• JOURNAL OF ELECTRICAL WORLD
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• no.5 s.15
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• pp.37-51
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• 1969

이 원고는 표기와 같이 Electrical World지의 오스트레일리아 및 동남아시아관계 편집자인 W. Diesendorf씨의 동남아시아 전기사업의 시찰시행기이다. 주로 전기사업에 있어서의 최근의 동향 및 설비확장상황에 대하여 조사하였고 그 조사대상국은 서말레이시아, 태국, 필리핀, 홍콩 및 싱가포르이다. 이들 제국에서는 민간 및 국제자금, 세계은행차관과 업자차관을 자금원으로 하여 전력설비의 건설을 진행하고 있다. 홍콩은 과거에 722.5Mw의 혹$\cdot$운(Hok Un)발전소로 인한 대기오염 때문에 곤란을 겪어 왔으나 중화전등전력회사와 ESSO의 공동출자로 설립된 반도전력회사(PEPC)의 칭$\cdot$이(Tsing Yi) 발전소가 베이스부하발전을 맡게 되고 시내로부터 멀리 떨어져 있는 위치와 높은 연출에 의하여 1969년도에는 심한 대기오염을 완하하기로 계획되어 있다. 싱가포르는 1971년까지 240Mw의 쥬롱(Jurong)발전소가 운전을 개시하기로 되어 있다. 싱가포르는 $5\~6$년마다 배증하는 부하를 가지고 있는데 이것은 주로, 철강, 시멘트 및 섬유공업에 의한 것이다. 말레이시아는 포오트$\cdot$딕슨(Port Dickson)발전소의 제1기 60MwX4가 $1969\~1972$년에 운전을 개시하기로 되어 있고 제2기는 수개의 유니트가 구성될 예정이며 카메론고지수력개발계획이 진행되고 있다. 태국에서는 유명한 꾸아에$\cdot$야이(Quae Yai)강의 칸$\cdot$리엥(Kany Rieng)에서 200Mw를 개발하기로 되어 있으며 그 제1기 공사는 1973년에 시작될 예정이다. 1975년까지 얀히이(Yanhee)전기청의 부하는 400Mw의 원자력발전소의 건설을 가능케 할 것으로 생각되고 있다. 마닐라에서는 중유화력의 가아드너(Gardener)발전소의 건설을 진행시키고 있으며 첫 번째의 165Mw의 유니트는 곧 운전을 개시할 것이며 두 번째 유니트도 1969년도에 운전이 개시될 예정이다. 마닐라전기회사는 연율 $12\~13\%$의 부하성장율을 흡수할 수 있도록 설비확장공사를 추진시키고 있다. 지리적으로만 보더라도 우리나라와 가까운 동남아시아의 전력설비현황을 알기 위한 참고로서 이 원고를 소개하기로 한다.

• Journal of Broadcast Engineering
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• v.23 no.2
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• pp.316-319
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• 2018

When a terrestrial UHD broadcasting service and a mobile HD broadcasting service are provided using the PLP function provided by ATSC 3.0 and domestic UHD broadcasting standard, a small amount of data may be additionally transmitted to further provide high quality UHD-3D broadcasting service. The left and right images of the stereoscopic image are input, one view image is encoded by the SHVC method, and the other view images are encoded by the SHVC method of the two-view cross-referencing method. However, since the base layers (BL) of the two encoders are mutually common, the two encoders correspond to encoders that generate one BL stream and two enhancement layer (EL) streams. The average encoding efficiency is 16% more efficient compared to the third independent HEVC encoding for the UHD-3D broadcast service. The proposed scheme reduces the fluctuation of PSNR per image frame and increases the image quality of minimum PSNR frame by 0.6dB.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.512-515
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• 2010

SIGINT(SIGnal INTelligence) includes several parameters intercepted by measurement and analysis of the RF(Radio frequency) signal from free space. One of the important parameters is frequency information. Expecially, in order to perform instantaneous frequency measurement of Radar and Missile seeker's RF signals, we use dedicated RF modules as a DFD(Digital Frequency Discriminator) to provide frequency information by measurement of the relative phase difference between signals via intended RF delay lines. It must measure and provide realtime based frequency information on short pulsed RF signal up to 100 nSec or less. This document proposes Ultra wideband DFD consisted of a RF input section of Wideband 4 channel RF delay line and correlator, a digital processing section to measure and provide frequency information from I/Q signal, and a frequency calibration section. Also, it will show design suitability based on test results measured under test condition of very short input pulse signals.

• Fire Science and Engineering
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• v.24 no.1
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• pp.134-139
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• 2010

According to the "Yearbook of disaster response, fire safety and fire statistics (NEMA: National Emergency Management Agency)", approximately 34% of all fire is interior fire such as hotel, restaurant and residence and more than 53% of which is occurring in the kitchen. The evaluation of fire extinguishing system in the kitchen is performed in accordance with the "Korea Fire Equipment Inspection Standard (KOFEIS 0101-1)" which is using one environmental condition. However, only using one environmental condition is not enough to evaluate the performance of the automatic fire extinguisher in kitchen fire. So the study of fire detecting characteristic about various environmental condition needs. In this study, the numerical analysis is carried out about detecting time characteristic for various range's surrounding environment. As a result, it showed up to 100 s difference in the detection time depending on the position of the range. And detecting time also showed difference for on-off hood operation. From this results, it can be verify and improve the evaluation standard for the fire extinguishing system in kitchen fire.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.4
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• pp.671-678
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• 2019

The semantic information provided through the semantic-based IoT system will produce new high value-added products that are completely different from what we have known and experienced. From this point of view, the key issue of current IoT technology and applications is the development of an intelligent IoT platform architecture. The proposed system collects the IoT data of the sensors from the cloud computer, converts them into RDF, and annotates them with semantics. The converted semantic data is shared and utilized through the ontology repository. We use KT's IoTMakers as a cloud computing environment, and the ontology repository uses Jena's Fuseki server to express SPARQL query results on the web using Daum Map API and Highcharts API. This gives people the opportunity to access the semantic IoT mash-up service easily and has various application possibilities.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.43-43
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• 2022

유해 조류 대발생은 전국 각지의 인공호소나 하천에서 다발적으로 발생하며, 경관을 해치고 수질을 오염시키는 등 수자원에 부정적인 영향을 미친다. 본 연구에서는 인공호소에서 발생하는 유해 조류 대발생을 예측하기 위해 심층학습 기법을 이용하여 예측 모델을 개발하고자 하였다. 대상 지점은 대청호의 추동 지점으로 선정하였다. 대청호는 금강유역 중류에 위치한 댐으로, 약 150만명에 달하는 급수 인구수를 유지 중이기에 유해 남조 대발생 관리가 매우 중요한 장소이다. 학습용 데이터 구축은 대청호의 2011년 1월부터 2019년 12월까지 측정된 수질, 기상, 수문 자료를 입력 자료를 이용하였다. 수질 예측 모델의 구조는 다중 레이어 퍼셉트론(Multiple Layer Perceptron; MLP)으로, 입력과 한 개 이상의 은닉층, 그리고 출력층으로 구성된 인공신경망이다. 본 연구에서는 인공신경망의 은닉층 개수(1~3개)와 각각의 레이어에 적용되는 은닉 노드 개수(11~30개), 활성함수 5종(Linear, sigmoid, hyperbolic tangent, Rectified Linear Unit, Exponential Linear Unit)을 각각 하이퍼파라미터로 정하고, 모델의 성능을 최대로 발휘할 수 있는 조건을 찾고자 하였다. 하이퍼파라미터 최적화 도구는 Tensorflow에서 배포하는 Keras Tuner를 사용하였다. 모델은 총 3000 학습 epoch 가 진행되는 동안 최적의 가중치를 계산하도록 설계하였고, 이 결과를 매 반복마다 저장장치에 기록하였다. 모델 성능의 타당성은 예측과 실측 데이터 간의 상관관계를 R2, NSE, RMSE를 통해 산출하여 검증하였다. 모델 최적화 결과, 적합한 하이퍼파라미터는 최적화 횟수 총 300회에서 256 번째 반복 결과인 은닉층 개수 3개, 은닉 노드 수 각각 25개, 22개, 14개가 가장 적합하였고, 이에 따른 활성함수는 ELU, ReLU, Hyperbolic tangent, Linear 순서대로 사용되었다. 최적화된 하이퍼파라미터를 이용하여 모델 학습 및 검증을 수행한 결과, R2는 학습 0.68, 검증 0.61이었고 NSE는 학습 0.85, 검증 0.81, RMSE는 학습 0.82, 검증 0.92로 나타났다.

• Membrane Journal
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• v.16 no.1
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• pp.59-67
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• 2006

Biodegradable amphiphilic polymer was synthesized for removing hydrophobic pollutants(phenol, 4-nitrophenol, benzene, and toluene) and metal ions ($Cs^{+},\;Mg^{2+},\;Cu^{2+},\;Ni^{2+}$, and $Cr^{3}$). The methoxy poly(ethylene glycol)s with different molecular weights (1,100 and 5,000) were used as a hydrophilic segment. The rejection ratio improved in the relatively high molecular weight of MPEG. The rejection ratio of biodegradable nanoparticles without pollutants was over 98%. In removal of hydrophobic pollutants, the rejection ratio increased with the hydrophobic properties. The electron valence affects the rejection ratio of metal ions, indicating rejection ratio was ordered as $3^{+}>2^{+}>1^{+}$.

• Korean journal of applied entomology
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• v.61 no.2
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• pp.293-297
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• 2022

Korean thistle (Cirsium setidens Nakai), also called Gondre, is an edible perennial herbaceous plant. A new occurrence of aphids has been confirmed on Korean thistle, which is expected to damage crops. The control effect of organic materials was tested to develop an eco-friendly control method for aphid. Pyrethrins+paraffinic oils exhibited a 98% control effect, pyrethrins+matrine+pyroligneous acid showed a 95% control effect, and azadirachtin+rotenone was found to have a 75% control effect. Pyrethrins appear to be the most effective; no damage (phytotoxticity) was caused with organic materials spraying.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.3
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• pp.554-563
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• 1999

For the purpose of elucidating the polymerization modes of dual-cure restorative materials and comparing them with single-cure restorative materials, a study was performed on the light-cured composite resin, dual-cure composite resin, dual-cure glass ionomer cement and chemical-cure glass ionomer cement. By measuring the microhardness of each material at 0mm, 1mm and 3mm depth during initial 24 hours with predetermined interval, the state of polymerization and degree of conversion was indirectly evaluated for each material, and obtained results are as follows : 1. All of four materials tested showed significant increase in microhardness after 24hrs compared with just after curing starts. 2. In all materials except Ketac-fil, there showed a significant difference in microhardness between each depth at each time interval. 3. In the test of lap time till final curing for each material, the polymerization process was revealed to last longer in the dual-cure type materials than in single-cure type materials at 3mm depth. Based on the results above, it was demonstrated with materials of dual-cure mode that the degree of conversion increases by successive curing reactions even in the deeper layers where sufficient curing light is impermeable.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.1988-1993
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• 2013

The aims of this study were to investigate the quality characteristics of yellow layer cake added with Sparassis crispa powder that were abundant in dietary fiber, and also to determine the most suitable amount of added S. crispa powder. Dried powder of S. crispa containing 61.8 g/100 g insoluble dietary fiber was added to the cake batter in Baker's percentage of 1%, 2%, 4%, and 8%. Cake batter containing 1% and 2% S. crispa powder showed similar pH, specific gravity, and viscosity values to the batter without S. crispa powder (control). As the amount of added S. crispa power increased, the volume, specific volume, baking loss, and brightness (for both crust and crumb) of the cake containing the powder tended to decrease. A greater amount of added S. crispa powder resulted in a decrease in hardness, gumminess, and chewiness of the cake containing the powder and also reduced the changes in hardness of the cake during 8 days of storage. The sensory analysis showed that cake containing 2% S. crispa had several desirable kinds of sensory attributes, such as color, flavor, taste, and texture compared to the control; whereas an addition of more than 2% S. crispa deteriorated the sensory quality of the cake. These results suggest that the most suitable amount of added S. crispa powder for preparing yellow layer cake was 2% in Baker's percentage.