• Tunnel and Underground Space
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• v.27 no.5
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• pp.303-311
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• 2017

The correlation analysis between the results obtained from DFN flow model and equivalent continuum flow model were conducted on total of 72 DFN blocks having various fracture geometry and domain size. A strong linear relation seems to exist between the two approaches under condition that normalized relative error for continuum behavior (ER) is less than 0.2, and the results from both methods are found to almost identical. To explore the field applicability of equivalent continuum flow model in DFN media, a total of 48 numerical schemes related to inflow of underground circular openings were implemented under various DFN configurations. The equivalent continuum flow model in DFN media with a constant hydraulic aperture was evaluated as valid. However, as the anisotropy increases due to variation of the hydraulic aperture, the results are likely to be overestimated compare to the DFN flow model.

• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.703-711
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• 2009

This study was conducted to suggest to establish more effective and differential management strategy of arboretum, through the analysis and comparison between arboretum and representative forest recreational sites. The data was collected through questionnaire at the six fields of forest recreational sites in Daegu and Gyeongsangbuk-do, 447 people who visited these forest recreational sites took part in the questionnaire. As the result of this research, arboretum was positively evaluated by the six strengths from the participants; natural area, experiences and observation activity, conservation of natural environment, promotion of health, reasonable charge of use and a lot of things to see and do. But there is the need for arboretum to develop characteristic rest culture and raise efficiency because arboretum is in keen competition with recreation forests and national parks by several characteristics.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.2
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• pp.427-436
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• 2015

This study analyzes the factors effecting on pedestrian crossing behavior in the unsignalized intersection. Pedestrian crossing behavior is the results of mental stress defined as a combination of environment perception, avoiding accidents, halting collision, and instant crossing decision. It is necessary to make walkable intersection in cities through relieving this stress influenced by personality, traffic condition, and roadway environment. The purpose of study is empirically to examine the crossing behavior such as crossing satisfaction, crossing trial frequency and waiting time based on various factors effecting on crossing intersection by video and questionnaire survey. The $x^2$-test is applied to analyze the characteristics of crossing trial frequency according to each factor. Also, the hazard rate model is established to find the factors effecting on waiting time for crossing. Finally, the direct and indirect effects on the pedestrian crossing satisfaction are presented as the results of LISREL.

• Journal of Korean Society of Forest Science
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• v.83 no.3
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• pp.400-409
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• 1994

To investigate the noise attenuation effects of various vegetation configurations, noise levels on 6 study sites along relatively heavy traffic roads were measured. The differences between noise level measures at 1m and 10m spots from the road range from 10 to 15dB depending upon the attributes of the vegetation. When flat grass land was set to control plot, the maximum noise attenuation at 10m spot was measured at the densely planted shrubs with 5dB difference. The areas on upward slope from the road showed the least attenuation effects. Based on the study results, an appropriate setting for low level residential area noise buffer belt would be densely planted shrubs with at least 3m width and 2m height. To be effective, 3m width soft areas covered with grasses are needed at the front and behind sides of the belt. More than 15dB of the noise level caused by the road traffic would be attenuated with the prescription.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.8
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• pp.1452-1459
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• 2016

Compressed sensing is a signal processing technique for efficiently acquiring and reconstructing in and under Nyquist rate representation. Generally, the measurement prediction usually works well with a small block while the quality of recovery is known to be better with a large block. In order to overcome this dilemma, conventional research works use a structural measurement matrix with which compressed sensing is done in a small block size but recovery is performed in a large block size. In this way, both prediction and recovery are made to be improved at same time. However, the conventional researches did not compare the performances of the structural measurement matrix, affected by the block size. In this paper, by expanding a structural measurement matrix of conventional works, their performances are compared with different block sizes. Experimental results show that a structural measurement matrix with $4{\times}4$ Hadamard transform matrix provides superior performance in block size 4.

• Korean Journal of Construction Engineering and Management
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• v.16 no.3
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• pp.24-35
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• 2015

Aging educational facility shall be managed and maintained through integrated service perspectives, in consideration of functions of each facility to provide safe and comfortable environment, rather than temporarily fixing/repairing problems. For doing this, it is a must to firstly understand the limitation of highly biased performance-based maintenance practice, which is a most common type applied at present, and therefore to establish maintenance system that reflects the functions and characteristics of maintenance service that a facility was designed with. Therefore, the objective of this study is to find items that have an influence on service level recognition in order to fairly evaluate service functions of educational facilities, and subsequently to use these factors as ingredients of establishing a consistent and efficient maintenance system. Therefore this study proposed explanatory variables to measure influential factors for each major maintenance category. Then appropriate statistical verification was carried out on questionnaires that collected from a number of industry experts to test its fe asibility.

• Korean Journal of Cognitive Science
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• v.10 no.3
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• pp.39-49
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• 1999

The space of IID([ndependently, Identically Distributed) textures was built with axes of mean luminance and contrast, and studied on what kind of mechanisms were required to mediate texture segregation in this space. The conjecture was tested that one of these mechanisms is sensitive to the differences between the means of textures to be discriminated, whereas the other is sensitive to the differences between variances. The probability of discrimination was measured for various pairs of textures in the lID space The data were well fit by a model in which discrimination depends on two mechanisms whose responses are combined by probability summation. The conjecture was rejected that two mechanisms respectively tuned to mean and variance of texture function in segregation. Discrimination within space is mediated by 2 independent channels however: the 2 independent channels are not exactly tuned to texture mean and variance. One m mechanism was primarily sensitive to texture mean, whereas the other was sensitive to b both texture mean and variance.

• Korean Journal of Cognitive Science
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• v.21 no.4
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• pp.669-696
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• 2010

Assuming that the whole meaning of a document is a composition of the meanings of each part, this paper proposes to study the automatic grading of movie reviews which contain sentimental expressions. This will be accomplished by calculating the values of semantic segments and performing data classification for each review. The ARSSA(The Automatic Rating System for Sentiment analysis using an Appraisal dictionary) system is an effort to model decision making processes in a manner similar to that of the human mind. This aims to resolve the discontinuity between the numerical ranking and textual rationalization present in the binary structure of the current review rating system: {rate: review}. This model can be realized by performing analysis on the abstract menas extracted from each review. The performance of this system was experimentally calculated by performing a 10-fold Cross-Validation test of 1000 reviews obtained from the Naver Movie site. The system achieved an 85% F1 Score when compared to predefined values using a predefined appraisal dictionary.

• Journal of the Korean association of regional geographers
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• v.23 no.2
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• pp.288-310
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• 2017

This paper aims to provide a conceptual framework to see the special zones in East Asia in relation to the territorialities of the state. For this, it will introduce Aihwa Ong's notion of 'spaces of exception', and provide some critical discussions on it. Unlike Ong, I do not see the spaces of exception as an outcome of neoliberal changes of the state. Instead, I propose to see the special zones in terms of the internal limitations of the modern state territoriality. In particular, I try to theorize the special zones in relation to the dialectics of the contradictory relations between mobility and fixity inherent in the territoriality of the modern nation state. In addition, it will be suggested to see special zones as an essential part of the spatiality of the East Asian developmental states, given the spatio-temporal contexts of the East Asian capitalist development. On the basis of these theoretical discussions, this paper will divide the special zones that have been developed in East Asia since the 1960s into 3 different types, including 1) developmentalist special zones, 2) neo-liberal special zones, and 3) special zones for transition, and discuss their characteristics.

• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.4
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• pp.153-167
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• 2007

Dokdo research has been worked in various fields. However, the continuous accumulation and systematic management of Dokdo research data on marine science haven't been made. In particular, a systematic database system hasn't been established for the research data on marine environment and ecosystem in Dokdo and its surrounding sea. Therefore, GIS database construction on a spatial basis is required for the systematic management and efficient use of Dokdo marine research data, and a marine data model on a GIS basis is needed on the design stage to build the database. In this study, we collected previous observed marine data, and classified them as three groups, such as a framework data group on a GIS basis, a research data group and a thematic data group, according to the data types and characteristics. Moreover, the attributes of each research data were designed to be connected to GIS framework data. The result of the study to build an integrated GIS data model may be useful for developing a management system for marine research data observed in other sea as well as Dokdo.