• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.189-192
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• 2000

The objective of this study was to investigate the effect of high content of light-absorbing pigments on overall photosynthetic efficiency in high density microalgal cultures. The light harvesting complex II (LHC II) regulating gene of Rhodobacter sphaeroides, photosynthetic purple bacterium, was removed to construct a mutant strain that had less pigment content. The mutant and wild type strains were cultured under various light intensity by adjusting the distance from the light source. The productivity of the mutant strain was higher at high light intensity (over 118 ${\mu}E/m^2/s$) compared with one of the wild type , and was lower at low light intensity (34 ${\mu}E/m^2/s$). Especially, the concentration of LHC II mutant strain was 56% higher at 118 ${\mu}E/m^2/s$. The reduction of per cell pigment contents in the mutant strain lessened the degree of the mutual shading and thus enhanced the overall photosynthetic efficiency.

• Korean Journal of Microbiology
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• v.34 no.3
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• pp.115-119
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• 1998

We cloned the 4.8 kb BglII fragment containing genes downstream pHENX7 from Pseudomonas sp. strain DJ77. The restriction map of the resultant clone, recombinant plasmid pYCS500, was determined. Sequencing analysis of the 465 bp HindIII-ClaI fragment revealed an open reading frame of 282 bp that was then designated phnM. The deduced polypeptide is 93 amino acid residues long with a $M_r$ of 10,008. The PhnM has 37.3-53.9% identity with plant-type ferredoxin proteins such as NahT, XylT, DmpQ, AtdS, PhlG, PhhQ and TbuW and contains the motif similar to well-conserved functional domains of those proteins.

• Steel and Composite Structures
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• v.34 no.2
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• pp.279-288
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• 2020

The computational post-buckling strength of the tilted sandwich composite shell structure is evaluated in this article. The computational responses are obtained using a mathematical model derived using the higher-order type of polynomial kinematic in association with the through-thickness stretching effect. Also, the sandwich deformation behaviour of the flexible soft-core sandwich structural model is expressed mathematically with the help of a generic nonlinear strain theory i.e. Green-Lagrange type strain-displacement relations. Subsequently, the model includes all of the nonlinear strain terms to account the actual deformation and discretized via displacement type of finite element. Further, the computer code is prepared (MATLAB environment) using the derived higher-order formulation in association with the direct iterative technique for the computation of temperature carrying capacity of the soft-core sandwich within the post-buckled regime. Further, the nonlinear finite element model has been tested to show its accuracy by solving a few numerical experimentations as same as the published example including the consistency behaviour. Lastly, the derived model is utilized to find the temperature load-carrying capacity under the influences of variable factors affecting the soft-core type sandwich structural design in the small (finite) strain and large deformation regime including the effect of tilt angle.

• The Plant Pathology Journal
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• v.28 no.3
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• pp.295-298
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• 2012

Genetic diversity among Pseudomonas syringae pv. morsprunorum isolates from Prunus mume in Korea and Japan was investigated by comparative sequence analysis of the 16S rRNA gene. The strains included 24 field isolates recovered from P. mume in Korea along with seven Japanese strains. Two strains isolated from P. salicina in Japan, one strain from P. avium in the United Kingdom, and the pathotype strain were also used for comparison with their 16S rRNA gene sequences. Nearly complete 16S rRNA gene sequences were sequenced in all 35 strains, and three sequence types, designated types I, II and III, were identified. Eleven strains consisting of five Korean isolates, five Japanese strains, and one strain from the United Kingdom belonged to type I, whereas the pathotype strain and another 19 Korean isolates belonged to type III. Another four Japanese strains belonged to type II. Type I showed 98.9% sequence homology with type III. Type I and II had only two heterogeneous bases. The 16S rRNA sequence types were correlated with the races of P. syringae pv. morsprunorum. Type I and II strains belonged to race 1, whereas type III isolates were included in race 2. Sequence analyses of the 16S rRNA gene from P. syringae pv. morsprunorum were useful in identifying the races and can further be used for epidemiological surveillance of this pathogen.

• Journal of the Semiconductor & Display Technology
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• v.14 no.2
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• pp.23-27
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• 2015

In this paper, eco-friendly paper strain gauge was fabricated in the way of printing strain gauge on paper substrate, using PEDOT:PSS ink and inkjet printer technology. As a p-type conductive high polymer, PEDOT:PSS is known to be piezoresistive effect. I formed a strain gauge by connecting in parallel 5 lines of $60{\mu}m$ width printed with PEDOT:PSS. To minimize surrounding influence such as temperature, I formed wheat-stone bridge by combining 4 strain gauges (quarter-bridge strain gauge) which were made up of PEDOT:PSS 5 lines and measured. In quarter-bridge strain gauge, only two strain gauges, facing each other, arranged in strain and horizontal direction were deformed while the other two strain gauge of vertical direction were not. Therefore, quarter-bridge strain gauge showed the output of half bridge. The fabricated quarter-bridge strain gauge had output sensitivity of $105.6{\mu}V/V{\cdot}mm$ and its output linearity was relatively good.

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1392-1398
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• 2006

We investigated a possible coordination between the biosyntheses of two polyketides in the cereal head blight fungus Gibberella zeae, zearalenone (ZEA) and aurofusarin (AUR), which are catalyzed by the polyketide synthases (PKS) PKS4/PKS13 and PKS12, respectively. To determine if the production of one polyketide influences that of the other, we used four different transgenic strains of G zeae; three were deficient for either ZEA or AUR or both, and one was an AUR-overproducing strain. The mycelia of both the wild-type and ${\Delta}PKS4$ strain deficient for ZEA produced AUR normally, whereas the mycelia of both the ${\Delta}PKS12$ and ${\Delta}PKS4::{\Delta}PKS12$ strain showed no AUR accumulation. All the examined deletion strains caused necrotic spots on the surface of com kernels and were found to produce the nonpolyketide mycotoxins trichothecenes to the same amount as the wild-type strain. In contrast, the AUR-deficient ${\Delta}PKS12$ strains produced greater quantities of ZEA and its derivatives than the wild-type progenitor on both a rice substrate and a liquid medium; the AUR-overproducing strain did not produce ZEA on either medium. Furthermore, the expression of both PKS4 and PKS13 was induced earlier in the ${\Delta}PKS12$ strains than in the wild-type strain, and there was no difference in the transcription of PKS12 between the two strains. Therefore, these results indicate that the ZEA biosynthetic pathway is negatively regulated by the accumulation of another polyketide (AUR) in G zeae.

• Smart Structures and Systems
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• v.11 no.5
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• pp.477-496
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• 2013

Due to their cost-effectiveness and ease of installation, wireless smart sensors (WSS) have received considerable recent attention for structural health monitoring of civil infrastructure. Though various wireless smart sensor networks (WSSN) have been successfully implemented for full-scale structural health monitoring (SHM) applications, monitoring of low-level ambient strain still remains a challenging problem for WSS due to A/D converter (ADC) resolution, inherent circuit noise, and the need for automatic operation. In this paper, the design and validation of high-precision strain sensor board for the Imote2 WSS platform and its application to SHM of a cable-stayed bridge are presented. By accurate and automated balancing of the Wheatstone bridge, signal amplification of up to 2507-times can be obtained, while keeping signal mean close to the center of the ADC span, which allows utilization of the full span of the ADC. For better applicability to SHM for real-world structures, temperature compensation and shunt calibration are also implemented. Moreover, the sensor board has been designed to accommodate a friction-type magnet strain sensor, in addition to traditional foil-type strain gages, facilitating fast and easy deployment. The wireless strain sensor board performance is verified through both laboratory-scale tests and deployment on a full-scale cable-stayed bridge.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.586-591
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• 2001

In the cold forging, elastic deformation of the die has been investigated to improve the accuracy of cold forged parts with F.E.M analysis using DEFORM, and with experiments using strain gauges. In the experiments, initial billet was selected to easily find the effect of elastic deformation according to the forging modes, extrusion and upsetting type, and only extrusion type. Elastic deformation of the die can be obtained by the signal from the strain gauges and this signal can be amplified by data acquisition system during the process. In the F.E.M analysis, two types of analysis are used to predict elastic strain of the die. To improve an accuracy of forged product and die dimension, this study compared with strain distribution between experiment and F.E.M analysis. As a result, the history of the deformation of the die and elastic recovery of forged product can be obtained by the elastic strain analysis of forged product and die according to the forging modes.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.05a
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• pp.150-153
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• 2001

In this paper, the tensile test of three kinds of the specimens was performed. Type I specimen is without notch and type II, III specimens have a radius of semi-circular edge crack of 2.5mm, 4.0mm. The tensile load(20kN and 30kN) was applied to the specimen by Universal Testing Machine. 3D-ESPI system and strain gauge measured simultaneously the strain in the center of the specimen and near the edge crack. The test results were compared with each other. Moreover, the stress concentration factor based on geometric information was calculated to confirm the accuracy of the strain measured by 3D-ESPI system. The calculated strain was compared with the measured one by 3D-ESPI system. As a result, it was confirmed that 3D-ESPI system measured the right strain near the semi-circular edge crack of the specimens.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.384-390
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• 2021

A Gram-negative, aerobic, motile by gliding, and rod-shaped marine bacterium, designated CE67^T was isolated from the marine sponge Callyspongia elegans on Biyang-do in Jeju Island. The CE67^T strain grew optimally at 25℃, pH 7.5, and in the presence of 2-3% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain CE67^T was related to the genus Aureivirga and had the highest 16S rRNA gene sequence similarity to the Aureivirga marina VIII.04^T type strain (96.3%). The primary fatty acids (>10%) of strain CE67^T were iso-C_15:0 (35.3%) and iso-C_17:0 3OH (21.8%). The polar lipid profile of strain CE67^T contained phosphatidylethanolamine, unidentified aminolipids, and unidentified lipids. The predominant menaquinone was MK-6. The DNA G+C content was 29.1 mol%. Based on the polyphasic taxonomic analysis, strain CE67^T was determined to be a representative novel species of the genus Aureivirga for which we propose the name Aureivirga callyspongiae sp. nov., whose strain type is CE67^T (=KCTC 42847^T=JCM 34566^T).