• Title/Summary/Keyword: Lessons-Learned

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Extravasation during Aneurysm Embolization without Neurologic Consequences. Lessons learned from Complications of Pseudoaneurysm Coiling. Report of 2 Cases

  • Hue, Yun-Hee;Yi, Hyeong-Joong;Kim, Young-Joon
    • Journal of Korean Neurosurgical Society
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    • v.44 no.3
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    • pp.178-181
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    • 2008
  • Although endovascular intervention is the first-line treatment of intracranial aneurysm, intraprocedural rupture or extravasation is still an endangering event. We describe two interesting cases of extravasation during embolotherapy for ruptured peripheral cerebral pseudoaneurysms. Two male patients were admitted after development of sudden headache with presentation of intracerebral and subarachnoid hemorrhage, respectively. Initial angiographic assessment failed to uncover any aneurysmal dilatation in both patients. Two weeks afterwards, catheter angiography revealed aneurysms each in the peripheral middle cerebral artery and anterior inferior cerebellar artery. Under a general anesthesia, endovascular embolization was attempted without systemic heparinization. In each case, sudden extravasation was noted around the aneurysm during manual injection of contrast after microcatheter navigation. Immediate computed tomographic scan showed a large amount of contrast collection within the brain, but they tolerated and made an unremarkable recovery thereafter. Intraprocedural extravasation is an endangering event and needs prompt management, however proximal plugging with coil deployment can be sufficient alternative, if one confronts with peripheral pseudoaneurysm. Peculiar angiographic features are deemed attributable to extremely fragile, porous vascular wall of the pseudoaneurysm. Accordingly, it should be noted that extreme caution being needed to handle such a friable vascular lesion.

BIM and Thermographic Sensing: Reflecting the As-is Building Condition in Energy Analysis

  • Ham, Youngjib;Golparvar-Fard, Mani
    • Journal of Construction Engineering and Project Management
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    • v.5 no.4
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    • pp.16-22
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    • 2015
  • This paper presents an automated computer vision-based system to update BIM data by leveraging multi-modal visual data collected from existing buildings under inspection. Currently, visual inspections are conducted for building envelopes or mechanical systems, and auditors analyze energy-related contextual information to examine if their performance is maintained as expected by the design. By translating 3D surface thermal profiles into energy performance metrics such as actual R-values at point-level and by mapping such properties to the associated BIM elements using XML Document Object Model (DOM), the proposed method shortens the energy performance modeling gap between the architectural information in the as-designed BIM and the as-is building condition, which improve the reliability of building energy analysis. Several case studies were conducted to experimentally evaluate their impact on BIM-based energy analysis to calculate energy load. The experimental results on existing buildings show that (1) the point-level thermography-based thermal resistance measurement can be automatically matched with the associated BIM elements; and (2) their corresponding thermal properties are automatically updated in gbXML schema. This paper provides practitioners with insight to uncover the fundamentals of how multi-modal visual data can be used to improve the accuracy of building energy modeling for retrofit analysis. Open research challenges and lessons learned from real-world case studies are discussed in detail.

The Effects of Technical Development, Market Expansion, Ecological Features, and Infirm Protective Policy on the Extinction of a Wild Life: A Case Study of Passenger Pigeons (기술발전, 시장팽창, 생태적 특성, 그리고 소극적 보호정책이 야생 동물의 멸종에 미친 영향: 미국 서부개척기의 여행비둘기를 사례로)

  • Song, Myung-Gyu
    • Journal of Environmental Impact Assessment
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    • v.19 no.5
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    • pp.483-495
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    • 2010
  • The passenger pigeon (Ectopistes migratorius) was a species of pigeon that was once the most common bird in North America. According to some ornithologists, the number of passenger pigeons is estimated as many as five to six billions at the time when the first Europeans arrived there. But this species became extinct in 1914. There were a multiplicity of causes in the extinction; first, the extension of telegraph lines and railroads into the Middle West of the USA beginning in 1850s, second, the loss of vast feeding, nesting, and roosting sites of the passenger pigeon due to the massive deforestation, third, the rapid population growth of the USA during nineteen century, fourth, the commercial exploitation of the species, and finally, the infirm and weak protective efforts. Some important lessons can be learned from the extinction of the passenger pigeon. First, it shows how much critical the public interest is for a successful conservational movement. Second, it illustrates the need for strong laws and practices in the protection of an endangered species from going extinct. Third, the fate of the passenger pigeon proves a very important principle in conservational biology. That is, for each species (bird or other animal) there is a minimum population to sustain the species. Ecologists generally believe that the extinction of the passenger pigeon was due to the loss of their numbers below the minimum owing to overexploitation.

Senolytics and Senostatics: A Two-Pronged Approach to Target Cellular Senescence for Delaying Aging and Age-Related Diseases

  • Kang, Chanhee
    • Molecules and Cells
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    • v.42 no.12
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    • pp.821-827
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    • 2019
  • Aging is the most important single risk factor for many chronic diseases such as cancer, metabolic syndrome, and neurodegenerative disorders. Targeting aging itself might, therefore, be a better strategy than targeting each chronic disease individually for enhancing human health. Although much should be achieved for completely understanding the biological basis of aging, cellular senescence is now believed to mainly contribute to organismal aging via two independent, yet not mutually exclusive mechanisms: on the one hand, senescence of stem cells leads to exhaustion of stem cells and thus decreases tissue regeneration. On the other hand, senescent cells secrete many proinflammatory cytokines, chemokines, growth factors, and proteases, collectively termed as the senescence-associated secretory phenotype (SASP), which causes chronic inflammation and tissue dysfunction. Much effort has been recently made to therapeutically target detrimental effects of cellular senescence including selectively eliminating senescent cells (senolytics) and modulating a proinflammatory senescent secretome (senostatics). Here, we discuss current progress and limitations in understanding molecular mechanisms of senolytics and senostatics and therapeutic strategies for applying them. Furthermore, we propose how these novel interventions for aging treatment could be improved, based on lessons learned from cancer treatment.

A Subjectivity Study on the Promotion of Korean Smart TV Industry through Q Methodology

  • Kim, Ki Youn;Cho, Dae Keun;Song, In Kuk
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.6
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    • pp.2171-2185
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    • 2014
  • From the perspectives of regulation and convergence, several debates on the industrial definition of smart TV service in the Korean broadcasting and communications market are currently in progress. The most heated controversy mainly depends on whether smart TV is controlled under broadcasting regulations or under communications regulations. This Korean- specific problem is summarized in regulation fairness or asymmetric regulations between smart TV and IPTV operators. Although both operators utilize very similar technology and share the same business model, the regulations for only smart TV operators are unfettered. This would be an intrinsic cause that prohibits fair competition in the new converging market. Currently we confront the matter of asymmetric regulations between smart TV and others including IPTV or ISP. The purpose of this study, thus, is to provide the strategic, regulatory guidance and theoretical definitions on smart TV service, as one of converging services, based on a qualitative approach through subjectivity methodology. The study identifies three issues net neutrality, regulation fairness and new media and new market and proposes desirable promotion plans regarding those issues. The study draws lessons learned through a Korean smart TV case and provides directions to strategic-policy studies for future emergent converging services.

The Effects of Korean and Family Life Education for Female Marriage Immigrant (결혼이민자를 위한 한국어와 가정생활교육효과)

  • Chae, Ock-Hi;Song, Sok-Hee
    • Journal of Family Resource Management and Policy Review
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    • v.13 no.2
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    • pp.107-127
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    • 2009
  • The purpose of this study was to explore how married female immigrants adjust to their lives in Korea. A total of 15 women from three different countries participated in the study. The major issues that these women faced included communication breakdowns with their husband and other family members, financial problems as well as problems with raising children in a different culture. The findings showed that such problems were usually rooted in a lack of Korean cultural knowledge and skills. Additionally, the inaccurate use of the language by married female immigrants who have lived in Korea for longer than six months was often fossilized. For instance, because they usually learned the language in a local dialect, it took them longer to distinguish the dialect from standard Korean. The results found that married female immigrants who received both Korean lessons and family life education instructions overcame their culture shock and adapted to Korean culture more easily than those who did not receive such instructions.

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A Case Study in a Rainfall induced Failure of Geosynthetics-Reinforced Segmental Retaining Wall (강우로 인한 보강토옹벽의 붕괴사례 연구)

  • Yoo, Chung-Sik;Jung, Hye-Young;Jung, Hyuk-Sang
    • Journal of the Korean Geosynthetics Society
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    • v.4 no.1
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    • pp.17-25
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    • 2005
  • This paper presents a case history of a geosynthetics-reinforced segmental retaining wall, which collapsed during a sever rainfall immediately after the completion of the wall construction. In an attempt to identify possible causes for the collapse, a comprehensive investigation was carried out including physical and strength tests on the backfill, stability analyses on the as-built design based on the current design approaches, and slope stability analyses with pore pressure consideration. The investigation revealed that the inappropriate as-built design and the bad-quality backfill were mainly responsible for the collapse. This paper describes the site condition including wall design, details of the results of investigation and finally, lessons learned. Practical significance of the findings from this study is also discussed.

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An Experimental Study of Fuselage Drag and Stability Characteristics of a Helicopter Configuration (회전익 항공기 형상의 기체공력 특성에 관한 실험적 연구)

  • Oh, Se-Yoon;Park, Keum-Yong;Lee, Jong-Geon;Ahn, Seung-Ki
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.33 no.9
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    • pp.9-15
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    • 2005
  • This paper describes the test carried out on an experimental study of fuselage drag and stability characteristics of a helicopter configuration and the test techniques developed for the testing and the lessons learned in the Agency for Defense Development Low Speed Wind Tunnel(ADD-LSWT). The main objective of this test is to determine the drag and stability characteristics of helicopter configurations according to the various configuration changes. The fuselage model with a highly modular structure is a representation of 1:8 scale of the external contour of the conceptual design helicopter configuration with rotating main rotor hub including blade stubs capable of rotating up to 500 rpm. The test results are compared with the available similar data and fair to good agreement is obtained.

Study on the lateral stability improvement and compliance verification (소형비행기 가로안정성 향상 및 적합성검증 방안 연구)

  • Choi, Joo-Won;Kim, Chan-Jo;Jung, Hoon-Hwa;Kim, Jin-Su
    • Journal of Aerospace System Engineering
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    • v.7 no.2
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    • pp.23-28
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    • 2013
  • This is a research on the method of how to improve lateral stability for the small general aviation airplane to meet the FAR part 23 requirements. This research is based on the experience of certification flight tests of KC-100 airplane for Korea first type certification. KAS/FAR Part 23.177 is the static lateral and directional stability requirement. And, 23.177(b) requires to show the tendency to raise the low wing in steady heading side slip maneuver. However, it is very difficult for the low wing to be raised at the low speed during the steady heading side slip maneuver. So, the requirement allows not be negative at the $1.2V_{S1}$ speed and takeoff configuration. (static stability requirement requires low wing picked up at any speed except $1.2V_{S1}$ speed and takeoff configuration) In this paper, the static lateral stability requirements and the lessons & learned of KC-100 airplane certification flight test results are shown.

REVIEW OF 15 YEARS OF HIGH-DENSITY LOW-ENRICHED UMo DISPERSION FUEL DEVELOPMENT FOR RESEARCH REACTORS IN EUROPE

  • Van Den Berghe, S.;Lemoine, P.
    • Nuclear Engineering and Technology
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    • v.46 no.2
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    • pp.125-146
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    • 2014
  • This review aims to provide a synthesis of the knowledge generated and the lessons learned in roughly 15 years of UMo dispersion fuel R&D in Europe through a series of irradiation experiments. A lot of irradiations were also performed outside of Europe, particularly in the USA, Russia, Canada, Korea and Argentina. In addition, a large number of out-of-pile investigations were done throughout the world, providing support to the understanding of the phenomena governing the UMo behaviour in pile. However, the focus of this article will be on the irradiations and Post-Irradiation Examination (PIE) results obtained in European experiments. The introduction of the article provides a historic overview of the evolution and progress in the high density UMo dispersion fuel development. The ensuing sections then provide further details on the various phases of the development, from the UMo dispersion in a pure Al matrix through the addition of Si to the matrix to address the interaction layer formation and finally to the more advanced solutions to the excessive swelling encountered in various experiments. This review was based only on published results or results that are currently in the process of being published.