• Science of Emotion and Sensibility
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• v.9 no.1
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• pp.27-38
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• 2006

In the planning stage of mobile phone development, one of the most important considerations is to select a FormFactor properly to determine the strategy and Purpose of a Product. Up to now, the FormFactor has been selected only by intuitional and qualitative methods. In this study, the Appraisal Methodology using Sensibility Adjectives of Emotion and Sensibility Engineering was presented to suggest the systematic and rational framework in the field of FormFactor selection. First, we verified the conceptual FormFactors with Axiomatic Design and classified the Sensibility Adjectives into the verified FormFactors. When the FormFactor and classified Design Parameters (DP) were given to a designer, the designer implemented the preliminary designs and they were assessed and analyzed by the survey. With these processes, we were able to select the proper designs for FormFactors which were fit for the purpose of a product. This was caused by connecting the Axiomatic Design and tile Sensibility Adjectives. This study gave the possibilities that can be spread to the selection factors, except for the FormFactor, from now on.

• Journal of Navigation and Port Research
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• v.42 no.6
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• pp.539-545
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• 2018

In recent years, research on shipping market forecasting with the employment of non-linear AI models has attracted significant interest. In previous studies, input variables were selected with reference to past papers or by relying on the intuitions of the researchers. This paper attempts to address this issue by applying the stepwise regression model and the random forest model to the Cape-size bulk carrier market. The Cape market was selected due to the simplicity of its supply and demand structure. The preliminary selection of the determinants resulted in 16 variables. In the next stage, 8 features from the stepwise regression model and 10 features from the random forest model were screened as important determinants. The chosen variables were used to test both models. Based on the analysis of the models, it was observed that the random forest model outperforms the stepwise regression model. This research is significant because it provides a scientific basis which can be used to find the determinants in shipping market forecasting, and utilize a machine-learning model in the process. The results of this research can be used to enhance the decisions of chartering desks by offering a guideline for market analysis.

• Journal of Korean Society of societal Security
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• v.2 no.1
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• pp.65-74
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• 2009

In this study, the air pollution management system based GIS has been developed to estimate the emission rate and air pollution modeling of air pollutants, effectively. This system is able to estimate emission rate of air pollutant and to analyze the emission characteristics with high spatial and temporal resolution. air pollution modeling. The air pollution management system was applied to Gwangyang Bay including large industry complex with a large number of emission sources. The air pollution management system was constructed using the spatial database of emission sources in Gwangyang Bay. It was found that the estimated emission rates of air pollutants is similar to the emission characteristics in Gwangyang Bay. Also, the spatial distribution of pollutants was similar to the location of emission sources. The predicted results of air pollution model was showed a good correlation coefficient (0.75) for TSP. The air pollution management system is expected to be effective tool (database system (GIS)) for the management and the control of air pollution.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.4
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• pp.117-123
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• 2013

The purpose of this research is to suggest the reasonable method of Network RTK surveying in future cadastral re-survey project through the accuracy analysis about Network RTK surveying achievement and the conventional TS-based confirmation surveying. To achieve it, we selected the experiment places and succeeded in achieving the result by Network RTK surveying about total of 307 parcel boundary point. We compared it with the result of confirmation surveying for cadastral, and it was shown that total connection errors of RMSE was ${\pm}0.1028m$ and total 48 places exceeded in the cadastral re-survey allowable error tolerance. The research suggested the practical alternatives in cadastral re-survey project after the comprehensive evaluation of those analysis results. Therefore, the author suggested development and adoptation of integrated electronic plane table surveying method. Moreover, we suggested unifying the first parcel boundary point method into the total station surveying and adopt the Network RTK surveying on the cadastral surveying inspection.

• Journal of the Korean Geosynthetics Society
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• v.18 no.4
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• pp.139-149
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• 2019

For retaining wall designs, horizontal earth pressure induced by traffic loads over the walls is calculated based on equivalent uniform pressure height. The AASHTO LRFD design standards propose equivalent uniform pressure height of traffic loads; however, the equivalent uniform pressure height is calibrated using the US standard trucks. As the domestic standard trucks are different from the US standard trucks, in this study, new domestic equivalent uniform pressure height is proposed using the Boussinesq theory varying vehicle directions, Poisson's ratios of pavement layers, and retaining wall height. The proposed equivalent uniform pressure heights are generally higher than those proposed by the AASHTO design standards because the axle loads and their densities of two domestic standard trucks are higher than those of the US standard trucks. The most highest equivalent uniform pressure height was found for traffic direction perpendicular to longitudinal direction of retaining wall.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.1
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• pp.69-76
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• 2020

Bridges which are components of road network consume large amounts of resources such as concrete and steel materials, which have large environmental impacts during construction. This causes a great environmental burden. In order to reduce the environmental impact caused by the construction of the bridge, the environmental impact should be reviewed based on reasonable data in the early design stage. The purpose of this study is to provide basic data for LCA-based environmental impact assessment in the process of selecting bridge type in the early design stage. For this purpose, design data for four types of PSC bridges (general PSC girder, IPC girder, e-Beam, DR girder) were collected and LCA was performed to analyze the basic unit value and impact factors of environmental load. The results of the analysis showed that the environmental impact of IPC girder was the smallest, and the environmental impact of e-Beam was 133.7% higher than that of IPC girder. In addition, concrete, reinforcement, PC strand, square timber, sheath pipe, and steel plate were derived as the main factors that generate 98.5% of the overall environmental impact of PSC girder.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.1
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• pp.57-70
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• 2017

In this study, we investigated the wear measurement methods for slurry pipe applied in the field of mining and oil sand industry and theoretical equations related to the prediction of wear in slurry pipe through literature review. Average daily wear rate and wear rate per excavated distance were determined from slurry discharge pipe thickness measurement data periodically measured at the actual slurry shield TBM site in Singapore. The wear rate of slurry pipe for Bukit Timah Granite was obtained. The wear rates for G (V) grade and mixed zone were 1.5 times higher than that of G (I) to G (IV) grade. Slurry pipe wear rate tends to increase in proportion to the slurry discharge velocity. The optimal slurry pipe replacement or rotation frequency can be estimated through the selection of the pipe wear rate considering geological condition and the reasonable pipe management thickness.

• Journal of the Korea Convergence Society
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• v.8 no.2
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• pp.53-62
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• 2017

This study was to find the factors influencing satisfaction of Korean medical tour services of Chinese college students. Structured questionnaire was developed to collect data. The data were collected from the 175 students between May 1 and May 15 in 2015 in an international college in China. The expectations and the evaluations on the Korean medical tour services were compare by t-test. To find the factors influencing satisfaction on Korean medical tour services, diverse linear regression models were estimated. According to the best fit regression model, technologies, quality of medical tour services, and health care cost significantly and positively influenced satisfaction on the Korean medical tour services. The results of the study suggested that we need to prepare marketing strategies to improve understandings on Korean medical tour services for the Chinese college students. Improvement of technology, improvement of quality of health service, and setting of reasonable price are important to attract more Chinese patients to Korea.

• Journal of the Korean Geosynthetics Society
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• v.16 no.4
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• pp.241-249
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• 2017

In a reinforced soil structure, the interaction between soil and an reinforcement occurs due to the frictional resistance on the contact surface between them or the pullout resistance of the reinforcement. Generally, a pullout test is conducted to measure pullout parameters of extensible geogrids. The factors affecting the pullout parameters in a pullout test include a density of backfill, shape of reinforcements, overburden pressure, length of spread reinforcements, and so on. The purpose of this study is to suggest a length of the spreading of an extensible reinforcement that can be used in estimating suitable pullout parameters of a pullout test. To this end, a pullout test was carried out. For the test, the length of spreading of an extensible reinforcement was set as 32 cm, 52 cm, 72 cm, and 100 cm, and effects of the lengths on pullout parameters were analyzed. As a result of the pullout test, it was confirmed that the frictional resistance between the soil and the reinforcement increases with the increase of the length of the reinforcement.

• Journal of the Korea Concrete Institute
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• v.23 no.4
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• pp.495-501
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• 2011

The load combinations in current KCI Design Code are determined with reference to those in ACI 318-05, which adopts the LRFD (load and resistance factor design) format. The load and resistance factors in LRFD format should be determined to meet the required levels of reliability index or probability of failure for various predetermined failure modes, which are also based on the statistical data reflecting locality and contemporary situation. However, the current KCI Design Code has been written utilizing foreign data, because of insufficiency in accrued data in Korea. This study considered the current safety levels of KCI Code based on published domestic data to evaluate appropriateness of the current KCI regulations. Based on the calibrated reliability index of the existing Code, the new resistance factors are suggested. The results presented in this paper can be considered as a basic research for establishment of unique design format for future Korean Codes.