• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.6B
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• pp.1136-1142
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• 2000

In this paper, we present a construction for binary sequences {s(t)} of period N= \ulcorner-1 for an odd prime \ulcornerbased on the polynomial (z+1)d+az d +b, and discuss them in some cases of parameters p, m, d, a and b. We show that new sequences from our construction are balanced or almost balanced, and have optimal three-level autocorrelation. We also derive the distribution of autocorrelation values they take on. The sequences satisfy constant-on-the-coset property, and we will show that there are more than one characteristic phases with constant-on-the-coset property. Some other interesting properties of these sequences will be presented. Results of an extensive computer search are summarized.

• Economic and Environmental Geology
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• v.24 no.3
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• pp.309-318
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• 1991

Analysis for landslides was studied in framework of Chungju dam right abutment, 6.5km northeast of Chungju city. $5.5{\times}10^6m^3$ landslide materials were excavated during dam construction for safety of the Chungju dam. Geology of study area is composed mainly of meta sediments such as dolomitic limestone, quartzite and schist which are dipping toward the Nam Han river. Scanline survey of discontinuities was performed for slope stability, resistivity exploration was performed for the evaluation of potential failure plane, and direct shear strength test of rocks and soils was performed for the effect on landslide. Monitoring systems of tiltmeter, tensiometer, ground water observation hole and level monument were installed during dam construction and interpreted for the evaluation of slope instability. Kinematic solution of the geological structure and evaluation using safety factor for slope may prove the failure of the slope.

• Journal of Drive and Control
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• v.10 no.4
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• pp.7-13
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• 2013

A tractor is a farm vehicle that is designed to provide a high tractive effort at low speed. It is used for versatile agricultural tasks such as hauling a trailer, tillage, mowing and construction work. As the intensity of work increases, tractors equipped with automatic transmission become popular due to the work convenience. Though manual and power shuttle transmissions are produced by domestic corporations, development for full-automatic power shift transmissions has never been challenged, and so related technology level is quite low. This paper gives a survey of the automatic transmissions from advanced foreign company, which includes layout of gear train, the way hydraulics controls clutches and brakes, electronic control system. The results are expected to be utilized as a basis in the development of original power train design for tractor.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.160-161
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• 2019

Recently, a bed company's product has detected a certain level of radon or higher, making it a popular search word on portal sites. Because of this problem, people are becoming more interested in radon. The government plans to support the establishment of a radon alert system for households through a radon concentration survey of 10,000 households. The use of palm charcoal as an indoor finishing material will reduce the risk of lung cancer through radon reduction. The experiment used a method of replacing palm activated carbon with blast furnace slag, and the adsorption performance of radon tends to increase as the replacement rate of palm activated carbon increases.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.23-24
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• 2019

In this paper, the compressive strength characteristics of cement paste were compared with the addition of liquefied red mud with the addition of nitric acid in order to improve the strength of the deteriorated cement. The results showed that the compressive strength with between 7 days and 28 days was greater than that of liquefied red mud. The ratio of daily compressive strength of the liquefied red mud is higher than that of the Plain with a 1 percent addition rate, and the ratio of compressive strength is lower than that of the Plain on the 28 days. Therefore, the compressive strength of neutralization liquefied red mud compared to liquidated red mud was relatively high, and the compressive strength of the red mud was shown to be improved to a level almost similar to that of Plain.

• Journal of Information Science Theory and Practice
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• v.9 no.3
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• pp.1-13
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• 2021

In the current smart device-based information environment, information utilization is closely related to social capital. Additionally, the smart divide that occurs owing to the differences in use of smart devices has a significant influence on social capital. In this respect, this research empirically analyzed how the smart divide affects social capital construction. The study found that the level of and proficiency in using smart devices and diversity of the information formats used through smart devices affect social capital construction. Further, people who fully utilize smart devices can enhance their participation in social activities, social networks, and reciprocal activities, leading people to construct social capital in a wider range. Contrarily, those who are unable to use smart devices adequately may be disadvantaged in terms of the opportunity to construct social capital and share public interests. Thus, to maximize the intrinsic value of social capital, it is necessary to consider the factors of the smart divide as a complicated and multi-faceted digital divide and the ways to utilize social capital as a driving force for integrating society, and not as a mechanism for dividing members of society.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.85-86
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• 2019

In this study, when the normal concrete became a $20^{\circ}C$ image after the exposure time at an external temperature of $-15^{\circ}C$, the limit point of the early frost damage was analyzed. As a result, it was confirmed that the degree of concretion was higher than the external level after carrying in and after exposure, and that the initial Tokai damage was observed after 12 hours of exposure.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.226-227
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• 2019

Installation and usage methods are currently different between China and Korea for the same rubber asphalt waterproofing sealant. Quality verification is not properly carried out in this situation, so it is necessary to secure reliability in order to export domestic materials to China. In this study, rubber asphalt waterproofing sealant used as injection-type leakage repair material was tested in accordance to adhesion strength quality test method outlined in the JC/T2428 Chinese Industrial Standard to confirm the basic performance is compliant or not.

• Journal of KIBIM
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• v.11 no.2
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• pp.17-23
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• 2021

BIM (Building Information Model/Modeling) is attracting attention not only as a unit technology, but also as a factor that can promote the transformation of the entire construction industry process. This study aims to investigate the status and cases of policy introduction and legalization of BIM in foreign countries for the advancement of their own construction industry, and to discover policy implications that can be applied to Korea. The first survey uncovered policy elements, and based on this, the second survey conducted an in-depth survey of experts in actual BIM service and research activities. Looking at each priority, BIM standardization, mandating BIM in projects, payment standard establishment, and PQ additional points were given the highest level of importance.

• Journal of the Korea Safety Management & Science
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• v.24 no.3
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• pp.39-46
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• 2022

This study has found the socio-economic factors that affect occupational accidents and measured the influence quantitatively. We built the panel data of 4 countries (Japan, Germany, the U.S., and the U.K.) and the analysis model counted on the fixed effect model to reflect the countries' differences. The fatal occupational injury rates in the analyzed countries had a statistically significant relationship with the level of per capita GDP, the proportion of the construction industry, the rate of male workers, annual average working hours, the rate of workers in manufacturing and construction industries, etc. The annual average working hours have a positive correlation with the fatal occupational injury rate. To reduce occupational accidents effectively, we should be monitoring and researching various factors that can affect the occurrence of occupational accidents such as worker characteristics, changing industrial structure, and changes in working hours.