• The Journal of the Convergence on Culture Technology
• /
• v.10 no.2
• /
• pp.201-208
• /
• 2024

In this study, we investigated whether the evacuation time according to the exit installation standards specified in the building code during a food factory fire is compatible with the evacuation time based on the performance-based design specified by the fire department, in order to determine if evacuation safety is ensured. We used the Pathfinder program to confirm the evacuation time, and experimented with three scenarios for exit installation standards towards the outside of the building: 60m, 80m, and 100m. The target building in the experiment corresponded to the building code's exit installation standard of 100m from each dwelling. The experimental results showed tt in the cases of 80m and 100m, ASET exceeded RSET, indicating tt evacuation safety was not ensured, while in the case of 60m, evacuation safety was maintained. Through this study, it was confirmed tt even when the exit installation standards towards the outside of the building are met, evacuation safety may not be guaranteed.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.26 no.2
• /
• pp.113-128
• /
• 2024

Items of road tunnel PISD (Precise Inspection for Safety and Diagnosis) were reviewed and analyzed using newly enhanced MMS (Mobile Mapping System) technology. Possible items with MMS can be visual inspection, survey and non-destructive test, structural analysis, and maintenance plan. The resolution of 3D point cloud decreased when the vehicle speed of MMS is too fast while the calibration error increased when it is too slow. The speed measurement of 50 km/h is determined to be effective in this study. Although image resolution by MMS has a limit to evaluating the width of crack with high precision, it can be used as data to identify the status of facilities in the tunnel and determine whether they meet disaster prevention management code of tunnel. 3D point cloud with MMS can be applicable for matching of cross-section and also possible for the variation of longitudinal survey, which can intuitively check vehicle clearance throughout the road tunnel. Compared with the measurement of current PISD, number of test and location of survey is randomly sampled, the continuous measurement with MMS for environment condition can be effective and meaningful for precise estimation in various analysis.

• Applied Chemistry for Engineering
• /
• v.35 no.1
• /
• pp.29-36
• /
• 2024

The fire risk and fire safety of four types of wood were comprehensively evaluated according to Chung's equation-XII. White ash, willow, fraxinus mandshurica, and sagent cherry trees were selected as test specimens. A cone calorimetery (ISO 5660-1) was used to examine the combustion characteristics of the test piece, and finally, the fire risk rating (FRR) was predicted using the fire risk index-XII (FRI-XII). The predicted fire performance index-X (FPI-X) and fire growth index-X (FGI-X) ranged from 469.03 to 1109.73 s²/kW and 0.0009 to 0.0280 kW/s², respectively. Additionally, the fire performance index-XI (FPI-XI) and fire growth index-XI (FGI-XI) ranged from 0.41 to 0.97 and 1.11 to 3.11, respectively. The fire risk index-XII (FRI-XII), representing a fire risk rating, showed that the fire risk of frasxinus mandsurica tree (FM) was very high at 7.60 (fire risk rating: D). And it was compared with Chung's equation-IX, fire risk index-IX (FRI-IX). The fire risk ratings according to FRI-IX and FRI-XII were generally high for willow and frasxinus mandsurica trees. Additionally, the results of FRI-XII and FRI-IX had a similar relationship, and the size of each fire safety rating closely matched each other.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.23 no.2
• /
• pp.69-78
• /
• 2024

Recently, the use of CCTV to prevent crowd accidents has been promoted, but research is needed to compensate for the spatial limitations of CCTV. In this study, pedestrian density was measured using drone footage, and based on a review of existing literature, a threshold of 6.7 people/m² was selected as the cutoff risk level for crowd accidents. In addition, we conducted a preliminary study to determine drone parameters and found that the pedestrian recognition rate was high at a drone altitude of 20 meters and an angle of 60°. Based on a previous study, we selected a target area with a high concentration of pedestrians and measured pedestrian density, which was found to be 0.27~0.30 per m². The study shows it is possible to measure risk levels by determining pedestrian densities in target areas using drone images. We believe drone surveillance will be utilized for crowd safety management in the near future.

• Journal of Digital Convergence
• /
• v.21 no.3
• /
• pp.49-62
• /
• 2023

Due to social and cultural changes and the growth of aging people living as a single because of aging, lonely deaths are steadily increasing, and each local government has begun to define them as a social problem. The legal basis began to be established. In order to explore policy measures to prevent lonely deaths, this study examined cases of lonely death prevention policies using smart digital information technology (AI, IOT), which is being promoted by Daegu Metropolitan City to promote non-face-to-face policies to prevent lonely deaths. Policies related to lonely deaths are divided into two axes: lonely death prevention projects and post-excavation support projects. In order to operate these businesses efficiently, the provision of non-face-to-face services through artificial intelligence and the Internet of Things is recognized as a new service delivery system, so the importance and necessity of non-face-to-face services is increasing. It is time that multifaceted changes and preparations are needed, such as establishing a system to expand the non-face-to-face industry at the national level. In order to respond to another national disaster situation in the future, the non-face-to-face smart care system is being expanded in various welfare policies such as preventing lonely deaths. It will have to be activated.

• Journal of Digital Convergence
• /
• v.22 no.1
• /
• pp.1-14
• /
• 2024

In order to improve the effectiveness of carbon neutrality in Jeju Special Self-Governing Province, this study identifies the current state of social environmental education through literature research, excluding school environmental education being implemented in elementary, middle, and high schools in the province, and identifies shortcomings or problems. The purpose is to establish a plan to systematically and integratedly operate social environmental education, and the derived plan can be used as a guide to change environmental awareness and induce eco-friendly behavior to improve the effectiveness of carbon neutrality. As a result of the study, Jeju Special Self-Governing Province established a consultative body with environmental education institutions, organizations and expert groups operating dispersed throughout the province through the substantial operation and support of the environmental education center currently being entrusted, to identify the current status and develop content necessary for establishing environmental education policies, establishing a platform to enable information sharing, role division, regular communication, empathy, and policy feedback, and on-site environmental education centered on the field to stimulate emotions and personalize environmental problems so that environmental problems can be properly recognized. Emphasizing the necessity.

• Journal of Korea Water Resources Association
• /
• v.57 no.3
• /
• pp.195-207
• /
• 2024

This study selected major drought events that occurred in the Jeonnam region from 1991 to 2023, examining both meteorological and hydrological drought occurrence mechanisms. The daily drought index was calculated using rainfall and dam storage as input data, and the drought propagation characteristics from meteorological drought to hydrological drought were analyzed. The characteristics of the 2022-23 drought, which recently occurred in the Jeonnam region and caused serious damage, were evaluated. Compared to historical droughts, the duration of the hydrological drought for 2022-2023 lasted 334 days, the second longest after 2017-2018, the drought severity was evaluated as the most severe at -1.76. As a result of a linked analysis of SPI (StandQardized Precipitation Index), and SRSI (Standardized Reservoir Storage Index), it is possible to suggest a proactive utilization for SPI(6) to respond to hydrological drought. Furthermore, by confirming the similarity between SRSI and SPI(12) in long-term drought monitoring, the applicability of SPI(12) to hydrological drought monitoring in ungauged basins was also confirmed. Through this study, it was confirmed that the long-term dryness that occurs during the summer rainy season can transition into a serious level of hydrological drought. Therefore, for preemptive drought response, it is necessary to use real-time monitoring results of various drought indices and understand the propagation phenomenon from meteorological-agricultural-hydrological drought to secure a sufficient drought response period.

• Journal of Forest and Environmental Science
• /
• v.14 no.1
• /
• pp.112-127
• /
• 1998

A meeting for Japan Society of Erosion Control Engineering took place, from May 20-21 in Sapporo, Japan, with the presentations of 21 special topics and 185 general papers. Special topics consists of 6 copies on volcanic disaster prevention, 6 copies on the activity report of Earthquake Erosion Control Engineering Society, 5 copies on the management and guidelines of riparian zone and 4 copies on debris disaster occurred in 1997. General papers consists of 10 copies on slope stability, 10 copies on slope failure, 9 copies on earthquake, 41 copies on environmental erosion control, 25 copies on debris flow, 11 copies on warning and refuge, 10 copies on erosion control plan, 11 copies on erosion control project, 10 copies on erosion control facility, 12 copies on volcanic erosion control, 4 copies on revegetation technology, 4 copies on forest hydrology, 4 copies on avalanche, 4 copies on landslide, 18 copies on debris flow and 2 other copies presented by international student. Among the special topics, 5 papers with the titles of the function and structure of riparian zone, the interactive relation of flood and riparian zone, the management method of channel and river forest for controlling debris flow, the forest restoration efforts by native population, the law and social issue for building river riparian zone were presented in the subsection of "The Management and Guidelines of Riparian Zone". Thus, this article summarize and introduce the presented contents which are very important and can be referred to keep environmentally sound-river in the erosion control field.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.19 no.3
• /
• pp.75-85
• /
• 2017

A method to estimate hourly temperature profiles on calm and clear nights was developed based on temporal changes of inversion height and strength. A meteorological temperature profiler (Model MTP5H, Kipp and Zonen) was installed on the rooftop of the Highland Agriculture Research Institute, located in Daegwallyeong-myeon, Pyeongchang-gun, Gangwon-do. The hourly vertical distribution of air temperature was measured up to 600 m at intervals of 50 m from May 2007 to March 2008. Temperature and relative humidity data loggers (HOBO U23 Pro v2, Onset Computer Corporation, USA) were installed in the Jungdae-ri Valley, located between Gurye-gun, Jeollanam-do and Gwangyang-si, Jeollanam-do. These loggers were used to archive measurements of weather data 1.5 m above the surface from October 3, 2014, to November 23, 2015. The inversion strength was determined using the difference between the temperature at the inversion height, which is the highest temperature in the profile, and the temperature at 100 m from the surface. Empirical equations for the changes of inversion height and strength were derived to express the development of temperature inversion on calm and clear nights. To estimate air temperature near the ground on a slope exposed to crops, the equation's parameters were modified using temperature distribution of the mountain slope obtained from the data loggers. Estimated hourly temperatures using the method were compared with observed temperatures at 19 weather sites located within three watersheds in the southern Jiri-mountain in 2015. The mean error (ME) and root mean square error (RMSE) of the hourly temperatures were $-0.69^{\circ}C$ and $1.61^{\circ}C$, respectively. Hourly temperatures were often underestimated from 2000 to 0100 LST the next day. When temperatures were estimated at 0600 LST using the existing model, ME and RMSE were $-0.86^{\circ}C$ and $1.72^{\circ}C$, respectively. The method proposed in this study resulted in a smaller error, e.g., ME of $-0.12^{\circ}C$ and RMSE of $1.34^{\circ}C$. The method could be improved further taking into account various weather conditions, which could reduce the estimation error.

• Journal of Korean Society of Forest Science
• /
• v.45 no.1
• /
• pp.62-67
• /
• 1979

Ultraviolet microscopy of ultrathin sections of wood has proved to be one of the useful means for determining the lignin distribution in the various regions of the cell wall. Also, spectral approach and quantitative analysis of isolated compound middle lamella fraction from birch xylem have revealed that the lignin associated with the vessel secondary wall and middle lamella is composed predominantly of gualacylpropane units. Lignin deposited in the fiber and ray parenchyma secondary walls is composed mostly of syringylpropane units. The middle lamella lignin around fibers and ray cells contains both guaiacyl and syringyl propane quits. On the basis of the results above, this research was carried out to clarify the origin of milled wood lignin (MWL) by analysing the chemical characteristics of ML MWLs extracted at various milling stages. The amount of phenolic hydroxyl-, ${\alpha}$-carbonyl-, and methoxyl-group in the MWL's increases the milling time. And progressive mining contributes to the merease of ratio of syringylaldehyde to vanillin(S/V ratio) after nitrobenzene oxidation of MWL. Accordingly, It could be concluded that milled wood lignin extracted at the initial milling stage derives from compound middle lamella region of cell wall, whereas, with progressive milling, lignin of secondary wall of fiber is introduced gradually to milled wood lignin. These results are suggesting that heterogeneous chemical structure of lignins in hardwood exists. Although milled wood lignin at the initial stage seems to have lower molecular weight in comparison with milled wood lignin extracted at final milling stage from the result of Gel-filtration curves, further study would be required on molecular weight distribution of milled wood lignin in future.