• Proceedings of the KSRS Conference
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• 1999.11a
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• pp.214-218
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• 1999

The aim of our study is to develop new algorism for sea fog detection by using Geostational Meteorological Satellite-5(GMS-5) and suggest the techniques of its continuous detection. So as to detect daytime sea fog/stratus(00UTC, May 10, 1999), visible accumulated histogram method and surface albedo method are used. The characteristic value during daytime showed A(min) > 20％ and DA < 10％ when visble accumulated histogram method was applied. And the sea fog region which detected is of similarity in composite image and surface albedo method. In case of nighttime sea fog(18UTC, May 10, 1999), infrared accumulated histogram method and maximum brightness temperature method are used, respectively. Maximum brightness temperature method(T_max method) detected sea fog better than IR accumulated histogram method. In case of T_max method, when infrared value is larger than T_max, fog is detected, where T_max is an unique value, maximum infrared value in each pixel during one month. Then T_max is beneath 700hpa temperature of GDAPS(Global Data Assimilation and Prediction System). Sea fog region which detected by T_max method was similar to the result of National Oceanic and Atmosheric Administration/Advanced Very High Resolution Radiometer (NOAA/AVHRR) DCD(Dual Channel Difference). But inland visibility and relative humidity didn't always agreed well.

• Journal of Information Science Theory and Practice
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• v.11 no.4
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• pp.40-50
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• 2023

Research in interdisciplinary fields like biomechanics is published in a variety of journals whose visibility depends on bibliometric indexing that is often driven by citation analysis of bibliometric databases. This study documented variation in publication metrics and research subject categories assigned to 14 biomechanics journals. Authors, citation, and citation rate (CR) were collected for the top 15 cited articles in the journals retrieved from the Google Scholar service. Research subject categories were also extracted for journals from three databases (Dimensions, Journal Citation Reports, and Scopus). Despite the focus on biomechanics for the journals studied, these biomechanics journals have widely varying CR and subject categories assigned to them. There were significant (p=0.001) and meaningful (77-108%) differences in median CR between average, low, and high CR groups of these biomechanics journals. Since CR are primary data used to calculate most journal metrics and there is no one biomechanics subject category, field normalization for journal citation metrics in biomechanics is difficult. Care must be taken to accurately interpret most citation metrics of biomechanics journals as biased proxies of general usage of research, given a specific database, time frame, and area of biomechanics research.

• ETRI Journal
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• v.36 no.2
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• pp.188-196
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• 2014

This paper describes a simple delay diversity technique for terrestrial digital multimedia broadcasting (T-DMB) and digital audio broadcasting in a single-frequency network (SFN). For the diversity technique, a delay diversity scheme is adopted. In the delay diversity scheme, a non-delayed signal is transmitted in the first antenna, and delayed versions of the signal are transmitted in each additional antenna. For an SFN environment with multiple transmitters, delay diversity can be executed by controlling the emission times of the transmitters. This SFN delay diversity scheme does not require any hardware changes in either the transmitter or receiver, and perfect backward compatibility can be acquired. To evaluate the performance improvement, laboratory tests are executed with various types of commercial T-DMB receivers as well as a measurement receiver. The improvement in the bit error rate performance is evaluated using a measurement receiver, and an improvement of the threshold of visibility value is evaluated for commercial receivers. Test results show that the T-DMB system can obtain diversity gain using the described technique.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1353-1354
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• 2015

본 연구에서는 관측자료 기반의 안개 예보를 수행하기 위해 특징선택을 이용한 SVR 회귀분석 기반 시정 예측 가이던스를 개발하였다. 예측에 필요인자를 사전에 선택하는 유전알고리즘 기반의 최적화 방법을 적용하여, 관측된 여러 기상인자의 입력인자 중 실제 시정을 예측하기 위한 입력인자를 선택하여 준다. 지점별 안개발생에 필요한 입력인자 및 예측 모델을 구성하여 통합적인 예측 모델이 아닌 각 지점에 최적화된 정보를 제공할 수 있도록 예측을 수행한다. 자료의 수집 특성상 3시간 간격으로 3시간 예보를 위한 시정을 예측하고, 예측 모델의 검증을 위해 현업의 수치모델 기반의 시정예측 정보와의 비교를 통해 실제 안개 시점에 대해 비교 분석하였고 그 결과를 통해 긍정적인 효과를 보였다. 예측모델을 적용하여 지도에 예측시정 정보를 제공하는 표출 시스템을 통해 실시간 가이던스를 제공하고자 연구를 수행하였다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2004.11a
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• pp.281-284
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• 2004

This paper described an Enhanced-xVSB system for improving mobile/pedestrian reception performance to the ATSC DTV 8-VSB transmission standard. E-xVSB system can transmit a mixture of normal (8-VSB) stream and enhanced (robust) stream. The robust stream has a higher threshold of visibility (TOV) compared to the standard stream, and legacy receivers ignore the robust packets. Thus, Enhanced-xVSB system is fully backward compatible with a current ATSC standard. for mobile and portable reception support, E-xVSB system adopts a reduced constellation method as well as enhanced trellis-coded modulation scheme. E-xVSB system supports a variety of enhanced modulation schemes: Pseudo-2VSB, Enhanced-4VSB, modified Enhanced-8VSB and Hybrid-VSB. Proposed E-xVSB system performs well under serious dynamic multipath reception environment.

• Journal of Dental Anesthesia and Pain Medicine
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• v.24 no.5
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• pp.361-366
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• 2024

Orthognathic surgery often requires intraoral orthodontic appliances that are fixed directly to the bone, which can complicate nasotracheal intubation if the devices protrude into the nasal cavity. This case report describes a 19-year-old man scheduled for elective orthognathic surgery who experienced recurrent cuff tears of the endotracheal tube during nasotracheal intubation due to protruding orthodontic screws in the palate. Despite initial attempts at nasotracheal intubation through the left nostril, the cuff of the 7.0 mm internal diameter (ID) Ring, Adair & Elwyn (RAE) tube repeatedly ruptured, with identical rupture patterns observed. Facial CT revealed that the orthodontic screws had protruded into both nasal cavities with significant visibility in the sagittal, coronal, and transverse views. Fiberoptic examination of the left nasal passage identified a firm protrusion below the inferior turbinate, corresponding to the location of the screw, which likely caused the cuff tears. Intubation was successfully performed via the right nostril during the fiberoptic examination. This case highlights the critical importance of evaluating intraoral corrective devices using comprehensive craniofacial imaging before anesthesia induction, as well as conducting fiberoptic examinations during intubation to avoid complications and ensure patient safety.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.685-688
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• 2016

SBAS(Satellite Based Augmentation System) broadcasts the correction message based on satellite communication to improve the positioning accuracy of GNSS user. For this reason, SBAS is actively being utilized on navigation part. To apply SBAS to navigation part, it should satisfy not only accuracy but also integrity, continuity, availability, coverage requirements and so on. Since SBAS reference station is the base infrastructure of SBAS, it is the main factor to determine the environment, position, and geometry of reference stations to achieve SBAS service performance. Therefore, a site environmental analysis should be performed prior to the selection of SBAS reference station. In this paper, it performs the environmental analysis of NDGPS(Nationwide Differential GPS) reference station sites on the premise that SBAS reference station will be co-operated in the same site of NDGPS operated by MOF(Ministry of Oceans and Fisheries). The environmental analysis is conducted as carrying out the visibility analysis of GPS satellite and interference analysis. This paper also presents the brief procedures and requirements for site survey of SBAS reference station.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.6
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• pp.185-201
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• 2018

Road lighting is highly preferred as the major nighttime road safety countermeasures. When it comes to the pole-type road lighting, as it's installed at a certain height from the road surface, the driver is dazzled by the light source, interrupting the driver's visibility and furthermore, the light leaks to the area outside the road boundary, worsening the energy efficiency as well as generating the light pollution to the surrounding environment including the animals and plants. The study developed the low-level lighting systems, so it is possible to prevent the lights from being strayed, so there is no any side effects in terms of the sleep deprivation. The study compared the performance as the lightings between low-level lightings and conventional pole based lighting systems. As the results, the low-level lighting systems showed the higher performance in terms of average surface luminance, uniformity, glare compared to the conventional lighting systems.

• International Journal of Knowledge Content Development & Technology
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• v.14 no.1
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• pp.53-73
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• 2024

The purpose of the study is to investigate the development of institutional repositories in university libraries in Nigeria. The study adopted a survey research design. Online questionnaire, IRs investigation, and interview methods were used to collect data from the 21 university libraries that have developed IRs in Nigeria. The study revealed that only few universities have successfully developed open access IRs to preserve and manage their intellectual outputs emanating from their universities. Contents such as journal articles, theses/dissertations, and conference / workshop papers were found to be the most popular contents that are hosted in the IRs. The interview revealed that although few respondents mentioned having IR policy statements in areas such as access policy, submission policy, preservation policy, content policy and copyright policy, the majority mentioned not having any defined policy in their IR. Also in the interview, inadequate fund, challenge of collecting contents for the IR, shortage of skilled ICT personnel, and inadequate facilities were the most mentioned challenges encountered in the development of IRs in Nigeria. Findings from this study will inform University Librarians, university management and policy makers on the need to provide the necessary infrastructure and formulate policies for smooth development of institutional repositories to make research visible globally. The results will therefore provide important data and insight into the development of institutional repositories in university libraries in the context of developing countries.

• Journal of Internet Computing and Services
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• v.10 no.6
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• pp.51-79
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• 2009

Today the service industry is growing, and differentiated services for marketing and service quality is emerging as a serious problem. Until now, the WebCam is used for observation, and the negative aspects, such as from a human rights issue has become. Discipline and Punish is not to use a webcam to customer satisfaction research is needed. Therefore, wireless monitoring in WebCam service quality of the service reconfiguration and service quality factors for the configuration of the customer's preference regarding how research was recognized. Configuration of the service quality factors WebCam service customer satisfaction and customer loyalty was to identify factors that affect. These services to study the correlation between the quality variables WebCam provides wireless monitoring services for the preschool and children, a survey of the house. Configuring a wireless monitoring service quality in order to research the factors WebCam video quality and transmission speed, mobility and portability, convenience, visibility, reliability, and the interaction of the castle set. Severely and video quality and transmission speed, visibility, reliability, customer satisfaction, the interaction factors are said. Inclination to participate in social issues, innovation, digital devices that use a skilled, depending on the difference in the service quality has been confirmed. However, the age and quality of service awareness and job types showed a low correlation, and the marketing of these results will be discussed and how that can be used.