• Proceedings of the Korean Information Science Society Conference
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• 2006.10d
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• pp.34-39
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• 2006

IEEE 802.11e 무선LAN 매체접근제어(MAC) 통신규약의 분산조정함수(DCF)의 성능은 경쟁노드수가 증가할수록 급격히 떨어진다. 이러한 문제점을 해결하기 위해서 채널의 유휴슬롯시간(Idle Time)을 측정해서 최소 경쟁윈도($CW_{min}$)를 조절하는 방식이 제시되었다. 이러한 방식을 각 부류별로 서비스 품질이 보장되는 IEEE 802.11e 네트워크로 확장하여 성능을 최대화하는 기법을 이 논문에서 다루겠다. 각 부류별로 서비스품질은 유지하면서 네트워크 전체의 성능을 높일 수 있는 최적의 경쟁윈도 크기를 찾아내는 기법을 보이도록 하겠다.

• The korean journal of orthodontics
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• v.33 no.3 s.98
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• pp.151-156
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• 2003

To provide some guideline for microscrew implants, 73 patients that received a total of 180 mini- or microscrew implants were scrutinized. The overall success rate was $93.3\%$ (168 among 180 mini- or microscrew implants) and the mean period of utilization was 15.8 months. Microscrew implants in the UB group (maxillary buccal area) succeeded at a rate of $94.6\%$ (87 among 92), mini- or microscrew implants in the LB group (mandibular buccal area) succeeded $96.6\%$ of the time (56 out of 58), while microscrew implants in the UP group (maxillary palatal area) had a $100\%$ success rate (11 out of 11), and mini- or microscrew implants in the LR group (retromolar area) succeeded in $73.7\%$ of cases (14 among 19). This study might indicate that microscrew implants can be used successfully as orthodontic anchorage in daily orthodontic practice.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.2
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• pp.195-201
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• 2022

Hemimandibulectomy and free fibular flap (FFF) in patients with squamous cell carcinoma could disturb the functional movement of the mandible. The muscular function in the sectioned side was compromised because of the incompetency of the muscle attachment to the mandible, leading to the unstable occlusal contact in the centric and eccentric occlusion. In this report, we present a case of a 63-year-old male who underwent cancer surgery and reconstruction with fibular graft, and he needed a fixed dental prosthesis to restore tooth loss in the anterior region. Occlusal contact change and instability were found according to the bite force in the centric relation and eccentric movement. This case report aimed to present the prosthetic procedure for fabricating the functionally optimized fixed prosthesis wherein the functionally generated path (FGP) technique and digital imaging method were applied to replicate mandibular movement and vertical dimension of the patient.

• Journal of Soil and Groundwater Environment
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• v.14 no.4
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• pp.45-53
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• 2009

This study concerned remediation of heavy metal contaminated farmland soils near abandoned mine, using stabilization method, with particular emphasis on the remediating the soils contaminated with multi-elements. In this study, stabilizing heavy metals based on 'In-situ chemical fixation' has been applied to the soil collected from an abandoned mine in Korea, using column test, with various stabilizing agents, including $FeSO_4$, $KMnO_4$, sludge (collected from coal mine drainage treatment pond), zero-valent iron (ZVI), zeolite and $CaCO_3$. Sixty five-days operation of the flow-through columns yield $FeSO_4\;+\;KMnO_4$ and zeolite are efficient on reducing As leaching from the soil. ZVI and sludge are reducing the leaching of Cu. Although $FeSO_4\;+\;KMnO_4$ seem to be efficient for most heavy metals, high pH in the initial stage of test enabled high leaching of the heavy metals, whereas fixation of the heavy metals maintain throughout the rest of the test period, with increasing pH up to around 6. Addition of some alkaline agent may inhibit the low pH during the application. The column test was also run as two set: one set incubated with deionized water for 72 hours prior to starting the test, and the other without incubation. The incubated set demonstrated better stabilizing efficiency, indicating the potential optimized operation method.

• Journal of Music and Human Behavior
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• v.1 no.1
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• pp.11-32
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• 2004

According to Edwin Gordon(1987, 1997, 2003), music aptitude is a product of interaction of innate potential and early environmental experiences. He referred to music aptitude of children up to nine years of age as developmental music aptitude which fluctuates due to musical environment. Music aptitude stabilizes at age nine, and the music aptitude after age nine is called "stabilized music aptitude". This research is to examine Gorden's hypothesis that the younger a child receives music education, the higher music aptitude. Also, this research is to experiment the effect of Audiation activities developed in Audie Music Curriculum on music aptitude. The researcher and another Audie teacher as a co-teacher guided children together for 30 minutes once a week. The pedagogy guidelines for informal guidance in music learning theory were kept throughout the classes. Also, Audie's teaching method which had been developed for Korean Kindergarten educational environment was also applied. Five-year-old subjects in Experimental group 1 experienced the Audie Music Curriculum of one year; five-year-old subjects in Experimental group 2 experienced it for two years. Primary Measures of Music Audiation was administered three times during their last year of Kindergarten. Subjects in the Control groups, one examined at the beginning and the other at the end of their last year in Kindergarten, received no Audie instruction. There was no significant difference in tonal aptitude, but there was significant difference in rhythmic aptitude(p< .05) among the experiemental groups. Because both Experimental groups showed statistical significance (p< .001) in the music aptitude increase during their academic years, the significant differences of the year-end music aptitude between control group and experimental groups were the expected result.