• Title/Summary/Keyword: 프로빙 정확도

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Touch-Trigger Probe Error Compensation in a Machining Center (공작기계용 접촉식 측정 프로브의 프로빙 오차 보상에 관한 연구)

  • Lee, Chan-Ho;Lee, Eung-Suk
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.35 no.6
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    • pp.661-667
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    • 2011
  • Kinematic contact trigger probes are widely used for feature inspection and measurement on coordinate measurement machines (CMMs) and computer numerically controlled (CNC) machine tools. Recently, the probing accuracy has become one of the most important factors in the improvement of product quality, as the accuracy of such machining centers and measuring machines is increasing. Although high-accuracy probes using strain gauge can achieve this requirement, in this paper we study the universal economic kinematic contact probe to prove its probing mechanism and errors, and to try to make the best use of its performance. Stylus-ball-radius and center-alignment errors are proved, and the probing error mechanism on the 3D measuring coordinate is analyzed using numerical expressions. Macro algorithms are developed for the compensation of these errors, and actual tests and verifications are performed with a kinematic contact trigger probe and reference sphere on a CNC machine tool.

Delayed packet-pair scheme for passive network capacity estimation with TCP (TCP의 수동적 네트워크 용량 측정을 위한 지연 패킷 페어 기법)

  • Hwang, Jae-Hyun;Yoo, See-Hwan;Yoo, Hyuck
    • Proceedings of the Korean Information Science Society Conference
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    • 2008.06d
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    • pp.272-275
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    • 2008
  • 종단에서 네트워크 용량에 대한 정보는 사용자뿐 아니라 전송 계층 프로토콜 상에서 전송량 등을 조절하기 위한 중요한 용도로 활용된다. 이러한 네트워크 용량(또는 대역폭)을 종단에서 측정하기 위해 활용되는 방법 중 하나가 바로 패킷 페어 기법이다. 패킷 페어 기법은 계산이 간단하고 빠른 측정이 가능하다는 장점이 있으나, 각 프로빙 패킷에 대한 즉각적인 응답 패킷을 필요로 하기 때문에 지연 ACK 방식이 존재하는 TCP 상에서는 적용하기 어렵다는 단점이 있다. 본 논문에서는 이러한 지연 ACK의 효과를 그대로 유지하면서 네트워크 용량의 추정이 가능한 지연 패킷 페어 기법을 제안한다. 시뮬레이션 결과를 통해 제안된 지연 패킷 페어 기법이 기존 방식의 정확성, 빠른 측정 시간 등의 장점을 보존하면서 지연 ACK의 사용 여부에 관계없이 정확히 동작할 수 있음을 보였다.

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Traffic Information Service System Using Gateway between VANET and Infrastructure Network (VANET과 기간통신망간 게이트웨이를 사용한 교통정보 서비스 시스템)

  • Park, Mi-Ryong;Kim, Sang-Ha;Kim, Dongwon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.5
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    • pp.61-66
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    • 2012
  • We propose a traffic information service system for which traffic data are transmitted over vehicle ad-hoc network from neighbor vehicles, and eventually provided to the traffic information center through a few gateway vehicles which are capable of inter-working with the infrastructure network like 3G. The center broadcasts the traffic information through the FM radio. The proposed scheme allows collecting and analyzing traffic status of large areas without incorporating separated monitoring systems, e.g., probe cars and enables to provide accurate traffic information to drivers in timely manner. We also evaluate its performance by ns-3 simulation.

A Fast Sensing Method using Concurrent Driving and Sequential Sensing for Large Capacitance Touch Screens (동시구동 및 순차센싱을 이용한 대형 정전용량 터치스크린용 고속 센싱 기법)

  • Mohamed, Mohamed G.A.;Kim, HyungWon;Cho, Tae-Won
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.4
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    • pp.62-70
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    • 2015
  • Recently the demand for projected capacitance touch screens is sharply growing especially for large screens for medical devices, PC monitors and TVs. Large touch screens in general need a controller of higher complexity. They usually have a larger number of driving and sensing lines, and hence it takes longer to scan one frame for touch detection leading to a low frame scan rate. In this paper, a novel touch screen control technique is presented, which scans each frame in two steps of simultaneous multi-channel driving. The first step is to drive all driving lines simultaneously and determine which sensing lines have any touch. The second step is to sequentially rescan only the touched sensing lines, and determine exact positions of the touches. This technique can substantially increase the frame scan rate. This technique has been implemented using an FPGA and an AFE board, and tested using a commercial 23-inch touch screen panel. Experimental results show that the proposed technique improves the frame scan rate by 8.4 times for the 23-inch touch screen panel over conventional methods.

Suggestion of a Digital Curation Framework for Historical Contents (역사콘텐츠 활용을 위한 디지털 큐레이션 프레임워크 제안)

  • Lee, Hyewon
    • Journal of Korean Society of Archives and Records Management
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    • v.16 no.3
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    • pp.235-256
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    • 2016
  • This study suggested a digital curation framework for supporting the digital policy of institutes that collect memory. As such, it conducted a literature review and an analysis of digital curation models, as well as a focus-group interview of historians and graduate students majoring in historical studies. In this study, digital curation framework refers to an abstract model for supporting policy development and the planning for a high-level view of the archival information service. This implications of this framework are as follows: (1) to emphasize the data life cycle and connection between stages and actions; (2) to make an infra-schema for understanding institutes that create, arrange, or store specific data as the same history contents have to be provided by different institutes and as there are differences in the data's value; (3) to check the present conditions of information services and their systems; (4) to consider the practical applications of contents that have been collected and stored; and (5) to converge all data in one system through the framework and activate diverse works in the context of the framework.

Development of Meta-Model Using Process Model Data for Predicting the Water Quality of Nakdong River (낙동강 수질 예측을 위한 프로세스 모델링 자료를 이용한 메타모델 개발)

  • Yu, Myungsu;Song, Young-Il;Seo, Dongil
    • Proceedings of the Korea Water Resources Association Conference
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    • 2020.06a
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    • pp.91-91
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    • 2020
  • IPCC (Intergovernmental Panel on Climate Change) 5차 평가보고서에 의하면 최근 배출 온실가스의 양은 관측 이래 최고 수준이며 온실가스로 인한 기후변화는 인간계와 자연계에 광범위한 영향을 주고 있다고 보고하였다. 기후변화의 영향은 국제적으로 빙하 감소, 사막화, 해수면 상승 등 뚜렷하게 나타나고 있다. 이러한 기후변화에 대응하기 위해 온실가스 완화 정책과 동시에 새로운 기후변화 환경에 적응하는 것이 필요하다. 기후변화 적응이란 현재 나타나고 있거나 미래에 나타날 것으로 예상되는 기후변화의 파급효과와 영향에 대응할 수 있도록 하는 모든 행동이며 이를 위해서는 기후변화 영향분석이 수반되어야 한다. MOTIVE 연구단에서는 기후변화 적응대책 수립의 지원을 목표로 7개 부문(건강, 물관리, 농업, 산림, 생태, 해양, 수산)에서 "한국형 통합평가 모형"을 개발하고 있다. 각 부문에서 개발하는 프로세스 모델은 시스템에 대한 지식을 가진 상황에서 사용하면 신뢰할 수 있는 예측 결과를 얻을 수 있지만, 부문별 통합을 통한 영향 분석 시 타 분야에 대한 지식이 수반되어야 하는 어려움을 가진다. 이를 위해 본 연구에서는 시스템 내의 물리적 프로세스에 대한 요구 없이 입출력 데이터만을 이용하여 결과를 신속하게 추정하는 데이터 모델링(기계학습)을 이용하였다. 데이터 모델링을 위한 데이터는 다양한 자연 현상에 대한 BANPOL(수질 프로세스 모델) 분석을 통한 자료를 이용하여 학습 자료를 구축하였다. 즉, 데이터 모델링은 BANPOL 모델을 대리하는 메타모델이며, 낙동강 표준유역에 대한 유량 및 수질을 높은 상관성으로 추정하였다. 원 모델보다 정확도는 낮을 수 있으나 메타모델의 개발을 통한 웹 시스템을 개발하여 비전문가의 구동 및 신속한 기후 시나리오를 적용할 수 있는 환경을 개발하였다.

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Children′s Attitudes Toward Food Advertisement on Children′s Television Program (어린이 시간대 식품광고에 대한 어린이들의 수용 태도)

  • 김경희;강금지
    • Korean journal of food and cookery science
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    • v.13 no.5
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    • pp.648-660
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    • 1997
  • The study was conducted to investigate children's attitudes toward food advertisement on children's television programs. A total of 868 subjects were selected from two KangNam and KangBook elementary schools (4, 5, 6th graders). First, it was reviewed food ads. On children's television program on 3 channels between 5∼7 pm from April to July in 1997. Among the total television commercials, 58% were food product ads.. Among the advertised food, the largest number of ads. was for beverages (21.6%) and the next was for cookies (19.7%), followes by sharbet and ice cream (19.5%), fast food (12.4%), cereal (5.5%) and milk and milk products (2.9%). This review revealed that the mostly advertised food are high in calorie, fat and sugar. Secondly, it was conducted a survey. The results of the survey were as follows: weekly average TV watching hours per child: 13.5. 50.8% of the children watched children's program on TV. 83.9% of the subjcts answered that they get their information about new food through TV ads.. 59.2% of children tried to buy the food advertised on TV program. The relationship between TV food ads. and health, 49.4% of the children answered that advertised food were not good for one's health. When we asked them to choose between advertised and non-advertised food, they preferred the advertised ones, such as cookies, beverages, fast food restaurants and cereals (p<0.001). The results of this study suggest that children's purchasing and selecting of food were influenced by TV food advertisement. Therefore, education is needed which will help children's make responsible, informed consumers choices.

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Analysis of Purchasing Behaviors of Processed Foods in High School Students in Yongin Region (용인지역 고등학생의 가공식품 구매행동 분석)

  • Koo, Hee Jin;Kim, Seong Yeong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.12
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    • pp.1929-1936
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    • 2014
  • This study investigated purchasing behaviors of processed foods in high school students (male 94 and female 85) in the Yongin region. Frequency of eating processed foods was generally once (36.9%) or twice (32.4%) a day. Frequency according to processed food items was in the following order: confectionary (31.3%)> beverages (17.3%)> breads (12.3%)> instant noodles (11.7%) and milk or dairy products (11.7%)> frozen desserts (10.6%). The places for purchasing were a big mart (30.7%), convenience store (28.5%), and school cafeteria (26.8%). The reasons for purchasing were 'tasty' at 43.6% and 'hungry' at 35.2%. Main factors affecting purchasing were 'taste' at 70.9%, followed by price (16.2%)> quantity (5.6%)> nutrition (4.5%). The most important parts of food and nutrition labels were 'shelf-life' (67.0%) and 'calories' (57.5%). Degrees of confirmation of food and nutrition labeling were 'always' (12.3%), 'rarely' (28.5%), and 'sometimes' (59.2%). The reasons for not reading labels were 'unconcerned' (27.9%), 'too tiny lettering' (28.5%), 'hard to understand' (16.2%), and 'habitually' (15.1%). These results reflect low attention of high school students towards healthy food choices using food and nutrition labeling during purchasing. In conclusion, a specific education program for providing accurate product information as well as leading healthy purchasing behaviors should be required.