• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.6
• /
• pp.212-217
• /
• 2020

The purpose of this study was to analyze the volatility and properties of a time series for tangerine prices in Jeju using the GARCH model of Bollerslev(1986). First, it was found that the time series for the rate of change in tangerine prices had a thicker tail rather than a normal distribution. At a significance level of 1%, the Jarque-Bera statistic led to a rejection of the null hypothesis that the distribution of the time series for the rate of change in tangerine prices is normally distributed. Second, the correlation between the time series was high based on the Ljung-Box Q statistic, which was statistically verified through the ARCH-LM test. Third, the results of the GARCH(1,1) model estimation showed statistically significant results at a significance level of 1%, except for the constant of the mean equation. The persistence parameter value of the variance equation was estimated to be close to 1, which means that there is a high possibility that a similar level of volatility will be present in the future. Finally, it is expected that the results of this study can be used as basic data to optimize the government's tangerine supply and demand control policy.

• The Journal of Society for e-Business Studies
• /
• v.20 no.1
• /
• pp.201-215
• /
• 2015

Recently advanced security threats have increasingly occurred, and the necessity and importance of Information Security has been growing with the advent of the era of convergence beyond information-oriented age. Most domestic studies in the field of occupational classification of Information Security have only focused on technology-oriented occupations. Relatively little research has been carried out on the occupational classification in the view of convergence environment. Therefore, in this paper we gave a definition of Information Security occupations, classified them and draw required capabilities by occupations in order to design the occupational classification system of Information Security and the required capabilities for future convergence environment by analyzing the previous studies. We also reclassified the occupational classification and required capabilities by occupations, and verified the validity of them based on National Initiative for Cybersecurity Education's the occupational classification system of Information Security considering the future convertgence environment. It is expected that the results of this study will be employed as base data for manpower demand and supply and improvement of working conditions in the future convergence environments. In the future study we will build standardized instruction methods which provide occupational capabilities by using the required capabilities by occupations.

• The Journal of Society for e-Business Studies
• /
• v.19 no.3
• /
• pp.91-105
• /
• 2014

This study purposed to benchmark the number of patients who visited an oriental medicine hospital from its surrounding regions using data envelopment analysis (DEA) model, and to analyze the relationships between regional characteristics and efficiency scores from DEA. Study data was collected from one oriental medicine hospital operated in a metropolitan city in Korea. Patient locations were identified at the smallest administrative district, Dong, and number of patients was calculated at the Dong level based on the address of patients in hospital information system. Socio-demographic variables of each Dong were identified from the Statistics of Korea web-sites. DEA was used to benchmark the number of patients between Dongs and to compute the efficiency scores. Tobit regression analysis model was applied to analyze the relationship between efficiency scores and regional variables. 6 Dongs were identified as efficient after DEA. In Tobit analysis, number of medical aid recipients and number of total population in each Dong was significant in explaining the differences of efficiency scores. The study model introduced the application of DEA model in benchmarking the patients between regions. It can be applied to identify the number of patients in each region which a hospital needs to improve their performances.

• Land and Housing Review
• /
• v.5 no.1
• /
• pp.41-51
• /
• 2014

The amount of new apartment construction has been trending upward in 3~4% each year since 11% increase in 2002. Currently, in public apartment construction sites under separate delivery system for construction waste processing, the significant difference between estimated quantity for contract and actual amount frequently causes severe controversy among project participants. Many factors such as poor environmental management, inadequate contractual amount are assumed to influence the above problem, and the requirement to revise existing generation rates, the key criteria applied in estimating the quantities of waste, is increasing. Most of generation rates were established in early 2000's, and have difficulty in reflecting the changes from new materials and technologies accordingly. Therefore, this study aims to clarify the types of construction waste for each trade and the forecast method as preliminary work in order to develop more accurate generation rates for construction waste in new construction. To achieve this purpose, the architectural bills of quantities in ten apartment projects executed during 2010~2013 were collected, and the possible waste types and reasonable material loss ratio for each item from temporary works to owner-supplying material area were defined and compared through the workshops and interviews with the experts and on-site environmental managers. The results of this study will contribute to establishing the categories of construction waste for construction trades and proper generation rates by the indirect estimation method in new apartment construction in the follow-up study.

• Journal of the Korea Concrete Institute
• /
• v.26 no.4
• /
• pp.499-506
• /
• 2014

A number of studies on eco-friendly and healthy building materials are being conducted as modern people are becoming more conscious about health and the environment they live in. Among those materials, studies on Hwangtoh are the most prevalent but due to its strength, crack coming from drying shrinkage, and susceptibility to water, the usage of Hwangtoh is incomplete and limited to be used as a common building material. Cement concrete, considered as one of the most widely used building materials, is extensively used in construction because it is economical, easily accessible and moldable and has proper compressive strength. Due to carbon dioxide created in the process of making cement concrete, it is recognized as pollution. Accordingly, there are a lot of studies on reduction of carbon dioxide in cement concrete industry. There are increasing numbers of researches as well as developments on Hwangtoh or traditional construction materials used in South Korea to reduce the environmental problems. Therefore, this study suggests the basic features of the construction material that can replace cement concrete in the future with the non-sindtered cement mixed with non-sintering hwangtoh which is made with the furnace slag and multiple stimulants.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.48 no.2
• /
• pp.45-55
• /
• 2020

In terms of environmental justice, urban parks play a pivotal role in imperative amenities allowing for physical activity. The reasonable distribution of urban park services must be considered in terms of community demand and the context of the park. The purpose of this study is to analyze the inequity of qualitative park service according to the socioeconomic status(SES) in Daegu. The qualitative service was assessed for 82 neighborhood and walking-distance parks by utilizing the NGST(Neighborhood Green Space Tool). The inequity was analyzed by SES variables(ratio of basic living recipients, ratio of single-parent families, average housing sales, dilapidated dwelling ratio, and park area per capita). The features of the qualitative equity in Daegu is as follows. First, urban park planning in Daegu is in parallel with the development of residential areas rather than the local policy. The development pattern of parks stretching from center of the city to outskirts clearly dissociates the city based on socioeconomic status. The parks in the center are relatively old and poorly managed. Second, overall neighborhood parks lacked recreational facilities. The facilities are significantly influenced by the housing values around them. The lower the recreation facility score, the higher the floor gradient of the urban parks constraining physical activities. Third, the quantitative supply of parks has nothing to do with the quality of the urban parks. Green space distribution is highly dependent on natural park areas, so the park area per capita cannot be a standard for assessing qualitative equity.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.6
• /
• pp.861-866
• /
• 2012

Water is the most important resource for the potato cultivation, especially to get the maximum water use efficiency and yield of potato, Water has to be applied moderately based on the water requirement of the potato. Crop water requirement (WR) is a function of the Potential evapo-transpiration(PET) and Crop coefficient (Kc). PET can be estimated by the climate data measured at the weather station in the production region. Kc was measured by the NIAST (RDA) through Lysimeter experiments. In this study, the growth stage of potato was divided as four (G-1 : Apr. 1~Apr. 15, G-2 : Apr. 16~May. 10, G-3 : May. 11~May. 31, G4 : Jun. 1~Jun. 15). The average PET during potato growing season of the 45 areas was $2.95mm\;day^{-1}$. The most water requirement was the G-3 stage among the potato growth stage. The MWR (Mean water requirement) according to growth stage was 1.0~1.2 (average 1.1), 1.5~1.8 (average 1.6), 1.9~2.2 (average 2.0) and 1.7~2.1 (average 1.8) mm $day^{-1}$, in the G-1, G-2, G-3 and G-4 stage, respectively. The TWR (Total water requirement) according to growth stage was 18.0~22.1 (average 19.3), 50.6~66.6 (average 56.3), 63.5~88.2 (average 72.4) and 38.3~54.5 (average 44) mm, in the G-1, G-2, G-3 and G-4 stage, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.2
• /
• pp.440-447
• /
• 2020

The purpose of this study is to identify the causation and variation among the various types of onion prices in the major production sites to predict these prices. The Granger causal relationship was tested on the basis of VECM by setting the onion price of the early, middle, and late species as individual variables. The analysis shows that the amount of onions produced in the prior term affects the price of onions for the later period, while garlic in the substitution relationship with onions also affects the prices of onions for the early and middle-variety. On the other hand, the price of the late-variety is affected by the price of the early-variety, and the price of the middle-variety is also affected by the price of the early-variety. If the price of onions on Jeju changes due to other factors, the prices of onions in Jeollanam-do and Gyeongsangnam-do provinces will be affected. Accordingly, when the production of late-variety increases or decreases in production under any factor and to promote stability of the prices of middle and late-variety through preemptive supply and demand measures when the prices of ultra-breed onions rise or fall due to any factor (Ed- I cannot understand this last sentence and cannot guess at the correct meaning. Please try to rewrite very simply).

• The Journal of the Korea Contents Association
• /
• v.18 no.8
• /
• pp.51-61
• /
• 2018

This study was conducted to propose regional policy for reducing suicide rate by confirming the change of local suicide rate for 10 years from 2005 to 2015 and the effect of change of local environmental factors influencing the change. The main results are as follows. First, the change of city, county, and province suicide rate in 10 years showed that the suicide rate decreased in order of military district, city area, and district. Second, in the case of economic factors, local suicide rate decreased as the local tax burden per capita increased, and as the financial self - reliance increased. Third, in the case of the social integration factors, the local suicide rate decreased as the ratio of the basic livelihood recipient decreased. In addition, local suicide rate decreased as the number of elderly leisure welfare facilities increased. Fourth, in the case of the social demolition factor, the region where the divorce rate is increased, the depression experience rate is increased, and the region where the rate of one person is increasing, the local suicide rate is increased. Therefore, it is expected that the local suicide rate can be reduced through efforts to improve the economic capacity of the whole region, social integration and reduction of the social disintegration phenomenon in the region.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.6
• /
• pp.2680-2689
• /
• 2012

This study was aimed at finding out the relationship between the level of depression and the recognition and attitude of suicide and the study was conducted by a structured and self-filling questionnaire survey for 1,114 urban area students and 968 rural area students (totaled 2,082) in K city in the central districts of the country from July 1, 2009 to July 31, 2009. The result of the study showed that the more serious the level of depression, the higher the recognition and level of attitude for suicide was. Suicide attitude had a meaningful relationship with the degree of suicide recognition and the level of depression and the level of suicide recognition was closely connected with the level of depression. The result of the analysis of Hierarchial multiple regression showed the meaningfully related factors that affect the level of depression were sex, major, grade, school life satisfaction, fellowship with schoolmates, departing from girl or boyfriends, the lowest bracket of living standard, subjective health, smoking, financial status of household, a quarrel with parents and attitude of suicide. In particular, variables that are related to the condition of family life have high relationship with the level of depression.