• 한국정보기술응용학회:학술대회논문집
• /
• 한국정보기술응용학회 2007년도 추계 국제학술대회
• /
• pp.141-141
• /
• 2007

• 대한수학회보
• /
• 제53권5호
• /
• pp.1471-1481
• /
• 2016

We characterize reducing subspaces of weighted shifts with operator weights as wandering invariant subspaces of the shifts with additional structures. We show how some earlier results on reducing subspaces of powers of weighted shifts with scalar weights on the unit disk and the polydisk can be fitted into our general framework.

• Journal of the Korean Statistical Society
• /
• 제32권3호
• /
• pp.213-224
• /
• 2003

We give an overview of results which have appeared or will appear elsewhere demonstrating that by suitably modifying the bootstrap principle, its applicability can be greatly enhanced. Although we state our results for the iid case, extensions are, at least heuristically, easy.

• 한국자기학회:학술대회 개요집
• /
• 한국자기학회 2016년도 임시총회 및 하계학술연구발표회
• /
• pp.101-101
• /
• 2016

• 통상정보연구
• /
• 제18권2호
• /
• pp.85-103
• /
• 2016

본 연구에서는 금융위기를 전후하여 미국내 한인의 집거지역인 캘리포니아지역 한인경제의 변화와 한인은행에 대한 연구를 하였다. 미통계청의 Census자료를 이용해 한인경제에 대해 분석하고, 연방예금보험공사(FDIC: Federal Deposit Insurance Corporation)의 자료를 이용해 LA지역 한인은행의 현황(자산, 고용, 예금, 부채 등)에 대해 분석하였다. 그리고 한인은행 관계자와의 심층인터뷰를 통해 이들 금융기관의 현황과 문제점을 살펴보고, 이를 해결하기 위한 방안을 제시하였다. 통계자료로 살펴본 결과 재미한인들의 미국내 경제적 위상은 크게 향상된 것으로 나타났다. 또한 금융위기를 전후하여 도태되지 않은 한인금융기관은 미국내 주류은행들에 뒤지지 않는 규모의 은행으로 양적 팽창을 해왔음을 볼 수 있으며, 은행들의 체질도 상당부분 개선되고 있다. 또한 은행들의 경영성과도 지속적으로 개선되고 있는 것으로 나타났다.

• Smart Structures and Systems
• /
• 제5권4호
• /
• pp.329-344
• /
• 2009

Ultrasonic chaotic excitations combined with sensor prediction algorithms have shown the ability to identify incipient damage (loss of preload) in a bolted joint. In this study we examine a physical experiment on a single-bolt aluminum lap joint as well as a three-dimensional physics-based simulation designed to model the behavior of guided ultrasonic waves through a similarly configured joint. A multiple bolt frame structure is also experimentally examined. In the physical experiment each signal is imparted to the structure through a macro-fiber composite (MFC) patch on one side of the lap joint and sensed using an equivalent MFC patch on the opposite side of the joint. The model applies the waveform via direct nodal displacement and 'senses' the resulting displacement using an average of the nodal strain over an area equivalent to the MFC patch. A novel statistical classification feature is developed from information theory concepts of cross-prediction and interdependence. This damage detection algorithm is used to evaluate multiple damage levels and locations.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
• /
• pp.63-67
• /
• 2002

The induced chemical and salt solution in water or admixture are originated to the corrosion process of the steeo rebar. These liquids penetrate into concrete as the accompanied by the chemical reaction and cause to attack the steel rebar in concrete. Concrete surfaces which it exposed to deicing, water and sea water is allowed to enter the chlorides in the structures. To prevent from the source of corrosion and deterioration Is subjected to put an end to corrode or reduce to contaminate on the steel rebar. As this reason the MCI 2022 products are applied to the surface of concrete and steel rebar. The concrete samples were made of to the kind of four, i.e. RF, MR, MS, and MM. Corrosion inhibitor is applied to coat on the surface of concrete after it had been cured for 28days. Specimen were immersed in a 3.5％ sodium chloride solution. Concrete specimen were tested to determine the changes of the resistance polarization, Rp, over a 22 weeks period. MCI 2022 is significantly shown the corrosion inhibition of steel rebar in 3.5% NaCl solution. In the each different concrete sample, MS and MM is seemed to be better than others. The results are proofed that MCI 2022 is promised to maintain the inhibition of corrosion with high resistance polarization of the steel rebar in concrete.

• ALGAE
• /
• 제35권3호
• /
• pp.237-252
• /
• 2020

Temperate rocky reefs dominated by the giant kelp, Macrocystis pyrifera, support diverse assemblages of benthic macroalgae that provide a suite of ecosystem services, including high rates of primary production in aquatic ecosystems. These forests and the benthic macroalgae that inhabit them are facing both short-term losses and long-term declines throughout much of their range in the eastern Pacific Ocean. Here, we quantified patterns of benthic macroalgal biomass and irradiance on rocky reefs that had intact kelp forests and nearby reefs where the benthic macroalgae had been lost due to deforestation at three sites along the California, USA and Baja California, MEX coasts during the springs and summers of 2017 and 2018. We then modeled how the loss of macroalgae from these reefs impacted net benthic productivity using species-specific, mass-dependent rates of photosynthesis and respiration that we measured in the laboratory. Our results show that the macroalgal assemblages at these sites were dominated by a few species of stipitate kelps and fleshy red algae whose relative abundances were spatially and temporally variable, and which exhibited variable rates of photosynthesis and respiration. Together, our model estimates that the dominant macroalgae on these reefs contribute 15 to 4,300 mg C m^-2 d^-1 to net benthic primary production, and that this is driven primarily by a few dominant taxa that have large biomasses and high rates of photosynthesis and / or respiration. Consequently, we propose that the loss of these macroalgae results in the loss of an important contribution to primary production and overall ecosystem function.

• Nutritional Sciences
• /
• 제7권3호
• /
• pp.158-164
• /
• 2004

This study was conducted to define dietary patterns and to evaluate the effects of socioeconomic, acculturation and lifestyle factors on dietary patterns among 2,746 Korean- Americans in California. It was a cross-sectional telephone survey based on a representative sampling of individuals with a Korean surname using residential phone listings. It was conducted using a food frequency questionnaire that covered 20 food items, socioeconomic variables such as age, gender, income, education and acculturation, and lifestyle factors such as body weight, alcohol consumption, smoking, exercise and consumption of fast food. Four dietary patterns were identified: American Foods (AF), American Breakfast (AB), Korean Foods (KF) and Vegetables (Ⅴ). AF was associated with younger men, acculturation and fast food consumption. AB was associated with women, higher education, current smoking and fast food consumption. KF was associated with acculturation and lower socioeconomic status. Ⅴ was associated with lifestyle factors such as smoking, exercising and fast food consumption. The results of the study showed that socioeconomic and lifestyle factors influenced the dietary patterns of Korean- Americans. This should be considered when dietary interventions are designed for Korean-Americans to improve their health status.

• Earthquakes and Structures
• /
• 제18권3호
• /
• pp.275-284
• /
• 2020

The scope of this study is the comparison between experimental results of tests performed on a base isolated building using helical wire rope isolators (WRs), and results of Nonlinear Response History Analyses (NRHAs) performed using SAP 2000, a commercial software for structural analysis. In the first stage of this research, WRs have been tested under shear deformation beyond their linear range of deformation, and analytical models have been derived to describe the nonlinear response of the bearings under different directions of loading. On the following stage, shaking table tests have been carried out on a 1/3 scale steel model isolated at the base by means of curved surface sliders (CSS) and WRs. The response of the structure under ground motion excitation has been compared to that obtained using numerical analyses in SAP 2000. The feasibility of modelling the nonlinear behavior of the tested isolation layer using multilinear link elements embedded in SAP 2000 is discussed in this paper, together with the advantages of using WRs as supplemental devices for CSSs base isolated structures.