• Title/Summary/Keyword: annual models

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Development of Diameter Growth and Mortality Prediction Models of Pinus Koraiensis Based on Periodic Annual Increment (정기평균생장을 이용한 잣나무 임분의 흉고직경 생장예측모델 및 고사예측모델의 개발)

  • Kim, Seonyoung;Seol, Ara;Chung, Joosang
    • Journal of Korean Society of Forest Science
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    • v.100 no.1
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    • pp.1-7
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    • 2011
  • The objective of this study was to improve the performance of the existing individual-tree/distantindependent stand growth model in predicting the growth of Pinus koraiensis forest stands. The parameters of diameter growth and mortality prediction models were estimated using periodic annual increment (PAI) of permanent plots and the performance of the models were compared with that of the existing ones using mean anuual increment (MAI). The diameter growth model includes crown ratio, potential diameter growth and modifier to compute for competitions of trees of a stand. In deriving the mortality prediction model, the parameters were estimated based on PAI which was also estimated as the function of MAI due to the lacking of permanent plot data. The results of this study showed that the newly-estimated functions based on PAI provide more realistic patterns in diameter growth of individual trees. The new approach using PAI in mortality model seems to overcome the over-estimate problem by the MAI-based model in estimating mortality of stand trees.

A Study on Estimation of Rainfall Erosivity in RUSLE (RUSLE의 강우침식도 추정에 관한 연구)

  • Lee, Joon-Hak;Jung, Young-Hun;Heo, Jun-Haeng
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.1324-1328
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    • 2008
  • RUSLE(Revised Universal Soil Loss Equation) is one of empirical models for estimating the soil loss effectively, when there is no measured data from the study areas. It has been researching into application and estimation of the RUSLE parameters in Korea. As one of the RUSLE parameters, the rainfall-runoff erosivity factor R, is closely connected hydrologic characteristics of the study areas. It requires a continuous record of rainfall measurement at a minute time step for each storm to calculate an accurate R factor by the RUSLE methodology and it takes a lot of time to analyze it. For the more simplified and reasonable estimation of the rainfall erosivity, this study researched for correlation between the rainfall erosivity and mean annual precipitation used 122 data from the existing studies in Korea. Considering hydrologic homogeneity, new regression equations are presented and compared with other annual erosive empirical index for the test of application. As the results, the study presents the isoerodent map at 59 sites in Korea, using annual rainfall data by the Korea Meteorological Administration from 1978 to 2007.

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Perenniality-Potential and challenges for future sustainable crop production

  • Paterson, Andrew
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.11-11
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    • 2017
  • The most drought resistant among the five most important cereal crops, and a key dual-use (grain and biomass) crop in regions containing some of the world's most degraded soils, sorghum has inherent climate resilience that is likely to become more important under environmental conditions that are projected by many climate change models. The importance of sorghum might be further elevated by the development of productive genotypes that increase the extent and duration of soil cover beyond those of conventional annual crops, mitigating or even reversing losses of ecological capital through multiple crops from single plantings. Rich genetic and genomic resources have been developed to link Sorghum phenotypic diversity to its molecular basis, and in particular the genus has become a model for dissecting the molecular control of perenniality. Nature has made Sorghum perennial at least twice, and crosses between wild perennials and cultivated sorghums show the feasibility of developing genotypes with varying degrees of investment in perenniality while still providing harvestable food, feed, sugar and/or cellulose. Genetic analysis of progeny from these crosses is revealing the hereditary basis of traits related to ratooning and perenniality and providing diagnostic DNA markers. One perennial Sorghum species has adapted to continents and latitudes far beyond the reach of its progenitors, surviving stresses year after year that are only periodically experienced by conventional (annual) sorghum, and may also harbor novel alleles that may mitigate production challenges in conventional annual sorghums.

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A Study of Economic Value Added Disclosures in the Annual Reports: Is EVA a Superior Measure of Corporate Performance?

  • Bhasin, Madan Lal
    • East Asian Journal of Business Economics (EAJBE)
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    • v.5 no.1
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    • pp.10-26
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    • 2017
  • This paper explains the concept of Economic Value Added (EVA) that is gaining popularity in India. We also examine whether EVA is a superior performance measure, both for corporate disclosure and for internal governance. Of late, companies in India have started focusing on shareholders wealth creation by adopting value-based models for measuring shareholder value that helps to align managerial decision-making with the firm preferences. In recent years, the EVA framework is gradually replacing the 'traditional' measures of financial performance on account of its robustness and its immunity from 'creative' accounting. Even though some leading Indian companies have already joined the band wagon of their American counterparts in adapting the EVA-based corporate performance systems, many other are hesitating as there is no strong evidence that the EVA system works in India. Till now, EVA disclosures are "not mandatory for the Indian companies." Also, we examine the value-creation strategies of selected Indian companies by analyzing whether EVA better represents the market-value of these companies in comparison to conventional performance measures. The study indicates that "there is no strong evidence to support Stern Stewart's claim that EVA is superior to the traditional performance measures in its association with MVA." As part of this study, we have also extensively surveyed the EVA disclosures in the Annual Reports made by the same sample group of 500 corporations from India.

A Study on Recalculation of the Long-Term Recycling Rate of New EPR Target Items (EPR 신규 대상품목의 장기 재활용목표율 재산정에 관한 연구)

  • Lee, Hee-Nahm;Choi, Yoon-Jeong
    • Journal of the Korea Safety Management & Science
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    • v.13 no.4
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    • pp.193-199
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    • 2011
  • In the past annual recycling obligation rate calculation of Extended Producer Responsibility (EPR) system, it was difficult to operate the system efficiently, because responsible producers passively participated in the scheme only bent on achieving annual obligation without long-term plan. Thus, a new scheme of long-term recycling obligation rate began to be established every five year from 2008 in order to give the basis for the notice of annual specific operation standard and recycling obligation, thereby helping responsible producers to make a preparation with a plan and giving expectation of active operation of the scheme. However, in the operation of long-term recycling target program, while the development of prediction models and the evaluation for existing items has been conducted in various ways, applications for a new target items and the evaluation are quite insufficient. Therefore, in this study, problems in implementing long-term recycling goal of new target items will be examined, and more objective and rational long-term recycling rate calculation and the operation standard will be proposed. Thus, the long-term recycling target will play a role as a pacemaker to steadily improve the recycling performance of target items, and responsible producers will be expected to increase the achievement with the realistic capacity.

The Energy Flow and Mineral Cycles In a Zoysia japonica and a Miscanthus sinensis Ecosystem on Mt. Kwanak 4. The Cycles of Phosphorus (관악산의 잔디와 억새 생태계에 있어서 에너지의 흐름과 무기물의 순환 4.인의 순환)

  • 장남기;김정석;강경미
    • Asian Journal of Turfgrass Science
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    • v.9 no.4
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    • pp.275-284
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    • 1995
  • In this investigation, the accumulation mineralization and annual cycle of organic P has been studied in grassland ecosysterns of a Z japonica grassland and a M sinensis grassland on Mt. Kwanak. The basic models of the accumulation and mineralization for ash components of a grass-litter have been presented as the equations (1), (2), and (3). The equations (7)~(10) for organic P are derived from these basic concepts. There was a highty significant relationship between organic matter and organic P. The estimates between organic matter and organic P correlated very high significance. The parameter factors k or k' of mineralization of organic P for the Z. japonica and M sinensis asslands were k=0.412 or k'=0.292 and k=0.224 or k'=0.183, respectively. The time required for a cycle to be completed from organic P to inorganic P of 50, 95 and 99 % are 3.9, 16.7 and 27.8 years in the Z. japonica grassland and 4.1, 17.7 and 29.4 years in the M sinensis grassland. The annual P cycle formulae for mineralization were based on the equations (5), (11) and (12). Annual yields of mineralization for organic P in the steady state grasslands of Z. japonica and M sinensis were 0.407 and 0.504g /$m^2$, respectively.

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A Study on Design of Movable Horizontal Shading Device for Office Building (사무소건물의 가동식 수평차양에 대한 연구)

  • Kim, Mi-Hyun;Suh, Seung-Jik
    • Journal of the Korean Solar Energy Society
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    • v.28 no.2
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    • pp.50-57
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    • 2008
  • This study intends to evaluate the effect on indoor environment(annual thermal load, sunshine)by the application of the movable horizontal shading device on summer and winter season. For these purpose, we supposed the models which are composed of the several horizontal shading devices. Then we analyzed the simulation using the IES5.5.1 and Seoul weather data. The results of this study are as follows: 1) The proper length, angle of horizontal shading device is 2.1m, 28 degree, respectively. 2) The decreasing rate of the annual load of the Movable Horizontal Shading Model(MHSM) in comparison with the No Shading Model(NSM) & Conventional Horizontal Shading Model(CHSM) is 31.11%, 6.63% respectively. 3) The decrease of sunshine of the MHSM on summer season is effective the alleviation of visual displeasure. On the other hand, the increase of sunshine of the MHSM on winter season is effective the psychological comfort. Further study is to be required the sensitivity analysis on the various shading length for the realistic proper shading length.

A Study on Estimating Container Throughput in Korean Ports using Time Series Data

  • Kim, A-Rom;Lu, Jing
    • Journal of Navigation and Port Research
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    • v.40 no.2
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    • pp.57-65
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    • 2016
  • The port throughput situation has changed since the 2008 financial crisis in the US. Therefore, we studied the situation, accurately estimating port traffic of Korean port after the 2008 financial crisis. We ensured the proper port facilities in response to changes in port traffic. In the results of regression analysis, Korean GDP and the real effective exchange rate of Korean Won were found to increase the container throughput in Korean and Busan port, as well as trade volume with China. Also, the real effective exchange rate of Korean Won was found to increase the port transshipment cargo volume. Based on the ARIMA models, we forecasted port throughput and port transshipment cargo volume for the next six years (72 months), from 2015 to 2020. As a result, port throughput of Korean and Busan ports was forecasted by increasing annual the average from about 3.5% to 3.9%, and transshipment cargo volume was forecasted by increasing the annual average about 4.5%.

A Study on the Optimum Design Flowrate for Tunnel-Type Small Hydro Power Plants

  • Lee, Chul-Hyung;Park, Wan-Soon
    • Korean Journal of Hydrosciences
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    • v.3
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    • pp.81-96
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    • 1992
  • This study represents the methodology for feasibility analysis of small hydro power SHP plant. Cumulative density function of Weibull distribution and Thiessen method were adopted to decide flow duration curve at SHP candidate site. The perfomance prediction model and construction cost estimation model for tunnel-type SHP plant were developed. Eight tunnel -type SHP candidate sites existing on Han-river were selected and surveyed for actual site reconnaissance. The performance characteristics and economical feasibility for these sites were analyzed by using developed models. As a result, it was found that the optimum design flowrate with the lowest unit generation cost for tunel-type SHP candidate site were the flowrate concerming with between 20% and 30% of time ratio on the flow duration curve. Additionally, primary design specifications such as design flowrate, effective head, capacity, annual averageload factor, annual electricity production were estimated and discussed for eight surveyed SHP candidate sites.

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An Economy Analysis on the Underground Food Storage (농수축산물저장을 위한 지하암반냉동창고의 경제성분석)

  • 김준홍
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.19 no.38
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    • pp.189-197
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    • 1996
  • It is in general reported that construction cost in an underground storage facility is less than that of the same capacity and features in an aboveground facility. Since these costs have a derivative with respect to facility size and fridging unit, the cost of construction and fridging unit are sensitive to location of storage, items to store, and rock quality of storage site. In this paper, to analyse an economic investment point for the underground food storage relative to aboveground storage, we compared these two models which have equivalent annual cost with the total cost that consists of initial facility investment cost and annual operation cost. Based on comparison of the economic investment in the underground with aboveground storage. an economic initial investment cost has been suggested for storing the agricultural and fish products.

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