• The Journal of the Acoustical Society of Korea
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• v.38 no.2
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• pp.161-167
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• 2019

In this paper, the performance verification of an around-view sonar and an excavation depth measuring sonar applicable to track-based ROVs (Remotely Operated underwater Vehicles) for heavy duty work is studied. For the performance verification, an experiment is carried out in a water tank and at sea by attaching the around-view sonar and the excavation depth measuring sonar for a heavy work ROV. In the case of the around-view sonar, image sonars are mounted on ROV in four directions (front, back, left and right) and in the case of the excavation depth measuring sonar, the same kind of MBES (Multi Beam Echo Sounder) is mounted on the front of the ROV. The result of an operation test of the ROV equipped with these sonars shows that the sonar systems are rarely affected by high turbidity due to sedimentation during the operation. In the case of the around-view sonar, it is possible to see rock formation, gravel and sandbank 30 m ahead of the ROV. It is confirmed that the excavation depth can be measured after the ROV has performed the excavation. This experiment demonstrates that the ROV can improve the efficiency of the work by utilizing the around-view sonar and the excavation depth measuring sonar.

• Korean Chemical Engineering Research
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• v.57 no.3
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• pp.400-407
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• 2019

Oxy-combustion with a circulating fluidized bed (Oxy-CFBC) technology has been paid attention to cope with the climate change and fuel supply problem. In addition, Oxy-CFBC technology as one of the methods for carbon dioxide capture is an eco-friendly that can reduce air pollutants, such as $SO_2$, NO and CO through a flue gas recirculation process. The newly developed $100kW_{th}$ pilot-scale Oxy-CFBC system used for this research has been continuously utilizing to investigate oxy-combustion characteristics for various fuels, coals and biomasses to verify the possibility of fuel diversification. The anthracite is known as a low reactivity fuel due to a lot of fixed carbon and ash. Therefore, this study aims not only to improve combustion efficiency of an anthracite, but also to capture carbon dioxide. As a result, compared to air-combustion of sub-bituminous coal, oxy-combustion of anthracite could improve 2% combustion efficiency and emissions of $SO_2$, CO and NO were reduced 15%, 60% and 99%, respectively. In addition, stable operating of Oxy-CFBC could capture above 94 vol.% $CO_2$.

• Journal of Applied Biological Chemistry
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• v.63 no.4
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• pp.387-392
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• 2020

Pseudomonas tolaasii is a pathogen causing brown blotch disease in cultivated mushrooms. In previous study, various strains of P. tolaasii were isolated from the mushrooms with disease symptoms and they were further divided into Ptα, Ptβ, and Ptγ subtypes according to the 16S rRNA gene analysis. To investigate the secretion of peptide toxins, tolaasin and its analog peptides, culture extracts of Pt group strains were analyzed by gel permeation chromatography. Those of Ptα subtype strains contained two chromatographic peaks, band A and B. Meanwhile, those of Ptβ and Ptγ subtype strains contained mainly band A component and a little of band B. Molecular weights of toxic peptides of culture extracts were measured by MALDI-TOF mass spectrometry. In Ptα subtype strains, the peptide compositions of band A and B were same including tolaasin I (1,987 Da), tolaasin II (1,943 Da), and its two analog peptides, 1,973 Da and 2,005 Da. The strains of Ptβ and Ptγ subtype secreted many components of MW 1,100-1,200 Da, but they did not synthesize any tolaasin-like peptides. These results suggest that the only Ptα subtype strains secrete tolaasin and its analog peptide toxins and the strains of Ptβ and Ptγ subtypes have different pathogenic characters causing brown blotch disease.

• Korean Journal of Veterinary Service
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• v.44 no.2
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• pp.73-83
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• 2021

Although many swine farms continuously vaccinated to sow to prevent Porcine epidemic diarrhea(PED), PED has occurred annually in swine herds in Jeonbuk province, Korea. In the present study, the small intestine and feces samples from 17 farms where severe watery diarrhea and death of newborn piglets occurred in 2019 were collected, amplified by RT-PCR and determined the complete nucleotide sequences of the spike (S) glycoprotein genes of nine Jeonbuk PEDV isolates. The spike (S) glycoprotein is an important determinant for molecular characterization and genetic relationship of PEDV. These nine complete S gene isolates were compared with other PEDV reference strains to identify the molecular diversity, phylogenetic relationships and antigenicity analysis. 9 field strains share 98.5~100% homologies with each other at the nucleotide sequence level and 97.3~100% homologies with each other at the amino acid level. The nine Jeonbuk PEDV isolates were classified into G2b group including a genetic specific signal, S-indels (insertion and deletion of S gene). In addition, comparisons the neutralizing epitopes of S gene between 9 field strains and domestic vaccine strains of Korea mutated 12-15 amino acids with SM-98-1 (G1a group) and mutated 0-3 amino acids with QIAP1401 (G2b group). Therefore, the development of G2b-based live vaccines will have to be expedited to ensure effective prevention of endemic PED in Korea. In addition, we will need to be prepared with periodic updates of preventive vaccines based on the PEDV variants for the re-emergence of a virulent strain.

• Journal of Chest Surgery
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• v.43 no.6
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• pp.829-832
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• 2010

A primary pleural small cell carcinoma is an extremely rare disease. Because of a newly developed metastatic lesion, we performed an operation on a patient who had undergone a right upper lobe lobectomy for adenocarcinoma 3 years previously. We resected the pleural lesion and the pathology report showed that it was not a metastatic lesion, but rather, it was a primary pleural small cell carcinoma. So we reported this case and we review the relevant literature.

• Resources Recycling
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• v.9 no.5
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• pp.22-27
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• 2000

Iron oxide produced form the pickling process at the cold rolling mill in iron & steelmaking industry, use for raw material of electronic an colorant product. Recently, decreasing of the chlorine content in iron oxide is demanded at the market. In this study, under the field test of the spray roaster and the screw conveyer for dechlorination, the experiments of the chlorine content in iron oxide were investigated. From the results of experiment, the chlorine content in iron oxide can be reduced to 1,100 ppm from the spray roaster and, 383 ppm from the screw conveyer.

• Journal of Sericultural and Entomological Science
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• v.37 no.2
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• pp.167-171
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• 1995

To develope a microbial pesticide for the control of mulberry longicorn beetle, Apriona germari, Beauveria spp. were isolated from the infected Apriona germari larvae. The morphology of Beauveria spp. was observed by phase contrast and scanning electron microscope. In addition, the Beauveria spp. isolated from Apriona germari were identified by the random amplification of polymorphic DNA using polymerase chain reaction. The results showed that the Beauveria spp., SFB-1A and SFB-3A, isolated from Apriona germari were identified with B. bassiana and B. brongniartii, respectively, suggesting that the random amplification of polymorphic DNA is effective for the identification of Beauveria spp.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.932-933
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• 2011

지속적인 경제발전 및 이상 기후변화 등으로 인한 전력수요의 지속적 증가로 2010년에 최대 66,511MW, 2011년에는 4월 현재까지 최대 68,154MW를 기록하고 있어 원활한 전력공급을 위한 전력설비의 지속적인 건설이 요구되고 있다. 그러나 건설지역 주민들의 민원 등으로 인해 건설은 갈수록 어려워지고 있는 실정이다. 한전에서는 변전소 건설의 경제성을 확보하고 변전소 건설 부지면적 및 건물면적을 최소화한 154kV Compact형 변전소를 개발하게 되었다. 이를 위해서는 변전소 면적의 상당부분을 차지하고 있는 변압기 설치면적 최소화가 필수적이다. 이를 위해 변압기 설치공간 최소화하고 냉각효율 및 민원 등을 고려한 냉매냉각방식(HCFC:Hydro Chloro Carbons, 수소화염화불화탄소)의 적용을 추진하였으나 HCFC는 오존파괴물질로 규정되어 생산과 수입이 규제될 예정으로 한전은 냉매냉각방식의 대안으로 기존 수냉식 냉각방식의 환경문제, 냉각탑 관리의 어려움 등과 물 비산에 따른 상하수도 이용요금 부담 등의 단점을 개선한 공냉형 수냉식 냉각방식을 개발하게 되었다. 본 논문에서는 154kV 변압기 공냉형 수냉식 냉각방식의 개발내용 및 운전현황에 대해 기술하고자 한다.

• Journal of KIISE
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• v.44 no.10
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• pp.1081-1086
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• 2017

A program analysis of a large-scale open-source software repository has a significant meaning in that it allows us to examine the changes and improvements of the software in repositories, and this brings more reliable results based on a large amount of programs. In this paper, we introduce a new static analysis framework WALABOA, which enables a scalable static analysis of large-scale software repositories. In addition, we show new findings from applying WALABOA, together with a module comparing the analysis results from a static analysis and a dynamic analysis, in evaluation of the field-based analysis, one of JavaScript static analysis techniques used in WALA.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.477-478
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• 2011

전기, 전자분야에 반도체가 폭넓게 사용됨에 따라 발 변전소에서 Noise에 의한 보호계전기 오동작 사례가 늘어나고 있어, 이것을 효과적으로 차단하고 설비의 오동작을 예방할 수 있는 필터개발이 필요 하였다. 현재 시중에서 사용하고 있는 Ferrite Filter는 일반 가전 및 OA를 대상으로 개발하였기 때문에 송변전계통의 변전소에서 발생하는 Noise와 차단 영역이 다르다. 따라서 송변전설비 보호계전기의 오동작원인을 분석하고, 변전소에서 발생하는 Noise의 형태를 측정하여 그것을 차단하기에 적합한 Clamp형의 Ferrite Filter를 개발하였다. Ferrite Filter는 재질에 따라 고주파 차단 영역이 결정된다. 일반적인 전자설비에 사용하는 니켈계(Ni-Zn) 재질의 Filter는 수MHz~수GHz 영역이며, 변전소에 주로 발생하는 고주파 수KHz~수MHz 영역은 망간계(Mn-Zn) 재질을 혼합하여 만들었다. 개발한 Filter의 성능 확인을 위해 공인시험기관인 KERI(한국전기연구원)에서 다양한 형태로 고주파 차단 특성 시험을 시행한 결과, 망간계와 니켈계 Ferrite Filter를 직렬로 설치함으로서 Noise를 효과적으로 차단함을 확인 하였고 5개소에 2개월간시범적용을 통하여 그 성능을 검증하였다. 본 연구결과는 Clamp형 Ferrite Filter의 기술적 한계로 여겨졌던 고주파 차단특성을 발변전소 등의 전력설비에서 발생하는 대역까지 확대하였으며, 경제적으로도 기존의 L-C Filter 대비 약 4%의 비용으로 설치할 수 있어 그 비용을 획기적으로 절감하였고, 설비의 정지 없이 언제든지 간편하게 설치할 수 있어 현장에서 적용하기에 매우 유용하다. 그 성능을 지속적으로 향상시켜 많은 분야에서 활용할 수 있도록 추가적인 연구개발이 필요할 것으로 판단된다.