• Advances in concrete construction
• /
• v.11 no.1
• /
• pp.59-71
• /
• 2021

This research aims to study the utilization of olive waste ash (OWA) in the production of concrete as a partial substitute for cement. Effects of using OWA on the physical and mechanical properties of concrete mixtures have been investigated. This is done by carrying out tests involving the addition of various percentages of OWA to cement (0%, 5%, 10% and 15%). For each percentage, tests were performed on both fresh and hardened concrete; these included slump test, unit weight test and compressive strength test after 7, 28 and 90 days. Durability tests were investigated in solutions containing 5% NaOH and MgSO4 by weight of water. In addition, resistance to high temperatures was tested by subjecting the cubes to high temperatures of up to 170℃. The results of this research indicate that a higher percentage of OWA gives a lower compressive strength and lower workability but higher performance in terms of durability against both different weather conditions and high temperatures.

• Transactions of Materials Processing
• /
• v.19 no.1
• /
• pp.38-43
• /
• 2010

Electromagnetic forming (EMF) method is one of high-velocity forming processes, which uses electromagnetic Lorentz force. Advantages of this forming technique are summarized as improvement of formability, reduction in wrinkling, non-contact forming and applications of various forming process. In this study, the EMF apparatus is developed. It is designed to be stored in 10 capacitors connected in parallel, each with a capacitance of $50{\mu}F$ and maximum working voltage of 5kV. The system has capacitance of $500{\mu}F$ and maximum stored energy of 6.25kJ. And EMF experiments are carried out to verify the feasibility of the EMF apparatus, which has enough forming force from the results of EMF experiment. In addition, peak current carrying a forming coil is predicted from theoretical background, and verified the predicted value compared with experimental value using the current measurement equipment. Consequently, EMF apparatus developed in this study can be applied to various EMF researches for commercialization.

• International Journal of Automotive Technology
• /
• v.1 no.1
• /
• pp.56-60
• /
• 2000

The customers demand of a good vehicle agility consists of a quick reaction of the vehicle with the actuation of the throttle pedal on one hand and a high comfort level of vibration and noise within the vehicle on the other hand, which means the reduction of disturbing side effects. In order to achieve a satisfactory compromise it is necessary to gain a deeper understanding of the complex, high dynamic vibrations system "vehicle / drive train". For several years the ika has been carrying out such detailed vehicle investigations and test bench measurements in addition to comprehensive CAE analysis for various research projects in partnership with different vehicle manufacturers.

• Journal of Microbiology
• /
• v.35 no.2
• /
• pp.123-126
• /
• 1997

The aim of the present study was to optimize culture condition for the expression of lipocortin-1$_{1-185}$ in a recombinant of Escherichia coli using batch system. Plasmid (pHT22) carrying lipocortin-1$_{1-185}$ gene was well maintained in the recombinant with the addition of amplicillin as a selection pressures. Optimum temperature was 28$^{\circ}C$ for seed culture and 4$0^{\circ}C$ for main culture and the optimum pH was 7.0. The production of Lipocortin-1$_{1-185}$ was closely associated with cell growth and related to plasmid amplification.

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2002.10a
• /
• pp.179-182
• /
• 2002

Rapid Prototyping (RP) technologies provide the ability to fabricate initial prototypes from various model materials. Stratasys' Fused Deposition Modeling (FDM) is a typical RP process that can fabricate prototypes out of plastic materials, and the parts made from FDM were often used as load-carrying elements. Because FDM deposits materials in about $300\mutextrm{m}$ thin filament with designated orientation, parts made from FDM show anisotropic material properties. This paper proposes an analytic model to predict the tensile strength of FDM parts. Applying the Classical Lamination Theory, which was developed for laminated composite materials, a computer code was implemented. Tsai-Wu failure criterion was added to the code to predict the failure of the FDM parts. The tensile strengths predicted by the analytic model were compared with experimental data. The data and prediction agreed reasonably well to prove the validity of the model. In addition, a web-based advisory service was developed to provide to strength prediction and design rules for FDM parts.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.04a
• /
• pp.20-24
• /
• 1997

In general, pantograph type manipulators are used for carrying heavy payloads with positional accuracy. In this paper, a double pantograph type manipulator, activated by two slider joints, is studied for applying to file handing machine in atomic power plant. In order to realize the stable horizontal movement of a heavy fuel rod whit good positional accuracy, methods for allocating slider and finding constant joint rates are proposed. In addition, the static deflection of the proposed mechanism was studied using transfer-stiffness matrix method. A neural network control algorithm which compensates static deflections is explored with computer simulations.

• Journal of Plant Biology
• /
• v.32 no.2
• /
• pp.67-78
• /
• 1989

Hybridization of DNA isolated from leaves of Russet Burbank potato with tomato cDNA as a probe revealed the presence of about ten inhibitor 1 genes in the genome. Screening of a genomic library of Russet Burbank potato resulted in isolation of seven different genomic clones carrying inhibitor I genes. One of the genomic clones, clone 2, contained two EcoRI fragments of 3.4 and 1.8 kb in size, respectively, which were hybridized with the probe. The nucleotide sequence of parts of the hybridizing EcoRI fragments revealed that they contain a complete gene which codes for an open reading frame of 107 amino acids. It is interrupted by two intervening sequences of 502 and 493 bp, situated at the positions of codons 17 and 43, respectively, of the open reading frame. Putative regulatory sequences, TATAAA and CCACT, were found at the 5' flanking region. In addition, a copy of a 100 bp repeat found at a tomato inhibitor I gene was identified.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2005.11a
• /
• pp.95-105
• /
• 2005

Transposon-mediated insertional mutagenesis provides one of the most powerful tools for functional studies of genes in higher plants. This project has been performed to develop a large population of insertional mutations, and to construct databases of molecular information on Ds insertion sites in rice. Ultimate goals are to supply genetic materials and information to analyze gene function and to identify and utilize agronomically important genes for breeding purpose. Two strategies have been employed to generate the large scale of transposon population in a Japonica type rice, Dongjin Byeo; 1) genetic crosses between Ac and Ds lines and 2) plant regeneration from seeds carrying Ac and Ds. Our study showed that over 70% of regenerated plants generally carried independent Ds elements and high activity of transposition was detected only during regeneration period. Ds-flanking DNA amplified from leaf tissues of F2 and T1 (or T2) plants have been amplified via TAIL-PCR and directly sequenced. So far, over 65,000 Ds lines have been generated and over 9,500 Ds loci have been mapped on chromosomes by sequence analysis. Database of molecular information on Ds insertion sites has been constructed, and has been opened to the public and will be updated soon at http://www.niab.go.kr. Detailed functional analysis of more than 30 rice mutants has been performed. Several Ds-tagged rice genes that have been selected for functional analysis will be briefly introduced. We expect that a great deal of information and genetic resources of Ds lines would be obtained during the course of this project, which will be shared with domestic and international rice researchers. In addition to the Japonica rice, we have established the tagging system in an rice line of indica genetic background, MGRI079. MGRI079 (Indica/Japonica) was transformed with Agrobacteria carrying Ac and Ds T-DNA vectors. Among transgenic lines, we successfully identified single-copy Ds and Ac lines in MGR1079. These lines were served as ‘starter lines’ to mutagenize Indica genetic background. To achieve rapid, large scale generation of Ds transposant lines, MGR1079 transformants carrying homozygous Ac were crossed with ones with homozygous Ds, and $F_2$seeds were used for plant regeneration. In this year, over 2,000 regeneration plants were grown in the field. We are able to evaluate the tagging efficiency in the Indica genetic background in the fall.

• Journal of Sericultural and Entomological Science
• /
• v.40 no.1
• /
• pp.52-59
• /
• 1998

For the construction of plasmid and bmNPV sarrying the FRT recognition site for the FLP recombinases, we synthesized the wild type FRT dligonucleotides. The target FRT sequences consist of three 13bp repeated DNA sequences; two repeats in a direct orientation and one inverted relative to the other two. In addition, there is an 8bp spacer region between the repeats which determune the orientation of the FRT recombination site. In order to place the FRT site both in target BmNPV genome and the transfer vector, we constructed a plasmid, FRT site both in the target BmNPv genome and the transfer vector, we constructed a plasmid, pFRT$\beta$-gal, carrying the FRT sites within the cloning sites of pSV vector and a recombinant BmNPV, vFRTPH, carrying the FRT sites at a downstream of polyhedrin promotor, respectively. In order to test the functionality of the FLP/FRT site-specific recombination system, vFRTPH, pFRT$\beta$-gal and pHsFLP DNA were co-transfected into BmN-4 cells. The resulting recombinant virus was designated a vFRT$\beta$2-gal. From construction analysis of the vFRT$\beta$2-gal with PCR technique it was concluded that the entire pFRT$\beta$-gal plasmid with $\beta$-galactosidase gene and origines of replication flanked by two functional hybrid FRT sequences. The efficiency of recombination was 8.7%, which was higher than that(2.2%) of recombination between a conventional transfer vector and the wild type BmNPV.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.44 no.3
• /
• pp.92-100
• /
• 2002

The advent or high-strength steel has enabled the arch structures to be relatively light, durable and long-spanned by reducing the cross sectional area. On the other hand, the possibility of collapse may be increased due to the slender members which may cause the stability problems. The limit analysis to estimate the ultimate load is based on the concept of collapse mechanism that forms the plastic zone through the full transverse sections. So, it is not appropriate to apply it directly to the instability analysis of arch structures that are composed with compressive members. The objective of this study is to evaluate the ultimate load carrying capacity of the parabolic arch by using the elasto-plastic finite element model. As the rise to span ratio (h/L) varies from 0.0 to 0.5 with the increment of 0.05, the ultimate load has been calculated fur arch structures subjected to uniformly distributed vertical loads. Also, the disco-elasto-plastic analysis has been carried out to find the duration time until the behavior of arch begins to show the stable state when the estimated ultimate load is applied. It may be noted that the maximum ultimate lead of the parabolic arch occurs at h/L=0.2, and the appropriate ratio can be recommended between 0.2 and 0.3. Moreover, it is shown that the circular arch may be more suitable when the h/L ratio is less than 0.2, however, the parabolic arch can be suggested when the h/L ratio is greater than 0.3. The ultimate load carrying capacity of parabolic arch can be estimated by the well-known formula of kEI/L$^3$where the values of k have been reported in this study. In addition, there is no general tendency to obtain the duration time of arch structures subjected to the ultimate load in order to reach the steady state. Merely, it is observed that the duration time is the shortest when the h/L ratio is 0.1, and the longest when the h/L ratio is 0.2.