• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.138-144
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• 2013

Large and small marine accidents which are related to vessel's navigation are happening continuously and these maritime accidents have caused loss of lives and properties, and serious maritime environmental pollution damage. It is also true that maritime pollution damage is increasing due to these accidents, probability of growth of seaborne volume and complicated maritime traffic environment. Korea, recently, is developing an evaluation index which can assess sea risk through the evaluation of maritime traffic environment and provide danger and general information with relation to maritime traffic environment on target sea area to evaluate maritime traffic safety. In this paper, we intend to confirm the validity of maritime traffic safety on the basis of vessel navigator's risk consciousness and various sailing conditions by using the ship handling simulator. To confirm the validity of sailing vessel's maritime traffic safety, we use analysis of variance. By using analysis of variance, we analyze vessel navigator's characteristics, distance, speed and encounter type between vessels. Through multiple comparison of each factor's risk difference, we can confirm the change of numerical value of risk difference in statistical aspect.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.1
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• pp.159-172
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• 2014

As greenhouse gas emissions have been increasing in the world, global warming is being recognized as a cause of the global problems like climate change. This is closely associated the fossil fuels. Thus renewable energy has been brought to the attention of many people as the upcoming alternative energy source to cope with the fossil drain and increased environmental regulations. Especially, the solar energy among renewable energy has drastically increased. In this study, we calculate on daylight ratio about the solar energy for buildings based on digital surface model. The digital surface model was made using the spatial information data. And it was simulated the shadow analysis using SAS. Therefore, it was suitable places to utilize the solar energy in the Gyeongsan city. Consequently, the daylight ratio was considered important factor to select region of the industry of the solar light power generation.

• Journal of the Korea Institute of Building Construction
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• v.10 no.4
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• pp.49-57
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• 2010

Selecting an appropriate formwork to fit the construction of a high-rise building is an important factor that can influence the success or failure of a construction. Currently, however, the reality is that in domestic high-rise building construction, the selection of an appropriate formwork with consideration of the characteristics of the formwork has not been done in a reasonable manner. To select formwork in a systematic and reasonable fashion, comprehensive consideration is required that must not only include the aspect of construction costs, but also air, quality, safety, and environmental issues. Therefore, this study aims to rationalize the selection process of formwork by applying the scientific method of Analytic Hierarchy Process (AHP) to the selection process of formwork, in terms of construction costs, quality and safety. To do this, the researcher investigated the current status of formwork being used in high-rise residential building construction. Then, based on the results of this investigation, the researcher selected an alternative for the formwork, and taking construction experts as the subjects of this study, conducted a survey on the applicability of the formwork as well as the priority of management thereof when selecting formwork. It is judged that the results of this research will contribute a more scientific and reasonable decision-making process than the existing non-scientific method in selecting formwork for high-rise residential building construction.

• Journal of Food Hygiene and Safety
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• v.16 no.2
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• pp.103-110
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• 2001

Predictive food microbiology(PFM) is an emerging area of food microbiology since the later 1980’s. It does apply mathematical models to predict the responses of microorganism to specified environmental variables. Although, at present, PFM models do not completely developed, models can provide very useful information for microbiological responses in HACCP(Hazard Analysis Critical Control Point) system and Risk Assessment. This study illustrates the possible use of PFM models(PMP: Pathogen Modeling Program win5.1) with milk in several elements in the HACCP system, such as conduction of hazard analysis and determination of CCP(Critical Control Points) and CL(Critical Limits). The factors likely to affect the growth of the pathogens in milk involved storage fixed factors were pH 6.7, Aw 0.993 and NaCl 1.3%. PMPwin5.1 calculated generation time, lag phase duration, time to level of infective dose for pathogens across a range of storage (Critical Control Points) and CL(Critical Limits). The factors likely to affect the growth of the pathogens in milk involved storage temperature, pH, Aw and NaCl content. The factors likely to affect the growth of the pathogens in milk involved storage temperature, pH, Aw and NaCl content. The variable factor was storage temperature at the range of 4~15$^{\circ}C$ and the fixed factors were pH 6.7, Aw 0.993 and NaC 1.3%. PMPwin5.1 calculated generation time, lag phase duration, time to level of infective dose for pathogens across a range of storage temperature.

• Culinary science and hospitality research
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• v.17 no.3
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• pp.20-32
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• 2011

The purpose of this study is to analyze customers' behavior in using word-of-mouth(WOM) information about Korean local food restaurants. The questionnaire developed for this study was distributed to 500 customers living in Jeonbuk area and a total of 455 copies (91.0%) were used for analysis. The statistical analysis was conducted using SPSS Win(12.0). The results were summarized as follows. The recommendation of people experienced'($M=3.57{\pm}1.24$) and 'word-of-mouth through people around'($M=3.52{\pm}1.20$) were major word-of-mouth information sources of Korean local foods; 'taste of food'($M=4.16{\pm}1.15$) and 'service quality'($M=3.79{\pm}1.11$) were important attributes in word-of-mouth information. In addition, to the question about the reasons for recommending the restaurant to the people around, the most people replied that 'flavor, nutrition and quality of local foods can be kept only in the specific location' ($3.53{\pm}1.08$), followed by 'to keep the memory of the visit to the areas in mind through local foods'($3.51{\pm}1.03$). These results showed that people usually recommend a restaurant based on the quality of the food itself or local characteristics. As a result, it is deemed that word-of-mouth effect is an important factor for the spread of Korean local foods.

• Journal of Bio-Environment Control
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• v.13 no.4
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• pp.209-216
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• 2004

This study was aimed to assess the effects of microclimate factors on lettuce chlorophyll fluorescent responses and to develop an environment control system for plant growth by adopting a simple genetic algorithm. The photosynthetic responses measurements were repeated by changing one factor among six climatic factors at a time. The maximum Fv'/Fm' resulted when the ambient temperature was $21^{\circ}C,\;CO_2$ concentration range of 1,200 to 1,400 ppm, relative humidity of $68\%$, air current speed of $1.4m{\cdot}s^{-1}$, and the temperature of nutrient solution of $20^{\circ}C$. In PPF greater than $140{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, Fv'/Fm' values were decreased. To estimate the effects of combined microclimate factors on plant growth, a photosynthesis efficiency model was developed using principle component analysis for six microclimate factors. Predicted Fv'/Fm' values showed a good agreement to measured ones with an average error of $2.5\%$. In this study, a simple genetic algorithm was applied to the photosynthesis efficiency model for optimal environmental condition for lettuce growth. Air emperature of $22^{\circ}C$, root zone temperature of $19^{\circ}C,\;CO_2$ concentration of 1,400 ppm, air current speed of $1.0m{\cdot}s^{-1}$, PPF of $430{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, and relative humidity of $65\%$ were obtained. It is feasible to control plant environment optimally in response to microclimate changes by using photosynthesis efficiency model combined with genetic algorithm.

• The Korean Journal of Pesticide Science
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• v.10 no.2
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• pp.91-98
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• 2006

The objective of this study was to compare dioxin contents in spinach, soil and air and to evaluate the relation of dioxin concentrations in crop and its cultural environment. Sample weighing for the precise peak detection in dioxin analysis was also determined. The fragmentogram of HpCDFs, and especially OCDF, indicated different pattern from that of TeCDD/F, PeCDD/Fs and HxCDDs/Fs, which showed the same pattern. In case of field culture spinach (wet sample 2 kg) in Japan, peak of OCDF could be detected clearly, while market spinach (wet sample 1 kg) showed the only baseline detection. The result makes it possible to suppose the fact that production place of market spinach was not contaminated with OCDF, but atmospheric pattern of production place was similar to that of open field sample. So we could decide that the sample of agricultural crops were needed more than 2 kg in wet weight for the evaluation of precise peak The total tendency of dioxin concentration levels in field culture spinach may be affected by OCDD and HCDF distributed in soil. However, on the whole the major factor seems to be the atmospheric deposition.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.1
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• pp.83-97
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• 2018

Tunnels are widely used for special purposes including roads, railways and culvert for power transmission, etc. Its cross-section shape is determined by uses, ground condition, environmental or economic factor. Many papers with respect to behaviours of adjacent ground and existing structure tunnelling-induced have been published by many researchers, but tunnel cross-section have rarely been considered. A collapse of tunnel causes vaster human and property damage than structures on the ground. Thus, it is very important to understand and analyse the relationship between behavoiurs of ground and cross-section type of tunnel. In this study, the behaviour of ground due to tunnel excavation for underground station below the grouped pile supported existing structure was analysed through laboratory model test using a trap-door device. Not only two cross-section types, 2-arch and box, as station for tunnel, but also, offset between tunnel and grouped pile centre (0.1B, 0.25B, 0.4B) are considered as variable of this study. In order to measure underground deformation tunnelling-induced, Close Range Photogrammetry technique was applied with laboratory model test, and results are compared to numerical analysis.

• Journal of the Korean Geographical Society
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• v.50 no.3
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• pp.355-373
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• 2015

In this study the factors of fire damage are analyzed through previous research reviews. Local environmental factors as well as those factors attributed to fire damage (number of fire events, number of injured, number of death, economic loss) were selected to compose mutual relationship model. In order to verify this relationship model, official statistics concerning fire damage were collected from 228 local governments and compared with results from previous research. As a result of this comparison four dependent variables and 22 independent variables that affect fire damage were analyzed. Independent variables are divided into human vulnerability factors, physical vulnerability factors, economic vulnerability factors, mitigating factors and local characteristics. To analyze a relationship between selected dependent variables and independent variables, we applied a semi-logarithm model and performed regression analysis. Among the 22 independent variables, the number of the weak to disaster, social welfare service workers, workers in manufacturing industry, and the number of workers in restaurants and bars per 10,000 people show the significant correlation with the number of fire incidence. The number of death from fire is significantly related to two variables which are the number of social welfare service workers per 10,000 and the ratio of commercial area. Damage cost is significantly dependent on the property taxes per 10,000 people. These factors were included in the research model as vulnerability factors (human, physical, economic) and mitigating factors and local characteristics, and the validity of research model was verified. The result could contribute to fire-fighting resource allocation in Korea or they can be utilized in establishing fire prevention policy, which will enhance the national level of fire safety.

• Journal of Bio-Environment Control
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• v.23 no.1
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• pp.11-18
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• 2014

To investigate the influence of surrounding environment on the plant temperature and examine the effect of plant temperature control by fogging and airflow, plant temperature of tomato, inside and outside air temperature and relative humidity, solar radiation and wind speed were measured and analyzed under various experimental conditions in plastic greenhouse with two-fluid fogging systems and air circulation fans. According to the analysis of plant temperature and the change of inside and outside air temperature in each condition, inside air temperature and plant temperature were significantly higher than outside air temperature in the control and shading condition. However, in the fogging condition, inside air temperature was lower or slightly higher than outside air temperature. It showed that plant temperature could be kept with the temperature similar to or lower than inside air temperature in fogging and airflow condition. To derive the relationship between surrounding environmental factor and plant temperature, we did multiple regression analysis. The optimum regression equation for the temperature difference between plant and air included solar radiation, wind speed and vapor pressure deficit and RMS error was $0.8^{\circ}C$. To investigate whether the fogging and airflow contribute to reduce high temperature stress of plant, photosynthetic rate of tomato leaf was measured under the experimental conditions. Photosynthetic rate was the highest when using both fogging and airflow, and then fogging, airflow and lastly the control. So, we could assume that fogging and airflow can make better effect of plant temperature control to reduce high temperature stress of plant which can increase photosynthetic rate. It showed that the temperature difference between plant and air was highly affected by surrounding environment. Also, we could estimate plant temperature by measuring the surrounding environment, and use it for environment control to reduce the high temperature stress of plant. In addition, by using fogging and airflow, we can decrease temperature difference between plant and air, increase photosynthetic rate, and make proper environment for plants. We could conclude that both fogging and airflow are effective to reduce the high temperature stress of plant.