• Journal of Korean Society of Transportation
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• v.29 no.3
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• pp.123-137
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• 2011

In general, flow propagation has been explained using the shock wave theory which is expressed as a function of variations in volume and density. However, the theory has certain limitation in portraying heterogeneous flow, e.g., flow propagation between lanes. Motivated by this fact, this study seeks a new measure for analyzing the propagation characteristics of traffic flow at three sections of highway (i.e., merging area, weaving section, and basic section) from temporal and spatial perspectives, and then develops a model for estimating the measure for the flow propagation. The "shock wave speed" which is the measure widely adopted in literature, was first applied to describe the propagation characteristics, but it was hard to find distinct characteristics in the propagation. This finding inspires to develop a new measure named "Impulse Volume". It is shown that the measure better explains the propagation characteristics at the three study sections of highway. In addition, several models are also developed by performing multi-regression analyses to explain the flow propagation between lanes. The models proposed in this paper can be distinguished in three sections and the lane placement.

• Journal of the Korean Chemical Society
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• v.42 no.6
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• pp.599-606
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• 1998

Since the discovery of ceramic superconductor the various theoretical developments has progressed but there are no definitive description about the superconducting transition mechanism. In special, both the double transition and the various magnetic phase transition add to the complication of the understanding of HTSC. In this paper, we presented the idea of the two-step mechanism for the superconducting transition in view of the condensation model of electron fluid for superconductivity. And these concepts are successfully applied to the double transition and the magnetic phase diagram of various types of superconductivity. Therefore, both the double transition and magnetic phase transition should be the touchstone of general theory for superconductivity.

• Korean Journal of Logic
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• v.8 no.2
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• pp.33-58
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• 2005

The old evidence problem raises a profound problem to Bayesian theory of confirmation that evidence known prior to a hypothesis explaining it cannot give any empirical support to the hypothesis. The old evidence problem has resisted to a lot of trials to solve it. The purpose of the paper is to solve the old evidence problem by showing that the problem originated from a serious misunderstanding about the Bayesian concept of confirmation. First, I shall make a brief analysis of the problem, and examine critically two typical Bayesian strategies to solve it. Second, I shah point out a misunderstanding commonly found among Bayesian discussions about the old evidence problem, the ignorance of the asymmetry of confirmation in the context of explanation and prediction. Lastly, 1 shall suggest two different concepts of confirmations by using the asymmetry and argue that the concept of confirmation presupposed in the old evidence problem is not a genuine Bayesian concept of confirmation.

• Journal of the Korean Geographical Society
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• v.48 no.1
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• pp.72-86
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• 2013

Industrial agglomeration is an old theme in economic geography and many studies have been devoted to this topic. But only few have empirically looked at the time trend of industrial agglomeration. This study measured agglomeration of U.S. industries over last 29 years and measurement results indicated that industrial clustering has occurred during the study period in all study industries without a common time trend shared amongst the study industries. The agglomeration levels then were plugged in to investigate causalities, i.e. causal relations, around industrial agglomeration. Three variables were selected to see causal relations with agglomeration levels based on literatures, and our focus was given to the causality between transport network and agglomeration. Causal relation from transport to agglomeration was found in various industries and this supports the argument that the development of transportation influences industrial agglomeration. At the same time inverse and bi-directional causalities were also revealed implying more complex relationship between these two.

• Journal of the Korea Concrete Institute
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• v.26 no.3
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• pp.343-350
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• 2014

A probabilistic construction stage analysis using the Monte Carlo Simulation was performed to address the effects of uncertainty regarding the material properties, environmental factors, and applied forces. In the previous research, creep and shrinkage were assumed to be completely independent random variables. However, because of the common influencing factors in the material models for the creep and shrinkage estimation, strong correlation between creep and shrinkage can be presumed. In this paper, an Monte Carlo Simulation using CEB-FIB creep and shrinkage equations were performed to actually evaluate the correlation coefficient between two phenomena, and then another Monte Carlo Simulation to evaluate the statistical properties of axial strain affected by partially correlated random variables including the material properties, environmental factors, and applied forces. The results of Monte Carlo Simulation were compared with measured strains of a column on a first story in a 58-story building. Comparison indicated that the variation due to the uncertainty related with the material properties were most severe. And measured strains was within the range of mean+standard deviation.

• Journal of Korean Home Economics Education Association
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• v.15 no.3
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• pp.59-73
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• 2003

This study aims to review and analyze the contents related to environment among curriculum of Technology$.$Home Economics subject; to produce multimedia learning materials and web-based materials for effective environmental education: and to find the way to effectively utilize them in schools. The data were analyzed by t-test with SPSS Win 10.0 program. The results of this study are as follows; First, the textbook carries a lot of contents concerning the environment. Second, the multimedia materials help students to understand environmental issues and strengthen their attitudes of environmental problems very effectively. Third, after using the instructional multimedia materials, the students showed significantly different results.

• The Journal of the Korea Contents Association
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• v.16 no.3
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• pp.553-562
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• 2016

Then, it investigated the investment preference through the previous studies to analyze the influence factor of investment satisfaction and demonstrated the effects through the PLS (Partial Least Squares) regression. In addition, it separated the target type to institutional investors and retail investors and carried out the survey for comparing the investment preference of investor type. The result of analysis found out that institutional investors emphasis on investment preference such as the Inflation hedge, Early payback, Financial stability, Leverage risk and etc. Then, general investors emphasis on investment preference such as the Rental income, Facilities and Equipment, Business area and population, Ease of use, Leverage risk, Early payback and etc. In addition, common investment preferences are the Leverage risk, Early payback and Facility accessibility.

• The KIPS Transactions:PartC
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• v.11C no.3
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• pp.353-360
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• 2004

In this Paper, We propose an efficient iteration decoding control method with variable iteration decoding of iteration codes decoding using Cyclic Redundancy Check. As the number of iterations increases, the bit error rate and frame error rate of the decoder decrease and the incremental improvement gradually diminishes. However, when the iteration decoding number is increased, it require much delay and amount of processing time for decoding. Also, It can be observed the error nor that the performance cannot be improved even though increasing of the number of iterations and SNR. So, Suitable number of iterations for stopping criterion is required. we propose variable iteration control method to adapt variation of channel using Frame Error-Check indicator. Therefore, the amount of computation and the number of iterations required for iteration decoding with CRC method can be reduced without sacrificing performance.

• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.6
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• pp.505-510
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• 2013

In order to detect and identify the GPS clock anomaly in the Differential GPS real environment, this paper addresses a method for minimizing the measurement noise of reference receivers. It estimates the real measurement noise that removed the uncommon error source from pseudorange measurement to minimize the measurement noise. Based on the output of two reference receivers, it first removes the uncommon errors, then optimizes the measurement noise by applying the correction data. Finally, it detects and identifies the satellite clock anomaly using the minimized measurement noise. The method will increase the availability of current DGPS reference system.

• Journal of the Korean Geographical Society
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• v.47 no.6
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• pp.975-992
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• 2012

This study analyzed the citation count of papers and authors in the field of human geography through the multidimensional scaling and social network analysis with the papers and their references published in Journal of Korean Geographical Society(Geography). The major findings of this study are as follows. Group formation of common approaches in intelligent network has not formed by cited literature in the field of human geography of a journal representing Korea. Then, each researcher should study consistently on a subject to form a school rather than diversify the field and subject of study. They also need to increase the citation count by accumulating research work with a high degree of completion. In addition, many universities with a lot of enrolled graduate students of master's and doctorate course have a responsibility to encourage the formation of school. Meanwhile, if the master's and doctoral dissertations are not official publications unlike journals, the citation of them should be avoided institutionally because it is the unique phenomena of Korea.