• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.131-131
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• 2003

Surface micromachined uncooled IR detector with the optimized VOx bolometric layer was fabricated based on sandwich structure of the V$_2$O$_{5}$V/V$_2$O$_{5}$. In order to improve the detectivity of the IR detector, we optimized a few factors in the viewpoint of bolometric material. Vanadium oxide thin film is a promising material for uncooled microbolometers due to its high temperature coefficient of resistance at room temperature. It is, however, very difficult to deposit vanadium oxide thin films having high temperature coefficient of resistance and low resistance because of process limits in microbolometer fabrication. In order to increase the responsivity and decrease noise, we increase TCR of bolometric material and decrease room temperature resistance based on the sandwich structure of the V$_2$O$_{5}$V/V$_2$O$_{5}$ by conventional sputter. By oxygen diffusion through low temperature annealing of V$_2$O$_{5}$V/V$_2$O$_{5}$ in oxygen ambient, various mixed phase vanadium oxide was formed and we obtained TCR in range of-1.2 ~-2.6%/$^{\circ}C$ at room temperature resistance of 5~100k$\Omega$.mega$.

• Explosives and Blasting
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• v.25 no.2
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• pp.11-21
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• 2007

The main structure of Gunsan steam power station was demolished by the toppling method using high explosives. Height of a main building is 58m and a total floor area is $292,000m^2$. It is Rahmen(rigid-frame) structure consisted of almost columns and beams and slabs exist only in one part of the building for the electricity generators equipments. To improve the efficiency of blasting work, it is separated into 4 sectors. Blasting floors were 1, 2, 3, & 4 stories from first sector to third sector, while 1, 2, 5, & 7 of fourth sector were blasted because it had not slabs. About 102.675 kg of the MegaMITE were used with 225 electric detonator and 638 non-electric detonators to check detonator connection and confidence of detonation. The blasting noise and vibration were monitored to evaluate the environment effect and the damage of the nearby structures.

• Land and Housing Review
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• v.2 no.1
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• pp.47-52
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• 2011

Recent advances of technology in materials science have made it easy to respond to user's needs on high performance steel in civil and building structures. The high-performance and high-strength steel are required for large scale structure and high-rise building to have high-strength, high fracture toughness and better weldability etc. Therefore development of 600MPa class steel for mega structure is necessary. high strength steels, however, may have mechanical properties that are significantly different from those of the conventional steels. The application of high-strength steels to building structures should be reviewed as to whether inelastic behavior equivalent to that of conventional steels can be attained or not. This study researched the structural behavior of high strength circular tubes compression and under flexure. Three column tests and three flexural tests were carried out. The suitability of existing design formulae(KBC 2009) and the structural behavior were investigated through these columns and beams with various types.

• Journal of the Korean Geographical Society
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• v.46 no.2
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• pp.181-196
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• 2011

The purpose of this study is to explore the network city in detail as a new model for explaining urban growth in the changing economic environment in recent years. For this purpose, starting from Batten's (1995) pioneering work on network city in the mid 1990s to the most recent ones, literature is reviewed and various aspects of network city model are examined including formation process, spatial structure, application to management and urban planning, and growth potential. With this, the study aims at providing comprehensive knowledge necessary for evaluating if the network city model is appropriate in explaining the urban phenomena in the 21st century. The result of the review shows that network city model is the one appropriately explaining the changing urban system associated with the economic globalization and the development of transport and information technology. In addition, more and more European city governments tend to adopt this as the urban planning principle.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.6
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• pp.595-602
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• 2009

Great number of ships has been built by Korean Shipyards since early of 2,000 due to the expanding worldwide trade. Most of shipyards have enlarged the weight of erection block and many blocks have been assembled in block fabrication factories outside the shipyards to reduce the shipbuilding period. Especially, Giga blocks that exceed 2,000 tons are often assembled by the block fabrication factories outside the shipyard. Generally, the blocks are transported to building dock in shipyard by towing barges. Accident can be occurred during the sea transportation and it may bring about not only the delay of delivery but also a disaster on the ocean environments. Transportation condition of GPE (Grand Pre-Erection) block differs from the ocean going conditions of marine vessels. Special consideration should be included before transportation work in order to guarantee the safety of GPE blocks and barge carriers. In this paper, several examples, which have been investigated to set up the safety standard of transportation of the GPE blocks on coastal routes, are introduced. For the barge transportation on coastal sea route, the design criteria are discussed, considering the design wave, the acceleration induced by wave, structural strength, and the fixture condition of blocks.

• Genomics & Informatics
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• v.20 no.2
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• pp.19.1-19.15
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• 2022

Alfalfa (Medicago sativa) is an important food and feed crop which rich in mineral sources. The WUSCHEL-related homeobox (WOX) gene family plays important roles in plant development and identification of putative gene families, their structure, and potential functions is a primary step for not only understanding the genetic mechanisms behind various biological process but also for genetic improvement. A variety of computational tools, including MAFFT, HMMER, hidden Markov models, Pfam, SMART, MEGA, ProtTest, BLASTn, and BRAD, among others, were used. We identified 34 MsWOX genes based on a systematic analysis of the alfalfa plant genome spread in eight chromosomes. This is an expansion of the gene family which we attribute to observed chromosomal duplications. Sequence alignment analysis revealed 61 conserved proteins containing a homeodomain. Phylogenetic study sung reveal five evolutionary clades with 15 motif distributions. Gene structure analysis reveals various exon, intron, and untranslated structures which are consistent in genes from similar clades. Functional analysis prediction of promoter regions reveals various transcription binding sites containing key growth, development, and stress-responsive transcription factor families such as MYB, ERF, AP2, and NAC which are spread across the genes. Most of the genes are predicted to be in the nucleus. Also, there are duplication events in some genes which explain the expansion of the family. The present research provides a clue on the potential roles of MsWOX family genes that will be useful for further understanding their functional roles in alfalfa plants.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.1
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• pp.72-80
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• 2015

In this study, comparative analysis has been performed with regard to a bending stress and deformation at bottom slab of a concrete floating container terminal by live load distributions. In addition, a structural performance and behavior of the floating structure is considered using a numerical analysis. Through reviewed structural performance of a floating structure by live load distribution, the structure presented tensile behavior by two live load cases (A, B, D-type). Then, the other live load cases (C, E, F, G, H, I, J-type) shows compressive behavior. Especially, immoderately compressive stress was generated on bottom slab at specific load distribution. but, that should be decreased through controling buoyancy pre-flexion. Through reviewed structural behavior, slopes of structure by four live load cases (B, E, F, H-type) were exceeded in design criteria of mega-float. It should be estimated that it get out of the load case at loading container. In all, the present study can be considered as a benchmark of a floating container terminal in the absence of analysis and will be used to guide-line about serviceability of concrete floating container terminal.

• Journal of Korean Society of Steel Construction
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• v.25 no.5
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• pp.569-578
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• 2013

In a super-tall building construction, thick and large-sized embed plates are usually used to connect mega structural steel members to RC core wall or columns by welding a gusset plate on the face of the embed plate with T-shape. A large amount of heat input accumulated by weld passes causes the plates to expand or deform. In addition, the temperature of concrete around the plates also could be increased. Consequently, cracks and spalls occur on the concrete surface. In this study, the effect of weld heat on embed plates and 80MPa high strength concrete is investigated by considering weld position (2G and 3G position), edge distance, concrete curing time, etc. Measured temperature of the embed plates was compared with the transient thermal analysis results. Finally, push-out tests were performed to verify and compare the shear studs capacity of the embed plate with design requirement. Test result shows that the shear capacity of the plate is reduced by 14%-19% due to the weld heat effect and increased as the concrete curing time is longer.

• Bulletin of the Korean Space Science Society
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• 2008.10a
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• pp.38.1-38.1
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• 2008

Tides caused by the Galactic gravitational field affect the current dynamical structure of globular clusters in the Galaxy. Indeed, the observed feature of tidal tails stretching beyond globular clusters' tidal radii provides a key information of interaction with the gravitational field of the Galaxy and kinematical orbit of the clusters, which can be an evidence of the merging scenario of the Galaxy formation and evolution. To find such a tidal feature, we have studied spatial density distribution of stars around five globular clusters in the Galactic halo and one cluster in the Galactic bulge, for which we have used wide-field deep photometric data of gri and JHK bands obtained from the MegaCam and WIRCam of the CFHT. Applying the statistical contrast filtering of field stars in the color-magnitude plane of detected stars around five halo clusters, we have found features of tidal tails for four clusters M53, M15, NGC 5053, and NGC 5466. The detected over-density tidal features are well aligned with the cluster's orbits and stretched into the direction of the Galactic center. Statistical analysis indicate that these tidal tails are believed to be cluster stars that have escaped due to the tidal effects to the clusters. A similar tidal feature to that of halo clusters is also detected for the bulge cluster NGC 6626, while the over-density feature seems to be extended into the Galactic plane rather than into the orbital direction and the Galactic center. Conclusively, our result adds further observational evidence of the merging scenario of the Galaxy formation and evolution.

• Korean Journal of Construction Engineering and Management
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• v.13 no.2
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• pp.80-90
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• 2012

In 2011, the overall construction markets in KOREA are highly depressed due to decreases in orders of domestic construction markets in both private and public field. Also, we are losing competitive advantages over Chinese and Indian companies owing to the market shares on plant construction projects excessively. It is recognizable, under the circumstances that we are in interior position on high value technique to other advanced countries, that the orders of mega building and plant construction projects tend to be placed through the" Pre-construction Service", the importance of which has been emphasized domestically and internationally in recent time. However, current domestic construction companies show scarcity in understanding the general idea of the Pre-construction Service and fail in building proper structure of it. It is obvious that they cannot have any competent strategy to deal with Pre-construction Service. The Purpose of this paper is to analyze the core competence throughout preconstruction phase and, and make up for the weakness in the current pre-construction service process.