• Journal of the Korean housing association
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• v.22 no.1
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• pp.35-42
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• 2011

The objective of this study is to investigate the functional conformity based on the analysis of the spatial connectivity of block housing using space syntax. Three cases were selected which have important meanings in 1920s. The properties of spatial configuration were derived from an urban-context approach and without urban context analysis, and spatial connectivity and functional conformity were analyzed using references. The results of the study revealed that the arrangement of block housing were different from one another notwithstanding their similar layout characteristics. The relationships between urban streets and housing complexes were identified, and the public spaces were being arranged as semi-public spaces, whereas blocks as private spaces by separating functions. This study provides the implications for the planning of low rise-high density housings by means of analyzing the spatial connectivity of the spatial layout characteristics of European block housing, recognizing the relationships between urban communities and housing complexes.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.5
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• pp.375-380
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• 2012

In this study, dynamic load and dynamic contact force between a building block and wire ropes of a goliath crane are calculated during lifting or turn-over of a building block for the design of an optimal lug arrangement system. In addition, a multibody dynamics kernel for implementing the system were developed. In the multibody dynamics kernel, the equations of motion are constructed using recursive formulation. To evaluate the applicability of the developed kernels, the interferences and dynamic contact force between the building block and wire ropes were calculated and then the hull structural analysis for the block was performed using the calculation result.

• Journal of Information Technology Services
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• v.17 no.4
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• pp.163-189
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• 2018

In this study, we analyze the acceptance theories of insurance services using blockchain technology. Although insurance services using block-chain technology are still in discussion, specific development methods for service methods applying block-chain technology in insurance services are being studied. In this study, the following analysis was conducted to analyze the acceptance of insurance services using block chain technology, focusing on four factors of the UTAUT model. As a result of the analysis, the technology benefits of the blockchain affecting the performance expectations of UTAUT are security and reliability. In addition, the factors influencing UTAUT's effort expectations were found to be availability and economics. Therefore, it was found that performance expectation and effort expectation for technology acceptance are influenced by different technology benefits. Among the four factors of UTAUT, the factors affecting the insurance service using the blockchain technology are performance expectation and effort expectation, and social influence and promotion condition have no effect on acceptance intention. Also, the moderating effect of user innovation on acceptance intention of insurance service applying blockchain was significant only for effort expectation among UTAUT factors.

• Geomechanics and Engineering
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• v.17 no.3
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• pp.279-285
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• 2019

The process of slope stability analysis is one of the most important stages in design of some civil and mining projects. Bimslopes are made from bimrocks (block-in-matrix rocks) where rocky blocks are distributed in a bonded matrix of finer texture. These kind of slopes are often seen in weathered and near-surface depths. Previous studies have shown that VBP (Volumetric Block Proportion) is one of the most significant factors affecting bimrocks strength and consequently the stability of bimslopes. In this paper, the influence of block inclinations on bimslope stability have been investigated. For this purpose, 180 theoretical models have been made with various VBPs, all of them have a specified block size distribution. These bimslopes contain blocks with differing dips relative the slope inclination. Also for each kind of block inclination, 10 different blocks arrangements have been modeled. The Finite Element Method (FEM) was used to analysis the stability of these bimslopes models. The results showed the inclination of blocks has a strong impact on the Safety Factor and stability of bimslopes. When the difference in angle of dip of blocks relative to the slope angle is maximum, the Safety Factor of bimslopes tends to be a maximum compared with the matrix-only state. Furthermore, with increasing VBP of bimslopes stability increases. The graphs obtained from this study could be used for preliminary guidance in the projects design with bimslopes.

• Journal of The Korean Society of Agricultural Engineers
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• v.65 no.2
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• pp.47-57
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• 2023

The increase of impermeable area ratio is causing hydrologic cycle problems in urban areas and groundwater depletion in rural areas, permeable pavements are getting attention to expand permeable areas. The performance of the permeable concrete block pavement, which is part of the permeable pavement, is greatly affected by the porosity. In addition, the permeability coefficient is a major factor when designing permeable concrete block pavement. Existing porosity and permeability test methods have problems such as uneconomical or poor field applicability. The object of this study was to develop a methodology for evaluating porosity and permeability coefficient using a surface image of a permeable concrete block. Specimens are manufactured with various porosity ranges and porosity and permeability tests are performed. After surface image preprocessing, normalization and binarization methods were compared. Through this, the method with the highest correlation with the lab test result was determined. From the results, the PDR (pore determined ratio) was obtained. Simple linear regression analysis is performed with PDR and lab test results. The results showed a high correlation of R² more than 0.8, and the errors were also low.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.7
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• pp.3608-3628
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• 2017

Several block cipher modes of operation have been proposed in the literature to protect sensitive information. However, different security analysis models have been presented for attacking them. The analysis indicated that most of the current modes of operation are vulnerable to several attacks such as known plaintext and chosen plaintext/cipher-text attacks. Therefore, this paper proposes a secure block cipher mode of operation to thwart such attacks. In general, the proposed mode combines one-time chain keys with each plaintext before its encryption. The challenge of the proposed mode is the generation of the chain keys. The proposed mode employs the logistic map together with a nonce to dynamically generate a unique set of chain keys for every plaintext. Utilizing the logistic map assures the dynamic behavior while employing the nonce guarantees the uniqueness of the chain keys even if the same message is encrypted again. In this way, the proposed mode called SPCBC can resist the most powerful attacks including the known plaintext and chosen plaintext/cipher-text attacks. In addition, the SPCBC mode improves encryption time performance through supporting parallelized implementation. Finally, the security analysis and experimental results demonstrate that the proposed mode is robust compared to the current modes of operation.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.6 no.1
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• pp.53-61
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• 2011

Objective: The purpose of this study is to evaluate the disc block subluxation for lumbar scoliosis and herniation of nucleus pulpous (HNP). Methods: We used AP & Lateral view X-ray for patients. And we measured of disc wedge angle, vertebral body rotation to evaluate the typical and atypical disc block subluxation. Results: On the analysis of the lateral view X-ray, 4th lumbar intervertebral disc angle (I.V.D angle) showed $4^{\circ}$, $5^{\circ}$, $3^{\circ}$, $0^{\circ}$ in the cases. On the 4th lumbar analysis of the AP view X-ray, lumbar scoliosis showed right disc wedge angle was $11^{\circ}$ (case 1), $17^{\circ}$ (case 2) and left vertebral body rotation was 13mm, 6mm. Lumbar HNP showed left disc wedge angle was $5^{\circ}$ (case 3), $4^{\circ}$ (case 4) and left vertebral body rotation was 2mm, 4mm. Conclusions: Disc block subluxation has been in lumbar scoliosis, but not been in lumbar HNP.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.6
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• pp.660-669
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• 2016

A fluorinated-sulfonated, hydrophobic-hydrophilic copolymer was planed subsequently synthesized using typical nucleophilic substitution polycondensation reaction. A novel AB and ABA (or BAB) block copolymers were synthesized using sBCPSBP (sulfonated 4,4'-bis[4-chlorophenyl)sulfonyl]-1,1'-biphenyl), DHN (1,5-dihydroxynaphthalene), DFBP (decafluorobiphenyl) and HFIP (4,4'-hexafluoroisopropylidenediphenol). All block copolymers were easily cast and made into clear films. The structure and synthesized copolymers and corresponding membranes were analyzed using GPC (gel permeation chromatography), $^1H$-NMR ($^1H$ nuclear magnetic resonance) and FT-IR (Fourier transform infrared). TGA (Thermogravimetric analysis) and DSC (differential scanning calorimetry) analysis showed that the prepared membranes were thermally stable, so that elevated temperature fuel cell operation would be possible. Hydrophobic/hydrophilic phase separation and clear ionic aggregate block morpology was confirmed in both triblock and diblock copolymer in AFM (atomic force microscopy), which may be highly related to their proton transport ability. A sulfonated BAB triblock copolymer membrane with an ion-exchange capacity (IEC) of 0.6 meq/g has a maximum ion conductivity of 40.3 mS/cm at $90^{\circ}C$ and 100% relative humidity.

• Structural Engineering and Mechanics
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• v.19 no.3
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• pp.347-359
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• 2005

This paper attempts to develop the analytical model of estimating the fatigue damage using a linear elastic fracture mechanics method. The stress history on a welding member, when a truck passed over a bridge, was defined as a block loading and the crack closure theory was used. These theories explain the influence of a load on a structure. This study undertook an analysis of the stress range frequency considering both dead load stress and crack opening stress. A probability method applied to stress range frequency distribution and the probability distribution parameters of it was obtained by Maximum likelihood Method and Determinant. Monte Carlo Simulation which generates a probability variants (stress range) output failure block loadings. The probability distribution of failure block loadings was acquired by Maximum likelihood Method and Determinant. This can calculate the fatigue reliability preventing the fatigue failure of a welding member. The failure block loading divided by the average daily truck traffic is a predictive remaining life by a day. Fatigue reliability analysis was carried out for the welding member of the bottom flange of a cross beam and the vertical stiffener of a steel box bridge by the proposed model. Results showed that the primary factor effecting failure time was crack opening stress. It was important to decide the crack opening stress for using the proposed model. Also according to the 50% reliability and 90%, 99.9% failure times were indicated.

• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1365-1381
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• 2023

In this paper, a procedure for evaluating the structural integrity of the PCSG (Printed Circuit Steam Generator) unit block is presented with a simplified FE (finite element) analysis technique by applying the homogenization method. The homogenization method converts an inhomogeneous elastic body into a homogeneous elastic body with same mechanical behaviour. This method is effective when the inhomogeneous elastic body has repetitive microstructures, and thus the method was applied to the sheet assembly among the PCSG unit block components. From the method, the homogenized equivalent elastic constants of the sheet assembly were derived. The validity of the determined material properties was verified by comparing the mechanical behaviour with the reference model. Thermo-mechanical analysis was then performed to evaluate the structural integrity of the PCSG unit block, and it was found that the contact region between the steam header and the sheet assembly is a critical point where large bending stress occurs due to the temperature difference.