• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.6
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• pp.539-543
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• 2006

Lodging is classified as root lodging caused by the loss of supporting force in the root, bending caused by the deformation of the stem and breaking where the stem breaks down as loads exceeding critical elasticity were applied. This research excluded breaking which is not in a state of equilibrium and tried to partition the level of lodging using an algebraic model in root lodging and stem lodging, or bending. When a vertical load was applied, the deformation of the stem of rice plant showed the form of a quadratic equation. The trace of the panicle neck in the process of lodging was an ellipse-shape. When loading was pure root lodging, the trace of the panicle neck became a circle of which culm length is the radius. When it was a pure stem lodging, the trace of the panicle neck is an ellipse of which major axis is culm length and minor axis is 0.64* culm length. When both stem lodging and root lodging occurred in a natural setting, the partitioning of lodging can be calculated by a formula using eccentricity of an ellipse, S=e*100/0.768(S is the ratio of stem lodging in the whole lodging, e is eccentricity of the ellipse). This method is expected to be useful in simple lodging partitioning. We could also calculate the partitioning of stem lodging and root lodging as units of angles as an accuracy method, by using a straight line calculated by differentiating a quadratic equation of stem deformation at the origin of the coordinates. These two methods for dividing root and stem lodging showed different values. However, each of them showed almost same values with different lodging degree in one plant.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.12B
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• pp.1387-1398
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• 2009

In the latest we will make a demand for the precision position estimation for the Mobile-station(MS)'s position. But, we have a lot of problems the position estimation method using the existing method. The Base-station(BS) measure a distance according to time delay waves to receive propagate from the MS and estimate the position using the existing circle equation with method to be selected BSs in close proximity the MS. It knows that happens a lot of error the estimated position and the true position. This paper propose that the method is selected round BSs to estimate for MS's position and estimated the angle using the second law of cosine. This paper demonstrate that using simulation the proposal method is a predominant method to compare with the existing method.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.3
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• pp.95-108
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• 2019

Quality management has become an pervasive philosophy in most sectors of business. Specific movements such as statistical quality control, quality circle, total quality management, and quality management system have become embedded in business organizations. Only the companies with competitive edge can survive in the competition in global market. KSA(Korean Standards Association) established in 1962 has launched all kinds of quality education, quality standard certification service for business, and KNQA(Korean National Quality Award) system. This article considers quality competitiveness excellent company award among KNQA. We performed a statistical analysis of audit data for quality competitiveness excellent company for three years, from 2015 to 2017. By using ANOVA and two sample t-tests, the average scores of 13 evaluation fields were significantly different depending on company size and type. We proposed ways to improve the current hall of fame system. We discovered that the average scores of 13 evaluation fields in the audit data according to years and hall of fame status were not significantly different. We also showed linear relationships among 13 evaluation fields by correlation analysis and obtained an estimated linear regression equation : Business Performance, which is a comprehensive index, as a dependent variable was significantly related to Customer Focus and Product Liability as regressor variables among 13 evaluation fields by regression analysis.

• The Journal of the Acoustical Society of Korea
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• v.26 no.8
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• pp.375-380
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• 2007

A reverberation chamber should be designed and constructed so as to satisfy its purposes and available space. However, it is somewhat difficult to meet the intended design requirements due to various errors from construction process. So, the post-construction measurement of its volume and surface areas is very essential to check the actual volume and volume uncertainty of a reverberation chamber These values should be carefully calculated and accurately estimated since they are used not only to evaluate the acoustic characteristics of building materials but also to calculate uncertainties for other acoustic characteristics. In this work, the method for the calculation and uncertainty estimation of the volume of a reverberation chamber is presented. To this end, the coordinates of all corners was measured with Total Station after construction. The results showed that the calculated volume of the measured reverberation chamber differs by 5 % from the design specification. The expanded volume uncertainty was also estimated to be about 2 % of the total calculated volume.

• The Journal of Korean Institute of Next Generation Computing
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• v.15 no.3
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• pp.25-30
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• 2019

Magnetic sensors have the disadvantage that their vector values differ depending on the direction. In this paper, we propose a magnetic vector calibration method for geomagnetic-based indoor localization estimates. The fingerprinting technique used in geomagnetic-based indoor localization the position by matching the magnetic field map and the magnetic sensor value. However, since the moving direction of the current user may be different from the moving direction of the person who creates the magnetic field map at the collection time, the sampled magnetic vector may have different values from the vector values recorded in the field map. This may substantially lower the positioning accuracy. To avoid this problem, the existing studies use only the magnitude of magnetic vector, but this reduces the uniqueness of the fingerprint, which may also degrade the positioning accuracy. In this paper we propose a vector calibration algorithm which can adjust the sampled magnetic vector values to the vector direction of the magnetic field map by using the parametric equation of a circle. This can minimize the inaccuracy caused by the direction mismatch.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.5
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• pp.487-499
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• 2009

The postprocessing technology has been advanced diversely to accommodate the tendency of increasingly refined and complicated practices of finite element modeling in pace with enhanced capabilities of computers and improved algorithm of equation solvers. As a result of such progresses in both hardware and software, it became practically meaningful to inspect and analyze the elasto-plastic behavior using the intermediate results from the increasing number of incremental and iterative processes. This paper is concerned about the new methods of postprocessing with computer graphic visualization of elasto-plastic behavior on the basis of the theoretically reorganized analysis results. This paper proposes a new method of rendering the plastic zone, and new approaches of analyzing and interpreting the elasto-plastic behavior using the graphical information visualized in the form of the yield surface and the stress path, or in the form of the Mohr circles and the failure envelope.

• Journal of Korea Water Resources Association
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• v.49 no.1
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• pp.61-72
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• 2016

In Korea, the aquifers at the coastal areas are mostly shallow alluvial unconfined aquifers. To simulate the flow and dispersion in unconfined aquifer, a FDM model has been developed to solve the nonlinear Boussinesq equation. Related analysis and verification have been executed. The iteration method is used to solve the nonlinearity, and the model shows 3-D shape because it is a 2-D y model that consider the undulation of water table and bottom. For the verification of the model, the output of flow module is compared to the 1-D analytic solution of Lee (1989) which have the drawdown or uplift boundary condition, and the two results show almost the same value. and the mass balance of dispersion module shows about 10% error. The developed model can be used for the analysis and design of the flow and dispersion in the unconfined aquifers. The model has been applied to the estuary area of Ssangcheon watershed, and the parameters have been deduced as a result : hydraulic conductivity is 90 m/day, and longitudinal dispersivity is 15 m. And the analysis with these parameters shows that the wells are situated in the influence circle of each others except for No. 7 well. Groundwater discharge to sea is $3700m^3/day$. And the chlorine ion ($cl^-$) concentration at the pumping wells increase at least 1000 mg/L if groundwater dam is not exist, so the groundwater dam plays an important role for the prevention of sea water intrusion.

• Journal of Distribution Science
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• v.11 no.6
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• pp.81-89
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• 2013

Purpose - The market orientation of a manufacturer is a very critical competitive advantage factor in the development of new markets and the sustainability and maintenance of existing ones, achieved through the design of customer-oriented products. This is recognized as a virtuous circle, in which firms grow by means of promoting quality management. However, though market-oriented activities are important in management and operations, they seem to be promoted mainly by large-scale enterprises rather than by small- and medium-scale firms, the latter having invested relatively few company resources. Furthermore, few studies and analyses have examined how market orientation relates to the expansion of quality programs within organizations or with business performance; the market orientation and customer-orientation concepts are mixed together when both are used in research. Given the current market situation in which the servitization of manufacturing firms is rapidly expanding, this study's analysis of the effect on market orientation of manufacturers is a significant contribution. From this perspective, this study has several objectives. First, is to analyze and suggest the relationship between market orientation and quality management activity for manufacturers, focusing on three sub-activities: products, process, and quality management activities. Second, it is intended to identify correlation between manufacturers' market oriented activity and their management performance and then to analyze how market orientation affects business performance. The results of a number of prior studies on the correlation between market orientation and management performance have indicated that market orientation does affect management performance. Third, this study also investigates whether any differences in the relationship among market orientation, quality management activity and business performance occur according to company size. The results are used to present operational suggestions for large- and small- and medium-size firms. Research design, data, methodology - This study seeks to analyze and identify the causal features of the organic relationship among market orientation, quality management, and management performance for Korean manufacturing companies using three years (2005-2007) of market orientation, quality management, and business performance data. Subsequently, structural equation modeling was used to analyze the causal features of related factors and it aims to identify the features of market orientation, quality management, and business performance. Results - The analysis examined how market orientation affected the quality management and management performance of 159 smalland medium-size companies. In particular, enterprise quality management was analyzed in relation to management performance with a focus on activities such as leadership, measurement and improvement, quality control, cost management, and process management. Conclusions - The result of the analysis show that market orientation significantly affected all of the quality management activities and that market orientation in turn significantly affected organizational performance. The result of analysis indicate that quality management activities have a significant effect on quality control and cost management.

• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.1
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• pp.51-61
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• 2014

It is necessary to perform a dynamic analysis to numerically evaluate the effect of blasting on nearby facilities. The blast load time history, which cannot be directly measured, is most often determined from empirical equation. The load has to be adjusted to account for various factors influencing the load and the frequency, but there is not a clear guideline on how to adjust the load. In this study, a series of 2D dynamic numerical analyses that simulates a closely monitored test blasting is performed, from which the blast load that matches the measured vibrations are derived. In the analyses, it is assumed that the hole generated by the blasting is in the form of a circle, and the load was applied normally to the wall of the opening. Special attention was given in selecting the damping ratio for the ground, since it has important influence on the wave propagation and attenuation characteristics of the blast induce waves. The damping ratio was selected such that it matches favorably with the attenuation curve of the measurement. The analyses demonstrate that the empirical blast load widely used in practice highly overstimates the vibration since it does not account for the energy loss due to rock fragmentation. If the empirical load is used without proper adjustment, the numerical analysis may seriously overstimate the predicted vibration, and thus has to be reduced in the analysis.

• Journal of the Korean GEO-environmental Society
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• v.16 no.12
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• pp.5-12
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• 2015

Since blasting noise is impact noise, it will give a sudden shock to the human. In the case, such as the blast vibration, it has given aging buildings and livestock great damage to move the vibration along ground in nearby regions. In this study, the influence of the blasting generated during excavation was analyzed for effects on regional. A couple of field and laboratory surveys about geological were carried out to figure out the geological ratio in the study-performed area. Blast vibration noise was compared to the domestic and abroad case studies and each of the institutions permissible standards established the most appropriate criteria in site condition. The vibration velocity of blasting vibration exploits the values which were measured from test blasting on the ground in order to examine blasting effect. Considering the blasting point as the shortest distance from safety facilities (farms, private houses, etc.), the examination of the influence range, which was derived from the vibration velocity of blasting vibration, was performed to figure out how the point affected the safety facilities. Three-dimensional numerical analysis was performed a time history analysis in order to analyze the behavior of the structure for a dynamic blast load, which was determined in three directions of the blast vibration value. The results of three-dimensional numerical analysis and the blasting effect of blasting vibration estimation equation blasting vibration of impact circle with accompanying test blasting were compared. And the analysis confirmed similar results figures.