• 한국재난정보학회:학술대회논문집
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• 한국재난정보학회 2022년 정기학술대회 논문집
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• pp.407-411
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• 2022

공항 시설에서 통틀어 보안이 가장 취약한 곳은 Landside이다. 항공기 테러가 빈번하던 시절에는 X-ray를 비롯한 검색기술의 수준이 높지 않았던 탓에 Hijacking이나 폭발물에 의한 피해가 많았었다. 물론 기술이 발전한 현대에 와서도 Hijacking이나 항공기 폭파 같은 테러가 발생하고 있지만 9.11테러 이전보다는 훨씬 감소한 상황이다. 최근에는 보안수준이 높은 Airside 보다 상대적으로 보안이 취약한 Landside에 대한 보안 강화가 필요하다. 그 이유는 테러의 유형이 협상의 여지가 없는 최대피해와 최대공포를 주는 방식으로 변화하고 있기 때문이다. 따라서 상대적으로 부담이 덜하고 유동인구가 많은 Landside가 Soft Target이 되었다. 이런 상황에서 대한민국 공항이 어떻게 대응해야 하는지 관련된 법을 중심으로 본 연구를 진행해 보고자 한다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권1호
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• pp.9-15
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• 2010

Aim of the study: As an injectable scaffold, MPEG-PCL diblock copolymer was applied in bone tissue engineering. In vivo bone formation was evaluated by soft X-ray, histology based on the rat calvarial critical size defect model. Materials and Methods: New bone formation was evaluated with MPEG-PCL diblock copolymer in rat calvarial critical size bone defect. No graft was served as control. 4, 8 weeks after implantation, gross evidence of bone regeneration was evaluated by histology and soft X-ray analysis. Results: The improved and effective bone regeneration was achieved with the BMP-2 and osteoblasts loaded MPEG-PCL diblock copolymer. Conclusion: It was confirmed that MPEG-PCL temperature sensitive hydrogels was useful as an injectable scaffold in bone regeneration.

• 한국어병학회지
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• 제20권2호
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• pp.129-137
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• 2007

인공 종묘 생산한 황복 (Takifugu obscurus)자어의 사육 중에 발생한 척추 변형의 원인을 조사하기 위하여 변형어를 병리조직학적으로 조사하였다. 척추 변형은 부화 후 80일령의 황복으로 변형의 발생율은 전체 사육 미수의 약 90%였다. 변형어를 soft-X ray로 촬영한 결과 부레의 팽창은 정상적이었으며, 병리조직학적으로는 변형이 발생한 척추 주변의 근섬유 다발이 소형화되면서 모양도 불규칙하게 변하였다. 그러나 새변 연골은 뒤틀림이나 증생 등은 관찰되지 않았다. 척추 변형이 발생한 종묘 생산장에서는 일반적인 사육 방식보다 1-2일 정도 사육수를 빨리 순환시키면서 급이하고 있었는데, 그 후 황복이 무리를 형성하고 나서, 급이하면서 사육수를 환수한 결과 변형의 발생은 없었다. 병어의 조직학적 변화를 사육방식과 더불어 고찰하였을 때, 유영 능력이 불완전한 황복에 급이하면서 사육수를 환수시킴으로써 황복이 먹이를 섭취하기 위하여 수류에 저항하면서 유영한 것이 척추 변형의 원인으로 작용하였을 것으로 생각한다.

• 한국수산과학회지
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• 제48권4호
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• pp.474-482
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• 2015

This study aims to investigate the patterns and incidence rates of morphological deformities during artificial fingerling production of blackhead seabream (BSB, Acanthopagrus schlegeli) juveniles by visual and soft X-ray observations of BSB juveniles (n=881) collected from four industrial hatcheries. Using both methods, we observed seven types of external deformity ($11.2{\pm}4.4%$) and eight types of skeletal deformity ($53.4{\pm}5.1%$). Lordosis occurred in all hatcheries with the highest frequency and the mean frequency was $13.1{\pm}4.4%$ (24.5% in total abnormal) by soft X-ray. Although they had a similar standard length (SL), juveniles with lordosis had a significantly lower condition factor and body weight than normally developed juveniles (P<0.05); normal distribution curves of histogram of body proportions, i.e., body height (BH)/head length (HL) and trunk (=SL-HL)/BH, indicated differences between normally developed juveniles and those with lordosis. In addition, 59% of juveniles with lordosis had vertebral curvature of less than $20^{\circ}$, generally at the $17^{th}$ vertebrae. It is expected that the above results will be used as basic data necessary for determining the cause of lordosis and for developing techniques to prevent this symptom in the fingering production industry of BSB juveniles.

• 천문학회보
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• 제35권1호
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• pp.27.2-27.2
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• 2010

We have studied the formation of coronal holes (CHs) associated with halo CMEs. For this study, we used multi-wavelength data from Yohkoh Soft X-ray Telescope (SXT), GOES Soft X-ray Imager (SXI), SOHO EIT 195 ${\AA}$, SOHO MDI magnetogram, MLSO He I 10830 ${\AA}$, and BBSO H-alpha. The CHs are characterized by open magentic field regions with low emission, density, and temperature and their open fields drive high speed solar winds which cause geomagnetic storms. So far, the formation and the evolution of CHs are not well understood. The formation of the dark region associated with the eruption of a CME is well known as "coronal dimming" which may be caused by the mass depletion near the CME footpoint. It is different from a typical CH since it persists for only one or two days. In this study, we present three cases that show the formation of coronal holes which are associated with three halo CMEs: 1) 2000 Jul 14, 2) 2003 Oct 28, 3) 2005 May 13. In the first case, hot plasma was ejected during a weak eruption and then filled out the pre-existing CH. After the halo CME occurred, the hot plasma region becomes a CH again. In the second and the third cases, we found newly formed CHs just after their associated CMEs. All three coronal holes are associated with strong flares and persist over 3 days until they disappeared by the solar rotation. Examining the MDI magnetograms, we found that the magnetic polarity of each CH region has one polarity. Based on these results, we suggest that the coronal holes can be formed by the CMEs and they should be distinguished from the coronal dimming.

• Journal of the Korean Wood Science and Technology
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• 제28권1호
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• pp.1-17
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• 2000

황철나무와 양황철나무는 전형적인 다습심재(wetwood)로써, 심재 전체가 변재보다 높은 함수유를 나타냈다. 황철나무와 양황철나무의 목부중에 존재하는 결정은 주로 심재중에서도 일부연룬을 따라 또는 착색얼룩을 따라 또는 국소에 집중하여, 수에 가까울수록 많았다. 또한 1연륜 내에서는 만재보다 조재에 많은 경향이 있었다. 심재에서의 결정은 전 종류의 세포에 존재하였으나, 대부분의 결정은 도관과 섬유상가도관에 존재하였다. 수피중에 있는 결정은 내수피에서 외수피까지 비교적 산재하여 존재했다. 양황철나무에서는 잎옹이의 출현빈도가 높았으나 황철나무에서는 그 출현 빈도가 낮았다.

• 대한치과교정학회지
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• 제20권3호
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• pp.427-446
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• 1990

The objective of this study was to understand the major changes of craniofacial dimensions and spatial growth pattern during the late embryonic and fetal period of human fetures. This study was performed with the selective materials of normal fetuses received from the Registry of Congenital Malformation of Seoul National University Hospital. The specimens consisted of nineteen embryos and sixty-six fetuses. The photomicrographs from mid-segittal sections of embryos were used for angular measurement, and the lateral cephalograms taken with soft X-ray were also measured in liners and angular aspects. All of the anatomical landmarks for the tracing of the photomicrographs and cephalograms were referred to the previous reports on literature. The sequential changes of prenatal craniofacial dimensions and agles were analysed statistically and discussed on the focus about the developmental growth directions of human ore-facial structure arised from heterogeneous origins. The results are as follows, 1) Cranial base angle was almost formed at about 6 weeks old embryos with the average angle of $127.4{\pm}6.33^{\circ}$ (n=3) and it was almost constant onwards. 2) The linear increase rates of anterior cranial base length and anterior facial height exceeded those of the posterior cranial base length and posterior facial height, and the maxilla grows more rapidly on the horizontal dimension than the vertical dmension during the fetal period. 3) The angular relationship between the anterior cranial base and palatal plane decreasedslightly during the fetal period, disclosing $11^{\circ}$ at 12th week gestation and $5^{\circ}$ at 41th weeks gestation. 4) Genial angle was maintained almost constantly at about $130^{\circ}$ during the fetal period from 12 weeks to 41 weeks of gestation.

• Imaging Science in Dentistry
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• 제37권2호
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• pp.69-77
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• 2007

Purpose: To evaluate the accuracy of the imaging reformation of cone beam computed tomography for the assessment of bone defect healing in rat model. Materials and Methods: Sprague-Dawley strain rats weighing about 350 gms were selected. Then critical size bone defects were done at parietal bone with implantation of collagen sponge. The rats were divided into seven groups of 3 days, 1 week, 2 weeks, 3 weeks, 4 weeks, 6 weeks, and 8 weeks. The healing of surgical defect was assessed by multi planar reconstruction (MPR) images and three-dimensional (3-D) images of cone beam computed tomography, compared with soft X-ray radiograph and histopathologic examination. Results: MPR images and 3-D images showed similar reformation of the healing amount at 3 days, 1 week, 2 weeks, and 8 weeks, however, lower reformation at 3 weeks, 4 weeks, and 6 weeks. According to imaging-based methodologies, MPR image revealed similar reformation of the healing amount than 3-D images compare with soft X-ray image. Among the four threshold values for 3-D images, 400-500 HU revealed similar reformation of the healing amount. Histopathologic examination confirmed the newly formed trabeculation correspond with imaging-based methologies. Conclusion: MPR images revealed higher accuracy of the imaging reformation of cone beam computed tomography and cone beam computed tomography is a clinically useful diagnostic tool for the assessment of bone defect healing.

• 한국환경생태학회지
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• 제7권2호
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• pp.192-206
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• 1994

국립공원에서 자연보존의 일환으로 기초자료를 축적하고자 1993년 5월부터 11월까지 덕유산국립공원 일대의 9개 지소에서 담수어류상을 조사한 결과 한국고유종 및 아종인 칼납자루, 긴몰개, 돌마자, 금강모치, 참종개, 미유기, 동사리를 포함한 5개과 17종의 담수어류를 확인하였다. 금강수계에서는 16종이, 낙동강수계에서는 8종이 분포하였으며 공통적으로 분포하는 어종은 긴몰개, 돌마자, 돌고기, 버들치, 갈겨니, 미꾸리 및 동사리로서 7종이었고 우세종은 버들치, 갈겨니 그리고 동사리였다. 한편 한국산 담수어의 형태에 관한 기초자료 축적의 일환으로 이지역에서 채집된 담수어 17종의 척추골수를 soft X-ray를 활용하여 그 분석결과를 보고함과 아울러 수계의 환경훼손에 따른 어류의 비정상적 골격형질 발현양상 파악결과의 활용가능성을 검토하였다.

• The Journal of Advanced Prosthodontics
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• 제7권2호
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• pp.151-159
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• 2015

PURPOSE. To describe and characterize the surface topography and cleanliness of CAD/CAM manufactured zirconia abutments after steaming and ultrasonic cleaning. MATERIALS AND METHODS. A total of 12 ceramic CAD/CAM implant abutments of various manufacturers were produced and randomly divided into two groups of six samples each (control and test group). Four two-piece hybrid abutments and two one-piece abutments made of zirconium-dioxide were assessed per each group. In the control group, cleaning by steam was performed. The test group underwent an ultrasonic cleaning procedure with acetone, ethyl alcohol and antibacterial solution. Groups were subjected to scanning electron microscope (SEM) analysis and Energy-dispersive X-ray spectroscopy (EDX) to verify and characterize contaminant chemical characterization non- quantitatively. RESULTS. All zirconia CAD/CAM abutments in the present study displayed production-induced wear particles, debris as well as organic and inorganic contaminants. The abutments of the test group showed reduction of surface contamination after undergoing an ultrasonic cleaning procedure. However, an absolute removal of pollutants could not be achieved. CONCLUSION. The presence of debris on the transmucosal surface of CAD/CAM zirconia abutments of various manufacturers was confirmed. Within the limits of the study design, the results suggest that a defined ultrasonic cleaning process can be advantageously employed to reduce such debris, thus, supposedly enhancing soft tissue healing. Although the adverse long-term influence of abutment contamination on the biological stability of peri-implant tissues has been evidenced, a standardized and validated polishing and cleaning protocol still has to be implemented.