• Title/Summary/Keyword: 에코

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MR spectroscopy using single-shot RF localization technique (단일 RF 펄스를 사용한 3차원 체적 선택 방법을 이용한 MR 스펙트로 스코피)

  • Rim, C.Y.;Chun, K.W.;Ra, J.B.;Cho, Z.H.
    • Proceedings of the KOSOMBE Conference
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    • v.1989 no.05
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    • pp.51-54
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    • 1989
  • In last several years, a number of volume localization techniques, such as ISIS, VSE, SPARS and STEAM etc., have been developed for the MR spectroscopy. These localizing techniques, however, require application of several RF pulses for the 3-D volume selection and suffer from T1 and T2 decays due to relatively long RF excitation time. In this paper, we propose a single-shot RF pulse localization technique to achieve the localized 3-D volume selection. This technique combines the cylindrical volume selection technique with a radial gradient coil with single-shot RF pulse and the oscillating selection gradient technique, so thai it minimizes the volume selection time. We report some experimental results obtained with the proposed method which appears promising for 3-D volume imaging and localized spectroscopy.

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Prognostic Value of Computed Tomography and Gradient-echo Magnetic Resonance Imaging in Diffuse Axonal Injury (미만성 축삭 손상에서 전산화단층촬영과 경사에코 자기공명영상을 이용한 예후의 평가)

  • Jung, Nam-Ki;Jin, Sang-Chan;Choi, Woo-Ik
    • Journal of Trauma and Injury
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    • v.25 no.4
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    • pp.122-131
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    • 2012
  • Purpose: Diffuse axonal injury (DAI) is clinically defined as a coma of over six hours in a head trauma victim without a focal mass lesion. The emergency physician usually resuscitates and stabilizes a comatose head trauma victim in the emergency Department. After assessment and treatment, the prognosis is very important to both the victim and the physician. The prognosis for DAI is based on Glasgow Coma Scale (GCS) and other imaging data. We investigated the prognostic value of computed tomography (CT) and gradient-echo magnetic resonance imaging (GRI) for head trauma victims with DAI. Methods: Fifty-three(53) head trauma victims of DAI were enrolled in this study from 2007 to 2012. During the study period of six years, data on trauma victims were collected retrospectively. We analyzed the differences in the Glasgow Outcome Scale (GOS) result between the CT and the GRI modalities. Results: We classified the study group by using GOS. Between the good outcome subgroup (GOS scores of 4 and 5) and the poor outcome subgroup (GOS score of 1-3), there were no statistical difference in sex, age, initial vital signs and initial GCS score. The good outcome subgroup had non-hemorrhage on CT(52%), which was correlated with good outcome and a shorter awakening time, while a larger number and a deeper location of hemorrhagic lesions on in GRI were correlated with poor outcome in DAI. Conclusion: We conclude that the existence of hemorrhagic lesions on CT, and the number and location of those lesions on GRI had good prognostic value for head trauma victims with DAI.

Imaging Features of the Intra-abdominal Granulomas in Two Cases (두 케이스에서 복강내 육아종의 영상학적 특징)

  • Choi, Mi-Hyun;Chang, Jin-Hwa;Lee, Hye-Yeon;Kim, Jun-Young;Kim, Wan-Hee;Yoon, Jung-Hee;Choi, Min-Cheol
    • Journal of Veterinary Clinics
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    • v.27 no.3
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    • pp.302-306
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    • 2010
  • One dog and a cat with a history of diarrhea, anorexia and depression were referred. They showed normal laboratory examination results. Radiographic findings included a mid abdominal mass with ill-defined margin and serosal detail loss of peritoneal space. On abdominal ultrasonography, the round mass with heterogenous parenchymal echogenicty with irregular contour was found. It revealed as inflammation through ultrasound guide fine needle aspiration. After surgical removal of the masses in both cases, the clinical signs were resolved and focal pyogranuloma was confirmed through histopathologic examinations.

Surgical Role of the Treatment of the Patients with Infective Endocarditis in Childhood (아동기 전염성 심내막염 환자치료의 외과적 역할)

  • 김경환;서경필
    • Journal of Chest Surgery
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    • v.30 no.12
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    • pp.1175-1183
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    • 1997
  • Background. Infective endocarditis s an uncommon but serious disease in children. Optimal treatment strategy, especially surgical indications, continues to evolve. Method. In this report, we retrospectively reviewed 19 patients who underwent operations in Seoul National University Children's Hospital for infective endocarditis between September 1986 and February 1996. There were 8 male and 11 female patients(mean age 70.6 months) and their main symptoms were fever and dyspnea. Preoperative echocardiography detected vegetation in 14 cases out of 19. Congenital anomalies were in 15 cases and acquired forms were in 4 cases. Causative organisms were identified in 12 cases and Gram-positive cocci were in 7 cases. Adequate preoperative antibiotic management was done. Result. With cardiopulmonary bypass in all cases, surgical corrections including vegetation removal were performed. 4 patients died after operations(21.1%). All the mortality cases were having underlying complex cardiac anomalies. There were no late deaths. Act arial survival rate was 79.0% at 1 year and 79.0% at 5 year and reoperationfree survival rate was 73.7% at 1 year and 73.7% at 5 year. Collclusion. Despite advances in antibiotic therapy, early surgical treatment is imperative in a significant subset, and concurrent intracardiac repair should be appropriate.

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Change in Ultrasonic Characteristics with Isothermal Heat Treatment of 2.25Cr-1Mo Steel (등온열처리에 따른 2.25Cr-1Mo강의 초음파 특성 변화)

  • Nam, Young-Hyun;Baek, Un-Bong;Park, Jong-Seo;Nahm, Seung-Hoon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.37 no.3
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    • pp.353-358
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    • 2013
  • The ultrasonic characteristics of 2.25Cr-1Mo steel were investigated in relation to the isothermal heat treatment temperature and time. Charpy impact tests and hardness tests were conducted on individual specimens with three different heat treatment conditions. A pulse-echo method with longitudinal waves was used to measure the attenuation and velocity of ultrasonic waves. The FATT (fracture appearance transition temperature) increased with an increase in the isothermal heat treatment time, which implies that the toughness decreased. As the isothermal heat treatment time and temperature increased, the longitudinal wave velocity and ultrasonic attenuation coefficient were raised.

Measurements of Ultrasonic Velocity and Attenuation by Signal Processing Techniques in Time and Frequency Domains (시간 및 주파수 영역에서의 신호 처리 기술에 의한 초음파 속도와 감쇠의 측정)

  • Jang, Young-Su;Kim, Jin-Ho;Jeong, Hyun-Jo;Nam, Young-Hyun
    • Journal of the Korean Society for Nondestructive Testing
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    • v.19 no.2
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    • pp.118-128
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    • 1999
  • There are many ultrasonic measurement methods that are used in nondestructive testing applications. Some typical applications include material property determination, microstructural characterization. and flaw detection. Ultrasonic parameters such as velocity and attenuation are most commonly required in these applications. The accuracy and repeatability of testing results are dependent on both the hardware used to generate and receive the ultrasonic waves and on the analysis software for calculating these parameters. In this study, five analysis algorithms were implemented on a computer for measuring wave speed in a pulse echo. immersion testing configuration. In velocity measurements comparisons were made between the overlap. cross-correlation. Fourier transform. Hilbert transform, wavelet transform algorithms. Velocity measurement was applied to an isotropic steel sample using the five analysis algorithms. Frequency-dependent phase/group velocity and attenuation were also measured using the Fourier transform and wavelet transform algorithms on a composite laminate containing voids.

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Analysis of Ultrasonic Scattering from Side-drilled Holes (원주형 기공에 대한 초음파 산란 해석)

  • Jeong, Hyun-Jo;Park, Moon-Cheol
    • Journal of the Korean Society for Nondestructive Testing
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    • v.24 no.6
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    • pp.559-565
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    • 2004
  • Two different methods were used for the scattering analysis of side-drilled holes(SDH). The scattering models include an explicit model based on the Kirchhoff approximation and the solution of the exact separation of variables. The far-field scattering amplitude was calculated and their time-domain results were compared for the case of shear vertical wave. The exact solution predicts the existence of the creeping wave. The Kirchhoff approximation agreed to the exact solution, except the case of the creeping wave. Two measurement models were introduced to predict the response from the SDHs for the case of immersion, pulse-echo testing. The received voltage was calculated for the case of the shear vertical waves with the incident angle of $45^{\circ}$ to the SDH with the diameter of 1mm, and compared with the experimental results.

Eco-Fashion Industry Trend and Creative Fashion Design Technic for Zero-Waste (친환경 패션산업 동향과 쓰레기 발생 감량화(Zero Waste)를 위한 실험적 디자인 사례 연구)

  • Park, Hye-Won
    • Journal of Fashion Business
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    • v.16 no.4
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    • pp.29-45
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    • 2012
  • The purpose of this study is for providing not only the latest design technique trend for zero waste fashion, but information about creative fashion design education through eco-fashion industry trend in globally and domestic which is focusing on eco-fashion labelling. The research were processed with literature related eco, sustainable, green fashion books, former articles, newspapers, and web sites. The results as follows; The certification about eco-fashion product is moving to 'Life Cycle Assessment' from focused on primary process like material, finishing, dyeing. Especially simplicity of process means reducing the wastes. And fabric wastage for adult outwear was estimated 15% percent of total fabric used in general design studios. Three cases for Zero waste fashion were as follows; First, Jigsaw puzzle by Timo Rissane and Mark Liu were different zero waste methods, but the result was same. Rissene's method was based on traditional cutting like 'cut and sew' but traditional cutting can lead to design that have an abundance of fabric and drape. Jigsaw of Rissene was approached with description a pattern-cutting technique in which all piece interlock with each other generating no waste from design production. Another Jigsaw by Liu was related with innovative textile design. DTP makes the possibilities for zero waste garment production almost endless. The dress intricately cut from 10 pieces, wastes none of the fabric required to make it. Second, Subtraction Cutting by Julian Roberts provides unexpected fluid, organic forms and zero waste fabric. Utilizing Roberts plug(tunnel) technique enables any part of the garment that is removed for fit or aesthetics to be reincorporated into the design of garment. Third was 'Bio Couture' by Suzanne Lee. She has created garments from cellulose bacteria which grow in a bathtub using only green methods addressing in such as way ecological issues and exploring the future of fashion design in conjunction with technology.

Superficial Necrolytic Dermatitis (Hepatocutaneous Syndrome) in a Dog with History of Long-Term Phenobarbital Administration (개에서 페노바비탈 장기 투여로 유발된 표재성 괴사성 피부염 1례)

  • Chung, Tae-Ho;Kim, Ji-Hyun;Nam, Eui-Hwa;Kim, Dae-Yong;Kim, Hyung-Jin;Choi, Min-Cheol;Youn, Jung-Hee;Youn, Hwa-Young;Hwang, Cheol-Yong
    • Journal of Veterinary Clinics
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    • v.27 no.4
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    • pp.445-449
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    • 2010
  • A dog with a history of long-term phenobarbital administration presented to Seoul National University Hospital for Animals with clinical signs of footpad ulceration and facial ulcerative dermatitis. Skin lesions (facial/footpad dermatitis), histopathologic signs (parakeratotic hyperkeratosis, edema and hyperplasia of the epidermis), and liver involvement (increased plasma liver enzymes and nodular lesions) suggested a diagnosis of superficial necrolytic dermatitis (SND). The patient died suddenly at home of unknown cause after 8 months medical treatment, but intravenous amino acid supplementation and supportive hepatic medication proved as effective for the skin conditions.

Experimental Study of Chemical Shift Artifacts at 1.5T and 3.0T MRI using Gradient Echo Pulse Sequence (GE 펄스시퀀스을 이용한 1.5T와 3.0T MRI의 화학적 이동 인공물의 실험적 연구)

  • Cheol, Kweon Dae
    • Journal of the Korean Society of Radiology
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    • v.10 no.7
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    • pp.531-537
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    • 2016
  • An experimental study was to use the parameter to determine the MRI artifact of chemical shift that occurs in water and fats. Scanning the image according to the encoding parameter and the bandwidth and change in 1.5T and 3.0T MRI to the SNR, we compared the CNR. In the image was confirmed that the occurrence of artefacts in the chemical shift of the water and oil. 3.0T more image artifacts in the 1.5T was confirmed that the relatively reduced. The width of the bandwidth it could be confirmed that according to the honeycombs artifacts decrease. Therefore, in order to reduce the artifacts in the MRI scan of the chemical shift runners weak field strength, is thought to be appropriate to widen the width of the bandwidth.