• Steel and Composite Structures
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• v.38 no.4
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• pp.381-397
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• 2021

Based on the spatial substructure hybrid simulation test (SHST) method, the seismic performance of a high-strength steel composite K-eccentrically braced frame (K-HSS-EBF) structure system is studied. First, on the basis of the existing pseudostatic experiments, a numerical model corresponding to the experimental model was established using OpenSees, which mainly simulated the shear effect of the shear links. A three-story and five-span spatial K-HSS-EBF was taken as the prototype, and SHST was performed with a half-scale SHST model. According to the test results, the validity of the SHST model was verified, and the main seismic performance indexes of the experimental substructure under different seismic waves were studied. The results show that the hybrid simulation results are basically consistent with the numerical simulation results of the global structure. The deformation of each story is mainly concentrated in the web of the shear link owing to shear deformation. The maximum interstory drifts of the model structure during Strength Level Earthquake (SLE) and Maximum Considered Earthquake (MCE) meet the demands of interstory limitations in the Chinese seismic design code of buildings. In conclusion, the seismic response characteristics of the K-HSS-EBFs are successfully simulated using the spatial SHST, which shows that the K-HSS-EBFs have good seismic performance.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.3032-3036
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• 2011

Cooling type of traction motor for EMU in domestic is mostly an open type. Its system is a cooling air entered through air inlet cool down a traction motor and an hot air by traction motor get out air outlet. It is easy to cool it down but hard to maintain it. To improve an ability of maintenance, a total enclosed type traction motor is already developed and used in abroad, not an opne type. So we developed a total enclosed type traction motor which will be used in domestic and abroad EMU. We tried to reduce a weight and a size compared with the abroad one. In contrast with open type traction motors which cool off inside of motors, total enclosed motors cool down by cooling exterior frame of motors. In this case, cooling fins or air fan blowing to the exterior of motors are applied. The total enclosed type traction motor developed by us have two housing to block the foreign substance into inner of a motor and have two cooling fan to easy to reduce a heat happened at a coil. In this paper, design of a cooling structure of the total enclosed traction motor developed twice and performance verification through test will be discussed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.4
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• pp.351-357
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• 2003

An easy learning elevator originated is opened to compare the existed teaming equipment, and it had a high studied efficiency that the sequence control circuit can open and close with the wire. The structure of equipment to be controlled from the first floor to the fifth floors is demostrated by the constructive apparatus with the lamps to express the function of the open-close of the door according to the cage moving with a mechanical actuation of the forward reverse breaker and the motor of load, and the mechanical actuation of hand-operation control components of push-button S/W and L/S and relay etc. These components let connect each other in order to control of the elevator function with the auto program and the designed sequence control circuit. Consequently the cage could go and come till 1∼5 steps with an auto program of the elevator and the sequence control circuit. The sequence control circuit is controlled by the step of forward and reverse to follow as that the sensor function of L/S1 ∼ L/S5 let posit with the control switchs of S/W1 ∼ S/W5 of PLC testing panel and switchs of S/W1 ∼ S/W5 installed on the transparent acryl plate of the frame. In here, improved apparatus is the hand-auto operation combined learning equipment to study the principle and technique of the originate sequence control circuit and the auto program of PLC.

• Journal of Korean Association for Spatial Structures
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• v.11 no.2
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• pp.129-138
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• 2011

Construction methods for underground structure are classified as bottom-up, up-up, and top-down methods depending on the procedure of construction related to a superstructure. In top-down construction methods, building's main structure is built from the ground level downwards by sequentially alternating ground excavation and structure construction. In the mean time, the main structure is also used as supporting structure for earth-retaining wall, which results in the increased stability of the earth-retaining wall due to the minimized deformation in adjacent structures and surrounding grounds. In addition, the method makes it easy to secure a field for construction work in the downtown area by using each floor slabs as working spaces. However top-down construction method is often avoided since an excavation under the slab has low efficiency and difficult environment for work, and high cost compared with earth anchor method. This paper proposes a combined construction method where semi-open cut is selected as excavation work, slurry as earth -retaining wall and CWS as top-down construction method. In the case study targeted for an actual construction project, the proposed method is compared with existing top-down construction method in terms of economic feasibility, construction period and work efficiency. The proposed construction method results in increased work efficiency in the transportation of earth and sand, and steel frame erection, better quality management in PHD construction, and reduced construction period.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.11
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• pp.1576-1584
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• 2016

Acetyl xylan esterase (AXE), which hydrolyzes the ester linkages of the naturally acetylated xylan and thus known to have an important role for hemicellulose degradation, was isolated from the anaerobic rumen fungus Neocallimastix frontatlis PMA02, heterologously expressed in Escherichi coli (E.coli) and characterized. The full-length cDNA encoding NfAXE1 was 1,494 bp, of which 978 bp constituted an open reading frame. The estimated molecular weight of NfAXE1 was 36.5 kDa with 326 amino acid residues, and the calculated isoelectric point was 4.54. The secondary protein structure was predicted to consist of nine ${\alpha}$-helixes and 12 ${\beta}$-strands. The enzyme expressed in E.coli had the highest activity at $40^{\circ}C$ and pH 8. The purified recombinant NfAXE1 had a specific activity of 100.1 U/mg when p-nitrophenyl acetate (p-NA) was used as a substrate at $40^{\circ}C$, optimum temperature. The amount of liberated acetic acids were the highest and the lowest when p-NA and acetylated birchwood xylan were used as substrates, respectively. The amount of xylose released from acetylated birchwod xylan was increased by 1.4 fold when NfAXE1 was mixed with xylanase in a reaction cocktail, implying a synergistic effect of NfAXE1 with xylanase on hemicellulose degradation.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.430-435
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• 1992

Hazard identification is one of the most important task in process design and operation. This work has focused on the development of a knowledge-based expert system for HAZOP (Hazard and Operability) studies which are regarded as one of the most systematic and logical qualitative hazard identification methodologies but which require a multidisciplinary team and demand much time-consuming, repetitious work. The developed system enables design engineers to implement existing checklists and past experiences for safe design. It will increase efficiency of hazard identification and be suitable for educational purposes. This system has a frame-based knowledge structure for equipment failures/process material properties and rule networks for consequence reasoning which uses both forward and backward chaining. To include wide process knowledge, it is open-ended and modular for future expansion. An application to LPG storage and fractionation system shows the efficiency and reliability of the developed system.

• Korean Institute of Interior Design Journal
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• no.32
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• pp.13-20
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• 2002

This study is purposed to find fundamental characteristics in Grassi's architecture which has architectural principles in architecture itself and in the general frame of the historical facts of architecture. His architectural theories can be explained for rationality, historicity, universality. The method of architectural composition can be divided into urban morphological characteristic and compositional characteristic of architecture. The characteristics of the former are the reconstruction of the urban structure by the readjustment of an urban axis which is based on historical continuity of the city, the open court which is a passage transformed from colonnade that is the historical vernacular type and the respect for the city-line which goes with historical context. The characteristics of the latter are the use transformed of nine square which gives consideration to centrality and typology at the same time and the hierarchic division of the principal space and the subordinate space for the functional typical purpose. This analysis shows that Grassi's architecture is on the base of historical continuity and urban reality and for him architectural work is mental work which conflict with the real world for the reconstruction of the city.

• Steel and Composite Structures
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• v.47 no.5
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• pp.663-677
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• 2023

The self-centering energy-dissipating coupled wall panels (SECWs) possess a dual capacity of resiliency and energy dissipation. Used in steel frames, the SECWs can localize the damage of structures and reduce residual drifts. Based on OpenSEES, the nonlinear models were established and validated by experimental results. The seismic design procedure of steel frame with SECW structures (SF-SECW) was proposed in accordance with four-level seismic fortification objectives. Nonlinear time-history response analyses were carried out to validate the reasonability of seismic design procedure for 6-story and 12-story structures. Results show that the inter-story drifts of designed structures are less than drift limits. According to incremental dynamic analyses (IDA), the fragility curves of mentioned-above structure models under different limit states were obtained. The results indicate that designed structures have good seismic performance and meet the seismic fortification objectives.

• Molecules and Cells
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• v.26 no.4
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• pp.404-408
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• 2008

The genome of replication-competent BERV ${\gamma}4$ provirus, which is the most abundant ERV family in the bovine genome, was characterized in detail. The BERV ${\gamma}4$ genome showed that BERV ${\gamma}4$ harbors 8576 nucleotides and has the typical 5'-long terminal repeat (LTR)-gag-pro-pol-env-LTR-3' retroviral organization with a long leader region positioned before the gag open reading frame. Multiple sequences analysis showed that the nucleotide difference between 5' and 3' LTRs was 4.2% (mean value 0.042) in average, suggesting that the provirus formed at most 13.3 million years ago. Gag separated by a stop codon from pro-pol in the same reading frame, while env resides in another reading frame lacking of a functional surface domain. According to the current bovine genome sequence assembly, the full-length BERV ${\gamma}4$ provirus sequences were only found in the chromosomes 1, 2, 6, 10, 15, 23, 26, 28, X, and unassigned, although the partial sequences almost evenly distributed in the entire bovine genome. This is the first detailed study describing the genome structure of BERV ${\gamma}4$, the most abundant ERV family present in bovine genome. Combined with our recent reports on characterization of ERVs in bovine, this study will contribute to illuminate ERVs in the cattle of which no information was previously available.

• Structural Engineering and Mechanics
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• v.77 no.2
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• pp.197-215
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• 2021

Under a severe environment of multiple hazards such as earthquakes and winds, the life-cycle performance of engineering structures may inevitably be deteriorated due to the fatigue effect caused by long-term exposure to wind loads, which would further increase the structural vulnerability to earthquakes. This paper presents a framework for evaluating the lifetime structural seismic performance under the effect of wind-induced fatigue considering different sources of uncertainties. The seismic behavior of a high-rise steel-concrete composite frame with buckling-restrained braces (FBRB) during its service life is systematically investigated using the proposed approach. Recorded field data for the wind hazard of Fuzhou, Fujian Province of China from Jan. 1, 1980 to Mar. 31, 2019 is collected, based on which the distribution of wind velocity is constructed by the Gumbel model after comparisons. The OpenSees platform is employed to establish the numerical model of the FBRB and conduct subsequent numerical computations. Allowed for the uncertainties caused by the wind generation and structural modeling, the final annual fatigue damage takes the average of 50 groups of simulations. The lifetime structural performance assessments, including static pushover analyses, nonlinear dynamic time history analyses and fragility analyses, are conducted on the time-dependent finite element (FE) models which are modified in lines with the material deterioration models. The results indicate that the structural performance tends to degrade over time under the effect of fatigue, while the influencing degree of fatigue varies with the duration time of fatigue process and seismic intensity. The impact of wind-induced fatigue on structural responses and fragilities are explicitly quantified and discussed in details.