• Journal of the Korean Geotechnical Society
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• v.24 no.7
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• pp.25-36
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• 2008

The plane strain test can reproduce the real field condition and failure behavior precisely over other laboratory shear tests. Accordingly, this test has been utilized to investigate the shearing behaviors associated with overall failure behavior and local deformation of soils. However, most plane strain tests have been carried out with restrained end plates due to difficulties in manufacturing the equipment and also performing it. This restraint induces different results with real field because of shear stress on end plates. In this study, plane strain tests with/without bottom plate restraint were performed on Jumunjin-sand. The measurement of overall and local deformation was accomplished by digital image correlation technique as well as external LVDT. By applying digital image correlation method using two consecutive images captured through the transparent wall, local deformation behavior of various parts inside the specimen was estimated. And the formation and development of shear band caused by the restrained effect of end plate and the deformation mechanism of sand under plane strain condition were examined.

• Electronics and Telecommunications Trends
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• v.35 no.6
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• pp.107-118
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• 2020

The smart city agenda aims to solve various problems arising in cities and promote the welfare and happiness of citizens by utilizing the new technologies of the 4th Industrial Revolution. Smart city policies have been promoted at the national level, but until now, policy implementations have not been effective enough to fundamentally affect citizens. To realize a more realistic and practical smart city, it is necessary to examine the problems occurring in the city in depth and set the direction and tasks of the smart city accordingly. Therefore, this study specifies the issues and problems faced in 12 sectors, including manufacturing, logistics, medical care, and safety. Next, by referring to the existing literature, a future smart city integration model is proposed that can respond to these problems. That is, future smart cities should create detailed services with enhanced efficiency, sustainability, strong risk management, safety, and satisfaction as the main goals. This study is meaningful in that it suggests a vision and tasks of smart cities that can solve problems in various sectors in a form that can be felt by the citizens.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.1
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• pp.130-136
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• 2020

There are many problems that occur currently in agriculture industries. The problems such as unexpected of changing weather condition, lack of labor, dry soil were some of the reasons that may cause the growth of the plants. Condition of the weather in local area is inconsistent due to the global warming effect thus affecting the production of the crops. Furthermore, the loss of farm labor to urban manufacturing jobs is also the problem in this industry. Besides, the condition for the plant like air humidity, air temperature, air quality index, and soil moisture are not being recorded automatically which is more reason for the need of implementation system to monitor the data for future research and development of agriculture industry. As of this, we aim to provide a solution by developing IoT-based platform along with the irrigation for increasing crop quality and productivity in agriculture field. We aim to develop a smart garden system environment which the system is able to auto-monitoring the humidity and temperature of surroundings, air quality and soil moisture. The system also has the capability of automating the irrigation process by analyzing the moisture of soil and the climate condition (like raining). Besides, we aim to develop user-friendly system interface to monitor the data collected from the respective sensor. We adopt an open source hardware to implementation and evaluate this research.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.344-345
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• 2011

A necessity to a superconducting cable in power transmission systems have been growing more and more due to high power density in urban areas and rapid increase of power demand. In view of these situation, it is a noteworthy fact that superconducting cable has remarkable advantages, such as lower power loss and 3-5 times higher power transmission capacity, compared with conventional power cable. For the last a few years, long-term reliability tests had been carried out in the KEPCO PT Center, and now it has been installed in KEPCO's real power grid for demonstrating commercial operation. This paper deals with the test results of dielectric properties performed at manufacturing factory for the joint box, termination and core of HTS cable system and whole system connected in real power grid.

• Korean Journal of Construction Engineering and Management
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• v.5 no.1 s.17
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• pp.80-87
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• 2004

This paper presents an analysis of construction project management from supply chain management perspective to gain insight from all constituents and to identify areas of improvement. In order to suggest opportunities for improvement, interviews with the members of a typical urban office building project in US were held. Based on that, a qualitative analysis of construction projects is presented. Focusing on electrical and mechanical sub-systems, this study illustrates the roles of subcontractors, suppliers, distributors, and manufacturing representatives as well as the complexity that a general contractor fares in managing its supply chain. The author$^{\circ}\phi$s recommendations are focused on process restructuring and automation, which include some quantifiable performance measures, incentives, and their alignment with each other

• Journal of the Korean Society of Food Culture
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• v.13 no.2
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• pp.119-126
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• 1998

This study was carried out to give some help for housewives recognizing the desirable purchase of processed foods and food additives. This results were abtained as follows; In case of purchase action for processed foods of housewives confirmation of manufacturing date was the highest point(4.62). When housewives bought processed foods they considered the taste of them as first, and frequencies of processed foods intake showed the ratio of 46.6%, also it was shown to be used once a week. The order for use of processed foods were milk, milk products(butter, cheese, yoghurt, lactic bacterium beverage) 40.2% >canned foods 22.6% >meat products(ham, sausage, bacon) 20.9% > jelled fish 16.3%. Most of housewives wanted to have the knowledge and information for food additives at the highest point(4.11). The interest about food additives of housewives was shown to the order of synthetic preservative 3.86 >chemical seasoning 3.74 >synthetic sweetener 3.59 >synthetic coloring agent 3.53. Also, it was shown to be thought that the hazard factors effected on food safety were agricultural chemical residue(30.9%), environmental pollution(25.2, food additives(23.0%), and microorganism contamination(20.9%).

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.2
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• pp.166-173
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• 2002

The wheel bearing hub unit is developed type of wheel bearing unified with the hub parts. It has advantage of reducing the weight and the number of components. And, it also improves uniformity of manufacturing quality, In order to design the wheel bearing hub units, many techniques are used such as load analysis, structure analysis and bearing characteristics analysis and so forth. These techniques need highly accurate load conditions founded on service conditions. In this study, to design the wheel bearing hub units used widespread in passenger cars, the service load was measured through driving tests on the public roads and in the special events. The public roads are classified into highway, intercity road, rural road, urban road, and unpaved road so as to know what the characteristics of the road loads are. The results of the tests showed that the wheel force was relative to the lateral acceleration, and also could be calculated from the lateral acceleration. The lateral acceleration was measured from 0.0G to 0.6G in general driving on the public roads, with different distributions in each road type. In special events, the maximum lateral acceleration was measured from 0.8G to 1.3G.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.05a
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• pp.107-110
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• 2006

In this study, recently it is urgently required that recycle promotion of construction and demolition waste concrete because urban development is accelerated and redevelopment project is rapidly expanded, production quantity of construction and demolition waste concrete is being increased. On the other hand, it is urgently required that problem solution of demand and supply unbalance of fine aggregate because the sea sand is restricted by exhaustion of river sand and intensification of environment influence evaluation. Therefore, it tries to conform in time necessity, there is the objective of this study to provide the fundamental data about the re-application as the comparison and analysis the quality present condition for the recycled fine aggregate in the inside and outside of the country. At the same time it will be able to improve the quality of the recycled fine aggregate waste as investigating the physical nature and a quality present condition of the recycled fine aggregate from construction waste.

• Land and Housing Review
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• v.10 no.3
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• pp.77-87
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• 2019

In Korea, the modular construction method was applied to the construction of facilities such as military barracks and school dormitories, beginning with the pilot project of Seoul New Elementary School in 2003. In 2017, public modular houses were supplied to Busan(Yongho-dong) and Seoul(Gayang-dong), and modular housing is expected to continue to be supplied in the future. However, there is no clear construction standard for the modular housing construction yet, and there are few cases where the infill modular system is applied. Therefore, this study established the work breakdown structure and proposed a standard process focusing on the infill modular system applied to the construction of Dujeong-dong modular house in Cheonan. Level 1 of the work breakdown structure by construction stage of Infill modular was defined as modular manufacturing, assembly, and finishing process. Level 2 was defined as preparation, modular production, modular infill, modular fixing, floor plastering, building finishing, and other site finishing. Level 3 is defined as 57 detailed unit work of infill modular construction. The standard process of infill modular is proposed for the assembly stage that is commonly applicable to infill modular housing construction. The results of this study can be used for the process plan, transportation plan, lifting plan of modular housing construction.

• Journal of the Korea Furniture Society
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• v.23 no.4
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• pp.381-387
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• 2012

Utilization of underground floor is becoming the main issue of our society to maximize and diversify the potential of recent urban space. It has brought about the changes of underground floor. Recently there are lots of huge bookstores in these underground floor. Bleach, adhesive and ink used for manufacturing books pollute indoor air in bookstore. Therefore, the purpose of this study is to analyze indoor air quality in these large bookstores. Concentrations of carbon dioxide and formaldehyde in three large bookstores in Seoul were measured by presence and type of books and distance of main entrance which is well-ventilated. According to the data, space that places lots of volumes measured higher concentration of formaldehyde than that of non-existence books. Children's book section was measured more concentration of formaldehyde than other book section. Closer main entrance near outside, lower concentration of formaldehyde was measured. Concentration of carbon dioxide was affected by the number of people in bookstore.