• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.11a
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• pp.246.1-246.1
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• 2004

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.3
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• pp.52-61
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• 2020

This study developed a legibility distance(LD) model for three colors used in VMS according to luminance under foggy conditions through experiments. For this, a simulated environment was created, and LD values of red, green, and yellow color were collected by increasing the luminance. From the test results, the LDs for red at luminance levels of 2,000 cd/㎡ and 20,000 cd/㎡ and a visibility distance of 10m were 10.2m and 18.8m, respectively, which was an improvement of 84%. The LD was improved by 34% and 17% at a visibility distance of 20 m and 30 m, respectively. For green, the LD was improved by 69%, 63%, and 19% at visibility distance of 10m, 20m, 30m, respectively. For yellow, the LD was improved by 100%, 47%, and 36% at visibility distance of 10m, 20m, 30m, respectively. The LD models for three colors were developed by using two independent variables, luminance value and visibility distance. The adjusted coefficients of the red, green, and yellow model equations were calculated as 0.982, 0.978, and 0.915, respectively, and the explanatory power of all models was very high.

• Journal of Korean Society of Transportation
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• v.25 no.5
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• pp.23-32
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• 2007

Variable message sign (VMS), which is used for providing real-time information on traffic conditions and incidents, is one of the important components of intelligent transportation systems. VMS messages need to meet the requirements with the consideration of human factors that messages should be readable and understandable while driving. This study developed a legibility distance model for VMS messages using in-vehicle differential global positioning data (DGPS). Traffic conditions, highway geometric conditions, and VMS message characteristics were investigated for establishing the legibility model based on multiple linear regression analysis. The height of VMS characters, speed, and the number of lanes were identified as dominant factors affecting the variation of legibility distances. It is expected that the proposed model would play a significant role in designing VMS messages for providing more effective real-time traffic information.

• Korean Journal of Heritage: History & Science
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• v.44 no.2
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• pp.58-75
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• 2011

This study aimed to demonstrate that photographic reading can be used to decipher epigraphs more effectively and accurately than conventional rubbing of epigraphy. When using the rubbing technique, the reading rate varies for the each epigraph depending on the time, person, and rubbing method. Thus, we compared the results of conventional rubbing to photographic reading focusing on unread and misread letters. According to the results, some letters were different from those in the reference books, and some letters that could have been readable via photographic reading were misread or read as different letters. In its undamaged state, the Pyeongwangtapbi Monument of Seonggak Daesa is supposed to contain a total of 2,049 letters, and 1,763 of them have been deciphered. This study corrected a total of 308 letters that had not been deciphered or deciphered inconsistently in existing literatures. However, it should be noted that the epigraphs of the Pyeongwangtapbi Monument of Seonggak Daesa read using the rubbing technique were made at least 30-100 years ago, and the photographic reading was performed in 2010. Thus, the overall condition is not perfectly identical. If we read and compare in the same condition, we may obtain even more reliable results. Therefore, based on this study of photographic reading, further studies regarding the correction of the contents of epigraphy should be performed.

• Journal of the Korean Society of Radiology
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• v.84 no.3
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• pp.653-662
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• 2023

Purpose This study aimed to determine the incremental value of using a structured report (SR) for US examinations of the pediatric appendix. Materials and Methods Between January 2009 and June 2016, 1150 pediatric patients with suspected appendicitis who underwent US examinations of the appendix were included retrospectively. In November 2012, we developed a five-point scale SR for appendix US examinations. The patients were divided into two groups according to the form of the US report: free-text or SR. The primary clinical outcomes were compared between the two groups, including the rate of CT imaging following US examinations, the negative appendectomy rate (NAR), and the appendiceal perforation rate (PR). Results In total, 550 patients were included in the free-text group and 600 patients in the SR group. The rate of additional CT examinations decreased by 5.3% in the SR group (8.2%, p = 0.003), and the NAR decreased by 8.4% in the SR group (7.8%, p = 0.028). There was no statistical difference in the appendiceal PR (37.6% vs. 48.0%, p = 0.078). Conclusion The use of an SR to evaluate US examinations for suspected pediatric appendicitis results in lower CT use and fewer negative appendectomies without an increase in appendiceal PR.

• Journal of Sensor Science and Technology
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• v.7 no.5
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• pp.342-349
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• 1998

A multipurpose TLD readout system for radiation dosimetry and thermoluminescence study is constructed and its characteristics are investigated. The thermoluminescent lights are measured by a PM tube and the current-to-frequency converter. TLDs are heated by platinum heater and the heating rate is linearly varied. Measurement of the glow curve and control of the whole system have been done by a personal computer equipped with an interface board. The automatic gain control can be done by the control software. The lower detection limit of the system is about $10\;{\mu}Gy$ and dose response is linear.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.4 no.2
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• pp.33-38
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• 1998

In point of flexographic printing on generally corrugated fiberboard cartons, the precision of film master and the adequate compression rate are very important factor in bar-code printing. Also, the complete system including scanner is essential for the purpose of enhancing the reading rate. The film master had good precision when the film was prepared by means of printing/developing machine after transformation of input bar-code number through transceiver, and the BWR 100 showed better compression rate than BWR 200. Also considering the bar-code reading, the complete system targeting the reading rate above 99.8% could be configured by Omni-Directional Scanner type accomplishing the reading rate above 99.5%.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.4
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• pp.455-461
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• 2010

It is one among very important works to detect change in urban area for effectively maintaining city. But, recently it is become more difficult to extract various changes using traditional method based on orthophotos because objects in urban area get higher and become more complex. To resolve these problems, we introduce new digital imagining system Pictometry which can acquire images of five directions (oblique and nadir). In this study, we compared the digital interpretation results based on Pictometry to the results from traditional method. As a result, Pictometry showed the good results in change detection of urban area.

• The Journal of the Acoustical Society of Korea
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• v.5 no.1
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• pp.35-40
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• 1986

본 연구는 펄스 반사법을 이용하여 금속 재료 단면의 영상을 얻는데 그 목적이 있다. 기존의 탐 상기는 대부분 A - 스캔 방식으로 결과를 전시하여 검사자가 직접 CRT 상에 나타난 결과를 판독해야 하므로 숙련자라 하더라도 어느정도 오차가 수반되며 판독에 시간이 요하는 등 불편이 따른다. 본 연구 에서는 판독 과정을 자동화함으로써 정확도와 검사 속도를 개선하였으며 탐촉 지점은 스텝핑모터를 이 용하여 일정 간격으로 제어하였다. 도 탐상 결과를 B-스캔 방식으로 영상 처리함으로써 재료 단면의 상 태 파악을 용이하게 하였다.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2007.04a
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• pp.191-196
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• 2007

본 연구에서는 변화탐지 기법을 통한 도심지 건축물의 판독가능성을 검토하기 위하여 항공사진 단영상 및 정사영상을 이용하여 영상정규화와 기하보정을 통한 image subtraction기법을 적용하여 변화 탐지를 실시하였다. 변화 탐지를 위한 임계값 설정에서 단영상 변화탐지는 임계값 90% 이상에서는 일정면적 이상의 변화지역이 뚜렷이 나타났으며 정사영상 변화탐지는 임계값 $70{\sim}80%$ 이상의 결과영상이 변화탐지에 적절한 것으로 나타났다. 단영상과 정사영상 변화탐지 결과를 필터링을 통해 일정면적 이하를 제거한 후 2002년 영상과 중첩하여 변화지역을 확인 하였다. 변화탐지 기법을 판독 작업에 활용한다면 판독 우선순위 결정에 많은 도움이 될 뿐만 아니라 영상의 종류와 필요에 따른 다양한 변화탐지 기법을 적용한다면 판독 작업에 많은 활용성을 기대할 수 있다.