• 한국정밀공학회지
• /
• 제10권3호
• /
• pp.191-197
• /
• 1993

In this paper, experimental studies are mainly carried out for the evaluation of precision cutting performance of a machine tool spincle running at high speed with the low load, in consideration of the bending vibration characteristics. As a result a process in presented for the practical application in the machine tools industry to evaluate the cutting performance in design stage of spindles.

• 한국BIM학회 논문집
• /
• 제7권1호
• /
• pp.18-27
• /
• 2017

Although Industry Foundation Classes (IFC) provide standards for exchanging Building Information Modeling (BIM) data, authoring tools still require manual mapping between BIM entities and IFC classes. This leads to errors and omissions, which results in corrupted data exchanges that are unreliable and thus compromise the validity of IFC. This research explored precedent work by Krijnen and Tamke, who suggested ways to automate the mapping of IFC classes using a machine learning technique, namely anomaly detection. The technique incorporates geometric features of individual components to find outliers among entities in identical IFC classes. This research primarily focused on applying this approach on two architectural BIM models and determining its feasibility as well as limitations. Results indicated that the approach, while effective, misclassified outliers when an IFC class had several dissimilar entities. Another issue was the lack of entities for some specific IFC classes that prohibited the anomaly detection from comparing differences. Future research to improve these issues include the addition of geometric features, using novelty detection and the inclusion of a probabilistic graph model, to improve classification accuracy.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 2000년도 제26회 펄프종이기술 국제세미나
• /
• pp.1-10
• /
• 2000

The development of paper machines, increasing machine speeds with new, mostly low basis weight and/or high ash content paper grades, as well as the fact that several trends regarding process items have increased the sensitivity of papermaking. At the same time, papermakers are looking for flexibility in the production line. We can say that with all PMs the biggest benefits with the lowest capital spending can be achieved by focusing on improved wet end management. In order to manage wet end chemistry on a paper machine, our goal is to control sub-process through which we can influence the operation of the entire wet end with maximum effect. Key measurements and controls are-white water consistency control which is the most effective way to control retention - charge demand measurement and control which takes care of concentration of the anionic material entering to PM -ash measurements and controls which are deeply related to retention and paper quality This paper presents and concentrates to two of these key controls ; retention and charge. The purpose of charge control is to give the process control the tools to react to changes caused by amount of dissolved and colloida material incoming to wet end system. It is called coagulation or fixing control. Retention control is then taking care of retention aid flow to the process by responding any changes seen in white water consistency. It is called flocculation control. Each of these solutions separately , and even more effectively all together, stabilize the wet end operations and so greatly improve the produced paper quality and machine runnability. Practical results will be presented and they are referring to the latest mill cases. We have developed the first wet end measuring system in the late 1980s and control solutions based on this modern measuring technology were completely updated in 1990s. This paper introduces the principle, operation , and results of our unique wet end analyzers (retention and charge ) which are at the level of automation solutions as a part of paper machine quality control Especially our newest member of the platform , on-line charge analyzer has reached and set new standards to the on-line charge monitoring.

• 펄프종이기술
• /
• 제32권5호
• /
• pp.44-53
• /
• 2000

The development of paper machines, increasing machine speeds with new, mostly low basis weight and/or high ash content paper grades, as well as the fact that several trends regarding process items have increased the sensitivity of papermaking. At the same time, papermakers are looking for flexibility in the production line. We can say that with all PMs, the biggest benefits with the lowest capital spending can be achieved by focusing on improved wet end management. In order to manage wet end chemistry on a paper machine, our goal is to control subprocesses through which we can influence the operation of the entire wet end with maximum effect. Key measurements and controls are - white water consistency control which is the most effective way to control retention. - charge demand measurement and control which takes care of concentration of the anionic material entering to PM. - ash measurements and controls which are deeply related to retention and paper quality. This paper presents and concentrates to two of these key controls: retention and charge. The purpose of charge control is to give the process control the tools to react to changes caused by amount of dissolved and colloidal material incoming to wet end system. It is called coagulation or fixing control. Retention control is then taking care of retention aid flow to the process by responding any changes seen in white water consistency. It is called flocculation control. Each of these solutions separately, and even more effectively all together, stabilize the wet end operations and so greatly improve the produced paper quality and machine runnability. Practical results will be presented and they are referring to the latest mill cases. We have developed the first wet end measuring system in the late 1980s and control solutions based on this modern measuring technology were completely updated in 1990s. This paper introduces the principle, operation, and results of our unique wet end analyzers (retention and charge) which are at the level of automation solutions as a part of paper machine quality control. Especially our newest member of the platform, on-line charge analyzer has reached and set new standards to the on-line charge monitoring.

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 2004년도 춘계학술대회 논문집
• /
• pp.466-471
• /
• 2004

In focused-ion-beam (FIB) application of micromachining and device transplantation, four kinds of FIB processes, namely FIB sputtering, FIB-induced etching, redeposition, and FIB-induced deposition, are well utilized. As with FIB systems, scanning electron microscopes(SEMs) were extensively used in the semiconductor industry. They are the tools of choice for defect review and providing the image resolution needed for process monitoring. The enhanced capabilities of a dual-column on one chamber system are quickly becoming realized by the nano industry for performing a wide range of application.

• 한국산업융합학회 논문집
• /
• 제3권1호
• /
• pp.83-90
• /
• 2000

The purpose of this study is the development of CAM system which can machine and measure any shape by CNC lathe. The overall goal of the CAM system is to achieve the CNC lathe machining, from roughing through to final measuring, The hardware of the system comprises PC, CNC lathe and measuring tools. There are three steps in the CNC lathe machining and measuring, (1) geometric modeling by the shape patterns, (2) NC commands generation by the tool path compensated for tool nose radius, (3) machining and workpiece measuring on the lathe. It is developed a software package, with which we can conduct a micro CAM system in the PC without economical burden.

• 디지털산업정보학회논문지
• /
• 제9권2호
• /
• pp.73-79
• /
• 2013

Cloud computing is a form which provides IT resources through network and pays the cost as much as you used. And it has advantages that it doesn't need to construct infrastructure and can be offered a variety of environments. The main core of these computing is virtualization technology. Security mechanism about attacks using vulnerabilities of virtualization technology isn't provided right and existing security tools can't be applied as it is. In this paper, we proposed honeyVM structure that can cope actively by collecting the information about attacks using virtualization vulnerability. Mamdani fuzzy inference is used to adjust dynamically the number of formed honeyVM depending on the load of system. Security structure to protect actual virtual machine from attacks and threats is proposed. The performance of the proposed structure in this paper measured occurred attack detection rate and resource utilization rate.

• 품질경영학회지
• /
• 제45권4호
• /
• pp.601-610
• /
• 2017

Purpose: Authors observe the digital twin enabled smart factory and/or digital manufacturing processes where Industry 4.0 technologies and quality management principles intersect. In this regard, this study reviews existing research regarding digital twins from the perspective of quality management. Methods: Initially, attention was given to how digital twins are manifested in the Industry 4.0 environment. Then, authors identify quality management elements amongst digital twin models, to align the concept of quality with the functional purpose of digital twins. After introducing specific examples of quality management tools applied to digital twins, the authors extend the domain of quality management into the analysis of multimedia format quality data obtained through machine vision. Results: Inspired by cases on the quality management application to digital twins, the authors suggest a framework for Industry 4.0 quality management. The envisioned suggested framework encompasses 4 dimensions, namely, 4M&1E, an application time window, new methodologies, and enabling technologies. Conclusion: Finally, the authors unfold the emerging trend of digital twin enabled smart factories, while emphasizing the necessity of quality management in conjunction with the introduction of digital twins.

• 한국기계가공학회지
• /
• 제16권5호
• /
• pp.31-39
• /
• 2017

Research in the machine tool industry has focused on ICT-based smart machines rather than hardware technologies related to machine tools. Real-time tool-status monitoring is representative of this type of technology and has become important for measuring sensors during cutting processes. In this paper, we studied several research areas and used a round bar to conduct fundamental research into the axial displacement of the main spindle of a tool when it was subjected to a machining load. We were able to use the gap sensor to detect the axial displacement indirectly by using grooves with various shapes on the round bar and sensing the gaps between the grooves. We then determined the optimal groove shape for monitoring the tool state.

• 기술혁신연구
• /
• 제24권2호
• /
• pp.21-56
• /
• 2016

그간 우리나라 등 후발주자의 추격과 그 성과에 대해 다양한 연구가 수행되었으나, 후발주자가 개발한 제품의 아키텍처가 추격 성과에 미친 영향에 대한 논의는 극히 부족하였다. 또한 공작기계의 움직임을 자동으로 제어하는 핵심 부품인 수치제어장치 분야에서 우리나라는 반도체, 조선, 자동차 산업과 달리 과거 40년에 가까운 기간 동안 다양한 개발체제 운영과 정부 지원에도 불구하고 제한적인 추격 성과를 보이거나 추격에 실패하였다. 이에 따라 본 연구에서는 우리나라 공작기계 수치제어장치 개발 사례를 중심으로 제품 아키텍처가 추격 성과에 미친 영향을 탐색적으로 고찰하였으며, 이를 위해 동 분야의 후발주자임에도 불구하고 세계 선도 기업으로 성장한 일본 화낙의 수치제어장치 아키텍처 진화 사례에 대한 심층 분석을 병행하였다. 연구결과 일본 화낙은 1980년대 중반 이후 수치제어장치 아키텍처의 개방형 모듈화를 달성함으로써 다양한 공작기계 생산 기업의 요구 사항에 부응하면서 대량 생산을 통한 원가 절감이 가능한 수치제어장치를 개발 생산하는 데 성공하였다. 이를 통해 화낙은 시장 점유율 확대 및 뛰어난 성과를 달성하였음을 발견하였다. 반면 우리나라는 1970년대 말 이후 약 40년 간의 추격 노력에도 불구하고 수치제어장치 아키텍처의 개방형 모듈화를 달성하지 못함으로 인해 다양한 수요 기업이 생산하는 공작기계에 채택되는데 실패하였으며, 결과적으로 제한된 추격 성과에 그치고 말았다. 또한 이러한 제한적인 추격 성과는 개발 주체의 파산과 매각, 폐쇄 등으로 이어지면서 기술적 지식의 누적에 큰 어려움을 겪었으며, 이로 인해 수치제어장치 아키텍처의 개방형 모듈화를 달성할 수 있는 만큼의 기술을 축적하거나 설계 역량을 확보하지 못했음을 발견하였다. 본 연구 결과는 제품 아키텍처 관점에서 후발주자의 추격 성과를 규명하고, 성공적인 기술 추격에도 불구하고 시장추격에 실패하는 원인을 규명할 수 있는 이론적 기반을 구축하는 데 그 의의가 있다.