• Title/Summary/Keyword: response reconstruction

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A New Focus Measure Method Based on Mathematical Morphology for 3D Shape Recovery (3차원 형상 복원을 위한 수학적 모폴로지 기반의 초점 측도 기법)

  • Mahmood, Muhammad Tariq;Choi, Young Kyu
    • KIPS Transactions on Software and Data Engineering
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    • v.6 no.1
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    • pp.23-28
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    • 2017
  • Shape from focus (SFF) is a technique used to reconstruct 3D shape of objects from a sequence of images obtained at different focus settings of the lens. In this paper, a new shape from focus method for 3D reconstruction of microscopic objects is described, which is based on gradient operator in Mathematical Morphology. Conventionally, in SFF methods, a single focus measure is used for measuring the focus quality. Due to the complex shape and texture of microscopic objects, single measure based operators are not sufficient, so we propose morphological operators with multi-structuring elements for computing the focus values. Finally, an optimal focus measure is obtained by combining the response of all focus measures. The experimental results showed that the proposed algorithm has provided more accurate depth maps than the existing methods in terms of three-dimensional shape recovery.

The Reconstructive Method for The Enhancement of Depth Resolution for Acoustic Image using the Spatial Frequency Response in NPPs' Material (NPP 매질내에서 공간주파수 응답을 이용한 초음파 영상의 깊이 분해능 개선을 위한 복원 방법)

  • Koo, Gil-mo;Kim, Hyun;Park, In-ho
    • Journal of Korea Multimedia Society
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    • v.5 no.4
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    • pp.426-433
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    • 2002
  • In this paper, we have studied the images which have been reconstructed by using combination of images acquired by the variation of operating frequency. When inner images have been reconstructed, they have been superposed by the surface state effect. In this case, the images of the phase object can be enhanced by the contrast of inner images. In this experiment, there are two kinds of specimens, one is a reference block haying 1/4T, 1/2T, 3/4T side drilled holes as main run piping material 111 the steam generator in NPP(Neuclear Power Plant)s and the another is a part of a hemisphere type specimen having about 1-2㎜ distance gap. It has been shown that the two results of defect shapes have better than before in this processing and phase contrast grow about twice. And we have constructed the acoustic microscope by using a quadrature detector that enables to acquire the amplitude and phase of the reflected signal simultaneously Further more ore have studied the reconstruction method of the amplitude and phase images and the enhancement method of the defect images contrast.

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Cryo-Compression Therapy After Elective Spinal Surgery for Pain Management: A Cross-Sectional Study With Historical Control

  • Nabiyev, Vugar Nabi;Ayhan, Selim;Adhikari, Prashant;Cetin, Engin;Palaoglu, Selcuk;Acaroglu, R. Emre
    • Neurospine
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    • v.15 no.4
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    • pp.348-352
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    • 2018
  • Objective: Postoperative dynamic cryo-compression (DC) therapy has been proposed as a method of reducing pain and the inflammatory response in the early postoperative period after orthopedic joint reconstruction surgery. Our aim was to analyze the analgesic efficacy of DC therapy after adult lumbar spinal surgery. Methods: DC was applied for 30 minutes every 6 hours after surgery. Pain was measured by a visual analogue scale (VAS) in the preoperative period, immediately after surgery, and every 6 hours postoperatively for the first 72 hours of the hospital stay. Patients' pain medication requirements were monitored using the patient-controlled analgesia system and patient charts. Twenty patients who received DC therapy were compared to 20 historical controls who were matched for demographic and surgical variables. Results: In the postanesthesia care unit, the mean VAS back pain score was $5.87{\pm}0.9$ in the DC group and $6.95{\pm}1.0$ (p=0.001) in the control group. The corresponding mean VAS scores for the DC vs. control groups were $3.8{\pm}1.1$ vs. $5.4{\pm}0.7$ (p < 0.001) at 6 hours postoperatively, and $2.7{\pm}0.7$ vs. $6.25{\pm}0.9$ (p<0.001) at discharge, respectively. The cumulative mean analgesic consumption of paracetamol, tenoxicam, and tramadol in the DC group vs. control group was $3,733.3{\pm}562.7mg$ vs. $4,633.3{\pm}693.5mg$ (p<0.005), $53.3{\pm}19.5mg$ vs. $85.3{\pm}33.4mg$ (p<0.005), and $63.3{\pm}83.4mg$ vs. $393.3{\pm}79.9mg$ (p<0.0001), respectively. Conclusion: The results of this study demonstrated a positive association between the use of DC therapy and accelerated improvement in patients during early rehabilitation after adult spine surgery compared to patients who were treated with painkillers only.

The complete mitochondrial genome of the blue-tailed damselfly Ischnura elegans (Odonata: Coenagrionidae)-a climate-sensitive indicator species in South Korea

  • Seung Hyun Lee;Jeong Sun Park;Jee-Young Pyo;Sung-Soo Kim;Iksoo Kim
    • International Journal of Industrial Entomology and Biomaterials
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    • v.46 no.2
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    • pp.41-54
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    • 2023
  • The blue-tailed damselfly, Ischnura elegans Van der Linden, 1820 (Odonata: Coenagrionidae), is a climate-sensitive indicator species in South Korea. In this study, we sequenced the complete mitochondrial genome (mitogenome) of I. elegans collected from South Korea for subsequent population genetic analysis, particularly to trace population movements in response to climate change. The 15,963 base pair (bp)-long complete mitogenome of I. elegans has typical sets of genes including a major non-coding region (the A+T-rich region), and an arrangement identical to that observed in ancestral insect species. The ATP6, ND3 and ND1 genes have the TTG start codon, which, although rare, is the canonical start codon for animal mitochondrial tRNA. The A/T content was 71.4% in protein-coding genes, 72.1% in tRNAs, 72.9% in the whole genome, 74.7% in srRNA, 75.3% in lrRNA, and 83.8% in the A+T-rich region. The A+T-rich region is unusually long (1,196 bp) and contains two subunits (192 bp and 176-165 bp), each of which is tandemly triplicated and surrounded by non-repeat sequences. Comparison of the sequence divergence among available mitogenomes of I. elegans, including the one from the current study, revealed ND2 as the most variable gene, followed by COII and COI, suggesting that ND2 should be targeted first in subsequent population-level studies. Phylogenetic reconstruction based on all available mitogenome sequences of Coenagrionidae showed a strong sister relationship between I. elegans and I. senegalensis.

Evaluation method and experimental study on seismic performance of column-supported group silo

  • Jia Chen;Yonggang Ding;Qikeng Xu;Qiang Liu;Yang Zhou
    • Structural Engineering and Mechanics
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    • v.90 no.6
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    • pp.577-590
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    • 2024
  • Considering the Column-Supported Group Silos (CSGSs) often arranged by rows in practical applications, earthquake responses will be affected by group effect. Since group effect presenting uncertainties, establishing the analytic model and evaluating characteristics of CSGSs seems necessary. This study aimed at providing a simplified method to evaluate seismic performances of the CSGSs. Firstly, the CSGSs with different storage granule heights are used as numerical examples to derive the base shear formula for three-particle dynamic analytical model. Then, the base shear distribution coefficient is defined as the group effect index. The simplified calculation method of the group silos based on the distribution coefficients is proposed. Finally, based on the empty, half, and full granular storage conditions, the empirical design parameters for the group silos system are given by combining finite element simulation with shaking table test. The group effect of storage granule heights of group silos on its frequency and base shear are studied by comparative analysis between group silos and independent single silo. The results show that the frequency of CSGSs decreases with the increasing weight of the stored granule. The connection between the column top and silo bottom plate is vulnerable, and structural measures should be strengthened to improve its damage resistance. In case of different storage granule heights, distribution coefficients are effective to reconstruction the group effect. The complex calculations of seismic response for CSGSs can be avoided by adopting the empirical distribution coefficients obtained in this study. The proposed method provides a theoretical reference for evaluation on the seismic performances of the CSGSs.

The Evaluation of Quantitative Accuracy According to Detection Distance in SPECT/CT Applied to Collimator Detector Response(CDR) Recovery (Collimator Detector Response(CDR) 회복이 적용된 SPECT/CT에서 검출거리에 따른 정량적 정확성 평가)

  • Kim, Ji-Hyeon;Son, Hyeon-Soo;Lee, Juyoung;Park, Hoon-Hee
    • The Korean Journal of Nuclear Medicine Technology
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    • v.21 no.2
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    • pp.55-64
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    • 2017
  • Purpose Recently, with the spread of SPECT/CT, various image correction methods can be applied quickly and accurately, which enabled us to expect quantitative accuracy as well as image quality improvement. Among them, the Collimator Detector Response(CDR) recovery is a correction method aiming at resolution recovery by compensating the blurring effect generated from the distance between the detector and the object. The purpose of this study is to find out quantitative change depending on the change in detection distance in SPECT/CT images with CDR recovery applied. Materials and Methods In order to find out the error of acquisition count depending on the change of detection distance, we set the detection distance according to the obit type as X, Y axis radius 30cm for circular, X, Y axis radius 21cm, 10cm for non-circular and non-circular auto(=auto body contouring, ABC_spacing limit 1cm) and applied reconstruction methods by dividing them into Astonish(3D-OSEM with CDR recovery) and OSEM(w/o CDR recovery) to find out the difference in activity recovery depending on the use of CDR recovery. At this time, attenuation correction, scatter correction, and decay correction were applied to all images. For the quantitative evaluation, calibration scan(cylindrical phantom, $^{99m}TcO_4$ 123.3 MBq, water 9293 ml) was obtained for the purpose of calculating the calibration factor(CF). For the phantom scan, a 50 cc syringe was filled with 31 ml of water and a phantom image was obtained by setting $^{99m}TcO_4$ 123.3 MBq. We set the VOI(volume of interest) in the entire volume of the syringe in the phantom image to measure total counts for each condition and obtained the error of the measured value against true value set by setting CF to check the quantitative accuracy according to the correction. Results The calculated CF was 154.28 (Bq/ml/cps/ml) and the measured values against true values in each conditional image were analyzed to be circular 87.5%, non-circular 90.1%, ABC 91.3% and circular 93.6%, non-circular 93.6%, ABC 93.9% in OSEM and Astonish, respectively. The closer the detection distance, the higher the accuracy of OSEM, and Astonish showed almost similar values regardless of distance. The error was the largest in the OSEM circular(-13.5%) and the smallest in the Astonish ABC(-6.1%). Conclusion SPECT/CT images showed that when the distance compensation is made through the application of CDR recovery, the detection distance shows almost the same quantitative accuracy as the proximity detection even under the distant condition, and accurate correction is possible without being affected by the change in detection distance.

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Compression Sensing Technique for Efficient Structural Health Monitoring - Focusing on Optimization of CAFB and Shaking Table Test Using Kobe Seismic Waveforms (효율적인 SHM을 위한 압축센싱 기술 - Kobe 지진파형을 이용한 CAFB의 최적화 및 지진응답실험 중심으로)

  • Heo, Gwang-Hee;Lee, Chin-Ok;Seo, Sang-Gu;Jeong, Yu-Seung;Jeon, Joon-Ryong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.24 no.2
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    • pp.23-32
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    • 2020
  • The compression sensing technology, CAFB, was developed to obtain the raw signal of the target structure by compressing it into a signal of the intended frequency range. At this point, for compression sensing, the CAFB can be optimized for various reference signals depending on the desired frequency range of the target structure. In addition, optimized CAFB should be able to efficiently compress the effective structural answers of the target structure even in sudden/dangerous conditions such as earthquakes. In this paper, the targeted frequency range for efficient structural integrity monitoring of relatively flexible structures was set below 10Hz, and the optimization method of CAFB for this purpose and the seismic response performance of CAFB in seismic conditions were evaluated experimentally. To this end, in this paper, CAFB was first optimized using Kobe seismic waveform, and embedded it in its own wireless IDAQ system. In addition, seismic response tests were conducted on two span bridges using Kobe seismic waveform. Finally, using an IDAQ system with built-in CAFB, the seismic response of the two-span bridge was wirelessly obtained, and the compression signal obtained was cross-referenced with the raw signal. From the results of the experiment, the compression signal showed excellent response performance and data compression effects in relation to the raw signal, and CAFB was able to effectively compress and sensitize the effective structural response of the structure even in seismic situations. Finally, in this paper, the optimization method of CAFB was presented to suit the intended frequency range (less than 10Hz), and CAFB proved to be an economical and efficient data compression sensing technology for instrumentation-monitoring of seismic conditions.

Equine Amniotic Membrane Transplantation in Corneal Perforation Resulting from Melting Ulcer in a Dog (녹는 궤양에 기인한 각막 천공에서 각막 재건을 위한 말양막이식술 증례)

  • Kim, Jury;Bae, Jaehyun;Kwon, Yong-Hwan;Kim, Nam-Soo;Kim, Min-Su
    • Journal of Veterinary Clinics
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    • v.30 no.1
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    • pp.41-44
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    • 2013
  • A 4-year-old castrated male Shih-Tzu was presented to the Chonbuk National University Animal Medical Center with a history of melting ulcer in the right eye (OD). Upon ophthalmologic examination, severe keratomalacia of approximately 70% of the entire surface area with a full thickness corneal defect was found in OD. In addition, iris and fibrin clots were observed on the center of the corneal defect. The menace response and dazzle reflex were normal in OS. As the size and damage of corneal perforation was so severe, amniotic membrane (AM) transplantation was considered to repair the cornea instead of direct suture technique, flap methods or corneal transplantation. Equine AM was sutured to the limbus to cover the entire cornea in a single interrupted pattern using 9-0 nylon suture material. On day 79, mild scarring and pigmentation, with almost no vasculature, remained. The menace response and dazzle reflex were normal of OD. Although pigmentation and scarring remained on the cornea, equine AM transplantation can be useful for reconstruction of severe corneal perforation with keratomalacia.

Channel estimation scheme of terrestrial DTV transmission employing unique-word based SC-FDE (Unique-word 채용한 SC-FDE 기반 지상파 DTV 전송의 채널 추정 기법)

  • Shin, Dong-Chul;Kim, Jae-Kil;Ahn, Jae-Min
    • Journal of Broadcast Engineering
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    • v.16 no.2
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    • pp.207-215
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    • 2011
  • A signal passed through multi-path channel suffers ISI(Inter-Symbol Interference) and severe distortions caused by channel delay spread and noise components at the SC-FDE(Single Carrier with Frequency Domain Equalizer) transmission. Conventional UW(Unique-Word) based SC-FDE iterative channel estimation improves channel estimation performance by smoothing estimated CIR(Channel Impulse Response) of the noise components outside the channel length at time domain and restoring the broken cyclic property through UW reconstruction. In this paper, we propose channel estimation scheme through noise suppression within channel length. To suppress the noise, we estimate noise standard deviation as estimated CIR of the noise components outside the channel length and make criteria of the noise standard deviation gain that doesn't affect the original signal samples. When estimated CIR samples within channel length are less than the criteria value using the noise standard deviation and gain, the noise components are removed. Simulation results show that the proposed channel estimation scheme brings good channel MSE(Mean Square Error) and good BER(Bit Error Rate) performance.

Role of Crural Diaphragm after Esophagogastrectomy (식도-위 절제술 후 횡격막 crura의 역할)

  • 조성래;하현철;이봉근;조봉균
    • Journal of Chest Surgery
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    • v.34 no.10
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    • pp.763-768
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    • 2001
  • Background: The high pressure zone(HPZ) at the gastroesophageal junction is an important barrier for prevention of gastroesophageal reflux. Smooth muscle layers in the lower esophageal sphincter mainly contributes to HPZ at the throacoabdominal junction. The purpose of this study was to investigate the manometric characteristics of the thora-coabdominal junction in patients after surgical removal of the lower esophageal sphincter. Material and Method: Twenty two patients with prior esophagogastrectomy(10 Ivor-Lewis method and 12 left thoracotomy) and 30 normal adults(control group) were studied manometrically. Result: Esophageal manometry showed a HPZ and pressure inversion points distal to the anastomosis in 12 of 22 patients(2 of 10 patients with Ivor-Lewis method and 10 of 12 patients with left thoracotomy) and a HPZ in 30 of 30 normal adults. The location of HPZ front nostril was not significant different between the two groups(42.5$\pm$0.9cm in patients and 43.9$\pm$2.1cm in the control), while the length of HPZ was shorter in patients than in the control(2.13$\pm$0.6cm vs 2.83$\pm$0.59cm). By SPT and RPT, pressures of HPZ at rest were lower in patients(13.78$\pm$1.63mmHg, 28.58$\pm$6.06mmHg) than in control(20.3$\pm$4.95mmHg, 42.80$\pm$15.91mmHg). The HPZ relaxed partially in response to deglutition(84.4% in patient, 90.5% in control group) and contracted in response to increased intra- abdominal pressure induced by leg lifts(HPZ/ Intra-abdominal pressure= 1.81$\pm$0.23 in patient, 2.13$\pm$ 0.58 in control group).

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