• Title/Summary/Keyword: Mean Reduction Method

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Internal Fixation of Proximal Humerus Fracture with Locking Compression Plate (잠김 압박 금속판을 이용한 근위 상완골 골절의 내고정술)

  • Park, Chul-Hyun;Park, Sung-Hyuk;Seo, Jae-Sung
    • Clinics in Shoulder and Elbow
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    • v.12 no.1
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    • pp.44-52
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    • 2009
  • Purpose: We assessed the radiographic and clinical results of one surgeon's experience treating proximal humerus fractures with a locked proximal humeral plate. Materials and Methods: Twenty patients with unstable proximal humerus fractures were treated with a locking compression plate between February 2005 and September 2007. The average age of the patients was 60.6 years, and the average postoperative follow-up period was 22.3 months. The clinical results were evaluated using the Constant and DASH scores. The radiologic results were evaluated by the Paavolainen method, which measures the neck shaft angle and humeral head height. Results: At the last follow-up examination, the mean Constant score was 75.3 and 15 cases (75%) had excellent or good results; the mean DASH score was 16.4. The mean neck shaft angle was $137.1^{\circ}$, and 19 cases (95%) had good results by the Paavolainen method. There was one delayed union, malunion, and screw loosening. Conclusion: The patients treated with a locking compression plate had relatively good clinical and radiologic results, and a low complication rate. Moreover, the patients could exercise earlier due to good reduction and initial stability. Treatment of unstable proximal humerus fractures with a locking compression plate is a reliable method.

Speckle Noise Removal by Rank-ordered Differences Diffusion Filter (순위 차 확산 필터를 이용한 스페클 잡음 제거)

  • Ye, Chul-Soo
    • Korean Journal of Remote Sensing
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    • v.25 no.1
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    • pp.21-30
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    • 2009
  • The purposes of this paper are to present a selection method of neighboring pixels whose local statistics are similar to the center pixel and combine the selection result with mean curvature diffusion filter to reduce noises in remote sensed imagery. The order of selection of neighboring pixels is critical, especially for finding a pixel belonging to the homogeneous region, since the statistics of the homogeneous region vary according to the selection order. An effective strategy for selecting neighboring pixels, which uses rank-order differences vector obtained by computing the intensity differences between the center pixel and neighboring pixels and arranging them in ascending order, is proposed in this paper. By using region growing method, we divide the elements of the rank-ordered differences vector into two groups, homogeneous rank-ordered differences vector and outlier rank-ordered differences vector. The mean curvature diffusion filter is combined with a line process, which chooses selectively diffusion coefficient of the neighboring pixels belonging into homogeneous rank-ordered differences vector. Experimental results using an aerial image and a TerraSAR-X satellite image showed that the proposed method reduced more efficiently noises than some conventional adaptive filters using all neighboring pixels in updating the center pixel.

Evaluation of the Usefulness of Restricted Respiratory Period at the Time of Radiotherapy for Non-Small Cell Lung Cancer Patient (비소세포성 폐암 환자의 방사선 치료 시 제한 호흡 주기의 유용성 평가)

  • Park, So-Yeon;Ahn, Jong-Ho;Suh, Jung-Min;Kim, Yung-Il;Kim, Jin-Man;Choi, Byung-Ki;Pyo, Hong-Ryul;Song, Ki-Won
    • The Journal of Korean Society for Radiation Therapy
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    • v.24 no.2
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    • pp.123-135
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    • 2012
  • Purpose: It is essential to minimize the movement of tumor due to respiratory movement at the time of respiration controlled radiotherapy of non-small cell lung cancer patient. Accordingly, this Study aims to evaluate the usefulness of restricted respiratory period by comparing and analyzing the treatment plans that apply free and restricted respiration period respectively. Materials and Methods: After having conducted training on 9 non-small cell lung cancer patients (tumor n=10) from April to December 2011 by using 'signal monitored-breathing (guided- breathing)' method for the 'free respiratory period' measured on the basis of the regular respiratory period of the patents and 'restricted respiratory period' that was intentionally reduced, total of 10 CT images for each of the respiration phases were acquired by carrying out 4D CT for treatment planning purpose by using RPM and 4-dimensional computed tomography simulator. Visual gross tumor volume (GTV) and internal target volume (ITV) that each of the observer 1 and observer 2 has set were measured and compared on the CT image of each respiratory interval. Moreover, the amplitude of movement of tumor was measured by measuring the center of mass (COM) at the phase of 0% which is the end-inspiration (EI) and at the phase of 50% which is the end-exhalation (EE). In addition, both observers established treatment plan that applied the 2 respiratory periods, and mean dose to normal lung (MDTNL) was compared and analyzed through dose-volume histogram (DVH). Moreover, normal tissue complication probability (NTCP) of the normal lung volume was compared by using dose-volume histogram analysis program (DVH analyzer v.1) and statistical analysis was performed in order to carry out quantitative evaluation of the measured data. Results: As the result of the analysis of the treatment plan that applied the 'restricted respiratory period' of the observer 1 and observer 2, there was reduction rate of 38.75% in the 3-dimensional direction movement of the tumor in comparison to the 'free respiratory period' in the case of the observer 1, while there reduction rate was 41.10% in the case of the observer 2. The results of measurement and comparison of the volumes, GTV and ITV, there was reduction rate of $14.96{\pm}9.44%$ for observer 1 and $19.86{\pm}10.62%$ for observer 2 in the case of GTV, while there was reduction rate of $8.91{\pm}5.91%$ for observer 1 and $15.52{\pm}9.01%$ for observer 2 in the case of ITV. The results of analysis and comparison of MDTNL and NTCP illustrated the reduction rate of MDTNL $3.98{\pm}5.62%$ for observer 1 and $7.62{\pm}10.29%$ for observer 2 in the case of MDTNL, while there was reduction rate of $21.70{\pm}28.27%$ for observer 1 and $37.83{\pm}49.93%$ for observer 2 in the case of NTCP. In addition, the results of analysis of correlation between the resultant values of the 2 observers, while there was significant difference between the observers for the 'free respiratory period', there was no significantly different reduction rates between the observers for 'restricted respiratory period. Conclusion: It was possible to verify the usefulness and appropriateness of 'restricted respiratory period' at the time of respiration controlled radiotherapy on non-small cell lung cancer patient as the treatment plan that applied 'restricted respiratory period' illustrated relative reduction in the evaluation factors in comparison to the 'free respiratory period.

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Energy Saving Characteristics on Burst Packet Configuration Method using Adaptive Inverse-function Buffering Interval in IP Core Networks (IP 네트워크에서 적응적 역함수 버퍼링 구간을 적용한 버스트패킷 구성 방식에서 에너지 절약 특성)

  • Han, Chimoon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.8
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    • pp.19-27
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    • 2016
  • Nowadays the adaptive buffering techniques for burst stream packet configuration and its operation algorithm to save energy in IP core network have been studied. This paper explains the selection method of packet buffering interval for energy saving when configuring burst stream packet at the ingress router in IP core network. Especially the adaptive buffering interval and its implementation scheme are required to improve the energy saving efficiency at the input part of the ingress router. In this paper, we propose the best adaptive buffering scheme that a current buffering interval is adaptively buffering scheme based on the input traffic of the past buffering interval, and analyze its characteristics of energy saving and end-to-end delay by computer simulation. We show the improvement of energy saving effect and reduction of mean delay variation when using an appropriate inverse-function selecting the buffering interval for the configuration of burst stream packet in this paper. We confirm this method have superior properties compared to other method. The proposed method shows that it is less sensitive to the various input traffic type of ingress router and a practical method.

Automatic Detection of Foreign Body through Template Matching in Industrial CT Volume Data (산업용 CT 볼륨데이터에서 템플릿 매칭을 통한 이물질 자동 검출)

  • Ji, Hye-Rim;Hong, Helen
    • Journal of Korea Multimedia Society
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    • v.16 no.12
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    • pp.1376-1384
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    • 2013
  • In this paper, we propose an automaticdetection method of foreign bodies through template matching in industrial CT volume data. Our method is composed of three main steps. First,Indown-sampling data, the product region is separated from background after noise reduction and initial foreign-body candidates are extracted using mean and standard deviation of the product region. Then foreign-body candidates are extracted using K-means clustering. Second, the foreign body with different intensity of product region is detected using template matching. At this time, the template matching is performed by evaluating SSD orjoint entropy according to the size of detected foreign-body candidates. Third, to improve thedetection rate of foreign body in original volume data, final foreign bodiesare detected using percolation method. For the performance evaluation of our method, industrial CT volume data and simulation data are used. Then visual inspection and accuracy assessment are performed and processing time is measured. For accuracy assessment, density-based detection method is used as comparative method and Dice's coefficient is measured.

Voice Personality Transformation Using a Probabilistic Method (확률적 방법을 이용한 음성 개성 변환)

  • Lee Ki-Seung
    • The Journal of the Acoustical Society of Korea
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    • v.24 no.3
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    • pp.150-159
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    • 2005
  • This paper addresses a voice personality transformation algorithm which makes one person's voices sound as if another person's voices. In the proposed method, one person's voices are represented by LPC cepstrum, pitch period and speaking rate, the appropriate transformation rules for each Parameter are constructed. The Gaussian Mixture Model (GMM) is used to model one speaker's LPC cepstrums and conditional probability is used to model the relationship between two speaker's LPC cepstrums. To obtain the parameters representing each probabilistic model. a Maximum Likelihood (ML) estimation method is employed. The transformed LPC cepstrums are obtained by using a Minimum Mean Square Error (MMSE) criterion. Pitch period and speaking rate are used as the parameters for prosody transformation, which is implemented by using the ratio of the average values. The proposed method reveals the superior performance to the previous VQ-based method in subjective measures including average cepstrum distance reduction ratio and likelihood increasing ratio. In subjective test. we obtained almost the same correct identification ratio as the previous method and we also confirmed that high qualify transformed speech is obtained, which is due to the smoothly evolving spectral contours over time.

A Study on the Problem-Solving Method and Thermal Efficiency Properties at the Time of High Expansion Realization in a 4-Cycle Diesel Engine (4사이클 디젤기관에서 고팽창 실현 시 문제점 해결방안과 열효율 특성에 대한 연구)

  • Jang, Tae-Ik
    • Journal of Advanced Marine Engineering and Technology
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    • v.33 no.6
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    • pp.835-842
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    • 2009
  • The present thesis carried out a research on a compression pressure's reduction phenomenon and its countermeasure according to the thermal efficiency improvement method by a Miller method in 4-cycle low speed diesel engine. In case of retardation of intake valve closing time in a engine, the theoretical heat efficiency shows a remarkably reducing trend when a compression ratio is not compensated. Accordingly, the thermal efficiency showed an increasing trend in case of compensating the compression ratio. Especially, it could be understood that the theoretical heat efficiency at near ABDC $100^{\circ}$ of intake valve closing time in case of compensation of the compression ratio was improved by around 25.1%, and the mean effective pressure was also increased by around 18.6%. Also, as the retardation of intake valve closing time increases, air quantity becomes insufficient due to a backflow phenomenon of intake air and thus thermal efficiency was decreased in a high load operation domain. The solving method of this problem is possible by supercharge. Therefore, in order to improve thermal efficiency by retardation of ntake valve closing time, the thermal efficiency improvement according to low compression is possible when there are a compensation device of a compression ratio and a supercharge device. This is a problem-solving method of low compression and high expansion cycle.

Wrap-around Motion Vector Prediction for 360 Video Streams in Versatile Video Coding (VVC에서 360 비디오를 위한 랩-어라운드 움직임 벡터 예측 방법)

  • Lee, Minhun;Lee, Jongseok;Park, Juntaek;Lim, Woong;Bang, Gun;Sim, Dong Gyu;Oh, Seoung-Jun
    • Journal of Broadcast Engineering
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    • v.25 no.3
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    • pp.313-324
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    • 2020
  • In this paper, we propose a motion vector prediction method that increases the coding efficiency at the boundary of an image by utilizing the 360 video characteristic. In the current VVC method, the location of a neighbor block is excluded from the candidate list for inter prediction in case that it is out of boundary. This can reduce coding efficiency as well as subject quality. To solve this problem, we construct new candidates adding the location of the neighbor block at the boundary of the picture from already decoded information based on the projection method for 360 video coding. To evaluate the performance of the proposed method, we compare with VTM6.0 and 360Lib9.1 under Random Access condition of JVET-360 CTC. As a result, the coding performance shows a BD-rate reduction of 0.02% on average in luma component and 0.05%, 0.06% on average in chroma components respectively, without additional computational complexity. The coding performance at the picture boundary shows a BD-rate reduction of 0.29% on average in luma component and 0.45%, 0.43% on average in chroma components, respectively. Furthermore, we perform subjective quality test with the DSCQS method and obtain MOS values. The MOS value is improved by 0.03 value, and we calculate BD-MOS using MOS value and bit-rate. As a result, the proposed method improved performance by up to 8.78% and 5.18% on average.

Transceiver Design Method for Finitely Large Numbers of Antenna Systems (유한 대용량 안테나 시스템에서 송수신기 설계 방법)

  • Shin, Joonwoo
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.3
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    • pp.280-285
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    • 2015
  • We consider a linear transceiver design method for multi-user multiple-input multiple-output (MIMO) downlink channels where a base station (BS) equipped with a finitely large number of antennas. Although a matched-filter precoder is a capacity-achieving method in massive MIMO downlink systems, it cannot guarantee to achieve the multi-user MIMO capacity in a finitely large number of antennas due to inter-user interferences. In this paper, we propose a two-stage precoder design method that maximizes the sum-rate of cell-edge users when the BS equipped with a finitely large number of antennas. At the first stage, a matched-filter precoder is adopted to exploit both beamforming gain and the reduction of the dimension of effective channels. Then, we derive the second stage precoder that maximizes the sum-rate by minimizing the weighted mean square error (WMSE). From simulation and analysis, we verify the effectiveness of the proposed method.

Real Time ECG Derived Respiratory Extraction from Heart Rate for Single Lead ECG Measurement using Conductive Textile Electrode (전도성 직물을 이용한 단일 리드 심전도 측정 및 실시간 심전도 유도 호흡 추출 방법에 관한 연구)

  • Yi, Kye-Hyoung;Park, Sung-Bin;Yoon, Hyoung-Ro
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.55 no.7
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    • pp.335-343
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    • 2006
  • We have designed the system that measure one channel ECG by two electrode and extract real-time EDR with more related resipiration and comportable to subject by using conductive textile. On the assumption that relation between RL electrode and potential measurement electrode is coupled with RC connected model, we designed RL drive output to feedback two electrode for reduction of common mode signal. The conductive textile which was used for two ECG electrode was offered more comfort during night sleep in bed than any other method using attachments. In the method of single-lead EDR, R wave point or QRS interval area could be used for EDR estimation in traditional method, it is, so to speak, the amplitude modulation(AM) method for EDR. Alternatively, R-R interval could be used for frequency modulation(FM) method based on Respiratory Sinus Arrhythmia(RSA). For evaluation of performance on AM EDR and FM EDR from 14 subject, ECG lead III was measured. Each EDR was compared with both temperature around nose(direct measurement of respiration) and respiration signal from thoracic belt(indirect measurement of respiration) on mean squared error(MSE), cross correlation(Xcorr), and Coherence. The upsampling interpolation technique of multirate signal processing is applied to interpolating data instead of cubic spline interpolation. As a result, we showed the real-time EDR extraction processing to be implemented at micro-controller.