• Journal of Radiation Protection and Research
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• v.47 no.1
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• pp.30-38
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• 2022

Background: Residential areas have some factors on the external exposure of residents, who usually spend a long time in these areas. Although various survey has been carried out by the government or the research institutions after the Fukushima Daiichi Nuclear Power Plant accident, the mechanism of radiocesium inventory in the terrestrial zone has not been cleared. To better evaluate the radiation environment, this study investigated the temporal changes in air dose rate and ¹³⁷Cs inventories (Bq/m²) in residential areas and agricultural fields. Materials and Methods: Air dose rate and ¹³⁷Cs inventories were investigated in residential areas located in an evacuation zone at 5-8 km from the Fukushima Daiichi Nuclear Power Plant. From December 2014 to September 2018, the air dose rate distribution was investigated through a walking survey (backpack survey), which was conducted by operators carrying a γ-ray detector on their backs. Additionally, from December 2014 to January 2021, the ¹³⁷Cs inventories on paved and permeable grounds were also measured using a portable γ-ray detector. Results and Discussion: In the areas where decontamination was not performed, the air dose rate decreased faster in residential areas than in agricultural fields. Moreover, the ¹³⁷Cs inventory on paved surfaces decreased with time owing to the horizontal wash-off, while the ¹³⁷Cs inventory on permeable surfaces decreased dramatically owing to the decontamination activities. Conclusion: These findings suggest that the horizontal wash-off of ¹³⁷Cs on paved surfaces facilitated the air dose rate decrease in residential areas to a greater extent compared with agricultural fields, in which the air dose rate decreased because of the vertical migration of ¹³⁷Cs. Results of this study can explain the faster environmental restoration in a residential environment reported by previous studies.

• Korean Journal of Construction Engineering and Management
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• v.9 no.1
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• pp.187-198
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• 2008

There are usually plenty of material inventories in a construction site. More inventories can meet unexpected demands, and also they may have an economical advantage by avoiding a probable escalation of raw material costs. On the other hand, these inventories also cause negative aspects to increase costs for storing redundant inventory as well as decreasing construction productivity. Therefore, a proper method of deciding an optimal level of material inventories while considering dynamic variations of resources under uncertainty is very crucial for the economical efficiency of construction projects. This research presents a stochastic modelling method for construction operations, particularly targeting a work process involving on-site fabrication of raw materials like iron-rebar process (delivery, cut and assembly, and placement). To develop the model, we apply the concept of factory physics to depict the overall components of a system. Then, an optimal inventory management model is devised to support purchase decisions where users can make timely actions on how much to order and when to buy raw materials. Also, optimal time lag, which minimizes the storage time for pre-assembled materials, is obtained. To verify this method, a real case is applied to elicit an optimal amount of inventory and time lag. It is found that average values as well as variability of inventory level decreased significantly so as to minimize economic costs related to inventory management under uncertain project condition.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.487-488
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• 2010

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2009.10a
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• pp.199-201
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• 2009

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.681-682
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• 2010

• Journal of Environmental Impact Assessment
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• v.18 no.4
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• pp.235-243
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• 2009

Wetlands considered to be an important natural resources because they provide biodiversity and habitat for species to breed and survive. In this regard, many countries in the world provide wetlands and have policies and laws to protect them. In Korea we hosted RAMSAR COP-10 at Changwon in 2008 representing Korea's endeavor to wetland protection. But, in the process of development Wetlands are easy target to be lost due its easy access and the laws and regulations to protect them are relatively weak. Thus, this research focused on the introduction of No Wetland Loss(NWL) and we can achieve wetland protection in the economy market ways. Thus, NWL should consider 1) a clear definition of NWL and harmony and consensus of introduction of NWL, 2) considering most wetlands be private we need a financial support for securing wetlands, 3) inventories for wetlands in Korea, draw a line of demarcation, technic to evaluate wetlands, 4) wetland restoration considering function of ecosystem not total amount of wetlands. Wetland protection should be a part of Basic Law of Water Management which in its progress and we need further studies on wetland protection because of watershed management, deserted agricultural paddies, etc.

• IE interfaces
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• v.21 no.4
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• pp.418-434
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• 2008

This paper studied issues in decision making on the production control policy of a cathode plate manufacturing process in zinc refining plant. The present production system has a long lead time from raw materials (aluminum plate) to products (cathode plate) due to many WIP inventories. Because WIP inventories are stocked at each process and moved from one place to another frequently, they are the main cause of inefficiency in the process. In this paper, to solve this problem, several production control policies have been identified and studied. Several simulation models are used to compare the performances of these production control policies. The output lead time and WIP (Work In Process) of real production system are compared with those of simulation models. PUSH, CONWIP, DBR, KANBAN and CONWIP-DBR models have been used to simulate and review the optimized production control policy that achieves the target output quantities with decreased lead time and WIP. The simulation results of each production control policy show that CONWIP and CONWIP-DBR models are the good production control policy under the present production system. Especially in present production system, CONWIP with one parameter is easier control policy than CONWIP-DBR with two parameters. Therefore CONWIP has been selected as the best optimum production control policy. With CONWIP, lead time has been reduced by 97% (from 6,653 to 187 minute) and WIP has been reduced from 1,488 to 53, compared to the present system.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.3
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• pp.316-324
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• 2012

This research shows the improved methodology which can be applied for universities which want to set up their GHG inventories. In other words, we tried to make guideline in problems due to the unique characteristics of universities. This guideline will help university to deal with the problems they are facing: For example university has less enforcement in operational control compared to the business sector. And it also has various usage of facilities, although these facilities are not maintained by same principal agent. The difference between owner and manager is an another reason for difficulty in setting group organization. The improved and adaptable methods responding to these problems were suggested from this research. The results of this research says the new definition of function for various actors in university for quality control and quality assurance. Because the suggestions made in this research which concerns with criteria for building of universities' GHG inventories were all read by current legislation, there is an anticipation that this can be an official guideline that can be applied to the universities right away.

• Journal of Korean Academy of Nursing
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• v.14 no.1
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• pp.50-59
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• 1984

The purpose of this study was to evaluate the maternal perception of her newborn and identify the risk of mother-infant relationship. Broussard's Neonatal Perception Inventories were completed by 113 mothers on the first or second postpartum day (Time I ) while they were still in the University Hospital. These inventories were again administered when the infants were approximately one month of age (Time Ⅱ). The data was analyzed by S.P.S.S. program and the results were as follows: 1) There were differences between the mothers' exportations of the average baby and perceptions of their babies at Time I and Time Ⅱ (p<0.01). 2) The maternal perception of her newborn at Time I was not related with the education, the parity, the experience of abortion, the type of delivery and the sex of baby but related with the method of feeding (p<0.05). 3) The maternal perception of her newborn at Time Ⅱ was not related with the education, the parity, the experience of abortion, the type of delivery and the method of feeding but related with the sex of baby (p<0.05). 4) The changes of maternal perception between Time I and Time Ⅱ were not related with the education, the parity, the experience of abortion, the method of delivery and the sex of baby but related with the method of feeding (p<0.1). 5) The maternal perception of the newborn was not correlated with the age and the duration of labor.

• Journal of Distribution Science
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• v.15 no.3
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• pp.17-25
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• 2017

Purpose - The study is to examine the impact of the US Purchasing Managers' Index (PMI) on Korea and the US industrial economy including the distribution industry. We analyze its effect on the industrial economy centered on the distribution industry using economy indices in Korea and the US. Research design, data, and methodology - The variables are used to analyze the dynamic relationship which occurs among the US PMI, the industrial production index, producer price index, unemployment rate, and manufacturing Inventories Index in Korea and the US from January 1990 to July 2016 using Vector Error Correction Model. Results - As a main result, the impact of the US PMI on all the economy indices both Korea and the US has the same cyclical movement. The US PMI is positively related to the producer price and the industrial production index of Korea and the US, while it is negatively related to unemployment rate, and the manufacturing inventories index in Korea and the US. Conclusions - The US PMI as an advanced index has a power to predict the economies on Korea and the US. In the end, we find that the US PMI has a great impact on Korea and the US industrial economy.