• Journal of the Korean Institute of Educational Facilities
• /
• v.13 no.4
• /
• pp.31-42
• /
• 2006

This study is about an analysis of the relation between the degree of cognition of student's acts within limits when coping with several types of disaster and the degree of cognition of damage by disasters in the method of multiple regression analysis. The dependent variable is the degree of cognition of student's acts within limits and the independent variable is the degree of cognition of damage by disasters such as heavy snow, typhoon, heavy rain, heat, and yellow sand. A survey of graduates of metropolitan area high-schools has found that there are no difference between girls and boys of the degree of cognition of student's acts within limits when coping with disasters. This study finds that the independent variable, which are playgrounds, animals and plants, streets and roads, altitude and incline, gives positive effect to the degree of cognition of student's acts within limits when coping with typhoon or heavy rain in order. The study also finds that the degree of cognition of student's acts within limits when coping with heavy snow is affected positively by streets and roads, playgrounds, altitude and incline in order. It also shows that there are factors that has an effect to the degree of cognition of student's acts within limits when coping with yellow sand and heat. This study proposes suggestions to facility plans based on these facts discovered.

• Journal of the Korean Institute of Rural Architecture
• /
• v.20 no.1
• /
• pp.19-26
• /
• 2018

The roof improvement project is being carried out under the government's leadership for the sake of national welfare. The project is to replace the asbestos slate roof with a metallic one. In this study, the structural safety of the improved roof was examined and the project guidelines were reviewed. The causes of the roof damage were investigated and the structural analysis was performed for the roof frame subject to wind and snow loads. Metallic roof assemblies have higher strength and load resistance capability than usual slate ones, so the structural safety is governed by the frame. The stresses of the roof frame elements caused by the wind and snow loads were analyzed according to roof frame with various spacings between the rafters and the purlins. Wind load analysis was performed by 24, 28, and 38 m/sec of the basic wind speed. Snow load analysis was carried out by 0.5, 1.0 and $2.0kN/m^2$ of the ground snow load. As the analysis result, the current spacing and the size of the lumber did not satisfy the Korean building code specification. To secure the safety of the roof improvement project, the spacing of the roof frame elements and the size of the lumber should be determined based on the analysis results by structural engineers.

• Atmosphere
• /
• v.29 no.3
• /
• pp.269-282
• /
• 2019

While it is important to obtain the accurate information on snowfall data due to the increase in damage caused by the heavy snowfall in the winter season, it is not easy to observe the snowfall quantitatively. Recently, snow measurements using a weighing precipitation gauge have been carried out, but there is a problem that high snowfall intensity results in low accuracy. Also, the observed snowfall data are sensitive depending on wind speed, temperature, and humidity. In this study, a new process of quality control for snow water equivalent (SWE) data of the weighing precipitation gauge were proposed to cover the low accuracy of snow data and maximize the data utilization. Snowfall data (SWE) observed by Pluvio, Parsivel, snow-depth meter using laser or ultrasonic, and rainfall gauge in Cloud Physics Observation Site (CPOS) were compared and analyzed. Applying the QC algorithm including the use of number of hydrometeor particles as reference, the increased SWE per the unit time was determined and the data noise was removed and marked by flag. The SWE data converted by the number concentration of hydrometeor particles are tested as a method to restore the QC-removed data, and show good agreement with those of the weighing precipitation gauge, though requiring more case studies. The three events data for heavy snowfall disaster in Pyeongchang area was analyzed. The SWE data with improved quality was showed a good correlation with the eye-measured data ($R^2$ > 0.73).

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.3
• /
• pp.246-252
• /
• 2020

Safety accidents have been reported due to falling accumulated snow from cables of cable-supported bridges. In addition to the direct damage caused by falling snow, secondary damage, such as traffic accidents, can occur. Various methods have been proposed to prevent these accidents, but there are still problems in safety and practicality. In this study, a cable robot type was selected as one of the active methods for removing accumulated snow on cables. An attempt was made to increase the climbing ability of the robot to improve the efficiency of snow removal. In addition, the available range of cable diameter for the robot can be adjusted flexibly to be applied to cables used in the field. A high-resolution camera was also installed to check the surface condition of the cable in real time to increase the utility, and be used as a cable inspection robot. A three-axis accelerometer and a tension conversion algorithm were added to measure the tension force of cables. To verify the performance, indoor and field experiments were conducted, and future improvements for the inspection robot were proposed.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.10 no.4
• /
• pp.1-7
• /
• 2010

Recently, the damage of the farmhouse has been increased due to frequent collapsing accidents of the pipe greenhouse caused by the heavy snow load derived from unusual weather phenomena. However, the study about it is rare and tenuous so that the damage is happened repeatedly. Although there are a few ways to improve the greenhouse such as increasing section, decreasing the distance between rafters in order to avoid the collapsing accidents, those ways have some shortcomings like cost and frame ratio increase, etc. Therefore, this study performed the large displacement analysis considering geometric non-linearity on each load level with respect to many kind of reinforcement methods and analyzed combined strength ratio and stress so as to search the ways, which enhance the structural stability of greenhouse and minimize the frame ratio increase. As a result, this paper is aimed at suggesting the optimal reinforcement method model.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.37 no.1
• /
• pp.19-28
• /
• 2017

In this paper, detailed safety inspection reports on the 915 expressway bridges which had been published from 1996 to 2010 are collected and condition of these bridges are analyzed. Damages are categorized into 'damage by defect', 'damage by physical force', and 'damage by deterioration' and the concept of damage possession rate is introduced to investigate the occurrence time and the characteristics of damages. Based on the top 10 damage patterns of expressway bridges and the deterioration characteristics of heavy snow and freezing cold area, reasonable improvement direction of inspection activity is suggested. From this study, it is known that improvement of inspection regularization during construction or at completion stage of bridges is needed. Since the deterioration progress of the heavy snow and freezing cold area is faster than that of general area, environmental characteristics should be considered in inspection activity. The results of present study can be widely used for improvement of inspection activity of expressway bridges.

• Journal of the Society of Disaster Information
• /
• v.13 no.2
• /
• pp.163-172
• /
• 2017

Because of abnormal weather, a heavy snow on the Northern latitudes occurs frequently. This has resulted in significant damage and recovery costs. In korea, it has been declared a special disaster area due to heavy snowfall in Gangneung and Pohang 2004, 2005 and 2011, so there was a revision of action instruction for the road snow removal. Although, in our current system, snow removing methodology, regional equipment holdings, and snow responsible interval, respectively, has been classified by the National Highway, near cities and provinces support system not yet prepared. Only, if snow removing is not possible within the region itself, which contained the contents of "support and assistance to military or nearby offices requests". In this thesis, we studied the disaster scenario development according to heavy snow and the response and support system to the features of each regional. For the scenario deduction, we preferentially collected day snowfall and disaster yearbook data to regionals, classified similar pattern and plotted GIS snow map. We also classified heavy snow disaster by region and type and we deduced five-step scenario. The five-step scenario is nationwide(1st-stage), the National Capital region(2nd-stage), the Chungcheong Provinces(3rd-stage), the Kangwon province(4th-stage) and the Ch?l a provinces(5th-stage). Therefore we build near provinces support system according to five-step scenario.

• Journal of Korean Ophthalmic Optics Society
• /
• v.12 no.4
• /
• pp.19-22
• /
• 2007

Recently, the population of people exploring High Mountain trekking or expedition is increasing as an increase in the backpackers. Many accidents occurring at High Mountain above 6,000 m are the results of snow blindness. The damage of cornea and/or retina is direct cause of snow blindness. The UV intensity increases on the hand, along with the altitude caused by decrease in the atmospheric pressure, on the other hand the reflections by bright snow at high mountain area. And it increases approximately 3 times and 4 times higher than the ground level at altitude of 4,000 m and 8,000 m, respectively. The use of sunglasses is more favorable than goggles for the protection of snow blindness at High Mountains. The eye frames that have high mechanical strength and the plastic lenses which can protect UV 100% are recommended. The attachable shielding pads are needed to prevent the incident UV light reflected or scattered from the gap between glasses frame and face. The sunglasses must have flexible and long temples to wind the ears adequately for the prevention of detachment during climbing and it is recommended that the metal frame to be coated with plastics to prevent the eye surroundings from frostbite.

• Current Research on Agriculture and Life Sciences
• /
• v.31 no.4
• /
• pp.280-285
• /
• 2013

This study supplies basic data to develop a greenhouse model for reducing the damage to single-span greenhouses caused by strong winds and heavy snow. Single-span plastic greenhouses are predominantly used for growing crops in Korea. Thus, the safety wind speeds for single-span greenhouses were calculated and compared with the actual wind speeds and snow depths over a period of 8 years in different regions to analyze the structural safety of single-span greenhouses. The unit wind load and unit snow load were applied to different designs of single-span greenhouse according to the cultivated crop to achieve a structural analysis. As a result, the maximum section force for the wind and snow load was greatest for leaf and root vegetables, where the safety wind speeds for single-span greenhouses according to the cultivated crop were 17.7 m/s(leaf vegetables), 20.2 m/s (fruit vegetables), and 22.3 m/s (root vegetables). Thus, the single-span greenhouses were not found to be safe for the wind load in most regions, except for Hongcheon, Icheon and Sungju. Plus, the safety snow depths for single-span greenhouses according to the crop were 8.8 cm (leaf vegetables), 9.4 cm (fruit vegetables), and 11.8cm (root vegetables). Thus, when comparing the safety snow depths with the actual snow depths, the single-span greenhouses were not found to be safe. Therefore, to improve the safety of single-span greenhouses, the structures need reinforcement by reducing the interval between rafters or increasing the size of the pipes. However, additional research is needed.

• Proceedings of the Korean Society for Bio-Environment Control Conference
• /
• 2005.10a
• /
• pp.138-144
• /
• 2005