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Flora, life form characteristics, and plan for the promotion of biodiversity in South Korea＇s Globally Important Agricultural Heritage System, the traditional Gudeuljang irrigated rice terraces in Cheongsando

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Journal of Mountain Science 2017年第6期14卷 1212-1228页

作者： hong chul park Chaang Hveon OH Korea National park Research Institute Korea National Park Service Wonju-si Gangwon-do 26441 Korea Department of Biological and Environmental Science Dongguk University Goyang-si Ggeonggi-do 10326 Korea

The objectives of this study were to analyze the biodiversity of the Traditional Gudeuljang Irrigated Rice Terraces in Cheongsando, South Korea's representative GIAHS(Globally Important Agricultural Heritage System) site, with reference to position and land-use features, and to develop a plan to promote agricultural biodiversity in the region. We confirmed approximately 54,000 m2 of Gudeuljang paddy fields by an on-site survey. Of the Traditional Gudeuljang Irrigated Rice Terraces confirmed by onsite inspection, our survey showed that approximately 24,000 m2 are currently being used as paddy fields, approximately 15,000 m2 are being used as dry fields, and approximately 14,000 m2 are fallow. In terms of other non-agricultural land use, there was grassland, including graveyards; artificial arboreal land, such as orchards, rivers and wetlands, and man-made facilities, such as roads and residences. We also confirmed that the Traditional Gudeuljang Irrigated Rice Terraces had higher plant species diversity than conventional terraced rice paddies, and there was a difference in life form characteristics between the two types. Although the superficial topsoil structure is thesame for the Traditional Gudeuljang Irrigated Rice Terraces(TGIRTs) and conventional terraced rice paddies, it is thought that the differences in the subsurface structure of the TGIRTs contribute greatly to species and habitat diversity. However, the TGIRTs in Cheongsando are facing degeneration, due to damage and reduction in agricultural activity. The main cause is the reduction in the number of farming households due to an aging population in Cheongsando. In order to address this problem, we proposed a management plan, related to fallow paddy fields in South Korea, to initiate voluntary activities in the TGIRTs.

关键词： Globally Important Agricultural Heritage System Rice terrace Agricultural biodiversity Topsoil structure Gudeuljang

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Potential effects of future adoption of the REDD mechanism as a preventive measure against deforestation and forest degradation in North Korea

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Journal of Mountain Science 2016年第9期13卷 1645-1651页

作者： hong chul park Choong Hyeon OH Korea National park Research Institute Korea National Park Service Department of Biological and Environmental Science Dongguk University

This study assesses potential effects of adaption to climate change in the future as a carbon related value using a baseline and credit approach, considering the implementation of the Reducing Emissions from Deforestation and forest Degradation （REDD） mechanism. Basic data were obtained for implementing the REDD mechanism in the Democratic People＇s Republic of Korea （DPRK） for scientific decision-making to prevent deforestation and forest degradation. The potential effects according to the implementation of the REDD mechanism in the DPRK based on forest status data （the latest） are as follows. If the deforestation rate is reduced to a level below 6% through a 20-year REDD mechanism beginning in 2011, 0.01-11.64 C-tons of carbon credit per ha could be issued for DPRK. Converted into C02-tons per ha, this amounts to 0.03-42.68 C02-tons, which translates to a minimum of 226,000 CO2-tons and a maximum of 289,082,000 C02-tons overall for forests in DPRK. In terms of carbon price, this measures up to 1.1o million USD- 1.4 billion USD, considering that the REDD carbon price in voluntary carbon markets in 2010 was around 5 USD.

关键词： Climate change Global warming Baseline approach Carbon Credit

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科尔沁沙地丘间低地不同生活型物种格局与共存机制

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生态学杂志 2016年第1期35卷 111-117页

作者：贾美玉李雪华吴忠铉朴弘哲苗纯萍韩旭中国科学院沈阳应用生态研究所沈阳110016 中国科学院研究生院北京100049 韩国东国大学

植物种群格局与不同生活型之间物种共存的研究有助于理解物种的生态适应性。丘间低地是科尔沁沙地生态系统发育的一个关键阶段,在此生境中存在多种生活型的植物。采用样线法调查了科尔沁沙地丘间低地100个1 m×1 m样方,根据调查结果选... 详细信息

植物种群格局与不同生活型之间物种共存的研究有助于理解物种的生态适应性。丘间低地是科尔沁沙地生态系统发育的一个关键阶段,在此生境中存在多种生活型的植物。采用样线法调查了科尔沁沙地丘间低地100个1 m×1 m样方,根据调查结果选取了分属于4个科3个生活型的15种植物为对象进行格局和共存机制的研究。经格局指数以及Poisson分布的t检验和χ2检验表明:15个物种的种群分布均为聚集分布,但聚集强度差别很大,这可能由种子扩散、物种形态、植物发育时期以及土壤养分条件差异导致;聚集指数DI、CI、m*、GI之间呈极显著正相关关系,表明它们表征共同的生态学意义,相互之间可以替代;多年生草本这一生活型内的物种相互共存较多,多年生草本与其他两个生活型共存较少,这可能与相同生活型物种生态位重叠度大有关。Spearman秩相关和Pearson相关对物种对的检验结果均表明:部分豆科植物与其他科的多年生草本共存机会较大,这可能与豆科植物对改良土壤和减少病虫害有关。物种聚集分布以及不同生活型内几个物种对正相关显著是物种适应环境的结果,对结果显著的部分植物进一步研究可以为沙地植被恢复提供理论指导。

关键词：丘间低地聚集分布一年生草本多年生草本半灌木物种共存

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Stress analysis model of strip winding system with a sleeve for a coil of thin stainless steel

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Journal of Iron and Steel Research International 2017年第1期24卷 1-7页

作者： Yong-hui park Kyutae park Sung-yeun Won Wan-kee hong Hyun-chul park Graduate School of Engineering Masterships Pohang University of Science and Technology(POSTECH)Kyungbuk 790 784PohangRepublic of Korea Mechanical Engineering Pohang University of Science and Technology(POSTECH)Kyungbuk 790-784PohangRepublic of Korea Mechanical Facility Research Group Engineering Solution CenterPOSCOKyungbuk 790-360PohangRepublic of Korea

In a strip winding process,the sleeve is a hollow cylinder that is mounted between a strip coil and a mandrel to maintain uniform coil shape when the strip coil is very thin,but its deformation behavior has not been investigated ***,a finite element（FE）model was presented to calculate the stress distribution in a sleeve and strip coil when 1-3mm-thick stainless steel was wound around the *** FE model was developed by extending aprevious model by adding a sleeve between the mandrel and strip,and by modifying the boundary and interaction *** strip winding process was divided into an initial process and a steady-state *** the initial process,the minimum and maximum pressure required on the belt wrapper to maintain coil shape by self-friction of the strip was calculated by the FE model when the belt wrapper is ejected at the end of the initial *** the initial process,an analytical model of the steady-state process was established to calculate the stress distribution and was compared with the FE model to validate *** suggested analytical model took 11 sto give the same stress distribution that the FE model took 30 dto produce.

关键词： Strip winding system Belt wrapper Grooved joint Radial stress Hoop stress Von-Mises stress Interference fit

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UBVVI Surface Photometry of the Spiral Galaxy NGC 300 in the Sculptor Group

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Chinese Journal of Astronomy and Astrophysics 2004年第4期4卷 299-310页

作者： Sang chul Kim Hwankyung Sung hong Soo park Eon-Chang Sung Korea Astronomy Observatory Taejon 305-348Republic of KoreaDepartment of Astronomy and Space ScienceSejong University98 Gunja-dongGwangjin-guSeoul 143-747Republic of KoreaAstronomy ProgramSEESSeoul National UniversitySeoul 151-742Republic of KoreaKorea Astronomy ObservatoryTaejon 305-348Republic of Korea

We present UBVI surface photometry over a 20.5' × 20.5' area of the late-type spiral galaxy NGC 300. We have derived isophotal maps, surface brightness profiles, ellipticity profiles, position angle profiles, and color profiles. By merging our I-band measurements with those of Boker et al. based on Hubble Space Telescope observations, we have obtained combined I-band surface brightness profiles for the region 0.02' < r < 500' and have decomposed the profiles into three components: a nucleus, a bulge, and an exponential disk.

关键词： galaxies: spiral - galaxies: photometry - galaxies: individual(NGC 300) - galaxies: nuclei

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Effect of Sub-T_g Annealing on the Corrosion Resistance of the Cu–Zr Amorphous Alloys

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Acta Metallurgica Sinica(English Letters) 2018年第3期31卷 273-280页

作者： Sang-Soo Shin hong-Kyu Kim Jae-chul Lee Ik-Min park Department of Materials Science and Engineering Pusan National University Advanced Analysis Center Korea Institute of Science and Technology Department of Materials Science and Engineering Korea University

Despite the economy of material cost and excellent toughness of Cu-based amorphous alloys,especially CusoZrso,their poor corrosion resistance to a chloride medium limits their widespread *** this study,corrosion tests were performed on the CusoZrso amorphous alloy with different degrees of short-range order,which were prepared by annealing below the glass transition temperature（Tg）.It was found that the corrosion resistance of amorphous alloys is improved to a significant level when the alloys were heated below *** studies showed that thermally activated relaxation process of created disorder,which occurs during sub-Tg annealing,is responsible for the improvement in the corrosion *** dynamics simulations performed on the Cu-Zr amorphous alloys demonstrated that the relaxation process of the alloys is associated with the formation of energetically stable icosahedra and icosahedron-like *** study highlights the effects of sub-Tg annealing on the improvement in the corrosion resistance of the amorphous alloys from the viewpoint the relaxation process of the short-range orders.

关键词： Amorphous alloys Corrosion Annealing Molecular dynamics Electrochemical performance

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Analysis and optimization of nitrile butadiene rubber sealing mechanism of ball valve

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中国有色金属学会会刊：英文版 2009年第B9期19卷 220-224页

作者： Young-chul park Department of Mechanical Engineering Dong-A University

An approach for analyzing and optimizing sealing mechanism of ball valve made of nitrile butadiene rubber(NBR) with finite element method was presented. The Mooney-Rivlin hyperelastic material model was chosen to characterize NBR sealing, as it has been recommended in the similar applications. That is, NBR sealing was modeled as incompressible hyperelasticity, as well as the assumption of isotropic flow. The results illustrate the structural pressure and contact pressure on the contact surface, which shows that the NBR sealing mechanism is very suitable for sealing after dimension optimization.

关键词：橡胶密封丁腈橡胶尺寸优化机制球阀有限元方法材料模型各向同性

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Bloch theorem dictated wave chaos in microcavity crystals

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Light(Science & Applications) 2023年第6期12卷 994-1000页

作者： Chang-Hwan Yi Hee chul park Moon Jip park Center for Theoretical Physics of Complex Systems Institute for Basic Science(IBS)Daejeon 34126Republic of Korea Department of Physics Pukyong National UniversityBusan 48513Republic of Korea Department of Physics Hanyang UniversitySeoul 04763Republic of Korea

Universality class of wave chaos emerges in many areas of science,such as molecular dynamics,optics,and network *** this work,we generalize the wave chaos theory to cavity lattice systems by discovering the intrinsic coupling of the crystal momentum to the internal cavity *** cavity-momentum locking substitutes the role of the deformed boundary shape in the ordinary single microcavity problem,providing a new platform for the in situ study of microcavity light *** transmutation of wave chaos in periodic lattices leads to a phase space reconfiguration that induces a dynamical localization *** degenerate scar-mode spinors hybridize and non-trivially localize around regular islands in phase *** addition,we find that the momentum coupling becomes maximal at the Brillouin zone boundary,so the intercavity chaotic modes coupling and wave confinement are significantly *** work pioneers the study of intertwining wave chaos in periodic systems and provide useful applications in light dynamics control.

关键词： theory. chaos wave

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Strong interlayer coupling and stable topological flat bands in twisted bilayer photonic Moiré superlattices

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Light(Science & Applications) 2022年第10期11卷 2523-2529页

作者： Chang-Hwan Yi Hee chul park Moon Jip park Center for Theoretical Physics of Complex Systems Institute for Basic Science(IBS)Daejeon 34126Republic of Korea

The moiré superlattice of misaligned atomic bilayers paves the way for designing a new class of materials with wide *** this work,we propose a photonic analog of the moiré superlattice based on dielectric resonator *** sharp contrast to van der Waals materials with weak interlayer coupling,we realize the strong coupling regime in a moiré superlattice,characterized by cascades of robust flat bands at large ***,we find that these flat bands are characterized by a non-trivial band topology,the origin of which is the moiré pattern of the resonator *** physical manifestation of the flat band topology is a robust one-dimensional conducting channel on edge,protected by the reflection symmetry of the moiré *** explicitly breaking the underlying reflection symmetry on the boundary terminations,we show that the first-order topological edge modes naturally deform into higher-order topological corner *** work pioneers the physics of topological phases in the designable platform of photonic moiré superlattices beyond the weakly coupled regime.

关键词： topological bands coupling

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Effects of design parameters and tension on behavior of a coil using finite element analysis

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Journal of Iron and Steel Research International 2018年第9期25卷 883-891页

作者： Kyu-tae parkI Hyun-chul park Department of Mechanical Engineering Pohang Universityof Science and Technology Pohang Gyeongbuk 790-784Korea

During the thin strip coiling process, it is necessary to use a sleeve with a mandrel to prevent excessive deformation of the strip. Stress distribution in the sleeve and in the strip is an important factor that determines the quality of the coil. However, owing to the accumulation of high pressure, it is difficult to determine the stress distribution through experimentation. Thus, stress analysis of the strip coiling process was conducted. Finite element analysis was used to investigate the effects of the weight of the strip and the mandrel on the stress distribution and stress concentration near the starting point of the coil. The radial stress was predicted for a coil with a stacked thickness of 384 mm, which corresponds to a strip length of 1486 m, using the stress analysis model developed in a preceding research. A method was presented to reduce the weight and radial stress of a strip coil. It was found that the deformation of the sleeve can be reduced by decreasing the gap between the mandrel segments. The thickness of the sleeve can be reduced from 120 to 106 mm using the stress analysis results. Furthermore, coiling tension can be reduced by 44% compared to the existing value considering the interlayer slip of the strip coil.

关键词： Strip coiling process Structural analysis Finite element method Mandrel Coiling tension

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