• The Plant Pathology Journal
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• v.38 no.5
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• pp.425-431
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• 2022

Plant microbiota has influenced plant growth and physiology significantly. Plant and plant-associated microbes have flexible interactions that respond to changes in environmental conditions. These interactions can be adjusted to suit the requirements of the microbial community or the host physiology. In addition, it can be modified to suit microbiota structure or fixed by the host condition. However, no technology is realized yet to control mechanically manipulated plant microbiota structure. Here, we review step-by-step plant-associated microbial partnership from plant growth-promoting rhizobacteria to the microbiota structural modulation. Glutamic acid enriched the population of Streptomyces, a specific taxon in anthosphere microbiota community. Additionally, the population density of the microbes in the rhizosphere was also a positive response to glutamic acid treatment. Although many types of research are conducted on the structural revealing of plant microbiota, these concepts need to be further understood as to how the plant microbiota clusters are controlled or modulated at the community level. This review suggests that the intrinsic level of glutamic acid in planta is associated with the microbiota composition that the external supply of the biostimulant can modulate.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.4
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• pp.163-169
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• 1993

A flexible manipulator can move in the high speed even with the small driving torque. The dymanic equations of flexible manipulator which include 2 vibrational modes are derived using the clamped-free boundary condition. Simulation results of the 6th order model are well matched with experimental results. The hub angle of the flexible mainpulator can be controlled without vibration of the beam by the feedback of both hub angle and strain. The overshoot of the hub angle in the step response is reduced without sacrificing the rise time using the cycloidal function instead of the step function as the referenmce input.

• Knowledge Management Research
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• v.19 no.2
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• pp.151-162
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• 2018

Response surface methodology (RSM) is one of popular tools to support a systematic improvement of quality of design in the product and process development stages. It consists of statistical modeling and optimization tools. RSM can be viewed as a knowledge management tool in that it systemizes knowledge about a manufacturing process through a big data analysis on products and processes. The conventional RSM aims to optimize the mean of a response, whereas dual-response surface optimization (DRSO), a special case of RSM, considers not only the mean of a response but also its variability or standard deviation for optimization. Recently, a posterior preference articulation approach receives attention in the DRSO literature. The posterior approach first seeks all (or most) of the nondominated solutions with no articulation of a decision maker (DM)'s preference. The DM then selects the best one from the set of nondominated solutions a posteriori. This method has a strength that the DM can understand the trade-off between the mean and standard deviation well by looking around the nondominated solutions. A posterior method has been proposed for DRSO. It employs an interval selection strategy for the selection step. This strategy has a limitation increasing inefficiency and complexity due to too many iterations when handling a great number (e.g., thousands ~ tens of thousands) of nondominated solutions. In this paper, a TOPSIS-based method is proposed to support a simple and efficient selection of the most preferred solution. The proposed method is illustrated through a typical DRSO problem and compared with the existing posterior method.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.71-80
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• 2013

According to design specifications for structural safety, a bridge in initial design step has been modelled to have larger self-weight, external loads and less stiffness than those of real one in service. Thereby measured buffeting responses of existing bridge show different distributions from those of the design model in design step. In order to obtain accurate buffeting responses of the in-site bridge, the analysis model needs to be modified by considering the measured natural frequencies. Until now, a Manual Tuning Method (MTM) has been widely used to obtain the Measurement-based Model(MBM) that has equal natural frequencies to the real bridge. However, since state variables can be selected randomly and its result is not apt to converge exact rapidly, MTM takes a lot of effort and elapsed time. This study presents Buffeting Response Correction Method (BRCM) to obtain more exact buffeting response above MTM. The BRCM is based on the idea the commonly used frequency domain buffeting analysis does not need all structural properties except mode shapes, natural frequencies and damping ratio. BRCM is used to improve each modal buffeting responses of the design model by substituting measured natural frequencies. The measured natural frequencies are determined from acceleration time-history in ordinary vibration of the real bridge. As illustrated examples, simple beam is applied to compare the results of BRCM with those of a assumed MBM by numerical simulation. Buffeting responses of BRCM are shown to be appropriate for those of in-site bridge and the difference is less than 3% between the responses of BRCM and MTM. Therefore, BRCM can calculate easily and conveniently the buffeting responses and improve effectively maintenance and management of in-site bridge than MTM.

• Geophysics and Geophysical Exploration
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• v.20 no.3
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• pp.176-184
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• 2017

To interpret the seismic image precisely, random noises should be suppressed and the continuity of the image should be enhanced by using the appropriate smoothing techniques. Structure-Oriented Filter-Edge Preserving (SOF-EP) technique is one of the methods, that have been actively researched and used until now, to efficiently smooth seismic data while preserving the continuity of signal. This technique is based on the principle that diffusion occurs from large amplitude to small one. In a continuous structure such as a horizontal layer, diffusion or smoothing is operated along the layer, thereby increasing the continuity of layers and eliminating random noise. In addition, diffusion or smoothing across boundaries at discontinuous structures such as faults can be avoided by employing the continuity decision factor. Accordingly, the precision of the smoothing technique can be improved. However, in the case of the structure-oriented semblance technique, which has been used to calculate the continuity factor, it takes lots of time depending on the size of the filter and data. In this study, we first implemented the SOF-EP method and confirmed its effectiveness by applying it step by step to the field data. Next, we proposed and applied the corner response method which can efficiently calculate the continuity decision factor instead of structure-oriented semblance. As a result, we could confirm that the computation time can be reduced by about 6,000 times or more by applying the corner response method.

• Convergence Security Journal
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• v.14 no.3_2
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• pp.99-109
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• 2014

Disaster is when, where, and how uncertainties, which might occur. Thus, for disaster response and management at the national and local governments have been made. Korea has established the Disaster and Safety Management Basic Act. Disaster Management has been made at the national level which is to prevent disasters and countries in order to protect citizens from harm and dangerous. Korean Disaster management system is well equipped with advanced countries. The Organization of national and local government are well-maintained substantially for the disaster activities and step-by-step manuals activities. Despite that uncertainty, due to the nature of the disaster, while infrequent, causing large-scale tragedy. Minimize the damage of the disaster as a disaster management efforts are needed. Normally a real disaster, a disaster situation, efforts are to be utilized efficiently, the effectiveness of the system will appear. But while the number of large-scale disasters, including the sinking of Sewol this time for the government and local governments see the response process, the system did not work and the manual existed in the cabinet. There was no Prevention and preparation activities, there was no integrated organization for the response management with expertise in the professional staff. Whenever a large disaster raised repeatedly as a problem, but there was a substantial change in formal but no improvement. It will not reduce the damage if the disaster management is not prepared for a revolutionary turning point.

• Journal of The Korean Association For Science Education
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• v.25 no.3
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• pp.400-410
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• 2005

According to the cognitive conflict process model, student anxiety factor is known to have both positive and negative effects on student response behaviors in a conflict situation for conceptual change learning. However, there is little research that reveals what type of anxiety, either constructive or destructive, is related when conducting step-by-step experiments to resolve cognitive conflicts. This study attempted to learn the characteristic of explanatory hypothesis according to anxiety type after conducting five step-by-step experiments related to action and reaction concept. Results found that students who belonged to the types of 'conviction in logical misconception', 'insisting on additional variables', and 'reasonable modification' suggested explanatory hypothesis close to physical nature. On the other hand, those who showed the other five types of anxiety ('compatible predictions', 'dependence on others', 'fusion of past experience', 'lack of confidence', and 'conflict with past experience') suggested temporary supported hypothesis or simple explanatory hypothesis according to student intuition and simple observation. These results indicate that students in the above-mentioned five categories need more external interactions with instructors based on the type of anxiety related to student behavior. In addition, the results present student characteristics which instructors should be more attentive to when using step-by-step experiments to resolve cognitive conflicts.

• Journal of The Korean Association For Science Education
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• v.24 no.6
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• pp.1143-1157
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• 2004

The purpose of this study was to develop HS-VOSTS(High School Students' Views On Science-Technology-Society), which is an instrument that monitors high school students' views on STS. For this study, 23 multiple-choice items were developed on four categories. First, a categorial scheme was constructed. The categorial scheme was based on many instruments that evaluate students' understanding on STS, literature review, and STS learning goal that many researchers had asserted. Second, the multiple-choice items were developed. The development of the items was carried out through four steps. In the first step, some pairs of statement on each subordinate category were formed. Next, the student statement questionaries which were based on the pairs of statement were responded by 772 students. In the second step, the response written by the students were analyzed to common viewpoints and the first multiple-choice items were constructed. In the third step, the semistructured interview with 28 high school students was implemented and the second multiple-choice items were constructed. In the fourth step, the final version of the instrument was developed through the analysis of the students' response on the second multiple-choice items. HS-VOSTS is an useful instrument for monitoring students' beliefs and viewpoints on STS topics. The results of the students' responses to HS-VOSTS items reflect the students' own thoughts directly. These results will give some implications for the curriculum developers, the authors of text books and the educational policy makers as well as the teachers.

• The Journal of the Acoustical Society of Korea
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• v.32 no.1
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• pp.71-78
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• 2013

This paper describes a multiple audio watermarking using Quantization Index Modulation (QIM) on frequency phase and magnitude response. Proposed embedding procedure is composed of two stage. At the first stage, the watermark is embedded on the frequency phase response using QIM. In the second stage, the watermark is embedded using adaptive QIM with the step-size that is adaptively determined using the maximum value of the frequency magnitude response of every frame. The watermark is extracted by calculating the Euclidean distance as the blind detection. The proposed method is robust against most of attacks of audio watermark benchmarking. For the Fourier attacks, the proposed method shows over 95% recovery rate.

• The Journal of the Korea Contents Association
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• v.21 no.1
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• pp.561-571
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• 2021

The 2017 Pohang earthquake left us with issues related to long-term repair and restoration from massive earthquake damage. The existing Earthquake response manual was insufficient to consider the flow of earthquake disaster work and the characteristics of long-lasting earthquake disaster. Accordingly, It is important to analyze and record how to earthquake response work was carried out during the Pohang earthquake. The functions that require the most work and manpower in the event of an earthquake disaster were emergency life stabilization support, facility emergency recovery, and energy functional restoration. As a result of analyzing the difficulties and problems of disaster response by function, it was found that the prevention and preparation for damage in advance was insufficient for each function. In conclusion, we subdivided the response step applied with the concept of time and presented the overall work flow process for thirteen collaboration functions. It is expected that this result will help disaster managers to work effectively in the event of a large scale earthquake.