• Geomechanics and Engineering
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• 제2권4호
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• pp.281-302
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• 2010

An extended model for the response of a rigid footing on a reinforced foundation bed on super soft soil is proposed by incorporating the rough membrane element into the granular bed. The super soft soil, the granular bed and the reinforcement are modeled as non-linear Winkler springs, non-linear Pasternak layer and rough membrane respectively. The hyperbolic stress-displacement response of the super soft soil and the hyperbolic shear stress-shear strain response of the granular fill are considered. The finite deformation theory is used since large settlements are expected to develop due to deformation of the super-soft soil. Parametric studies quantify the effect of each parameter on the stress-settlement response of the reinforced foundation bed, the settlement and tension profiles.

• 소성∙가공
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• 제8권3호
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• pp.309-309
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• 1999

Effects of rare earth metals addition and aging treatment on corrosion resistance and mechanical properties of super duplex stainless steels were investigated using optical/SEM/TEM metallographic examination, an X-ray diffraction test, a potentiodynamic anodic polarization test and a tensile test. The performance of the experimental alloy with 0.32% REM addition was compared with commercial super duplex stainless steel such as SAF 2507 when they were exposed to solution annealing heat treatment and aging treatment. The corrosion resistance in CF environments and mechanical properties of the experimental alloy were found superior to those of the commercial duplex stainless steel. The REM with larger atomic radii than those of Cr, Mo and W may fill vacancies inside the matrix and around the grain boundaries, retarding formation of harmful intermetallic σ and χ phases. In addition, fine REM oxides/oxy-sulfides (1-3㎛) seemed to enhance the retardation effects. With REM additions, strength and ductility increased due to the phase and grain refinement caused by fine REM oxides and oxy-sulfides.

• Bulletin of the Korean Chemical Society
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• 제34권3호
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• pp.927-930
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• 2013

We developed an electroplating process of cobalt nanowires of which line-widths were between 70 and 200 nm. The plating electrolyte was made of $CoSO_4$ and an organic additive, dimethyldithiocarbamic acid ester sodium salt (DAESA). DAESA in plating electrolytes had an accelerating effect and reduced the surface roughness of plated cobalt thin films. We obtained void-free cobalt nanowires when the plating current density was 6.25 mA/$cm^2$ and DAESA concentration was 1 mL/L.

• 한국해양공학회지
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• 제19권6호통권67호
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• pp.16-21
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• 2005

In the design of super tankers or LNG carriers, which transport a large amount of liquid in the cargo tanks, the structural d11mage due to liquid sloshing is an important problem. The impact pressure from sloshing is most violent when the liquid motion of a partially filled tank is in resonance with the motion of a ship. In this study, the sloshing natural periods of a baffled tank, often installed to reduce liquid motion, is analyzed. A variational method is adopted to estimate the sloshing natural periods for a prismatic cargo tank with baffles of arbitrary filling depth of liquid; the results are compared with Lloyd's Register regulations on sloshing periods. In this study, using an effective liquid-fill-depth concept, sloshing periods for a baffled tank can be expressed by the same form as rectangular prismatic tanks without baffles. In contrast to Lloyd's Register regulations, which can be applicable only to cargo tanks with constant baffle size and distribution, the present results can be applicable to cases of variable baffle size and distribution.

• Journal of Ecology and Environment
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• 제47권4호
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• pp.228-240
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• 2023

Growing complexity in ecosystem structure and functions, under impacts of climate and land-use changes, requires interdisciplinary understandings of processes and the whole-system, and accurate estimates of the changing functions. In the last three decades, observation networks for biodiversity, ecosystems, and ecosystem functions under climate change, have been developed by interested scientists, research institutions and universities. In this paper we will review (1) the development and on-going activities of those observation networks, (2) some outcomes from forest carbon cycle studies at our super-site "Takayama site" in Japan, and (3) a few ideas how we connect in-situ and satellite observations as well as fill observation gaps in the Asia-Oceania region. There have been many intensive research and networking efforts to promote investigations for ecosystem change and functions (e.g., Long-Term Ecological Research Network), measurements of greenhouse gas, heat, and water fluxes (flux network), and biodiversity from genetic to ecosystem level (Biodiversity Observation Network). Combining those in-situ field research data with modeling analysis and satellite remote sensing allows the research communities to up-scale spatially from local to global, and temporally from the past to future. These observation networks oftern use different methodologies and target different scientific disciplines. However growing needs for comprehensive observations to understand the response of biodiversity and ecosystem functions to climate and societal changes at local, national, regional, and global scales are providing opportunities and expectations to network these networks. Among the challenges to produce and share integrated knowledge on climate, ecosystem functions and biodiversity, filling scale-gaps in space and time among the phenomena is crucial. To showcase such efforts, interdisciplinary research at 'Takayama super-site' was reviewed by focusing on studies on forest carbon cycle and phenology. A key approach to respond to multidisciplinary questions is to integrate in-situ field research, ecosystem modeling, and satellite remote sensing by developing cross-scale methodologies at long-term observation field sites called "super-sites". The research approach at 'Takayama site' in Japan showcases this response to the needs of multidisciplinary questions and further development of terrestrial ecosystem research to address environmental change issues from local to national, regional and global scales.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.757-762
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• 2001

CFT concrete has high flowing, high strength and resistance to material separation to use skyscraper structure. It is considered that concrete could fill the lower part of Diaphragm up. This kinds of CFT concrete hardly apply to building below 20 stories. Using the common use strength concrete to building below 20 stories brings to reduce construction cost. This concrete is needed that valid fluidity and packing ability with unit cement content as common use strength concrete. Offering a fundamental data and proportioning in CFT concrete of below 20 stories, it is executed basic property test, analysis of proportioning and mock up test.

• 한국실내디자인학회논문집
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• 제34호
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• pp.157-164
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• 2002

Online business these days prone to approach their costumers with improved module and various interface via Internet. This is more than just an act of providing enhancement, but a mean of finding out the customer's demand by enlarging their selection. This, however, is related to the bits per second of supplemental service network.For example, supplemental services that were not possible in the 56K modem era are now possible due to the information super highway network. To grope for new means of approaching, the best way will be by developing media that will collect customer's demands. Until now, customer's demands were evaluated by miniatures of apartment building, model houses or rendered images produced by 3D graphic softwares and pictures. Analyses were not available until evaluation were produced.Nowadays, utilizing the advanced Internet interface tools and various new media, customers are sought before the construction thus various studies to full fill the customer's demands are in process. This study is on development of a virtual module utilizing activated web environment. Analysis modules repeating the changes in customers are expected to deliver us a new trend.

• Journal of Astronomy and Space Sciences
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• 제33권3호
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• pp.185-196
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• 2016

New multiband BVRI light curves of NSVS 1461538 were obtained as a byproduct during the photometric observations of our program star PV Cas for three years from 2011 to 2013. The light curves indicate characteristics of a typical W-subtype W UMa eclipsing system, displaying a flat bottom at primary eclipse and the O'Connell effect, rather than those of an Algol/b Lyrae eclipsing variable classified by the northern sky variability survey (NSVS). A total of 35 times of minimum lights were determined from our observations (20 timings) and the SuperWASP measurements (15 ones). A period study with all the timings shows that the orbital period may vary in a sinusoidal manner with a period of about 5.6 yr and a small semi-amplitude of about 0.008 day. The cyclical period variation can be interpreted as a light-time effect due to a tertiary body with a minimum mass of 0.71 M_⊙. Simultaneous analysis of the multiband light curves using the 2003 version of the Wilson-Devinney binary model shows that NSVS 1461538 is a genuine W-subtype W UMa contact binary with the hotter primary component being less massive and the system shows a low mass ratio of q(m_c/m_h)=3.51, a high orbital inclination of 88.7°, a moderate fill-out factor of 30 %, and a temperature difference of ΔT=412 K. The O'Connell effect can be similarly explained by cool spots on either the hotter primary star or the cool secondary star. A small third-light corresponding to about 5 % and 2 % of the total systemic light in the B and V bandpasses, respectively, supports the third-body hypothesis proposed by the period study. Preliminary absolute dimensions of the system were derived and used to look into its evolutionary status with other W UMa binaries in the mass-radius and mass-luminosity diagrams. A possible evolution scenario of the system was also discussed in the context of the mass vs mass ratio diagram.

• 한국지반환경공학회 논문집
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• 제12권12호
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• pp.63-70
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• 2011

EPS지오폼은 다양한 강도, 밀도, 그리고 크기로 생산되는 일종의 화학합성물이다. EPS지오폼에 관한 근래의 발전으로 인해서, 그것의 사용은 급격하게 늘어나고있다. 이것은 초경량 재료로서 단위중량이 약 $0.16{\sim}0.47kN/m^3$ 인데, 이것은 채움재의 용도로 가장 대표적인 흙의 단위중량 $6.3{\sim}15.7kN/m^3$와 동일한 내구성을 가진다. 이런 장점에도 불구하고, EPS지오폼에 대한 회복탄성계수 표준측정방법은 보고된 바가 없는 실정이다. 본 연구의 주된 목적은 연성포장의 노반에 적용될 때의 EPS회복탄성계수의 적합성을 연구하는 것이다. 적합성연구는 삼축압축시험의 결과를 토대로 이루어졌으며, 연성포장의 노반재료로써 EPS는 실험결과의 분석과 근본적인 회복탄성의 특성을 비교분석하여 그것의 적합성을 확인해 보았다.

• 한국유통학회지:유통연구
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• 제16권5호
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• pp.193-209
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• 2011

SSM(Super Supermarket) 출점이 사회적 논쟁이 되고 있고 출점을 저지하기 위한 다양한 규제가 마련되고 있는 중이다. 그러나 SSM 규제의 핵심이 진입제한에 있는바 경쟁 정책적 관점에서 그 타당성을 인정받기는 쉽지 않다. 그렇다면 적어도 보다 거시적 관점 즉 경쟁정책의 범위를 벗어나 사회적 정치적 목적에서 그 타당성을 인정받을 필요가 있을 것이다. 여기서 사회적 정치적 목적의 달성 여부는 '국민경제적 차원'에서 볼 때 규제 타당성이 성립할수 있는 지를 살펴보는 것을 의미한다. 본 논문은 국민경제적 차원을 지역상권의 활성화 차원으로 파악하고 SSM의 출점이 경쟁 소매업체에 대해 미치는 영향이 아닌 지역 상권에 대해 미치는 영향을 파악하는 것으로 연구 목표를 설정하였다. 아울러 본 연구는 이해당사자를 대상으로 한 설문 중심의 연구방법을 활용한 과거 연구의 약점을 일부라도 회피하고자 보다 객관적인 접근을 시도한다. 구체적으로 본 연구에서는 SSM 상권의 범위인 출점 반경 500m 이내에 위치한 편의점 매출액을 해당상권의 활성화 정도의 지표로 사용하고 이에 대한 업종별 점포비율의 변화, SSM의 출점 여부, 그리고 소매판매지수의 영향력을 평가하고자 한다. 이를 위해 편의점 매출액, 업종별 점포비율, 소매판매지수로 구성된 패널자료를 바탕으로 Swamy(1970)의 확률계수모델을 이용하였다. 그 결과 SSM(기업형 슈퍼마켓)의 출점 여부와 상관없이 편의점의 매출액이 증가하거나 감소하고 있기 때문에 SSM의 영향이 미비하거나 없는 것으로 나타났다. 편의점 매출액의 변화에 영향을 주는 많은 변수 중에서 소매업과 음식업의 경우 소매업 비율은 부의 관계를, 음식업 비율은 정의 관계를 나타났다. 이러한 결과는 소매업의 비율이 감소한다고 해서 상권 전체의 침체를 가져오는 것이 아니라는 주장을 지지하는 것으로 보인다.