• Title/Summary/Keyword: ${\delta}$ frame

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Numerical investigation on seismic behaviors of midrise special moment resistant frame retrofitted by timber-base bracings

  • Ainullah-Mirzazadah, Ainullah-Mirzazadah;Sabbagh-Yazdi, Saeed-Reza
    • Steel and Composite Structures
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    • v.45 no.1
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    • pp.83-100
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    • 2022
  • Timber is one of the few natural, renewable building materials and glulam is a type of engineering wood product. In the present work, timber-based braces are applied for retrofitting midrise Special Moment Resisting Frame (SMRF) using two types of timber base braces (Timber base glulam, and hybrid Timber-Steel-BRB) as alternatives for retrofitting by traditional steel bracings. The improving effects of adding the bracings to the SMRF on seismic characteristics of the frame are evaluated using load-bearing capacity, energy dissipation, and story drifts of the frame. For evaluating the retrofitting effects on the seismic performance of SMRF, a five-story SMRF is considered unretofitted and retrofitted with steel-hollow structural section (HSS) brace, Glued Laminated Timber (Glulam) brace, and hybrid Timber-Steel BRB. Using OpenSees structural analyzer, the performance are investigated under pushover, cyclic, and incremental loading. Results showed that steel-HSS, timber base Glulam, and hybrid timber-steel BRB braces have more significant roles in energy dissipation, increasing stiffness, changing capacity curves, reducing inter-story drifts, and reducing the weight of the frames, compared by steel bracing. Results showed that Hybrid BRB counteract the negative post-yield stiffness, so their use is more beneficial on buildings where P-Delta effects are more critical. It is found that the repair costs of the buildings with hybrid BRB will be less due to lower residual drifts. As a result, timber steel-BRB has the best energy dissipation and seismic performance due to symmetrical and stable hysteresis curves of buckling restrained braces that can experience the same capacities in tension and compression.

Limitation of effective length method and codified second-order analysis and design

  • Chan, S.L.;Liu, Y.P.;Zhou, Z.H.
    • Steel and Composite Structures
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    • v.5 no.2_3
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    • pp.181-192
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    • 2005
  • The effective length method for flexural (column) buckling has been used for many decades but its use is somewhat limited in various contemporary design codes to moderately slender structures with elastic critical load factor (${\lambda}_{cr}$) less than 3 to 5. In pace with the use of higher grade steel in recent years, the influence of buckling in axial buckling resistance of a column becomes more important and the over-simplified assumption of effective length factor can lead to an unsafe, an uneconomical or a both unsafe and uneconomical solution when some members are over-designed while key elements are under-designed. Effective length should not normally be taken as the distance between nodes multiplied by an arbitrary factor like 0.85, 1.0, 2.0 etc. Further, the classification of non-sway and sway-sensitive frames makes the conventional design procedure tedious to use and, more importantly, limited to simple regular frames. This paper describes the practical use of second-order analysis with section capacity check allowing for $P-{\delta}$ and $P-{\Delta}$ effects together with member and system imperfections. Most commercial software considers only the $P-{\Delta}$ effect, but not member and frame imperfections nor $P-{\delta}$ effect, and engineers must be very careful in their uses. A verification problem is also given for validation of software for this type of powerful second-order analysis and design. It is a trend for popular and advanced national design codes in using the second-order analysis as a norm for analysis and design of steel structures while linear analysis may only be used in very simple structures.

Molecular Characterization, Chromosomal Localizations, Expression Profile, and Association Analysis of the Porcine PECI Gene with Carcass Traits

  • Gao, H.;Fan, B.;Zhu, M.J.;Liu, Bang
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.1
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    • pp.7-12
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    • 2010
  • The full-length cDNA of the porcine peroxisomal ${\Delta}^3$,${\Delta}^2$-enoyl-CoA isomerase (PECI) gene encodes a monofunctional peroxisomal ${\Delta}^3$,${\Delta}^2$-enoyl-CoA isomerase. Cloning and sequencing of the porcine PECI cDNA revealed the presence of an 1185-base pair open reading frame predicted to encode a 394-amino acid protein by the 5'rapid amplification of cDNA ends (5'RACE) and EST sequences. The porcine PECI gene was expressed in seven tissues (heart, liver, spleen, lung, kidney, skeletal muscle, fat) which was revealed by reverse transcriptase-polymerase chain reaction (RT-PCR). The porcine PECI was mapped to SSC71/2 p11-13 using the somatic cell hybrid panel (SCHP) and the radiation hybrid panel (RH) (LOD score 12.84). The data showed that PECI was closely linked to marker S0383. A C/T single nucleotide polymorphism in PECI exon 10 (3'UTR) was detected as a PvuII PCR-RFLP. Association analysis in our experimental pig population showed that different genotypes of PECI gene were significantly associated with the Average Backfat thickness (ABF) (p<0.05) and Buttock backfat thickness (p<0.01).

Nonlinear Dynamic Analysis of Space Steel Frames (공간 강뼈대 구조물의 비선헝 동적 해석)

  • Kim Seung-Eock;Cuong Ngo-Huu;Lee Dong-Ho
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.18 no.4 s.70
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    • pp.395-404
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    • 2005
  • This paper presents a reliable numerical procedure for nonlinear time-history analysis of space steel frames subjected to dynamic loads. Geometric nonlinearities of member (P-$\delta$) and frame (P-$\Delta$) are taken into account by the use of stability functions in framed stiffness matrix formulation. The gradual yielding along the member length and over the cross section is included by using a tangent modulus concept and a softening plastic hinge model based on the New-Orbison yield surface. A computer program utilizing the average acceleration method for the integration scheme is developed to numerically solve the equation of motion of framed structure formulated in an incremental form. The results of several numerical examples are compared with those derived from using beam element model of ABAQUS program to illustrate the accuracy and the computational efficiency of the proposed procedure.

Recombinant Production of an Inulinase in a Saccharomyces cerevisiae gal80 Strain

  • Lim, Seok-Hwan;Lee, Hong-Weon;Sok, Dai-Eun;Choi, Eui-Sung
    • Journal of Microbiology and Biotechnology
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    • v.20 no.11
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    • pp.1529-1533
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    • 2010
  • The inulinase gene (INU1) from Kluyveromyces marxianus NCYC2887 was overexpressed by using the GAL10 promotor in a ${\Delta}ga180$ strain of Saccharomyces cerevisiae. The inulinase gene lacking the original signal sequence was fused in-frame to a mating factor ${\alpha}$ signal sequence for secretory expression. Use of the ${\Delta}ga180$ strain allowed for the galactose-free induction of inulinase expression using a glucose-only medium. Shake-flask cultivation in YPD medium produced 34.6 U/ml of the recombinant inulinase, which was approximately 13-fold higher than that produced by K. marxianus NCYC2887. It was found that the use of the ${\Delta}ga180$ strain improved the expression of inulinase in the recombinant S. cerevisiae in both aerobic and anaerobic conditions by about 2.9- and 1.7-fold, respectively. A 5-l fed-batch fermentation using YPD medium was performed under aerobic condition with glucose feeding, which resulted in the inulinase production of 31.7 U/ml at the $OD_{600}$ of 67. Ethanol fermentation of dried powder of Jerusalem artichoke, an inulin-rich biomass, was also performed using the recombinant S. cerevisiae expressing INU1 and K. marxianus NCYC2887. Fermentation in a 5-l scale fermentor was carried out at an aeration rate of 0.2 vvm, an agitation rate of 300 rpm, and with the pH controlled at 5.0. The temperature was maintained at $30^{\circ}C$ and $37^{\circ}C$, respectively, for the recombinant S. cerevisiae and K. marxianus. The maximum productivities of ethanol were 59.0 and 53.5 g/l, respectively.

Numerical modelling of the behavior of bare and masonry-infilled steel frames with different types of connections under static loads

  • Galal Elsamak;Ahmed H. Elmasry;Basem O. Rageh
    • Computers and Concrete
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    • v.33 no.1
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    • pp.103-119
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    • 2024
  • In this paper, the non-linear behavior of masonry-infill and bare steel frames using different beam-column connections under monotonic static loading was investigated through a parametric study. Numerical models were carried out using one- and two-dimensional modelling to validate the experimental results. After validating the experimental results by using these models, a parametric study was carried out to model the behavior of these frames using flushed, extended, and welded connections. The results showed that using the welded or extended connection is more efficient than using the flushed type in masonry-infilled steel frames, since the lateral capacities, initial stiffness, and toughness have been increased by 155%, 601%, and 165%, respectively in the case of using welded connections compared with those used in bare frames. The FE investigation was broadened to study the influence of the variation of the uniaxial column loads on the lateral capacities of the bare/infill steel frames. As the results showed when increasing the amount of uniaxial loading on the columns, whether in tension or compression, causes the lateral load capacity of the columns to decrease by 26% for welded infilled steel frames. Finally, the influence of using different types of beam-to-column connections on the vertical capacities of the bare/infill steel frames under settlement effect was also studied. As a result, it was found that, the vertical load capacity of all types of frames and with using any type of connections is severely reduced, and this decrease may reach 62% for welded infilled frames. Furthermore, the flushed masonry-infilled steel frame has a higher resistance to the vertical loads than the flushed bare steel frame by 133%.

Mating Disruption of Grapholita molesta by RNA Interference of a Fatty Acid Desaturase Expressed in Adult Abdomen (복숭아순나방 성충 복부에서 발현하는 불포화효소의 RNA 간섭과 교미교란)

  • Kim, Kyusoon;Jung, Chung Ryul;Yang, Chang Yeol;Kwon, Gimyeon;Kim, Yonggyun
    • Korean journal of applied entomology
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    • v.56 no.1
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    • pp.61-67
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    • 2017
  • Two major sex pheromone components (Z-8-dodecenyl acetate and E-8-dodecenyl acetate) are known in the peach fruit moth, Grapholita molesta. From a putative biosynthetic pathway of these sex pheromone components, delta 10 desaturase ($10{\Delta}$ DES) has been proposed to play a crucial role in synthesizing a species-specific stereoisomer of the double bond. However, its molecular identity was not known. This study determined a putative desaturase (Gm-comp1575) as a $10{\Delta}$ DES candidate from G. molesta transcriptome constructed from the sex pheromone gland. Its open reading frame encodes 370 amino acid sequence with a predicted molecular weight at 43.2 kDa and isoelectric point at 8.77. It was predicted to have four transmembrane domains and six glycosylation sites at N-terminal or cytosolic domains. A phylogenetic analysis with its predicted amino acid sequence indicated that Gm-comp1575 is closely related with known $10{\Delta}$ DES genes of other insects. Gm-comp1575 transcript was detected in female adults at sex pheromone gland and other abdominal tissues. RNA interference of Gm-comp1575 significantly reduced attractiveness of virgin females in apple orchard compared to control females. These results suggest that Gm-comp1575 is associated with sex pheromone biosynthesis of G. molesta.

Preparation and Characterization of Salmon Patty using Muscle from Salmon Frame (연어 frame 유래 근육을 이용한 연어 패티의 제조 및 특성)

  • Heu, Min-Soo;Kim, Jin-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.42 no.3
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    • pp.183-189
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    • 2009
  • This study was conducted to prepare salmon patty using muscle separated from salmon frame (SPFM) and to investigate the food component characterization. When compared to salmon patty with fillet muscle (SPM), SPFM was lower in the moisture content, while it was higher in crude lipid content. However, no differences in the ash and protein contents between SPFM and SPM were found. Compared to SPM, the Hunter color value in cross section of cooked SPFM was higher in a and $\Delta$E values, while the color was lower in Land b values. Trichloroacetic acid soluble-N content of SPFM was 279 mg/100 g, which was insignificantly different (P>0.05) compared to those of SPM and commercial patty. The hardness of SPFM was 0.44 kg/$cm^2$, which was insignificantly different (P>0.05) compared to that of SPM, while was higher than that of commercial patty. The major fatty acids of SPFM were 16:0 (16.5%), 18:1n-9 (29.2%) and 18:2n-6 (26.1%). The 20:5n-3 and 22:6n-3 were also detected in high composition. The total amino acid content of SPFM was 16.6 g/100 g, which was similar to that of SPM. However, the total amino acid of SPFM was 14% higher than that of commercial patty. From the results of the mineral content, SPFM was higher than that of SPM in Fe and Ca, while the K in SPFM was lower. According to the result of sensory evaluation on the color, flavor and taste, no significant differences in all sensory items between SPFM and SPM were found.

A Background Initialization for Video Surveillance

  • Lim Kang Mo;Lee Se Yeun;Shin Chang Hoon;Kim Yoon Ho;Lee Joo Shin
    • Proceedings of the IEEK Conference
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    • 2004.08c
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    • pp.810-813
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    • 2004
  • In this paper, a background initialization for video surveillance proposed. The proposed algorithm is that the background images are sampled n frames during ${\Delta}t$ All Sampling frames are divided by $M{\times}N$ size block every frame. Average values of pixels for same location block of the sampling frames during ${\Delta}t$t are taken. then the maximum intensity $\alpha$ and the minimun intensity $\beta$ is obtained, respecticely. The intial by $M{\times}N$ size block, then average intensity $\eta$ of pixels for the block is obtained. If the average intensity $\eta$ is out of the initial range of the background image, it is decided the moving object image, and if the average intensity $\eta$ is included in the initial range of the background image. it is decided the background image. To examine the propriety of the proposed algorithm in this paper, the accuracy and robustness evaluation results for human and car in the indoor and outdoor enviroment. the error rate of the proposed method is less than the existing methods and the extraction rate of the proposed method is better than the existing methods.

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THE SLOPE OF ΔM LIGHT CURVE DEPENDING UPON THE ITS LOCATION IN CCD FRAME (CCD 이미지 상의 그 위치와 ΔM 광도곡선의 기울기)

  • 정장해;임인성
    • Journal of Astronomy and Space Sciences
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    • v.19 no.1
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    • pp.39-46
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    • 2002
  • BV observations for V523 Cas were performed with 1.8m telescope and 2K CCD camera at Bohyunsan Optical Astronomy Observatory, Korea, on October 27, 1999. ${\Delta}m$ light curves for 11 comparison objects were made. It was found that their light curve slopes are different each other. Factor analysis for items of slope, (b-v) , magnitude, X pixel, and Y pixel results that there is strong correlation between the slope and the location (X,Y). It might be due to problems of CCD cooling system.