• 제목/요약/키워드: Median point

검색결과 254건 처리시간 0.026초

장구간 예측 필터를 이용한 음성 신호에서의 돌발 잡음 제거 (Transient Noise Reduction in Speech Signal Utilizing a Long-term Predictor)

  • 최민석;강홍구
    • 한국음향학회지
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    • 제31권1호
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    • pp.29-38
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    • 2012
  • 본 논문에서는 음성 신호에 더해진 돌발 잡음을 제거하는 시스템을 제안한다. 제안한 돌발 잡음 제거 시스템은 중앙값 필터를 이용하여 돌발 잡음을 제거한다. 중앙값 필터는 잡음을 제거하는 과정에서 음성을 왜곡시킬 수 있기 때문에, 음성의 왜곡을 최소화하기 위하여 장구간 예측 필터를 전처리단으로 사용한다. 장구간 예측 필터로 보존된 음성 정보는 잡음이 제거된 후 다시 합성된다. 본 논문에서는 돌발 잡음이 존재하는 환경에서 음성의 정보를 보존하는데 있어 단구간 예측 필터의 문제점을 밝히고 장구간 예측 필터의 우수함을 보인다. 제안한 돌발 잡음 제거 시스템의 출력 신호는 입력 신호에 비해 음성이 존재하는 구간에서 신호 대 잡음비가 약 8dB 향상 되었으며, PESQ 점수가 약 1점 증가하였다.

Radiation for persistent or recurrent epithelial ovarian cancer: a need for reassessment

  • Choi, Noorie;Chang, Ji Hyun;Kim, Suzy;Kim, Hak Jae
    • Radiation Oncology Journal
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    • 제35권2호
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    • pp.144-152
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    • 2017
  • Purpose: The role of radiotherapy (RT) was largely deserted after the introduction of platinum-based chemotherapy, but still survival rates are disappointingly low. This study focuses on assessing the clinical efficacy of RT in relation to chemotherapy resistance. Materials and Methods: From October 2002 to January 2015, 44 patients were diagnosed with epithelial ovarian cancer (EOC) and treated with palliative RT for persistent or recurrent EOC. All patients received initial treatment with optimal debulking surgery and adjuvant platinum-based chemotherapy. The biologically effective dose (BED) was calculated with ${\alpha}/{\beta}$ set at 10. Ninety-four sites were treated with RT with a median BED of 50.7 Gy (range 28.0 to 79.2 Gy). The primary end-point was the in-field local control (LC) interval, defined as the time interval from the date RT was completed to the date any progressive or newly recurring disease within the RT field was detected on radiographic imaging. Results: The median follow-up duration was 52.3 months (range 7.7 to 179.0 months). The 1-year and 2-year in-field LC rates were 66.0% and 55.0%, respectively. Comparisons of percent change of in-field tumor response showed similar distribution of responses among chemoresistant and chemosensitive tumors. On multivariate analysis of predictive factors for in-field LC analyzed by sites treated, $BED{\geq}50Gy$ (hazard ratio, 0.4; confidence interval, 0.2-0.9; p = 0.025) showed better outcomes. Conclusion: Regardless of resistance to platinum-based chemotherapy, RT can be a feasible treatment modality for patients with persistent of recurrent EOC. The specific role of RT using updated approaches needs to be reassessed.

악관절장애 환자의 하악골 비대칭에 대한 방사선학적 연구 (A RADIOGRAPHIC STUDY OF THE MANDIBULAR ASYMMETRY IN TEMPOROMANDIBULAR DISORDER PATIENTS)

  • 오성국;유동수
    • 치과방사선
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    • 제20권2호
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    • pp.201-210
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    • 1990
  • The purpose of this study was to observe the relationship between mandibular asymmetry and Temporomandibular Disorders by means of the cephalometry using the posteroanterior cephalogram and the submentovertex cephalogram which were taken in 35 Temporomandibular Disorder patients and 35 normal persons ranged from 20S to 30S. The results were as follows: 1. The angulation which was formed by the median line with the ANS-Menton line (MAP) was greater in patients group and there was statistically significant difference. 2. The angulation which was formed to the median line with the Menton-Odontoid process tip line (MES), the difference of the distances from the center of the posterior surface of the both condyles to the most anterior point of the chin (DD), the difference of the distances from the center of the both condyles to the horizontal reference line (DE), the difference of the angulations which were formed by the both condyles axes with the horizontal reference line (DCE), the difference of the lengths of the both condyles (CL) and the difference of the widths of the both condyles (DW) were greater in patients group and there were statistically significant differences. There was reversed correlation between MAP and the difference of the distances from the 3. bilateral points of the lateral margin of the both zygomaticofrontal sutures to the at the lateral inferior margin of the both antegonial protuberances in mandible (DH). There was reversed correlation between MES and DD, DE, DCE. 5. There was correlation between MAP and MES.

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알루미나 세라믹스의 반복적 균열치유 특성 (Cyclic Crack Healing Effect of Al2O3 Ceramics)

  • 문창권;김부안
    • 한국해양공학회지
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    • 제27권2호
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    • pp.69-74
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    • 2013
  • In this study, the crack healing effects of $Al_2O_3$ ceramics based on the heat treatment conditions were investigated. The influence of the additive amounts of SiC nanoparticles and the cycling process of indentation-heat treatment on the crack healing effect of $Al_2O_3$ ceramics were also examined. Three-point bending tests were carried out and the morphological changes in the fracture surface were observed by using FE-SEM. As a result, heat-treated samples in a vacuum or air atmosphere showed improved bending strengths compared to un-heat treated samples. This means that cracked specimens can be healed by heat treatment in a vacuum or air atmosphere. The crack healing effect of $Al_2O_3$ ceramics that were heat treated in an air atmosphere was much higher than that of those heat treated in a vacuum. After heat treatment, the $Al_2O_3$ ceramics with 30 wt% SiC nanoparticles showed a higher bending strength than those with 15 wt% SiC. The cyclic indentation and heat treatment did not remarkably affect the crack healing effect. The SEM images showed that the median crack, indenter mark on the surface, and pores in the fracture surface of a specimen almost disappeared after being heat treated in an air atmosphere.

Sensory assessment of meshed skin grafts over free gracilis muscle flaps without nerve coaptation for lower extremity reconstruction

  • Tremp, Mathias;Waldkircher, Natascha J.;Wang, Wenjin;Oranges, Carlo M.;di Summa, Pietro G.;Zhang, Yixin;Wang, Wei;Schaefer, Dirk J.;Kalbermatten, Daniel F.
    • Archives of Plastic Surgery
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    • 제48권2호
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    • pp.224-230
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    • 2021
  • Background Little is known about the sensate recovery of skin grafts over free non-neurotized muscle flaps. The aim of this study was to evaluate the sensitivity of free gracilis muscle flaps and meshed skin grafts without nerve coaptation. Methods Thirteen consecutive patients with a median age of 55 years (range, 21-70 years) who underwent lower extremity reconstruction between September 2014 and October 2016 were included. Complications, flap contour, skin perception, and sensate recovery were assessed. Results All flaps survived completely. In one patient, wound dehiscence and infection occurred 1 month after surgery. After a median follow-up of 14 months (range, 10-51 months), a satisfactory contour and skin perception were achieved. The Semmes-Weinstein (SW) monofilament test (154.8±22 g) and static two-point discrimination (2-PD) (12.6±0.7 mm) showed intermediate recovery compared to the surrounding site (41% and 76%, respectively). There was an intermediate correlation between flap size and sensate recovery (2-PD: r=0.27, P=0.36; SW test: r=0.45, P=0.12). Vibration sensation recovered to 60%, whereas thermal sensation remained poor (19% at 5℃ and 25% at 25℃). Conclusions Finer sensation could be partially restored. However, thermal sensation remained poor.

Triggered Electrooculography for Identification of Oculomotor and Abducens Nerves during Skull Base Surgery

  • Jeong, Ha-Neul;Ahn, Sang-Il;Na, Minkyun;Yoo, Jihwan;Kim, Woohyun;Jung, In-Ho;Kang, Soobin;Kim, Seung Min;Shin, Ha Young;Chang, Jong Hee;Kim, Eui Hyun
    • Journal of Korean Neurosurgical Society
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    • 제64권2호
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    • pp.282-288
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    • 2021
  • Objective : Electrooculography (EOG) records eyeball movements as changes in the potential difference between the negatively charged retina and the positively charged cornea. We aimed to investigate whether reliable EOG waveforms can be evoked by electrical stimulation of the oculomotor and abducens nerves during skull base surgery. Methods : We retrospectively reviewed the records of 18 patients who had undergone a skull base tumor surgery using EOG (11 craniotomies and seven endonasal endoscopic surgeries). Stimulation was performed at 5 Hz with a stimulus duration of 200 μs and an intensity of 0.1-5 mA using a concentric bipolar probe. Recording electrodes were placed on the upper (active) and lower (reference) eyelids, and on the outer corners of both eyes; the active electrode was placed on the contralateral side. Results : Reproducibly triggered EOG waveforms were observed in all cases. Electrical stimulation of cranial nerves (CNs) III and VI elicited positive waveforms and negative waveforms, respectively, in the horizontal recording. The median latencies were 3.1 and 0.5 ms for craniotomies and endonasal endoscopic surgeries, respectively (p=0.007). Additionally, the median amplitudes were 33.7 and 46.4 μV for craniotomies and endonasal endoscopic surgeries, respectively (p=0.40). Conclusion : This study showed reliably triggered EOG waveforms with stimulation of CNs III and VI during skull base surgery. The latency was different according to the point of stimulation and thus predictable. As EOG is noninvasive and relatively easy to perform, it can be used to identify the ocular motor nerves during surgeries as an alternative of electromyography.

The incidence of unexpected delays in uploading outside radiologic images in the transfer of patients with major trauma

  • Woo, Si Jun;Kim, Yong Oh;Kim, Hyung Il
    • Journal of Trauma and Injury
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    • 제35권2호
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    • pp.92-98
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    • 2022
  • Purpose: Critically ill patients are frequently transferred from one point of care to a hospital that can provide a higher level of care. To achieve optimal treatment within the targeted window of time necessary for time-sensitive cases like major trauma, rapid transportation and decision making are essential. Transferred patients have often undergone radiologic imaging at the referring hospital. Examining these outside images is paramount. Therefore, this study was conducted to estimate the upload time of outside images. Methods: This retrospective study was conducted from January to April 2020. Patients transferred from other hospitals with digitally recorded CDs or DVDs of radiologic or diagnostic images were included. When the patients were registered at the emergency department reception desk, the digital images were transmitted to our picture archiving and communication system using transmission software. The time of upload and the numbers of digital images were recorded. The time interval from patient registration to the time of upload was calculated. Results: The median number of images was 688 in the trauma team activation (TTA) group (688 in the TTA group, 281 in the non-TTA trauma group, and 176 in the nontrauma group, respectively; P<0.001). The median upload time was 10 minutes. The longest upload time was 169 minutes. The upload time was more than 20 minutes in 12 cases (19.4%). Conclusions: Patients with major trauma bring more images than patients with other diseases. Unexpected delays (>20 minutes) were noted in approximately 20% of cases. It is necessary to minimize this time.

속도 향상을 위한 서포트 벡터 머신의 파라미터 탐색 방법론 (Parameter search methodology of support vector machines for improving performance)

  • 이성보;김재영;김철홍;김종면
    • 예술인문사회 융합 멀티미디어 논문지
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    • 제7권3호
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    • pp.329-337
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    • 2017
  • 본 논문에서는 서포트 벡터 머신의 중요한 파라미터인 C와 σ값을 빠르고 정확하게 찾는 탐색 방법론을 제안한다. 기존에 알려진 격자 탐색 방식은 모든 경우를 비교하기 때문에 탐색속도가 느리다. 이러한 문제점을 개선하기 위해 본 논문에서는 탐색속도 향상을 위한 딥 서치 방식을 제안한다. 1단계에서는 C-σ 정확도지표를 4등분 한 뒤 각 영역의 중간 값을 탐색하여 가장 정확도 값이 높은 지점을 시작 지점으로 선택한다. 2단계에서는 선정된 시작지점을 다시 4등분한 뒤 정확도 값이 가장 큰 지점을 새로운 탐색지점으로 지정한다. 3단계에서는 탐색지점에 이웃한 8개의 지점들을 탐색하여 정확도 값이 가장 높은 곳을 새로운 시작 지점으로 선정한 뒤 해당 지점을 4등분하여 정확도 값을 계산한다. 마지막 단계에서는 이웃 지점의 값들보다 탐색지점의 정확도지표 값이 최댓값이 될 때까지 진행한다. 최댓값을 만족하지 않을시 2단계에서부터 반복하며 입력된 레벨 값만큼 반복을 진행한다. 베어링의 결함 및 정상 데이터를 사용하여 비교한 결과, 제안한 Deep search 알고리즘은 기존 알고리즘 보다 성능 및 탐색시간에서 우수성을 보였다.

음포혈(陰包, LR9)에서 펄스형 전자기장 및 가시광 LED 복합 자극이 대퇴부 근피로 회복에 미치는 영향 분석 (The Analysis of the Muscle Fatigue Recovery Effect on LR9 by Compound Stimulation of the PEMFs and LED)

  • 이나라;김정윤;박선우;김수병;이희영;안순재;김영호;이용흠
    • Korean Journal of Acupuncture
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    • 제28권3호
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    • pp.13-23
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    • 2011
  • Objectives : The aim of this study was to develop the combined medical stimulus system consisted of the PEMFs (Pulsed electromagnetic fields) and LED which are able to stimulate local point such as acupoints and trigger points. Methods : To evaluate the therapeutic effect on the musculoskeletal disorders and the possibility of alternative method on manual acupuncture, we compared the fatigue recovery of two groups by analyzing the EMG and peak torque (non-stimulation and, stimulation group) after strenuous knee exercise. We chose the LR9 as a stimulation point. Results : The median frequency (MF) and fatigue index (F.I) of the stimulation group were recovered faster than those of the non-stimulation group. Also the peak torques of both groups were not restored until after 20 minutes. However, the peak torque of the stimulation group was regained higher than that of the non-stimulation group. Conclusions : We confirmed that the proposed combined stimulus system had useful effects as treatment instrument of musculoskeletal disorder using non-invasive method of PEMFs and LED.

일부 농촌지역 주민들의 수지 이점식별 및 관련요인 (Two-Point Discrimination of Fingertips and Related Factors in Rural Community Residents)

  • 이승주;신현욱
    • The Journal of Korean Physical Therapy
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    • 제18권5호
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    • pp.13-23
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    • 2006
  • Purpose: This study was to investigate two-point discrimination(TPD) and related factors in rural community residents. Methods: The sample consisted of 68 people who have been living in rural community in June 2005 studied. TPD was measured from the tips of the thumb, index, middle, ring, and little finger of each hand with the TPD esthesiometer. The research was designed to be a cross-sectional measured study. SAS statistical software was used for the analysis. The characteristics of the study sample were described by mean and standard deviation(SD) for continuous variables and by frequency and percentage for categorical variables. The Student's t-test and analysis of variance (ANOVA) were used to compare TPD in gender and diabetes mellitus. A Pearson's correlation analysis was conducted for relationship among values of 5 fingers. Multiple regression analysis was performed to determine the factors associated with TPD. Results: A total of 68 residents were measured, their average $age{\pm}SD$ was $54.2{\pm}23.2$ years(range: $12{\sim}88\;yr$). The mean TPD for 5 fingers tips in dominated side was 4.76mm(thumb 3.98mm, index 4.22mm, middle 4.79mm, ring 5.17mm, and little finger 5.65mm, respectively). 4.91mm for thumb finger of women was significantly higher than 3.54mm that of men's in difference between gender(p=.01l4), also women(4.39mm) was higher than men(3.71mm) in median nerver area(p=.0318). There was a statistically significant difference in age(p=.0022), which were under age of 20(3.36mm), 30 years(3.61mm), 40 years(5.38mm), 50 years(4.84mm), 60 years(5.28mm), 70 years(5.18mm), and over age of 80(5.29mm). Factors related to TPD of fiver fingers by multiple regressions were gender(${\beta}=.03$, p=.0001). Conclusions: Taken together, gender and age were significantly associated with TPD. We recommend that further research should measure TPD by using larger sample sizes and more sensitive measurement instruments.

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