• Title/Summary/Keyword: resonance test

Search Result 983, Processing Time 0.029 seconds

Demand Surveys for Big Research Facilities and Equipments to Advance National S&T Research Infrastructure (과학기술 하부구조 선진화를 위한 대형 연구장비의 수요 조사)

  • 권용수;민철구
    • Proceedings of the Technology Innovation Conference
    • /
    • 1997.12a
    • /
    • pp.159-176
    • /
    • 1997
  • This paper deals with demand surveys for big science and technology research facilities and equipments to advance national S'||'&'||'T research infrastructure. We perform surveys thrice based on applied Delphi method on the future demand of big S'||'&'||'T research facilities and equipments among Korean scientists and engineers. We employ the concept of big S'||'&'||'T research facilities and equipments as follows: \circled1 The operating size of it is equivalent to that of an institute or research center, and/or \circled2 The users in various disciplines are many, and/or \circled3 The application areas or spill-over effects are large, and/or \circled4 The scale and scope of research objects is equivalent to that of mega science area such as earth.oceanography.space, and/or \circled5 The expenses for installing and operating it are to be supported by government, and/or \circled5 The facilities are expected as necessary for international joint research, and/or \circled7 It is necessary for promoting creative basic science and developing creative technology. We ask the respondents to answer the following questionnaire: - How to prioritize the equipments according to the degree of importance\ulcorner $\square$ Promotion of basic science and mega science, the development of the technologies to enhance the public welfare, the competitiveness of industrial technologies, the job creation for the S'||'&'||'T personnel, and international cooperation. - Who should be in charge of acquisition and operation of the equipments\ulcorner $\square$ Industry, Government Research Institutes, Academy, ERC and SRC. - When shall we acquire the equipment\ulcorner $\square$ Within 2000, 2002, 2007, 2012, and 2017. - How shall we acquire the equipments\ulcorner $\square$ International Joint Development, Domestic Development, Acquisition from Overseas, - How much will the equipment generate spill-over effects to national competitiveness\ulcorner $\square$ Promotion of basic science, contribution to the economy, supply of S'||'&'||'T personnel, and international cooperation. We suggest the following equipments as prioritized candidates after consulting the officers from MOST, MOE, MIC, MOEN and experts from KBSI and STEPI:(table omitted) where, #1, Korea Advanced Liquid Metal Reactor, #2. 800 MHz Superconduction Fourier-Transform Nuclear Magnetic Resonance Spectrometer, #3. Ion Accelerator, #4. Seismic Test Facility, #5. Transonic Wind Tunnel, #6. Radio Telescope for Very Long Baseline Interferometer, #7. 3000t Universal(or Large Structure) Testing Machine, #8. Compost Facility or Plasma Pyrolysis Facility.

  • PDF

Idiopathic Vestibular Disease in a Beagle Dog: Clinical Findings and Outcome (비글 견에서 발생한 특발성 전정계 질병 증례: 임상적 발견과 결과)

  • Kang, Byeong-Teck;Jung, Dong-In;Park, Chul;Gu, Su-Hyun;Jeon, Hyo-Won;Park, Hee-Myung
    • Journal of Veterinary Clinics
    • /
    • v.23 no.3
    • /
    • pp.340-343
    • /
    • 2006
  • A 10-year-old, intact female Beagle dog was presented for examination of acute onset of right-sided head tilt and moderate ataxia. Clinical signs were acutely presented 12 days ago and had been progressively alleviated until the admission day. The dog was bright, alert, and responsive. On neurological examinations, mild head tilt to the right and mild ataxia were noted, thus vestibular disorders were suspected. Central vestibular disease was ruled out based on the clinical signs, magnetic resonance imaging(MRI), and cerebrospinal fluid(CSF) analysis. Otoscopic examination showed that the tympanic membranes were intact and normal in appearance. On radiographic and MR examinations, abnormalities were not found in the tympanic bulla and the petrous portion of the temporal bone. Hypothyroidism was ruled out by thyroid-stimulation hormone(TSH) stimulation test. Clinical signs were completely disappeared at 2 weeks after discharge without any therapy. Thus, the dog was definitively diagnosed as idiopathic vestibular disease based on the clinical signs, excluding other causes of vestibular dysfunction, and the alleviation of clinical signs with time.

A Study on Clinical Findings about Vertebral Disease Diagnosed with MRI (MRI로 진단된 척추질환의 임상적 소견)

  • Kim, Ham-Gyum
    • Journal of radiological science and technology
    • /
    • v.29 no.3
    • /
    • pp.157-165
    • /
    • 2006
  • In order to analyze clinical characteristics like sex- and age-based onset frequency and onset region from vertebral disease cases, this study investigated total 1,291 cases of vertebral disease that were diagnosed via magnetic resonance imaging(MRI) from January to December 2004 at B University Hospital in metropolitan area. For higher diagnostic accuracy in cases of spinal disorder diagnosed, this study analyzed findings from data reading conducted by veteran specialists in diagnostic radiology. But this study excluded uncertain lesion cases, the cases requiring differential diagnosis from other disorders and so on from subjects under analysis. This study employed superconductive 1.5 Tesla SIGNA MR/i for MRI test and basically received resulting images via FSE(fast spin echo). In particular, this study obtained T1 and T2 myelogram with regard to regional characteristics(such as cervical vertebrae, thoracic vertebrae and lumbar vertebra) and imaging characteristics for sagittal and transverse section. As a result, this study came to the following conclusions : 1. In terms of general characteristics of subjects under analysis, male group comprised 53.5% and female 46.5% out of total 1,291 subjects. 2. The regional onset frequency of spinal disorders was converged primarily on lumbar vertebra(65.5%), which was followed by cervical vertebrae(27.3%) and thoracic vertebrae(7.0%) respectively. 3. Top 10 cases with high onset frequency of spinal disorders can be listed as follows : 1) posterior bulging disc 65.8% 2) narrowing of neural foramen 23.8% 3) herniated intervertebral disc (HIVD) 22.4% 4) spinal stenosis 16.7% 5) osteochondrosis 6.4% 6) compression fracture 6.4% 7) facet joint arthropathy 6.2% 8) spondylolisthesis 6.0% 9) spinal cord tumor 3.5% 10) inter body fusion 2.6%

  • PDF

A Study on Indirect Attachment Method of Compensation Materials to Increase Signal Intensity in Magnetic Resonance Imaging (자기공명영상검사 시 신호강도를 높이기 위한 보상물질의 간접부착 방식에 관한 연구)

  • Son, Soon-Yong
    • The Journal of the Korea Contents Association
    • /
    • v.17 no.7
    • /
    • pp.437-442
    • /
    • 2017
  • Previously, studies on compensation material to increase the signal intensity have been conducted which does not affect the reading of images. However, the compensation material has a concern on patient infection as it is attached directly on the skin. Therefore, in this study, we tested an indirect attachment of the compensation material as an alternative method of the direct attachment. The silicon compensation material was fabricated in the form of a cylindrical bar and attached to each element of the 8 channel head coil. Then the signal intensities of the water phantom pre and post application of the silicon were measured. T1 and T2-weighted images were acquired using an 8-channel head coil and a 3.0T superconducting MRI. Signal intensities were measured by using an image measuring program. Paired t-test was used to verify if there were significant differences. The signal intensity before application of the silicon was significantly increased by 3.39% and 2.62% in T1 and T2 weighted images, respectively. Although the indirect attachment method had a limitation to completely replace the existing method, it was considered to be useful in patients with infectious diseases such as diabetic complications since it had a meaningful improvement in signal intensity based on the filling factor increase.

Treatment Outcome and Prognostic Factors of Cushing's Disease in Adults (성인 쿠싱병의 치료성적과 예후인자)

  • Park, Chul-Kee;Hwang, Sung Kyun;Gwak, Ho-Shin;Yoo, Heon;Chung, Young Seob;Paek, Sun Ha;Kim, Dong Gyu;Jung, Hee-Won;Kim, Seong Yeon;Hong, Seung Kuan
    • Journal of Korean Neurosurgical Society
    • /
    • v.29 no.10
    • /
    • pp.1316-1321
    • /
    • 2000
  • Objectives : The authors analyzed the surgical series of Cushing's disease to evaluate the proper treatment policy and to verify the possible prognostic factors. Material and Methods : Of 50 patients diagnosed as Cushing's disease and operated at Department of Neurosurgery of our institute between 1988 and 1999, 48 patients with available medical records were analyzed retrospectively. Mean follow-up period was 48 months(3 to 109 months). Preoperative diagnosis was made after evaluating the patients with multiple-stage endocrinological studies and 31 selective patients were evaluated with inferior petrosal sinus sampling(IPSS). Magnetic resonance imaging(MRI) and/or high resolution computerized tomography(CT) was done in all patients. A total of 51 transsphenoidal adenomectomy(TSA) were performed including 3 revision for initial surgical failure cases. Remission was decided on the basis of both endocrinological criteria and clinical status. Radiation and/or ketoconazole therapy were applied to failed cases. For the verification of prognostic factors, the authors evaluated the statistical significance of multiple variables over remission rate by chi-square test. Result : Sensitivity of IPSS for central localization was 93.5% which was better than that of MRI(87.5%). But for lateralization, it was 72.4% for IPSS versus MRI 90.5%. Success rate of TSA was 82%(42/51) and recurrence rate was 9%(4/48). When including adjuvant treatments for surgically failed cases, overall success rate was 89.6% and all of 3 reoperated cases(TSA) due to recurrence were successful. Significant complication occurred in 7.8%(4/51) after TSA including hypopituitarism, diabetes insipidus, and visual loss. Non-existence of tumor in MRI and prolonged symptom duration(>3 years) were significant prognostic factors. Conclusion : TSA can be considered as initial treatment for Cushing's disease. In surgically failed cases, multiple treatment modality may improve the overall outcome and repeated TSA for recurrent cases seem to provide similar success.

  • PDF

Cavity-type Beam Position Monitors for Future Accelerators (차세대 가속기용 공동형 빔위치 측정기 개발)

  • Kim S.H.;Park Y.J.;Hwang W.H.;Huang J.Y.;Honda Y.;Inoue Y.
    • Journal of the Korean Vacuum Society
    • /
    • v.15 no.4
    • /
    • pp.331-337
    • /
    • 2006
  • Cavity-type beam position monitors were developed in collaboration with KEK to use for the future accelerators such as international linear collider (ILC) or x-ray free electron laser (XFEL) in PAL. BPM components such as BPM cavity, beam tubes, waveguides and feedthroughs were assembled by brazing at the same time to reduce mechanical errors during the fabrication. There are four screwed pins around outer rim of the cavity for the tuning of cavity frequency and x-y isolation. The resonance frequency of BPM is 6.422 GHz, the inner diameter of cavity is 53.822 mm, and the range of mechanical adjusting is $+ / - 250{\mu}m$. The x-y isolation was measured better than -40 dB after tuned. Test results of signal forms, x-y isolations, sensitivities are satisfied within requirements for the KEK ATF2 beam line.

Development of 3D Dynamic Numerical Simulation Method on a Soil-Pile System (지반-말뚝 시스템에 대한 3차원 동적 수치 모델링 기법 개발)

  • Kim, Seong-Hwan;Na, Seon-Hong;Han, Jin-Tae;Kim, Sung-Ryul;Sun, Chang-Guk;Kim, Myoung-Mo
    • Journal of the Korean Geotechnical Society
    • /
    • v.27 no.5
    • /
    • pp.85-92
    • /
    • 2011
  • The dynamic behavior of piles becomes very complex due to soil-pile dynamic interaction, soil non-linearity, resonance phenomena of soil-pile system and so on. Therefore, the proper numerical simulation of the pile behavior needs much effort and calculation time. In this research, a new modeling method, which can be applied to the conventional finite difference analysis program FLAC 3D, was developed to reduce the calculation time. The soil domain in this method is divided into a near-field region and a far-field region, which is not influenced by the soil-pile dynamic interaction. Then, the ground motion of the far-field is applied to the boundaries of the near-field instead of modeling the far-field region as finite meshes. In addition, the soil non-linearity behavior is modeled by using the hysteretic damping model, which determines the soil tangent modulus as a function of shear strain and the interface element was applied to simulate the separation and slip between the soil and pile. The proposed method reduced the calculation time by as much as one third compared with a usual modeling method and maintained the accuracy of the calculated results. The calculated results by the proposed method showed a good agreement with the prototype pile behavior, which was obtained by applying a similitude law to the 1-g shaking table test results.

A Model Test of IE and IR Method to Detect the Cavity Underneath the Concrete Structure (콘크리트 구조물 하부의 공동 탐지를 위한 충격반향(IE) 및 충격응답(IR) 기법의 모형 실험)

  • Noh, Myung-Gun;Oh, Seok-Hoon
    • Journal of the Korean earth science society
    • /
    • v.32 no.1
    • /
    • pp.1-11
    • /
    • 2011
  • The impact echo and impulse response methods were applied to the safety inspection of concrete structure, which has the rear cavity. The concrete structure model used in this study was divided into four sections, pure concrete, concrete+cavity, reinforced concrete with iron bar, and reinforced concrete+cavity, respectively. Previous study performed by authors have showed a possibility of success to use these method for detection of the rear cavity of concrete structure. Therefore, we tried to get more enhanced result with IE and IR methods through this study. Especially, IE and IR methods are relatively accurate to map the point of measurement, which makes it possible to interpret the depth of the concrete bed and effect by rear cavity with confidence. Followings were revealed from the results; the IE method shows some small peak zones probably indicating the rear cavity in the frequency lower than the resonance frequency and the changes of mobility and dynamic stiffness in the IR method indicate the weak zones. The proposed methods can be used to delineate the weak zones of the concrete structure.

A case of Transverse Myelitis due to Multidrug-Resistant Tuberculosis (다제내성 결핵에 의한 횡단척수염 1예)

  • Lee, Kwang Ha;Ra, Seung Won;Park, I-Nae;Choi, Hye Sook;Jung, Hoon;Chon, Gyu Rak;Shim, Tae Sun
    • Tuberculosis and Respiratory Diseases
    • /
    • v.60 no.3
    • /
    • pp.353-356
    • /
    • 2006
  • Acute transverse myelitis (TM) is a neurological syndrome caused by inflammation of the spinal cord. TM is rare but is frequently caused by viral or bacterial infections. TM caused by tuberculosis (TB) is extremely rare and there are no reports of TM caused by multidrug-resistant TB (MDR-TB). We report a case of acute TM due to MDR-TB in a 40-year-old man. The patient had been diagnosed with pulmonary TB and was started on the first-line anti-TB treatment. However, the chest radiographic findings were aggravated and neurological symptoms such as weakness in both lower extremities, sensory changes, and voiding difficulty were newly developed. The T2-weighted magnetic resonance image of the spine showed diffusely increased signal intensity in the spinal cord, particularly at the lower cervical and upper thoracic levels, without any definite evidence of myeloradicular compression, which is consistent with a diagnosis of TM. A drug susceptibility test revealed MDR and second-line anti-TB drugs were prescribed. The chest radiographic findings showed improvement after treatment, the mycobacterial culture converted to negative, the MRI findings improved, and there was partial improvement in the low extremity weakness. The patient has been prescribing second-line anti-TB medications for 14 months.

The Correlation of Levels of Serum Lipid, Homocysteine, and Folate with Volumes of Hippocampus, Amygdala, Corpus Callosum, and Thickness of Entorhinal Cortex in Patients with Amnestic Mild Cognitive Impairment or Dementia of Alzheimer's Type (기억성 경도인지장애 및 알츠하이머 치매 환자에서 해마, 편도체, 뇌들보, 내후각 피질과 혈중 지질, 호모시스테인, 엽산 농도와의 연관성)

  • Lee, Sang Jun;Kim, Tae Hyung;Huh, Lyang;Choi, Seung Eun;Lee, Bong Ju;Kim, Gyung Mee;Lee, Jung Goo;Kim, Hong Dae;Mun, Chi Woong;Kim, Young Hoon
    • Korean Journal of Biological Psychiatry
    • /
    • v.22 no.4
    • /
    • pp.223-232
    • /
    • 2015
  • Objectives In this study, the authors evaluated the correlation between levels of serum lipid, homocysteine, and folate with volumes of hippocampus, amygdala, corpus callosum, and in patients with amnestic mild cognitive impairment (aMCI) or Alzheimer's disease (AD) type. Methods The study recruited patients who visited the dementia clinic of Haeundae Paik Hospital in Korea between March 2010 and June 2014. Among those, patients who had taken the neurocognitive test, brain magnetic resonance imaing, tests for serum lipid, homocysteine, folate, and apolipoprotein E (APOE) genotyping and diagnosed with aMCI or AD were included for analysis. Bilateral hippocampus, entorhinal cortex, amygdala and corpus callosum were selected for region of interest (ROI). The cross-sectional relationships between serum lipid, homocysteine, folate and ROI were assessed by partial correlation analysis and multiple linear regression analysis. Results In patients with aMCI, old age (> 80) and APOE ${\varepsilon}4$ carrier were associated with AD [odds ration (OR) : 12.80 ; 95% confidence interval (CI) : 2.25-72.98 and OR : 4.48 ; 95% CI : 1.58-12.67, respectively]. In patients with aMCI or AD, volumes and thickness of ROI were inversely correlated with levels of serum lipid and homocysteine. In multiple linear regression analyses, higher total cholesterol level was related to lower left, right hippocampus volume and left amygdala volume ; higher low-density lipoprotein cholesterol was related to lower right entorhinal cortex thickness ; higher homocysteine level was related to lower corpus callosum volume. Conclusions Higher serum lipid and homocysteine levels are associated with decreased volume of hippocampus, amygdala, corpus callosum and entorhinal cortex thickness in patients with aMCI or AD. These findings suggest that serum lipid and homocysteine levels are associated with AD as a modifiable risk factor.