• Fire Science and Engineering
• /
• v.19 no.4 s.60
• /
• pp.75-79
• /
• 2005

This study has developed Forest Fire Occurrence Danger Index (FFODI) using fuel and topographical characteristics for the practical purposes of forecasting forest fire occurrence danger rating. This was made on the basis of the 126 forest fire site according to field survey. The result of fire frequency analysis showed 87 sites on conifer $(69\%)$, 21 on mixed $(16.7\%)$ and 18 $(14.3\%)$ on non-conifer. The scale for Fuel Model Index(FMI) ranges from 1 to 10 and Topography Model Index(TMI) from 1 to 5. FMI is 10 on the conifer, 3 on the mixed and 2 on the non-conifer. In case of topographical analysis, it was estimated that 90 site $(71.4\%)$ of ignition point was bottom foot hill and 22 site $(17.5\%)$ was on the southwest. TMI in southwest direction is 5.0, 4.5 in the northwest and the northeast, 4.0 in the southeast and the south, 2.5 in the north and the west and 1.5 in the east. TMI in the bottom foot hill is 5 in the bottom foot hill, 1.5 in the upper foot hill, 1.0 in the bottom middle slope and 0.5 in the upper middle slope and bottom ridge.

• Journal of Astronomy and Space Sciences
• /
• v.30 no.3
• /
• pp.169-174
• /
• 2013

BOH magnetometer was installed at Mt. Bohyun in 2007 and has provided continuous dataset for 3-axis geomagnetic field over the South Korea. We have calculated real-time K-index based on BOH magnetic field data using well-known FMI method. Local K-index is calculated eight times a day, per every three hours. To calculate K-index, it is critical to get the Quiet Day Curve (QDC). For QDC calculation, we take the previous one month's average of H-component. In this paper, we compared four geomagnetic stations' magnetic field data over South Korea and Japan and K-indices of each stations; Bohyun, Gangneung, Jeju, and Kakioka for two years data, 2011-2012. To investigate the difference depending on the latitude, longitude and local time in more detail, we compare K-index on International Quiet Days (IQDs) and International Disturbed Days (IDDs). As a result, we report the correlation between local K-indices are higher than those between Kp and local K-indices, and the correlation is much better after sunset than after sunrise. As the geomagnetic activity becomes stronger, the correlation between the local K-indices and global Kp-index become higher.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.15 no.1
• /
• pp.122-128
• /
• 2016

The purpose of this study was to develop improved strength of an arm and a boom on over-load environment, which causes damage in the initial design statement. To develop improved strength of an excavator front group, we calculated load conditions using the MATLAB program, and using these conditions, we performed a structural analysis of an excavator front group for the maximum digging force condition. Finally we performed a topology optimization to reduce weights of an arm and a boom, and we re-modeled an arm and a boom based on the topology design results and re-performed the structural analysis. The strength of the re-design is higher than the initial design but its weight is almost the same as the initial design.

• Journal of Aerospace System Engineering
• /
• v.9 no.2
• /
• pp.51-56
• /
• 2015

In the vibration test, Most of the test specifications is standardized methods of sinusoidal excitation. However, in accordance with the ability of the test equipment progress and developments of electronic technology, methods of random vibration test is standardized in the MIL standard. Therefore, in this study, we tried to analyze Missile Guidance Structure using a finite element analysis with ABAQUS 6.13 that is commercial program. First, Random response analysis is analyzed. Following analyzing the results, we wanted to find the model that is lightweight and resonance does not occur.

• Journal of Korean Public Health Nursing
• /
• v.34 no.2
• /
• pp.225-237
• /
• 2020

Purpose: This descriptive correlational study examined the acculturation, health literacy, and factors affecting the health literacy of Vietnamese and Chinese female marriage immigrants. Methods: The sample consisted of 90 Vietnamese and 89 Chinese female marriage immigrants who participated in Multicultural Family Support Centers' programs in metropolitan city A. The health literacy was measured by HLI-FMI (Health Literacy Index for Female Marriage Immigrants), acculturation was measured using the Acculturation Index for female marriage immigrants. Descriptive statistics, t-test, Chi-square, one-way ANOVA, Scheffé test, Pearson correlation coefficient, and multiple linear regression were performed for data analysis. Results: The Chinese group (M=9.80±2.72) showed a significantly higher health literacy than the Vietnamese group (M=8.07±3.57). The factors affecting health literacy among Chinese were the length of residence (β=.442 p<.001), and adaptation to Korean culture (β=.381, p=.007). Conclusion: To develope graded education programs for promoting the health literacy of Chinese and Vietnamese female marriage immigrants, the length of residence can be considered. Continuously providing a support system to help them adapt to Korean culture can also have a positive effect on health literacy.

• Journal of Aerospace System Engineering
• /
• v.11 no.1
• /
• pp.22-27
• /
• 2017

In this paper, a walking vibration sensing system (WVS system) using a Fiber Bragg Grating sensor (FBG sensor) is proposed. The seismic part of the FBG sensor was redesigned for sensitivity enhancement. The external excitation was assumed to be the walking cycle of an adult male. The FBG seismic sensor was redesigned using CATIA and ABAQUS such that the sensor's first mode natural frequency is 3.5 Hz (which is a value near the external excitation frequency). Compared with existing walking vibration sensing systems, this newly created system improves sensitivity 15 times. It is also suitable for intrusion detection applications.

• Journal of Aerospace System Engineering
• /
• v.13 no.5
• /
• pp.39-48
• /
• 2019

The turbulent flow in the rotor-stator mixer is based on shear characteristics generated by the interaction of the stator with the rotor rotating at high speed. In this study, the flow characteristics analysis of the unsteady state generated by the interaction of the rotor and the stator in the prototype model of the emulsion-fuel related mixer development was performed with the MRF and SMM by applying the ANSYS FLUENT $k-{\varepsilon}$ (RKE) turbulence model. The behavior and shear characteristics of the flow particles generated at the interface between the designed rotor and stator, and trends such as velocity distribution and turbulence eddy dissipation, were predicted and verified using the CFD analysis.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2021.11a
• /
• pp.72-73
• /
• 2021

In this study, the engineering characteristics of CLSM mixed with GBFS and GF were identified to review the applicability as a replacement material and further evaluate the recharge and field applicability as a joint filler material. First, Using more than 30% of GBFS to replace FA enabled bleeding control through improved fluidity. Second, When using more than 30% of FNS to replace sand, it was found that adding 0.25~0.35 of the AE agent is effective for bleeding control through improved fluidity. Third, When using more than 30% of both GBFS and FNS in combination, it was found that adding 0.3~0.35 of the AE agent is effective for bleeding control through improved fluidity. Also, it was confirmed that proper mixing of 15~60% of GF secured the effective strength and desired quality as a refiller and joint filler material.

• Journal of Aerospace System Engineering
• /
• v.13 no.1
• /
• pp.1-10
• /
• 2019

The flow characteristics in a stirred tank are very useful in a wide variety of industrial applications. Generally, the flow pattern, power consumption and mixing time in stirred vessels depend not only on the design of the impeller, but also on the tanks' geometry and internal structure. In this study, the analysis of an unstable and unsteady complicated flow characteristics generated by the interaction between the baffle shape and impeller were performed using the ANSYS FLUENT LES Turbulence Model. The study compared the predictions of CFD with the interaction between two types of rotating impellers (axial and radial flows) and the shapes of three baffles. The results of the comparison verified that the design model showed a relatively efficient trend in the mixing flow fields and characteristics around the impeller and baffles during agitation.

• Journal of IKEEE
• /
• v.22 no.4
• /
• pp.1073-1078
• /
• 2018

As interest in the 4th Industrial Revolution increases, the CPS, in which things existing in the reality and things existing in the virtual interact with each other, is attracting attention as an important technology. Complex systems such as electric vehicles, autonomous driving, smart factories, and smart grid system are considered as core technology fields of the 4th Industrial Revolution, and many types of research have been conducted to develop it. The reliability of the system is directly related to the safety of people in case of the autonomous driving, and verification of the actual vehicle's hardware and software of ADAS is essential. In this paper, we proposed distributed simulation middleware supporting HILS for reliable verification of the complex hybrid systems.