• Journal of Multimedia Information System
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• v.5 no.3
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• pp.155-162
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• 2018

Nowadays, the tracking technology of Quadrant Detector will become actual by new micro devices. Based on the past filed data of the reception experiment with COMETS satellite, we have studied on new device (AD8302, phase difference detector) was acquired and suspect its abilities. In 1998, we have developed a Quadrant Detector for mobile to track a weak signal from satellite on Ka band of COMETS. The Quadrant Detector is comprised of four dedicated feed components for reception under an environment of Nakagami - Rician fading, and one transmission and reception feed component. We were successful in receiving a 23 GHz beacon signal from ICE transponder of the COMETS and succeeded in tracking the satellite from a moving vehicle at speeds of approximately 10 ~ 20 Km/h on paved roads. In 2018, with new device AD8302, we have verified new QD system and performed a simulation, based on the past filed experiment. This new device shall be improving the tracking abilities from mobile body on the earth to the multimedia satellite.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.2
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• pp.790-794
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• 2012

A output strength is limited according to the frequency used in order to protect other wireless stations from interference caused by radio waves emitted from the low power wireless installations. For receivers, unwanted spurious emission is regulated, and regulations in Korea define that additional spurious emission for receivers in the low power wireless installations under 1GHz should be -54dBm, but no regulations have been established yet for low power wireless installations over 1GHz. It is presently required to set domestic standards for devices over 1GHz on account of the expansion of the communication market and its service.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.1
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• pp.9-15
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• 2010

This paper analyzed the problems of the Korean output regulation in the relevant band through an analytic comparison of the current trend of each country and their standard values concerning electric field strength (technical standard) of weak wireless stations with less than 135kHz. In connection with the standard value of electric field strength of each country, which has been proposed in the registration of the appropriate electric wave, the paper aims to propose the standard value of electric field strength that could actually be introduced for suitable unauthorized wireless devices (weak wireless devices) in Korea. Provided that the Korean standard may be upgraded based on the tolerances of electric field strength proposed m this paper, this is expected to be committed to the distribution and advancement of weak wireless devices; and further it is anticipated to be prepared with competitiveness not only in the Korean communications market, but also in the international communications market.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.854-859
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• 2008

This study describes the aging behavior of soils and its mechanism, which have been reported in the literatures mainly by Mitchell(1986) and Schmertmann(1991). It could be known that aging of soils has both positive and negative effects on mechanical properties of soils. In order to show aging effects on dam behavior, a parametric study was carried out based considering the presence of a weak area within clay core zone of the fill dam. From the comparison of results obtained from numerical analysis and filed investigation, age-softening phenomena occurred within core zone during about 30 years after its completion.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.12
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• pp.2498-2504
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• 2009

This paper compared the output limit value of the Korean weak electric field strength wireless device in the 8.2MHz band with the standard values of foreign countries. Through this, the study confirmed that the Korean regulation was lower by about 10-20dB than those of the USA or Europe. In order to prove this, the study measured outputs by entrusting the 8.2MHz EAS system to two measuring companies. As a result of these measurements, electric field strengths were shown to be $70.6dB{\mu}V/m$ and $68.3dB{\mu}V/m$ respectively, and these values were confirmed to exceed the current Korean standard of $59.8dB{\mu}V/m$. Accordingly, it is deemed necessary to review the specifications of the Korean standard in the 8.2MHz band.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2319-2325
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• 2009

This paper compared the output limits value of the Korean weak electric field strength wireless device in the 58kHz band with the standard values of foreign countries. Through this, the study confirmed that the Korean regulation was lower by about 50dB than those of the USA or Europe. In order to prove this, the study measured outputs by entrusting the 58kHz EAS system to two measuring companies. As a result of these measurements, electric field strengths were shown to be $112dB{\mu}V/m$ and $08dB{\mu}V/m$ respectively, and these values were confirmed to exceed the current Korean standard of $102.7dB{\mu}V/m$. Accordingly, it is deemed necessary to review the specifications of the Korean standard in the 58kHz band.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.25 no.2
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• pp.96-98
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• 2014

Injection laryngoplasty is simple and useful procedure in patient with vocal cord paralysis even under local anesthesia. For approaching vocal cord level, flexibility of neck mobility is required to operate injection laryngoplasty but it is relatively difficult to approach vocal cord in patient who has cervical fixations. Laryngeal mask airway (LMA) can be helpful:We use a LMA (I-gel$^{TM}$) during intubation without neck extension on flat supine position under general anesthesia and have a good operation filed. LMA with swivel connector give surgeons better surgical vision and make insertion of fibroscope easily during operation. Hyaluronic acid injection was done use needle (25 G, 5 cm) via percutaneous cricothyroid space : This procedure can be useful method for patients who suffer from not only weak voice but also dysphagia and aspiration high vagal palsy patient after spine surgery or uncooperative with awake injection laryngoplasty.

• Journal of Applied Reliability
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• v.6 no.1
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• pp.63-91
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• 2006

According to the rapid development of science technologies, a life and development cycle of products are getting shorter and structures and functions become more complex so that the reliability requirement of customers is getting greater for components in the products. However, most domestic mechanical components are manufactured by small and medium-sized companies, who are manufacturing in poor economic and technical condition. Because of this, assessment technologies and equipment to predict and guarantee the reliability are very weak. For this reason, it is the fact that many customers neglect the domestic mechanical components which fail to win the reliability. Korean government has been trying to eliminate the problem by establishing 18 reliability assessment centers in 2000 and performing R-Mark certification promotion and constructions of the foundation for reliability assessment to rebuild the reliability on the domestic components and materials. Korea Institute of Machinery and Materials has been designated as a supervising organization for reliability assessment in the machinery filed for 5 years. In this paper, we would like to introduce effective and systematized 12 steps of reliability substantiation test on mechanical components with know-how we achieved during the period.

• Geomechanics and Engineering
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• v.10 no.6
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• pp.757-774
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• 2016

Soils are usually weak in tension therefore different materials such as geosynthetics are used to address this inadequacy. Worldwide annual consumption of geosynthetics is close to $1000million\;m^2$, and the value of these materials is probably close to US$1500 million. Since the total cost of the construction is at least four or five times the cost of the geosynthetic itself, the impact of these materials on civil engineering construction is very large indeed. Nevertheless, there are several significant problems associated with geosynthetics, such as creep, low modulus of elasticity, and susceptibility to aggressive environment. Carbon fiber reinforced polymer (CFRP) was introduced over two decades ago in the field of structural engineering that can also be used in geotechnical engineering. CFRP has all the benefits associated with geosynthetics and it boasts higher strength, higher modulus, no significant creep and reliability in aggressive environments. In this paper, the performance of a CFRP reinforced retaining wall is investigated using the finite element method. Since the characterization of behavior of soils and interfaces are vital for reliable prediction from the numerical model, soil and interface properties are obtained from comprehensive laboratory tests. Based on the laboratory results for CFRP, backfill soil, and interface data, the finite element model is used to study the behavior of a CFRP reinforced wall. The finite element model was verified based on the results of filed measurements for a reference wall. Then the reference wall simulated by CFRP reinforcements and the results. The results of this investigations showed that the safety factor of CFRP reinforced wall is more and its deformations is less than those for a retaining wall reinforced with ordinary geosynthetics while their construction costs are in similar range.

• The Journal of the Korea Contents Association
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• v.13 no.12
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• pp.715-723
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• 2013

Following the social consensus for the need to stop sexual violence, the government has amended juvenile sex protection laws to impose fees on education practitioners who do not report sexual crimes against women, and amended the 'domestic violence prevention and victim protection laws' (2012. 2) so that the police can investigate on site. However, regardless of these wide efforts, the reality is that sexual crimes against the socially weak do not seem to be dwindling, raising concerns of the effectiveness of such amendments. Generally sexual crimes are hard to prove, and even if reports are filed, most cases are dropped with non-prosecution disposition. Victims are usually limited to women and children and this leads to secondary victims. As this thesis states, developed countries have a more systematic protection methods than our country. Therefore, the purpose of this thesis lies on the construction of public safety infrastructure for the protection of sexual abuse victims (enhancing safety protocols with related organizations, implementing a bill of rights for the victims, prevention-centered police education, amendments to current law) to limit human rights violations and criminal injuries.