depending upon the bulk oil temperature and the sliding velocity. The newly synthesized additive, viz., DEP showed excellent antiwear performance cornpared with the conventional additives, ZDDP and TCP. On the basis of the experimental results, it is reduced that the wear mechanism of the conventional additives, viz., ZDDP and TCP is the protective film formation and their antiwear capability is depending upon the shearing strength of the film formed. On the other hand, the new additive, DEP showed that the secondary activation energy was much eliminated and so, the thermal instability was reduced by the hydrogen scavenging reaction of the new additive, which was virtually an endothermic reaction process.In conclusion, a new concept of antiwear mechanism is estabilished and testified. And new chemical, which showed the function of hydrogen and free radical scavenging role, is synthesized and introduced as the new, highly antiwear effective lubricating oil additive.

• 동아시아경상학회지
• /
• 제12권2호
• /
• pp.43-50
• /
• 2024

Purpose: The present study investigates if the type of organizational culture influences the level of job-related stress. This study is significant because creating the need to explore the concept to become more informed on the best practices to promote and foster a positive culture that prioritizes workers, it could result in a healthier workforce, improved organizational performance, and success. Research design, data and methodology: Examining previous studies by other researchers was the primary research tool for this study. The organized approach of gathering data and assessing related work was vital in developing a fundamental basis for advancing knowledge on this concept while enhancing theory development and drawing more informed conclusion. Results: These four types, including the clan, adhocracy, hierarchical, and market cultures, contribute significantly in revealing four associations between the two variables, including (i) supportive culture and reduced stress, (ii) high pressure and increased stress, (iii)autonomous culture and variable stress levels, and (iv) open culture and low-stress levels. Conclusions: The literature affirms a multifaceted link between employee workplace stress and organizational culture type. The findings show that these cultures are crucial in influencing the level of stress among employees. All four types were hypothesized to have a significant relationship with job stress.

• Steel and Composite Structures
• /
• 제34권5호
• /
• pp.671-679
• /
• 2020

The new energy-based criterion, named Reinforcement Strain Energy Density (ReiSED), is proposed to investigate the fracture behavior of the cracked orthotropic materials in which the crack is embedded in the matrix along the fibers. ReiSED is an extension of the well-known minimum strain energy density criterion. The concept of the reinforced isotropic solid as an advantageous model is the basis of the proposed mixed-mode I/II criterion. This model introduces fibers as reinforcements of the isotropic matrix in orthotropic materials. The effects of fibers are qualified by defining reinforcement coefficients at tension and shear modes. These coefficients, called Reduced Stress (ReSt), provide the possibility of encompassing the fiber fraction in a fracture criterion for the first time. Comparing ReiSED fracture limit curve with experimental data proves the high efficiency of this criterion to predict the fracture behavior of orthotropic materials.

• Journal of Mechanical Science and Technology
• /
• 제18권1호
• /
• pp.37-44
• /
• 2004

This paper presents an approach to optimally design the air bearing surface (ABS) of the head slider by using the approximation methods. The reduced basis concept is used to reduce the number of design variables. In the numerical calculation, the progressive quadratic response surface modeling (PQRSM) is used to handle the non-smooth and discontinuous cost function. A multi-criteria optimization problem is formulated to enhance the flying performances over the entire recording band during the steady state and track seek operations. The optimal solutions of the sliders, whose target flying heights are 12 nm and 9 nm, are automatically obtained. The flying heights during the steady state operation become closer to the target values and the flying height variations during the track seek operation are smaller than those for the initial one. The pitch and roll angles are also kept within suitable ranges over the recording band.