Complete genome sequence of Bean pod mottle virus identified from common bean (Phaseolus vulgaris)

조연화,Hoseong Choi,Soo Yeon Choi,Sang-Min Kim,Yu Mi Choi,Bong-Choon Lee,Won Kyong Cho 한국미생물학회 2020 미생물학회지 Vol.56 No.4

Bean pod mottle virus (BPMV) in the genus Comovirus is a plant virus infecting common bean. We obtained genomes of two BPMV isolates referred as Tigerskin-A and Tigerskin-B consisting of two RNA segments from common bean plants displaying viral disease symptoms by RNA-sequencing. RNA1 encodes a single polyprotein containing five mature proteins while RNA2 encodes a single polyprotein containing a movement protein and two coat proteins. The two BPMV isolates showed high sequence similarity (99.65% to 99.70%) to two isolates, IA-Di1 and Iowa-Desmodium illinoense 1, from the Desmodium illinoense in USA belonging to a flowering plant in the bean family.

De novo genome assembly and single nucleotide variations for Soybean yellow common mosaic virus using soybean flower bud transcriptome data

조연화,Hoseong Choi,Sang-Min Kim,Bong Choon Lee,Won Kyong Cho 한국응용생명화학회 2020 Journal of Applied Biological Chemistry (J. Appl. Vol.63 No.3

The soybean (Glycine max L.), also known as the soya bean, is an economically important legume species. Pathogens are always major threats for soybean cultivation. Several pathogens negatively affect soybean production. The soybean is also known as a susceptible host to many viruses. Recently, we carried out systematic analyses to identify viruses infecting soybeans using soybean transcriptome data. Our screening results showed that only few soybean transcriptomes contained virus-associated sequences. In this study, we further carried out bioinformatics analyses using a soybean flower bud transcriptome for virus identification, genome assembly, and single nucleotide variations (SNVs). We assembled the genome of Soybean yellow common mosaic virus (SYCMV) isolate China and revealed two SNVs. Phylogenetic analyses using three viral proteins suggested that SYCMV isolate China is closely related to SYCMV isolates from South Korea. Furthermore, we found that replication and mutation of SYCMV is relatively low, which might be associated with flower bud tissue. The most interesting finding was that SYCMV was not detected in the cytoplasmic male sterility (CMS) line derived from the non-CMS line that was severely infected by SYCMV. In summary, in silico analyses identified SYCMV from the soybean flower bud transcriptome, and a nearly complete genome of SYCMV was successfully assembled. Our results suggest that the low level of virus replication and mutation for SYCMV might be associated with plant tissues. Moreover, we provide the first evidence that male sterility might be used to eliminate viruses in crop plants.

마이크로채널 형상에 따른 PCHE 열유동 수치해석

조연화(Yeon Hwa Cho),이규정(Kyu Jung Lee),문동주(Dong Ju Moon),김윤호(Yoon Ho Kim) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.5

새롭게 제안된 형상의 마이크로채널 PCHE는 기존의 상용 열교환기에 비해 고성능, 고효율의 특성을 보이며 열교환을 수행한다. 본 연구에서는 I, Wavy, Beehive, Surf, I-Wavy, I-Beehive, I-Surf의 형상을 갖는 다양한 마이크로채널을 모델링하였다. 질량유속 변화에 따른 다양한 마이크로채널 내 유체의 유동 특성, 열전달, 압력강하를 살펴보았고 그 결과는 마이크로채널의 열전달 능력을 향상시키는데 향상시키는데 이용된다. I 채널은 새롭게 적용된 채널 형상과의 성능비교를 위해 해석을 수행하였다. 다양한 레이놀즈수 변화 하에서 고온측과 저온측 유체는 대향류 형태로 열교환이 이루어지도록 하였다. 수치해석 결과 Surf 형상이 다른 형상들보다 열교환 성능이 우수함을 확인하였다. The microchannel PCHE(printed Circuit Heat Exchanger) of the newly proposed shapes out-performs other existing commercial heat exchangers while retaining greater performance-effectiveness and energy-efficiency. Various microchannels with the shapes of I, Wavy, Beehive, Surf, I-Wavy, I-Beehive and I-Surf are computationally modeled in this study. Flow characteristics, heat transfer and pressure drop in the microchannel are investigated under the various mass flow rate conditions. The results are utilized to enhance the heat transfer performance of the microchannels. The I microchannel case is chosen to be benchmark case, whose results are compared with those of newly proposed microchannels. The counterflow is arranged at various Reynolds numbers of both hot and cold fluids. It is found that the shapes of surf is better than the others from the point of heat performance.

마이크로채널 형상에 따른 PCHE 열유동 수치해석

조연화(Yeon Hwa Cho),이규정(Kyu Jung Lee),문동주(Dong Ju Moon),김윤호(Yoon Ho Kim) 대한기계학회 2011 大韓機械學會論文集B Vol.35 No.1

새롭게 제안된 형상의 마이크로채널 PCHE는 기존의 상용 열교환기에 비해 고성능, 고효율의 특성을 보이며 열교환을 수행한다. 본 연구에서는 I, Wavy, Beehive, Surf, I-Wavy, I-Beehive, I-Surf 의 형상을 갖는 다양한 마이크로채널을 모델링하였다. 질량유속 변화에 따른 다양한 마이크로채널 내 유체의 유동특성, 열전달, 압력강하를 살펴보았고 그 결과는 마이크로채널의 열전달 능력을 향상시키는데 이용된다. I 채널은 새롭게 적용된 채널 형상과의 성능비교를 위해 해석을 수행하였다. 다양한 레이놀즈수 변화 하에서 고온측과 저온측 유체는 대향류 형태로 열교환이 이루어지도록 하였다. 수치해석 결과 Surf 형상이 다른 형상들보다 열교환 성능이 우수함을 확인하였다. The performance of microchannel PCHE (Printed Circuit Heat Exchanger) is superior to that of other existing commercial heat exchangers. Further, it is also more efficient than other heat exchangers. Various microchannels, whose shapes are straight (I), Wavy, Beehive, Surf, I-Wavy, I-Beehive, or I-Surf, are computationally modeled in this study. The counter-flow arrangement is used, and the flow characteristics, heat transfer, and pressure drop in the microchannels under various mass flow rate conditions are investigated. The results for I microchannel is chosen as the benchmarks and is compared with those of newly proposed microchannels. It is found that the surf-shaped microchannel is most efficient in improving the overall performance of a PCHE.

원심압축기 임펠러 편심에 따른 성능특성에 대한 유동해석

조종재(Jongjae Cho),신봉근(Bong Gun Shin),이승훈(SeungHoon Lee),조연화(Yeonhwa Cho),김길영(Kilyoung Kim),류시양(ShiYang Ryu) 한국추진공학회 2015 한국추진공학회 학술대회논문집 Vol.2015 No.5

기어드 타입 산업용 원심압축기의 경우, 임펠러의 자중에 의한 쳐짐과 불 기어가 피니언 기어를 미는 힘에 의해 임펠러 편심이 발생한다. 이러한 편심은 임펠러의 동역학 및 성능 특성 변화를 일으킨다. 이 편심에 의한 동특성 현상은 고압 압축기에서 주로 발생한다. 특히, 이 동역학적 불안정성은 임펠러나 축 베어링 파손을 일으킬 수 있다. 임펠러의 파손은 다른 요소부품들의 연쇄적인 손상을 초래하며, 이로 인한 갑작스런 정지 및 상당한 시간과 경제적인 손실을 야기할 수 있다. 따라서 이러한 편심에 의한 임펠러 및 베어링 파손을 방지하기 위해서는 편심에 따른 동역학 및 성능특성 변화에 대한 분석이 필요하다. 따라서 본 연구에서는 압축기 편심에 따른 임펠러에 작용하는 유동 가진력을 전산해석을 통하여 예측하였다. 또한 도출된 결과를 바탕으로 편심량에 따른 동역학적 불안정성과 성능특성을 비교·분석하였다. For an commercial integrally geared centrifugal compressor, the weight of impeller and the pressing force of a bull gear to pinion gear are eccentric to an impeller. The eccentric causes the dynamic and performance characteristics of a compressor. Dynamic instability caused by the eccentricity is mainly generated in the high-pressure compressor. In particular, this instability can cause damage to the impeller and shaft bearing. Damage of the impeller results in damage and failure of other component parts of a compressor, which resulting in sudden stop and in significant time and economic loss. Therefore, analysis of the change in dynamic and performance characteristics of the offset is required in order to prevent the impeller and bearing damage due to such eccentricity. Therefor, in this study, Exciting forces acting on the impeller due to instable flow according to the eccentric were predicted by computational analysis. In addition, comparing the dynamic instability and performance characteristics accoring to eccentricity were compared and analyzed by the numerical results.

원심압축기 쉬라우드 임펠러 형상에 따른 성능특성 파악을 위한 유동해석

조종재(Jongjae Cho),조연화(YeonHwa Cho),이승훈(SeungHoon Lee),신봉근(Bong Gun Shin),임강수(KangSoo Im),류시양(Shiyang Ryu) 한국추진공학회 2015 한국추진공학회 학술대회논문집 Vol.2015 No.5

원심압축기 운전 중에 발생하는 고주기 피로균열이나 공진 등은 임펠러 파손의 주된 원인이다. 이러한 파손을 회피하기 위해 공진영역 운전에서도 견딜 수 있는 충분한 강도의 임펠러를 설계하거나 공진이 발생하지 않도록 임펠러를 튜닝 한다. 하지만 이러한 방법을 통해 임펠러 파손은 회피할 수 있으나, 임펠러 내부 유동 및 성능특성 변화를 야기하게 된다. 따라서 임펠러 파손을 방지하고, 원심압축기의 성능지표를 만족하기 위해서는 유동 및 성능특성 변화에 대한 분석이 필요하다. 본 연구에서는 임펠러 두께를 증가시킨 모델과 임펠러 유로 출구부 쉬라우드면을 튜닝한 모델(스켈럽)에 대한 유동 및 성능특성을 파악하기 위해 전산해석을 수행하였으며, 도출된 결과를 바탕으로 각각의 유동 및 성능특성을 비교·분석하였다. The high-cycle fatigue cracking and resonance generated during an operation of a centrifugal are a main cause of impller damage. In order to prevent the damage, an engineer designs or modifies the impeller having sufficient strength to withstand the operating condition. The avoidance design will cause the change of flow condition within the impeller internal cannel and that of performance characteristics. Not only to prevent this damage but to satisfy the compressor perforamnce, the study on the flow and performanace characterisitcs for avoidance design is required. In this study, we performed a computational analysis to identify the flow and performance characteristics for the impeller shape by apply scallop and by increasing thickness of blade. Based on these results, flow and performance characteristics was analyzed.

Complete genome sequence of soybean dwarf virus infecting soybean (Glycine max L.)

Yeonhwa Jo(조연화),Hoseong Choi(최호성),Bong Choon Lee(이봉춘),Jin-Sung Hong(홍진성),Won Kyong Cho(조원경) 한국미생물학회 2022 미생물학회지 Vol.58 No.2

We found a soybean plant displaying severe viral disease symptoms, such as stunting, rugosity, and yellowing. To reveal the viral agent, we extracted total RNA from the leaf sample and prepared a ribosome-deleted library followed by RNAsequencing. Raw data were de novo assembled, and the assembled contigs were used in a BLASTX search against a viral protein database. We identified four contigs associated with Soybean dwarf virus (SbDV) belonging to the genus Luteovirus in the family Luteoviridae. We obtained the complete genome of SbDV isolate HS with 5,686 nucleotides (nt), encoding five open reading frames (ORFs). The phylogenetic analysis showed that SbDV isolate HS belongs to Group A containing isolates from the USA and the Czech Republic. Here, we report the complete genome sequence of SbDV isolate HS infecting soybean in Korea obtained by RNA-sequencing.

이방성 희토류 본드자석용 유기 바인더에 관한 연구

허정섭(Jeong-Sub Heo),조연화(Yeon-Hwa Cho),남성철(Sung-Cheol Nam),김지경(Ji-Kyeong Kim),이정구(Jung-Goo Lee),유지훈(Ji-Hoon Yu) 한국자기학회 2014 韓國磁氣學會誌 Vol.24 No.3

Anisotropic bonded magnet is composed of magnetic powder and organic binder. organic binder in bonded magnet, serves to orientation of the powder. organic binder is composed of polymer resin, lubricant, hardener and coupling agent, etc. in this study, selection of the various components to producing an organic binder and by adjusting the composition ratio and concentrate, apply to bonded magnet for producing an organic binder that suitable for magnetic powder. so evaluation of magnetic properties and mechanical properties, the organic binder ratio and component was confirmed to suitable for bonded magnet.

메탄계 가스의 Two-Phase Flow 현상에 따른 가스 익스팬더 성능 및 유동 특성 분석

신봉근(Bong Gun Shin),조연화(Yeonhwa Cho),임찬선(Chansun Lim) 대한기계학회 2018 대한기계학회 춘추학술대회 Vol.2018 No.12

In recent, the use of expander at a re-liquefaction system installed at LNG Ships is continuously increasing in order to improve the system performance. Expander used at the reliquefaction system can drop the temperature of the working fluid at the system exit to a lower level than JT valve and can reduce the power consumption of the system by using the energy generated during expansion process. The performance of the re-liquefaction system improves as the expander expansion ratio increases, which results in a two phase flow of working gas inside the expander. This working gas two phase flow reduces the expander’s aerodynamic performance and deteriorates the structure / dynamic characteristics. Therefore, it is very important to analyze the influence of the two phase flow on flow and performance characteristics of the expander. However, it is very difficult to investigate the effect by using previous the numerical methodologies due to complicated numerical models and high computation costs. In this study, the influence of the two phase flow on the flow and performance characteristics of expander using methane-based mixed gas as working gas were analyzed. Next, the new numerical methodology was suggested in order to reduce the computational cost and to improve the accuracy.

마이크로채널 메탄 수증기 개질 반응기의 열 및 물질 전달 특성에 관한 수치해석 연구

전승원(Seung Won Jeon),이규정(Kyu Jung Lee),조연화(Yeon Hwa Cho),문동주(Dong Ju Moon) 대한기계학회 2012 大韓機械學會論文集B Vol.36 No.9

마이크로채널 메탄 수증기 개질 반응기의 열 및 물질 전달 특성을 이해하기 위한 수치해석 연구를 수행하였다. Rh-촉매의 메탄 수증기 개질 반응과 Pt-촉매의 메탄 연소 반응을 함께 모델링하였다. 화학 반응의 반응 속도를 해석 모델에 적용하였다. 접촉시간, 평행류·대향류 등 유동 패턴, 채널 크기 등이 개질 성능과 온도 분포에 미치는 영향을 관찰하였다. 평행류와 대향류는 서로 반대되는 온도 분포를 갖게 되고, 그로 인해 서로 다른 반응 속도와 화학종 몰분율을 나타낸다. 접촉시간이 짧아지고 채널 크기가 증가할수록 촉매층과 혼합물 유동 사이의 물질 전달이 제한되어 개질 성능은 감소하게 된다. A numerical study of a microchannel steam methane reforming reactor has been performed to understand the characteristics of heat and mass transfer. The integration of Rh-catalyzed steam methane reforming and Pt-catalyzed methane combustion has been simulated. The reaction rates for chemical reactions have been incorporated into the simulation. This study investigated the effect of contact time, flow pattern (parallel or counter), and channel size on the reforming performance and temperature distribution. The parallel and counter flow have opposite temperature distribution, and they show a different type of reaction rate and species mole fraction. As the contact time decreases and channel size increases, mass transfer between the catalyst layer and the flow is limited, and the reforming performance is decreased.