• Journal of Korean Society of Transportation
• /
• v.19 no.5
• /
• pp.21-33
• /
• 2001

Intelligent Transport Systems (ITS) was first introduced in Korea early 1990's, and Korean government has put a lot of efforts for flourishing it in the entire nation. Regardless of these efforts, private participation is not active enough to accelerate ITS implementation in Korea. Expert group made every endeavor to analyze the current situation, and found out some phenomena. It may be summarized as two folds. Firstly, private sector has a lack of confidence on the future ITS market. Budget in the strategic plan is the only publication and guide that private sector can refer to, and it merely indicates deployment costs. Secondly, direction and procedure of R&D are not well defined. It implies that private sector takes too much risk when they invest for R&D. This research, therefore, focuses on the first issues. Concretely, the goal of the project was to establish and analyze the model for estimation the future ITS market side. Author reviewed both quantitative and qualitative models, and concluded that diffusion model in qualitative model was suitable for ITS market estimation. According to model calibration. it is estimated that 14 trillion Won was the market size in 2020 under normal condition. Impact of this result may seduce Information Technology(IT) related private companies into ITS market. Although this research couldn't cover various topics, it nay dedicate in boosting ITS in Korea. Also, it will be a good starting point for further study for the advancement of ITS.

• Korean Journal of Social Welfare
• /
• v.68 no.3
• /
• pp.51-71
• /
• 2016

The purpose of this study is to clarify macro causes influencing on the diversity of single-mother households poverty among OECD Countries including Korea. This study carried out pooled time series cross-section analysis applying unbalanced panel design on the period from 1981 to 2012. There is marked diversity on single-mother households poverty. GDP per capita does not contributes to reduce poverty, and female employment rate and % population 0-14 exacerbate poverty. Several factors contribute on poverty reduction including social spending, child cash spending, union density, employment protection on regular workers, proportional representation system, cumulative left cabinet, cumulative women seat. In Korea, it needs to overcome the limit of anti-poverty strategy mainly based on economic growth and labor market flexibility. And it needs to enlarge universal welfare institutions, child benefits, work-family reconciliation policy, and to design adjusted labor market institutions including union density and employment protection, to introduce consensus political model including proportional representation system to enhance left power and women's representation.

• Journal of Intelligence and Information Systems
• /
• v.29 no.1
• /
• pp.377-396
• /
• 2023

As the cryptocurrency market continues to grow, it has developed into a new financial market. The need for investment strategy research on the cryptocurrency market is also emerging. This study aims to conduct an empirical analysis on an investment methodology of cryptocurrency that combines short-term trading strategy and deep learning. Daily price data of the Ethereum was collected through the API of Upbit, the Korean cryptocurrency exchange. The investment performance of the experimental model was analyzed by finding the optimal parameters based on past data. The experimental model is a volatility breakout strategy(VBS), a Long Short Term Memory(LSTM) model, moving average cross strategy and a combined model. VBS is a short-term trading strategy that buys when volatility rises significantly on a daily basis and sells at the closing price of the day. LSTM is suitable for time series data among deep learning models, and the predicted closing price obtained through the prediction model was applied to the simple trading rule. The moving average cross strategy determines whether to buy or sell when the moving average crosses. The combined model is a trading rule made by using derived variables of the VBS and LSTM model using AND/OR for the buy conditions. The result shows that combined model is better investment performance than the single model. This study has academic significance in that it goes beyond simple deep learning-based cryptocurrency price prediction and improves investment performance by combining deep learning and short-term trading strategies, and has practical significance in that it shows the applicability in actual investment.

• Journal of the Korean Geographical Society
• /
• v.49 no.4
• /
• pp.525-545
• /
• 2014

This study seeks to clarify the influence of the stage migration which has proceeded through generations, on the population growth of local cities in the case of Jeollabuk-do. For this, setting to baby boomer as parents generation and echo boomer as their children, this study traces each generation's birth, distribution and the process of selective migration using aggregate level data. And the stage migration is analyzed by O-D, divided into three regions in each; Jeollabuk-do rural areas, Jeollabuk-do cities and other provinces. The major findings of this study are as follows. First, it was estimated that the number of the baby boomer births in Jeollabuk-do rural areas was seven times more numerous than in cities. Second, both rural and urban born baby boomers overwhelmingly moved into other provinces, especially Seoul metropolitan area and metropolis in their selective migration processes. However, there was also migration stream from rural areas to cities in Jeollabuk-do and the amount of this stream was approximately equal to the amount of outflux from cities in Jeollabuk-do to other provinces. Third, due to baby boomers' stage migration, from rural to urban, echo boomers were born in cities more than in rural areas. Fourth, urban born echo boomers still have moved into other provinces just like their parents generation in selective migration process. But comparing with baby boomer, the number of echo boomers influx from rural areas to cities has decreased. Consequentially the population of echo boomer in Jeollabuk-do cities also has decreased. Finally, the stage migration has been a basic cause of the social growth of urban population, and also influenced on the natural growth, closely connected with migrants' life course, such as marriage, childbirth and rearing. Therefore, this study concludes that the stage migration through generations is one of the crucial factor to understand the population growth in local cities.

• Journal of Korean Society of Forest Science
• /
• v.77 no.4
• /
• pp.429-444
• /
• 1988

Considering the recent trent toward the development of multiple-use of forest trees, investigations for comprehensive information on these young stands of Hinoki cypress are necessary for rational forest management. From this point of view, 83 sample trees were selected and cut down from 23-ear old stands of Hinoki cypress at Changsung-gun, Chonnam-do. Various stem growth factors of felled trees were measured and canonical correlaton analysis, principal component analysis and factor analysis were applied to investigate the stem growth characteristics, relationships among stem growth factors, and to get potential information and comprehensive information. The results are as follows ; Canonical correlation coefficient between stem volume and quality growth factor was 0.9877. Coefficient of canonical variates showed that DBH among diameter growth factors and height among height growth factors had important effects on stem volume. From the analysis of relationship between stem-volume and canonical variates, which were linearly combined DBH with height as one set, DBH had greater influence on volume growth than height. The 1st-2nd principal components here adopted to fit the effective value of 85% from the pincipal component analysis for 12 stem growth factors. The result showed that the 1st-2nd principal component had cumulative contribution rate of 88.10%. The 1st and the 2nd principal components were interpreted as "size factor" and "shape factor", respectively. From summed proportion of the efficient principal component fur each variate, information of variates except crown diameter, clear length and form height explained more than 87%. Two common factors were set by the eigen value obtained from SMC (squared multiple correlation) of diagonal elements of canonical matrix. There were 2 latent factors, $f_1$ and $f_2$. The former way interpreted as nature of diameter growth system. In inherent phenomenon of 12 growth factor, communalities except clear length and crown diameter had great explanatory poorer of 78.62-98.30%. Eighty three sample trees could he classified into 5 stem types as follows ; medium type within a radius of ${\pm}1$ standard deviation of factor scores, uniformity type in diameter and height growth in the 1st quadrant, slim type in the 2nd quadrant, dwarfish type in the 3rd quadrant, and fall-holed type in the 4 th quadrant.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.10 no.1
• /
• pp.7-14
• /
• 2006

The finite failure NHPP models proposed in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, we propose the Erlang reliability model, which can capture the increasing nature of the failure occurrence rate per fault. Equations to estimate the parameters of the Erlang finite failure NHPP model based on failure data collected in the form of inter-failure times are developed. For the sake of proposing shape parameter of the Erlang distribution, we used to the goodness-of-fit test of distribution. Data set, where the underlying failure process could not be adequately described by the existing models, which motivated the development of the Erlang model. Analysis of the failure data set which led us to the Erlang model, using arithmetic and Laplace trend tests, goodness-of-fit test, bias tests is presented.

• Journal of Wetlands Research
• /
• v.14 no.3
• /
• pp.341-352
• /
• 2012

The purpose of this study is to statistically project future probable rainfall and to quantitatively assess a future flood vulnerability using flood vulnerability model. To project probable rainfall under non-stationarity conditions, the parameters of General Extreme Value (GEV) distribution were estimated using the 1 yr data added to the initial 30 yr base series. We can also fit a linear regression model between time and location parameters after comparing the linear relationships between time and location, scale, and shape parameters, the probable rainfall in 2030 yr was calculated using the location parameters obtained from linear regression equation. The flood vulnerability in 2030 yr was assessed inputted the probable rainfall into flood vulnerability assessment model suggested by Jang and Kim (2009). As the result of analysis, when a 100 yr rainfall frequency occurs in 2030 yr, it was projected that vulnerability will be increased by spatial average 5 % relative to present.

• The KIPS Transactions:PartD
• /
• v.15D no.3
• /
• pp.313-320
• /
• 2008

A typical software development life cycle consists of a series of phases, each of which has some ability to insert and detect defects. To achieve desired quality, we should progress the defect removal with the all phases of the software development. The well-known model of phase-based defect profile is Gaffney model. This model assumes that the defect removal profile follows Rayleigh curve and uses the parameters as the phase index number. However, these is a problem that the location parameter cannot present the peak point of removed defects when you apply Gaffney model to the actual situation. Therefore, Gaffney model failed to represent the actual defect profile. This paper suggests two different models: One is modified Gaffney model that introduce the parameter of Putnam's SLIM model to replace of the location parameter, the other is the growth function model because the cumulative defect profile shows S-shaped. Suggested model is analyzed and verified by the defect profile sets that are obtained from 5 different software projects. We could see from the experiment, the suggested model performed better result than Gaffney model.

• Composites Research
• /
• v.14 no.5
• /
• pp.46-53
• /
• 2001

In this research, damage behavior of singly oriented ply (SOP) fiber metal laminate (FML) subjected to concentrated load was studied. The static indentation tests were conducted to study fiber orientation effect on damage behavior of FML. During the static indentation tests, acoustic emission technique (AE) was adopted to study damage characteristics of FML. AE signals were obtained by using AE sensor with 150kHz resonance frequency and the signals were compared with indentation curves of FML. The damage process of SOP FML was divided by three parts, i.e., crack initiation, crack propagation, and penetration. The AE characteristics during crack initiation show that the micro crack is initiated at lower ply of the plate, then propagate along the thickness of the plate with creating tiber debonding. The crack grow along the fiber direction with occurring 60∼80dB AE signal. During the penetration, the fiber breakage was observed. As fiber orientation increases, talc fiber breakage occurs more frequently. The AE signal behaviors support these results. Cumulative AE counts could well predict crack initiation and crack propagation and AE amplitude were useful for the prediction of damage failure mode.

• The Journal of the Korea Contents Association
• /
• v.7 no.5
• /
• pp.166-173
• /
• 2007

This study analyzed the valuation of stock market for marketability of mobile contents. We investigated, during the period of 2002 to 2005, the anormal returns of each firms which announced the launching of new mobile contents. As a result, we found statistically significant average abnormal return(AAR) at launching day of new mobile contents. And the meaningful average cumulative abnormal returns(ACAR) are observed during event period. Which means that the launching announcement of new mobile contents leads to statistically significant positive abnormal returns at stock market. Therefore, we concluded that stock market react immediately to new mobile contents, and which valuate only specific value but also implied value of contents.