• 한국항행학회논문지
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• 제17권1호
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• pp.1-8
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• 2013

항공교통관리에 있어서 ADS-B(Automatic Dependent Surveillance-Broadcast)와 multilateration은 국제민간항공기구에서 지정한 차세대 시스템 중 핵심기술이다. 그러나 오늘날, 모든 항공기가 ADS-B를 장착하고 있지는 않다. ADS-B 미장착 항공기의 위치 획득을 위해 TIS-B(Traffic Information Service-Broadcast)가 사용되는데, TIS-B는 레이더로부터 획득한 항공기 위치를 제공한다. 본 논문에서는 TIS-B를 대체할 수 있는 2차 감시레이더 신호를 활용한 onboard multilateration 시스템을 제안한다. TIS-B는 레이더 자료를 이용해 항공기 위치를 제공하므로 그 오차가 굉장히 큰 반면, onboard multilateration 시스템은 TDOA(Time Difference of Arrival) 기법을 이용하므로 항공기 위치 오차가 매우 작다. 성능비교 결과, 본 논문에서 제안된 onboard multilateration 시스템이 TIS-B에 비해 공항 인근에서는 37.39%, 공항 200마일 부근에서는 51.61% 성능이 우수한 것으로 나타났다.

• 한국산학기술학회논문지
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• 제15권5호
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• pp.3139-3145
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• 2014

본 논문에서는 가유전체 기판을 이용하여 소형화한 마이크로파 대역의 링 하이브리드 커플러 설계에 대하여 기술한다. 가유전체 기판은 다수의 비어홀을 제 2기판에 삽입하여 유효 커패시턴스를 크게 증가시킨 구조를 갖는다. 가유전체 기판의 유효유전율은 표준형 기판에 비하여 크게 증가하게 되는데, 이에 의하여 동일한 전기적 길이 대비 물리적 길이가 크게 감소하므로 마이크로파 전송선로를 소형화시킬 수 있다. 이런 원리를 마이크로파 무선회로 설계에 적용한 사례를 보이기 위하여 가유전체 기판을 이용하여 3GHz대 링 하이브리드 커플러를 설계하고 실제로 제작 및 측정한 결과를 제시한다. 설계된 소형화된 링 하이브리드 커플러는 표준형에 비하여 전기적 성능은 유사하면서도 65%의 크기를 가진다. 측정된 전력분배비는 각각 -3.05dB와 -3.135dB이며, 두 출력간의 위상차는 동위상일 때 3도, 역위상일 때 176도로 이상적인 값과 매우 유사하다. 이로써 가유전체 기판구조로 소형화된 링 하이브리드 커플러의 설계가 타당함을 보인다.

• Journal of Korean Medical Science
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• 제33권46호
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• pp.290.1-290.11
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• 2018

Background: The role of antidepressants (ADs) in bipolar disorder is long-standing controversial issue in psychiatry. Many clinicians have used ADs as a treatment for bipolar depression, and the selection of therapeutic agents is very diverse and inconsistent. This study aimed to examine recent AD prescription patterns for patients with bipolar disorder in Korea, using the nationwide, population-based data. Methods: This study utilized the Korean nationwide, whole population-based registry data of the year 2010, 2011, and 2013. All prescription data of the ADs, antipsychotics, and mood stabilizers of the sampled patients diagnosed with bipolar disorder (n = 2,022 [in 2010]; 2,038 [in 2011]; 2,626 [in 2013]) were analyzed for each year. Results: Annual prescription rate of ADs was 27.3%-33.6% in bipolar disorder, which was gradually increasing over the 3-year period. The combination pattern of ADs and antipsychotic drugs tended to increase over 3 years. The proportion of females and the prevalence of comorbid anxiety disorder were significantly higher in AD user group in all three years. Among individual ADs, escitalopram was prescribed most frequently, and fluoxetine and bupropion were prescribed to the next many patients. The mean duration of bipolar depressive episodes was 135.90-152.53 days, of which ADs were prescribed for 115.60-121.98 days. Conclusion: Our results show prescription rate of ADs in bipolar disorder was maintained at substantial level and increased in recent 3 years. More empirical data and evidence are needed to establish practical treatment consensuses.

• 한국항행학회논문지
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• 제27권5호
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• pp.552-560
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• 2023

항공기 공중 충돌사고는 대규모 인명 피해를 초래할 수 있는 위험한 사건이다. 이를 예방하기 위해 민간 항공에서는 TCAS(traffic alert and collision avoidance system) 장착을 의무화하였으며, 새로운 기술의 도움을 받아 더욱 정밀하게 발전하고 있다. 한국에서 개인적으로 TCAS 연구를 위한 데이터를 수집하는데는 절차적인 어려움이 있다. 이를 해결하기 위해 ADS-B(automatic dependent surveillance-broadcast)와 Mode-S(mode-select)를 활용하면 TCAS RA(resolution advisory)의 정보 획득이 가능하다. ADS-B Exchange와 Opensky-Network에서 보관중인 데이터베이스를 제공받아 연구에 활용하였으며, 3건의 TCAS RA 발생 사례를 시각화하였다. 또한 2023년 전반기 국내 TCAS RA 발생사례를 분류한 후 그 특징을 분석하였다. 이를 통해 ADS-B와 Mode-S 데이터의 유효성을 확인하고, 발전방향을 모색하였다.

• 방재기술
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• 통권19호
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• pp.17-21
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• 1995

This is to study installation standards of aspirating devices and detectors, which are components of ADS(aspirating fire detection system). The BFPSA(British Fire Protection System Association) code was mainly referred is studying. ADS aspirated air and smoke through the pipe and then checks if there is fire or not. It is now in the limelight because it can early alarm in case of fire and prevent false-alarming.

• International Journal of Human Ecology
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• 제13권2호
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• pp.101-111
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• 2012

Children have become the target of intense and specialized food advertising efforts. This study examines the content of TV food advertising and discussed possible concerns from the perspective of children. A total of 102 ads were collected from two cable networks aimed at children. Most of the food ads used emotional appeals and did not provide information clues such as nutrition values. Ads with high sales pressure and celebrity endorsements appeared frequently and the ads for snack foods and high-carbohydrate bakery products were dominant. Understanding food ads can be a significant indicator to establish the orientation of consumer ad education and build educational programs appropriate for children. The issue that appears conspicuous in child targeted advertising and marketing is the childhood obesity and food advertising relation; subsequently, there is a need to evolve advertising that targets children into a positive educational information source.

• International Journal of Aeronautical and Space Sciences
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• 제13권3호
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• pp.377-385
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• 2012

The Automatic Dependent Surveillance Broadcast (ADS-B) system is a key component of CNS/ATM recommended by the International Civil Aviation Organization (ICAO) as the next generation air traffic control system. ADS-B broadcasts identification, positional data, and operation information of an aircraft to other aircraft, ground vehicles and ground stations in the nearby region. This paper explores the ADS-B based trajectory prediction and the conflict detection algorithm. The multiple-model based trajectory prediction algorithm leads accurate predicted conflict probability at a future forecast time. We propose an efficient and accurate algorithm to calculate conflict probability based on approximation of the conflict zone by a set of blocks. The performance of proposed algorithms is demonstrated by a numerical simulation of two aircraft encounter scenarios.

• 한국해양공학회지
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• 제17권6호
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• pp.16-22
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• 2003

In this paper, the method of determining the economically-optimal design section of rubble mound breakwater, using ADS program, was studied to supplement the deterministic approach. First of all, the design waves are computed, according to the return periods, using the Weibull distribution from the data of waves at the location of the breakwater. In order to take an optimal section, according to the return periods, the ADS program was used. The restriction conditions and objective functions are decided from the references of the specifications and standard manuals for Coastal and Harbor Construction Work. Results from this study support the ADS program as an appropriate method for determining the economically-optimal section of rubble mound breakwater, comparing the construction costs and the initial and damage repair costs for its life time.

• 대한가정학회지
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• 제49권8호
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• pp.97-111
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• 2011

This study aimed to present marketing communication strategy for lifestyle groups. Consumers' preference on advertisement media/information source, advertisement appeal types, and on-line media use were examined by lifestyle groups. This study was executed by web survey and off-line survey. A total of 141 data was obtained and data were analyzed by PASW 18.0. Results were as follows: First, 4 types of lifestyle groups were made up by holistic approach; 'price oriented', 'traditional symbolic', 'positive life', and 'open mind enjoyment'. 'Positive life type' preferred every type of ads media. 'Traditional symbolic type' liked magazine and 'price oriented type' and 'open mind enjoyment type' thought off-line store display more important. For ads appeal types, 'positive life type' preferred social oriented appeal type. Every group except 'price oriented type' preferred emotional appeal type and especially 'open mind enjoyment type' liked the most emotional ads appeal type.

• ETRI Journal
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• 제43권2호
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• pp.324-331
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• 2021

Space-based automatic dependent surveillance-broadcast (ADS-B) is an important emerging augmentation of existing ground-based ADS-B systems. In this paper, the problem of space-based ultra-long-range reception processing of ADS-B signals is described. We first introduce a header detection method for accurately determining the pulse position of a weak ADS-B signal. We designed a signal encoding method, shaping method, and fitness function. We then employed a genetic algorithm to perform high-precision frequency and phase estimations of the detected weak signal. The advantage of this algorithm is that it can simultaneously estimate the frequency and phase, meaning a direct coherent demodulation can be implemented. To address the computational complexity of the genetic algorithm, we improved the ratio algorithm for frequency estimation and raised the accuracy beyond that of the original ratio algorithm with only a slight increase in the computational complexity using relatively few sampling points.