• 전기전자학회논문지
• /
• 제2권2호
• /
• pp.233-238
• /
• 1998

본 논문에서는 G.726 ADPCM 음성방식을 기존의 단일 압축을 대신 16Kbps 와 40Kbps의 두 가지 압축율을 사용한 가변 압축방식에 의한 음성 코딩 방식을 다루었다. 음성의 묵음 또는 소 신호 부분은 음질의 향상보다는 데이터 비트 수를 줄이기 위한 저 전송 16Kbps 압축율을 적용하였고 임계값 이상의 대 신호 부분은 음질을 향상하기 위하여 40Kbps의 압축율을 적용하여 모든 신호를 단일 압축율로 코팅하는 방식에 비하여 전체적으로 압축율을 높여 전송 비트 수를 줄이면서 음질을 저하시키지 않도록 하였다. 분 논문에서는 시뮬레이션을 통하여 여러 가지의 임계값에 의한 가변 압축 코딩 방식에 대하여 압축율과 음질의 관계 를 다루었다. 또한 고정된 임계값에 대하여 입력 음성의 크기를 여러 가지로 변동하여 주변 배경잡음과 포화에 의한 음질의 저하를 고찰하여 가변 율에 의한 음성의 코딩방식에서 임계값과 입력의 크기가 음질 및 압축율에 미치는 영향을 다루었다. 각 시뮬레이션의 경우에 대하여 실지 음성의 원음에 대한 음질의 충실 도를 임의의 집단에 대하여 비교하여 음질의 충실 도를 확인하였다. 추후의 연구를 통하여 DSP에 의한 실시간 처리 시스템의 구현을 하고자 한다.

• The Korean Journal of Pain
• /
• 제35권2호
• /
• pp.173-182
• /
• 2022

Background: Neurokinin-1 (NK1) and calcitonin gene-related peptide (CGRP) play a vital role in pain pathogenesis, and these proteins' antagonists have attracted attention as promising pharmaceutical candidates. The authors investigated the anti-nociceptive effect of co-administration of the CGRP antagonist and an NK1 antagonist on pain models compared to conventional single regimens. Methods: C57Bl/6J mice underwent sciatic nerve ligation for the neuropathic pain model and were injected with 4% formalin into the hind paw for the inflammatory pain model. Each model was divided into four groups: vehicle, NK1 antagonist, CGRP antagonist, and combination treatment groups. The NK1 antagonist aprepitant (BIBN4096, 1 mg/kg) or the CGRP antagonist olcegepant (MK-0869, 10 mg/kg) was injected intraperitoneally. Mechanical allodynia, thermal hypersensitivity, and anxiety-related behaviors were assessed using the von Frey, hot plate, and elevated plus-maze tests. The flinching and licking responses were also evaluated after formalin injection. Results: Co-administration of aprepitant and olcegepant more significantly alleviated pain behaviors than administration of single agents or vehicle, increasing the mechanical threshold and improving the response latency. Anxiety-related behaviors were also markedly improved after dual treatment compared with either naive mice or the neuropathic pain model in the dual treatment group. Flinching frequency and licking response after formalin injection decreased significantly in the dual treatment group. Isobolographic analysis showed a meaningful additive effect between the two compounds. Conclusions: A combination pharmacological therapy comprised of multiple neuropeptide antagonists could be a more effective therapeutic strategy for alleviating neuropathic or inflammatory pain.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
• /
• pp.211.2-211.2
• /
• 2015

In order to investigate the effect of front channel in DAL (dual active layer) TFT (thin film transistor), we successfully fabricated DAL TFT composed of ITZO and IGZO as active layer using the solution process. In this structure, ITZO and IGZO active layer were used as front and back channel, respectively. The front channel was changed from 0.05 to 0.2 M at fixed 0.3 M IGZO of back channel. When the mol concentration of front channel was increased, the threshold voltage (VTH) was increased from 2.0 to -11.9 V and off current also was increased from 10-12 to 10-11. This phenomenon is due to increasing the carrier concentration by increasing the volume of the front channel. The saturation mobility of DAL TFT with 0.05, 0.1, and 0.2 M ITZO were 0.45, 4.3, and $0.65cm2/V{\cdot}s$. Even though 0.2 M ITZO has higher carrier concentration than 0.05 and 0.1 M ITZO, the 0.1 M ITZO/0.3 M IGZO DAL TFT has the highest saturation mobility. This is due to channel defect such as pores and pin-holes. These defect sites were created during deposition process by solvent evaporation. Due to these defect sites, the 0.1 M ITZO/0.3 M IGZO DAL TFT shows the higher saturation mobility than that of DAL TFT with front channel of 0.2 M ITZO.

• 대한기계학회논문집
• /
• 제10권3호
• /
• pp.316-325
• /
• 1986

본 연구에서는 이상배합조직강에 있어서 피로균열진전거동의 미시조직 의존 성을 밟히기 위하여 제이상 마르텐사이트가 모상 페라이트를 둘러싼 마르텐사이트페라 이트 복합조직강을 준비하고 미시조직이 각각 다른 4종류의 시험편에 대하여 피로시험 을 실시한후 이에 의해 얻어진 피로균열진전속도를 균열휨과 균열닫힘을 통하여 검토 하였다.

• Journal of Electrical Engineering and information Science
• /
• 제3권2호
• /
• pp.261-266
• /
• 1998

This paper describes the fabrication and characterization of dual-polysilicon gated surface channel 0.1$\mu\textrm{m}$ CMOSFETs using BF2 and arsenic as channel dopants. We have used and LDD structure and 40${\AA}$ gate oxide as an insulator. To suppress short channel effects down to 0.1$\mu\textrm{m}$ channel length, shallow source/drain extensions implemented by low energy implantation and SSR(Super Steep Retrograde) channel structure were used. The threshold voltages of fabricated CMOSFETs are 0.6V. The maximum transconductance of nMOSFET is 315${\mu}$S/$\mu\textrm{m}$, and that of pMOSFET is 156 ${\mu}$S/$\mu\textrm{m}$. The drain saturation current of 418 ${\mu}$A/$\mu\textrm{m}$, 187${\mu}$A/$\mu\textrm{m}$ are obtained. Subthreshold swing is 85mV/dec and 88mV/dec, respectively. DIBL(Drain Induced Barrier Lowering) is below 100mV. In the device with 2000${\AA}$ thick gate polysilicon, depletion in polysilicon near the gate oxide results in an increase of equivalent gate oxide thickness and degradation of device characteristics. The gate delay time is measured to be 336psec at operation voltage of 2V.

• 전자공학회논문지B
• /
• 제33B권1호
• /
• pp.128-132
• /
• 1996

[1]에서 extended threshold Boolean filter(ETBF)의 부분 군인 self-dual ETBF가 중앙값 부여파기 출력의 가중 평균으로 표현되어짐을 보였다. 이 논문에서는 이 결과를 일반적인 ETBF로 확장한다. 특히, 모든 ETBF를 최솟값(또는 최댓값) 부여파기 출력의 가중 평균으로 표현할 수 있음을 보였다. 이 표현은 자연스럽게 윈도우(window)의 크기가 K보다 작거나 같은 부여파기만을 사용하는 K차 ETBF(K-ETBF)라 불리는 ETBF의 부분 군(subclass)을 제시한다. 여러 가지 K 값에 대하여 평균 제곱 오차(mean square error)를 최소화하는 K-ETBF를 설계한 후 이들을 오염된 신호의 복구에 적용함으로써 여파기의 성능과 복잡도간의 호환작용(tradeoff)을 고찰하였다.

• 한국콘텐츠학회논문지
• /
• 제13권10호
• /
• pp.46-53
• /
• 2013

원전 핵 연료봉에 대한 검사는 고준위 방사능의 위험으로부터 원격에서 이루어져야 하며, 또한 정확하게 이루어져야 한다. 현재 원전 핵 연료봉에 대한 검사는 방사능의 위험으로 인해 카메라로 핵 연료봉을 촬영하여 녹화된 동영상을 원격에서 보고 판단하는 형태로 운영되고 있다. 본 연구는 원자력 발전소에서 사용되는 핵 연료봉에 대한 상태 검사를 영상처리를 통하여 구현한 것이다. 핵 연료봉은 여러 개를 다발로 묶어 사용하도록 되어있는데, 이를 검사하기위한 영상처리 기법으로는 에지 검출 기법이 유용하다. 핵 연료봉 에지 검출을 위해 DoG 기법에 임계값 처리를 추가하는 방법을 제안한다. 이것은 DoG를 최적화한 새로운 기법으로, DoG와 임계값을 듀얼로 처리하는 방법이다. 이 방법으로 핵 연료봉 에지를 검출한 후에, 핵 연료봉 검사 알고리즘을 수행하여 핵 연료봉 이상 유무를 판단한다. 이러한 방법을 통해 미니어처로 제작된 핵 연료봉 검사시스템에 실험한 결과 우수한 특성을 확인하였다. 본 연구를 통해 원전 핵 연료봉 상태 검사를 보다 쉽고 안전하게 시행할 수 있을 것으로 생각된다.

• Journal of Positioning, Navigation, and Timing
• /
• 제8권3호
• /
• pp.95-105
• /
• 2019

A method that applies space-time adaptive signal processing (STAP) algorithm based on an array antenna consisting of multiple antenna elements has been known to be effective to remove wide-band jamming signals in GPS receivers. However, the occurrence of phase distortion in navigation signals has been a problem when navigation signals, from which jamming signals are removed using STAP, are supplied to global positioning system (GPS) receivers. This paper verified the navigation performance degradation as a result of phase distortion. To mitigate this phenomenon, this paper proposes a mode switching scheme, in which a bypass mode is adopted to make the best use of the tracking performance of receivers without performing signal processing when jamming signals are not present or weak, and a STAP mode is employed when jamming signals exceed the threshold value. In this paper, the mode switching scheme is proposed for two environments: when receivers are stationary, and when receivers are moving. This paper confirmed that the performance of position error improved because phase distortion could be excluded due to STAP if the bypass mode was adopted under a condition where the jamming signal power level was below the threshold value in an environment where receivers were stationary. However, this paper also observed that the navigation failed due to the instability of tracking performance of receivers due to phase distortion that occurred at the switching time, although the number of switching could be reduced dramatically by proposing a dual threshold scheme of on- and off-thresholds that switched a mode due to the array antenna characteristics of varying gains according to the jamming signal incident direction in an environment where receivers were moving. The analysis results verified that running the STAP algorithm at all times is more efficient than the mode switching, in terms of maintaining stable navigation and ensuring position error performance, to remove jamming signals in an environment where receivers were moving.

• 대한전자공학회논문지SD
• /
• 제46권12호
• /
• pp.80-86
• /
• 2009

전하펌프의 성능은 공급전압에 의해 크게 영향을 받는다. 본 논문에서는 표준 twin-well CMOS 로직 공정으로 제작 가능하며, 낮은 공급전압에서도 높은 효율을 갖는 새로운 전하펌프 회로를 제안하고 검증하였다. 제안한 전하펌프는 이중의 전하 전달 경로와 간단한 2-phase 클락을 사용한다. 한 주기의 펌핑 사이클 동안 각 펌핑 단에서 입력전압을 2배로 승압하며, 상보적으로 연결된 PMOS 트랜지스터를 전달 스위치로 사용하여 트랜지스터의 문턱전압에 의한 전압강하 없이 승압된 전압을 다음 승압 단으로 전달한다. 시뮬레이션과 측정을 통해 제안한 전하펌프를 검증하였으며, 동일한 공정조건에서 제작 가능한 기존 전하펌프들 보다 높은 출력전압과 큰 전류 구동능력 그리고 더 높은 전력효율을 가진다는 것을 확인하였다.

• 한국가족관계학회지
• /
• 제22권3호
• /
• pp.47-72
• /
• 2017

Objectives: Do husbands with working wives share domestic labor more equally than husbands with unemployed housewives? Is the husband's contribution sufficient enough to satisfy his wife? These questions have long inspired many researchers to find ways to more accurately estimate husband's domestic contributions and narrow the emotional gap following the different threshold of satisfaction within couples, but not without some limits. This study attempted to figure out an answer to the above-mentioned subject by using time diaries of Korean married couples with a preschooler as their first-born child and relying on the typology of husbands' sharing of housework and childcare, which allowed me to overcome some limitations of prior research. Method: I analyzed a total of 1,716 diaries of 858 married couples from 2014 Korea Time Use Survey with descriptive statistics, t-test, cluster analysis, and multinomial logit. Results: Analytic results showed that husbands in dual-earner households did share domestic labor more equally than husbands in single-earner households, but there were different types of husband's contribution depending on time they spent in housework and childcare. While more than half of husbands with employed wives shared more or less than ten percent of domestic labor, the rest were divided into one group of husbands who shared both housework and childcare more heavily and evenly, and another group who were mainly involved in childcare duties. It is interesting that husbands who made the least contributions to domestic labor were not the ones with the lowest level of satisfaction with their sharing of household labor, whereas their wives were deeply dissatisfied, leading to a huge emotional gap within couples. Conclusion: Identifying factors associated with the three different types allowed me to find a point of intervention to narrow the emotional gap that is likely to harm the marital relationship if left unattended to.