检索结果-南通市图书馆

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

全球国际收支失衡与新兴市场

国际经济评论 2006年第5期 45-48页

作者： yung chul park 樊纲 David Vines 韩国首尔大学全球商业和金融研究中心国民经济研究所牛津大学

十个亚洲经济体，包括中国、日本以及四个最新的工业化国家和地区——就是东亚的四个经济体，还有其他的东盟国家，他们的外汇储备合起来已经达到了2．6万亿（整理者注：这是2006年3月末数字）。在过去的几个月当中，我们可以看到：虽... 详细信息

十个亚洲经济体，包括中国、日本以及四个最新的工业化国家和地区——就是东亚的四个经济体，还有其他的东盟国家，他们的外汇储备合起来已经达到了2．6万亿（整理者注：这是2006年3月末数字）。在过去的几个月当中，我们可以看到：虽然外汇储备的增加量不像过去那么明显，但是我们仍然可以通过这样一个数字看到，中国和日本在外汇储备中占了66％，而那些新兴的工业化国家和地区占了28％，其他的东盟国家占了差不多7％。

关键词：国际收支失衡新兴市场亚洲经济体工业化国家全球外汇储备东盟国家中国

全球国际收支失衡的可持续性、调整时机与对策建议

在线全文

学校读者我要写书评

暂无评论

国际经济评论 2006年第5期 62-64页

作者： Jean Pisani-Ferry yung chul park Naoyuki Yoshino 唐旭布鲁塞尔欧洲和全球经济实验室韩国首尔大学日本庆应大学中国人民银行研究局

全球国际收支失衡是我们讨论的一个出发点，对此我们有着明显不同的观点。总的来说，我们没有考虑到美国国际收支失衡的可持续性。我们提到了有关解决全球国际收支失衡的一些问题和概念，比如美国的资产回报率可能比较高等问题；前面的... 详细信息

全球国际收支失衡是我们讨论的一个出发点，对此我们有着明显不同的观点。总的来说，我们没有考虑到美国国际收支失衡的可持续性。我们提到了有关解决全球国际收支失衡的一些问题和概念，比如美国的资产回报率可能比较高等问题；前面的讨论主要是考虑到亚洲的顺差，特别是中国的顺差；有时候政策制订者会对危机做出过度反应；余永定也提到中国实际上并不想拥有太多的外汇储备。

关键词：国际收支失衡可持续性全球资产回报率政策制订者过度反应外汇储备美国

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

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2009年第B09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

Bloch theorem dictated wave chaos in microcavity crystals

在线全文

学校读者我要写书评

暂无评论

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

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

Characteristics of fever and response to antipyretic therapy in military personnel with adenovirus-positive community acquired pneumonia

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Military Medical Research 2020年第3期7卷 324-334页

作者： Hongseok Yoo Jimi Oh chul park Division of Pulmonary and Critical Care Medicine Department of Internal MedicineSamsung Medical CenterSungkyunkwan University School of MedicineSeoul 06351South Korea Department of Anesthesiology and Pain Medicine Asan Medical CenterUniversity of Ulsan College of MedicineSeoul 05505South Korea Division of Pulmonary Medicine Department of Internal MedicineWonkwang University HospitalIksan 54538South Korea

Background:In 2014,an outbreak of adenoviral pneumonia occurred in the Korean military training ***,there are limited data on the characteristics of the fever and its response to antipyretic therapy in immunocompetent adults with adenovirus-positive community-acquired pneumonia(CAP).Methods:The medical records of the patients who were admitted to the Armed Forces Chuncheon Hospital for the treatment of CAP between January 2014 and December 2016 were retrospectively *** patients were divided into three groups,namely,the adenovirus-positive(Adv)group,the adenovirus-negative(Non-Adv)group and the unknown pathogen group,according to the results of a polymerase chain reaction(PCR)test and sputum culture used to measure adenovirus and other bacteria or viruses in respiratory *** evaluated and compared the demographics,clinicolaboratory findings and radiological findings upon admission between the two ***:Out of the 251 military personnel with CAP during the study periods,67 were classified into the Adv group,while 134 were classified into the Non-Adv group and 50 were classified into the unknown pathogen *** patients in the Adv group had a longer duration of fever after admission((3.2±1.6)d vs.(1.9±1.2)d vs.(2.2±1.5)d,P=0.018)and symptom onset((5.8±2.2)d vs.(3.9±2.5)d vs.(3.7±2.0)d,P=0.006)than patients in the Non-Adv and unknown pathogen groups,*** patients in the Adv group had a higher mean temperature at admission(37.8±0.3 vs.37.3±0.3 vs.37.3±0.3,P=0.005),and more patients were observed over 40 and 39 to 40(14.9%vs.2.2%vs.4.0%,35.8%vs.3.7%vs.6.0%,P<0.001)than those in the Non-Adv and unknown pathogen groups,*** Adv group more commonly had no response or exhibited adverse events after antipyretic treatment compared to the Non-Adv group(17.9%vs.1.5%,35.0%vs.4.3%,P<0.001,P=0.05,respectively).In addition,the time from admission to overall clinical stabilization was significantly longer in the patients

关键词： Adenovirus Fever Response to antipyretic treatment

Spectrum and Singular Integrals on a New Weighted Function Space

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2018年第11期34卷 1692-1702页

作者： Hee chul PAK Young Ja park Department of Mathematics Dankook University Dandae-ro 119 Dongnam-gu Cheonan-si Chungnam 31116 Republic of Korea Department of Mathematics Hoseo University Hoeo-ro 79 Asan-si Chungnam 31499 Republic of Korea

We introduce a new function space that is much finer than the classical Lebesgue spaces, and investigate the continuity and the discontinuity of the Calderon-Zygmund operators on the new weighted spaces. In order to identify the continuity of singular integrals, we prove an interpolation theorem on the new spaces and propose a concept of the spectrum of base functions.

关键词： Function spaces singular integrals interpolation Calderdn Zygmund operators Holder's inequality L log L

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

在线全文

学校读者我要写书评

暂无评论

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