• Journal of the Korean housing association
• /
• v.10 no.1
• /
• pp.51-61
• /
• 1999

Small apartment housings in Korea are dissatisfied due to the growing areas and changing lifestyle of the residents. Many of them currently confronted with slum areas and kinds of housing stock accumulated much more in Korean contexts. An extention of the existing small houses could be an adaptation model to the increasing requirement standards of the house residents. The new model could support diverse identification of the dwelling model in a settlement and many residents could be satisfied with the settlement. This paper deals with the unification typology of two dwelling units to one in order to remodel existing small apartment houses on the 15-pyung areas (N type) constructed by Korea National Housing Corporation in Naju. The proposed type of the merging of the dwellings remove concrete panel walls, make a path through balcony and attach a living areas to the front of the houses in order to make a circulation between the dwellings. A stair hall can be located in-between or inside the merged houses. It can also enhance privacy against conflictive activities in a house and possibly provide space appropriate for three-generation living. It can be devided for the multi-family use. Finally, the merging types of two dwelling units into one can be used as a device to get rid of the monotonous characteristics and gain diversity in the declining stock housing.

• Journal of Information Technology Services
• /
• v.10 no.3
• /
• pp.49-59
• /
• 2011

A ship scheduling model is presented for the raw material transportation problem with yard storage constraints in a steel mill. The problem is formulated as 0, 1 mixed integer programming considering such constraints as loading port conditions, ship size and hold capacity, unloading conditions, and yard storage space. In addition, inventory related constraints including safety stock are taken into consideration to support the continuous operations of steel making process. The proposed model has been implemented and applied successfully to a real world problem, and its results show the improvement of performance compared to the traditional method. For example, the arrival dates of ships are determined satisfying the constraints. The total inventory level is minimized at the stock yard as a result. Also, the safety inventory level is always kept at the planning stage, and the standard deviation of total inventory level is reduced significantly. Further research is expected to develop efficient heuristics to have a better response time for even larger scale problems.

• Journal of the Korean housing association
• /
• v.16 no.2
• /
• pp.83-90
• /
• 2005

A goal of this research is to propose the remodeling possibility from deteriorated stock apartment housing, to three generation family living in a dwelling unit for low incomes. An apartment housing which was built from 1970s, is accumulated over $55\%$ of the stock housing in Korea, many of them are confront with a rebuilding in a short usage of twenty years below. They are small one, and many of the residence complain narrow and small space compare to economic growth and their needs. This article deals the reform of two to one dwelling units, that it can be use for three generation family living as a new residence, because its spatial character is more controled privacy condition as a four bay spatial organization in the dwelling. The reform simulated in a 10, 13, 14, 15, and 16 pyung, the remodeling size became from 20 to 30 pyung, and its reform can be apply to extend life cycle of a stock confront with redevelopment. The possibility of the reform houses have more intensive privacy in a house compare with same area of new apartment. It tells us that we can recycle the deteriorate apartment house into three generation family living use, and it will be clue to change slum clearance into reform and recycle of deteriorate apartment house.

• Proceedings of the KSR Conference
• /
• 2010.06a
• /
• pp.124-132
• /
• 2010

To predict and analyze the rolling stock's fire growth is considered not only important factor in estimating hazard analysis of rolling stock, but also a primary factor in aspect of a rail load facility. Because it's could be regarded as a ignition source in risk assesment for the facility i.e. tunnel and station. However, currently, standardized method to predict and analyze the fire growth has not been completed yet. it is due to the fact that fire growth is not only depended on thermal property of interior materials, but also is affected dominantly by various factors such as ignition source (characterized by location, duration, and intensity), train running condition and in/exterior ventilation condition. Especially, ventilation condition is one of the most effective factor to affect fire growth in compartment space as noticed by under-ventilation fire condition. In this study, the effect of each ventilation condition on fire growth and load were examined through the numerical method through FDS (Fire Dynamics Simulator).

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.9
• /
• pp.147-158
• /
• 2020

We apply Return Dispersion Model by calculating CSAD (Cross-sectional standard deviation of return) and State Space Model to identify herding behavior in the period of pandemic (H1N1 and COVID-19). Employing data from TEJ and Data Stream, this paper examines whether the herding behavior is existing in Vietnam and Taiwan stock market, especially during pandemic influenza. We compare the differences in herding behavior between frontier and emerging markets by examining different industries across Vietnam and Taiwan stock market approaches. The results indicate solid evidence for investor herd configuration in the various industries of Vietnam and Taiwan. The herding impact in the industries will be greater than with the aggregate market. The different industries respond differently to influenza pandemic panics through uptrend and downtrend demonstrations. Up to 12 industries were found to have herding in Vietnam, while Taiwan had only 5 of 17 industries classified. Taiwan market, an emerging and herding-level market, has changed due to the impact of changing conditions such as epidemics, but not as strongly as in Vietnam. From there, we see that the disease is a factor that, not only creates anxiety from a health perspective, but also causes psychological instability for investors when investing in the market.

• Proceedings of the KSR Conference
• /
• 2009.05b
• /
• pp.437-443
• /
• 2009

Generally speaking, the uniqueness of Korea for the high-speed railway rolling-stock is mainly perceived through the travel over the high-speed electric railway by passengers, which consists of the organization of space in the coach and its interior design. For such purpose, it is necessary to build a series of independent cultures with high-speed railway i.e. to have the development of design technologies oriented to harmonizing human beings, their society and culture with the systematic integration of production technologies to support the culture and its substructure foundation which constitute the frame of superstructure in the society, by defining the relationships with travelers on the high-speed railway as well as enhancing the comfort and convenience of high-speed railway through drawing up the development of links with the systematic integration among lines of technologies on the basis of 'User Train Interface. This thesis aims at introducing the study carried out to build the evaluation standards of performance outputs for 'HEMU-400X rolling-stock Design' derived from the performance for the first year in the research 'Development of Technologies for the Next-Generation High-Speed Railway' as part of "Development Project for the Future Railway Technologies" from 2007.

• Journal of applied mathematics & informatics
• /
• v.20 no.1_2
• /
• pp.327-343
• /
• 2006

A general methodology is suggested to solve shelf-space allocation problem of retailers. A multi-item inventory model of breakable items is developed, where items are either complementary or substitute. Demands of the items depend on the amount of stock on the showroom and unit price of the respective items. Also demand of one item decreases (increases) due to the presence of others in case of substitute (complementary) product. For such a model, a Contractive Mapping Genetic Algorithm (CMGA) has been developed and implemented to find the values of different decision variables. These are evaluated to have maximum possible profit out of the proposed system. The system has been illustrated numerically and results for some particular cases are derived. The results are compared with some other heuristic approaches- Simulated Annealing (SA), simple Genetic Algorithm (GA) and Greedy Search Approach (GSA) developed for the present model.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.37 no.1
• /
• pp.141-150
• /
• 2014

Due to their accessibility and 24-hr availability, convenience stores are an integral part of daily lives. Because they sell a limited number of products and have small shelf space, shelf space allocation and inventory replenishment are important considerations for inventory management that critically affect profit. In this paper, we propose five solutions for the vendor-managed inventory problem of convenience stores that maximize profit while considering stock-out-based product substitutions. The performance of the proposed solutions is evaluated via simulation to reflect the demand uncertainty and marketing activity.

• Communications for Statistical Applications and Methods
• /
• v.29 no.6
• /
• pp.695-708
• /
• 2022

Recently, several studies have been conducted using state space model. In this study, a dynamic linear model with state space model form is applied to stock data. The monthly returns for 135 Korean stocks are fitted to a dynamic linear model, to obtain an estimate of the time-varying 𝛽-coefficient time-series. The model formula used for the return is a capital asset pricing model formula explained in economics. In particular, the transition equation of the state space model form is appropriately modified to satisfy the assumptions of the error term. k-shape clustering is performed to classify the 135 estimated 𝛽 time-series into several groups. As a result of the clustering, four clusters are obtained, each consisting of approximately 30 stocks. It is found that the distribution is different for each group, so that it is well grouped to have its own characteristics. In addition, a common pattern is observed for each group, which could be interpreted appropriately.

• Human Ecology Research
• /
• v.52 no.2
• /
• pp.165-173
• /
• 2014

The study was conducted to analyze whether the recent trends in preference toward small and medium-sized housing in Korea represent changes in space norms. To accomplish this, the existing data from Statistics Korea and two different empirical data sets collected in 2007 and 2012 from Ulsan, Korea, were statistically analyzed through descriptive statistics, cross-tabulation analysis with a chi-squared test and multiple regression analysis. In the analyses, the space norms of households were compared and any changes in the space norms and the related factors were determined. The space norms were mainly investigated in terms of the housing size and the number of rooms. The results are as follows: 1) since 2010, there have been changes in the housing stock distribution in terms of size. Stocks of small housing increased, while those of medium and large housing decreased. Nevertheless, the overall conditions of spatial density have improved considerably in the recent 30 years. 2) It was found that there were statistically significant differences between 2007 and 2012 in space norms. The norms for housing sized less than 99 m2 and with one or two rooms were found to have increased, while that for housing sized more than 132 m2 decreased. 3) Household size, education of the head, monthly household income, housing type and the number of bedrooms in the current dwelling were the significant explanatory variables of space norms.