• 한국공작기계학회논문집
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• 제18권2호
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• pp.144-153
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• 2009

It is widely known that no-slip assumptions are often violated on regular basis in micrometer- or nanometer-scale fluid flow. In the case of cavity-filling process of nanoimprint lithography(NIL), slip phenomena take place naturally at the solid-to-liquid boundaries, that is, at the mold-to-polymer or polymer-to-substrate boundaries. If the slip or partial slip phenomena are promoted at the boundaries, the processing time of NIL, especially of thermal-NIL which consumes more tact time than that of UV-NIL, can be significantly improved. In this paper it is aimed to elucidate how the cavity-filling process of NIL can be influenced by the slip phenomena at boundaries and to what degree those phenomena increase the process rate. To do so, computational fluid dynamics(CFD) analysis of cavity filling process has been carried out. Also, the effect of mold pattern shape and initial thickness of polymer resist were considered in the analysis, as well.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2005년도 춘계학술대회 논문집
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• pp.401-406
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• 2005

According to the ubiquitous times that is new important topic, the miniature is demanded in the industry at large. The high accuracy and accumulation make the assembly equipment and the production equipment huge from the size of view. The huge equipment brings about the expensive price of the equipment, a low flexibleness and a low productivity. It makes the manufacturing equipment huge that the accuracy only depends on the mechanism stiffness. The position of two assembled parts is transformed with the global coordinate system whose datum is machine coordinate system. The purpose of this research is invention of the module that can adjust one part to the order part automatically. The module that has a function of self adjustment only takes a stiffness in assemble direction and can be moved freely in the other direction so this function makes a self adjustment. The self adjustment module reduces the tact time and also diminishes the inferior goods and makes reconfigurable machine in $\mu-part$ assembly.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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• pp.20-25
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• 1998

This paper proposes a new compliant contact control strategy for the robot manipulators accidentally interacting with an unknown environment. The main features of the proposed method are summarized as follows: First, each entry in the diagonal stiffness matrix corresponding to the task coordinate in Cartesian space is adaptively adjusted during con-tact along the corresponding axis based on the contact force with its environment. Second, it can be used for both unconstrained and constrained motions without any switching mechanism which often causes undesirable instability and/or vibrational motion of the end effector. Third, the adjusted stiffness gains are automatically recovered to initially specified stiffness gains when the task is changed from constrained motion to unconstrained motion. The simulation results show the effectiveness of the proposed method by employing a two-link direct drive manipulator interacting with an unknown environment.

• 한국시뮬레이션학회논문지
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• 제12권1호
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• pp.21-34
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• 2003

This paper deals with a case study of workload analysis of an operator in an automatic line for machining the race of ball bearing. Eleven machines and three hoppers are installed in the line which is operated by an operator. The elements of operation are separated into machine controlled elements, operator controlled elements and machine/operator controlled elements. In order to analyze the system, time and motion studies are used for gathering input data for the simulation model. The first objective of this study is to evaluate whether the workload of operator is reasonable or not. The second objective is to increase throughput by reducing tact time and the last one is to increase frequencies of inspection by reducing interval. Thus we suggest some ideas for improvement, and as a result, the throughput is improved about 9%. In spite of the increasing of throughput, the allowance of operator is also increased about 4%.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1994년도 춘계학술대회 논문집
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• pp.59-62
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• 1994

Tact Electrical conductivity. optical absorption spectra of poly(p-phenylene vinylene) and their dependence on stretching are discussed in detail. The conductivity in the parallel direction to the stretching is higher over one order in magnitude than that in the perpendicular direction to the stretching is higher over one order in magnitude than that in the perpendicular direction to the stretching. The photocurrent spectrum for the ligh polarized parallel to the chain direction is much enhanced in lower photon energy compared with that for the light polarized perpendicular to that direction. The result may be originated in the difference of energies which is needed to photogenerate carriers wi th the light polarized parallel and perpendicular to the chain stretched direction.

• 로봇학회논문지
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• 제17권4호
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• pp.431-437
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• 2022

This paper deals with a study on the automatic depalletizing robot for parcels loaded in rolltainer of domestic postal distribution centers. Specifically, we proposed a robot system that detect parcels loaded in a rolltainer with a 3D camera and perform de-palletizing using a cooperative robot. In addition, we developed the task flow chart for parcel de-palletizing and the method of retreat motion generation in the case of collision with rolltainer. Then, we implemented the proposed methods to the robot's controller by developing robot program. The proposed robot system was installed at the Anyang Post Distribution Center and field tests were completed. Field tests have shown that the robotic system has a success rate of over 90% for depalletizing task. And it was confirmed that the average tact time per parcel was 7.3 seconds.

• Journal of information and communication convergence engineering
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• 제21권3호
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• pp.239-243
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• 2023

Owing to the environment in which it has become difficult to face people, on-tact communication has been activated, and online video conferencing platforms have become indispensable collaboration tools. Although costs have dropped and productivity has improved, communication remains poor. Recently, various companies, including existing online videoconferencing companies, have attempted to solve communication problems by establishing a videoconferencing platform within the virtual reality (Virtual Reality) space. Although the VR videoconference platform has only improved upon the benefits of existing video conferences, the problem of manually summarizing minutes because there is no function to summarize minute documents still remains. Therefore, this study proposes a method for establishing a meeting minute summary system without applying cases to a VR videoconference platform. This study aims to solve the problem of communication difficulties by combining VR, a metaverse technology, with an existing online video conferencing platform.

• 대한토목학회논문집
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• 제42권5호
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• pp.711-721
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• 2022

2019년 발생한 코로나라는 팬데믹 영향의 장기화로 인해 사람들 간 접촉을 하지 않고도 생활이 가능한 비대면 활동의 중요성이 증대되면서 우리사회는 본격적인 언택트(untact) 시대로 진입하게 되었다. 언택트 시대는 우리의 일상생활뿐만 아니라 산업사회를 디지털화로 재편하는 거대한 구조적 변화를 초래하는데 영향을 미쳤는데, 그 중심의 핵심기술에 디지털트윈(digital twin)이 있다고 해도 과언이 아니다. 디지털트윈은 4차 산업혁명에 접목되고 있는 다양한 기술력을 융합하여 현실세계를 가상의 디지털 세계에 그대로 재현해내는 기술로, 다양한 산업 공정 전반에 관여하여 산업 사회에서의 혁신을 선도하고 있다. 그러나 디지털트윈이 갖는 구조적 한계 및 환경적 제약으로 인해 동 기술은 모든 산업 제반에 걸쳐 적극적으로 활용되고 있지는 않다. 특히 건축 및 시설물 분야는 일상에서 건물의 주기적 관리가 요구되고 재난 발생 시 인명피해와도 직결되는 분야이기 때문에 디지털트윈의 접목 필요성이 더욱 제기되고 있는 분야지만 현실적으로 직면한 사항들이 디지털트윈의 적용에 있어 장애물로 작용하고 있다. 따라서 본 논문에서는 이러한 문제점에 착안하여 건축물 시설안전대응분야에서 디지털트윈 기술의 적용 필요성을 제시하고, 그로 인해 창출 가능한 기대효과를 기술함으로 디지털트윈의 적극적 활용을 강조한다. 더불어 디지털트윈이 현재 직면한 문제를 극복하고 향후 지속발전가능성이 높음을 시사하여 디지털트윈의 수요 창출을 견인하도록 연계짓는다.

• 조명전기설비학회논문지
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• 제23권1호
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• pp.69-77
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• 2009

최근, LCD(Liquid Crystal Display) 산업에서 클린룸의 규모가 커짐에 따라 물류 이송 시스템인 Stocker 시스템의 사이즈가 커지고 길이가 장거리화 되고 있다. 이에 제조 업체는 생산 수율을 높이기 위해 Stocker 시스템의 전체 택타임을 줄이기 위한 방안으로 차세대 Stocker 시스템의 속도를 증가하도록 요구되어 지고 있다. 따라서 본 논문은 차세대 Stocker 시스템의 속도 증가에 대한 비접촉 전원 시스템을 제안하고 Stocker 시스템을 부하로 선정하여 장거리 및 직선구간에 동작 가능한 비접촉 전원 시스템을 제작하여 부하의 여러 운전 패턴에 따른 비접촉 전원시스템의 실증시험, 입/출력 특성 및 효율을 분석하였다.

• International Journal of Computer Science & Network Security
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• 제22권12호
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• pp.63-70
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• 2022

The essence of the definition of "tolerance" is analyzed. Motivational, knowledge and behavioral criteria for tolerance of future teachers are highlighted. Indicators of the motivational criterion are the formation of value orientations, motivational orientation, and the development of empathy. Originality and productivity of thoughts and judgments, tact of dialogue, pedagogical ethics and tact are confirmed as indicators of the knowledge criterion. The behavioral criterion includes social activity as a life position, emotional and volitional endurance, and self-control of one's own position. The formation of tolerance is influenced by a number of factors: the social environment, the information society, existing stereotypes and ideas in society, the system of education and relationships between people, and the system of values. The main factors that contribute to the education of tolerance in future teachers are highlighted. Analyzing the structure of tolerance, it is necessary to distinguish the following functions of tolerance: - motivational (determines the composition and strength of motivation for social activity and behavior, promotes the development of life experience, because it allows the individual to accept other points of view and vision of the solution; - informational (understanding the situation, the personality of another person); - regulatory (tolerance has a close connection with the strong - willed qualities of a person: endurance, selfcontrol, self-regulation, which were formed in the process of Education); - adaptive (allows the individual to develop in the process of joint activity a positive, emotional, stable attitude to the activity itself, which the individual carries out, to the object and subject of joint relations). The implementation of pedagogical functions in the information society: educational, organizational, predictive, informational, communicative, controlling, etc. provides grounds to consider pedagogical tolerance as an integrative personal quality of a representative of any profession in the field of "person-person". The positions that should become conditions for the formation of tolerance of the future teacher in the information society are listed.