• Korean Journal of Construction Engineering and Management
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• v.7 no.1 s.29
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• pp.148-158
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• 2006

Public construction companies have strictly followed a rule that they should not do the works using water such as concrete pouring for the structural frame for a certain period during the winter season. It is usually known that the designated non-working period during the winter causes increase of the project duration and the project cost escalation. The halted work also makes negative effects on national economy because it reduces worker's income. However, the situation would be a lot better if the work for the structural frame is allowed under some conditions. The structural framework done alone without being followed by finish works gives a lot of stresses on the finish works. In this sense, this study examines how the structural framework performed during the winter season affect on the critical path of the finish works. To accomplish the objective of this research, the subnet for the finish works as well as a master network are prepared along with critical paths for a virtual construction site. Using the prepared networks, simulations are carried out to see the effects described above. This study is expected to be used in estimating the construction duration of high-rise apartment housing when the site work for the structural frame should be performed during this period.

• Journal of Environmental Health Sciences
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• v.44 no.3
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• pp.227-237
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• 2018

Objectives: This study was investigated the characteristics of small-scale water works (SWW) in Gyeongnam area and conduct a health risk assessment of water-quality inspection items unfitted for water-quality standards (WQS). Methods: The characteristics of SWW in Gyeongnam province were analyzed using the data of SWW in the last three years (2014~2016) published in National Waterworks Information System. In addition, the health risk assessment for inspection items unfitted for WQS was carried out in four steps: hazard identification, dose-response assessment, exposure assessment, and risk characterization. Results: The total number of SWW in Gyeongnam area was gradually decreased from 2014 to 2016. In addition, drinking water sources of SWW were in the order of ground water, valley water, spring water, surface water, and river-bed water. The number of points unfitted for WQS in SWW by year was 22, 45, and 18 in 2014, 2015, and 2016, respectively, and a total of 112 points were found to unfit for WQS in SWW during 2014~2016. The hazard quotient (HQ) for fluoride, nitrate nitrogen, boron in the unfitted points for WQS was more than 1.0, and the mean values for turbidity and color in points unfitted for WQS were 2.38 nephelometric turbidity unit and 16.25 color unit, respectively. Conclusions: The HQ for fluorine, nitrate nitrogen and boron was more than 1.0 in points unfitted for WQS among SWW in Gyeongnam area, and the turbidity and the color degree exceeded WQS, which mean that there is a possibility of harmful impacts on the human health.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.4
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• pp.493-502
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• 2015

In accordance with the Watershed Sewer System Maintenance Plan enforced on February 2, 2013, the different compliance concentration of effluent limit be applied to effluent discharged from public sewage treatment works(PSTWs) in each watershed on the basis of water quality thereof. With the introduction of watershed sewer system, it is necessary to set the compliance concentration of effluent limit for PSTWs situated in the watershed, by region and PSTW size, to achieve water quality criteria for regional watersheds or target water quality under TMDL program. Watershed Environmental Agencies establish the Watershed Sewer System Maintenance Plan and set the compliance concentrations of effluent limit for PSTWs under the plan. The agencies plan to apply tougher effluent BOD concentration limits in Class I to IV areas. Effluent BOD concentration limits will be toughened from 5~10 mg/L to 3 mg/L in class II~III areas, from 10mg/L to 5mg/L in class IV areas. Uniform application of effluent BOD concentration limits to PSTWs in the watershed sewer system need to be complemented considering type of sewage treatment technology employed and watershed characteristics. Therefore, this study presents method to determine the compliance concentration of effluent limit from PSTWs in the watershed.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.4
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• pp.427-440
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• 2016

Various kinds of processes are used in the Public Sewage Treatment Works(PSTWs) in order to achieve water quality criteria and TMDL in the watershed. The performance of the existing processes at PSTWs depends on influent characteristics, effluent quality target, amount of sludge production, power cost and other factors. In present, the Selection Guideline for the Available Treatment Process of PSTWs is used for a process decision in the country. But there are some problems regarding redundancy of assessment factors and complexity of assessment procedure in the guideline. In this study, we did a test application of AHP for process selection of PSTWs, which propose is to simplify assessment factors such as pollutant removal amount, sludge generation, electricity consumption, stability of operation, convenience of maintenance, easiness of existing process application, installation cost, and operating cost concerning of environmental factors, technical factors and economical factors. According to the study, the PSTWs selection procedure guideline can be improved using application of AHP method.

• Journal of the Korean Society for Library and Information Science
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• v.49 no.4
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• pp.265-288
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• 2015

This study analyzed the contracts for library remuneration, amount of the remuneration, average amount of the remuneration in relation to kinds of libraries, distribution of the remuneration, and types and publication year of the works to be collected remuneration based on the data during 2004~2014 from the KORRA. As results, current library remuneration system has limitations for libraries to digitize and transmit to the public their collections, Also, there are some limitations to the protection for copyright holders because the amount of the remuneration collected from libraries has declined and non distribution remuneration has been so high. This study suggested that the library remuneration system needs to be revised considering the scope of library materials to be digitized and predicted frequency of use. Also, the better practical solution to protect copyright holders is not a raise of the library remuneration but the efficient use of the non distribution remuneration.

• Journal of Fashion Business
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• v.23 no.2
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• pp.124-139
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• 2019

The purpose of this study was to examine the characteristic expression of Korean traditional costumes shown in the Korean paintings by Kim Hyun-Jung. The study analyzed the paintings by Kim Hyun-Jung to find out the characteristics of the contemporary Korean paintings and the expression of Korean traditional costumes. The characteristics of Kim Hyun-Jung's works are as follows: 1) The paintings are drawn by using Korean traditional painting methods and finished with Korean traditional paper, hanji. Moreover, they show the Korean traditional costume as main subject material. 2) They use modern painting methods, such as collage, and show pop art characters by use of contemporary popular products. 3) The artist communicates with the public through SNS and YouTube, and shows characteristics of popular art through commercial art products and advertisements. The characteristics of the Korean traditional costume in Kim Hyun-Jung's works are as follows. 1) The hanbok shown in the paintings is a traditional style with tight jeogori and wide chima. Chima is drawn in thin coloring with Korean ink and jeogori is expressed with semi-transparent hanji in various patterns and colors, which shows the subject 'coy'. 2) Various kinds of Korean traditional accessories and modernized flower shoes with high heels are shown as subject materials. The art works by contemporary Korean artists are expected to be the route to give valuable information to the public about Korean traditional costumes as well as the trendy Korean culture.

• Explosives and Blasting
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• v.20 no.3
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• pp.83-96
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• 2002

Reconstruction and redevelopment of old and dilapidated apartment and housing have been increasing to provide more housing accommodation and to secure the safety of building structures since the middle of 1990's. Since, however, little researches on the demolition technique have been made, conventional mechanical demolition method were applied to the most of works that resulted in flooding in small demolition companies. Problems associated with mechanical demolition method are increase not only in working days and costs, but also in public claims, particularly for high-rise building structures. This is to contribute the demolition industries bt providing the concept, standards, and technique of demolition engineering while maximizing working efficiency and minimizing public claims.

• Journal of information and communication convergence engineering
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• v.12 no.3
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• pp.145-153
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• 2014

The improvements of embedded processors make future technologies including wireless sensor network and internet of things feasible. These applications firstly gather information from target field through wireless network. However, this networking process is highly vulnerable to malicious attacks including eavesdropping and forgery. In order to ensure secure and robust networking, information should be kept in secret with cryptography. Well known approach is public key cryptography and this algorithm consists of finite field arithmetic. There are many works considering high speed finite field arithmetic. One of the famous approach is Montgomery multiplication. In this study, we investigated Montgomery multiplication for public key cryptography on embedded microprocessors. This paper includes helpful information on Montgomery multiplication implementation methods and techniques for various target devices including 8-bit and 16-bit microprocessors. Further, we expect that the results reported in this paper will become part of a reference book for advanced Montgomery multiplication methods for future researchers.

• Journal of Korean Society of Water and Wastewater
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• v.17 no.4
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• pp.510-518
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• 2003

The fluoride work management of water supply conveyance has been recommending by the WHO to prevent of tooth decay. Fluoridation of public water supplies has been practiced since 1945. The present approximately 67 countries reported community water fluoridation benefiting many cities. At our country, Fluoridation began in 1981 in Chongiu and Jinhea. In 2002, approximately 40 cities have large populations consuming fluoridated water. But Chongiu stopped fluoridation water works. Few public health measures have been accorded greater clinical and laboratory research, epidemiological study, clinical trials, and public attention than has water fluoridation. In this study, chemical analysis of Sodium Silicofluoride and Fluoride Feed Equipment analyzed. And this study proposed to Fluoride concentration experimental (lab. and field exp.), economics analysis, prevention effect. This study can be decided on the concentration of fluoride injection in Water Fluoridation. Hereafter, this study will be useful in safety and economics of Water Fluoridation in the future.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.41-42
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• 2022

This study analyzed the process related to the linkage between on-site work targeting the middle size Precast Concrete(PC) public apartment building with beam-column system and prepared on-site works flow relationship diagram in which the wet process consists of core Critical Path(CP) to prepare a network diagram of the Precedence Diagram Method(PDM). Through this study, it is expected that it will be possible to maximize the project management capability by suggesting a method to minimize risk factors and the optimized process management of the beam-column system PC public apartment building.