• Journal of Korean Society on Water Environment
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• v.24 no.5
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• pp.611-617
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• 2008

It is necessary to analysis the data characteristics of discharge and water quality for efficient water resources management, aggressive alternatives to inundation by flood and various water pollution accidents, the basic information to manage water quality in lakes and to make environmental policy. Therefore, the present study applied Self-Organizing Map (SOM) showing excellent performance in classifying patterns with weights estimated by self-organization. The result revealed five patterns and TOC versus rainfall-storage data according to the respective patterns were depicted in two-dimensional plots. The visualization presented better understanding of data distribution pattern. The result in the present study might be expected to contribute to the modeling procedure for data prediction in the future.

• Journal of Environmental Health Sciences
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• v.26 no.2
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• pp.70-79
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• 2000

This study was done for the purpose of investigating the status of the use and perceptions of pesticides among the farmers who spray them in person. And it was also done to provide the basic statistics for the Agricultural Health Policy and study. Over the part of agricultural area in Kyungju and Ulsan City, Korea, from July to September 1999, 1032 questionnaires were distributed and 561 of them were collected and 447 were analysed. Major results of this study are as follows. The proportion of those who have special location for pesticides storage was only 5.3%, and that of those who lock hte storage location was only 13.6%. As to the treatment of bottles after use, most common response was 'burn in home'(47.7%). Most farmers purchase pesticides through 'pesticide store' or 'Agricultural Cooperatives'. The knowledge and Usage of pesticides depends in large part on experiences. The farmers who cultivate orchard spray pesticides more frequently than those cultivate paddy rice mainly. Most common pesticides in use are oganophosphates and carbamates. And also the pesticides that contains so-called 'Environmental Hormone' are used. The perception about the hazards of pesticides is rather superficial and insufficient. 'Herbicide(Gramoxon·Paraco)'(38%) is accepted as the most hazardous by farmers.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.6
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• pp.611-618
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• 2016

The suggested paper studies communications network and system technology, designing data to sync to both USB memories and cloud storages at the same time, which would allow users to safely keep and manage data even in case of network troubles, affecting cloud storages, and/or loss of physical USB memories, resulting in lost data in the physical memory. The need of secure data management policy for cloud storage users form the basis of this study, offering solutions to network failures and loss of physical storage by creating hybrid cloud system. To provide convenience to windows users, the UI design should integrate that of windows explorer to maximize security and convenience.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.1
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• pp.3-13
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• 2004

For optimal irrigation reservoir operation during flood and normal period, a general and systematic policy is suggested to make balance of the conflicting purposes between water conservation and flood control. We developed Open Water Management Program (OWMP) with an open architecture to deal with newly arising upgrade problems for optimal management of irrigation reservoir. And we evaluated the applicability of OWMP to estimate daily runoff from an agricultural watershed including irrigation reservoirs, and analyzed behaviour of irrigation reservoirs as irrigation water requirements considering frequency analysis of reservoir storage and frequency analysis water requirements for effective management of reservoir. When we executed OWMP with data produced from an experimental field, IHP basins, the mean relative errors of application of daily runoff and irrigation water requirement were less than 5％. We also applied OWMP to a Seongju irrigation reservoir to simulate daily runoff, storage and water requirement from 1998 to 2002, and the mean model efficiency between measured and simulated value was 0.76. Our results based on the magnitude of relative errors and model efficiency of the model simulation indicate that the OWMP can be a tool nicely adapted to the effective water management of irrigation reservoir for beneficial water use and flood disaster management.

• Journal of the Korean Society of Industry Convergence
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• v.21 no.5
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• pp.207-217
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• 2018

Recently, the importance of energy demand management, particularly peak load control, has been increasing due to the policy changes of the Second Energy Basic Plan. Even though the installation of distributed generation systems such as Photovoltaic and energy storage systems (ESS) are encouraged, high initial installation costs make it difficult to expand their supply. In this study, the power consumption of a university building was measured in real time and the measured power consumption data was used to calculate the optimal installation capacity of the Photovoltaic and ESS, respectively. In order to calculate the optimal capacity, it is necessary to analyze the operation methods of the Photovoltaic and ESS while considering the KEPCO electricity billing system, power consumption patterns of the building, installation costs of the Photovoltaic and ESS, estimated savings on electric charges, and life time. In this study, the power consumption of the university building with a daily power consumption of approximately 200kWh and a peak power of approximately 20kW was measured per minute. An economic analysis conducted using these measured data showed that the optimal capacity was approximately 30kW for Photovoltaic and approximately 7kWh for ESS.

• Journal of Korean Society for Quality Management
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• v.49 no.2
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• pp.161-170
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• 2021

Purpose: The purpose of this study was to evaluate the economic value of installing public Energy storage system (ESS) facilities using a logit regression analysis and Contingent Valuation Method (CVM). We focused mainly on the environmental benefits of ESS and analyzed how the users' attitude toward environmental protection and knowledge of renewable energy affect their Willingness to pay (WTP) Methods: A single-bounded dichotomous choice (SBDC) survey was used to collect the data. We asked participants whether they are willing to pay a randomly presented cost (KRW 100, 500, 1000, 1500, 2000, 2500, 5000, 10000) along with their attitude to toward environmental protection, knowledge of renewable energy, and perceived cost of electric bill. 417 valid samples were collected and used for the analysis. Results: The results of the logit regression show that the initial bid, attitude toward environmental protection, knowledge of renewable energy, and perceived cost of electric bill significantly affect the user's WTP of public ESS facilities. The CVM results show that users are willing to pay KRW 5,049.1/month to install ESS facilities. Conclusion: : According to results, we conclude that the users agree with the need to install ESSs and that environmental benefits of ESSs are important factors for ESS adoption. Therefore, policy makers need to emphasize environmental aspects to install the ESS facilities.

• Journal of Distribution Science
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• v.20 no.7
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• pp.57-64
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• 2022

Purpose: The government of India has initiated the Covid-19 Vaccination drive from early January 2021. Vaccination is identified to be best option to protect the people across the globe. However, owing to fast wide spread of the Covid-19, the Vaccine Distribution is a major challenge owing various issues like temperature control, infrastructure, hesitancy, geographical diversity, and other critical factors. Various research is carried out globally to understand and study the Vaccine Distribution issues based on the respective country issues and factors. Research Design, Data, and Methodology: This research paper attempts to explore prominent factors that could be taken up on priority for better and effective vaccination program. The study tries to rank various factors and sub-factors affecting vaccine distribution in India. AHP methodology based on feedback from 22 experts from the Vaccine industry has been deployed to get the desired results. Result: The results show that factors vaccine approval process, geographical prioritization, power supply, infrastructure maintenance costs for vaccine storage, and vaccine pricing are the prominent factors of effective vaccination in the country. Conclusion: The role and need for district-level health officers towards vaccine storage has been brought forward. A long-term effective vaccination policy is needed for optimum vaccine distribution.

• Korean Journal of Environment and Ecology
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• v.24 no.5
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• pp.591-600
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• 2010

We estimated and compared C storages and annual $CO_2$ uptakes by 9 dominant tree species planted along the streets. DBH and age by tree species were measured in the sites selected considering the planting status and distributions of tree species, and biomass, C storage, growth rate, and annual $CO_2$ uptake were estimated for each species. As a result, L. tulipifera, M. glyptostroboides, P. occidentalis were classified into fast-growing group, P. serrulata, G. biloba, Z. serrata, S. japonica, A. palmatum showed intermediate growth rates, and P. densiflora was slow-growing. Average C storage per tree was 205kgC/tree and ranged from 518kgC/tree(L. tulipifera) to 41kgC/tree(P. densiflora). Average annual $CO_2$ uptake by urban street trees over their lifespan ranged from $7.6kgCO_2$/tree/y to $99.1kgCO_2$/tree/y and L. tulipifera was the greatest, followed by glyptostroboides and P. occidentalis, and P. densiflora was the lowest. Total annual $CO_2$ uptake by all street trees in Gyeonggi-do, estimated based on the annual $CO_2$ uptake by each species, was as small as approximately 0.67% of that by forest in Gyeonggi-do. However, urban trees are still important because forest area continues to decrease and urbanization occurs annually in Gyeonggi-do, and should be managed considering their multi-functional aspects, including mitigation of heat island effect and building energy saving(indirect $CO_2$ uptake).

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.3
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• pp.596-606
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• 2015

Recently, the government is promoting the new renewable energy spread and expansion policy. To this end, the investment and the research is ongoing on the core of the ESS (Energy Storage System) for the Smart Grid that is being spread around the industrialized countries. US and European countries have also conducted a variety of ESS related systems maintenance and improvement in order to induce the activation of the ESS industry. On the other hand, our country has no law and institutional foundation for the introduction of activation ESS, and there is no objective basis for the economic impact of the introduction of the ESS. Therefore, spread and activation of the ESS is not properly conducted. In this paper, the economics of the ESS based on the Korea electric pricing system for the spread and activation of the ESS effectively proposes a technique for analysis. To do this, define the ESS operating model, and propose the best economic analysis method economic analysis comparing each operating model.

• Journal of KIISE:Computing Practices and Letters
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• v.7 no.5
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• pp.402-415
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• 2001

Advantages of flash memories are their shock resistance and fast read speed, which is much faster than that of a HDD. Because of these characteristics, they are increasingly used in the traditional household electric appliance and portable handset and therefore, development of file systems which use them as storage medium is increasingly needed. But they have two problems as storage medium. First, data stored in them cannot be overwritten: it must be erased before new data can be stored. Unfortunately, this erase operation usually takes about one second. Consequently, updating data in flash memories takes long time. In this paper, their problem is solved by using a data update mechanism like LFS(Log-structured File System). Second, their erase operations are restricted. We propose novel cleaning policy in order to increase the life cycle. We implemented FAT file system, which is suitable to small storage medium and solved problems, which usually happen in implementing FAT. We evaluated the performance of sequential writes and random writes on our implemented flash file system.