• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.3-4
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• 2000

본 논문에서는 다양한 QoS와 전송률을 갖는 WCDMA 시스템에 복합간섭제거기법을 적용하여 그 성능을 분석하였다. 전송률이 높은 사용자들은 병렬간섭제거기법이나 복합간섭제거기법을 사용하여 간섭을 제거하는 것이 효과적이며, 전송률이 낮은 사용자들은 순차간섭제거기법이나 복합간섭제거기법을 사용하는 게 효과적이다. 그러나, 순차 및 병렬간섭제거기법과 비교해 본 결과 QoS와 전송률에 관계없이 복합간섭제거기법의 성능이 가장 우수함을 알 수 있었다.

• The Journal of the Korea Contents Association
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• v.18 no.5
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• pp.330-342
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• 2018

The purpose of this study was to investigate effects of abuse, neglect, and excessive interference of parents on adolescent aggression in the longitudinal context and examine the moderating effect of playing computer game theoretically guided by the flow theory. 2,351 adolescents from the Korean Children & Youth Panel Survey was analyzed using Linear Mixed Effects Regression procedures. Primary findings are as follows: (1) adolescents with higher level of abuse or excessive interference showed higher level of aggression. (2) the aggression level of adolescents with higher level of abuse or excessive interference consistently decreased over time. (3) the link between abuse and aggression was significantly moderated by playing computer game. In conclusion, the negative effect of the abuse on adolescent aggression could be significantly decreased by playing computer game.

• Information and Communications Magazine
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• v.16 no.4
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• pp.68-74
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• 1999

본 논문에서는 최근 IMT-2000을 위한 무선 전송 규격에 반영된 SK 텔레콤의 기술을 설명한다. SK 텔레콤에서는 역방향 다중 접속에 의한 간섭량을 줄이기 위한 기술로서 기지국에서 이동국의 송신 타이밍을 조절하는 '역방향 동기식 전송방식(RSTS : Reverse link Synchronous Transmission Scheme)'을 ITU에 제안하여 현재 W-CDMA의 표준으로 채택되었다. 또한 기지국간 비동기 방식에서 셀 탐색을 위한 방법으로 '클러스터 파일럿과 셀파일럿을 이용한 다단계 셀 탐색 방법'을 제안하여 W-CDMA의 다단게 셀 탐색 방법의 기본 개념을 제시한 바 있다. 본 논문에서는 국제 표준에 반영된이 두가지 방법에 대한 알고리즘을 설명하고 동기식 전송 방식으로 얻게 되는 역방향 다중 접속 간섭량의 감소를 시물레이션을 통해 보인다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.2
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• pp.159-164
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• 2005

When an optical pulse propagates through the atmospheric channel, the atmospheric turbulence attenuates and spreads this pulse. This attenuation and broadening of pulse are occurred by the fluctuation in the arrival time of pulse at the optical receiver. This pulse broadening induces the intersymbol interference (ISI) between the adjacent pulses. finally, the adjacent pulses are overlapped and the bit rate and the repeaterless transmission length are limited by the ISI. In digital communication system, therefore, the pulse broadening is more important factor than the attenuation. In this paper, thus, we find the ISI in the atmospheric turbulence as the function of the structure constant for the refractive index fluctuation that presents the strength of turbulence using the temporal momentum function and present it by numerical analysis.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1027-1032
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• 2003

Thermo-mechanical behavior of flip-chip plastic ball grid array (FC-PBGA) packages are characterized by high sensitive $Moir{\acute{e}}$ interferometry. $Moir{\acute{e}}$ fringe patterns are recorded and analyzed for several temperatures. Deformation analysis of bending displacements of the packages and average strains in the solder balls for a single-sided package assembly and a double-sided package assembly are presented. The bending displacement of the double-sided package assembly is smaller than that of the single-sided one. The largest of effective strain occurred in the solder ball located at the edge of the chip and its magnitude of the double-sided package assembly is greater than that of single-sided one.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.6
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• pp.128-134
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• 1997

Holographic interferometry is a useful whole-field nondestructive tesing method for measuring deformations and vibrations of engineering structure. In practical way most holographic interferometer uses a diverging beam, a point light source. When an oject is relatively small, the optical arrangement using a collimated light source has no difficulty technically but for a large object the collimated beam connot be applied anymore practically. In this paper we calculate the error of measured displacement from the sensi- tivity vector dominated by the geometry of optical arrangement for holographic interferometer and show the result with 2-D plots. A plane surface and a cylindrical surface were chosen as objects to be measured and the results from the cases of a diverging and a collimated beams were compared and analyzed.

• Journal of the Korean Vacuum Society
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• v.14 no.3
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• pp.103-109
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• 2005

A new medium vacuum primary standard using the static expansion method was developed in KRISS. In order to evaluate the performance of the equipment, we compared the medium vacuum standard with an ultrasonic interferometer manometer using two capacitance diaphragm gauges, the measuring ranges of which were 133 Pa and 1,333 Pa respectively. The result, Error normalized values, showed that the two standards are coincident each other within the range of combined uncertainty at calibrated pressure of $3pa\;\sim\;100pa$.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.3
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• pp.484-490
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• 2016

Full-duplex communication can enhance wireless capacity by enabling simultaneous transmission and reception of the signals on the same frequency spectrum. Such a benefit, however, is only achieved when strong self-interference is well canceled below a sufficient level. To achieve this goal, there have been several approaches for cancellation, each of which is combined with digital-domain cancellation for a higher gain. In this paper, we implement two self-interference cancellation techniques and integrate them with a software defined radio-based wireless communication testbed. Two cancellation techniques (antenna cancellation and noise subtraction) are implemented and the cancellation gain is measured via real experiments. The results show that the gain of the antenna placement technique highly depends on the placement of a receiving antenna and the highest gain is achieved at the expected point, and we show that combining the noise subtraction circuit with the antenna placement further improves the cancellation gain.

• Journal of Internet Computing and Services
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• v.7 no.3
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• pp.31-39
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• 2006

Ubiquitous and pervasive environment presents opportunities for a rich set of location aware applications such as car navigation and intelligent robots, interactive virtual games, logistics service, asset tracking etc. Typical indoor location systems require better accuracy than what current outdoor location systems provide, Outdoor location technologies such as GPS have poor indoor performance because of the harsh nature of indoor environments, In this paper we present a novel reducing interference location system that is particularly well suited to support context aware computing. The system, called EEM (Enhance Envelop Method) alms to combine the advantages of real time tracking systems that implement distributed environment with the suitability of infrastructure sensor network.

• Korean Journal of Clinical Laboratory Science
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• v.56 no.2
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• pp.171-180
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• 2024

The endotoxin test is based on the reaction between Limulus Amebocyte Lysate (LAL) and the lipopolysaccharides of Gram-negative bacteria. In this study, we sought to identify factors that interfere with the LAL testing of radiopharmaceuticals and evaluated acceptable ranges. A gel-clot LAL test and a chromogenic LAL test were used as endotoxin tests. We compared the performances of the Endosafe^Ⓡ LAL and recombinant Endosafe^Ⓡ Recombinant Cascade Reagent (rCR) cartridges for the chromogenic test. The factors that interfered with ⁶⁸Ga-DOTATOC injection were pH, 4-(2-hydroxyethyl) piperazine-1-ethanesulfonic acid (HEPES) buffer, and organic solvents, especially ethanol. However, interference by these factors was overcome by diluting the ⁶⁸Ga-DOTATOC injection tenfold. In addition, no interference was observed at pH values between 4 and 8, at a HEPES concentration of 2,000 ㎍/mL, or an ethanol concentration of <1%. Furthermore, results showed that interfering factors had similar effects on the performances of the Endosafe^Ⓡ LAL and Endosafe^Ⓡ rCR cartridges. The results of this study are expected to be useful for evaluating factors that interfere with the endotoxin testing of new radiopharmaceuticals.