• Title/Summary/Keyword: Defect Imaging

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Control of surface defects on plasma-MIG hybrid welds in cryogenic aluminum alloys

  • Lee, Hee-Keun;Chun, Kwang-San;Park, Sang-Hyeon;Kang, Chung-Yun
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.7 no.4
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    • pp.770-783
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    • 2015
  • Lately, high production rate welding processes for Al alloys, which are used as LNG FPSO cargo containment system material, have been developed to overcome the limit of installation and high rework rates. In particular, plasma-metal inert gas (MIG) hybrid (PMH) welding can be used to obtain a higher deposition rate and lower porosity, while facilitating a cleaning effect by preheating and post heating the wire and the base metal. However, an asymmetric undercut and a black-colored deposit are created on the surface of PMH weld in Al alloys. For controlling the surface defect formation, the wire feeding speed and nozzle diameter in the PMH weld was investigated through arc phenomena with high-speed imaging and metallurgical analysis.

Double Outlet Right Ventricle in a Cat

  • Hwang, Tae-sung;Noh, Seul-ah;Yoon, Young-min;Yeon, Seong-chan;Lee, Hee-Chun
    • Journal of Veterinary Clinics
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    • v.33 no.5
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    • pp.307-309
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    • 2016
  • A 10-month-old intact male Scottish Fold was presented with cardiomegaly. The cat showed exercise intolerance after birth. Radiographs showed cardiomegaly with bulging of the main pulmonary artery and dilation of pulmonary arteries. Echocardiogram revealed abnormally arisen aortic root toward right ventricle with left-to-right shunted perimembraneous ventricular septal defect located underneath the aortic root. Based on imaging studies, the cat was diagnosed as subaortic type of double outlet right ventricle (DORV) without concurrent abnormalities.

Condylar jugular diverticulum: A report of 3 cases

  • Jagtap, Rohan;Wazzan, Taggreed;Hansen, Matthew;Kashtwari, Deeba
    • Imaging Science in Dentistry
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    • v.49 no.3
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    • pp.251-256
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    • 2019
  • Jugular bulb diverticulum is an irregular extension of the jugular bulb into the temporal bone that may be symptomatic or asymptomatic. The jugular bulb has rarely been reported to extend into the occipital condyle; such extension is termed a condylar jugular diverticulum and is characterized as a defect in the occipital condyle contiguous with the jugular bulb. This report details 3 cases of condylar jugular diverticulum. Extension of the jugular bulb into the ipsilateral occipital condyle was noted as an incidental finding on cone-beam computed tomographic (CBCT) images of 3 patients. All 3 patients were asymptomatic, and this finding was unrelated to the initial area of interest. CBCT use is becoming ubiquitous in dentistry, as it allows 3-dimensional evaluation, unlike conventional radiography. Proper interpretation of the entire CBCT is essential, and recognition of the indicators of condylar jugular diverticulum may prevent misdiagnosis of this rare entity.

Case report of cerebral creatine deficiency syndrome with novel mutation of SLC6A8 gene in a male child in Bangladesh

  • Rahman, Muhammad Mizanur;Fatema, Kanij
    • Journal of Genetic Medicine
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    • v.18 no.1
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    • pp.44-47
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    • 2021
  • Cerebral creatine deficiency syndrome (CCDS) is a disorder where a defect is present in transport of creatine in the brain. Creatine plays an essential role in the energy metabolism of the brain. This is a genetic disorder, autosomal recessive or X linked, characterized by intellectual disability, speech and language delay, epilepsy, hypotonia, etc. Until recently very few number of cases have been reported. Here we report a case of 1.5-year-old boy who had epilepsy (epileptic spasm and generalized tonic clonic seizure), intellectual disability, microcephaly, hypotonia and speech delay. His magnetic resonance imaging of brain showed cortical atrophy and electroencephalography showed burst suppression pattern. The diagnosis was confirmed by clinical exome sequencing which showed novel mutation of SLC6A8+ in exon 9, suggestive of X linked recessive CCDS. The patient was then treated with glycine, L-arginine and creatine monohydrate with multiple antiepileptic drugs.

Clinical evaluation and surgical intervention for diaphragmatic eventration mimicking peritoneopericardial hernia in a cat

  • Min-Jung Ko;Kyoung-Min Song;Hun-Young Yoon
    • Journal of Veterinary Science
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    • v.25 no.2
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    • pp.19.1-19.6
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    • 2024
  • A 2-year-old spayed female British Shorthair cat presented with an increased frequency and duration of cough since infant period. Based on radiographic, ultrasonographic, and computed tomography findings, peritoneopericardial diaphragmatic hernia was considered so that repair surgery was planned. During celiotomy, lax diaphragm was identified instead of defect. Transabdominal diaphragmatic plication was performed to resolve lax diaphragm and to prevent recurrence by overlapping relatively normal part of diaphragm. Diagnosed with diaphragmatic eventration postoperatively, the cat showed improvement in clinical signs and imaging results. Transabdominal diaphragmatic plication is a suitable treatment; the patient maintained normally during a 14-month follow-up period.

Arthroscopic treatment of chronic calcific tendinitis with intraosseous migration: a case report

  • Jung Uk Kim;Pei Wei Wang
    • Clinics in Shoulder and Elbow
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    • v.27 no.2
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    • pp.263-266
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    • 2024
  • We present a case of calcific tendinitis in the shoulder, where calcifications were observed within both the tendon and the adjacent bone. At the time of acute onset, radiographs (including a plain radiograph) and magnetic resonance imaging revealed calcific tendinitis with intraosseous migration. The patient's symptoms did not improve after 5 months of conservative treatment. The patient underwent arthroscopic debridement of the calcific deposits, and the defect was repaired using the double-row repair technique. The patient's symptoms improved 3 months after arthroscopic treatment. We share our unusual experience with arthroscopic debridement in the treatment of chronic calcific tendinitis with intraosseous migration.

Tension Pneumocephalus Secondary to Frontal Sinusotomy in a Dog

  • Seoyeoun Ji;Hyung-Kyu Chae;Yeon-Jung Hong
    • Journal of Veterinary Clinics
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    • v.41 no.4
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    • pp.223-227
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    • 2024
  • Air accumulation in the cranial cavity is referred to as pneumocephalus. Tension pneumocephalus is a neurosurgical emergency that can cause headaches, seizures, reduced consciousness, and even death owing to increased intracranial pressure. We report a case of tension pneumocephalus. The patient underwent a frontal sinusotomy for a mass invading the frontal sinus and nasal cavity. One month later, the patient was admitted to the emergency room with seizures and neurotic symptoms, and computed tomography (CT) revealed tension pneumocephalus with significant gas dilatation of both lateral ventricles. Prompt treatment of the dural defect resulted in the immediate improvement of neurological signs. A CT re-examination 1 week after surgery showed that the pneumocephalus had completely resolved. Tension pneumocephalus should be considered a potential complication in patients with worsening neurological signs after skull base surgery. An accurate diagnosis requires an understanding of imaging features and a high index of suspicion, and immediate intervention is essential.

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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Internal Defection Evaluation of Spot Weld Part and Carbon Composite using the Non-contact Air-coupled Ultrasonic Transducer Method (비접촉 초음파 탐상기법을 이용한 스폿용접부 및 탄소복합체의 내부 결함평가)

  • Kwak, Nam-Su;Lee, Seung-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.11
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    • pp.6432-6439
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    • 2014
  • The NAUT (Non-contact Air coupled Ultrasonic Testing) technique is one of the ultrasonic testing methods that enables non-contact ultrasonic testing by compensating for the energy loss caused by the difference in acoustic impedance of air with an ultrasonic pulser receiver, PRE-AMP and high-sensitivity transducer. As the NAUT is performed in a state of steady ultrasonic transmission and reception, testing can be performed on materials of high or low temperatures or specimens with a rough surface or narrow part, which could not have been tested using the conventional contact-type testing technique. For this study, the internal defects of spot weld, which are often applied to auto parts, and CFRP parts, were tested to determine if it is practical to make the NAUT technique commercial. As the spot welded part had a high ultrasonic transmissivity, the result was shown as red. On the other hand, the part with an internal defect had a layer of air and low transmissivity, which was shown as blue. In addition, depending on the PRF (Pulse Repetition Frequency), an important factor that determines the measurement speed, the color sharpness showed differences. With the images obtained from CFRP specimens or an imaging device, it was possible to identify the shape, size and position of the internal defect within a short period of time. In this paper, it was confirmed in the above-described experiment that both internal defect detection and image processing of the defect could be possible using the NAUT technique. Moreover, it was possible to apply NAUT to the detection of internal defects in the spot welded parts or in CFRP parts, and commercialize its practical application to various fields.

SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY FINDINGS IN TOURETTE'S AND CHRONIC MOTOR TIC DISORDER (뚜렛씨병과 만성틱장애의 단일광자방출전산화단층촬영 소견에 관한 연구)

  • Cho, Soo-Churl;Lee, Myung-Chul;Kim, Ja-Sung
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.4 no.1
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    • pp.68-78
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    • 1993
  • The pathophysiology and neural mechanism involved in Tourette's and chronic motor tic disorder are highly controversial. In order to investigate the functional abnormalities of brain. In Tourette's and chronic motor tic disorder, 42 children with Tourette's and chronic motor disorder underwent single photon emission computed tomography(SPECT) using Tc-99m-HM-PAO. The results are summarized as follows : 1) 31.0% (13/42) of this series revealed perfusion defect in cerebral cortex. 2) 4.8% (2/42) revealed perfusion defect in basal ganglia. 3) 4.8(2/42) revealed perfusion defect in thalamus. 4) 16.7%(7/42) showed perfusion defect in cerebellum. 5) The frequency of abnormal perfusion showed no significant difference between tic with and without attention deficit hyperactivity disorder. 6) The frequency of abnormal perfusion showed no significant difference between Tourette's and chronic motor tic disorder. These findings support the hypothesis of a possible involvement of brain dysfunction in the production of Tourette's and chronic motor tic disorder, and quantification of blood flow and co-registration with magnetic resonance imaging will increase the validity of this study.

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