• Journal of the Korean earth science society
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• v.35 no.4
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• pp.225-236
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• 2014

Multivariate statistical analyses have been extensively applied to hydrochemical measurements to analyze and interpret the data. This study examines anthropogenic factors obtained from applications of correspondence analysis (CA) and principal component analysis (PCA) to a hydrogeochemical data set. The goal was to synthesize the hydrogeochemical information using these multivariate statistical techniques by incorporating hydrogeochemical speciation results calculated by the program, commonly used, WATEQ4F included in the NETPATH. The selected case study was LPG underground storage caverns, which is located in the southeastern Korea. The highly alkaline groundwaters at this study area are an analogue for the repository system. High pH, speciation of Al and possible precipitation of calcite characterize these groundwaters. Available groundwater quality monitoring data were used to confirm these statistical models. The present study focused on understanding the hydrogeochemical attributes and establishing the changes of phase when two anthropogenic effects (i.e., disinfection activity and cement pore water) in the study area have been introduced. Comparisons made between two statistical results presented and the findings of previous investigations highlight the descriptive capabilities of PCA using calculated saturation index and CA as exploratory tools in hydrogeochemical research.

• Science of Emotion and Sensibility
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• v.15 no.4
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• pp.585-592
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• 2012

Food is crucial for the nutrition and survival of humans. Taste system is one of the fundamental senses. Taste cells detect and respond to five basic taste modalities (sweet, bitter, salty, sour, and umami). However, the cortical processing of taste sensation is much less understood. Recently, there were many efforts to observe the brain activation in response to taste stimulation using functional magnetic resonance imaging (fMRI), magnetoencephalography (MEG), and optical imaging. These different techniques do not provide directly comparable data each other, but the complementary investigations with those techniques allowed the description and understanding of the sequence of events with the dynamics of the spatiotemporal pattern of activation in the brain in response to taste stimulation. The purpose of this study is the understanding of the brain activities to taste stimuli in sensory and affective aspects and the reviewing of the recent research of the gustotopic map by functional brain mapping.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.6
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• pp.562-570
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• 2009

An Experimental study was conducted on the flow characteristics and interference heating caused by a two-dimensional object protruding from a flat plate using a blow-down type of hypersonic wind tunnel. Inflow condition was a free-stream Mach number of 7.0 and a unit Reynolds number of $2.0{\times}10^6/m$. Experimental conditions were varied with three heights of protuberance for two flat plate models which have different lengths. Experimental data were obtained from Schlieren visualization images and heat flux measurements. Also, this paper suggests hypersonic experimental techniques such as boundary-layer detection method in detail. A Large separation region was observed in front of the protuberance and that region was very sensitive to the height of protuberance and the length of the flat plate. For only the highest protuberance, a severe jump of heat flux was observed at the top station among the measuring points. Measured heat flux is large when the height of protuberance is large and the length of flat plate is long.

• Journal of the Korean Geosynthetics Society
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• v.20 no.4
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• pp.33-41
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• 2021

Feldspar, along with Quartz, are the most frequently produced minerals in Korea; however, the potential value is estimated to be significantly low because of the scarce research on the development and application of material properties, except for their limited use in manufacturing minerals, glass, and paints. In this study, we analyzed the eco-friendly material and reactivity improvement characteristics of weathered feldspar through activation technique. The joint structural features observed on the surface of the weathered feldspar show that the joint arrangements are irregularly distributed, and the cavities are interconnected. Due to the irregularly connected cavities on the surface of weathered feldspar, the reaction area of the weathered feldspar is increased; hence the weathered feldspar is considered as a highly reactive pozzolan material when combined with cement. As a result of applying the thermal, mechanical, and chemical activation techniques to improve the functionality of the weathered feldspar, the cation exchange capacity, density, and uniaxial compression strength characteristics were improved. It is considered that weathered feldspar by these porous characteristics can be used as an eco-friendly construction material with excellent physical and chemical properties.

• The Journal of the Acoustical Society of Korea
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• v.24 no.1
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• pp.58-68
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• 2005

In this paper, we propose a scheme to improve discriminative property in the feature compensation method for robust speech recognition under noisy environments. The estimation of noisy speech model used in existing feature compensation methods do not guarantee the computation of posterior probabilities which discriminate reliably among the Gaussian components. Estimation of Posterior probabilities is a crucial step in determining the discriminative factor of the Gaussian models, which in turn determines the intelligibility of the restored speech signals. The proposed scheme employs minimum classification error (MCE) training for estimating the parameters of the noisy speech model. For applying the MCE training, we propose to identify and determine the 'competing components' that are expected to affect the discriminative ability. The proposed method is applied to feature compensation based on parallel combined mixture model (PCMM). The performance is examined over Aurora 2.0 database and over the speech recorded inside a car during real driving conditions. The experimental results show improved recognition performance in both simulated environments and real-life conditions. The result verifies the effectiveness of the proposed scheme for increasing the performance of robust speech recognition systems.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.6A
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• pp.537-543
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• 2007

In this paper, we propose a new stopping criterion for the turbo processing (Turbo-BLAST) of MIMO-OFDM system. To reduce the high computational complexity of turbo-BLAST, it is desirable to lessen the outer-loop iteration number. In a system such as IEEE 802.16e Mobile WiMax, no CRC bits are available except the last encoding packet of a transmitted burst, so early stopping criteria without the help of CRC bits are needed. The proposed criterion counts the sign differences between received parity bits and the re-encoded parity bits from received information bits. With the tail-biting code which is accepted for IEEE 802.16e, a method that the re-encoder operates at half complexity is also proposed. Computer simulations show that the proposed stopping criterion approaches the performance of GENIE aided criterion with less average number of iterations than the other early stopping criteria.

• Korean Journal of Culture and Social Issue
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• v.19 no.3
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• pp.487-506
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• 2013

The present study investigated whether do the efforts of interviewer really impact on the building a rapport by using four rapport building techniques-personalization, empathy, listening, and credibility. One woman probation officer interviewed 139 criminals(male, 122; female, 17). And she tried to building a rapport by using 4 rapport building techniques for about 11 minutes in every interview. In result, the degree of rapport perceived by interviewees was different significantly between high rapport group and low rapport group of 4 each rapport technique. Result suggests that personalization and listening techniques would be efficient way of building a rapport in investigative interviewing.

• Journal of Korean Tunnelling and Underground Space Association
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• v.14 no.4
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• pp.357-374
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• 2012

Considerable uncertainties are included in ground properties used for tunnel designs due to the limited investigation and tests. In this study, a back analysis was performed to find optimal ground properties based on artificial neural network using both face mapping data and convergence measurement data. First of all, the rock class of a study tunnel is determined from face mapping data. Then the possible ranges of ground properties were selected for each rock class through a literature review on the previous studies and utilized to establish more precise learning data. To find an optimal training model, a sensitivity analysis was also conducted by varying the number of hidden layers and the number of nodes more minutely than the previous study. As a result of this study, more accurate ground properties could be obtained. Therefore it was confirmed that the accuracy of the results could be increased by making use of not only convergence measurement data but also face mapping data in tunnel back analyses using artificial neural network. In future, it is expected that the methodology suggested in this study can be used to estimate ground properties more precisely.

• The KIPS Transactions:PartD
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• v.12D no.3 s.99
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• pp.345-354
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• 2005

Subsequence matching is one of the most important operations in the field of data mining. The existing subsequence matching algorithms use only one index, and their performance gets worse as the difference between the length of a query sequence and the site of windows, which are subsequences of a same length extracted from data sequences to construct the index, increases. In this paper, we propose a new subsequence matching method based on index interpolation to overcome such a problem. An index interpolation method constructs two or more indexes, and performs search ing by selecting the most appropriate index among them according to the given query sequence length. In this paper, we first examine the performance trend with the difference between the query sequence length and the window size through preliminary experiments, and formulate a search cost model that reflects the distribution of query sequence lengths in the view point of the physical database design. Next, we propose a new subsequence matching method based on the index interpolation to improve search performance. We also present an algorithm based on the search cost formula mentioned above to construct optimal indexes to get better search performance. Finally, we verify the superiority of the proposed method through a series of experiments using real and synthesized data sets.

• Conservation Science in Museum
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• v.29
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• pp.153-162
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• 2023

Clay figure of Baekje, produced by forming and molding various shapes using clay, are mainly excavated from temple sites and provide essential information for studying the Buddhist art of Baekje. Research on clay figures of Baekje primarily focuses on the characteristics of Baekje-era temples in which such figures are excavated, as well as the role and production techniques of clay figures, by comparing regional and morphological characteristics. In particular, research on the manufacturing method of clay figures is mainly carried out by visual observation, whereas precise scientific analysis is required to understand production techniques and characteristics of raw materials in greater detail. In this study, to confirm such production techniques and material characteristics, computed tomography (CT) scans were conducted on the Clay Bodhisattva excavated from the Neungsan-ri Temple site in Buyeo. As a result, it was found that the Clay Bodhisattva was made using a cylindrical core of fine clay, tied together with several thin branches or reeds with straws. The clay used in the figure bore traces indicating the presence of herbaceous plants, which increase adhesion between clay and prevent cracks in the contraction process. On the other hand, the density of the fine clay differs on the inside and outside of the clay figure. Based on this, it is presumed that the clay was applied around the cylindrical core to shape the Clay Bodhisattva. The clay was reapplied on top of the figure to express the detailed shape and pattern.