• Journal of the Society of Disaster Information
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• v.17 no.2
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• pp.245-253
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• 2021

Purpose: This study develops a risk prediction model that predicts the risk of a fire site by using initial information such as building information and reporter acquisition information, and supports effective mobilization of fire fighting resources and the establishment of damage minimization strategies for appropriate responses in the early stages of a disaster. Method: In order to identify the variables related to the fire damage scale on the fire statistics data, a correlation analysis between variables was performed using a machine learning algorithm to examine predictability, and a learning data set was constructed through preprocessing such as data standardization and discretization. Using this, we tested a plurality of machine learning algorithms, which are evaluated as having high prediction accuracy, and developed a risk prediction model applying the algorithm with the highest accuracy. Result: As a result of the machine learning algorithm performance test, the accuracy of the random forest algorithm was the highest, and it was confirmed that the accuracy of the intermediate value was relatively high for the risk class. Conclusion: The accuracy of the prediction model was limited due to the bias of the damage scale data in the fire statistics, and data refinement by matching data and supplementing the missing values was necessary to improve the predictive model performance.

• Economic and Environmental Geology
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• v.55 no.1
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• pp.1-17
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• 2022

The mechanical and thermal properties of the rock masses can affect the performance associated with both the isolating and retarding capacities of radioactive materials within the deep geological disposal system for High-Level Radioactive Waste (HLW). In this study, the essential parameters for the site descriptive model (SDM) related to the rock mechanics and thermal properties of the HLW disposal facilities site were reviewed, and the technical background was explored through the cases of the preceding site descriptive models developed by SKB (Swedish Nuclear and Fuel Management Company), Sweden and Posiva, Finland. SKB and Posiva studied parameters essential for the investigation and evaluation of mechanical and thermal properties, and derived a rock mechanics site descriptive model for safety evaluation and construction of the HLW disposal facilities. The rock mechanics SDM includes the results obtained from investigation and evaluation of the strength and deformability of intact rocks, fractures, and fractured rock masses, as well as the geometry of large-scaled deformation zones, the small-scaled fracture network system, thermal properties of rocks, and the in situ stress distribution of the disposal site. In addition, the site descriptive model should provide the sensitivity analysis results for the input parameters, and present the results obtained from evaluation of uncertainty.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.3
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• pp.95-106
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• 2023

Korean healing research has developed over the past 20 years along with the growing social interest in healing. The field of healing research is diverse and includes legislated natural-based healing. In this study, abstracts of 2,202 academic journals, master's, and doctoral dissertations published in KCI and RISS were collected and analyzed. As for the research method, LDA topic modeling used to classify research topics, and time-series publication trends were examined. As a result of the study, it identified that the topic of Korean healing research was connected with 5 types and 4 mediators. The five were "Healing Tourism," "Mind and Art Healing," "Forest Therapy," "Healing Space," and "Youth Restoration and Healing," and the four mediators were "Forest," "Nature," "Culture", and "Education". In addition, only legalized healing studies extracted from Korean healing research and the topics were analyzed. As a result, legalized healing research classified into four. The four types were "Healing Spatial Environment Plan", "Healing Therapy Experiment", "Agricultural Education Experiential Healing", and "Healing Tourism Factor". Forest Therapy, which has the largest amount of research in legalized healing, Agro Healing and Garden Healing which operate similar programs through plants, and Marine Healing using marine resources also analyzed. As a result, topics that show the unique characteristics of individual healing studies and topics that are considered universal in all healing studies derived. This study is significant in that it identified the overall trend of research on Korean healing facilities and programs by utilizing LDA topic modeling.

• Journal of the Korean Society of International Agriculture
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• v.23 no.5
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• pp.560-569
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• 2011

In Japan, plant genomics research is mainly leaded by the national research institutes. The various structural studies such as rice genome has allowed researchers to analyze useful traits, and to focus their commercialization. With aims to facilitate structural and functional study in plant genome, NIAS (National Institute of Agrobiological Sciences) constructed Poaceae genome DB and RIKEN (Rikagaku Kenkyusho) built DB for Arabidopsis genome and plant full-length cDNA. NIG (National Institute of Genetics) constructed a national biological resources DB (National Bio Resource Project). This compiling DB provides a variety of genome-related research materials for researchers in the field. Recently, as an effort to resolve global issues of food supply and environmental problems, New Agri-genome Project has been performed aiming to develop an innovative agricultural technologies for the quantity, disease resistance and identifying useful genes related to environmental problems. In addition, in order to improve agricultural productivity in developing countries, JIRCAS assisted technical supports for the plant genome research and developed NERICA rice, which is suitable for African area. Such these approaches are expected to contribute to solving the global issues about food, energy and environment in the world.

• Asia Marketing Journal
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• v.15 no.2
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• pp.49-73
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• 2013

In this study, the author develops and tests a model that incorporates the mediating effects of two frontline employee psychological variables (emotional exhaustion and intrinsic motivation) based on job demand and resource model. As a form of environmental resource, person-organization fit was proposed as a leading factor of frontline employee boundary spanning behavior through emotional exhaustion and intrinsic motivation. All measures were adapted from or developed based on prior research. Data for the study were collected from a cross-sectional sample of retail bank employees in South Korea. Questionnaires were distributed to 500 frontline employees across several banks. Of these, 322 usable questionnaires were returned. To analyze the data, a structural equation model procedure using LISREL 8.5 was employed. Results show that an employee's perceived fit with his/her organization enhances intrinsic motivation and reduces emotional exhaustion. These mechanisms, in turn, increase the employee's boundary spanning behavior. These results support the notion that person-organization fit should be one of the factors affecting motivation, affect and attachment, and extends such an understanding to a purely service-based environment among customer contact employees. Results also confirms that P-O fit can be viewed as environmental resources, and the JD-R model provides a theoretical base in further studying the antecedent role of P-O fit on frontline employees's boundary spanning behavior through intrinsic motivation and emotional exhaustion. These results suggest that organizations have to do their best to manage P-O fit, be it through employee screening or training and workshops to try and align organization and employee values and objectives. If managers of organizations are positively evaluated by the employees, it will be easier for them to, give things of value to employees, such as sense of direction, values, and recognition, and receive other things in return such as esteem and responsiveness. Consequently, organizational leaders are not only able to manage employee experiences, but also their fit with the organization. Even if a manager cannot control employee P-O fit, this research suggests, that a focus on reducing emotional exhaustion rather than increasing intrinsic motivation seems optimal. This research also supports the idea that motivation has a direct association with a frontline employee's boundary spanning behavior. Even in situations where emotional exhaustion cannot be reduced, organizations may still influence frontline behaviors through motivation.

• Journal of Energy Engineering
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• v.16 no.2
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• pp.83-92
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• 2007

In view of stringent environment regulations to control the emission of green house gases and also depleting fossil fuel reserves, it is high quality desirable to develop alternative technologies to produce high quality fuels. To this end Biomass to Liquid (BTL) technology has received much attention in recent years. BTL process generally consists of gasification of biomass to produce bio-syngas, cleaning and control of $H_{2}/CO$ mole ratio of bio-syngas and Fischer-Tropsch synthesis & upgrading systems. Choren, Germany has first developed the commercial BTL process using unique gasification system i.e., Carbo-V. A new technology to remove tars and BTX has been developed by ECN in Netherlands employing a gasification system combined with OLGA technology. Several other countries including USA and Japan are showing great interest in BTL technology. Thus in view of our national energy security and also the environmental regulations, it is essential to develop alternative technologies like BTL in order to meet the increasing demand of energy though our insufficient biomass resources. In this paper we present an overview and development status of BTL-diesel technology.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.149-155
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• 2013

In this study, factors that affect the air entrainment within a closed conduit by air drawn in through an air vent are investigated using a hydraulic scale model, which represents a gated circular conduit system connected to the intake tower of an irrigation reservoir. In addition, using data obtained during the hydraulic experiments, experimental equations are developed to estimate the amount of air drawn in through the air vent. In case of pressurized flow conditions downstream of hydraulic jumps, the relationships between $\frac{Q_a}{Q_w}$ and $Fr_g-1$ of the data form a experimental equation, $\frac{Q_a}{Q_w}=0.0304(Fr_g-1)^{1.0622}$; in case of free surface flow conditions, $\frac{Q_a}{Q_w}=0.0271(Fr_g-1)^{1.8205}$. Comparing two data sets observed under the two flow regimes with the results of previous researchers, patterns of the data sets are similar to the results estimated using the equations presented previously, and this indicates that the quality of the data obtained during the hydraulic experiments is ensured. In addition, it is revealed that air entrainment phenomena in the regions close to air vents are affected by the characteristics of supercritical flows downstream of gates. Finally, it is concluded that the equation developed for pressurized flow conditions can be applied to design of air vents.

• Journal of Korean Society on Water Environment
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• v.26 no.5
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• pp.841-849
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• 2010

Soil erosion is an natural phenomenon. However accelerated soil erosion has caused many environmental problems. To reduce soil loss from a watershed, many management practices have been proposed worldwide. To develop proper and efficient soil erosion best management practices, soil erosion rates should be estimated spatially and temporarily. The Universal Soil Loss Equation (USLE) and USLE-based soil erosion and sediment modelling systems have been developed and tested in many countries. The Sediment Assessment Tool for Effective Erosion Control (SATEEC) system has been developed and enhanced to provide ease-of-use interface to the USLE users. However many researchers and decision makers have requested to enhance the SATEEC system for simulation of soil erosion and sediment reflecting effects of single storm event. Thus, the SATEEC R factors were estimated based on 5 day antecedent rainfall data. The SATEEC 2.1 daily R factor was applied to the study watershed and it was found that the R2 and EI values (0.776 and 0.776 for calibration and 0.927 and 0.911 for validation) with the daily R were greater than those (0.721 and 0.720 for calibration and 0.906 and 0.881 for validation) with monthly R, which was available in the SATEEC 2.0 system. As shown in this study, the SATEEC with daily R can be used to estimate soil erosion and sediment yield at a watershed scale with higher accuracy. Thus the SATEEC with daily R can be efficiently used to develop site-specific soil erosion best management practices based on spatial and temporal analysis of soil erosion and sediment yield at a daily-time step, which was not possible with USLE-based soil erosion modeling system.

• The Journal of Engineering Geology
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• v.20 no.3
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• pp.231-242
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• 2010

In order to assess applicability of debris flow simulation on natural terrain in Korea, this study introduced the DEBRIS-2D program which had been developed by Liu and Huang (2006). For simulation of large debris flows composed of fine and coarse materials, DEBRIS-2D was developed using the constitutive relation proposed by Julien and Lan (1991). Based on the theory of DEBRIS-2D, this study selected a valley where a large debris flow was occurred on July 16th, 2006 at Deoksanri, Inje county, Korea. The simulation results show that all mass were already flowed into the stream at 10 minutes after starting. In 10minutes, the debris flow reached the first geological turn and an open area, resulting in slow velocity and changing its flow direction. After that, debris flow started accelerating again and it reached the village after 40 minutes. The maximum velocity is rather low between 1 m/sec and 2 m/sec. This is the reason why debris flow took 50 minutes to reach the village. The depth change of debris flow shows enormous effect of the valley shape. The simulated result is very similar to what happened in the field. It means that DEBRIS-2D program can be applied to the geologic and topographic conditions in Korea without large modification of analysis algorithm. However, it is necessary to determine optimal reference values of Korean geologic and topographic properties for more reliable simulation of debris flows.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3B
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• pp.293-303
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• 2011

An efficient diagonalized approximate factorization algorithm (DAF) is developed for the solution of three-dimensional incompressible viscous flows. The pressure-based, artificial compressibility (AC) method is used for calculating steady incompressible Navier-Stokes equations. The AC form of the governing equations is discretized in space using a second-order-accurate finite volume method. The present DAF method is applied to derive a second-order accurate splitting of the discrete system of equations. The primary objective of this study is to investigate the computational efficiency of the present DAF method. The solutions of the DAF method are evaluated relative to those of well-known four-stage Runge-Kutta (RK4) method for fully developed and developing laminar flows in curved square ducts and a laminar flow in a cavity. While converged solutions obtained by DAF and RK4 methods on the same computational meshes are essentially identical because of employing the same discrete schemes in space, both algorithms shows significant discrepancy in the computing efficiency. The results reveal that the DAF method requires substantially at least two times less computational time than RK4 to solve all applied flow fields. The increase in computational efficiency of the DAF methods is achieved with no increase in computational resources and coding complexity.