• Title/Summary/Keyword: Multiple Defect

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Quantitative Analysis of Artifactual Perfusion Defects due to the Cutoff Frequencies of Reconstruction Filters in Tc-99m-MIBI Myocardial SPECT Images (Tc-99m-MIBI 심근 SPECT에서 재구성필터의 차단주파수에 의한 인위적 관류결손의 정량적 평가)

  • Kwark, Cheol-Eun;Chung, June-Key;Lee, Myung-Chul
    • Journal of Biomedical Engineering Research
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    • v.16 no.2
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    • pp.231-238
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    • 1995
  • Tc-99m-MIBI (Sestamibi) myocardial SPECT along with TI-201 tomographic Imaging has demonstrated wide application and high image quality sufficient for the diagnosis of myocardial perfusion defect, which consequently reflects regional myocardial blood flow. The qualitative values of myocardial SPECT with Tc-99m-MIBI as well ds the quantitative cases depend in some degree on the reconstruction techniques of multiple projections. Filtered backprojection (FBP) Is the common standard method for reconstruction rather than the complicated and time-consuming arithmetic methods. In FBP it is known that the distribution of radioactivity in reconstructed transverse slices varies with the selected litter parameters such as cutoff frequencies and order (Butterworth case) The cutoff frequencies used in clinicAl practice partially remove and decrease the true radioactive distribution and alter the pixel counts, which lead to underestimation of true counts in specific myocardial regions. In this study, we have investigated the effect of cutoff frequencies of reconstruction filter on the artifactually induced perfusion defects, which are often demonstrated near inferior and/or inferoseptal cardiac walls due to the intense hepatic uptake of Tc-99m-MIBI. A computerized method for Identifying the relative degree of artifactual perfusion defect and for comparing those degrees along with the relative amount of hepatic uptake to myocardium was developed and patient images were studied to observe the quantitative degree of underestimation of myocardial perfusion, and to propose some reasonable threshold of cutoff frequency in the diagnosis of perfusion defect quantitatively. We concluded that from the quantitative viewpoint cutoff frequencies may be used as high as possible with the sacrifice of homogeneity of image quality, and those frequencies lower than the common 0.3 Wyquist frequency would reveal severe degradation of radioactive distribution near inferior and/or inferoseptal myocardium when applying Butterworth or low pass filter.

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Antenna Gain Enhancement Using FSS(Frequency Selective Surface) with Defect Mode Characteristic (결함 모드 특성을 갖는 주파수 선택적 표면에 의한 안테나 이득 향상)

  • Kim, June-Hyong;Nam, Sung-Soo;Cho, Tae-Joon;Lee, Hong-Min
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.2
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    • pp.147-153
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    • 2009
  • In this paper, FSS(Frequency Selective Surface) using defect mode characteristic is proposed. The unit cell using defect mode characteristic of the proposed FSS is offered lower resonant frequency in the same cell size. The number of suitable array is optimized 13 by 13. Also, the patch antennas operated in WCDMA(Wideband Code Division Multiple Access) Tx band and Rx band are designed for the comparison. The gain value of proposed FSS-1 complex structure (the patch antenna of Tx band and FSS) is improved 3.3 dB from 9.98 dBi to 13.28 dBi in Tx band. The gain value of proposed FSS-2 complex structure(the patch antenna of Rx band and FSS) is improved 5.53 dB from 9.81 dBi to 15.34 dBi in Rx band. Also the measured impedance bandwidth($VSWR{\leq}2$) of manufactured $13{\times}13$ array antenna is from 337 MHz(1.87 to 2.21 GHz). The measured radiation gain is 11.39 dBi(1.94 GHz), 13.11 dBi(2.05 GHz), 11.09 dBi(2.14 GHz). The measured radiation efficiency is 81 %. Because the proposed FSS structure has more higher gain, it will be applied to antenna of WCDMA repeater system.

Reconstruction of the Large Soft Tissue Defects around Knee Joint with Para-Scapular and Latissimus Dorsi Myocutaneous Free Flap based on Subscapular Vessels (슬관절 주변의 광범위한 연부조직 결손 시에 시행한 광배근-부견갑 피판을 동시에 사용한 유리 피판술의 효과)

  • Chung, Duke-Whan;Lee, Jae-Hoon
    • Archives of Reconstructive Microsurgery
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    • v.11 no.1
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    • pp.11-18
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    • 2002
  • Large soft tissue defects around the knee joint are known to significantly diminish joint function. Severe soft tissue defects on the anterior aspect of the knee joint especially bring on significant joint motion limitation. Although simple split skin grafts can cover the skin defect, the progressing scar contracture of the grafted skin causes joint stiffness. One of the best solutions of large soft tissue defects around the knee joint is covering the defect with a good quality skin flap. Separated flaps with one vascular pedicle are good candidates for covering anterior and posterior aspects of the joint for example. Authors performed 12 cases of combined scapular and latissimus dorsi free flaps from 1984 to 2000. Among them, we experienced 5 cases of knee joint defect covering using the double free flap for coverage of the soft tissue defect with preservation of the knee joint function and satisfactory results. The system of flaps based on the subscapular artery and vein provides a variety of composite free flaps. The possible flaps that can be harvested based on this single vascular pedicle include the scapular and parascapular skin flap, the serratus anterior and latissimus dorsi muscular flap, the lateral scapular bone flap, the latissimus dorsi-rib flap, and the serratus anterior-rib flap. This combined flap is available for multiple tissue defects or complex defects because it can be incorporated with skin, muscle and bone flaps. A main advantage is the independent vascular pedicles of each component, which allow freedom in orientation of each components. Consequently it can be freely applied to any form of three dimensional defects on the upper and lower extremities. The combination of scapular cutaneous flap and latissimus dorsi musculocutaneous flap can be resurfaced for massive cutaneous defects on the extremities. We report the use of the combined scapular and latissimus dorsi free flap in five patients to reconstruct massive defects on the extremities with resultant improved joint function. There was no flap failure and minimal complications and disadvantages. The anatomy of this flap is reviewed and the indication and advantages are discussed. All of the five flaps survived and there was no scar contracture affecting the joint motion.

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Establishment of a deep learning-based defect classification system for optimizing textile manufacturing equipment

  • YuLim Kim;Jaeil Kim
    • Journal of the Korea Society of Computer and Information
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    • v.28 no.10
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    • pp.27-35
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    • 2023
  • In this paper, we propose a process of increasing productivity by applying a deep learning-based defect detection and classification system to the prepreg fiber manufacturing process, which is in high demand in the field of producing composite materials. In order to apply it to toe prepreg manufacturing equipment that requires a solution due to the occurrence of a large amount of defects in various conditions, the optimal environment was first established by selecting cameras and lights necessary for defect detection and classification model production. In addition, data necessary for the production of multiple classification models were collected and labeled according to normal and defective conditions. The multi-classification model is made based on CNN and applies pre-learning models such as VGGNet, MobileNet, ResNet, etc. to compare performance and identify improvement directions with accuracy and loss graphs. Data augmentation and dropout techniques were applied to identify and improve overfitting problems as major problems. In order to evaluate the performance of the model, a performance evaluation was conducted using the confusion matrix as a performance indicator, and the performance of more than 99% was confirmed. In addition, it checks the classification results for images acquired in real time by applying them to the actual process to check whether the discrimination values are accurately derived.

Cleidocranial dysplasia : a case report (쇄골두개이골증의 증례)

  • Kim Jae-Duk;Lee Chang-Yul;You Choong-Hyun
    • Imaging Science in Dentistry
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    • v.34 no.1
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    • pp.55-59
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    • 2004
  • Cleidocranial dysplasia is a rare and autosomal dominent disorder characterized by aplasia or hypoplasia of the clavicles, an open fontanelle, dental abnormalities, and short stature, A 17-year-old female who presented with short stature and subsequent delay in eruption of permanent teeth is described. she showed the abnormal hypermobility of the shoulder, ocular hypertelorism and concave nasal bridge. Radiographs revealed the underdeveloped maxilla, defect of the cranium in the fontanelle region, and aplasia of the clavicles. Characteristically, panoramic view revealed near parallel-sided borders of the ascending ramus and downward curvature of the zygomatic arch with hypoplasia. The prolonged retention of deciduous teeth with delayed eruption of permanent teeth and multiple embedded supernumerary teeth were striking. Radiographic and clinical investigations revealed Cleidocranial dysplasia.

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Critical Review of Current Trends in ASIC Writing and Layout Analysis

  • Vikram, Abhishek;Agarwal, Vineeta
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.16 no.2
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    • pp.236-250
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    • 2016
  • Electrical Designs for Application Specific Integrated Circuits (ASIC) has undergone a change recently with the advent of the sub-wavelength lithography. The optical projection with 193 nm wavelength has been further extended with the use of immersion and other techniques. The competing trends for printing smaller design features have been discussed in this paper with the discussion of the electrical layout analysis to find unfriendly design features. The early knowledge of the unfriendly design features allows remedial actions in time for better yield on the wafer. There are existing standard design qualification criteria being used in the design and fabrication community, but they seem to be insufficient to guarantee defect free designs. This paper proposes an integrated approach for screening the layout with multiple aspects: layout geometry based, graphical analysis and process model based verification. The results have been discussed with few example design features from the 28nm design layout.

The treatment of lower extremity defects with severe proliferative tissue using an adjustable horizontal mattress suture in a Tosa dog

  • Heo, Suyoung;Kim, Namsoo
    • Korean Journal of Veterinary Research
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    • v.54 no.2
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    • pp.121-122
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    • 2014
  • A 2-year-old male Tosa was admitted for treatment of a non-healing wound on the right forelimb. Skin tests were unremarkable; however, the lesion contained severe proliferative tissue. Surgical treatment was conducted due to the extensive skin defect and granulation tissue present. Following removal of the proliferative tissue, the wound was closed using the adjustable horizontal mattress suture method with multiple punctate relaxing incisions. The proliferative tissue healed completely after the surgical treatment. This technique can be considered an alternative treatment for the proliferative tissue when conditions require a skin graft or flap after surgical treatment.

Paraesophageal Hernia with Gastric Erosion - A Case Report - (식도주위 열공 탈장에서 병발한 위미란의 치험)

  • Baek, Hong-Gyu;Yu, Hoe-Seong
    • Journal of Chest Surgery
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    • v.26 no.4
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    • pp.337-341
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    • 1993
  • Since the first deliberate repair of hiatal hernia by Wm. J. Mayo in 1911, counterless procedure have been performed to correct herniation of the stomach into the posterior mediastinum. Recently,we experienced 51 years old female patient with large paraesophageal hernia and complete intrathoracic stomach which combined with multiple gastric erosion with chronic blood loss. So gastric ulcer within a diaphragmatic hernia is a distinct physiophathologic and clinical entity that our patient suffered from severe anemia due to chronic blood loss. The hernia was repaired transabdominally including reduction of stomach, excision of sac, closure of defect, anterior gastropexy, and gastr6stomy. Because of absent gastroesophageal refiux, no another antireflux procedure was required and erosion was managed by H2 receptor blocker.

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Staged Total Correction of Complexes Anomalous Origin of Right Pulmonary Artery from the Ascending Aorta One Case Report (상행 대동맥에서의 우폐동맥 이상기시증을 동반한 복잡 심기형의 단계적 완전 교정술-1례 보고-)

  • 정일상;한재진
    • Journal of Chest Surgery
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    • v.30 no.3
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    • pp.322-325
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    • 1997
  • We experienced a case of anomalous origin of right pulmonary artery from the ascending aorta associated with pulmonary atresia, ventricular septal defect, absence of left pulmonary artery afld multiple major aortopulmonary collateral artery (MAPCA). At ten month of age, left pulmonary artery creation with unifocalization and right pulmonary artery banding were performed as the Urst stage, followed by coil embolization of right MAPCA 1 month later, and 1 year later, the total correction was done. After total repair, the patient showed good postoperative course and excellent angiographic and hemodynamic results at 1 year follow-up study.

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A Model for Determining Optimal Input Quantity in a Semiconductor Production Line Considering Yield Randomness and Demand Uncertainty (불확실한 수율과 수요를 고려한 반도체 생산라인에서의 최적 투입량 결정모형)

  • 박광태;안봉근
    • Journal of the Korean Operations Research and Management Science Society
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    • v.20 no.1
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    • pp.27-34
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    • 1995
  • In this paper, we have developed a model to determine the input quantity to be processed at each stage of a multi-stage production system in which the yield at each stage may be random and may need reworking at this stage. Yield randomness. especially in a semiconductor industry, is a most challenging problem for production control. The demand for flnal product is uncertain. We have extended the model proposed in Park and Kim[9] to consider a multiple number of reworkings which can be done at any stage prior to or tat the stage whose output in bad, depending on the level of the defect.

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