• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.6
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• pp.262-269
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• 2021

This paper conducts an evaluation of the structural performance of the lap splice detail of SD700 headed bar experiment for developing an RC beam with different depths joint details. The experiment variable is lap splice length, yield strength, and end anchorage of main reinforcements. For all specimens, a headed bar was applied to the main reinforcement of the beam with low depth (B2), and the beam with high depth (B1) was applied to the main reinforcement with two splice methods: straight headed bar and 90° hooked-headed bar. The experimental results were that specimens of applying SD500 and SD600 had the results of flexural fracture at the lap splice location, which maximum load was similar. For specimens of appling SD500, the 90° hooked-headed bar of B1, suppressed horizontal cracks in the lap splice section compared to the straight headed bar. Specimens of applying an SD 700 headed bar had the results of brittle anchorage failure. In addition, maximum load was increased with the lap splice length increasing. For specimens of applying SD700 headed bar, test for test maximum load/theoretical load for test development length/design development length were estimated to be 1.30~1.48 for the ACI 318-19 equation, and 1.14~1.30 for the KDS-2021 equation. Thus, ACI 318-19 equation had conservatively greater safety factors as estimated development lengththened.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.7
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• pp.49-57
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• 1994

An efficient approach for the computationtion of the optimum convergence factor is proposed for the LMS algorithm applied to a transversal FIR structure in this study. The approach automatically leads to an optimum step size algorithm at each weight in every iteration that results in a dramatic reduction in terms of convergence time. The algorithm is evaluated in system identification application where two alternative computer simulations are considered for time-invariant and time-varying system cases. The results show that the proposed algorithm needs not appropriate convergence factor and has better performance than AGC(Automatic Gain Control) algorithm and Karni algorithm, which require the convergence factors controlled arbitrarily in computer simulation for time-invariant system and time-varying systems. Also, itis shown that the proposed algorithm has the excellent adaptability campared with NLMS(Normalized LMS) algorithm and RLS (Recursive least Square) algorithm for time-varying circumstances.

• Nuclear industry
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• v.4 no.1 s.17
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• pp.70-71
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• 1984

지난해 11월 4일 국내 각 신문은 캐나다의 토론토발 연합통신의 기사를 연재, $\ulcorner$캐나다 정부는 캔두(CANDU)형 원자로 압력관의 안전도에 대한 우려가 고조되고 있는 가운데 고위관계자들로 구성된 긴급기술조사단을 구성, 캐나다와 한국을 비롯한 외국에 설치된 모든 캔두형 원자로의 안전여부를 조사하기로 했다$\cdots$$\cdots$$\lrcorner$고 크게 보도하여 물의를 일으킨바 있다. 이에 대하여 당사자인 캐나다 원자력공사는 같은 11월 17일자로 해명서를 발표, $\ulcorner$동기사는 월성원자력 발전소의 안전성을 진단하기 위하여 캐나다로부터 조사반을 파견하는 것으로 되어 있으나 이는 전혀 사실과 다르다. 캐나다 원자력공사는 $\ulcorner$픽커링$\lrcorner$원자력발전소의 사고와 관련하여 캔두원자로 보유국에 그 사고내용을 설명하고 최신 원자로의 안전성을 설득시키기 위하여 관계자를 파견할 계획이었으며 이번 우리들의 방한은 그 목적을 위해서 이루어진 것이다$\lrcorner$라고 말하고 다음과 같이 해명하고 있는데 그 요지는 다음과 같다.

• 전기의세계
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• v.46 no.12
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• pp.18-22
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• 1997

우리 학회에서는 선진국과의 기술협력 강화, 국제적 입지의 향상, 국내 연구의 활성화 등의 취지로 1994년부터 ISAP 국제학술회의의 국내 유치를 추진하였으며 노력을 경주한 결과 1995년 12월 ISAP 국제운영위원회(ISC:International Steering Committee)로부터 유치 확정 통보를 받았다. 1996년 1월에 본 학회 이사회에서는 ISP'97 국제 학술회의를 학회 창립 50주년 기념행사의 일환으로 치를 것을 결정하였고 1996년 2월 ISAP'96 대회기간중 열린 ISC 회의에서 원래 '97년 8월중으로 예정된 개최일자를 '97년 7월로의 변경을 신청하여 승인하였다. ISP'97 국제학술회의에서는 창립 50주년 기념 국제학술회의로서의 의의를 높이고 많은 회원들의 참여를 유도하기 위하여 대회 주제의 범위를 전력시스템 분야만이 아니고 발전소, 전기기기, 원자력 등을 포함한 일반 전기공학의 모든 분야에 있어서의 지능형시스템 신기술 응용으로 확대하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2021.11a
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• pp.36-38
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• 2021

스마트폰의 다양한 사진들은 현재 대부분 저장 일자를 기준으로 표시되기 때문에 특정 사진을 검색할 경우 많은 노력이 필요하다. 이를 해결하기 위하여 몇몇 앨범형 앱들이 개발되었지만 실제 사용자가 직접 사진을 선택해야 하는 문제점이 존재한다. 이를 해결하기 위하여 본 논문에서는 사진들의 특징을 이용하여 사진의 자동으로 분류가능한 앱의 개발에 대하여 설명한다. 개발된 앱은 위치 및 인물에 따라 현재 사진들을 자동으로 분류하고 폴더에 저장함으로써 보다 쉽게 사진을 관리 할 수 있다. 제안된 기능은 안드로이드 기반으로 개발되었고 각 기능이 정상적으로 동작함을 실험을 통하여 증명하였다.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.3
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• pp.213-218
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• 2014

Effects of elevated $CO_2$ on leaf phenology of Quercus acutissima were examined using open-top chambers, which had ambient and elevated $CO_2$ concentrations (ambient ${\times}1.4$, ambient ${\times}1.8$). To analyze the effect of chamber, non-treatment block was established near outside of the chambers. In 2013, budburst, leaf unfolding, coloring, and shedding were surveyed, and spring phenology was surveyed in 2014. Thermal sum (base temperature $+5^{\circ}C$) of each phenological event occurred was recorded. In addition, bud samples were collected and analyzed for carbohydrate contents in March 2014. Elevated $CO_2$ concentration advanced budburst and leaf unfolding, and delayed shedding in 2013. However, in 2014, the temperature of the spring season was high, and there was no significant effect of elevated $CO_2$ concentration on spring phenology. Carbohydrates content, such as starch, total non-structural carbohydrate and total soluble sugar, were significantly increased in response to elevated $CO_2$ concentration. It has been proposed that elevated $CO_2$ concentration could extend the growing season of temperate species with increased possibility of frost damage due to early bud opening and leaf unfolding. However, our analysis showed that the increased carbohydrate concentration in bud under elevated $CO_2$ would reduce the possibility of early spring frost damage by acting as cryoprotectant.

• Proceedings of the Korea Water Resources Association Conference
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• 1993.07a
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• pp.327-334
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• 1993

일유출량을 모의하는 수문모형이 많이 개발되었지만 그 이용에 있어서는 입력자료와 매개변수가 다양하고 매개변수의 산정에 경험을 필요로 하는 경우가 많기 때문에 수문실무자들이 사용하기에는 다소 어려운 점이 있다. 본 연구에는 최소의 입력자료(강우량, 증발량)와 매개변수로 일자연유량을 모의할 수 있는 집중형 확정론적 모형을 개발하였는데, 관측된 수문곡선으로부터 입력매개변수를 도출할 수 있으며 그 종류가 작기때문에 실무에서 쉽게 이용할 수 있도록 하였다. 개발된 모형의 기본 개념은 강우-유출에 질량불변의 법칙을 적용하고, 선형저수지와 유사한 다중 감수 과정에 따른 수문곡선에 근거한다. 제안된 수문곡선은 차단을 제외한 강우량에 기인한 유량의 시간분포를 나타내며 기저유출과 장래에 손실될 증발산량을 포함한다. 제안된 수문곡선은 2개의 상승부와 3개의 감수부로 구성되며 수문곡선의 우측부는 개방되어 있다. 수문곡선의 상승부에는 감수계수의 개념을 역으로 적용하였으며, 계산을 단순화 하기 위하여 각 상승부 및 감수부의 구간은 정수값만을 갖는다고 가정하였다. 개발된 모형을 한강유역의 인도교지점(1918-1974), 영산강유역의 나주지점(1906-1990)의 일유출량을 모의하기 위하여 적용하였다. 모형의 적용결과 모의 기간중에 매개변수의 조정없이 전 기간에 걸쳐서 양호한 장기간의 일유출량 모의 결과를 얻을 수 있었다.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.242-248
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• 2017

This study was conducted to develop a cylindrical paperpot manufacturing equipment which is capable of continuously producing paperpots with a constant size. The equipment consists of the soil supply part, the paper supply part, the pot manufacturing part, the paperpot cutting part and its process for manufacturing paperpot from the soil supply to the paperpot cutting is continuously performed. As a result of the performance test using this equipment, we suggest that the optimal moisture content and injection pressure to supply soil are 50%~60%, and 0.5 Mpa respectively. Moreover the appropriate temperature for adhesive strength is $150{\sim}160^{\circ}C$ taking into account the performance of device and adhesion time. Also, considering the cutting speed and safety, it is appropriate to adopt a straight blade having a clean plan at a minimum angle of $30^{\circ}$. In addition, the manufacturing capacity of the developed equipment was 3300 pots per hour.

• Research in Plant Disease
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• v.21 no.1
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• pp.27-31
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• 2015

In April 2014, Fusarium wilt was found on kohlrabi seedlings in Iksan, Korea. Symptoms included wilting of foliage, drying and withering of older leaves, and stunting of the plants. The infected plants eventually died during growth. Colonies on potato dextrose agar were pinkish white, and felted with cottony and aerial mycelium. Macroconidia were falcate to almost straight, thin walled and usually 3-septate. Microconidia were usually formed abundantly in false-heads on short monophialides on the hyphae and were hyaline, smooth, oval to ellipsoidal, aseptate or medianly 1-septate, very occasionally 2-septate, slightly constricted at the septa, $4-11{\times}2.5-5{\mu}m$. On the basis of the morphological characteristics and phylogenetic analyses of molecular markers (internal transcribed spacer rDNA and translation elongation factor $1{\alpha}$), the fungus was identified as Fusarium oxysporum. Pathogenicity of a representative isolate was proved by artificial inoculation, fulfilling Koch's postulates. To our knowledge, this is the first report on the occurrence of Fusarium oxysporum on kohlrabi in Korea.

• Research in Plant Disease
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• v.24 no.1
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• pp.75-80
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• 2018

From 2014 to 2016, Fusarium wilt disease was found on fassionfruit in Iksan and Jeju, Korea. Symptoms included wilting of foliage, drying and withering of leaves, and stunting of the plants. The infected plants eventually died during growth. Colonies on potato dextrose agar were pinkish white, and felted with cottony and aerial mycelia with 35 mm after one week. Macroconidia were falcate to almost straight, thin-walled and usually 2-3 septate. Microconidia were usually formed on monophialides of the hyphae and were hyaline, smooth, oval to ellipsoidal, aseptate or medianly 1-septate, very occasionally 2-septate, slightly constricted at the septa, $3-12{\times}2.5-6{\mu}m$. On the basis of the morphological characteristics and phylogenetic analyses of two molecular markers, internal transcribed spacer rDNA and translation elongation factor $1{\alpha}$, the fungus was identified as Fusarium oxysporum. Pathogenicity of a representative isolate was proved by artificial inoculation, fulfilling Koch's postulates. To our knowledge, this is the first report on the occurrence of F. oxysporum on fassionfruit in Korea.