• Applied Biological Chemistry
• /
• v.31 no.3
• /
• pp.219-225
• /
• 1988

Reverse transcriptase gene of Avian sarcoma virus(ASV) was cloned with a thermoinducible expression vector, pPL-lambda. E. coli N4830 which carries temperature sensitive cI857 la mbda repressor, was transformed with this pPL-pol plasmid DNA. The RNA transcribed by those tranoformants was isolated and analyzed. It was shown that the inserted reverse transcriptase gene of ASV was transcribed at high-level when cells were grown at high temperature.

• Journal of the Korean Society for Precision Engineering
• /
• v.21 no.6
• /
• pp.188-196
• /
• 2004

The objective of this paper is to propose a new technology of the orthopaedic surgery using the combination of reverse engineering (RE) based on CT data and rapid prototyping (RP). The proposed technology utilizes symmetrical characteristics of the human body and capability of the combination of RE and RP, which rapidly manufactures three-dimensional parts from CT data. The original .stl data of injured extents are generated from the mirror transformation of .stl file fur uninjured extents. The physical shape before injuring is manufactured from RP using the original .stl data. Subsequently, pre-operative planning, such as a selection of proper implants, preforming of the implant, a decision of fixation locations and an insert position for the implant, an estimation of the invasive size, and pre-education of operators are performed using the physical shape. In order to examine the applicability and the efficiency of the proposed surgical technology, various case studies, such as a distal tibia commented fracture, a proximal tibia plateau fracture and an iliac wing fracture of pelvis, are carried out. From the results of case studies, it has been shown that the proposed technology is an effective surgical tool of the orthopaedic surgery reducing the operational time, the operational cost, the radiation exposure of the patient and operators, and morbidity. In addition, the proposed technology could improve the accuracy of operation and the speed of rehabilitation.

• Applied Chemistry for Engineering
• /
• v.32 no.6
• /
• pp.679-683
• /
• 2021

Lecithin, a zwitterionic phospholipid, forms spherical reverse micelles in nonpolar organic solvents such as decane. The addition of monovalent ions like lithium chloride (LiCl) to lecithin organosols induces the transformation of organosols into organogels due to the entanglement of reverse cylindrical micelles. In this study, we investigate the effect of pentanol acting as co-surfactant on rheological properties of lecithin/LiCl mixtures. From rheological studies, we find that the viscosity and elastic property of organogels decreased upon the addition of pentanol to organogels. The decrease in viscosity and elastic property can be attributed to the shortening of reverse cylindrical micelles confirmed by small angle X-ray scattering (SAXS).

• Journal of Electrical Engineering and Technology
• /
• v.12 no.2
• /
• pp.683-688
• /
• 2017

The unscented Kalman filter features a direct transforming process involving unscented transformation for removing the linearization process error that may occur in the extended Kalman filter. This paper proposes a reduced-order unscented Kalman filter for the sensorless control of a permanent magnet synchronous motor. The proposed method can reduce the computational load without degrading the accuracy compared to the conventional Kalman filters. Moreover, the proposed method can directly estimate the electrical rotor position and speed without a back-electromotive force. The proposed Kalman filter for the sensorless control of a permanent magnet synchronous motor is verified through the simulation and experimentation. The performance of the proposed method is evaluated over a wide range of operations, such as forward and reverse rotations in low and high speeds including the detuning parameters.

• Proceedings of the KSME Conference
• /
• 2004.11a
• /
• pp.720-724
• /
• 2004

This paper introduces a new type of driving mechanism for rescue robot that has a variable geometry single-track which satisfies the pre-conditions of rescue robot. This mechanism is a symmetric configuration that has dual directions and prepares against overturn. By using transformation, it can reduce the energy consumption in steering and rotating. And also it maximizes the ability to overcome obstacles, like steps. It is designed to make the size of robot compact and to have the low center of gravity in driving on steps. Finally, we optimized the design variables of components determining the shape of reverse-trapezoid frame to enhance the adaptability to 4 phases of climbing steps.

• Journal of the Korean Society of Tobacco Science
• /
• v.19 no.2
• /
• pp.117-123
• /
• 1997

Viral coat protein (CP) encoding cDNA with artificial start and stop codons was synthesized by reverse-transcriptase polymerase chain reaction (RT-PCR) from the Korean isolate of potato virus Y-vein nectrosis strain (pVY-VN). To make PVY CP cDNA to untranslatable form, three stop codons were inserted near the start codon by "megaprimer-PCR" method. The untranslatable CP cDNA was subcloned to plant expression vector and transferred to N. tabacum cv. NC82 by Agrobacterium-mediated transformation. Highly resistant plants to PVY infection were screened, based on symptom development after mechanical virus inoculation. By genomic PCR and Southern blot analysis, one or more copies of the untranslatable CP gene were found in all transformants. From northern blot analysis, highly resistant transgenic lines had very low level of CP transcript but susceptible lines had high level, suggesting resistance to PVY infection should be related to RNA-mediated mechanism.mechanism.

• Journal of the Korean Society for Precision Engineering
• /
• v.20 no.9
• /
• pp.197-204
• /
• 2003

This study proposes a method to reduce errors in scanning object and registration using a laser scanner. The method consists of 3 stages. First, there is an error induced by the difference of the distance between the probe and the object. It is possible to reduce the error by planning a scanning strategy: object setting, scan path. Second, the scan data of the tooling ball affects calculating the tooling ball center. A z-direction compensation is given to calculate more accurate registration points. Third, three points are used to determine a coordinate transformation on each frame. The maximum error usually lies on the third tooling ball in the conventional merging method. LSM (Least Square Method) is applied to a coordinate transformation to reduce the registration error.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.58 no.12
• /
• pp.2370-2378
• /
• 2009

The enhanced phase angle estimation algorithm is essential to supply the power stably under synchronizing with grid source. In this paper, we are proposed the novel phase angle estimation algorithm and verified the validity of proposed method as simulation with PSIM and experiments. We sort the harmonics element using high-pass filter(HPF) that have the cut-off frequency below basic element and make reverse d-q transformation. So, it can be restored the harmonics element at stationary axis, and we can get the fundamental voltage element of AC grid. Proposed PLL method have a rapid responsibility and a large margin at controller design than conventional method because it have a small phase delay and a sufficient controller gain margin. And, it can reduce the error of voltage rms value and axis transformation according to robust PLL algorithm against the harmonic and phase unbalance.

• KSBB Journal
• /
• v.8 no.2
• /
• pp.104-109
• /
• 1993

A vector for plant transformation which had two reporter genes(Gus and Hpt genes) in a single plasmid was constructed. After rice embryos imbibed DNA solution, DNA uptake and gene expression in rice were monitored. Main expression sites of the Gus gene were meristem of root and coleoptiles. There was no difference in Hpt gene expression between a single Hpt vector and the constructed vector in viability of rice in the hygromycin medium after DNA imbibition, The genomic DNA and total RNA extracted from rice transformant survived in the hygromycin medium were subjected to PCR and RT PCR analysis, respectively. As a result, we found the existence of the Hpt gene and its expression in rice.

• Journal of the Korean Society of Tobacco Science
• /
• v.25 no.1
• /
• pp.12-19
• /
• 2003

Transgenic tobacco plants were selected by using the transformation of putrescine N-methyltransferase(PMT) gene, the key enzyme in diverting polyamine metabolism towards the biosynthesis of nicotine. PMT was fused in reverse orientation to the CaMV 35S promoter of the plant expression vector pBTEX(pPAB3) to produce tobacco plants of low nicotine content. To compare nicotine content, only pBTEX vector and PMT gene which was fused in forward orientation to the CaMV 35S promoter(pPAB2) were also transformed to the leaf tobacco plants(Nicotiana tabacum cv. NC82 and N. tabacum cv. Br2l). The presence of sense- and antisense-PMT gene, and pBTEX vector in the transgenic plant was confirmed by genomic PCR.