• The Korean Journal of Quaternary Research
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• v.13 no.1
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• pp.25-33
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• 1999

The relationships between climate (monthly precipitation and temperatures) and tree-ring growth of Korean fir (Abies koreana) growing at subalpine (1,600∼l,700m) zone on the south slope, Joong-Bong and the north slope, Changgun-Bong in the Cheonwang-bong area in Chiri mountains in the southern Korea were analyzed. Two cores from each of 10∼12 trees were extracted. The relationship between tree-ring(standardized) chronologies and climate was analyzed by the response-function method. Climate variables could explain 45.9∼53.8% of total variance in the chronologies. The precipitation response function of Korean fir were similar at both sites in overall ; positive for March∼May and August, and negative for February and July. The south-slope fir of Joong-Bong possessed higher negative temperature response function for February and August than north-slope one. The positive response function for April temperature was significant for both sites. In contrary to other subalpine species (e.g., Pinus koraiensis and Taxus cuspidata) in South Korea, whose growths are positively correlated with temperature in most seasons, the growths of Korean fir trees in Mt. Chiri appeared to be mainly limited by the moisture regime of spring prior to the cambial growth and early growing season.

• Journal of Satellite, Information and Communications
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• v.8 no.4
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• pp.150-158
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• 2013

In Korea, the official monitoring of the atmospheric re-entry of satellites or space debris was initiated by the first operation of a re-entry situation analysis team for the 'Cosmos 1402' of the Soviet Union, which main body re-entered on January 23, 1983 and radio active core re-entered on February 7, 1983. After this incident, a task force team consisting Korea Astronomy and Space Science Institute (KASI), Korea Aerospace Research Institute (KARI) and other related institutes operated a situation monitoring group under the supervision of the Ministry of Science and technology (MOST) for the controlled re-entry of the Russian 'Mir' space station in 2001. The re-entry of the upper atmospheric weather satellite 'UARS' of United States had been monitored and analyzed by KASI on September 24, 2011. As the re-entry of the space object has been frequently occurred, the government officials and the experts from MEST (Ministry of Education, Science and Technology), KASI, KARI had an urgent official meeting to establish a satellite re-entry monitoring room in KASI and to give an operational authority to KASI in September 14, 2011. Under this decision, the satellite re-entry monitoring room in KASI has successfully executed the monitoring, data analyzing, official reporting, media contacting, and public announcing for the German satellite 'Roentgen' in October 2011, Russian space explorer 'Phobos-Grunt' in January 2012, Russian satellite 'Cosmos 1484' in January 2013, and European geodetic satellite 'GOCE' in November 2013 with the support from the Korean Air Force and KARI.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.879-882
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• 2008

The market of Korea of post-tension system for building is growing up since 2000 and many engineers and construction companies show interest in it. This paper introduces the structure system and construction of post-tension tall buildings including recent trend in the industry of post-tension system for buildings in Korea and the point to be considered when design post-tensioned tall building. Park Polis is composed of two towers of 39 stories with a level to the top of the roof +144m and is currently under construction at Ulsan in Korea. This building designed as the unbonded post-tension floor system and will be the tallest and first high-rise post-tensioned building in Korea. The structural system is composed of the flat slabs, perimeter columns and core walls. At first, this building had designed as regular RC flat slab with perimeter beams. However, floor structure system was reconsidered because the construction company wants to improve efficiency of construction. As a result, the floor system of PARK POLIS re-designed as PT flat slab.

• Magazine of the Korea Concrete Institute
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• v.20 no.6
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• pp.28-35
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• 2008

The Burj Dubai Project will be the tallest structure ever built by man; when completed the tower will be more than 700 meter tall and more than 160 floors. While the early integration of aerodynamic shaping and wind engineering considerations played a major role in the architectural massing and design of this multi-use/residential tower, where mitigating and taming the dynamic wind effects was one of the most important design criteria, the material selection for the structural systems of the tower was also a major consideration and required detailed evaluation of the material technologies and skilled labor available in the market at the time Concrete was selected for its strength, stiffness, damping, redundancy, moldability, free fireproofing, speed of construction, and cost effectiveness. In addition, the design challenges of using concrete for the design of the structural system components will be addressed. The focus on this paper will also be on the early planning of the concrete works of the Burj Dubai Project.

• Journal of the Korea Institute of Building Construction
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• v.18 no.6
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• pp.517-525
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• 2018

The construction of super tall building which structure is RC and must be certainly considered on column shortening estimation and construction reflected concrete creep has been increased. Regarding the Fck 60~80MPa grade high strength concrete applied in the domestic super tall building project, the mechanical properties and creep deflection according to curing conditions(Drying creep/Basic creep) were reviewed in this research. Results of compressive strength and elastic modulus under sealed curing condition were 5% higher than unsealed condition and difference of results according to the curing condition was increased over time. Autogenous and drying shrinkage tendency showed adversely in the case of high strength concrete. Additionally, creep modulus under unseal curing condition was evaluated 2~3 times higher than sealed condition. Modified model of ACI-209 based on test result was applied to estimate long period shortening of vertical members(such as Core Wall/Mega Column) exactly, it is designed to modify and suggest the optimal creep model based on various data accumulated during construction, in the future.

• Journal of the Korea Society of Computer and Information
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• v.26 no.6
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• pp.73-80
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• 2021

In this paper, we propose a packet processing method capable of handling large-capacity traffic over 20Gbps using multi-core and huge page memory approaches. As ICT technology advances, the global average monthly traffic is expected to reach 396 exabytes by 2022. With the increase in network traffic, cyber threats are also increasing, increasing the importance of traffic analysis. Traffic analyzed as an existing high-cost foreign product simply stores statistical data and visually shows it. Network administrators introduce and analyze many traffic analysis systems to analyze traffic in various sections, but they cannot check the aggregated traffic of the entire network. In addition, since most of the existing equipment is of the 10Gbps class, it cannot handle the increasing traffic every year at a fast speed. In this paper, as a method of processing large-capacity traffic over 20Gbps, the process of processing raw packets without copying from single-core and basic SMA memory approaches to high-performance packet reception, packet detection, and statistics using multi-core and NUMA memory approaches suggest When using the proposed method, it was confirmed that more than 50% of the traffic was processed compared to the existing equipment.

• Information Systems Review
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• v.22 no.1
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• pp.147-165
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• 2020

The sharing economy service is now spreading in various fields such as accommodation, cars and bicycles. In particular, bicycle-sharing service have become very popular around the world, and since September 2015, Seoul has been providing a bicycle-sharing service called 'Ttareungi'. However, the number of bicycles is unbalanced among rental stations continuously according to the user's bicycle use. In order to solve these problems, we employed social network analysis using Ttareungi data in Seoul, Korea. We analyzed degree centrality, closeness centrality, betweenness centrality and k-core. As a result, the degree centrality was found to be closely linked with bus or subway transfer center. Closeness centrality was found to be in an unbalanced departure and arrival frequency or poor public transport proximity. Betweenness centrality means where the frequency of departure and arrival occurs frequently. Finally, the k-core analysis showed that Mapo-gu was the most important group by time zone. Therefore, the results of this study may contribute to the planning of relocation and additional installation of bike rental station in Seoul.

• Journal of the Korean Arthroscopy Society
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• v.14 no.1
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• pp.1-6
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• 2010

This study was undertaken to document the clinical results and technical aspects of arthroscopic repair including popliteus tendon as a post for the treatment of complex lateral meniscus in young people indicated as total meniscectomy. From June 2004 to May 2006, we prospectively studied arthroscopic repairs on 32 young people knees with symptomatic complex lateral meniscus that was treated by all inside repair technique using Popliteus tendon as a post. Clinical results were evaluated using Lysholm knee scores preoperatively and at final follow-up. 2nd look arthroscopy or MRI was taken at final follow-up. 80% of patients carried out MRI or 2nd look arthroscopy under permission. Most patients who follow up were able to return to their previous life activities with little or no limitation, and no reoperation was required after an average follow-up of 42.8 months. Mean Lysholm knee scores improved from 65.4 (range, 55 to 75) preoperatively to 93.9 (range, 79 to 100) at the final follow-up (P<.001). 80% meniscus healing was found on arthroscopic or MRI follow up. Conclusively, arthroscopic repair using Popliteus tendon as a post is effective for treating young people with complex lateral meniscus tear as a salvage procedure.

• Advances in pediatric surgery
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• v.19 no.2
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• pp.108-121
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• 2013

목적 Pheochromocytoma of the Adrenal gland Scaled Score (PASS) 시스템과 면역화학염색 등을 통한 갈색세포종 및 부교감신경절종의 악성화 예측인자가 제시되고 있으나 명확한 병리학적 또는 분자생물학적 예측인자는 밝혀진 바 없다. 본 연구에서는 임상적, 병리학적 분석을 통해 갈색세포종 및 복강내 부교감신경절종의 악성화 예측인자를 확인하고자 하였다. 대상 및 방법 1990년 1월부터 2010년 12월까지 서울대학교어린이병원에서 수술적 절제 후 병리학적으로 갈색세포종 및 복강내 부교감신경절종으로 확진된 20명의 18세 이하 소아 환자를 대상으로 임상적 특징을 분석하였고, PASS 시스템에 따른 병리 슬라이드 판독하였다. 세포활성도를 반영한다고 알려진 유전자에 대한 항체 중 Ki-67, p53, bcl-2, mdm-2, cycline D1, p21, p27을 이용해 면역 화학검사를 한 후 결과를 확인하였다. 결과 20명의 환자 중 갈색세포종은 14명, 복강내 부교감신경절종은 6명이었다. 악성화는 각각 4명, 3명에서 관찰되었다. 혈관 침범, 주변부 지방조직 침습, 세포분열 증가가 통계적으로 유의한 악성화 예측인자였으며(각각 p=.007, .031, .031), 갈색세포종만 분석하였을 때도 통계적으로 유의하였다(각각 p=.033, .003, .019). PASS 시스템은 악성화를 예측하는데 있어 통계적으로 유의하지 않았으며, 혈관 침범, 주변부 지방조직 침습, 세포분열 증가를 항목으로 하여 새롭게 만든 병리 스코어 시스템은 악성 환자군과 양성 환자군 사이에 통계적으로 유의한 차이를 보였다(p< .001). 악성과 양성 질환 사이의 면역화학염색 결과에서 유의한 차이는 없었다. 결론 소아에서 갈색세포종 및 복강내 부교감신경절종의 악성화 예측인자로 혈관 침범, 주변부 지방조직 침습, 세포분열 증가를 이용할 수 있다. 소아에서 PASS시스템으로 악성화를 예측할 수 없었으나, 새로운 병리스코어 시스템으로 악성 환자군을 예측할 수 있었다. 면역화학검사 결과 세포 활성도를 반영하는 인자들은 악성화를 예측할 수 없었다.

• Journal of Astronomy and Space Sciences
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• v.17 no.2
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• pp.199-210
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• 2000

We present the results from narrow-band spectrophotometry of Comet Hale-Bopp (C/1995 O1) near perihelion obtained at Sobaeksan Optical Astronomy Observatory 61cm telescope equipped with PM 512 CCD camera(512$\times$512, 0.5"/pixel) and narrow-band filter set for the comet on 19 nights from February 21 to May 1, 1997. We discuss molecular emission band morphology and photometric behavior of Comet Hale-Bopp. The morphology of CN band shows more symmetric light distributions than $C_2$ or $C_3$ bands. On other hand, $C_2$ and $C_3$ band have more compact light distributions than CN band. Similar to wide-band image, molecular band morphology shows spiral structures at the core of the comet. The CN surface brightness variation with changing heliocentric distance shows difference from those of $C_2$ and $C_3$. The brightness, however, of these molecular bands near perihelion shows previously known 7day period light variations.