• Journal of Korean Society of Environmental Engineers
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• v.27 no.4
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• pp.377-384
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• 2005

Algae causes not only the eutrophication of lake, but also the deterioration of drinking water process. Especially, algogenic organic matters(AOM) are assumed as disinfection by-products(DBPs) precursors like humic and fulvic acids. In this study, it was investigated the characteristics changes of algogenic organic matter(AOM) by prechlorination and coagulation treatment. Evaluation of enhanced coagulation and applicability of UV oxidation process were also evaluated as the drinking water treatment system for the eutrophicated water source. prechlorination was effective process for algae removal but caused releasing of dissolved organic matter(DOC) into water due to the destruction of algae's cell. In coagulation treatment with Fe(III) coagulant, reaction pH is an important factor for the removal of AOM and triholomathanes(THMs). At pH 5, removal efficiency of DOC and THMs were dramatically improved by 50% and 28%, respectively, in comparison with the conventional coagulation treatment at about pH 7. Photo-Fenton($UV/H_2O_2/Fe^{3+}$) process among the UV oxidations is the most effective system to remove AOM, but its removal efficiency was lower than that of enhanced coagulation treatment at pH 5.

• Journal of the Korean association of regional geographers
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• v.10 no.2
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• pp.447-465
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• 2004

This paper is to analyze citizens' consciousness on urban changes, especially focusing on changes in urban environment, spatial structure, and urban planning, of large cities in S. Korea, that is, Seoul, Daejeon, Daegu, and Kwangju in the 1990s. Some significant points can be described as follows. First. The most important factor influencing on the change of urban spatial structure was the expansion of residential area inner and outside of cities promoted by the traditional construction industry, and not development of high-tech industries and their complex or location of multi-national firms which can be emphasized as major factors of new urbanization process of global cities. Secondly, citizens seem to have experienced improvement and deterioration of urban environment simultaneously, emphasizing regulatory environmental policy on the one hand, and recognize the necessity of sustainable urban development within given environmental capacity and restoration of destructed and polluted environment of cities. Thirdly, the building boom of new apartment complex was a major driving force of changing urban spatial structure, but it could neither alleviate a residential gap between the poor and the rich areas nor a relief of traffic congestion. Finally, the urban policy in general was felt somewhat improved by citizens, but not in sectoral details.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.297-307
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• 2017

There are many underground spaces available in an urban environment and they represent an important factor for efficient land use. Especially, underground shopping centers perform both physical and commercial functions at the same time and are frequently used as a means of achieving the revitalization of the city center. However, the underground shopping centers that were developed in the past sometimes led to recession due to their deterioration. This study was carried out for the purpose of proposing alternative methods for the (revitalization) of underground shopping centers. A survey was conducted on seven underground shopping centers in the Busan metropolitan area to understand the factors that determine their user satisfaction and future improvement. The survey data was analyzed using an ordered logit model. As a result of the analysis, service satisfaction, underground environment satisfaction and public facility satisfaction were selected as significant variables. It was concluded that it is necessary to take these factors into consideration, appropriately, when developing a new or renewing an existing underground shopping mall.

• The Journal of the Korea Contents Association
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• v.18 no.5
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• pp.456-463
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• 2018

Increases in disasters and damage caused by the disasters in modern society, have a negative impact on local economy. In particular, a local economic downturn leads to a deterioration in quality of life of local residents and causes mental and material damage. Therefore, in order to achieve stable and sustainable local economic development, it is necessary to strengthen the resilience of the local economy. This study aims to estimate indicators of local economic resilience of Jindo County after the Sewol Ferry disaster, analyze a trend of the economic level after the disaster through time series data and suggest improvement plans of the local crisis management and restoration policy that considers future economic resilience. Results of this study showed that a decrease in the number of tourists and of workers in related industries hit tourism industry, causing a loss to the local economy and that an increase in a drinking rate of and stress awareness rate of local residents was a stress factor due to disaster impacts. These findings provides policy implications that it is necessary to make efforts for improving the depressed local image by utilizing local resources in the area, to build a sustainable long-term economic recovery policy and to provide psychological treatment and the relevant government and local government's support for relieving the stress of local residents due to the disaster impacts.

• Journal of Cadastre & Land InformatiX
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• v.48 no.1
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• pp.229-244
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• 2018

The purpose of this study is to analyze the factors affecting the influence of the size and composition of the floating population on goodwill and Rent. First, the conceptual difference between location value and rent is clearly distinguished. Second, the value of land price is divided into fixed land value and floating land value. The empirical analysis utilized consulting data from 188 shops in Seocho and Gangnam-gu in 2013 ( restaurants, resting restaurants, drinking places, general stores, entertainment and sports). The results using linear regression analysis are as follows. Goodwill and rent have a positive correlation, but the evaluation system and factors are different. Especially the influence of the floating location factor is larger than the rent. And the fixed location factors such as building deterioration bus stops, were found to be significant influencing factors in the rents, but they did not affect goodwill. This result implies that the value of location of goodwill should be taken into consideration of a temporal and spatial concept. Since, in order to resolve disputes between the landlord and the tenant, it is necessary to accumulate data continuously and to study the objective evaluation system in the future.

• Journal of Korea Port Economic Association
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• v.34 no.1
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• pp.51-64
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• 2018

The purpose of this paper is to analyze the productivity change of the Korean shipbuilding industry between 2001-2008 and 2008-2015 by using MPI(Malmquist Productivity Index) to decompose the sources of total factor productivity growth into technical efficiency change, scale efficiency change, pure efficiency change, technical change. The empirical results are as follows. In the first half of the year (2001-2008), productivity increased by 2.8%, which was due to technological advances rather than technical efficiency. In the second half (2008-2015), productivity change declined by -3.4%. This is attributable to the technical efficiency deterioration and technological degeneration caused by a decrease in shipbuilding orders due to the global economic downturn after the global financial crisis and the rise of Chinese shipbuilding industry. In the first half of the period, productivity change was higher than in the second half. Especially, the difference between the two periods is attributed to the technical change and it was proved by statistical verification. The policy implications of this paper suggest that the government and each DMU need to develop new technologies to cope with changes in the global shipbuilding industry environment and strategies to eliminate inefficiencies in order to increase productivity in the future.

• Korean Journal of Construction Engineering and Management
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• v.10 no.1
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• pp.91-101
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• 2009

The factors of uncertainty such as work delay could cause many problems, for example, increase of construction cost and terms of work, and the deterioration of quality. Because of these, the uncertainty risk is regarded as an important management factor to obtain the success of construction project. So, the systematic management plan about the uncertainty factors is needed because it plays an important role in the completion of entire project. And also analysis of some factors which can cause the work delay can be one way of improving construction project's certainty and making it competitive. In this reason, we have to make an effort to set a priority based on analysis of quantitatively numerical value about work delay factors to manage them effectively. Thus, this study aims to suggest the basic data for the effective management and prevention of work delay in steel-frame work which is progressive actively now, along with increasing of demand of high-rise buildings by analyzing each reasons of work delay factors and also by suggesting important management factors that are coded according to each construction work using FMEA method which could give a data about the importance of work delay factors through quantitatively numerical value.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.63-68
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• 1993

Heat penetration characteristics of retort pouched curry were studied to determine optimal sterilization conditions. Heating curve of retort pouched curry showed a simple logarithmic curve. The $f_h$ value (min.) of solid part in retort pouched curry was 1 min. higher than that of liquid part. $f_h$ value (min.) and $j_h$ value (heating lag factor) ranged from 8.3 min. to 12 min. and 1.0 to 1.17 respectively with increasing the ratio of solid to liquid and viscosity. $f_h$ value (min.) and $j_h$ value were significantly increased from 7.4 min. to 12.6 min. and 1.0 to 1.14 respectively with increasing thickness of the pouch from 11 to 15 mm. The low and medium volatile aroma components of retort pouched curry decreased during sterilization, which increased the high volatile aroma components. The retort pouched curry processed at $120^{\circ}C$, for 24 min. with $F_o$, value of $8{\sim}9$ could keep up a desirable quality without any remarkable deterioration.

• Elastomers and Composites
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• v.47 no.1
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• pp.9-17
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• 2012

Herein, life time prediction based on the deterioration of physical properties of chloroprene rubber (CR)aged by heat and seawater was performed. CR samples were experienced an accelerated test at $80^{\circ}C$, $100^{\circ}C$, $120^{\circ}C$ for heat aging, and $40^{\circ}C$, $60^{\circ}C$, $80^{\circ}C$ for seawater aging for 20,000 hrs. The change in tensile strength, maximum elongation,hardness was measured. As a result, the decrease in elongation was a major factor causing failure. The life time estimated using an Arrhenius model was 125 years at $23^{\circ}C$ for thermal aging and 9 years at $23^{\circ}C$ for seawater aging. SEM and elemental analysis reveal that cracks were generated and the content of oxygen was increased for CR agined by seawater. FT-IR spectrum shows the new C-O and C = O bonds were generated by the chemical reaction with seawater. Also, the glass transtion temperature was increased and the thermal decomposition was decreased by seawater aging.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.642-651
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• 2017

This study aimed to examine the changes in the health status, social network and satisfaction of caregivers as a result of caregiving using a structural equation model. As a result, it was found that caregiving increased the level of depression and decreased the subjective health status in both men and women. The social network and satisfaction were found to differ according to gender. For the women caregivers, caregiving affected their subjective health status and depression. In the case of the men caregivers, the total effect of caregiving on their subjective health was 1.087(p<.05), while the indirect effect was 0.546(p<.05). Also, caregiving affected the subjective health status of the male caregivers through the functional family network as a mediating factor(0.42, p<.01). The results suggest the necessity to take these gender differences into consideration when discussing the health of caregivers. Also, the functional family network needs to be strengthened to prevent the deterioration of the health status of male caregivers.