• Title/Summary/Keyword: reduction procedures

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Speckle Noise Reduction and Edge Enhancement in Ultrasound Images Based on Wavelet Transform

  • Kim, Yong-Sun;Ra, Jong-Beom
    • Journal of Biomedical Engineering Research
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    • v.29 no.2
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    • pp.122-131
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    • 2008
  • For B-mode ultrasound images, we propose an image enhancement algorithm based on a multi-resolution approach, which consists of edge enhancing and noise reducing procedures. Edge enhancement processing is applied sequentially to coarse-to-fine resolution images obtained from wavelet-transformed data. In each resolution, the structural features of each pixel are examined through eigen analysis. Then, if a pixel belongs to an edge region, we perform two-step filtering: that is, directional smoothing is conducted along the tangential direction of the edge to improve continuity and directional sharpening is conducted along the normal direction to enhance the contrast. In addition, speckle noise is alleviated by proper attenuation of the wavelet coefficients of the homogeneous regions at each band. This region-based speckle-reduction scheme is differentiated from other methods that are based on the magnitude statistics of the wavelet coefficients. The proposed algorithm enhances edges regardless of changes in the resolution of an image, and the algorithm efficiently reduces speckle noise without affecting the sharpness of the edge. Hence, compared with existing algorithms, the proposed algorithm considerably improves the subjective image quality without providing any noticeable artifacts.

ALGORITHM OF REVISED-OTFTOOL

  • Chung Eun-Jung;Kim Hyor-Young;Rhee Myung-Hyun
    • Journal of Astronomy and Space Sciences
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    • v.23 no.3
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    • pp.269-288
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    • 2006
  • We revised the OTFTOOL which was developed in Five College Radio Astronomy Observatory (FCRAO) for the On-The-Fly (OTF) observation. Besides the improvement of data resampling function of conventional OTFTOOL, we added a new SELF referencing mode and data pre-reduction function. Since OTF observation data have a large redundancy, we can choose and use only good quality samples excluding bad samples. Sorting out the bad samples is based on the floating level, rms level, antenna trajectory, elevation, $T_{sys}$, and number of samples. And, spikes are also removed. Referencing method can be chosen between CLASSICAL mode in which the references are taken from the OFFs observation and ELLIPSOIDAL mode in which the references are taken from the inner source free region (this is named as SELF reference). Baseline is subtracted with the source free channel windows and the baseline order chosen by the user. Passing through these procedures, the raw OTF data will be an FITS datacube. The revised-OTFTOOL maximizes the advantages of OTF observation by sorting out the bad samples in the earliest stage. And the new self-referencing method, the ELLIPSOIDAL mode, is very powerful to reduce the data. Moreover since it is possible to see the datacube at once without moving them into other data reduction programs, it is very useful and convenient to check whether the data resampling works well or not. We expect that the revised-OTFTOOL can be applied to the facilities of the OTF observation like SRAO, NRAO, and FCRAO.

Reduction of Zygomatic Fractures Using the Carroll-Girard T-bar Screw

  • Baek, Ji Eun;Chung, Chan Min;Hong, In Pyo
    • Archives of Plastic Surgery
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    • v.39 no.5
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    • pp.556-560
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    • 2012
  • Zygomatic fractures are the second most common facial bone fractures encountered and treated by plastic surgeons. Stable fixation of fractured fragments after adequate exposure is critical for ensuring three-dimensional anatomic reduction. Between January 2008 and December 2010, 17 patients with zygomatic fractures were admitted to our hospital; there were 15 male and 2 female patients. The average age of the patients was 41 years (range, 19 to 75 years). We exposed the inferior orbital rim and zygomatic complex through a lateral brow, intraoral, and subciliary incisions, which allowed for visualization of the bone, and then the fractured parts were corrected using the Carroll-Girard T-bar screw. Postoperative complications such as malar asymmetry, diplopia, enophthalmos, and postoperative infection were not observed. Lower eyelid retraction and temporary ectropion occurred in 1 of the 17 patients. Functional and cosmetic results were excellent in nearly all of the cases. In this report, we describe using the Carroll-Girard T-bar screw for the reduction of zygomatic fractures. Because this instrument is easy to use and can rotate to any direction and vector, it can be used to correct displaced zygomatic bone more accurately and safely than other devices, without leaving facial scars.

Contralateral Breast Symmetrisation in Immediate Prosthetic Breast Reconstruction after Unilateral Nipple-Sparing Mastectomy: The Tailored Reduction/Augmentation Mammaplasty

  • Salgarello, Marzia;Visconti, Giuseppe;Barone-Adesi, Liliana;Franceschini, Gianluca;Masetti, Riccardo
    • Archives of Plastic Surgery
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    • v.42 no.3
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    • pp.302-308
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    • 2015
  • Background In the literature on nipple-sparing mastectomy (NSM) with one-stage immediate implant reconstruction, contralateral symmetrisation has drawn little attention, with many surgeons still performing standard cosmetic mammaplasty procedures. However, standard implant-based mammaplasty usually does not result in proper symmetry with the mastectomy side, especially regarding breast projection, overall shape, and volume distribution. Methods We retrospectively reviewed 19 consecutive patients undergoing unilateral NSM with immediate prosthetic reconstruction and contralateral simultaneous symmetrisation by using the tailored reduction/augmentation mammaplasty technique between June 2012 and August 2013. Results The average follow-up time was 13 months (range, 10-24 months). No major complications, such as infection, haematoma, and nipple-areola complex necrosis, were experienced. Conclusions Our experience suggests that simultaneous contralateral symmetrisation with tailored reduction/augmentation mammaplasty after unilateral immediate implant reconstruction after NSM facilitates durable and pleasant symmetric outcomes.

Identifying Dynamic Characteristics of the Traction Motor Housing For the Noise reduction of the Electric vehicle (전기자동차 소음저감을 위한 구동모터 하우징의 동특성 평가)

  • Park, Jongchan;Park, Seungyong;Cho, Hyun-Kyu;Park, Yunsu
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2012.10a
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    • pp.818-823
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    • 2012
  • Assessment of the dynamics properties, like damping, dynamic stiffness and resonance sharpness is essential for the development of a robust system, specifically for the reduction of a traction motor noise. A practical method for identifying dynamic characteristics of a traction motor hosing for an electric vehicle is proposed. Assembling using interference fit of the components of the motor is attributed to the main cause of strong nonlinearity. It is well known that nonlinearity of a structure makes it difficult to assess damping properties or dynamic characteristics of the system. This research presents a practical damping or dynamic stiffness identifying procedures for a nonlinear system according to the boundary condition between assembled components. Based on the simple idea that impact forces of modal tests are highly affected on the condition of the hammer tip, Auto Power Spectrum of the impact forces are used to assess the assembling condition and dynamic characteristics of the system, especially, damping of the system.

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Application and Effectiveness Analysis of SWAT Filter Strip in Golji Watershed (골지천 유역의 최적관리기법 적용에 따른 수질개선효과 분석)

  • Park, Youn Shik;Kwon, Jae Hyouk
    • Korean Journal of Environmental Agriculture
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    • v.33 no.1
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    • pp.30-36
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    • 2014
  • BACKGROUND: Best management practices are often implemented to control nonpoint source pollutants. Best management practices need to be simulated and analyzed for effective Best management practices implementations. Filter strip is one of effective Best management practices in agricultural areas. METHODS AND RESULTS: Soil and Water Assessment Tool model was selected to explore the effectiveness of filter strip to control total phosphorous in Golji watershed. Soil and Water Assessment Tool model was calibrated for flow and total phosphorous by Sequential Uncertainty Fittin ver.2 algorithm provided in Soil and Water Assessment Tool-Calibration and Uncertainty Procedures. Three scenarios defined by filter strip width were applied. The filter strip width of 5 m was able to reduce the most amount of total phosphorous. In other words, the total phosphorous reduction by filter strip of 5 m was 28.0%, while the reduction was 17.5% by filter strip of 1 m. However, the reduction per unit filter strip width were 17.4%, 8.0%, and 4.5% for 1 m, 3 m, and 5 m of filter strips, respectively. CONCLUSION: Best management practices need to be simulated and analyzed so that the BMP scenario can be cost-effective. A large size of BMP might be able to control large amount of pollutants, however it would not be indicated as a cost-effective strategy.

The effect of supportive periodontal therapy after periodontal treatment : A 1-year follow up. (치주치료 후 유지치주치료의 효과에 관한 평가 : 1년 관찰)

  • Kim, Shin-Young;Kim, Yong-Gun
    • The Journal of the Korean dental association
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    • v.55 no.1
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    • pp.22-29
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    • 2017
  • Purpose : Preservation of the periodontal health of the treated patient requires supportive periodontal therapy for the elimination of periodontal disease. After Phase I therapy is completed, patients are placed on a schedule of periodic recall visits for maintenance care to prevent recurrence of the disease. The amount of tooth loss would be the most relevant criterion in an evaluation of the effect of periodontal treatment, but this would require studies with extremely long follow-up periods. Thus the most commonly used outcome criteria in clinical research have been clinical attachment level change, reduction of pocket depth and bleeding frequency. The purpose of this case study is to identify the effect of supportive periodontal therapy after periodontal flap surgery. Materials & Methods : Following routine hygienic phase of treatment, patients with chronic periodontitis received surgical periodontal treatment. Bleeding on probing, pocket depth and clinical attachment level were measured at baseline, pre-operation and 1 year follow up. All procedures were performed by one operator. Results : One year a total of 28 patients (58sites) to recheck remained, when conducted maintenance program after periodontal flap surgery was observed reduction of bleeding frequency, pocket depth and improvement of clinical attachment level. Conclusion : The results from this study indicate that supportive periodontal therapy after periodontal flap surgery is effective for reduction of bleeding frequency, pocket depth and gain of clinical attachment level.

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An Adaptive Filtering Technique for Vibration Reduction of a Rotational LOS Control System and Frequency Noise Reduction of an Imaging System (적응형 필터링 기법을 이용한 회전형 시선제어시스템의 진동 저감 및 영상 주파수노이즈 저감 기법)

  • Kim, Byeong-Hak;Kim, Min-Young
    • Journal of Institute of Control, Robotics and Systems
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    • v.20 no.10
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    • pp.1014-1022
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    • 2014
  • In mechatronic systems using electric signals to drive control systems, driving signals including the frequency band of the unwanted signals, such as resonant frequencies and noise frequencies, can affect the accuracy of the controlled system and can cause serious damage to the system due to the resonance phenomenon of the mechatronic system. An LOS (Line of Sight) control unit is used to automatically rotate the gimbal system with a video imaging system generally mounted on modern aerial vehicles. However, it still suffers from natural frequency variation problems due to variations of operational temperature. To prevent degradation in performance, this paper proposes an adaptive filtering technique based on real-time noise analysis and adaptive notch-filtering for LOS control systems, and verifies how our proposed method maintains the LOS stabilization performance. Additionally, this filtering technique can be applied to the image noise filtering of the video imaging system. It is designed to reduce image noises generated by switching circuits or power sources. The details of design procedures of the proposed filtering technique and the experiments for the performance verification are described in this paper.

Minimally Invasive Plate Osteosynthesis of Radius-Ulna Fracture using Circular External Fixator in a Dog

  • Kwon, Yong-hwan;Kang, Jin-su;Kim, Young-ung;Cho, Hyoung-sun;Lee, Ki-chang;Kim, Nam-soo;Kim, Min-su
    • Journal of Veterinary Clinics
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    • v.34 no.1
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    • pp.47-49
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    • 2017
  • Fracture stabilization techniques continue to evolve and provide approaches that minimize the iatrogenic trauma associated with surgical procedures. Minimally invasive plate osteosynthesis (MIPO) is a recently described method of biological internal fixation performed by introducing a bone plate via small insertional incisions that are remote to the fracture site. Indirect reduction techniques can generally be utilized when performing MIPO. In this case report, we describe MIPO of a radius-ulna fracture by indirect reduction using circular external fixation for alignment and distraction in a dog.

Single-flap versus double-flap approach for periodontal pocket reduction in supraosseous defects: a comparative study

  • Mathala, Venkata Lakshmi;Konathala, Santosh Venkata Ramesh;Gottumukkala, Naga Venkata Satya Sruthima;Pasupuleti, Mohan Kumar;Bypalli, Vivek;Korukonda, Radharani
    • Journal of Periodontal and Implant Science
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    • v.51 no.4
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    • pp.239-253
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    • 2021
  • Purpose: The single-flap approach (SFA) is a minimally invasive technique with limited mucoperiosteal flap elevation to gain access to the buccal/palatal aspects, thus limiting post-surgical complications. The purpose of the present study was to gain insights into the impact of the SFA over the double-flap approach (DFA) on periodontal flap treatment outcomes and patient compliance in terms of discomfort and time taken for surgical procedures. Methods: Twenty patients with persistent probing pocket depths of ≥5 mm were scheduled for the SFA (test site) and for the DFA (control site). All the clinical periodontal parameters were recorded at baseline, 3 months, and 6 months. Radiographic bone level (cone-beam computed tomography) was evaluated at baseline and 6 months. Patients' postoperative pain perception and wound healing were also assessed. Results: The SFA showed a significant reduction in periodontal pocket depth, gain in clinical attachment level (CAL), and gain in bone level when compared with the DFA. The SFA substantially improved wound healing and induced less postoperative pain than the DFA. Conclusions: The SFA resulted in substantial improvement in the composite outcome measures, as shown by a reduction in pocket depth with minimal gingival recession, gain in CAL, early wound healing, less postoperative discomfort, and better patient-centered outcomes.