• 한국통신학회논문지
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• 제37권7A호
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• pp.503-511
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• 2012

이 논문은 지연프레임 시간다이버시티(DFTD)를 외부코드로 사용하고 RS 코드를 내부코드로 사용하는 원격측정방식의 성능분석에 대하여 기술한다. DFTD는 탑재장치에서 실시간 프레임과 더불어 임의 시간동안 지연된 프레임을 함께 전송하고 지상에서 각 프레임을 병합하는 방식이다. RS 코드는 DFTD에 직렬로 연결되어지는 FEC(forward error correction) 코드이다. 이 방식을 원격측정장치 설계에 적용하여 깊은 페이딩이 존재하는 통신환경에서 비행시험을 수행하였다. 비행시험 결과를 사용하여 코드적용이 없을 경우, DFTD만 적용할 경우, RS 코드만 적용할 경우와 DFTD와 RS 코드를 함께 적용할 경우에 대하여 각각의 성능을 분석한다. 시간지연 모의는 모든 프레임오류 제거 가능성을 보여주고 12회 비행시험 결과는 새로운 원격측정방식의 성능 우수성을 RS코드만 적용하였을 경우와 비교하여 보여준다.

• Archives of Plastic Surgery
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• 제41권3호
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• pp.264-270
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• 2014

Background The technique of delayed-immediate breast reconstruction includes immediate insertion of a tissue expander, post-mastectomy radiation, followed by reconstruction. The aesthetic benefits of delayed-immediate reconstruction compared to delayed reconstruction are postulated but remain unproven. The purpose of this study was to compare aesthetic outcomes in patients following delayed and delayed-immediate autologous breast reconstruction. Methods A retrospective analysis was performed of all patients who underwent delayed or delayed-immediate autologous breast reconstruction by the senior author from 2005 to 2011. Postoperative photographs were used to evaluate aesthetic outcomes: skin quality, scar formation, superior pole contour, inferior pole contour, and overall aesthetic outcome. Ten non-biased reviewers assessed outcomes using a 5-point Likert scale. Fisher's Exact and Wilcoxon-Mann-Whitney tests were used for comparative analysis. Results Patient age and body mass index were similar between delayed (n=20) and delayed-immediate (n=20) cohorts (P>0.05). Skin and scar quality was rated significantly higher in the delayed-immediate cohort (3.74 vs. 3.05, P<0.001 and 3.41 vs. 2.79, P<0.001; respectively). Assessment of contour-related parameters, superior pole and inferior pole, found significantly improved outcomes in the delayed-immediate cohort (3.67 vs. 2.96, P<0.001 and 3.84 vs. 3.06, P<0.001; respectively). Delayed-immediate breast reconstruction had a significantly higher overall score compared to delayed breast reconstructions (3.84 vs. 2.94, P<0.001). Smoking and the time interval from radiation to reconstruction were found to affect aesthetic outcomes (P<0.05). Conclusions Preservation of native mastectomy skin may allow for improved skin/scar quality, breast contour, and overall aesthetic outcomes following a delayed-immediate reconstructive algorithm as compared to delayed breast reconstruction.

• Journal of Periodontal and Implant Science
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• 제52권2호
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• pp.127-140
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• 2022

Purpose: In dental avulsion, delayed replantation usually has an uncertain prognosis. After tooth replantation, complex inflammatory responses promote a return to periodontal tissue homeostasis. Various types of cytokines are produced in the inflammatory microenvironment, and these cytokines determine the periodontal tissue response. This study aimed to identify the gene expression profiles of replanted teeth and evaluate the functional differences between immediate and delayed replantation. Methods: Maxillary molars from Sprague-Dawley rats were extracted, exposed to a dry environment, and then replanted. The animals were divided into 2 groups according to the extra-oral time: immediate replantation (dry for 5 minutes) and delayed replantation (dry for 60 minutes). Either 3 or 7 days after replantation, the animals were sacrificed. Periodontal soft tissues were harvested for mRNA sequencing. Hallmark gene set enrichment analysis was performed to predict the function of gene-gene interactions. The normalized enrichment score (NES) was calculated to determine functional differences. Results: The hallmark gene sets enriched in delayed replantation at 3 days were oxidative phosphorylation (NES=2.82, Q<0.001) and tumor necrosis factor-alpha (TNF-α) signaling via the nuclear factor kappa light chain enhancer of activated B cells (NF-κB) pathway (NES=1.52, Q=0.034). At 7 days after delayed replantation, TNF-α signaling via the NF-κB pathway (NES=-1.82, Q=0.002), angiogenesis (NES=-1.66, Q=0.01), and the transforming growth factor-beta signaling pathway (NES=-1.46, Q=0.051) were negatively highlighted. Conclusions: Differentially expressed gene profiles were significantly different between immediate and delayed replantation. TNF-α signaling via the NF-κB pathway was marked during the healing process. However, the enrichment score of this pathway changed in a time-dependent manner between immediate and delayed replantation.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 춘계종합학술대회
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• pp.629-632
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• 2003

This paper presents a way to maximize transmission efficiency and reception ability through transmission diversity technology, which can be adapted to wireless multimedia OFDM system. The presented method is a comparative analysis between a case where parameter $\alpha$for time average is 0.3, 1 with consideration of channel presumption with two types of rms delayed proliferation, which is 50nsec, 150nsec, for the performance analysis of STTC(Space-Time Trellis Code) using time-space ciphering method appropriate for MIMO channel, and performance in the case where presumed channel value from long training column section is applied to according frame in a single frame. The result showed that BER brought SNR improvement of 1.0dB in 10-3 when $\alpha$ was 0.3 than using only the long training column, and showed increase of general performance improvement for the sake of time average rather than the case without.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 I
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• pp.473-476
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• 2003

In this paper, presents a way to maximize transmission efficiency and reception ability through transmission diversity technology, which can be adapted to wireless multimedia OFDM system. The presented method is a comparative analysis between a case where parameter a for time average is 0.3, 1 with consideration of channel presumption with two types of rms delayed proliferation, which is 50nsec, 150nsec, for the performance analysis of STTC(Space-Time Trellis Code) using time-space code method appropriate for MIMO channel, and performance in the case where presumed channel value from long training column section is applied to according frame in a single frame. The result showed that BER brought SNR improvement of 1.0dB in 10$^{-3}$ when a was 0.3 than using only the long training column, and showed increase of general performance improvement for the sake of time average rather than the case without.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.845-849
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• 1992

The disturbance and time delay can often cause a significant error in the estimation of trajectory of a underwater vehicle. The time delay considered in this study is due to the delayed rudder response to the rudder input from the guidance control part. The simulation tests are performed on maneuver with constant rudder angle, zigzag maneuver, dive-climb maneuver, and corridor pattern maneuver. The results are compared with those of without delay cases.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.120-124
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• 1987

Linear time invariant systems are considered. It is assumed that only partial state variables are observable for feedback control. In this study, a new method is presented for designing a stat e feedback controller. It is based on augmenting the original system by additional integrator and using time delayed feedback of observable variables. Several examples and its computer simulation results are given to show the effectiveness of the proposed method.

• 한국지능시스템학회논문지
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• 제10권5호
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• pp.423-431
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• 2000

In this paper, the effect of computing time-delay in the real-time digital fuzzy control systems is investigated and the design methodology of a real-time digital fuzzy controller(DFC) to overcome the problems caused by it is presented. We propose the fuzzy feedback controller whose output is delayed with unit sampling period. The analysis and the design problem considering computing time-delay is very easy because the proposed controller is syncronized with the sampling time. The stabilization problem of the digital fuzzy control system is solved by the linear matrix inequality(LMI) theory. Convex optimization techniques are utilized to find the stable feedback gains and a common positive definite matrix P for the designed fuzzy control system Furthermore, we develop a real-time fuzzy control system for backing up a computer-simulated truck-trailer with the consideration of the computing time-delay. By using the proposed method, we design a DFC which guarantees the stability of the real time digital fuzzy control system in the presence of computing time-delay.

• 한국전문물리치료학회지
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• 제7권1호
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• pp.22-31
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• 2000

Despite research to treat delayed onset muscle soreness (DOMS), no effective treatment has been reported. The purpose of this study is to investigate the effect of a hold-relax technique and cryotherapy on DOMS. Thirty-three subjects were randomly assigned to one of three treatment groups: control, hold-relax technique, or hold-relax technique and cryotherapy. DOMS was induced in the non-dominant biceps muscle through repeated eccentric contractions. Resting elbow joint position, flexion and extension (universal goniometer), pain (Visual Analogue Scale; VAS), and WBC count (blood analysis) were measured one hour before DOMS was induced and 24, 48, and 72 hours after DOMS was induced. The data were analyzed by repeated measure of two-way ANOVA. The results of this study were summarized as follows: 1) While analysis showed no significant differences between groups in relation to a resting elbow joint position, there were significant differences over time, especially at 24, 48 hours after DOMS was induced compared with resting elbow joint position before DOMS was induced. 2) While analysis showed no significant differences between groups in relation to range of flexion, there were significant differences between range of flexion before DOMS was induced and range of flexion 72 hours after DOMS was induced. 3) There were no significant differences between groups or over time in relation to range of extension. 4) While analysis showed no significant differences between groups in relation to VAS, there were significant differences over time in different hours. 5) There were no significant differences between groups or over time in relation to WBC count. 6) There were no interactions between groups or over time in all variables. This results suggested that hold-relax technique and cryotherapy were not effective to reduce DOMS.

• Journal of Mechanical Science and Technology
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• 제20권7호
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• pp.950-960
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• 2006

An output time delay always exists in practical systems. Analysis of the delay phenomenon in a continuous-time domain is sophisticated. It is appropriate to obtain its corresponding discrete-time model for implementation via a digital computer. A new method for the discretization of nonlinear systems using Taylor series expansion and the zero-order hold assumption is proposed in this paper. This method is applied to the sampled-data representation of a nonlinear system with a constant output time-delay. In particular, the effect of the time-discretization method on key properties of nonlinear control systems, such as equilibrium properties and asymptotic stability, is examined. In addition, 'hybrid' discretization schemes resulting from a combination of the 'scaling and squaring' technique with the Taylor method are also proposed, especially under conditions of very low sampling rates. A performance of the proposed method is evaluated using two nonlinear systems with time-delay output.