• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.3
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• pp.253-260
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• 2016

In this paper, the optimal seismic design method for inducing the beam-hinge collapse mechanism of steel moment frames is presented. This uses the non-dominated sorting genetic algorithm II(NSGA-II) as an optimal algorithm. The constraint condition for preventing the occurrence of plastic hinges at columns is used to induce the beam-hinge collapse mechanism. This method uses two objective functions to minimize the structural weight and maximize the dissipated energy. The proposed method is verified by the application to nine story steel moment frame example. The minimum column-to-beam strength ratio to induce the beam-hinge collapse mechanism are investigated based on the simulation results. To identify the influence of panel zone on the minimum column-to-beam strength ratio, three analytic modeling methods(nonlinear centerline model without rigid end offsets, nonlinear centerline model with rigid end offsets, nonlinear model with panel zones) are used.

• Journal of Families and Better Life
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• v.27 no.2
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• pp.155-171
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• 2009

This study was designed to examine the use of housing in modern Korea, and to draw the interrelation of people and housing. In-depth interviews were conducted, and the qualitative research investigated various aspects of housing history among four individuals during the different phases of social and economic transitions. 4 narratives showed the unique characteristics of life history, and the findings indicated that the housing experiences were closely related to hometown, the relation to birth family at postmarriage, economic status, and the meaning of home. The main findings were as follows: the validity to select the interviewers was proved in that the selection was based on both housing structure type and ownership, and also the research indicated that economic status and housing structure type influenced the entire housing experience of each interviewee. The use of housing varied and the implications of housing lied in social and economic contexts. The use of housing, of which the term was contrived to alternatively described housing consumption modes, and chronology were affected by such individual factors as economic status, familiar relationships, residential location, the meaning and subjectivity of housing.

• Journal of the Korean earth science society
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• v.27 no.5
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• pp.569-578
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• 2006

The distribution and kinematic information of the continuum, $H{\alpha},\;H{\beta}$, [O III], & [N II] images based on spectroscopic data secured with the OASIS at the Hawaii CFHT 3.6m telescope have been analyzed to study the physical characteristics of NGC 5728. The three bright regions-northwestern knot, southeastern knot, and the nucleus-exist within a $15"{\times}12"$ sky area which seem to indicate gas flows along the northwestern or western direction from the nucleus. We find that the center of a 10" diameter ring is at the northwestern knot, not at the galactic center. To further analyze the formation mechanism of such a ring, the kinematics of the nucleus and knot have been studied and the central structure of the Active Galactic Nuclei has been investigated by comparing various emission images.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.173-179
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• 2005

In succession to previous study(A Study on the Limit of Anchor Dragging for Ship at Anchor sim I), the experiment of anchor dragging by ship handling simulator was performed to investigate the anchoring stability of ship at anchor in this study. The purpose of this experiment is to check the behavior charateristics of ship being dragged and the limit of anchor dragging for ship at anchor. A small tanker ship, which had been anchored in Jinhae Bay when the typhoon MAEMI passed on September 2003, was chosen as model ship for the experiment of anchor dragging and the result of experiment was confirmed to be very similar to the result of theoretical review and field report.

• Journal of the Korean Ceramic Society
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• v.47 no.6
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• pp.515-523
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• 2010

Porous SiC candle filter preforms were fabricated by extrusion and ramming process. To fabricate SiC candle filter preform, commercially available F180 mesh ($85\;{\mu}m$) $\alpha$-SiC powder and $44\;{\mu}m$ mullite, $CaCO_3$ powder were used as the starting materials. The candle type preforms were fabricated by vacuum extrusion and ramming process, and sintered at $1400^{\circ}C$ 2 h in air atmosphere. Corrosion test of the sintered candle filter specimens as forming method was performed at $600^{\circ}C$ for 2,400 h in simulated IGCC syngas atmosphere. The effect of forming method on mechanical properties, pore distribution, microstructure and crystalline phase was investigated.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.1
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• pp.154-158
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• 2001

We tried to find out the information which can be drawn from the survey of general anesthesia in pediatric clinic at Seoul National University dental hospital from 1997 to 1999. The subjects were 37 patients Collected data were primary reasons for general anesthesia, preoperative physical status, age distribution, peformed dental treatment, complications, follow-up, and etc. Following were the results: (1) Most(97%) of patients treated under general anesthesia were handicapped and preoperative physical status was ASA Class I or Class II. (2) Majority(41%) of patients were between 11 and 15. (3) Average of 8.1teeth were restored and 3.3teeth were extracted. (4) In 32% of patients, there were mild complications. (5) 12(32%) of the patients responded to the six-month recall check.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.4
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• pp.524-530
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• 2002

Micro electric spark discharge device was fabricated on a FOTURAN glass wafer using MEMS processing technique and its performance of electron discharge and subsequent formation of ignition kernel were tested. Micro electric spark device is an essential subsystem of a power MEMS that has been under development in this laboratories. In a combustion chamber of sub millimeter scale depth, spark electrodes are formed by electroplating Ni on a base plate of FOTURAN glass wafer. Optimization of spark voltage and spark gap is crucial for stable ignition and endurance of the electrodes. Namely, wider spark gaps insures stable ignition but requires higher ignition voltage to overcome the spark barrier. Also, electron discharge across larger voltage tends to erode the electrodes limiting the endurance of the overall system. In the present study, the discharge characteristics of the proptotype ignition device was measured in terms of electric quantities such as voltage and currant with spark gap and end shape as parameters. Discharge voltage shows a little decrease in width of less than 50㎛ and increases with electrode gap size. Reliability test shows no severe damage over 10$\^$6/ times of discharge test resulting in satisfactory performance for application to proposed power MEMS devices.

• Journal of the Korean Chemical Society
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• v.40 no.10
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• pp.649-655
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• 1996

The chemical behaviour of Pt(Ⅱ) and Pd(Ⅱ) complexes with the organic ligand tetramethylenesulfoxide(TMSO) has been investigated by UV/vis-spectrophotometric, magnetic, and electrochemical methods. Two energy absorption bands are observed in the spectra of these complexes. The crystal field splitting energy, spin pairing energy, and bond strength were obtained from the spectra of the complexes. The electronic properties of the complexes are found to be delocalized, and low-spin state. The correlation between ligand and metals were strong bonding strength. These complexes are diamagnetics. The redox reaction processes of the complexes were investigated by cyclic voltammetry in an aprotic solvent. The redox processes of complexes turned out to be respect to one-electrton one step. These complexes were considerably diffusion and reaction controlled.

• Korean Journal of Agricultural Science
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• v.38 no.3
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• pp.421-428
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• 2011

Of the countries where Korea has advanced for overseas afforestation investments, Indonesia might be the most important country. As the end of 2010, nine Korean companies have been implementing afforestation projects in Indonesia, covering a total area of one hundred and fifty thousand hectares roughly. Following the Memorandum Of Understanding (MOU) on afforestation investment covering five hundred thousand hectares (A/R CDM / industrial afforestation) signed between Korea and Indonesia, the two countries concluded in 2009 an additional MOU covering two hundred thousand hectares for biomass afforestation, thus securing a total afforestation area of seven hundred thousand hectares. Further it was guaranteed that afforestation license would have validity for maximum 95 years, which laid the foundation for long-term stable investments for afforestation projects. Forest law of Indonesia consists of Presidential decree and Governmental decree as superior regulations and Minister's decree as subordinate regulations, being made up of total 17 chapters. Forestry Minister's decree was amended at end of last year, as regards license for exploitation of timber and forestry products in afforestation area. In the past, such license to develop and use timber and forestry products had been granted under Forestry Minister's decree No. P 11 / Menhut-II / 2008. After the amendment in 2010, however, the ground was shifted to Forestry Minister's decree No. P 50 / Menhut-II / 2010, trimming the procedure to obtain afforestation license into a little simplified one.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.336-339
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• 2006

This study was conducted to provide the genetic diversity on Safflower collections and to identify the variations which could be utilized in Safflower breeding. The RAPDs analysis was used to clarify the genetic relationships among 32 Safflower collections. Among 37 primers applied in RAPD analysis, 25 primers that generated appropriate PCR products for identification of the genetic characters in safflower collections were used. Amplified PCR showed the highly reproducible bands at $0.1{\sim}4.0kb$. The number of bands amplified in each primer showed the variations ranging from 1 to 9, with the average of 5.6. A total of 25 bands were identified among twenty-five selected primers and 23 bands (19.2%) showed polymorphism. Based on the similarity value of 0.042 in dendrogram derived from the cluster analysis, the 32 Safflower collections were classified into 6 groups. The two main groups, II and III included 12 collections (38%) and 12 collections (38%), respectively.