• Title/Summary/Keyword: aggregate data

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The Change of Clothing Expenditures and its Determinants in Bores: A Time-series Analysis (Part I) (우리나라 소비자의 피복비 지출구조 변화양상과 결정요인에 대한 종적 연구(제1보))

  • 정수진;이은영
    • Journal of the Korean Society of Clothing and Textiles
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    • v.21 no.5
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    • pp.889-902
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    • 1997
  • During the past three decades, there have been drastic changes in many fields in Korea. Social and economic changes which occurred meantime have influenced clothing expenditures of Korean consumers. The purpose of this study was to investigate the change of clothing expenditures and its determinants in Korea during the period of 1965 to 1993. In particular, the impacts of income and price on clothing expenditures were examined using data from the National Acccounts published by the Bank of Korea as well as Urban Household Economy Survey published by the Bureau of National Statistics. Per-person consumption expenditures for clothing and shoes (CSX) in permanent price generally increased in accordance with the increase of income since 1965. From 1978 to 1984, however, there was a slight decrease in clothing expenditures in spite of the continuous increase in income, due to the depression of national economy. The proportion of CSX in total consumer spendings has decreased continuously since 1978. In recent years, CSX take only 5% of national aggregate consumption expenditures, while consumption expenditures of urban consumers is 8%. The expenditures for traditional clothing and fabrics for home- sewing decreased most. The results of this study should provide a broader view of the pattern of clothing consumption by Korean consumers. Moreover, the findings can suggest how social and economic changes of a society affect consumers' clothing expenditures.

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Parameterization for Longwave Scattering Properties of Ice Clouds with Various Habits and Size Distribution for Use in Atmospheric Models

  • Jee, Joon-Bum;Lee, Kyu-Tae
    • Atmosphere
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    • v.23 no.1
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    • pp.39-45
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    • 2013
  • A parameterization for the scattering of longwave radiation by ice clouds has been developed based on spectral scattering property calculations with shapes and sizes of ice crystals. For this parameterization, the size distribution data by Fu (1996) and by Michell and Arnott (1994) are used. The shapes of ice crystal considered in this study are plate, solid column, hollow column, bullet-rosette, droxtal, aggregate, and spheroid. The properties of longwave scattering by ice crystals are presented as a function of the extinction coefficient, single-scattering albedo, and asymmetry factor. The heating rate and flux by the radiative parameterization model are calculated for wide range of ice crystal sizes, shapes, and optical thickness. The results are compared with the calculated results using a six-stream discrete ordinate scattering algorithm and Chou's method. The new method (with various habits and size distributions) provides a good simulation of the scattering properties and cooling rate in optically thin clouds (optical thickness < 5). Depending on the inclusion of scattering by ice clouds, the errors in the calculation of the cooling rates are significantly different.

Evaluating the Economic Effects of Fishing Vessel Buyback Programs in Korea (우리나라 연근해어선 감척사업의 경제적 투자효과 분석)

  • Pyo, Hee-Dong
    • Ocean and Polar Research
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    • v.28 no.1
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    • pp.25-35
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    • 2006
  • Fisheries buyback programs have been implemented from 1994 in Korea, and its scale is estimated to have a value of 930 billion won, which is compounded for eight years since 1994. The paper evaluates the programs' economic and financial viability, and predicts efficient ways about how much and how long to reduce fisheries vessels so as to pursue a target biomass at MSY, For the specific purpose of the paper, aggregate fisheries stock dynamics and catch functions are specified and estimated by yearly catch and fishing effort data from 1970 to 2001, using ASPIC model and Schaefer's logistic production model. Results show that the fisheries stock in Korea has steadily declined since 1970, and that Korean fisheries overexploitation has steadily increased. Using cost-benefit analysis method, the buyback program holds the economic and financial feasibility even if the scale of buyback programs is not sufficient to avoid the downward trend in fisheries stock and harvest. The potential investment scale is predicted in several alternative scenarios using the sensitivity analysis method. The results recommend the annual reduction of 46%, 12% or 20% for the next one year, five years or three years, respectively so that the target biomass at MSY may be reached in 25 years.

Relationship between Accrual Anomaly and Stock Return: The Case of Vietnam

  • DANG, Hung Ngoc;TRAN, Dung Manh
    • The Journal of Asian Finance, Economics and Business
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    • v.6 no.4
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    • pp.19-26
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    • 2019
  • The study investigates the impact of accrual anomaly on stock return ratio of listed firms in Vietnam. Data were collected from listed firms for the period from 2008 to 2018. To learn about the causes of accrual anomaly in returns and future rate of returns on the Vietnamese stock market, this research is based on accrual analysis of Richardson, Sloan, Soliman, and Tuna (2006) on growth and effective components. We employ GLS regression model for examining the impact of accrual anomaly on stock return ratio and T-test for checking the difference between the lowest and the highest portfolio. The results show that accounting distortion is the main factor impacting the stock return, not growth determinant. Both two determinants of accounting distortion and growth contribute the explanation of the impact of accrual anomaly on profit and future stock return ratio. Experimental evidence confirms an abnormal existence of accrual in the Vietnam stock market. Aggregate accrual is negatively correlated with future operating profit and future stock return. However, after considering the factors contributing to the impact of future profitability and return on stock returns, the study results show that accounting distortion can account for low sustainability of income that is not growth.

Evaluation of Defect Types for Characteristic Database Construction of Large Sewage Box Culverts (대형 하수박스암거의 속성 데이터베이스 구축을 위한 결함유형 평가)

  • Han, Sangjong;Song, Homyeon
    • Journal of Korean Society of Water and Wastewater
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    • v.31 no.6
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    • pp.619-628
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    • 2017
  • As the 3D laser scanning technology capable of databaseing large sewage box culverts becomes possible, it is necessary to develop a standardization manual that can clearly distinguish the structural and operational defect types of box culver and analyze the defect data. In this study, we collected and analyzed defects in sewage box culverts of 14,827m in total by selecting three districts in Korea. The major defects were surface damages, and their defect densities were $2.17m^2/m$, $0.27m^2/m$ and $0.10m^2/m$ for aggregate exposure, Steel reinforcement exposure, and Steel reinforcement projecting. In order to support the decision of the box culverment management, it was divided into five grades and each defect code and defect score were allocated. The results of this study are useful for the diagnosis of the sewage box culverts in Korea and it is expected to support a decision making for management.

Generational Divides of Household Wealth and Propensity to Invest in Housing Asset - Baby-boomers and Eco-boomers in the Seoul Metropolitan Area - (세대 간 가계 자산구성 및 주택자산의 투자 성향 분석 - 수도권 거주 베이비부머와 에코세대를 중심으로 -)

  • Lee, Hyunjeong
    • Journal of the Korean housing association
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    • v.26 no.1
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    • pp.109-118
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    • 2015
  • The purpose of this research is to examine generational distinctions of housing investment and household wealth for two different age cohorts - 'baby-boomers' and 'eco-boomers'. In so doing, national survey data of two different periods were analyzed and the primary results are summarized as follows; aggregate assets of both generations have risen, and the rising household debt for baby-boomers was related to loans for living expenses while eco-boomer's debt was ascribed to home-buying loans. In the midst of economic slowdown, the age cohorts had conservative asset allocation in preference for risk-averting investment like savings. The main purpose of saving and investment was distinctive across the groups? retirement for baby-boomers and home purchase for eco-boomers. Both groups prioritized reduction of household liabilities and also were cautious on investing in real estate. Still home-buying was considered to be an important driver for asset accumulation. While baby-boomers were unwilling to dispose any form of owned real estate, eco-boomers found it challenging to take on a long-term investment like home-buying, especially in economic uncertainties. Rather the young generation would diversify asset allocation with better-returning investment commodities like stocks, bonds and derivatives.

A Fundamental Study on the Entrained Air Characteristics in Fresh Concrete by Fly-Ash Replacement and Air Entraining Agent (F/a치환량과 AE제 성분조절에 의한 콘크리트 내연행공기 특성에 관한 기초연구)

  • Yoo, Seung-Yeup;Lee, Sang-Rae;Koo, Ja-Sul;Kang, Suck-Hwa;Park, Myung-Ju;Ahn, Kyo-Duck
    • Proceedings of the Korea Concrete Institute Conference
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    • 2009.05a
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    • pp.423-424
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    • 2009
  • The use of fly-ash has been being increased to prevent alkali-aggregate reaction in concrete and to reuse industrial by-product. However the absorption of unburnt carbon to cement particles due to the increase of fly-ash usage decreases air content result in the risk at durability due to free-thawing. The properties of entrained air in fresh concrete, with various fly-ash replacement ratios and different types of air entraining agents, have been analyzed to suggest basic data for the stable air entraining property with large amount of fly-ash replacement in concrete.

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Prediction of Stress-Strain Relation and Evolution of Compliance of Concrete by a Micromechanical Model (미세역학이론에 의한 콘크리트의 응력-변형도 관계와 연성도의 예측에 관한 연구)

  • 김진구
    • Magazine of the Korea Concrete Institute
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    • v.8 no.3
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    • pp.147-155
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    • 1996
  • In this study a model for the constitutive relation of a plane concrete is proposed using a micromechariical model. In this model a precursor crack is assumed to exist in the aggregate-cement paste interface, and the LEFM is used to predict the nucleation of the bond cracks and the grow th of mortar cracks. For computational convenience the bond crack-mortar crack configuration is transformed into a straight crack with a point force in the middle. 'The overall compliance and the cons,titutive relation are predicted from the damage due to microcracks, and the predicted stress-strain curves are compared with some experimental data. According to the results, the model predictions are better for under tensile loading than under compression, for high, strength concrete than for normal strength concrete.

Numerical analysis of geocell reinforced ballast overlying soft clay subgrade

  • Saride, Sireesh;Pradhan, Sailesh;Sitharam, T.G.;Puppala, Anand J.
    • Geomechanics and Engineering
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    • v.5 no.3
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    • pp.263-281
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    • 2013
  • Geotextiles and geogrids have been in use for several decades in variety of geo-structure applications including foundation of embankments, retaining walls, pavements. Geocells is one such variant in geosynthetic reinforcement of recent years, which provides a three dimensional confinement to the infill material. Although extensive research has been carried on geocell reinforced sand, clay and layered soil subgrades, limited research has been reported on the aggregates/ballast reinforced with geocells. This paper presents the behavior of a railway sleeper subjected to monotonic loading on geocell reinforced aggregates, of size ranging from 20 to 75 mm, overlying soft clay subgrades. Series of tests were conducted in a steel test tank of dimensions $700mm{\times}300mm{\times}700mm$. In addition to the laboratory model tests, numerical simulations were performed using a finite difference code to predict the behavior of geocell reinforced ballast. The results from numerical simulations were compared with the experimental data. The numerical and experimental results manifested the importance that the geocell reinforcement has a significant effect on the ballast behaviour. The results depicted that the stiffness of underlying soft clay subgrade has a significant influence on the behavior of the geocell-aggregate composite material in redistributing the loading system.

The Impact of Trade Facilitation on the Extensive and Intensive Margins of Trade: An Application for Developing Countries

  • Lee, Hyo-Young;Kim, Chong-Sup
    • East Asian Economic Review
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    • v.16 no.1
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    • pp.67-96
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    • 2012
  • Previous literature has looked merely into the effect of trade facilitation on aggregate trade, or analyzed trade growth using the extensive and intensive margins. This paper blends these two lines of research for a detailed analysis of the impact of trade facilitation on trade by using highly disaggregated trade data and a more composite index for measuring trade facilitation, also taking into account the export sectors and income levels of countries. As a result, this paper finds that developing countries with higher trade facilitation levels export a wider range of products, especially primary goods. While trade facilitation levels do not have a statistically significant association with trade at the intensive margin in general, further analysis shows that the impact of advanced trade facilitation is the largest for lower middle-income countries in primary goods trade at the intensive margin, and the largest for upper middle-income countries in manufactured goods trade at the intensive margin. More importantly, our policy simulation results suggest that trade facilitation-related policy reforms enable developing countries to benefit from increased trade in manufactured goods at the extensive margin.

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