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Classification of Pseudomonas solanacearum isolates from tobacco plants in Korea (우리나라 담배 세균성마름병균(입고병균 : Pseudomonas solanacearum)의 Race와 Biochemical Type)

  • Yi Young Keun;Kim Jeong Hwa;Kang Seo Kyu
    • Korean journal of applied entomology
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    • v.21 no.3 s.52
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    • pp.123-127
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    • 1982
  • Fourteen isolates of Pseudomonas solanarearum virulent to tobacco cultivars were selected among isolates obtained from tobacco plants shelving wilt symptoms throughout the country during $1980\~1981$. The fourteen isolates were classified into two races based on reactions in eggplant, tomato, red pepper, potato and tobacco, and also classified into biochemical type 1 and type 4 according to physiological characteristics.

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Design and Control of a Bidirectional Power Conversion System with 3-level T-type Inverter for Energy Storage Systems

  • Sung, Won-Yong;Ahn, Hyo Min;Oh, Chang-Yeol;Lee, Byoung Kuk
    • Journal of Electrical Engineering and Technology
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    • v.13 no.1
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    • pp.326-332
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    • 2018
  • In this paper, the design process and the control method of the power conversion system (PCS) that consists of a bidirectional DC-DC converter and a 3-level T-type inverter for an energy storage system is presented. Especially the design method of the output LCL filter for a 3-lvel T-type inverter without complex mathematical process are proposed. The validity of the control method and design process in this paper are verified through simulation and experimental analysis.

VISUALIZATION OF INTERNAL DEFECTS IN PLATE-TYPE NUCLEAR FUEL BY USING NONCONTACT OPTICAL INTERFEROMETRY

  • Park, Seung-Kyu;Park, Nak-Gyu;Baik, Sung-Hoon;Kang, Young-June
    • Nuclear Engineering and Technology
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    • v.45 no.3
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    • pp.361-366
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    • 2013
  • An imaging technique to visualize the internal defects in a plate-type nuclear fuel specimen was developed by using an active optical interferometer for a nondestructive quality inspection. A periodic thermal wave having a sinusoidal intensity pattern induced a periodical strain variation for the specimen. The varying strain image was acquired using an optical laser interferometer. The strain distribution over the internal defects will be distorted in an acquired strain image because a part of the thermal wave will be reflected from these defects during propagation. In this paper, internal defects were efficiently visualized by sequentially accumulating the extracted defect components. The experimental results confirmed that the developed visualization system can be a valuable tool to detect the internal defects in plate-type nuclear fuel.

Manufacturing Characteristics of Cement-Bonded Wood Composite Board as Sound Absorption Type-Noise Barrier

  • Suh, Jin-Suk;Kang, Eun-Chang;Park, Jong-Young
    • Journal of the Korean Wood Science and Technology
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    • v.32 no.6
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    • pp.50-56
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    • 2004
  • This study was conducted to investigate the performance of sound absorption type-noise barriers manufactured with a combination of wood particles used for particleboard, recycled waste newspaper, and cement. An average density of wood-combined cement board was in the range from 0.83 to 0.96 g/cm3, showing relatively low-density board. Regardless of types of cement bonded board or wooden board, the board with concave holes(凹)-formed surfaces showed greater sound absorption coefficient compared to those of flat surface boards. The board density was not related with those coefficients. Accordingly, it was concluded that concave or deep corrugated surface structure has played an important role in sound absorption for the application of sound absorption type-noise barrier.

NEW PROOFS OF SOME FIXED POINT THEOREMS FOR MAPPINGS SATISFYING REICH TYPE CONTRACTIONS IN MODULAR METRIC SPACES

  • Godwin Amechi Okeke;Daniel Francis;Jong Kyu Kim
    • Nonlinear Functional Analysis and Applications
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    • v.28 no.1
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    • pp.1-9
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    • 2023
  • Our aim in this paper is to give some new proofs to fixed point theorems due to Abdou [1] for mappings satisfying Reich type contractions in modular metric spaces. We removed the restriction that ω satisfies the ∆2-type condition imposed on the results of [1]. Furthermore, Lemma 2.6 of [1] which was crucial in the proofs of the results of [1] is not needed in the proofs of our results. Our method of proof is simpler and interesting.

Design of type 316L stainless steel 700 ℃ high-temperature piping

  • Hyeong-Yeon Lee;Hyeonil Kim;Jaehyuk Eoh
    • Nuclear Engineering and Technology
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    • v.55 no.10
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    • pp.3581-3590
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    • 2023
  • High-temperature design evaluations were conducted on Type 316L stainless steel piping for a 700 ℃ large-capacity thermal energy storage verification test loop (TESET) under construction at KAERI. The hot leg piping with sodium coolant at 700 ℃ connects the main components of the loop heater, hot storage tank, and air-to-sodium heat exchanger. Currently, the design rules of ASME B31.1 and RCC-MRx provide design procedures for high-temperature piping in the creep range for Type 316L stainless steel. However, the design material properties around 700 ℃ are not available in those rules. Therefore, a number of material tests, including creep tests at various temperatures, were conducted to determine the insufficient material properties and relevant design coefficients so that high-temperature design on the 700 ℃ piping may be possible. It was shown that Type 316L stainless steel can be used in a 700 ℃ high-temperature piping system of Generation IV reactor systems or a renewable energy systems, such as thermal energy storage systems, for a limited operation time.

Development of a Trawl Escapement Net using net material (망지를 이용한 트롤 탈출장치 개발)

  • Cho, Sam-Kwang;Shin, Jong-Keun;Cha, Bong-Jin;Yang, Yong-Su
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.44 no.3
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    • pp.165-173
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    • 2008
  • Sea experiment for this study was carried out to develop a Trawl Escapement Net(TEN) using net material to improve the survival rate of undersized fishes that escaped from trawls in the Korean southern sea in May and November, 2005. Three kinds of Trawl Escapement Net(TEN) were examined to increase the escapement rate for fishes escaped from the TEN, and total catches in the codend and cover-net were investigated. The main catch species in the experimental fishing trials using a V shape TEN(A type) in May were Korean pomfret(Pampus echinogaster), slimy(Leiognathus nuchalis), gizzard shad(Konosirus punctatus), white croaker(Pennahia argentata) and smelt(Sillago sihama). In the experimental fishing trials using a V shape TEN with a protector for undersized fishes(B type) and a panel shape TEN with a protector(C type) in November, the main catch species were horse mackerel(Trachurus japonicus), sea pike (Sphyraena japonica), large-head hairtail(Trichiurus lepturus), kammal thryssa(Thryssa kammalensis), white croaker(Pennahia argentata), butterfish(Psenopsis anomala) and red gurnard(Lepidotrigla microptera). Most of large-sized fish species like Korean pomfret and Spanish mackerel could not escape through the TEN in the B type and C type. Catches of horse mackerel were highest in the experimental fishing of November and escapement rates for most fish species including horse mackerel were higher in the C type compared with B type.

Structure and Succession of Zooplankton Community in Several Artificial Lakes in the Han River System (한강 수계 주요 댐호에서의 동물플랑크톤 군집 구조와 천이)

  • You, Kyung-A;Park, Hae-Kyung;Kong, Dong-Soo;Hwang, Soon-Jin
    • Journal of Korean Society on Water Environment
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    • v.26 no.5
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    • pp.850-859
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    • 2010
  • Structure and succession of zooplankton community studied by hydraulic and ecological characteristics targeting the five lakes in the Han river system from March to December 2008. Results separated by river-type lake and lake-type lake depending on the type of hydraulic, Paldang lake and Cheongpyeong lake were river-type lake, while Chungju lake, Hoengseong lake and Doam lake was lake-type lake. The Paldang lake was a eutrophic lake, zooplankton community density and species number were the most among the five lakes. Relative dominance of the rotifera was the largest and the yearly first dominant species was a small cladocera Bosmina longirostris. The Cheongpyeong lake was a mesotrophic-eutrophic lake, hydraulic characteristics and zooplankton community changes were similar the Paldang lake. Relative dominance of the cladocera was the largest and the yearly first dominant species was a small cladocera Bosmina longirostris. The Chungju lake was a oligotrophic-mesotrophic lake, zooplankton community density was the least among the five lakes. Relative dominance of the copepoda was the largest and the yearly first dominant species was a large cladocera Daphnia galeata. The Hoengseong lake was a oligotrophic-mesotrophic lake, relative dominance of the rotifera was the largest and the yearly first dominant species was a small cladocera Bosmina longirostris. The Doam lake was a mesotrophic-eutrophic lake, zooplankton community density showed dramatic difference at the investigation time. Relative dominance of the rotifera was the largest and the yearly first dominant species was the copepoda Nauplius.

Effect of bone quality and implant surgical technique on implant stability quotient (ISQ) value

  • Yoon, Hong-Gi;Heo, Seong-Joo;Koak, Jai-Young;Kim, Seong-Kyun;Lee, Su-Young
    • The Journal of Advanced Prosthodontics
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    • v.3 no.1
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    • pp.10-15
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    • 2011
  • PURPOSE. This study investigated the influence of bone quality and surgical technique on the implant stability quotient (ISQ) value. In addition, the influence of interfacial bone quality, directly surrounding the implant fixture, on the resonance frequency of the structure was also evaluated by the finite element analysis. MATERIALS AND METHODS. Two different types of bone (type 1 and type 2) were extracted and trimmed from pig rib bone. In each type of bone, the same implants were installed in three different ways: (1) Compaction, (2) Self-tapping, and (3) Tapping. The ISQ value was measured and analyzed to evaluate the influence of bone quality and surgical technique on the implant primary stability. For finite element analysis, a three dimensional implant fixture-bone structure was designed and the fundamental resonance frequency of the structure was measured with three different density of interfacial bone surrounding the implant fixture. RESULTS. In each group, the ISQ values were higher in type 1 bone than those in type 2 bone. Among three different insertion methods, the Tapping group showed the lowest ISQ value in both type 1 and type 2 bones. In both bone types, the Compaction groups showed slightly higher mean ISQ values than the Self-tapping groups, but the differences were not statistically significant. Increased interfacial bone density raised the resonance frequency value in the finite element analysis. CONCLUSION. Both bone quality and surgical technique have influence on the implant primary stability, and resonance frequency has a positive relation with the density of implant fixture-surrounding bone.

The Effects of Types of Envy and Self Construal Level on Indulgence (부러움의 유형과 자아해석의 고저수준에 따른 탐닉적 소비성향의 차이)

  • Choi, Nak-Hwan
    • The Journal of Industrial Distribution & Business
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    • v.9 no.5
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    • pp.73-81
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    • 2018
  • Purpose - When indulging in hedonic items is construed as wasteful and evokes anticipated regret or guilt, consumers are more likely to seek reasons to justify their indulgence. Justification requirement for spending on indulgences over necessities could lead to the places of their finding the ways that mitigate the anticipated regret and guilt. However the previous research focusing on consumers' own great effort leading to positive outcomes has not given much attention to other's outcomes induced from his or her little or no efforts, by which consumers could feel envy. The guilt associated with consumers' indulgence could vary according to envy type felt according to their evaluation about other's outcomes and their self construal level. Current research explored the envy type's effects on consumers' spending on hedonic products, and moderation effects of self construal level on the envy type's effects. Research design, data, and methodology - 2(envy type: benign versus malicious) × 2(self construal level: high versus low) between-subjects design was employed. Data for empirical analysis were from 173 undergraduate participants. ANOVA was used to verify hypotheses. Results - The tendency of choosing utilitarian product versus hedonic product was moderated by the envy type. The participants who felt benign envy were more likely to choose utilitarian product versus hedonic product than those who felt malicious envy were. And the tendency of benign envy-felt participants' choosing hedonic versus utilitarian product was more weakened to those with lower-level self construal than to those with higher-level self construal. However the tendency of malicious envy-felt participants' choosing hedonic versus utilitarian product was not moderated by the self construal level. Conclusions - This research could advance the theory related to indulgent hedonic consumption by exploring the effects of self construal level and envy type on hedonic indulgence. In view of the results from current study, marketers should make efforts of communicating and selling utilitarian products to persuade consumers with lower-level construal when they feel benign envy to others. And they should conduct marketing acts for hedonic products to persuade consumers when they feel malicious envy to others.