• 한국기계가공학회지
• /
• 제13권4호
• /
• pp.113-120
• /
• 2014

To ventilate indoor spaces, axial single-blade fans are widely used in various areas, such as schools, houses, offices, and restaurants. Recently, axial single-blade fans were developed to realize energy efficiency and noise reduction improvements. Here, an experimental study of the air flow characteristics of an axial dual-blade fan is conducted. The characteristics of the axial dual-blade fan were tested via an air flow analysis and with prototypes. For the performance of the fan, the flow rate, power consumption, and noise were evaluated. The result showed that the axial dual-blade fan uses less power and produces less noise in comparison with an axial single-blade fan.

• 반도체디스플레이기술학회지
• /
• 제11권2호
• /
• pp.39-43
• /
• 2012

This paper presents a study on the design of a pulling module for silicon ingot and an apparatus of manufacturing silicon single crystal ingot using the same method. The pulling module is conceptually designed by using TRIZ. Czochralski method(CZ) is representative way to manufacture single crystal ingot for wafers. The seed can be broken by high tension which is caused by large weight of a silicon ingot. The solution of this problem has been derived using 6SC(6 steps creativity)TRIZ. The pulling module is actuated by DC motor and rollers. High tension in the seed is removed by the rotate-elevate motion of rollers in the pulling module. A rubber belt is included in the rotate-elevate mechanism for increasing friction between rollers and silicon ingot.

• Industrial Engineering and Management Systems
• /
• 제14권3호
• /
• pp.236-247
• /
• 2015

This study aims to examine the effects of industrial clustering and manufacturing flexibility on innovation capability and operational performance. This study follow a survey method to collect data pertaining to the phenomena of industrial clustering, manufacturing flexibility, innovation capability, and operational performance by utilizing a single respondent design. A total of 124 Indonesian manufacturing SMEs are taken to test the proposed theoretical model by utilizing covariance-based structural equations modeling approach. It was found that both industrial clustering and manufacturing flexibility was positively associated with operational performance and innovation capability as well. In addition, innovation capability may account for the effects of industrial clustering and manufacturing flexibility on operational performance. This implies that manufacturing SMEs have to reorient their production and operation perspectives, including agglomerate with other similar or related SMEs to develop and utilize their own resources. The SMEs also need to possess some degree of manufacturing flexibility in respond to the uncertain environment and market changes. In addition, the SMEs should put a greater emphasize to use industrial cluster and manufacturing flexibility benefits to generate innovation capability to achieve high performance.

• 한국경영과학회:학술대회논문집
• /
• 대한산업공학회/한국경영과학회 2004년도 춘계공동학술대회 논문집
• /
• pp.467-470
• /
• 2004

MANPro-based control is a novel control paradigm aimed at intelligent manufacturing systems on the basis of mobile agent-based negotiation process (MANPro). MANPro is a negotiation mechanism based on the agent-based control architecture and, especially, it adapts a mobile agent system called N-agent for the negotiation process. N-agent travels around the network of distributed manufacturing systems to acquire information, and it makes a decision for system control according to the obtained information. MANPro includes communication architecture and information architecture for intelligent shop floor control. MANPro also considers the following issues: (1) negotiation mechanism, (2) single-agent internal strategic policies, and (3) information model. Communication architecture concerns the first issue of the negotiation mechanism. It provides information exchanging mechanism with functional modules. In specific, N-agent is equipped with an intelligent reasoning engine with a built-in knowledge base. This reasoning engine is closely related to the single-agent internal strategic policies of the second issue. Finally, ontology-based information architecture addresses information models and provides a framework for information modeling on negotiation. In this paper, these three issues are addressed in detail and a framework of MANPro-based control is also proposed.

• 대한임베디드공학회논문지
• /
• 제18권6호
• /
• pp.303-310
• /
• 2023

A single vision system limits the ability to accurately understand the spatial constraints and interactions between robots and dynamic workers caused by gantry robots and collaborative robots during production manufacturing. In this paper, we propose a 3D pose registration method for dynamic workers based on a multi-domain vision system for safety monitoring in manufacturing environments. This method uses OpenPose, a deep learning-based posture estimation model, to estimate the worker's dynamic two-dimensional posture in real-time and reconstruct it into three-dimensional coordinates. The 3D coordinates of the reconstructed multi-domain vision system were aligned using the ICP algorithm and then registered to a single 3D coordinate system. The proposed method showed effective performance in a manufacturing process environment with an average registration error of 0.0664 m and an average frame rate of 14.597 per second.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
• /
• pp.193-198
• /
• 2002

In 1his paper, applicability of laser welding to joining process of single crystal nickel base superalloy turbine blades was investigated. Because heat input of laser welding is more precisely controlled 1han TIG welding, it is possible to optimize solidification microstructure of the welds. Since in single crystal nickel base superalloy the crystal orientation have a significant effect on the strength, it is important to control the solidification microstructure in the fusion zone. A single crystal nickel base supera1loy, CMSX-4, plates were bead-on welded and butt welded using a $CO_2$ laser. The effects of microstructure and crystal orientation on properties of the weld joints were investigated. In bead-on weldling, welding directions were deviated from the base metal [100] direction by 0, 5, 15 and 30 degrees. The welds with deviation angles of 15 and 30 degrees showed fusion zone transverse cracks. As the deviation angles became larger, the fusion zone had more cracking. In the cross section microstructure, the fusion zone grains in 0 and 5 degrees welds grew epitaxially from the base metal spins except for the bead neck regions. The grains in the bead neck regions contained stray crystals. As deviation angles increased, number of the stray crystals increased. In butt welding, the declinations of the crystal orientation of the two base metals varied 0, 5 and 10 degrees. All beads had no cracks. In the 5 degrees bead, the cross section and surface microstructures showed that the fusion zone grains grew epitaxially from the base metal grains. However, the 10 degrees bead, the bead cross section and surface contained the stray crystals in the center of the welds. Orientations of the stray crystals accorded with the heat flow directions in the weld pool. When the welding direction was deviated from the base metal [100] direction, cracks appeared in the area including the stray crystals. The cracks developed along the grain boundaries of the stray crystals with high angles in the final solidification regions at the center of the welds. The fracture surfaces were covered with liquid film. The cracks, therefore, found to be solidification cracks due to the presence of low melting eutectic. As the results, in both bead-on welding and butt welding the deviation angles should be control within 5 degrees for preventing the fusion zone cracks. To investigate the mechanical properties of the weld joints, high temperature tensile tests for bead-on welds with deviation angles of 0 and 5 degrees and the butt welds with dec1ination angles of 0, 5 and 10 degrees were conducted at 1123K. The the tensile strength of all weld joints were more 1han 800MPa that is almost 80% of the tensile strength of the base metal. The strength of the laser weld joints were more than twice that of tue TIG weld joints with a filler metal of Inconel 625. The results reveals 1hat laser welding is more effective joining process for single crystal nickelbase superalloy turbine blades 1han TIG welding.

• Design & Manufacturing
• /
• 제15권1호
• /
• pp.48-56
• /
• 2021

The quality of products produced by injection molding process is greatly influenced by the process variables set on the injection molding machine during manufacturing. It is very difficult to predict the quality of injection molded product considering the stochastic nature of manufacturing process, because the process variables complexly affect the quality of the injection molded product. In the present study we predicted the quality of injection molded product using Artificial Neural Network (ANN) method specifically from Multiple Input Single Output (MISO) and Multiple Input Multiple Output (MIMO) perspectives. In order to train the ANN model a systematic plan was prepared based on a combination of orthogonal sampling and random sampling methods to represent various and robust patterns with small number of experiments. According to the plan the injection molding experiments were conducted to generate data that was separated into training, validation and test data groups to optimize the parameters of the ANN model and evaluate predicting performance of 4 structures (MISO1-2, MIMO1-2). Based on the predicting performance test, it was confirmed that as the number of output variables were decreased, the predicting performance was improved. The results indicated that it is effective to use single output model when we need to predict the quality of injection molded product with high accuracy.

• 한국생산제조학회지
• /
• 제19권4호
• /
• pp.469-475
• /
• 2010

The objective of this study is to integrate reliability analysis into shape optimization problem using the evolutionary structural optimization (ESO) in the application example. Reliability-based shape optimization is formulated as volume minimization problem with probabilistic stress constraint under minimization max. von Mises stress and allow stress. Young's modulus, external load and thickness are considered as uncertain variables. In order to compute reliability index, four methods, i.e., reliability index approach (RIA), performance measure approach (PMA), single-loop singlevector (SLSV) and adaptive-loop (ADL), are used. Reliability-based shape optimization design process is conducted to obtain optimal shape satisfying max. von Mises stress and reliability index constraints with the above four methods, and then each result is compared with respect to numerical stability and computing time.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
• /
• pp.240-241
• /
• 2007

In general, high temperature superconducting coated conductors have intermediary buffers layer consisting of seed, diffusion barrier and cap layers. Simplification of the oxide materials buffer architecture in the fabrication of high temperature superconducting coated conductors is required because the deposition of multi-layers buffer architecture leads to a longer manufacturing time and a higher cost process of coated conductors. Thus, single buffer layer deposition seems to be important for practical coated conductor manufacturing process. In this study, a single gradient layered buffer deposition process of YZO for low cost coated conductors has been tried using DC reactive sputtering technique. About several thick YZO gradient single buffer layers deposited by DC co-sputtering process were found to act as a diffusion layer.

• 정보처리학회 논문지
• /
• 제13권2호
• /
• pp.26-33
• /
• 2024

최근에 들어 디지털 트윈 기술에 대한 관심이 급증하고 있다. 디지털 트윈은 컴퓨터 기반 시뮬레이션을 통해 물리적 현상이나 사물을 모사함으로써 대상을 최적화하는 기술이다. 현재는 특정 분야에 국한되는 프로세스를 최적화하기 위한 단일 디지털 트윈이 개발되고 있지만, 독립된 디지털 트윈만으로는 현실의 방대하고 복합적인 프로세스를 분석하기 어렵다. 이를 극복하고자 도입된 개념이 연합 디지털 트윈이다. 지금까지 연합 디지털 트윈의 연구 방향은 주로 도시와 같이 거시적인 대상을 최적화하는 방식에 중점을 두었다. 그러나 트윈이 상호 연계된다는 특성을 활용하면 기존에 구현되었던 단일 디지털 트윈의 모듈화도 가능할 것으로 보인다. 본 연구에서는 프로세스 최적화와 관련된 기능상의 관점에서 단일 디지털 트윈과 연합 디지털 트윈의 개념 및 상호 관계를 정립하고, 이를 토대로 연합 디지털 트윈을 활용한 단일 디지털 트윈의 모듈화 기법을 설계한다. 아울러, 실제 면 제조 공정 사례를 바탕으로 모듈화 기법을 적용한 모델을 설계함으로써 제안하는 방법론의 효용성을 논의하고자 한다.