생물기후를 이용한 위해우려종(양서류)의 국립공원 서식 가능성 예측

박민규(Minkyu Park) 국립공원연구원 2021 국립공원연구지 Vol.11 No.1

환경부는 외래생물의 유입을 사전 예방하고 효과적으로 관리하기 위해 위해우려종을 지정하고 관리 정책을 추진하고 있다. 이 연구는 위해우려종 중 생물기후에 민감한 양서류를 대상으로 종분포모형을 활용하여 현재 및 미래 기후의 국립공원 서식 가능성을 예측하였다. 연구 대상종은 6개 종이며, 현재 및 RCP4.5, RCP8.5 기후 조건의 서식 가능성을 7개 Case로 구분하였다. 예측 결과 위해우려종의 자생지 위도(latitude) 범위가 한반도의 위도 범위와 유사한 Japanese common toad, Japanese brown frog는 대부분이 국립공원에서 서식 가능할 것으로 예측되었고 Marsh frog, Pool frog, African clawed frog는 기후의 극한지수 차이로 국립공원의 서식 가능성이 낮았다. The Ministry of Environment has designated potential risk species to prevent and effectively manage the alien species. This study predicted the potential habitat possibilities of the Korea national park for amphibians sensitive to climate change, present and future climate and used species distribution models for prediction. There are six amphibians for predicting habitat potential, and seven cases are classified according to climate change scenarios (present, RCP 4.5, RCP 8.5). According to the prediction results, Japanese common toad and Japanese brown frog were predicted to be inhabitable in most national parks. The reason may be that the bio-climate was also similar, because their latitude of native distributions area were similar to that of the Korean Peninsula. On the other hand, Marsh frog, Pool frog and African clawed frog are less habitat possibilities, due to differences in the extreme bio-climate between the native distributions area and the Korean peninsula.

Effect of varying the density of Ag nanowire networks on their reliability during bending fatigue

Park, Minkyu,Kim, Wonsik,Hwang, Byungil,Han, Seung Min Elsevier 2019 Scripta materialia Vol.161 No.-

<P><B>Abstract</B></P> <P>The effect of varying the density of Ag nanowire networks on their reliability was explored during cyclic bending. The reliability of the Ag nanowire network was degraded as the density of nanowires decreased, which is in contrast to E-beam evaporated dense Cu thin films that showed enhanced reliability for thinner films. The cause for such a reverse trend is explained by a percolation mechanism considering that the failure in the Ag nanowire network occurs locally at the junctions that are randomly distributed as opposed to fatigue-induced channel crack formation in a Cu thin film.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

SeaHERO core technology and its research scope for a seawater reverse osmosis desalination system

Park, Minkyu,Lee, Yun Seok,Lee, Young Geun,Kim, Joon Ha Informa UK (Taylor Francis) 2010 Desalination and Water Treatment Vol.15 No.1

Consideration of documentary records in the Annals of the Choson Dynasty for the frequency analysis of rainfall in Seoul, Korea : Documentary records for the frequency analysis of rainfall

Park, Minkyu,Yoo, Chulsang,Jun, Changhyun Wiley (John WileySons) 2017 Meteorological applications Vol.24 No.1

<P>In this study, flood records in the Annals of the Choson Dynasty (1392-1910) were considered for the frequency analysis of rainfall in Seoul, Korea. The old Korean rain gauge (Chukwooki) data (1777-1907) were also used to evaluate major flood records in the Annals of the Choson Dynasty. The design rainfalls were estimated using the binomial censored data maximum likelihood estimator. The results can be summarized as follows. (1) The frequency analysis was done for 24 h rainfall amounts as this was assumed to represent the three different rainfall records well: the documentary records in the Annals of the Choson Dynasty, the Chukwooki data and the modern data. Also, given the possible uncertainty level of the classification results of the documentary records, only 19 catastrophic events (the highest level of flood) were considered in the frequency analysis. The threshold value was decided to be 388 mm by comparing the documentary records with the Chukwooki data. (2) The sensitivity analysis shows that the effects of the threshold value, the number of catastrophic records, and the accuracy level of the flood records in the Annals of the Choson Dynasty on the frequency analysis results are very limited. That is, the length of the flood records in the Annals of the Choson Dynasty was found to be long enough to overcome the possible uncertainty of the flood records. (3) The design rainfalls estimated by taking into account the flood records in the Annals of the Choson Dynasty were found to be very similar to those for the modern data. However, the confidence intervals estimated by considering all the records available were found to be just one third of those of the modern data.</P>

Fabrication of a Combustion-Reacted High-Performance ZnO Electron Transport Layer with Silver Nanowire Electrodes for Organic Solar Cells

Park, Minkyu,Lee, Sang-Hoon,Kim, Donghyuk,Kang, Juhoon,Lee, Jung-Yong,Han, Seung Min American Chemical Society 2018 ACS APPLIED MATERIALS & INTERFACES Vol.10 No.8

<P>Herein, a new methodology for solution processed ZnO fabrication on Ag nanowire network electrode via combustion reaction is reported, where the amount of heat the reaction temperature to avoid damaging the underlying Ag nanowires. The degree of participation of acetylacetones, which are volatile fuels in the combustion reaction, was found to vary with the reaction temperature, as revealed by thermogravimetric and compositional analyses. An optimized processing temperature of 180 degrees C was chosen to successfully fabricate a combustion-reacted ZnO and Ag nanowire hybrid electrode with a sheet resistance of 30 Omega/sq and transmittance of 87%. A combustion-reacted ZnO on Ag structure was demonstrated as an efficient transparent electrode and electron transport layer for the PTB7-Th-based polymer solar cells. The superior electrical conductivity of combustion-reacted ZnO, compared to that of conventional sol-gel ZnO, increased the external quantum efficiency over the entire absorption range, whereas a unique light scattering effect due to the presence of nanopores in the combustion-derived ZnO further enhanced the external quantum efficiency in the 450-550 nm wavelength range. A power conversion efficiency of 8.48% was demonstrated for the PTB7-Th-based polymer solar cell with the use of a combustion-reacted ZnO/Ag NW hybrid transparent electrode.</P>

Anomalous Hall effects without net magnetization

Minkyu Park,Guihyun Han,S. H. Rhim 한국자기학회 2020 한국자기학회 학술연구발표회 논문개요집 Vol.30 No.1

Semi-lumped Balun Transformer using Coupled LC Resonators

Park, Jongcheol,Yoon, Minkyu,Park, Jae Yeong The Korean Institute of Electrical Engineers 2015 Journal of Electrical Engineering & Technology Vol.10 No.3

This paper presents a semi-lumped balun transformer using conventional PCB process and its design theory and geometry for the maximally flat response and wide bandwidth using magnetically coupled LC resonators. The proposed balun is comprised of two pairs of coupled resonators which share one among three LC resonators. It provides an identical magnitude and phase difference of 180° between two balanced ports with DC isolation and an impedance transformation characteristic. Theoretical design and analysis were performed to optimize the inductance and capacitance values of proposed balun device for obtaining the wide bandwidth and maximally flat response in its pass-band. Three balun transformers with a center frequency of 500 MHz were demonstrated for proving the concept of design proposed. They were fabricated by using lumped chip capacitors and planar inductors embedded into a conventional 4-layered PCB substrate. They exhibited a maximum magnitude difference of 0.8 dB and phase difference within 2.4 degrees.

Evolution of the large genome in <i>Capsicum annuum</i> occurred through accumulation of single‐type long terminal repeat retrotransposons and their derivatives

Park, Minkyu,Park, Jongsun,Kim, Seungill,Kwon, Jin‐,Kyung,Park, Hye Mi,Bae, Ik Hyun,Yang, Tae‐,Jin,Lee, Yong‐,Hwan,Kang, Byoung‐,Cheorl,Choi, Doil Blackwell Publishing Ltd 2012 The Plant journal Vol.69 No.6

<P><B>Summary</B></P><P>Although plant genome sizes are extremely diverse, the mechanism underlying the expansion of huge genomes that did not experience whole‐genome duplication has not been elucidated. The pepper, <I>Capsicum annuum</I>, is an excellent model for studies of genome expansion due to its large genome size (2700 Mb) and the absence of whole genome duplication. As most of the pepper genome structure has been identified as constitutive heterochromatin, we investigated the evolution of this region in detail. Our findings show that the constitutive heterochromatin in pepper was actively expanded 20.0–7.5 million years ago through a massive accumulation of single‐type <I>Ty3/Gypsy</I>‐like elements that belong to the Del subgroup. Interestingly, derivatives of the Del elements, such as non‐autonomous long terminal repeat retrotransposons and long‐unit tandem repeats, played important roles in the expansion of constitutive heterochromatic regions. This expansion occurred not only in the existing heterochromatic regions but also into the euchromatic regions. Furthermore, our results revealed a repeat of unit length 18–24 kb. This repeat was found not only in the pepper genome but also in the other solanaceous species, such as potato and tomato. These results represent a characteristic mechanism for large genome evolution in plants.</P>

Ultracompact Intrinsic Micro Air-Cavity Fiber Mach–Zehnder Interferometer

Minkyu Park,Sejin Lee,Woosung Ha,Dae-Kyu Kim,Woojin Shin,Ik-Bu Sohn,Kyunghwan Oh IEEE 2009 IEEE photonics technology letters Vol.21 No.15

<P>A compact intrinsic fiber Mach-Zehnder interferometer (MZI) is proposed and experimentally demonstrated by incorporating a micro air-cavity ablated by femtosecond laser irradiation. A short cavity of length ~ 10 mum along the single-mode fiber core provided two optical paths: one propagating through the air and the other guided along the ring-shaped silica cladding. A spectral analysis confirmed MZI in a good agreement with experimental results. Temperature-dependent spectral shifts were measured and analyzed.</P>

Relationship between personal care products usage and triclosan exposure

Minkyu Park,Seyoung Kim,Yeji Kim,Do Jin Nam,Jae-Hong Ryoo,Sinye Lim 대한직업환경의학회 2019 대한직업환경의학회지 Vol.31 No.-

Background: We aimed to find the exposure level of triclosan (TCS), a known endocrine disruptor, related to the use of personal care products using a nationally representative data of the general population in Korea. Methods: This study included data of 6288 adults aged 19 years and older (2692 men, 3596 women), based on the Second Korean National Environmental Health Survey (KoNEHS 2012–2014). The data were divided according to gender. The frequency and proportion of each variable were determined by dividing participants into two groups based on the top 75th percentile concentration of urinary TCS (male: 1.096 μg/g creatinine, female: 1.329 μg/g creatinine). Odds ratios (ORs) were calculated using logistic regression analysis for the high TCS exposure and low TCS exposure groups. Results: Overall, the proportion of participants using personal care products was higher in women than in men. There was a significantly higher proportion of participants in the high TCS exposure group with younger age, higher education and income levels and with more frequent use of fragrance products, hair care products, body cleansers, cosmetics, and antimicrobial agents. In both men and women, ORs tended to increase with increased frequency of use of hair care products, body cleansers, and cosmetics before and after adjustment. Conclusions: Our findings demonstrate that as the frequency of use of personal care products increases, urine TCS concentration increases. Because TCS is a well-known endocrine disruptor, further studies are needed and explore other health effects with exposure to TCS in general population in Korea.