Force Control of Hybrid Actuator Using Learning Vector Quantization Neural Network

Aan Kyoung-Kwan,Chau Nguyen Huynh Thai The Korean Society of Mechanical Engineers 2006 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.20 No.4

Hydraulic actuators are important in modern industry due to high power, fast response, and high stiffness. In recent years, hybrid actuation system, which combines electric and hydraulic technology in a compact unit, can be adapted to a wide variety of force, speed and torque requirements. Moreover, the hybrid actuation system has dealt with the energy consumption and noise problem existed in the conventional hydraulic system. Therefore, hybrid actuator has a wide range of application fields such as plastic injection-molding and metal forming technology, where force or pressure control is the most important technology. In this paper, the solution for force control of hybrid system is presented. However, some limitations still exist such as deterioration of the performance of transient response due to the variable environment stiffness. Therefore, intelligent switching control using Learning Vector Quantization Neural Network (LVQNN) is newly proposed in this paper in order to overcome these limitations. Experiments are carried out to evaluate the effectiveness of the proposed algorithm with large variation of stiffness of external environment. In addition, it is understood that the new system has energy saving effect even though it has almost the same response as that of valve controlled system.

ON THE WEAK LAW OF LARGE NUMBERS FOR SEQUENCES OF BANACH SPACE VALUED RANDOM ELEMENTS

Quang, Nguyen Aan,Son, Le-Hong Korean Mathematical Society 2006 대한수학회보 Vol.43 No.3

We establish a weak law of large numbers for sequence of random elements with values in p-uniformly smooth Banach space. Our result is more general and stronger than some well-known ones.

알파고(인공지능)의 번역 불가능성과 디지털 바벨탑의 붕괴

안진국(Lev Aan) 한국콘텐츠학회 2016 한국콘텐츠학회지 Vol.14 No.2

논문 : 지각하는 몸의 원리: 미하일 체홉의 제스처 -현상학적 관점을 통한 배우와 역할 사이의 거리와 캐릭터 창조

안정민 ( Jeong Min Aan ) 한국연극교육학회 2015 연극교육연구 Vol.27 No.-

This study is aiming to discover the theatricality of Michael Chekov’s Psychological Gesture, especially its role of making distance between the individuality of actor and character. Phenomenological scope will be adapted in order to find the principle underpinning Chekov’s actor training system. For Michael Chekov, actor’s skill is not about acting character, but about acting the atmosphere of character. Hence, actor is not a person who tries to incarnate character either logically analyses it. Instead, he/she presents the body perceiving atmosphere and evoking it simultaneously. Here, the need of Psychological Gesture arises. It is the body that keeps adjust itself in order to perceive the atmosphere more precisely. From phenomenological sense experience yielded by altering and discovering Gestures, actor’s feeling and will power which moves toward action initiate. Psychological Gesture also creates the distance between individual physicality and the character which will not be acted by actors but will be phenomenologically signified by them. Situating psychological gesture as phenomenological sensing body creates the meaning generating loop with making the texture, colour of meanings and physicality of actors deepened and enhanced. In addition, this loop invites audience as co-creator of performance, since actor in the movement of gestures ‘signifies’ the layers of atmosphere and energy of characters rather than represents or semiotically depicts them. In this process, audiences posit themselves as the subject who completes the signified according to the sense experience from the configuration of signifiers. This inter-subjectivity amongst actors and audience lets character occur as a situation does. Hence, for Michael Chekov, character is not a product but byproduct or finding which only exists in-between, in the phenomenological relationship. Encompassing the basic terms of Chekov from the view of phenomenology, it will be seen that his acting theory is the determination of embracing literature with theatricality and re-situating it as the field of atmosphere which inspires theatre creators.

아름다운 環境創造의 굳건한 터전을 : 「터전」誌의 創刊에 즈음하여 As the Movement of the Foundation of a New Journal-Topos

金安濟 서울대학교 환경대학원 부설 환경계획연구소 1988 터전 Vol.1 No.-

자연물과 인공물로 구성된 인간환경은 우리 모두의 삶을 존립케 하는 원천적 터전이요, 인간의 활동을 가능케 하는 필수적 요건이다. 인간은 그의 삶과 생산 및 활동을 영위하고 또 더욱 편의롭게 하기 위해 자연의 모습을 변형시키고 새로운 인공물을 건설하게 되며, 이러한 인간행위는 인류역사와 더불어 이루어져 왔고 인구의 증가와 활동의 확대에 비례하여 한층 더 활발해 지게 되었다. 더욱이 산업화와 도시화에 따른 인간환경의 변혁은 괄목할 만큼 심화되었고 앞으로의 변화는 더욱 가중되어 갈 것으로 전망되고 있다. 인간환경이 갖는 자연성과 인위성이라는 두개의 성격은 우리로 하여금 바람직한 환경을 조성하고 아름다운 공간을 창조케 하는 필요성과 가능성을 제공해주고 있다. 여기에 쾌적하고 능률적이며 아름다운 환경을 만들기 위한 계획과 설계의 당위성이 있는 것이다. 환경의 계획 및 설계는 이론과 실제의 결합을 어느 분야보다도 가장 강하게 요구하고 있다. 실제의 적용으루부터 새로운 이론이나 기법이 도출 또는 발전 되고, 개발된 새로운 이론이나 기법을 현실에 적용함으로써 실제의 계획 및 설계를 발전시키게 된다. 이와같은 이론과 실제의 상호수수작용과 귀납 · 연역과정을 통해 계획이나 설계는 개선되고 발전되어 가는 것이다.

Nanosulfated Silica as a Potential Heterogeneous Catalyst for the Synthesis of Nitrobenzene

Khairul Amri,Aan Sabilladin,Remi Ayu Pratika,Ari Sudarmanto,Hilda Ismail,Budhijanto,Mega Fia Lestari,오원춘,Karna Wijaya 한국재료학회 2023 한국재료학회지 Vol.33 No.7

In this study, the synthesis of nitrobenzene was carried out using sulfated silica catalyst. The study delved into H2SO4/SiO2 as a solid acid catalyst and the effect of its weight variation, as well as the use of a microwave batch reactor in the synthesis of nitrobenzene. SiO2 was prepared using the sol-gel method from TEOS precursor. The formed gel was then refluxed with methanol and calcined at a temperature of 600 °C. SiO2 with a 200-mesh size was impregnated with 98 % H2SO4 by mixing for 1 h. The resulting 33 % (w/w) H2SO4/SiO2 catalyst was separated by centrifugation, dried, and calcined at 600 °C. The catalyst was then used as a solid acid catalyst in the synthesis of nitrobenzene. The weights of catalyst used were 0.5; 1; and 1.5 grams. The synthesis of nitrobenzene was carried out with a 1:3 ratio of benzene to nitric acid in a microwave batch reactor at 60 °C for 5 h. The resulting nitrobenzene liquid was analyzed using GC-MS to determine the selectivity of the catalyst. Likewise, the use of a microwave batch reactor was found to be appropriate and successful for the synthesis of nitrobenzene. The thermal energy produced by the microwave batch reactor was efficient enough to be used for the nitration reaction. Reactivity and selectivity tests demonstrated that 1 g of H2SO4/SiO2 could generate an average benzene conversion of 40.33 %.

인성과 행복의 통합 교육프로그램 수강과 실행을 통한 영유아교사의 인식 질적 연구

장희선(Chang, Heesun),안영진(Aan, Young-Jin) 한국영유아보육학회 2017 한국영유아보육학 Vol.0 No.103

본 연구에서는 영유아교사들이 인성과 행복의 통합 교육프로그램을 수강 후, 영유아 교육 기관에서 인성과 행복교육 프로그램을 직접 실행함으로써 영유아교사들의 영유아 인성과 행복교육에 대한 인식이 어떻게 변화했는지 살펴보고자 하였다. 이를 위해 영유아교사들은 인성과 행복의 통합 교육프로그램을 수강하고, 영유아의 배려 · 약속 · 정직 등의 인성 덕목 행동개선과 행복을 위한 효과적인 교수학습활동을 8차시 이상에 걸쳐 실행하도록 하였다. 이후 영유아 인성과 행복의 통합 교육 프로그램 실행 전과 실행 후 영유아 교사의 인식변화를 살펴보기 위해 성찰일지, 교수-학습지도안, 개별면담, 전문가협의회(FGI) 등을 통해 모은 자료를 코딩하여 질적 분석을 실시하였다. 연구결과는 다음과 같다. 첫째, 영유아교사에게 내재적 동기변화가 나타났다. 교사들은 프로그램을 수강하고 실행하면서 일어난 영유아의 인성과 행복감의 변화가 교사 자신의 행복감에 영향을 미치게 되는 선순환 구조임을 인식하게 되었다. 둘째, 영유아교사에게서 교육전문성향상에 대한 자율적 적극성이 나타났다. 영유아교육현장에서 기존 교육과정을 재구성하여 적용하였고, 인성과 행복교육방법 및 자료 개발의 필요성을 인식하는 등의 변화를 보였다. 셋째, 영유아교사들과 영유아들의 가정 및 교육관계자와 공동체의식이 함양되었다. 즉, 영유아인성과 행복의 통합적 교육에 대해 영유아들이 인성과 행복의 방향과 가치를 바르게 이해하게 해주고, 일관성 있는 교육이 지속될 수 있는 영유아 교육기관과 가정 공동체의 상호보완적인 과정이 되어야 한다는 인식을 하게 되었다. 본 연구는 영유아교사가 보다 의미 있고 효과적으로 영유아 인성과 행복교육을 실행할 수 있기 위해서는 영유아교사의 인성과 행복의 변화뿐아니라 교육기관, 가정의 공동체적 협동적 지원이 동시에 필요함을 시사한다. In this study, early childhood teachers were asked to apply a character and happiness education program for young children at the institution that they served and to implement an effective method for improving young children’s character such as care, promise, honesty, and happiness. Through this, we investigated the change of early childhood teacher’s perception before and after the character and happiness education program for young children. The results were as follows. First, the change of children’s character and happiness had an effect on teachers’ happiness, which was a virtuous circle. Second, teachers reconstructed existing curriculum in the field of early childhood education and perceived that it was necessary to develop the educational methodology and materials for character and happiness. Third, teachers perceived that early childhood educational organizations and the home environment encouraged young children to understand the direction and values of character and happiness correctly, and that consistent education is needed. This study implies that there needs to be support for early childhood teachers in order to educate young children on character and happiness more meaningfully and effectively.

Multi-objective Mathematical Modeling for Scheduling Machines in Parallel with Batch Processors

Evy Segarawati Ampry,Aan Komariah,Dedy Achmad Kurniady,Muhammad Rafiq,Asep Priatna,Muneam Hussein Ali,Haydar Abdulameer Marhoon,Lakshmi Thangavelu,Purnima Chaudhary 대한산업공학회 2022 Industrial Engineeering & Management Systems Vol.21 No.2

In this paper, the problem of scheduling the production of unrelated parallel machines to simultaneously minimize the goals of production time span, early and late fines, and the cost of purchasing machines is investigated, and a two-objective mathematical model is considered considering clearance and preparation times and limit capacity. Due to faster and cheaper operations with batch processors and increasing the efficiency of operating systems, all machines are batch processors. Initially, the model is coded and executed using the exact method in GAMS software. Due to the hard-NP nature and complex nature of the problem, a multi-objective meta-heuristic algorithm based on the coordination search method is proposed and designed. Then Taguchi method is used to find the best level for the algorithm parameters, and two examples of problems in different dimensions of tasks and machines are presented and solved by this proposed algorithm. The results of the calculations show the efficiency of this algorithm to generate more solutions at a much lower solution time.

Disposal and Treatment for Decommissioning Solid Waste of Advanced Fuel Science Building at KAERI

Byungyoun Min,Hyojin Aan,Undong Choi,Jinho Park,Seungkook Park 한국방사성폐기물학회 2020 한국방사성폐기물학회 학술논문요약집 Vol.2020 No.12

Optimization of ergosterol to vitamin D₂ synthesis in Agaricus bisporus powder using ultraviolet-B radiation

Lee, Nam Keun,Aan, Byung-Yong 한국식품과학회 2016 Food Science and Biotechnology Vol.25 No.6

Response surface methodology (RSM) was applied to determine the optimum circumstances for conversion of ergosterol to vitamin $D_2$ via ultraviolet-B (UV-B) in white button mushroom (Agaricus bisporus) powder. Three independent variables, namely, exposure time, ambient temperature, and irradiation intensity were investigated using a central composite rotatable design. The RSM ridge analysis determined the following ideal states: exposure time of 10.4 min, ambient temperature of $26.33^{\circ}C$, and UV-B irradiation intensity of $1.36W/m^2$. A vitamin $D_2$ content of $741.50{\pm}23.75{\mu}g/g$ (the predicted value was $780.4{\mu}g/g$) was obtained under these ideal conditions.