• Ocean and Polar Research
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• v.41 no.3
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• pp.183-191
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• 2019

This study sought to find which model is most appropriate for estimating potential yield in the East Sea, Republic of Korea. For comparison purposes, the Process-error model, ASPIC model, Maximum entropy model, Observation-error model, and Bayesian state-space model were applied using data from catch amounts and total efforts of the whole catchable fishes in the East Sea. Results showed that the Bayesian state-space model was estimated to be the most reliable among the models. Potential yield of catchable species was estimated to be 227,858 tons per year. In addition, it was analyzed that the amount of fishery resources in 2016 was about 63% of the biomass that enables a fish stock to deliver the maximum sustainable yield.

• Journal of the Korean Society of Safety
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• v.30 no.5
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• pp.114-122
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• 2015

FMEA and FTA have been widely applied to the safety studies for railway systems respectively. But it would be more effective to use these two methods at a same time because these are complementary. This article suggests a FMEA-FTA combined analysis technique to evaluate the risk for railway systems. A FMEA-FTA combined risk evaluation model and process are proposed and a case study is dealt with for PBU(Pneumatic Breaking Unit), a major subsystem of a railway vehicle.

• Journal of the Korean Institute of Gas
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• v.4 no.4 s.12
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• pp.34-41
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• 2000

The purpose of this paper is to assess the R&D investment of Korea Gas Corporation (Kogas) by combining several measures including R&D needs, technology spillover effects, and technology stock at the corporate level. This study has revealed that Kogas has concentrated its R&D resources on the operation and maintenance of gas supply facilities, and technology groups, which have higher fulfillment of R&D needs and technology spillover effects, have been on the relatively greater level of technology stocks.

• Journal of the Korean Home Economics Association
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• v.35 no.5
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• pp.265-277
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• 1997

The purpose of this study are to identify the type and the amount of household's individual retirement account for retirement fund and to investigate the factors contributing to a individual pension account holding and an assessment. Data used in this study consisted of 2,667 households from 1994 KHPS. Statistics employed to analyze the data are Mean, Frequency, Percentile, Logistic and OLS. the result of this study were as follows; Among 2,677 households' 426 households(15.9%) owned the individual retirement account. Most household heads with individual retirement fund are the salaried and self-employed. More households with individual retirement account have saving account, stock than those without individual retirement account. Age, occupation of household head, total income, stock ownership had significant effects on whether household having individual retirement account. And Age of household head, net worth, saving account ownership had significant effects on the assessment of individual retirement account holding.

• Journal of Forest and Environmental Science
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• v.32 no.2
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• pp.120-128
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• 2016

Forest sequesters large terrestrial carbon which is stored in the biomass of tree and plays a key role in reducing atmospheric carbon. Thus, the objectives of the present study were to assess the growing stock, above ground biomass and carbon in trees of Ponda watershed of Rajouri district (J&K). IRS-P6 LISS-III satellite data of October 2010 was used for preparation of land use/land cover map and forest density map of the study area by visual interpretation. The growing stock estimation was done for the study area as well as for the sample plots laid in forest and agriculture fields. The growing stock and biomass of trees were estimated using species specific volume equations and using specific gravity of wood, respectively. The total growing stock in the study area was estimated to be $0.25million\;m^3$ which varied between $85.94m^3/ha$ in open pine to $11.58m^3/ha$ in degraded pine forest. However in agriculture area, growing stock volume density of $14.85m^3/ha$ was recorded. Similarly, out of the total biomass (0.012 million tons) and carbon (0.056 million tons) in the study area, open pine forest accounted for the highest values of 43.74 t/ha and 19.68 t/ha and lowest values of 5.68 t/ha and 2.55 t/ha, respectively for the degraded pine forest. The biomass and carbon density in agriculture area obtained was 5.49 t/ha and 2.47 t/ha, respectively. In all the three forest classes Pinus roxburghii showed highest average values of growing stock volume density, biomass and carbon.

• Computers and Concrete
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• v.16 no.1
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• pp.99-123
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• 2015

In this study, structural vulnerability of reinforced concrete moment resisting frames (RC-MRFs) by considering the Iran-specific characteristics is investigated to manage the earthquake risk in terms of multicomponent seismic excitations. Low and medium rise RC-MRFs, which constitute approximately 80-90% of the total buildings stock in Iran, are focused in this fragility-based assessment. The seismic design of 3-12 story RC-MRFs are carried out according to the Iranian Code of Practice for Seismic Resistant Design of Buildings (Standard No. 2800), and the analytical models are formed accordingly in open source nonlinear platforms. Frame structures are categorized in three subclasses according to the specific characteristics of construction practice and the observed seismic performance after major earthquakes in Iran. Both far and near fields' ground motions have been considered in the fragility estimation. An optimal intensity measure (IM) called Sa, avg and beta probability distribution were used to obtain reliable fragility-based database for earthquake damage and loss estimation of RC buildings stock in urban areas of Iran. Nonlinear incremental dynamic analyses by means of lumped-parameter based structural models have been simulated and performed to extract the fragility curves. Approximate confidence bounds are developed to represent the epistemic uncertainties inherent in the fragility estimations. Consequently, it's shown that including vertical ground motion in the analysis is highly recommended for reliable seismic assessment of RC buildings.

• Ocean and Polar Research
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• v.37 no.2
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• pp.161-177
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• 2015

This study analyzes the stock assessment of yellow croaker caught mainly by the Korean stow net and gill net fisheries focusing on single species and multiple fisheries. This study standardizes fishing efforts for the two fisheries using the general linear model and uses a surplus production model based on the exponential growth model. The Clarke Yoshimoto Pooley model estimates a maximum sustainable yield(MSY), an allowable biological catch(ABC), fishing efforts for MSY($E_{MSY}$) and for ABC($E_{ABC}$). The bio-economic model is used to estimate the maximum economic yield(MEY) and fishing efforts for MEY($E_{MSY}$). Also, the study employs an economic analysis to estimate the economic interaction between stow net and gill net fisheries. The economic analysis shows the profit accruing to the two fisheries from estimated ABC. Finally, the study compares TACs based on single species and single fishery to TAC based on single species and multiple fisheries. The study proposes that the TAC assessment is necessary for single species and multiple fisheries in order to preserve resources.

• Journal of The Korean Association For Science Education
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• v.22 no.2
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• pp.398-409
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• 2002

The purpose of this study was to investigate the validity, reliability and practicality of a concept map as an assessment tool in the context of biology concept learning. Forty undergraduate students participated in concept mapping, and the maps were scored by preservice science teachers, using one of three different scoring methods, that is, concept map scoring methods developed by Burry-Stock, Novak & Gowin and McClure & Bell. Two scorers were assigned to each scoring method. As far as the validity of the assessment methods was concerned, two of the three methods were found to be very valid, while Burry-Stock's scoring method was shown little valid. As far as the internal consistency of the methods was concerned, considerably high consistencies were shown between every pair of scorers, judging from high correlation coefficients between the pair of scorers for each scoring method. It took from 1.13 minutes to 3.70 minutes to assess a map at the average. It showed that concept mapping could be used in school classrooms with the limited resources of time and people. These findings suggest that the concept mapping can be an appropriate tool for assessing biology concept understandings.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.4
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• pp.857-861
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• 2021

The study aims to find the asymmetric effect in National Stock Exchange in which the Nifty50 is considered as proxy for NSE. A return can be stated as the change in value of a security over a certain time period. Volatility is the rate of change in security value. It is an arithmetical assessment of the dispersion of yields of security prices. Stock prices are extremely unpredictable and make the investment in equities risky. Predicting volatility and modeling are the most profuse areas to explore. The current study describes the association between two variables, namely, stock yields and volatility in equity market in India. The volatility is measured by employing asymmetric GARCH technique, i.e., the EGARCH (1,1) tool, which was used in building the study. The closing prices of Nifty on day-to-day basis were used for analysis from the period 2011 to 2020 with 2,478 observations in the study. The model arrests the lopsided volatility during the mentioned period. The outcome of asymmetric GARCH model revealed the subsistence of leverage effect in the index and confirms the impact of conditional variance as well. Furthermore, the EGARCH technique was evidenced to be apt in seizure of unsymmetrical volatility.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.5
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• pp.111-118
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• 2022

The purpose of this research is to evaluate the quality of non-financial information disclosure by companies listed on the Vietnamese stock exchange. In 2019, 140 annual reports from 140 companies listed on the Vietnam Stock Exchange were included in the research sample. The remaining 134 reports were eligible study after removing those that lacked essential data. Using the statistical software SPSS version 25 and Excel office software, the study has selected the data processing method and the disproportionate disclosure index method to evaluate the quality of non-financial information disclosure of companies. The findings of the study demonstrate that companies listed on the Vietnam stock exchange are particularly interested in giving non-financial information to financial statement consumers as required by law, although the level of disclosure is still inadequate. The findings also illustrate the varying levels of non-financial information disclosure by category of information, as well as substantial disparities between them (general information about the company, environmental and social information, corporate governance information, etc.). The findings of the study show that the majority of Vietnam's publicly traded enterprises are less interested in reporting environmental information.