• 한국화재소방학회논문지
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• 제28권6호
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• pp.58-61
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• 2014

불꽃감지기는 열, 연기식 감지기보다 화재검출이 빠르고 높은 층고에서도 효과를 발휘할 수 있어 가격이 고가임에도 많이 사용되고 있다. 불꽃감지기의 동작신뢰성 향상을 위해 성능시험, 감도시험, 옥내 외구분, 제품사후관리나 관리감독에 대하여 외국 기준과 비교하였다. 그 결과 유럽과 미주지역에는 부작동시험, 옥내 외구분이 없고 감도조정 기준이 있다. 성능시험중 작동관계는 제품의 신뢰성이나 내구성에 중심을 두고, 부작동시험은 현장의 환경에 맞게 감도를 조정할 수 할 수 있게 한다. 또한 제품사후관리 조항 추가 및 제품에 대한 품질관리 책임과 인증기관의 관리시스템, 특수감지기의 제도권 도입, 상호 관련기구들의 규정 마련이 필요하다.

• 한국통신학회논문지
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• 제34권2C호
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• pp.234-241
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• 2009

TETRA Enhanced Data Service (TEDS) 는 기존의 협대역 ETSI TETRA Release 1 표준안을 개선하여 주파수 선택적인 페이딩 채널에서 고속의 패킷 데이터 전송이 가능한 표준 규격이다. TEDS 표준에서 사용하는 M-QAM 변조방식의 성능은 채널 추정 성능에 크게 영향을 받는다. 본 논문에서는 Per-Survivor Processing (PSP) 기법을 사용하여 고속 채널 환경에 적합한 새로운 decision-directed 채널 추정 기법을 제안한다. 제안된 채널 추정기법은 이동 환경에서 기존 파일럿 신호 기반의 채널 추정 기법에 비해 TETRA 수신 성능을 향상시킬 수 있음을 전산 모의 실험을 통해 보인다.

• 대한기계학회논문집B
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• 제34권10호
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• pp.907-916
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• 2010

고온형 연료전지인 MCFC 발전시스템에 가스터빈, 유기매체 랜킨 사이클, 순산소 연소 사이클 등 다양한 하부 사이클을 추가한 통합시스템들의 성능을 비교 해석하였다. MCFC 시스템의 성능과 운전조건을 바탕으로 하여 각 추가 시스템의 주요 설계 변수 변화에 따른 통합시스템의 성능 변화를 해석하였고 이로부터 각 시스템의 최적 성능을 도출하였다. 각 시스템을 비교하여 MCFC와 최적의 결합을 나타내는 시스템을 분석하였는데, MCFC/OXY 시스템이 MCFC 단독 시스템에 비하여 가장 큰 출력 증가를 나타내었으며, MCFC/GT 시스템의 효율 증가가 가장 큰 것으로 나타났다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2005년도 춘계종합학술대회
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• pp.804-807
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• 2005

본 논문에서는 Digital IF(Intermediate Frequency) 기술을 이용한 Up/Down 변환기를 설계하고, 이에 대한 성능을 평가 하였다. Digital IF 기술을 사용하는 이유는 passive 소자로 구성되어진 IF 주파수 영역은 고정되어진 한 주파수 밖에 사용하지 못하지만, Digital IF로 구성되어지면 보드의 외형적인 변경 없이 다양한 통신 주파수 영역에서 유연성 있게 사용이 가능하게 된다. 이러한 구성은 기존의 아날로그 헤테로다인 방식에 비하여 높은 유연성을 가지며, 우수한 성능향상을 보여준다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2006년도 춘계종합학술대회
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• pp.961-965
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• 2006

본 논문에서는 Digital IF(Intermediate Frequency) 기술을 이용한 Up/Down 변환기를 설계하고, 이에 대한 성능을 평가하였다. Digital IF 기술을 사용하는 이유는 passive 소자로 구성되어진 IF주파수 영역은 고정되어진 한 주파수 밖에 사용하지 못하지만, Digital IF로 구성되어지면 보드의 외형적인 변경 없이 다양한 통신 주파수 영역에서 유연성 있게 사용이 가능하게 된다. 이러한 구성은 기존의 아날로그 헤테로다인 방식에 비하여 높은 유연성을 가지며, 우수한 성능향상을 보여준다.

• 대한원격탐사학회지
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• 제18권3호
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• pp.147-153
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• 2002

The real-time reception and recording of down-link mission data from a satellite requires the highest reliability because the data lost in receiving process cannot be recovered. The data receiving and recording system has moved from a set of dedicated hardware and software components to commercial-off-the-shelf (COTS) components in order to reduce the system cost as well as to upgrade the system easily for handling other satellite data. The use of COTS hardware and middleware components prevents the system developer from correcting or modifying the internal operations of the COTS components, and hence, instant performance degradation of the COTS components which affects the reliable data acquisition must be covered by a software algorithm. This paper introduces the instant performance problem of a COTS data recording device which leads to the data loss in the real-time data reception and recording process. As a result, the requirement of the modification of the conventional data read/write technique is issued. In order to overcome the data loss problem due to the use of COTS components and the conventional software technique, a new algorithm called a software buffering technique is proposed. The experiments show that the application of the proposed technique results in reliable real-time reception and recording of high speed serial data.

• 급식외식위생학회지
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• 제1권1호
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• pp.45-51
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• 2020

This study sought to understand the requirements of registered institutions and parents of beneficiary children's through a satisfaction survey conducted at Center for Children's Foodservice Management (CCFSM) and to improve quality to create a model example of site-based meal safety management in accordance with population trends. In 2019, the comprehensive satisfaction level of the director and parents rose 2.4 points and 2.9 points, respectively, compared to the previous year, and the comprehensive satisfaction level of the director and parents continued to rise from 2015 to 2019. The gap between the highest and lowest institutions is narrowed to 13.5 points year-on-year from 21.4 points. National Institute of Food and Nutrition Service will need to make efforts to upgrade regional centers through (Human Resource Development(HRD) training to strengthen their job-specific capabilities and minimize the standard deviation of each center. Since local centers are distributed across the country and have field-oriented service support systems, CCFSM will need to manage the healthy eating habits of the underprivileged, provide information necessary to establish proper eating habits, strengthen education, and establish a customized food safety service system.

• 한국IT서비스학회지
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• 제21권4호
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• pp.75-90
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• 2022

From the past to the present, reviews have had much influence on consumers' purchasing decisions. Companies are making various efforts, such as introducing a review incentive system to increase the number of reviews. Recently, as various types of reviews can be left, reviews have begun to be recognized as interesting new content. This way, reviews have become essential in creating loyal customers. Therefore, research and utilization of reviews are being actively conducted. Some studies analyze reviews to discover customers' needs, studies that upgrade recommendation systems using reviews, and studies that analyze consumers' emotions and attitudes through reviews. However, research that predicts the future using reviews is insufficient. This study used a dataset consisting of two reviews written in pairs with differences in usage periods. In this study, the direction of consumer product evaluation is predicted using KoBERT, which shows excellent performance in Text Deep Learning. We used 7,233 reviews collected to demonstrate the excellence of the proposed model. As a result, the proposed model using the review text and the star rating showed excellent performance compared to the baseline that follows the majority voting.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권9호
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• pp.3029-3042
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• 2022

For over half a century, the United States (US) and its coalition military aircrafts have been using Ultra High Frequency (UHF) band analog modulation (AM) radios in ground-to-air communication and short-range air-to-air communications. Evolving from this, since 2007, the US military and the North Atlantic Treaty Organization (NATO) adopted HAVE QUICK to be used by almost all aircrafts, because it had been revealed that intercepting and jamming of former aircraft communication signals was possible, which placed a serious threat to defense systems. The second-generation Anti-jam Tactical UHF Radio for NATO (SATURN) was developed to replace HAVE QUICK systems by 2023. The NATO Standardization Agreement (STANAG) 4372 is a classified document that defines the SATURN technical and operational specifications. In preparation of this future upgrade to SATURN systems, in this paper, the SATURN technical and operational specifications are reviewed, and the network synchronization, frequency hopping, and communication setup parameters that are controlled by the Network (NET) Time, Time Of Day (TOD), Word Of Day (WOD), and Multiple Word of Day (MWOD) are described in addition to SATURN Edition 3 (ED3) and future Edition 4 (ED4) basic features. In addition, an anti-jamming performance analysis (in reference to partial band jamming and pulse jamming) and the time delay queueing model analysis are conducted based on a SATURN transmitter and receiver assumed model.

• 한국지진공학회논문집
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• 제20권7_spc호
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• pp.509-516
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• 2016

Secure operation of hospitals during and right after earthquake is essential. Past lessons from earthquake damages have shown that most of the injured and the death occurred within 30 minutes after earthquake and the portion of nonstructural damage has become significant. However, hospital buildings in Korea have not prepared fully to address such rising issues. This paper is to study what type of damage patterns are related to hospital buildings and how to develop a preparedness plan to keep hospitals operational at all earthquakes if possible. This paper first reviews on past earthquake damages reported as critical to hospital buildings while classifying them into four groups: (1) structural element; (2) architectural-nostructural element; (3) medical equipments and contents; and (4) utility facility. Upon such classification, some detailed concerns can be specified under each group explicitly. Then a hierarchy for hospital building is also developed for the classified groups, which enables us to identify required things for the enhancement of seismic performance of hospital building that consists of heterogeneous elements. To upgrade the level of seismic performance for existing hospital buildings, the concept of performance-based approach can be adopted to address the heterogeneous problems in a systematic and stepwise manner. Finally a conceptual framework for the seismic risk assessment for hospital building is proposed toward the seismic enhancement of hospital buildings using performance-based approach.