• Journal of the Korea Safety Management & Science
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• v.7 no.3
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• pp.29-36
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• 2005

This research has been conducted in order to assess the effects on quality management factor of the construction sites. 30 companies abiding by the 'construction industry law' and 32 companies abiding by the 'housing construction promotion law' have been researched in areas of quality-management environment, quality-management understanding, quality-management education on construction field, quality-system and quality-improvement. This construction quality factors are to realized the anticipated results not only quality level's increasing, but also company's confidence, competitiveness. We were able to obtain participations of 62 questionnaire, and derived statistics by means of SPSS/PC version 10.0. In this study, we find the bottleneck factor for promotion and upgrade quality management factor of the construction sites and suggest a way out of difficulties.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.1289-1292
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• 2006

The demand on a turnout layed on a bridge is rising owing to the increasing number of stations on the viaduct. And also the demand on a turnout with CWR is rising to upgrade running speed of the passing train. A CWR connected with turnout is subjected to additional axial force induced by the actions due to change in temperature, braking and starting force, and bending of the deck. But magnitude and distribution of the axial force in rails of turnout is not clear yet. So, in this study, a field measurement was conducted to know them. The strain gage method was adopted for field test. The FBG sensor for the strain measurement was used to ensure stability of test value and durability of gage for long term. It is expected that we can get data on the axial force in rail connected with turnout with respect to seasonal temperature change by the established field test system.

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.202-203
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• 2007

Induction Motor is important at tilting train. Tiling train induction motor should be operated to commercial servicespeed 180km/h at Korea Conventional Line upgrade railroad. As the induction motors are without commutators, maintenance is easy and it is far lighter than the conventional motors with the same capacity. The induction motor, however, posed problems in use as its motor torque is not large enough compared with DC motors. With the recent advances in power semiconductors, it is possible to apply the induction motors to trains by applying VVVF inverter control method to the traction motor. In this study, we realize the stable measurement AC motor temperature characteristic of TTX train.

• Journal of the Optical Society of Korea
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• v.12 no.4
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• pp.226-231
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• 2008

40 Gbps WDM Systems using super-Gaussian RZ pulses have been studied by numerical simulation to optimize their performance. The assumption of standard single mode fiber is valid when existing WDM systems are required to upgrade their performance to 40Gbps. It is shown that the standard single mode fiber can transmit optical signals over 720 km (Q > 10) by optimizing optical and electrical filter characteristics at the receiver and by compensation of dispersion. However, it is also shown that ${\pm}0.3%$ dispersion compensation tolerance per span (80 km) could prohibit transmitting over 320km (Q > 10). In addition, a duty cycle of less than 0.4 degrades system performance significantly.

• Journal of Positioning, Navigation, and Timing
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• v.8 no.1
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• pp.1-12
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• 2019

In this paper, we implement a navigation software of a Global Navigation Satellite System (GNSS) receiver based on a commercial purpose GNSS software receiver platform and verify its performance by performing experimental tests for various GNSS signals available in Korea region. The SX3, employed in this paper, is composed of an application program and a Radio Frequency (RF) frontend, and can capture and process multi-constellation and multi-frequency GNSS signals. All the signal processing procedure of SX3 is accessible by the receiver software designer. In particular for an easy research and development, the Application Programing Interface (API) of the SX3 has a flexible architecture to upgrade or change the existing software program, equipped with a real-time monitoring function to monitor all the API executions. Users can easily apply and experiment with the developed algorithms using a form of Dynamic Link Library (DLL) files. Thus, by utilizing this flexible architecture, the cost and effort to develop a GNSS receiver can be greatly reduced.

• International Journal of Internet, Broadcasting and Communication
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• v.11 no.2
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• pp.50-58
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• 2019

The clear and specific objective of this study is to design a false news discriminator algorithm for news articles transmitted on a text-based basis and an architecture that builds it into a system (H/W configuration with Hadoop-based in-memory technology, Deep Learning S/W design for bigdata and SNS linkage). Based on learning data on actual news, the government will submit advanced "fake news" test data as a result and complete theoretical research based on it. The need for research proposed by this study is social cost paid by rumors (including malicious comments) and rumors (written false news) due to the flood of fake news, false reports, rumors and stabbings, among other social challenges. In addition, fake news can distort normal communication channels, undermine human mutual trust, and reduce social capital at the same time. The final purpose of the study is to upgrade the study to a topic that is difficult to distinguish between false and exaggerated, fake and hypocrisy, sincere and false, fraud and error, truth and false.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.621-626
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• 2005

Recent increases in construction costs on Korean public works projects, largely due to change orders caused by poorly elaborated design, become a motivation of applying VE process in Korean construction industry. The Seoul Toll Plaza project, recently value analyzed by four VE teams, demonstrates how value management helps save time, money and increase functional performance. The objective of this project is to upgrade and expand existing pay and ticket booths system on "Kyungboo Express Highway", the main artery for the Korean peninsula linking Seoul to Pusan. The value management study generated several innovate alternatives capable of saving up to 50% of project cost from the baseline project plan.

• Journal of the Korea Society of Computer and Information
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• v.19 no.1
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• pp.77-84
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• 2014

In this paper, we propose the hierarchical network synchronization scheme that is backward compatible for the existing commercial system, efficient for total system performance, and whose hardware modification is minimized. This system performance is, the relationship among bandwidth efficiency, complexity and MODEM performance, and superiority of network system applicability. The proposed structure can remedy the high hardware complexity and the lower accuracy of network sychronization that the existing satellite communication terminal system in the star network based on TDM/MF-TDMA of DVB-S2/RCS standards has. Besides, It has high efficiency in view of cost and system performance if the system designed for satellite broadcast requires system upgrade. In the body section, its hardware complexity and system performance of the proposed algorithm is analysed theoretically and treated with the related parameters(symbol rate, spreading factor, etc.) and the BER performance of control channel through the computer simulation for its verification that it can be applied for communications system.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2007.02a
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• pp.87-96
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• 2007

Ubiquitous is a Latin-derived word meaning "to exist at any time and place" like water or air. In computing, the word "ubiquitous" indicates an environment in which users have access to networks without any limitation regarding computer networks or places. Important issues in building Ubiquitous Korea (U-Korea) are the social problems appearing with a rapid increase in the old age population. Nowadays, with the rise of the nuclear family, the increase in the number of elderly people living alone, and the change in the status of women, both wives and husbands are employed outside the home, and the relatives who would be responsible for supporting the elderly sometimes are on long or short business trips, and it happens that old people can't be looked after. Therefore the government developed a wireless paging system for the sick, disabled, old and weak so that when an emergency happens, by just simply dialing 119, an emergency aid center could take prompt action. However, the present wireless paging systems composing the under-layer of the emergency aid information system have some problems, such as, a lack of reliability, problems among terminals, mobile transmitters and receiving terminals, the users' refusal to admit the need for the system and poor operational skills, administrators' perfunctory management and checks, etc. On account of these problems, the system efficiency has degraded and therefore a system upgrade is necessary. In this paper, we attempt to evaluate the newly implemented SAFE119 system, a new wireless paging system seeking to correct the problems of the current system.

• Journal of Ocean Engineering and Technology
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• v.30 no.4
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• pp.294-302
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• 2016

Because of the importance of steel material saving and rational ship structural design due to the rapid increase in steel prices, a ship structural design system was developed for plate members reinforced by doubler plates subjected to biaxial in-plane compressive loads. This paper mainly emphasizes the design system improvement and upgrade according to the change in the in-plane loading condition of the doubler plate from the single load discussed in a previous paper to the biaxial in-plane compressive load discussed in this paper. A direct design process by a structural designer was added to this developed optimized system to increase the design efficiency and provide a way of directly inserting a designer's decisions into the design system process. As the second stage of preliminary steps of doubler design system development, design formulas subjected to these biaxial loads used in the doubler plate design system were suggested. Based on the introduction of influence coefficients $K_t_c$, $K_t_d$, $K_b_d$ and $K_a_d$ based on the variations in the doubler length, breadth, doubler thickness, and average corrosion thickness of the main plate reinforced by the doubler plate, respectively, the design formulas for the equivalent plate thickness of the main plate reinforced by the doubler plate were also developed, and a hybrid design system using these formulas was suggested for the doubler plate of a ship structure subjected to a biaxial in-plane compressive load. Using this developed design system for a main plate reinforced by a doubler plate was expected to result in a more rational reinforced doubler plate design considering the efficient reinforcement of ship plate members subjected to these biaxial loads. Additionally, a more detail structural analysis through local strength evaluations will be performed to verify the efficiency of the optimum structural design for a plate member reinforced by a doubler plate.