• 한국정밀공학회지
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• 제29권2호
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• pp.139-146
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• 2012

A multi-tasking machine tool for large scale marine engine crankshafts has been developed together with design technologies for its special devices. Since work pieces, that is, crankshafts to be machined are big and heavy; weight of over 100 tons, length of 10 m long, and diameter of over 3.5 m, several special purpose core devices are necessarily developed such as PTD (Pin Turning Device) for machining eccentric pin parts, face place and steady rest for chucking and resting heavy work pieces. PTD is a unique special purpose device of open-and-close ring typed structure equipped with revolving ring spindle for machining eccentric pins apart from journal. In order to achieve high rigidity of the machine tool, structural design optimization using TMSA (Taguch Method based Sequential Algorithm) has been completed with FEM structural analysis, and a hydrostatic bearing system for the PTD has been developed with theoretical hydrostatic analysis.

• Journal of Mechanical Science and Technology
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• 제18권5호
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• pp.770-779
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• 2004

This paper describes the micro cutting of wear resistant tungsten carbides using PCD (Poly-Crystalline Diamond) cutting tools in performance with SEM (Scanning Electron Microscope) direct observation method. Turning experiments were also carried out on this alloy (V50) using a PCD cutting tool. One of the purposes of this study is to describe clearly the cutting mechanism of tungsten carbides and the behavior of WC particles in the deformation zone in orthogonal micro cutting. Other purposes are to achieve a systematic understanding of machining characteristics and the effects of machining parameters on cutting force, machined surface and tool wear rates by the outer turning of this alloy carried out using the PCD cutting tool during these various cutting conditions. A summary of the results are as follows: (1) From the SEM direct observation in cutting the tungsten carbide, WC particles are broken and come into contact with the tool edge directly. This causes tool wear in which portions scrape the tool in a strong manner. (2) There are two chip formation types. One is where the shear angle is comparatively small and the crack of the shear plane becomes wide. The other is a type where the shear angle is above 45 degrees and the crack of the shear plane does not widen. These differences are caused by the stress condition which gives rise to the friction at the shear plane. (3) The thrust cutting forces tend to increase more rapidly than the principal forces, as the depth of cut and the cutting speed are increased preferably in the orthogonal micro cutting. (4) The tool wear on the flank face was larger than that on the rake face in the orthogonal micro cutting. (5) Three components of cutting force in the conventional turning experiments were different in balance from ordinary cutting such as the cutting of steel or cast iron. Those expressed a large value of thrust force, principal force, and feed force. (6) From the viewpoint of high efficient cutting found within this research, a proper cutting speed was 15 m/min and a proper feed rate was 0.1 mm/rev. In this case, it was found that the tool life of a PCD tool was limited to a distance of approximately 230 m. (7) When the depth of cut was 0.1 mm, there was no influence of the feed rate on the feed force. The feed force tended to decrease, as the cutting distance was long, because the tool was worn and the tool edge retreated. (8) The main tool wear of a PCD tool in this research was due to the flank wear within the maximum value of $V_{max}$ being about 260 $\mu\textrm{m}$.

• 대한간호학회지
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• 제25권2호
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• pp.295-315
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• 1995

This qualitative nursing research used a hermeneutic phenomenological approach to discover meaning in mid - aged women's experience of mastectomy. The ultimate aim of the inquiry was to discover the essence of mid-aged women's experience and promote understanding. The study was guided by Van Manen's method for doing research. The method of inquiry included. turning to phenomenon of interest ; inquiring and investigating experience as it was lived rather than as conceptualized ; reflecting and analyzing essential themes which characterize phenomenon : and describing phenomenon through art of writing and rewriting. Multiple strategies for data collecting were needed : in depth face-to-face interview ; analysis of women's writings ; artistic works : and analysis of examples of phenomenon in art, litera lure, and drama. Although the experience was different for all of the women interviewd, essential themes of experience emerged : Self-discovering of vicious disease, Divining punishment-unfortunate women, loss of self though the scar, a night-mare, change of life values and attitudes, rediscovering living alone, living through with fearing of death. Findings from artistic and creative inquiry further validated findings and meaning descovered. The study illuminated meaning and simultaneously validated the phenomenological research process. Essential themes for understanding women's experience, implications for education, research, and practice, direction and need for continuing inquiry were identified.

• 대한기계학회논문집
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• 제12권4호
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• pp.694-704
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• 1988

본 연구에서는 현장에서 흔히 수행되는 가공 후(post-process) 측정만을 이용 한 단일절삭(single-pass)으로써 공작물이 원하는 일정한 직경을 유지할 수 있다는 것 을 실험을 통해 검증해 보이고자 한다. 이와 같은 방식은 이미 보오링 작업 중 보오 링바의 노출 길이 변화에 따른 가공면의 내경 오차를 없애주기 위한 방법으로써 제시 된 바 있다. 즉 반복 최소 자승법(recursive least squares)으로 미리 가정된 절삭 조건과 공작물 처짐 사이의 관계식과 관련된 계수를 가공 후에 가공 공작물의 표면 측 정으로 매 번보정(update)시켜 줌으로써 일정 직경을 얻기위한 절삭조건을 결정하고자 한다.

• 한국농촌생활과학회지
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• 제8권2호
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• pp.93-110
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• 1997

The customs of women s riding horse was prevalent in thriving period. The face toilet was mainly used by Gau Chang pattern. Wha Jun (chinen; Hwa-Qun(화전), make-up on forehead), was influenced nearly by Gua Chang and distantly by India. Penciling eyebrows with blue was transmitted from persia. Chinese cosmetics was most influenced during Tang Dynasty for it's colorful make-up and facial decorations such as Aek-Whang(액황), Wha-Jung(화전), Jang-Yob(장엽), Swa-Hong(사홍) and those made many Dynasty, since those kinds of styles were the result of mixture between traditional chinese and western styles, it became so unique and diverse. The Declining period of the Tang Dynasty has begun from the turning point, resulting from Rebellion of An Ru Sha'. Rebellion of An Ru Sha' made the chinese people have a sense of precaution, and an antipathy against babarian. Furthermore, the power of Tang Dynasty onto the countries bordering on western china unfortunately was declining due to the defeat at 99 the Talas war in 751. As the fashion of ‘Ho’ disappeared the costume pattern was restored to the traditional Chinese style of large sleeve and broad width. However, the Tibetan mode was appeared in women's hair style and face toilet since Yuan Ha (801-812). In Song Dynasty, women's make-up and adorment were originated from Dang Dynasty, but those were more simple than in Dang Dynasty.

• International Journal of Knowledge Content Development & Technology
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• 제6권2호
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• pp.29-42
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• 2016

Performing an online health search is a popular activity conducted on the Internet. Research studies from developed countries provide information on source used, type of search performed and devices used to perform the search. However, the same cannot be said about the online health information searching scene in South East Asia. Online health information searching is gaining popularity in South East Asia. Citizens in these countries are turning to the Internet to obtain health information quickly. Current research studies pertaining to online health information searching in South East Asian is limited, particularly relating to search experiences of South East Asian health searchers. Search experience is pertinent as it could deter or encourage the possibility of conducting future health searches. In this research study, a user study was conducted to describe the online search experience of South East Asian health searchers. A face to face interview with 50 participants was conducted. The interview was audio recorded and transcribed verbatim. Results indicate participants have positive and negative search experiences. In some cases, post search outcomes influenced the search experience. Results of this research study contribute to the growing domain of knowledge in relation to online health information searching. Results of this study also provide an understanding pertaining to the search experience of South East Asian online health searchers.

• 한국정밀공학회지
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• 제15권4호
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• pp.36-43
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• 1998

We experimented turning SCM440, called difficult-to-cut materials in general, using tungsten carbon tool(PIO) in order to elevate machinability by a new cutting method. The cutting tool designed and made to study was cooled to -17$0^{\circ}C$ in about 1 minute by liquid nitrogen. Then, we operated cryogenic cutting by cooling tool with liquid nitrogen and stuided the effect about cutting force, chip thickness, surface roughness, behavior of tool wear and cutting temperature. In addition, we investigated the possibility that sur face roughness of workpiece can be predicted analyzing cutting characteristics.

• 제어로봇시스템학회논문지
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• 제13권9호
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• pp.825-831
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• 2007

In this paper, an interface between a human and a computer is presented. The human and computer interface(HCI) serves as another area of human and machine interfaces. Methods for the HCI we used are voice recognition and image recognition for detecting human's emotional feelings. The idea is that the computer can recognize the present emotional state of the human operator, and amuses him/her in various ways such as turning on musics, searching webs, and talking. For the image recognition process, the human face is captured, and eye and mouth are selected from the facial image for recognition. To train images of the mouth, we use the Hopfield Net. The results show 88%$\sim$92% recognition of the emotion. For the vocal recognition, neural network shows 80%$\sim$98% recognition of voice.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.809-813
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• 2000

In this study, screw machining system by use of a rotational tool such as an end-mill or a face cutter with Y axis off-set on a CNC turing center was developed for quick machining. In this system, It was possible to use different tools for different processes, and by off-setting the tool in Y direction by calculated amount it was possible to avoid tool interference problem which could occur within the central area at the end of a tool. In addition, machining a screw with a helix of up to 3 different leads combined and with tapered minor diameter was possible.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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• pp.251-256
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• 1999

"Ploughing" on the flank face of the tool in the metal cutting process is due to the tool in the metal cutting process is due to the finite edge radius of the tool and due to the development of flank wear. Because of the high stresses near the cutting edge, elastic-plastic deformation would be caused between the tool and the machined surface over a small area of the tool flank. The deformation would affect the roughness of the machined surface. Recently, some attempts have been made to predict the surface roughness, but elastic-plastic effect due to ploughing in the cutting process has not been considered. The research has analyzed mechanism of the ploughing of the cutting process using contact mechanics. Tool and workpiece material properties have been taken into account in the prediction of the surface roughness. The surface roughness has been simulated by the surface-shaping system. The results between experiment and simulation have been compared and analyzed. analyzed.