• Journal of Conservation Science
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• v.33 no.4
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• pp.255-266
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• 2017

Chemically derived pesticides have been used to prevent biological damage to domestic cultural property. However, their use is gradually being restricted due to the harmful effects on the human body and environment. Therefore, there is a growing interest in the search for new antifungal biopharmaceuticals whose safety has been confirmed by toxicity evaluation through animal experiments. This paper presents methods of toxicity evaluation of natural biocides using Sprague-Dawley rats and New Zealand White (NZW) rabbits. Safety of the natural biocide extract of Asarum sieboldii was evaluated using single-dose oral and dermal toxicity tests in Sprague-Dawley rats, and eye and skin irritation tests in NZW rabbits. The extract has proven antimicrobial and insecticidal activities against wood-rotting fungi and termites. After single oral administration to rats, the $LD_{50}$ values were determined to be over 4,000 and 2,000 mg/kg for males and females, respectively. After single dermal administration to rats, the $LD_{50}$ values exceeded 10,000 mg/kg for both males and females. The extract was identified to be non-irritant to the rabbit eye, and only slightly irritant to the rabbit skin. In this study, we confirmed the safety of the A sieboldii extract through animal testing. Due to the harmfulness of humidifier disinfectants, focus is on the safety of chemical pesticides, and toxicity evaluation is suggested as the basic method for hazard evaluation.

• Journal of Conservation Science
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• v.37 no.5
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• pp.505-515
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• 2021

In this study, we evaluated the slope stability of the Pohang Daljeon-ri columnar joint (Natural Monuments # 415) and calculated the maximum energy, jumping height and moving distance of rockfalls using a simulation. Based on the results, we established the range of rockfall risk. The slopes of the Pohang Daljeon-ri columnar joint have dip directions of 93.79°, 131.99°, 165.54° and 259.84° from left (SW) to right (NE). Furthermore, they have a fan-like shape. The Pohang Daljeon-ri columnar joints are divided into four sections depending on the dip direction. The measurement results of the discontinuous face show that zone 1 is 125, zone 2 is 261, zone 3 is 262, zone 4 is 43. The results of slope stability analyses for each section using a stereographic projection method correspond to the range of planar and toppling failure. Although it is difficult to diagnose the type of failure, risk evaluation of currently falling rocks requires further focus. The maximum movement distance of a rockfall in the simulation was approximately 66 m and the rockfall risk range was the entire area under slope. In addition, it is difficult to forecast where a rock will fall as it rolls in various directions due to topographic factors. Thus, the installation of measures to prevent falling is suggested to secure the stability based on the results of the rockfall simulations and its probabilistic analysis.

• Journal of the Society of Disaster Information
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• v.18 no.2
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• pp.252-260
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• 2022

Purpose: As the intensity and frequency of natural hazards are increasing due to climate change, external events that affecting nuclear power plants(NPPs) may increase. NPPs must be protected from external events such as natural hazards and human-induced hazards. External events that may occur in NPPs should be identified, and external events that may affect NPPs should be identified. This study introduces the methodology of identification and screening methods for external events by literature review. Method: The literature survey was conducted on the identification and screening methods of external events for probabilistic safety assessment of NPPs. In addition, the regulations on the identification and screening of external events were investigated. Result: In order to minimize the cost of external event impact analysis of nuclear power plants, research on identifying and screening external events is being conducted. In general, in the identification process, all events that can occur at the NPPs are identified. In the screening process, external events are selected based on qualitative and quantitative criteria in most studies. Conclusions: The process of identifying and screening external events affecting NPPs is becoming important. This paper, summarize on how to identify and screen external events for a probabilistic safety assessment of NPPs. It is judged that research on bounding analysis and conservative analysis methods performed in the quantitative screening process of external events is necessary.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.6
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• pp.101-111
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• 2008

Hangang Parks have been played an important role as the source of various Civilian activities by providing a natural space near Han River ever since it was developed. Due to the local-heavy rain caused by recent climate change, the Hangang Parks tends to be easily overflowed. Evacuation of the park in emergency and its controlled system should be made for the sake of Civilian's safety. In this study, various basic data and several parameters were analyzed to simulate the hydraulic effect of Hangang Parks based on the outflow in $P1/4{\div}1/4^3$ Dam. Rising effects of flood water level were investigated through the one-dimensional and twodimensional numerical hydraulic models. Relationships of water level and travel time of flood between key station and centeral part of each park were also identified. It can be used to forecast the future flood water level of each individual park in Hangang Parks. Obtained results can be used to establish the rational plan of usage, management, citizen's safety, and emergency action plan of the Hangang Parks as the flood is occurred from the outflow of Paldang dam.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.5
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• pp.71-76
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• 2008

The purposes of this study were to examine the coping behavior of the elderly in the warning phase of disaster and to explore factors influencing the coping behavior of the elderly. Data were collected from 130 senior citizens aged over 60 who are residing in Pyungchang and Injae of Kangwon province which had damaged by flood disaster in 2006. Perry & Lindell (1997)'s index, a series of six categories that represent coping behaviors which progressively approximate the action of evacuating in the warning phase of disasters was used. Results showed that respondents have high coping skills. Although Activities of Daily Living (ADL) has positive influence on the coping behavior, length of residence has negative effect on the coping behavior of the elderly. This finding proves the elderly are not uncompliant or uncooperative population in the warning phase of disaster. This result also emphasizes the importance of rapid and accurate giving of public warning system of disaster and necessity of prior notification of useful information about natural disaster and effective evacuation plan for the elderly.

• Journal of Environmental Health Sciences
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• v.46 no.1
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• pp.45-64
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• 2020

Objectives: Limited information is available on the presence and associated ecological risks of pharmaceutical residues in aquatic environments near pharmaceutical manufacturing areas in Korea. In this study, we investigated the current state of pharmaceutical contamination and its associated ecological risks in streams near a pharmaceutical manufacturing complex. Methods: Seven pharmaceuticals (acetaminophen, clarithromycin, diclofenac, diphenhydramine, ibuprofen, mefenamic acid and roxithromycin) were measured in water samples collected from the streams near a pharmaceutical manufacturing complex. A predicted no-effect concentration (PNEC) was derived using either the assessment factor method or species sensitivity distribution method. In addition, a hazard quotient for each pharmaceutical was calculated by dividing its measured environmental concentration by its PNEC. Results: Samples collected downstream from the wastewater treatment plant (WWTP) had higher concentrations of pharmaceuticals than those collected from the reference site (upstream). Moreover, pharmaceutical concentrations were greater in ambient water than in the final effluent from the WWTP, which suggested that non-point sources were contributing to the contamination of the ambient water environment. Some of the target pharmaceuticals exhibited a hazard quotient >1, indicating that their potential ecological effects on the aquatic environment near the pharmaceutical industrial area should not be ignored. Conclusion: This study demonstrated that the pharmaceutical manufacturing area was contaminated with residual drugs, and that there was a possible non-point source near the WWTP effluent discharge area. The results of this study will aid in the development of management plans for pharmaceuticals, particularly in hotspots such as pharmaceutical industrial sites and their vicinities.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.4
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• pp.11-20
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• 2009

By using the artificial lightweight aggregate for the natural aggregate depletes and destruction of environment and the application of lightweight concrete in structure, the lightweight concrete is manufactured. The fundamental characteristics by the waterbinder ratio was evaluated. It is suggested the method to control of pre-absorbed water of the lightweight aggregate. Lightweight concrete with pre-absorbed aggregate has similar characteristics compared to normal weight concrete regardless of water-binder ratio. According to the water-binder ratio, the drying condition, and the rebar, the unit mass of the lightweight concrete showed the reduction of 14.6${\sim}$21.0% as the range of 1,668${\sim}$1,998 $kg/m^3$ in comparison to the normal weight concrete. The lightweight aggregate pre-absorbed water showed the deferent evaporation quantity according to the water-binder ratio. As the water-binder ratio is lower, the oven dry vapour water is larger, therefore the internal curing water is increasing. In the same water-binder, comparing the normal concrete the lightweight concrete shows lower compressive strength which is due to the different strength of an aggregate. In the air dry curing, the normal weight concrete has a lower strength improvement effect in w/c 0.3 than the ratio 0.4 and 0.5. However, the strength improvement effect has increasing as the water-binder ratio was low in the light concrete.

• Proceedings of the KSRS Conference
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• 1999.11a
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• pp.148-153
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• 1999

Baikdu-san was a very active volcano during the Cenozoic era and is believed to be formed in late Cenozoic era. Recently it was also reported that there was a major eruption in or around 1002 A.D. and there are evidences which indicate that it is still an active volcano and a potential volcanic hazard. Remote sensing techniques have been widely used to monitor various natural hazards, including volcanic hazards. However, during an active volcanic eruption, volcanic ash can basically cover the sky and often blocks the solar radiation preventing any use of optical sensors. Synthetic aperture radar(SAR) is an ideal tool to monitor the volcanic activities and lava flows, because the wavelength of the microwave signal is considerably longer that the average volcanic ash particle size. In this study we have utilized several sets of SAR data to evaluate the utility of the space-borne SAR system. The data sets include JERS-1(L-band) SAR, and RADARSAT(C-band) data which included both standard mode and the ScanSAR mode data sets. We also utilized several sets of auxiliary data such as local geological maps and JERS-1 OPS data. The routine preprocessing and image processing steps were applied to these data sets before any attempts of classifying and mapping surface geological features. Although we computed sigma nought ($\sigma$$^{0}$) values far the standard mode RADARSAT data, the utility of sigma nought image was minimal in this study. Application of various types of classification algorithms to identify and map several stages of volcanic flows was not very successful. Although this research is still in progress, the following preliminary conclusions could be made: (1) sigma nought (RADARSAT standard mode data) and DN (JERS-1 SAR and RADARSAT ScanSAR data) have limited usefulness for distinguishing early basalt lava flows from late trachyte flows or later trachyte flows from the old basement granitic rocks around Baikdu-san volcano, (2) surface geological structure features such as several faults and volcanic lava flow channels can easily be identified and mapped, and (3) routine application of unsupervised classification methods cannot be used for mapping any types of surface lava flow patterns.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.5
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• pp.129-137
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• 2007

It is very urgent to research the proper recycling method of marine dredged soil as construction material for environmental conservation. Couple of developed countries have been lots of related researches on recycling of marine dredged soil for marine environmental conservation. This is highly imperative in our country. A small-scaled model test for underground pipe has been conducted on the use of controlled low strength materials with marine dredged soil. The flexible pipe, which is called PVC, was used. Four different testing materials, such as natural sand, insitu-soil, sand-CLSM with marine dredged soil and insitu-soil CLSM with marine dredged soil, were used. The vertical and lateral displacement of pipe with CLSM is one tenth of common granular materials. Also, the use of CSLM showed lower lateral and vertical pressure than that of common granular materials. The main reason is the effect of cement hardening of CLSM. This could increase of the stiffness of pipe with backfill materials. In this study, the data presented show that marine dredged soil and in-situ soil can be successfully used in CLSM and reduce the deformation and earth pressure on flexible pipe.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.5
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• pp.79-88
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• 2007

This study evaluated the statistical stationarity of rainfall quantiles as well as the rainfall itself. The conventional methodologies like the Cox-Stuart test for trend and Dickey-Fuller test for a unit root used for testing the stationarity of a time series were applied and evaluated their application to the rainfall quantiles. As results, first, no obvious increasing or decreasing trend was found for the rainfall in Seoul, which was also found to be a stationary time series based on the Dickey-Fuller test. However, the Cox-Stuart test for the rainfall quantiles show some trends but not in consistent ways of increasing or decreasing. Also, the Dickey-Fuller test for a unit root shows that the rainfall quantiles are non-stationary. This result is mainly due to the difference between the rainfall data and rainfall quantiles. That is, the rainfall is a random variable without any trend or non-stationarity. On the other hand, the rainfall quantiles are estimated by considering all the data to result in high correlation between their consecutive estimates. That is, as the rainfall quantiles are estimated by adding a stationary rainfall data continuously, it becomes possible for their consecutive estimates to become highly correlated. Thus, it is natural for the rainfall quantiles to be decided non-stationary if considering the methodology used in this study.