• The Plant Pathology Journal
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• v.39 no.1
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• pp.39-51
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• 2023

Common bean (Phaseolus vulgaris L.) is one of the most important crops in human food production. The occurrence of diseases, such as white mold, caused by Sclerotinia sclerotiorum can limit the production of this legume. The use of Trichoderma has become an important strategy in the suppression of this disease. The aim of the present study was to evaluate the effect of volatile organic compounds (VOCs) emitted by Trichoderma azevedoi CEN1241 in five different growth periods on the severity of white mold in common bean. The in vitro assays were carried out in double-plate and split-plate, and the in vivo assays, through the exposure of the mycelia of S. sclerotiorum to the VOCs of T. azevedoi CEN1241 and subsequent inoculation in bean plants. Chemical analysis by gas chromatography coupled to mass spectrometry detected 37 VOCs produced by T. azevedoi CEN1241, covering six major chemical classes. The profile of VOCs produced by T. azevedoi CEN1241 varied according to colony age and was shown to be related to the ability of the biocontrol agent to suppress S. sclerotiorum. T. azevedoi CEN1241 VOCs reduced the size of S. sclerotiorum lesions on bean fragments in vitro and reduced disease severity in a greenhouse. This study demonstrated in a more applied way that the mechanism of antibiosis through the production of volatile compounds exerted by Trichoderma can complement other mechanisms, such as parasitism and competition, thus contributing to a better efficiency in the control of white mold in bean plants.

• Journal of the Microelectronics and Packaging Society
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• v.28 no.1
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• pp.39-46
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• 2021

The quantitative measurement of interfacial adhesion energy (Gc) of multilayer thin films for Cu interconnects was investigated using a double cantilever beam (DCB) and 4-point bending (4-PB) test. In the case of a sample with Ta diffusion barrier applied, all Gc values measured by the DCB and 4-PB tests were higher than 5 J/㎡, which is the minimum criterion for Cu/low-k integration without delamination. However, in the case of the Ta/Cu sample, measured Gc value of the DCB test was lower than 5 J/㎡. All Gc values measured by the 4-PB test were higher than those of the DCB test. Measured Gc values increase with increasing phase angle, that is, 4-PB test higher than DCB test due to increasing plastic energy dissipation and roughness-related shielding effects, which matches well interfacial fracture mechanics theory. As a result of the 4-PB test, Ta/Cu and Cu/Ta interfaces measured Gc values were higher than 5 J/㎡, suggesting that Ta is considered to be applicable as a diffusion barrier and a capping layer for Cu interconnects. The 4-PB test method is recommended for quantitative adhesion energy measurement of the Cu interconnect interface because the thermal stress due to the difference in coefficient of thermal expansion and the delamination due to chemical mechanical polishing have a large effect of the mixing mode including shear stress.

• Journal of the Korean Geographical Society
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• v.30 no.2
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• pp.132-145
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• 1995

The Purpose of this study is to integrate two opposite paradigms, (development from above) and (development from below), by means of A. Giddenss (structuration theory) and to provide practical development strategies on the basis of integrated paradigm. The integration of these two opposite paradigms is in fact the internalization of epistemological overcoming of 'dependency', which means the structural transformation of dualistic thinking into monistic thinking that the enlargement of capitalist world-system can be 'development' and it may also be 'dependency'. Therefore the practical main issue of this integrated paradigm results in how peripheral countries should achieve self-reliant and continuous development under the circumstances of dependency. To achieve such development while resisting the growing arrogance of transnational capital, development strategies should be prepared to maker revitalized political community designed to fit a human scale and for the economy to be subordinated to the political will of the community. And at the same time the 'empowerment' of people should be strengthened.

• Smart Structures and Systems
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• v.3 no.3
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• pp.281-298
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• 2007

The load carrying capacity of a bridge needs to be properly assessed to operate the bridge safely and maintain it efficiently. For the evaluation of load carrying capacity considering the current state of a bridge, static and quasi-static loading tests with weight-controlled heavy trucks have been conventionally utilized. In these tests, the deflection (or strain) of the structural members loaded by the controlled vehicles are measured and analyzed. Using the measured data, deflection (or strain) correction factor and impact correction factor are calculated. These correction factors are used in the enhancement of the load carrying capacity of a bridge, reflecting the real state of a bridge. However, full or partial control of the traffic during the tests and difficulties during the installment of displacement transducers or strain gauges may cause not only inconvenience to the traffic but also the increase of the logistics cost and time. To overcome these difficulties, an alternative method is proposed using an excited response part of full measured ambient acceleration data by ordinary traffic on a bridge without traffic control. Based on the modal properties extracted from the ambient vibration data, the initial finite element (FE) model of a bridge can be updated to represent the current real state of a bridge. Using the updated FE model, the deflection of a bridge akin to the real value can be easily obtained without measuring the real deflection. Impact factors are obtained from pseudo-deflection, which is obtained by double-integration of the acceleration data with removal of the linear components on the acceleration data. For validation, a series of tests were carried out on a steel plategirder bridge of an expressway in Korea in four different seasons, and the evaluated load carrying capacities of the bridge by the proposed method are compared with the result obtained by the conventional load test method.

• Korean journal of applied entomology
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• v.31 no.3
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• pp.205-240
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• 1992

In reality, it is a green revolution of the entire agricultural matrix in Korea that integrated pest control plays an important role in the possible breakthrough in rice self-sufficiency. In paddy agroecosystem as man-modified environment, rice is newly established every year by transplantation under diverse water regimes which affect a microclimate. Standing water benefits rice by regulating the microclimate, but it favors the multiplication of certain pets through the amelioration of the microclimate. Further, the introduction of high yielding varieties with the changing of cultural practices results in changing occurrence pattern of certain pests. In general, japonica type varieties lack genes resistant to most of the important pests and insect-borne virus diseases, whereas indica type possesses more genes conferring varietal resistance. Thus, this differences among indica type, form the background of different approaches to pest management. The changes in rice cultivation such as double cropping, growing high-yielding varieties requiring heavy fertilization, earlier transplanting, intensvie-spacing transplanting, and intensive pesticide use as a consequence of the adoption of improves rice production technology, have intensified the pest problems rather than reduced them. The cultivation of resistant varieties are highly effective to the pest, their long term stability is threathened because of the development of new biotypes which can detroy these varieties. So far, three biotypes of N. lugens are reported in Korea. Since each resistant variety is expected to maintain several years the sequential release of another new variety with a different gene at intervals is practised as a gene rotation program. Another approach, breeding multilines that have more than two genes for resistance in a variety are successfully demonstrated. The average annual rice losses during the last 15 years of 1977-’91 are 9.3% due to insect pests without chemical control undertaken, wehreas there is a average 2.4% despite farmers’insecticide application at the same period. In other words, the average annual losses are prvented by 6.9% when chemical control is properly employed. However, the continuous use of a same group of insecticides is followed by the development of pest resistance. Resistant development of C. suppressalis, L. striatellus and N. cincticeps is observed to organophosphorous insecticides by the mid-1960s, and to carbamates by the early 1970s in various parts of the country. Thus, it is apparent that a scheduled chemical control for rice production systems becomes uneconomical and that a reduction in energy input without impairing the rice yield, is necessarily improved through the implementation of integrated pest management systems. Nationwide pest forecasting system conducted by the government organization is a unique network of investigation for purpose of making pest control timely in terms of economic thresholds. A wise plant protection is expected to establish pest management systems in appropriate integration of resistant varieties, biological agents, cultural practices and other measures in harmony with minimizing use of chemical applications as a last weapon relying on economic thresholds.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.9
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• pp.979-986
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• 2010

This paper presents an algorithm for retrieving precise radar cross sections(RCS) of various trihedral corner reflectors (TCR) which are external calibrators of synthetic aperture radar(SAR) systems. The theoretical RCSs of the TCRs are computed based on the physical optics(PO), geometrical optics(GO), and physical theory of diffraction(PTD) techniques; that is, the RCS computation includes the single reflections(PO), double reflections(GO-PO), triple reflections(GO-GO-PO), and edge diffractions(PTD) from the TCR. At first, we acquire an SAR image of the area that five TCRs installed in, and then extract the RCS of the TCRs. The RCSs of the TCRs are extracted accurately from the SAR image by adding up the power spill, which is generated due to the radar IRF(Impulse Response Function), using a square window. We compare the extracted RCSs with the theoretical RCSs and analyze the difference between the theoretical and experimental RCSs of the TCR for various window sizes and various backscattering coefficient levels of the adjacent area. Finally, we propose the minimum size of the integration area and the maximum level of the backscattering coefficients for the adjacent area.

• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.450-457
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• 1998

The cryparin of Cryphonectria parasitica belongs to a cell wall associated fungal hydrophobin. The cryparin, though it is encoded by a single copy gene, is known for the high expression during the liquid culture of C. parasitica, and it turns out that 22% of total mRNA was transcribed for cryparin at 48hr after the liquid culture. In addition, it is also known as one of down-regulated fungal proteins by the presence of double stranded RNA virus, Cryphonectria hypovirus 1. In previous studies (Kim et al., 1999), we have constructed a cryparin-null mutant by replacing the cryparin gene with hygromycin B resistance gene due to site directed homologous recombination. In order for the promoter analysis of cryparin which seems to be very strong as well as mycoviral specific, it is preferable to have a strain with only a target promoter replaced and a discernable target site for incoming vectors. However, the cryparin-null mutant revealed the presence of an additional copy of transforming vector except the one which replaced the cryparin gene. In addition, the cryparin-null mutant did not contain any markers for targeted integration of incoming vectors. This prompts us to design an experiment to obtain a strain for promoter analysis of cryparin gene. A different mating type strain EP6(Mata, $met^-$) was mated with the cryparin-null mutant ${\triangle}$Crp194-7(MatA, Crp${\triangle}$::hph) to make the progenies with only a single replacement vector and $met^-$ characteristic remained. Nutritional assay as well as Southern blot analysis revealed that the progeny, ${\triangle}$Crp194-a6, was the methionine auxotroph with a single replacing vector in genome. Northern blot analysis and PAGE showed that there was no cryparin produced in this bred strain either.

• KSBB Journal
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• v.11 no.1
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• pp.8-14
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• 1996

Bacillus subtillis strains with transition state regulator mutations and a spore mutation were developed for the overexpression of apsE and for the enhancement of expression level. Among the many regulator genes, degU and hpr were chosen as a representative positive and negative regulator for the aprE, respectively. Spo II G was used for the construction of asporogeneous strains. All the mutants were constructed from two protease-deleted strain DB104 and the apsE gene was transformed with an integration vector pMK101. DB104(deg$U^h$(32) $his^+$)::pMK101(Cm) and DB104($\Delta$her(Em))::pMKl01(Cm) show 7-fold and about 2-fold increase in aprE expression level, respectively. But the effect of transition state regulator mutation on the aprE expression was diminished when the integrated aprE gene was amplified by the high concentration of chloramphenicol, i. e. 30 $\mu\textrm{g}$/ml. DB104($\Delta$spoIIG(Pm) degUh(32) his+)::pMK101(Cm) and DB104($\Delta$spoIIG(Pm) $\Delta$hpr(Em))::pMK101 double mutant show 10-fold and 3-fold increase in aprE expression level, respectively. The results suggest that sporulation mutation and transition state regulator mutation have independent and additive effect on the aprE expression, and the same gene dosage effect on the transition state regulator mutation was also identified.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.614-621
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• 2019

A generalized laminated composite beam element is presented for the flexural and buckling analysis of laminated composite beams with double and single symmetric cross-sections. Based on shear-deformable beam theory, the present beam model accounts for transverse shear and warping deformations, as well as all coupling terms caused by material anisotropy. The plane stress and plane strain assumptions were used along with the cross-sectional stiffness coefficients obtained from the analytical technique for different cross-sections. Two types of one-dimensional beam elements with seven degrees-of-freedom per node, including warping deformation, i.e., three-node and four-node elements, are proposed to predict the flexural behavior of symmetric or anti-symmetric laminated beams. To alleviate the shear-locking problem, a reduced integration scheme was employed in this study. The buckling load of laminated composite beams under axial compression was then calculated using the derived geometric block stiffness. To demonstrate the accuracy and efficiency of the proposed beam elements, the results based on three-node beam element were compared with those of other researchers and ABAQUS finite elements. The effects of coupling and shear deformation, support conditions, load forms, span-to-height ratio, lamination architecture on the flexural response, and buckling load of composite beams were investigated. The convergence of two different beam elements was also performed.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.606-611
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• 1999

To identify irradiated foods, studies have been carried out with electron spin resonance (ESR) spectroscopy on bone containing foods, such as chicken, pork, and beef. Bones cleaned, pieced and dried were irradiated with doses of 0, 1, 3, 5 kGys using a $Co^{60}$ irradiator. The bones were placed in a resonant quartz tube with an internal diameter of about 4.0 mm within the Bruker Win-ESR spectrometer, and the intensity of the ESR signal could be quantified by double integration of the first derivative spectrum. The irradiated bone presented an asymmetric absorption in shape, different from that of an unirradiated one. It could be possible to detect at doses lower than 1 kGy below the dose employed commercially (3 kGy) in the case of irradiated chicken bone. The signal intensity was greatest in the beef bone, intermediate in the pork bone and lowest in the chicken bone; it was normally lower for smaller animals than for larger species, and small variations were observed between samples of the same species. The intensity of the signal induced in bones increased linearly with irradiation doses in the range of 1.0 kGy to 5.0 kGy, and it was possible to distinguish between samples given low and high doses of irradiation. The signal stability for 6 weeks made them ideal for the quick and easy identification of irradiated meats.