태양 중분산 분광 망원경 개발

조경석,조경석,문용재,장비호,김수진,김연한,Park, Y.D.,Cho, K.S.,Moon, Y.J.,Jang, B.H.,Kim, S.J.,Kim, Y.H. 한국천문학회 2003 天文學論叢 Vol.18 No.1

In 2002, a new solar spectroscopic system with the Coelostat type has been installed at Korea Astronomical Observatory. It was designed to observe solar spectra in the range from 3000 to 8000${\AA}$ with the spectral resolution of 1${\AA}$/mm. The system is composed of a 40cm diameter Coelostat with 9m focal length, spectroscopic system with 600groove/mm grating, and a IK ${\times}$ IK CCD detector. By developing observational softwares for this system, we have successfully observed solar Ha spectra. In this paper, we development of telescope control and observational softwares.

혈관성 시상부 병변시 다발성 유발전위 검사의 의의

조경석,라형균,안명수,최창락,송진언 대한신경외과학회 1985 Journal of Korean neurosurgical society Vol.14 No.1

We reviewed the cases of 9 patients with vascular lesions in thalamus, 5 hemorrhage and 4 infarctions that were confirmed clinical and CT findings. Generally CT scan and clinical datas proved to be helpful to the diagnosis and prognosis to thalamic lesion. However, these findings are not exactly correlated to prognosis of patients. We can gain more informative factors to our patients for Multimodal evoked potential examination (MEP) to analysis. Especially in our cases, MEP findings proved to be the most effective results in the determinations of the prognosis. We review the literature and discuss the treatment and discuss the treatment and prognosis in thalamic lesion. Emphasis is placed on the current and optimal method of the evaluation of prognosis in thalamic lesions using MEP combined with the finding of CT scan and clinical status.

수력발전소 수명연장 및 현대화 계획

조경석,권창섭 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.5

Korean Space Weather Activities

조경석,박영득,안병호 한국천문학회 2013 天文學會報 Vol.38 No.1

급성 뇌허혈증에 있어 만니톨의 효과에 대한 실험적 연구

조경석,홍용길,백민우,김달수,강준기,최창락 대한신경외과학회 1994 Journal of Korean neurosurgical society Vol.23 No.8

The development of postischemic irreversible brain damage depends upon the length of ischemia and its severity during arterial occlusion, although release of the occlusion always leads to restoration of normal or above n o d cerebral blood flow. This experiment was planned to determine the effects of mannitol on cerebral ischemia on subsequential izgional cerebral blood flow(rCBF) and somatosensory evoked potential(SEP) following reperfusion after ischemia and also define the proper time of vascular occlusion without irreversible brain damage. Cerebral ischemia was induced in cat by transorbital occlusion of the left MCA with a Sugita clip for period of 30 minutes and the ischemic brain was reperfused for 180 minutes by removing the clip. Foty adult cats, weighing 25 to 4.0㎏ were divided into 5 groups : control(Gmup Ⅰ, n=8), permanent MCA occlusion(Group Ⅱ, n= 8), permanent MCA occlusion with mannitol infusion (Group Ⅲ, n=8), permanent MCA occlusion with mannitol infUsion(Group Ⅲ, n=8), 30 minutes MCA clipping followed by reperfusion(Gmup Ⅳ, n= 8) and 30 minutes MCA clipping with mannitol infusion followed by reperfusion groups((group Ⅴ, n=8) respedvely. The rCBF and SEP measurents were carried out in each animal immediately, after MCA occlusion, at 30 minutes, 60 minutes, 90 minutes, 120 minutes, 150 minutes and 180 minues followed by reperfusion. The rCBF was measured by the hydrogen clearance technique. Mando1 was given in bolus of l a g body weight as a 25% solution delivered via the femoral vein The results were as follows: 1) Gradual elevation of intracranial pressure(1CP) and systolic blood pressure were observed after MCA occlusion. Treatment with mannitol in MCA occlusion animals(Group Ⅲ & Ⅴ) decreased ICP immediately a k r idusion of mannitol. 2) Normal control rCBF(ml/100g/min) were 51.94±5.05 in the left temporal(LT) and 50.80± 4.87 in the left perietal lobes(LP). 3) The MCA occlusion resulted in a reduction of the blood flows to 72% of the normal control ones(LT : 14.29± 4.81ml/100g/min) at the left temporal area immediately after occlusion and also a reduction of flows to 80.4% of the normal control ones(LT : 1024± 3.69ml/100g/min) at 180 minutes after occlusion in Group Ⅱ. 4) In the mannitol-treated group(group Ⅳ), reperfwd animals, with removal of the clip on MCA had an improved postischemic recovely of blood flow and ipsilateral cerebral blood flows were restored to 42.5% of the normal control ones(LP : 212±4.13ml/100g/min) at 180 minutes after occlusion in Lt parietal CBF. 5 ) In the reperfusion group(group Ⅳ), reperfused animals, with removal of the clip on MCA had an increase in rCBF to the level of 833% of the control value(LT : 45.78± 6.80ml/100g/min) at 180 minutes after reperfusion and also reperfused animals, with treated mannitol had further increase the blood flow up to the level of 92s % of the control value(LT : 49.04± 43.6 ml/100g/min) at 180 minutes after repexfwion. 6) After the MCA occlusion, the SEP was present but markedly altered in shape and particularly the early components of the SEP were suppressed in the ipsilateral occlusion hemisphere. 7) In the mannitol-treated reperfusion group(Group Ⅴ) the amplitude of the SEP was restored to 80% of control value. The SEP was significantly suppressed if the rCBF fell below 10- 14ml/100g/min. These results suggest that provided CBF can be restored to above the 40% threshold well within 30 minutes, prevention of ischemic brain damage can be expected and also the mannitol may of benefit in prolongation of the time threshold for the formation of the cerebral ischemia after vessel occlusion.

A HIGH FREQUENCY TYPE II SOLAR RADIO BURST ASSOCIATED WITH THE 2011 FEBRUARY 13 CORONAL MASS EJECTION

조경석,권륜영,김록순,Cho, Kyungsuk,Gopalswamy, Nat,Kwon, Ryunyoung,Kim, Roksoon,Yashiro, Seiji 한국천문학회 2012 天文學會報 Vol.37 No.2

We examine the relationship between a type II radio burst that started from an unusually high frequency of 425 MHz (fundamental component) and an associated white-light coronal mass ejection on 2011 February 13. The radio burst had a drift rate of 2.5 MHz/sec, indicating a relatively high shock speed. From SDO AIA observations we find that a loop-like erupting front sweeps across high density coronal loops near the start time of the burst (17:34:15 UT). We find fragmented structures of the type II burst, which indicates the signature of the shock propagating through the multiple loops. The deduced distance of shock formation (0.06 Rs) from flare center and speed of the shock (1100 km $s^{-1}$) using the measured density from AIA/SDO observations are comparable to the height (0.05 Rs, from the solar surface) and speed (700 km $s^{-1}$) of the CME leading edge observed by STEREO/EUVI. We conclude that the type II burst could be onset even in the low corona (41 Mm or 0.06 Rs, above the solar surface) if a fast CME shock passes through the high density loops.

두개강내 추골 동맥의 박리성 동맥류 : Case Report

조경석,김달수,하영수,강준기,송진언 대한신경외과학회 1985 Journal of Korean neurosurgical society Vol.14 No.1

A case of dissecting aneurysm of the intracranial vertebral artery in 46-year-old man is reported. Dissecting aneurysm of the vertebral artery associated with SAH is very rare. The characteristic angiographic findings of dissecting aneurysm were: 1) retention of contrast medium in the aneurysm ; 2) the presence of double lumina ; 3) "String " or "Pearl - string " sign. The therapeutic occlusion of the intracranial vertebral artery was performed successfully.

태양광구의 벡터 자기장 구조

조경석,김갑성,Jo, Gyeong-Seok,Kim, Gap-Seong 한국천문학회 1995 天文學論叢 Vol.10 No.1

We have intensively examined the structure of photospheric magnetic fields obtained from the calculation of the polarized radiation transfer for the model atmosphere. To determine more reliable magnetic field in the photospheric region composed of umbra, penumbra and quite area, we have calculated the polarized radiative transfer for a magnetically sensitive spectral line, FeI $6302.5{\AA}$, using our composite model representing three kinds of the atmospheric area distinguished by the pixel value of the Stokes I image over the region. Polarization data of the full Stokes parameters, used in this paper had been obtained from the vector magnetograph on Solar Flare Telescope of National Astronomical Observatory at Mitaka(MTK) in Japan. According to our investigation on the active region in the photosphere, it has been found that the large current density(${\geq}8{\times}10^2A/km^2$) and shear angle(${\geq}85^{\circ}$) should be distributed along the magnetic neutral line. To be compared with the results of MTK, our results in transverse magnetic field strength and direction are similar with those of MTK, however our longitudinal field strength at the center of the spot is somewhat(${\sim}1000$ Gauss) larger than MTK.

정상압 뇌수종의 수술선택에 대한 연구

조경석,백민우,김문찬,강준기,송진언 대한신경외과학회 1987 Journal of Korean neurosurgical society Vol.16 No.1

Normal pressure hydrocephalus (NPH) is defined as a combination of dementia, gait disturbance and/or urinary incontinence, hydrocephalus on C - T scan, with a normal intracranial pressure. The clinical effect of CSF shunting in patients with this syndrome is sometimes striking but generally only 50-60% of the shunted patients benefit from the treatment. So many pre-operative investigations are performed including clinical examination, computed tomography, R - I cistemography, T 1/2 calculated from ventricular volume pressure curve and lumbar drainage. Among the pre - operative investigations, the effect of preoperative lumbar drainage was the most reliable indicator of NPH. The possible mechanisms of improved case are proposed. The differential diagnosis of primary brain atrophy and NPH can be made by the effect of pre-operative lumbar drainage.

만성신경압박의 병리조직학적 고찰

조경석,이재수,백민우,하영수,강준기,송진언,최창락 대한신경외과학회 1990 Journal of Korean neurosurgical society Vol.19 No.5

Recently nerve entrapments or nerve root compressions are common clinical symdromes. However, a clear understanding of both pathophysiological and morphological changes is lacking and it may not be completely established in the experimental model for chronic nerve compression, compared with a surprising review of peripheral nerve exposed to various acute damage. Adult Sprague-Dawley rats weighing 250 to 300 g were used as the experimental model to elucidate histopathological changes in chronic nerve compression, which were produced by banding the sciatic nerve(normally 1.2㎜ in diameter) with the length of 1㎝ silastic tubings with inner diameter, 0.6㎜ (Group Ⅰ), 0.9㎜ (Group Ⅱ) and 1.5㎜ (Group Ⅲ) in each. Specimens were obtained for light and electron microscopic studies postoperatively at 1 and 3 months following by nerve conduction study. Grossly in group Ⅰ, the sciatic nerve was compressed to approximately 50% of its normal in cuff area and in thin strand on distal part at 1 month and more progressed at 3 months. The sciatic nerve of group Ⅱ demonstrated 75% of control and distal part in 50% compression at 1 month, but the nerve seemed not to be affected by tubing. Light microscopic findings revealed Wallerian degeneration and diminished large myelinated fiber particularly in the periphery of nerves with 34% of transverse neural percentage in group Ⅰ at postoperative 1 month. Above findings were progressed to epineurial scarring and fibrosis at 3 months. There were marked diminution and deformity in large myelinated fiber in group Ⅱ, but it was not more severe than the ones of group Ⅰ. Electron microscopic findings in this group revealed the appearance of small regenerating unit clusters and thinly myelinated fibers. In group Ⅲ, histological findings were not much different from that of normal nerve. Nerve conduction study revealed the decrease in conduction velocity to mean 10 M/sec in group Ⅰ at 1 month and no electrical conduction at 3 months. In group Ⅱ, diminution of conduction velocity in 73% of normal range at I1month was noted, and 82% at 3 months. These findings explain correspondingly the histopathological changes in part of chronic nerve entrapment syndromes and appeal the need of further investigation in this experimental model.