• The Journal of the Petrological Society of Korea
• /
• v.17 no.4
• /
• pp.206-221
• /
• 2008

We have studied general orientational characteristics of microcracks distributed in Bulgugsa Granites of southwestern Gyeongsang Basin. Microcracks of 131 sets, which were developed on horizontal surfaces of II rock samples collected from Sacheon-Gosung, Geoje-si and Namhae-gun areas, were distinguished by image processing. Then, 45 sets with a distinct linear array on image were sorted out. These microcracks can be comparable with vertical grain planes. Orientations of these microcracks were compared with those of vertical rift and grain planes developed in Cretaceous and Jurassic granites of Korea. In the distribution chart, the agreement of the distribution pattern between microcracks of 45 sets and above vertical planes suggests that microcrack systems developed all over the study area also occur regionally in Cretaceous and Jurassic granites of Korea. Whole domain of the directional angle-frequency chart can be divided into 20 domains in terms of the phases of the distribution of microcracks. Meanwhile, 18 domains from 45 sets of microcracks were compared with the maximum principal stress orientations suggested from previous studies. The majority of maximum principal stress orientations pertain to domain $1{\sim}2$, $5{\sim}6$, $11{\sim}15$, $17{\sim}18$ and $19{\sim}20$, and these domains are coincident with the orientation of the 1st and 2nd-frequency orders represented in a rose diagram for 45 sets of microcracks. Representative orientations of open microcrack reflect the maximum principal stress orientations suggested in previous studies.

• Tunnel and Underground Space
• /
• v.25 no.5
• /
• pp.450-461
• /
• 2015

Extensive numerical experiments have been carried out to investigate effect of block size and fracture geometry on hydraulic characteristics of fractured rock masses based on connected pipe flow in DFN systems. Using two fracture sets, a total of 72 2-D fracture configurations were generated with different combinations of fracture size distribution and deterministic fracture density. The directional block conductivity including the theoretical block conductivity, principal conductivity tensor and average block conductivity for each generated fracture network system were calculated using the 2-D equivalent pipe network method. There exist significant effects of block size, orientation, density and size of fractures in a fractured rock mass on its hydraulic behavior. We have been further verified that it is more difficult to reach the REV size for the fluid flow network with decreasing intersection angle of two fracture sets, fracture plane density and fracture size distribution.

• Korean Institute of Interior Design Journal
• /
• v.23 no.3
• /
• pp.48-55
• /
• 2014

Luis Barragan is a representative Mexican architect. He designed architectural space as a local architect in consideration of the Mexico's harsh Mediterranean climate. His manifestation of the regionality can be found mainly in his precise expression of light. Such method and concept of using light in Barragan's architecture made a huge impact on later architects but detailed studies on this issue have not been made actively. Hence, this paper intended to suggest a starting point or an orientation by illustrating the characteristics of using and expressing light in architecture through his cases of housing works. The study method was as follows. First, the general characteristics of light were identified by analyzing the elements of architectural space that dealt with light and the characteristics of expressing light shown in the architectural space. Second, the architectural background of Luis Barragan and the architectural space elements of the light expressed in his architectural space were extracted to form a hypothetical ground. Third, five of his works on the houses in his prime (after the year of 1945) were analyzed to explore the characteristics of relational representation between light and the architectural space elements in his architecture. Through this process, it was learned that, in his architectural works, light was the embodiment of the location-related, time-based, daily and illusionary experience into architecture. In addition, meditative light could be experienced by contrasting the soft and dispersed light and shadow of the inside space of Barragan's houses with the strong external light. Therefore, through the process above, this study is hoped to provide an opportunity for the contemporary architects of our era to rethink the fundamental correlation between architecture and light.

• Tunnel and Underground Space
• /
• v.8 no.3
• /
• pp.226-233
• /
• 1998

Microcracks in rock materials, whether natural or induced, provide useful information on the engineering performance of in situ rockmasses. A population of preferentially oriented microcracks has observable effects on the physical properties of a rockmass, but their effects may not be evident if the rock material is highly anisotropic due to other causes. An experimental program was undertaken to investigate the effect of rock fabrics on the physical properties of rock materials. In this study, anisotropy in the circumferential wave velocity and the direction of induced fractures under axial point loading were measured. Rock specimens (NX-size) of the leucocractic Pocheon granite were cored from rock blocks, retaining the relative directions of each specimen. Another set of specimens was prepared from the rock cores of the same meterial, obtained in the field. The master orientation line (MOL) was set to be the representative direction of the microcracks in the specimen. Variation of the circumferential wave velocity of each specimen was then measured along the core, keeping the MOL as reference. The direction of the minimum wave velocity was nearly perpendicular to the direction of the MOL. Coring of smaller-sized (EX-size), concentric specimens from the NX specimens were then followed, and axial point loading was applied. The direction of induced fractures due to axial point loading was closely related to the MOL direction, confirming the prior test result.

• Tunnel and Underground Space
• /
• v.19 no.2
• /
• pp.158-166
• /
• 2009

As a basic study for investigating the development of the stress-induced crack in Hoek-Brown rock, a homogenization technique of elastic cracks is proposed. The onset of crack is monitored by Hoek-Brown empirical criterion, while the orientation of the crack is determined by the critical plane approach. The concept of volume averaging in stress and strain component was invoked to homogenize the representative rock volume which consists of intact rock and cracks. The formulation results in the constitutive relations for the homogenized equivalent anisotropic material. The homogenization model was implemented in the standard FEM code COSMOSM. The numerical uniaxial tests were performed under plane strain condition to check the validity of the propose numerical model. The effect of friction between the loading plate and the rock sample on the mode of deformation and fracturing was examined by assuming two different contact conditions. The numerical simulation revealed that the homogenized model is able to capture the salient features of deformation and fracturing which are observed commonly in the uniaxial compression test.

• Korean Journal of Food Science and Technology
• /
• v.14 no.1
• /
• pp.21-29
• /
• 1982

The texture describing terms used for the Korean staple foods, cooked rice, noodles and Kimchi, were surveryed by questionnaire. A total of 154 kinds of terms were collected from 68 answers, in which 95 words were found with definite textural meaning in Korean dictionaries. The terms were classified according to their physical properties by Szczesniak's method. The important textural properties of different types of Korean foods were pointed out by the frequency of mentioning and by the preference expressions. The representative Korean words expressing each textural property of different types of food were selected. The important textural properties for Korean were hardness, brittle-gumminess, chewiness, springiness, adhesiveness, particle size and shape, moisture content and fat content of cooked rice, chewiness, hardness, springiness, and particle size and shape of noodles, and hardness, brittle-gumminess, chewiness, springiness and particle shape and orientation of Kimchi.

• Journal of the Optical Society of Korea
• /
• v.12 no.2
• /
• pp.98-102
• /
• 2008

Optical Coherence Tomography (OCT) is an important noninvasive medical imaging technique that can reveal subsurface structures of biological tissue. OCT has demonstrated a good correlation with histology in sufficient resolution to identify morphological changes in articular cartilage to differentiate normal through progressive stages of degenerative joint disease. Current OCT systems provide individual cross-sectional images that are representative of the tissue directly under the scanning beam, but they may not fully demonstrate the degree of degeneration occurring within a region of a joint surface. For a full understanding of the nature and degree of cartilage degeneration within a joint, multiple OCT images must be obtained and an overall assessment of the joint surmised from multiple individual images. This study presents frequency domain three-dimensional (3-D) OCT imaging of degenerative joint cartilage extracted from bovine knees. The 3-D OCT imaging of articular cartilage enables the assembly of 126 individual, adjacent, rapid scanned OCT images into a full 3-D image representation of the tissue scanned, or these may be viewed in a progression of successive individual two-dimensional (2-D) OCT images arranged in 3-D orientation. A fiber-based frequency domain OCT system that provides cross-sectional images was used to acquire 126 successive adjacent images for a sample volume of $6{\times}3.2{\times}2.5\;mm^3$. The axial resolution was $8\;{\mu}m$ in air. The 3-D OCT was able to demonstrate surface topography and subsurface disruption of articular cartilage consistent with the gross image as well as with histological cross-sections of the specimen. The 3-D OCT volumetric imaging of articular cartilage provides an enhanced appreciation and better understanding of regional degenerative joint disease than may be realized by individual 2-D OCT sectional images.

• The Journal of Society for e-Business Studies
• /
• v.25 no.4
• /
• pp.1-14
• /
• 2020

IT businesses in Korea have relatively strong regulations. While providing the same service, domestic businesses are in a situation of 'reverse discrimination of regulations' as they are less competitive than global IT companies in accordance with the application of the personal information protection legislation in Korea. In this paper, Personal Information Protection legislation was classified and laws of major countries were analyzed in comparative ways. It also compared and analyzed the "private policy" presented by representative Internet sites (Naver, Daum, Google, Facebook) that provide services to users in Korea. We also proposed three aspects of legislation improvement to address reverse discrimination.

• The Journal of the Korea Contents Association
• /
• v.17 no.9
• /
• pp.184-191
• /
• 2017

Smartphone has become a part of many people's daily lives. The mobile messenger function on the smartphone in particular is the most frequently used services. The mobile communication tool in the age of digital media can be classified into two big categories: text messages and emoticons, the non-verbal expression tool of one's emotions. This thesis has studied the mobile communications made by the non-verbal tool of emoticons. The history of emoticons traces back to the text-based emoticon created by Scott Fahlman, from which graphical emoticons were developed and the sound and animation effects have been added. Many people use emoticons and diverse companies are developing the tool. In this study, the representative emoticon development case of Line Co., Ltd. is analyzed to see the concept, types, development process, collaborations and merchandising of the emoticons. Based on the case of Line, the development orientation and direction of domestic emoticons will be discussed to be culture contents.

• Composites Research
• /
• v.37 no.1
• /
• pp.40-45
• /
• 2024

In this research, we introduce a novel approach that employs a 3D convolutional neural network (CNN) model to predict the permeability of Gas Diffusion Layers (GDLs). For training the model, we create an artificial dataset of GDL representative volume elements (RVEs) by extracting morphological characteristics from actual GDL images obtained through X-ray tomography. These morphological attributes involve statistical distributions of porosity, fiber orientation, and diameter. Subsequently, a permeability analysis using the Lattice Boltzmann Method (LBM) is conducted on a collection of 10,800 RVEs. The 3D CNN model, trained on this artificial dataset, well predicts the permeability of actual GDLs.