• Journal of the Korea Society of Computer and Information
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• v.13 no.5
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• pp.27-35
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• 2008

The CTOC framework was implemented to efficiently perform analysis and optimization of the Java bytecode that is often being used lately. In order to analyze and optimize the bytecode from the CTOC, the eCFG was first generated. Due to the bytecode characteristics of difficult analysis, the existing bytecode was expanded to be suitable for control flow analysis. and the control flow graph was drawn. We called eCFG(extended Control Flow Graph). Furthermore, the eCFG was converted into the SSA Form for a static analysis. Many loops were found in the conversion program. The previous CTOC performed conversion directly into the SSA Form without processing the loops. However, processing the loops prior to the SSA Form conversion allows more efficient generation of the SSA Form. This paper examines the process of finding the loops prior to converting the eCFG into the SSA Form In order to efficiently process the loops, and exhibits the procedures for generating the loop tree.

• Geophysics and Geophysical Exploration
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• v.8 no.1
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• pp.97-103
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• 2005

Recent development of marine magnetic gradient systems, using arrays of sensors, has made it possible to survey large contaminated areas very quickly. However, underwater Unexploded Ordnances (UXO) can be moved by water currents. Because of this mobility, the cleanup process in such situations becomes dynamic rather than static. This implies that detection should occur in near real-time for successful remediation. Therefore, there is a need for a fast interpretation method to rapidly detect signatures of underwater objects in marine magnetic data. In this paper, we present a fast method for location and characterization of underwater UXOs. The approach utilises gradient interpretation techniques (analytic signal and Euler methods) to locate the objects precisely. Then, using an iterative linear least-squares technique, we obtain the magnetization characteristics of the sources. The approach was applied to a theoretical marine magnetic anomaly, with random errors, over a known source. We demonstrate the practical utility of the method using marine magnetic gradient data from Japan.

• PNF and Movement
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• v.19 no.3
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• pp.341-349
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• 2021

Purpose: The purpose of this study was to investigate the effect of soleus muscle stretching on the muscle thickness and muscle tone of the tibialis anterior and peroneus longus muscles in healthy young adults. Methods: This study was an observational, cross-sectional study design in healthy young adults. Thirty healthy young adults participated in the study. To investigate the effect of agonist elongation on the muscles' antagonist and synergist characteristics, this study conducted the dynamic stretching of the soleus and plantarflexor muscles for 20 seconds. This study measured the muscle thickness and muscle tone of the soleus, tibialis anterior and peroneus longus muscles before stretching, immediately after stretching, and five minutes after stretching. Results: After analysis, the muscle tone of the soleus muscle was significantly decreased immediately after stretching (20.91±2.61Hz) compared to before stretching (21.83±2.78Hz). The muscle tone of the tibialis anterior was significantly decreased both immediately after stretching (21.76±2.73Hz) and five minutes after stretching (21.72±3.25Hz) compared to before stretching (22.61±3.29Hz). The muscle thickness of the soleus muscle was significantly decreased immediately after stretching (2.04±0.52mm) compared to before stretching (2.21±0.51mm) and was significantly increased five minutes after stretching (2.14±0.49mm) compared to immediately after stretching. Conclusion: The results of this study showed the static stretching of the soleus muscle changed the muscle tone of the tibialis anterior, but not of the peroneus longus muscle. This study suggests that the dynamic stretching of the agonist muscle would show meaningful muscle tone change in the antagonist.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.8
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• pp.661-669
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• 2021

A mechanical stiffener has been mainly applied on a PCB to secure fatigue life of a solder joint of an electronic components in spaceborne electronics by minimizing bending displacement of the PCB. However, it causes an increase of mass and volume of the electronics. The high damping PCB implemented by multi-layered viscoelastic tapes of a previous research was effective for assuring the fatigue life of the solder joint, but it also has a limitation to decrease accommodation efficiency for the components on the PCB. In this study, we proposed high damping PCB with a multi-layered superelastic shape memory alloy stiffener for spatialminimized, light-weighted, high-integrated structure design of the electronics. To investigate the basic characteristics of the proposed PCB, a static load test, a free vibration test were performed. Then, the high damping characteristic and the design effectiveness of the PCB were validated through a random vibration test.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.8
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• pp.362-370
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• 2019

The internal pressure capacity of a modular containment structure requires analysis to prevent the release of radioactive material in the case of an accident. To analyze the capacity, FEM models were prepared while considering the tendon arrangements and the contact surfaces between precast concrete modules, and then static analyses were carried out. The changing characteristics in the displacement and stress under step-wise loading were analyzed, along with the effects of selected parameters. For comparison, the capacity of a monolithic containment structure was also analyzed. Parametric analyses were done to suggest ranges of parameters such as the tendon force, tendon spacing, tendon location in concrete thickness direction, friction coefficient, and concrete thickness. The tendon force and frictional force provide a combined effect between contact surfaces of modules. The same level of internal pressure capacity can be secured even in the modular containment structure as in the monolithic containment structure by increasing the tendon force with additional tendons.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.401-408
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• 2019

This study numerically examined the maximum wind pressure distribution of a billboard on the roof of a middle-rise building. The deformation caused by the maximum wind pressure was examined. For the numerical analysis, the signboard was assumed to be installed on $(b)20m{\times}(d)10m{\times}(h)$ buildings. The maximum wind pressure was measured using four models with the standard model and different sizes of the signboard. The numerical analysis showed that the horizontal deformation predominantly occurs as the shape of the signboard becomes closer to a rectangle, and high wind pressure and deformation occur at the corners of both ends. As the height of the signboard increases, vertical deformation predominantly occurs, and static pressure forms on the backside. When the height is lower than the width of the signboard, the wind pressure is concentrated on the center of the roof. Therefore, the distribution of the maximum wind pressure is stable, and the effect of the wind pressure is relatively low as the height-to-width ratio approaches 1.

• Atmosphere
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• v.28 no.4
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• pp.357-367
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• 2018

In this study, the temperature bias of aircraft observation was estimated through comparison with sonde observation prior to developing the temperature bias correction method at the Korea Institute of Atmospheric Prediction Systems (KIAPS). First, we tried to compare aircraft temperature with collocated sonde observations at 0000 UTC on June 22, 2012. However, it was difficult to estimate the temperature bias due to the lack of samples and the uncertainty of the sonde position at high altitudes. Second, we attempted a background innovation comparison for sonde and aircraft using KIAPS Package for Observation Processing (KPOP). The one month averaged background innovation shows the aircraft temperature have a warm bias against sonde for all levels. In particular, there is a globally distinct warm bias about 0.4 K between 200 hPa and 300 hPa corresponding to flight level. Spatially, most of the areas showed the warm bias except for below 300 hPa in some part of China at 0000 and 1200 UTC and below 850 hPa in Australia at 0000 UTC. In general, the temperature bias was larger at 1200 UTC than 0000 UTC. Based on the estimated temperature bias, we have applied the static bias correction method to the aircraft temperature observation. As a result, the warm bias of the aircraft temperature has decreased at most levels, but a slight cold bias has occurred in some areas.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.8
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• pp.599-606
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• 2019

The pulse gun device is designed to identify the transverse pressure wave propagation/damping mechanism into the combustion flow field and in the combustion chamber according to the arrangement of multiple injectors. The manufactured pulse gun was tested to verify operability at the target combustion pressure and control of the pressure wave intensity. Gas nitrogen was used to pressurize the high-pressure tube and an OHP film of $100{\mu}m$ thickness was used for the diaphragm. To check the speed and intensity of the pressure waves, the dynamic and static pressure were measured using the pressure transducer. The performance test confirmed that the manufactured pulse gun can generate pressure waves with transverse characteristics that can be controled for strength depending on the supply pressure.

• Journal of Convergence for Information Technology
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• v.9 no.8
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• pp.170-179
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• 2019

This study was narrative research study to find out the effect of adolescents' social media addiction tendencies on interpersonal relationships. This research data was collected from 250 middle high school students in G city, Gyeongnam and collected data was analyzed with t-test, ANOVA, Pearson's correlation, Multiple regression coefficient using SPSS 23.0 program. SNS addiction tendency scores according to general characteristics of adolescents were gender (t= -2.25, p = .011), duration of SNS use (F= 3.15, p= .015), average usage time (F= 15.87, p=. 001), SNS media (F= 3.12, p= .027), and SNS media usage time (F= 6.58, p= .001) were statistically significant. As a result of verifying the correlation of main variables, addiction tendency of SNS had statistically significant static correlation with interpersonal relationships. Influencing factors of interpersonal relations were Addiction tendency of SNS(${\beta}=-.64$, p=.<001) Interpersonal relationship explained 37% of the total variability.

• Convergence Security Journal
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• v.19 no.1
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• pp.11-17
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• 2019

Recently, the abuse of Internet technology has caused economic and mental harm to society as a whole. Especially, malicious code that is newly created or modified is used as a basic means of various application hacking and cyber security threats by bypassing the existing information protection system. However, research on small-capacity executable files that occupy a large portion of actual malicious code is rather limited. In this paper, we propose a model that can analyze the characteristics of known small capacity executable files by using data mining techniques and to use them for detecting unknown malicious codes. Data mining analysis techniques were performed in various ways such as Naive Bayesian, SVM, decision tree, random forest, artificial neural network, and the accuracy was compared according to the detection level of virustotal. As a result, more than 80% classification accuracy was verified for 34,646 analysis files.