• Structural Engineering and Mechanics
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• 제42권1호
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• pp.121-129
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• 2012

All contemporary seismic Codes have adopted smooth design acceleration response spectra, which have derived by statistical analysis of many elastic response spectra of natural accelerograms. The above smooth design spectra are characterized by two main branches, an horizontal branch that is 2.5 times higher than the peak ground acceleration, and a declining parabolic branch. According to Eurocode EN/1998, the period range of the horizontal, flat branch is extended from 0.1 s, for rock soils, up to 0.8 s for softer ones. However, from many natural recorded accelerograms of important earthquakes, the real spectral amplification factor appears to be much higher than 2.5 and this means that the spectrum leads to an unsafe seismic design of the structures. This point is an issue open to question and it is the object of the present study. In the present paper, the spectral amplification factor of the smooth design acceleration spectra is re-calculated on the grounds of a known "reliability index" for a desired probability of exceedance. As a pilot scheme, the seismic area of Greece is chosen, as it is the most seismically hazardous area in Europe. The accelerograms of the 82 most important earthquakes, which have occurred in Greece during the last 38 years, are used. The soil categories are taken into account according to EN/1998. The results that have been concluded from these data are compared with the results obtained from other strong earthquakes reported in the World literature.

• 여성건강간호학회지
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• 제25권1호
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• pp.31-45
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• 2019

Purpose: This study was designed to develop a valid and reliable scale for the evaluation of preconception health behavior in women preparing for pregnancy. Methods: The initial strategy included a literature review, interviews, and construction of a conceptual framework. The preliminary items were evaluated twice for content validity by experts, and modified two preliminary investigations. Participants in the 2 main investigations and the confirmation investigation were tested for reliability and validity of the preliminary scale in women preparing for pregnancy. The data were analyzed for different items exploratory and confirmatory factors. Results: The 5-point Likert scale consisted of 6 factors and 27 items. The 6-factors included 'hazardous substance factor,' 'medical management factor,' 'rest and sleep factor,' 'stress management factor,' 'information acquisition factor,' and 'resource preparation factor.' Goodness of fit of the final research model was very appropriate and based on the following measures: Q=1.98, comparative fit index=.91, Tucker-lewis index=.89, standardized root mean square residual=.07, and root mean square error of approximation=.07. The criterion validity was .64. The reliability coefficient was .92 and the test-retest reliability was .61. Conclusion: The study findings indicate that the scale can be used for the development of nursing interventions to promote preconception health behavior in women preparing for pregnancy.

• Geomechanics and Engineering
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• 제30권6호
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• pp.551-564
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• 2022

Fragmenting the rock mass is considered as the most important work in open-pit mines. Ground vibration is the most hazardous issue of blasting which can cause critical damage to the surrounding structures. This paper focuses on developing an explicit model to predict the ground vibration through an multi objective evolutionary polynomial regression (MOGA-EPR). To this end, a database including 79 sets of data related to a quarry site in Malaysia were used. In addition, a gene expression programming (GEP) model and several empirical equations were employed to predict ground vibration, and their performances were then compared with the MOGA-EPR model using the mean absolute error (MAE), root mean square error (RMSE), mean (𝜇), standard deviation of the mean (𝜎), coefficient of determination (R²) and a20-index. Comparing the results, it was found that the MOGA-EPR model predicted the ground vibration more precisely than the GEP model and the empirical equations, where the MOGA-EPR scored lower MAE and RMSE, 𝜇 and 𝜎 closer to the optimum value, and higher R² and a20-index. Accordingly, the proposed MOGA-EPR model can be introduced as a useful method to predict ground vibration and has the capacity to be generalized to predict other blasting effects.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.310-313
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• 2004

The aim of this study is to evaluate the hazard of landslides at Penang, Malaysia, using a Geographic Information System (GIS) and remote sensing. Landslide locations were identified in the study area from interpretation of aerial photographs and from field surveys. Topographical and geological data and satellite images were collected, processed, and constructed into a spatial database using GIS and image processing. The factors chosen that influence landslide occurrence were: topographic slope, topographic aspect, topographic curvature and distance from drainage, all from the topographic database; lithology and distance from lineament, taken from the geologic database; land use from TM satellite images; and the vegetation index value from SPOT satellite images. Landslide hazardous area were analysed and mapped using the landslide-occurrence factors by logistic regression model. The results of the analysis were verified using the landslide location data and compared with probabilistic model. The validation results showed that the logistic regression model is better prediction accuracy than probabilistic model.

• 대한임상독성학회지
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• 제3권1호
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• pp.11-16
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• 2005

Chemical mixtures of components, each of which are present at less than guidance concentrations, may be hazardous due to additivity, interactions, or both. Toxicological interactions may increase the health hazard above what would be expected from an assessment of each component singly, or all components additively. So chemical mixture are a particular issue in public health. There are several approach to assess whether there are additivity or interaction in assessing toxicological effects, such as, components-based approach, physiologically-based pharmacokinetic /pharmacodynamic(PBPK/PD) models, hazard index method, and weight-of evidence method. If we consider interaction or additivity effects in assessing the health effects of chemcial mixtures, we can get more accurate information about toxicological effects and dose-response relationship in chemical mixtures.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2011년도 춘계학술논문발표회 논문집
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• pp.155-159
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• 2011

건축법에서 건축마감재료의 연소독성은 설치류(마우스)를 사용한 가스유해성시험으로 평가되고 있다. 최근 동물시험에 대한 최소화 및 대체시험개발의 필요성으로 인해 연소가스의 정량분석을 통한 독성지수연구가 요구되고 있다. 본 연구에서는 이미 철도차량에서 적용되고 있는 BS6853의 연소독성평가를 통해 기존 가스유해성시험결과의 상대적인 비교분석을 수행하여, 건축재료의 연소독성평가에 대한 다양한 가능성을 제시하고자 하였다.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2013년 추계학술대회
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• pp.275-290
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• 2013

The main cause of building fire fatalities occur in the combustible material heat, smoke and toxic gases are. Building interior decoration, etc., especially as much of the harmful substances generated during combustion, and, used in domestic architecture wallpaper, ceiling, and other plastics, built-in foam insulation also analyzed recognition of fire hazards approach to test the conkalrorimiteo test, choedaeyeolbangchulryul through, chongbal heat, mass loss rate, generates carbon monoxide gas hazard ratio tests, analysis and evaluation rigid foam index testing the toxicity of hazardous material generated by performing a gas clean up and assess the material test results, the minimum order to provide data to quantify the risk of fire. Ensure fire safety of building materials, composite materials in order to test the various risk factors could be considered organic to the introduction of testing and evaluation is needed urgently.

• 한국안전학회지
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• 제10권2호
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• pp.92-96
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• 1995

The flash point is generally used as a hazardous index of fire or explosion of a flammable liquid. In this study, the lower flash points and the upper flash points according to the composition of Toluene-o-Xylene and Toluene-Methyl Ethyl Ketone mixtures are determined by air-blowing method. As results, relations between the flash points and the compositions of mixtures ; (1) for Toluene-o-Xylene mixtures $T_{fL}$=25.23 $\alpha$ ＋5.34 $T_{fu}$=27.36 $\alpha$ ＋40.50 (2) for Toluene-Methyl Ethyl Keton mixtures $T_{fL}$=10.00 $\beta$-5.00 $T_{fu}$=16.91 $\beta$＋20.45.

• 한국안전학회지
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• 제15권3호
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• pp.78-82
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• 2000

The flash point is an important property and hazardous index of a flammable liquid. The flash points are used by virtually all the environmental, health, and safety organizations in both government and industry to classify flammable liquids for safety and transportation regulations. The basics of all flash points behavior are concerned with the vapor pressure and explosive limits. The flash points of pure components and the mixture of solvents can be calculated with the use of the laws of Raoult, Dalton and Le Chatelier. In this paper, experimentally determined lower flash points of a p-xylene and epoxy resin system were compared with the calculated values by using Raoults law. Calculated lower flash points were in reasonable agreement with the observed values.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.129-131
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• 2003

The aim of this study is to evaluate the hazard of landslides at Penang, Malaysia, using a Geographic Information System (GIS) and remote sensing. Landslide locations were identified in the study area from interpretation of aerial photographs and field surveys. The topographic and geologic data and satellite image were collected, processed and constructed into a spatial database using GIS and image processing. The used factors that influence landslide occurrence are topographic slope, topographic aspect topographic curv ature and distance from drainage from topographic database, geology and distance from lineament from the geologic database, land use from TM satellite image and vegetation index value from SPOT satellite image. Landslide hazardous area were analysed and mapped using the landslide-occurrence factors by probability - likelihood ratio - method. The results of the analysis were verified using the landslide location data. The validation results showed satisfactory agreement between the hazard map and the existing data on landslide location.