• Tunnel and Underground Space
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• v.12 no.1
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• pp.10-18
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• 2002

Rock joint system makes a heavy effect on the behavior of rock structures. The definition of a 3D rock joint system is very important in 2D or 3D numerical analysis for the prediction of the behavior of a discontinuous rock mass. To enhance the reality of a 3D definition of rock joint system, it is essential to estimate the unbiased statistics of basic geometric attributes of rock joints. In this study, we have proposed the statistical analysis and derived the related equations for an estimation of statistics of joint size and intensity. Geometry of rock joints in 3 dimensional space can be defined by the aggregate of location, size, orientation and intensity. The dimensional limit of survey method and its data makes 3D geometric attributes probabilistic. In the estimation of statistics of joint size, we have discussed the technique to correct the bias from a dimensional limit and derived the equation of 3D joint intensity by stereological approaches.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.1
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• pp.1-8
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• 2013

This study will not only prove experimental dynamic properties which are classified to slump, compressive strength, tensile strength, flexure strength and toughness granite soil concrete with a fine aggregate of granite soil and blast-furnace cement and polypropylene fiber over 45 mm, but also establish a basic data in order to use environment-friendly pavement through prove useful pavement mixed with granite and polypropylene (PP) fiber which is a kind of material to prevent a dry shrinkage clack, a partial destruction and useful and light. The value of slump test was gradually increased by PP fiber volume 3 $kgf/m^3$, but compressive strength took a sudden turn for the worse from 5 $kgf/m^3$. The compressive strength indicated a range of 13.72~18.35 MPa. On the contrary to compressive strength, the tensile strength showed to decrease with rising PP fiber volume, and the tensile strength indicated a range of 1.43~1.64 MPa. The tensile strength was stronger about 2~15 % in case of mixing with PP fiber volume than normal concrete. The flexural strength indicated a range of 2.76~3.41 MPa. The flexural strength was stronger about 20 % in case of PP fiber volume 0 $kg/m^3$ than PP fiber volume 9 $kg/m^3$. The toughness indicated a range of 0~25.46 $N{\cdot}mm$ and increased proportionally with PP fiber volume. The toughness was stronger about 8.3 times in case of PP fiber volume 9 $kg/m^3$ than PP fiber volume 1 $kg/m^3$. The pavement with PP fiber volume over such a fixed quantity in the park roads and walkways can have a effect to prevent not only resistance against clack but also rip off failures.

• Journal of Korea Technology Innovation Society
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• v.9 no.2
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• pp.199-235
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• 2006

Research interest in TQM has recently begun extending beyond manufacturing to moreinnovative R&D activities. Despite numerous studies of the relationship between TQM and organizational performance, little are known about the relationship between TQM and R&D performance. This is especially true for manufacturing-based R&D performance. The objective of this study is to examine the relationship between TQM and R&D, and also explore several contingencies that moderate the relationship. The study uses data from 133 R&D divisions of Korean manufacturing firms to test hypotheses regarding the relation of TQM with R&D. TQM measures are aligned with the six criteria of Malcolm Baldrige National Quality Award, and the R&D performance measures consist of incremental and innovative R&D aspects. The findings from structural equation modeling show that TQM practices contribute to R&D performance significantly in aggregate, and their specific contributions vary according to the contingencies, which provide further understanding of the relationship between TQM and R&D in the manufacturing sector. Therefore, the results could offer firms a better strategy for their R&D management. This study is, however, exploratory in nature; the conclusion is tentative and may thus be different in other research settings.

• Journal of Korea Technology Innovation Society
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• v.16 no.1
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• pp.20-40
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• 2013

A project of developing marine environmental risk assesment and management technology was proposed to improve the level of marine environmental management research. This paper attempts to measure the non-market benefits of the project. To this end, the dichotomous choice contingent valuation method is used. In particular, recently proposed one and one-half bounded model is applied. The model can reduce the potential for response bias comparing to the double bounded model while maintaining much of its efficiency. Moreover, in order to deal with zero WTP observations, a spike model is adjusted for our data. A survey of randomly selected 600 households was implemented and the respondents were asked in person-to-person interviews about how they would be willing to pay for implementing the project. Respondents overall accepted the contingent market and were willing to contribute a significant amount (2,663 won), on average, per household per year. The aggregate value of the project in the nation amounts to approximately 46.3 billion won per year. The figure 2.16 of cost-benefit ratio shows that economic validity of this technical development.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5865-5872
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• 2011

Multi-hop communication in clustering system is the technique that forms the cluster to aggregate the sensing data and transmit them to base station through midway cluster head. Cluster head around base station send more packet than that of far from base station. Because of this hot spot problem occurs and cluster head around base station increases energy consumption. In this paper, I propose a cluster group head selection using trajectory clustering technique(CHST). CHST select cluster head and group head using trajectory clustering technique and fitness function and it increases the energy efficiency. Hot spot problem can be solved by selection of cluster group with multi layer and balanced energy consumption using it's fitness function. I also show that proposed CHST is better than previous clustering method at the point of network energy efficiency.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.1 no.2
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• pp.85-92
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• 2000

Warrants are often described as call potions written tv firms on their own stock. However, a call option is a pure side bet; i.e., none of the cash flows associated with the call's sale or exercise involves the firm. Issuing warrants on the other hand, can affect the firm's aggregate level of investment, composition of its capital structure. and the price of the stock on which warrant can be exercised. The problem of the warrant pricing can be solved by using of multivariate data analysis techniques, such as regression analysis or discriminant analysis, instead of OPM. The value of this approach is that we can evlauate the relative importance of each independent variable which affect a price of a warrant. This study empirically examines the Japanese warrant pricing by multiple regression analysis using a sample or 300 observations traded on Tokyo Stock Exchange during the periods between 1995 and 1996.

• Journal of Distribution Science
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• v.15 no.1
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• pp.71-81
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• 2017

Purpose - Consumers heuristically have a specific stereotype on the price level of individual retail format because each format provides them with a different level of purchase satisfaction and emotional benefits. However, if price image which is consumers' overall impression of the aggregate price level of a retailer does not match with their expectations, its price level would be perceived as unfair. It will eventually lead to dissatisfaction and decreased revisit intention. Focused on department store and discount store, this study was designed to verify whether the price fairness plays a role of mediating effect on two influential relationships between price image and post-purchase satisfaction, and price image and repatronage intention. Research design, data, and methodology - A main survey was conducted to 140 students and 128 effective responses were used for the related analysis. T-test, factor analysis, reliability test, and mediated regression analysis were performed. Six hypotheses were developed to examine the mediating effect of price fairness on the two influential relationships between price image and post-purchase satisfaction, and price image and repatronage intention. It was also examined whether the price image of two different retail format is formed differently or not. Results - People perceived the price images of the two retail formats differently. Overall price level of department store is much higher than that of discount store. Analysis results showed that price image did not solely have a significant influence on post-purchase satisfaction unless price fairness as a mediating variable is added. Price fairness turned out to be having a significant influence on relationship between price image and repatronage intention. It influences on repatronage intention directly and also via price fairness. Conclusions - Post-purchase satisfaction can be achieved only if people perceive the price image as fair no matter how the price level is high or low according to traits of retail formats. If they think it's not fair, they would disapprove of the rightness for the price image, and also express their dissatisfaction with it. Consumers willingly make repeated visits to a store if they are convinced of appropriate price level which is perceived as fair, and if they experienced a satisfaction with overall benefits a particular store offered.

• The Korean Journal of Applied Statistics
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• v.29 no.3
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• pp.525-537
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• 2016

The paper considers a hybrid model to analyze and forecast time series data based on an empirical mode decomposition (EMD) that accommodates complex characteristics of time series such as nonstationarity and nonlinearity. We aggregate IMFs using the concept of cumulative energy to improve the interpretability of intrinsic mode functions (IMFs) from EMD. We forecast aggregated IMFs and residue with a hybrid model that combines the ARIMA model and an exponential smoothing method (ETS). The proposed method is applied to forecast KOSPI time series and is compared to traditional forecast models. Aggregated IMFs and residue provide a convenience to interpret the short, medium and long term dynamics of the KOSPI. It is also observed that the hybrid model with ARIMA and ETS is superior to traditional and other types of hybrid models.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.4
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• pp.478-483
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• 2010

This study was conducted to investigate the physico-chemical properties of Schizandra chinensis Baillon orchard soils located in Jangsu-gun, Jeollabuk-do. Surface (0 to 10 cm) soils were collected from 200 experimental sites located at Jangsu-eup (53 site), Gyenam-myeon (31), Chunchun-myeon (73), Janggye-myeon (12), Bunyam-myeon (31). The soil texture was mostly loamy sand, and the mean values of degree of soil aggregate and soil porosity were 33.1 and 59.9%, respectively. The pH, EC, total-N, available-P, soil organic matter, and cation exchange capacity of the soils were $5.51{\pm}0.54$, $290{\pm}139{\mu}S\;cm^{-1}$, $946.3{\pm}65.5mg\;kg^{-1}$, $319.6{\pm}29.2mg\;kg^{-1}$, $29.0{\pm}13.9g\;kg^{-1}$ and $4.11{\pm}0.34cmol_c\;kg^{-1}$, respectively. The concentrations of Pb, Cd, Cu and Zn were $3.48{\pm}0.55$, $0.09{\pm}0.04$, $6.90{\pm}0.91$ and $97.7{\pm}42.2mg\;kg^{-1}$, respectively. The presented data can be utilized in better managing Schizandra chinensis Baillon orchard soils in the studied areas.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.6
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• pp.35-43
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• 2010

This study was carried out to find reliable relations between various concrete strength properties which are used as input data in concrete pavement design program. Concretes were made from different sources of coarse grained(granite, limestone and sandstone) and fine grained aggregates such as natural sand, washed sand and crushed sand. From strength test results, model equations were obtained based on the relation between strengths. For each coarse grained aggregate, models for compression-flexural strengths, compression-split tensile strengths, compressive strength-modulus and flexural-split tensile strengths with age were obtained. For concrete mixed with gneiss granite aggregates, concrete strengths were obtained from numerical mean values of concrete strengths mixed with fine grained aggregates. In addition models for concrete split tensile strengths and modulus values were provide by averaging numerically the estimated values obtained from the derived relationship and the experimental values. This is due to more scattered values of split tensile strengths and modulus values than other strength properties. Finally criteria for drying shrinkage strain as well as Poisson's ratio for concrete used in pavement were presented for all mixes with differed coarse grained aggregates.