• International journal of advanced smart convergence
• /
• v.10 no.3
• /
• pp.89-96
• /
• 2021

In various areas of the 4th industry, a big issue is software quality enhancement for stability and reliability of the smart software systems. After revising software promotion law at 2020, we must clearly define requirements and separate design parts and implementation parts of an all public software development contracts. In this study, we need to validate whether the final implementation of software is followed by the original design or not. To do this, we consider the design restoration through software visualization based on reverse engineering. Therefore we propose an UML design extraction and visualization method based on reverse engineering. Based on this, we may validate whether it is implemented according to the original design, and how much visualizes and includes the code the internal complexity for improvement of software quality.

• Nuclear Engineering and Technology
• /
• v.53 no.1
• /
• pp.30-43
• /
• 2021

In the 2D/1D method, a global adjoint CMFD based on the generalized equivalence theory is built to synthesize the 2D radial MOC adjoint and 1D axial NEM adjoint calculation and also to accelerate the iteration convergence of 3D whole-core adjoint transport calculation. Even more important, an advanced yet accurate two-level (TL) CMFD acceleration technique is proposed, in which an equivalent one-group adjoint CMFD is established to accelerate the multi-group adjoint CMFD and then to accelerate the 3D whole-core adjoint transport calculation efficiently. Based on these method, a new code is developed to perform 3D adjoint neutron flux calculation. Then a set of VERA and C5G7 benchmark problems are chosen to verify the capability of the 3D adjoint calculations and the effectiveness of TL CMFD acceleration. The numerical results demonstrate that acceptable accuracy of 2D/1D adjoint calculations and superior acceleration of TL CMFD are achievable.

• Advances in materials Research
• /
• v.12 no.4
• /
• pp.273-286
• /
• 2023

The fracture mechanics make it possible to characterize the behavior with cracking of structures using parameters quantifiable in the sense of the engineer, in particular the stress field, the size of the crack, and the resistance to cracking of the material. Any structure contains defects, whether they were introduced during the production of the part (machining or molding defects for example). The aim of this work is to determine numerically by the finite element method the stress concentration factor Kt of a plate subjected to a tensile loading containing a lateral form defect with different sizes: a semicircle of different radii, a notch with different opening angles and a crack of different lengths. The crack propagation is then determined using the extended finite element technique (X-FEM). The modeling was carried out using the ABAQUS calculation code.

• Nuclear Engineering and Technology
• /
• v.56 no.2
• /
• pp.520-525
• /
• 2024

The optimization design problem of nuclear reactor radiation shield is a typical multi-objective optimization problem with almost 10 sub-objectives and the sub-objectives are always demanded to be under tolerable limits. In this paper, a design method combining multi-objective optimization algorithms with paralleling discrete ordinate transportation code is developed and applied to shield design of the Savannah nuclear reactor. Three approaches are studied for light-weighted and compact design of radiation shield. Comparing with directly optimization with 10 objectives and the single-objective optimization, the approach by setting sub-objectives representing weight and volume as optimization objectives while treating other sub-objectives as constraints has the best performance, which is more suitable to reactor shield design.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2000.04a
• /
• pp.17-17
• /
• 2000

A magnitude of 7.3 in Richter scale earthquake the strongest in-land earthquake in hundred years struck central Taiwan on September 21, 1999. It caused over 2,400 deaths and 30 some trillion won losses. To give an overview of this devastating earthquake this presentation will cover the following topics: 1) Introduction to Taiwan historical and 921 earthquake. 2) Damages to people landslide building dam bridge tank power facility etc. 3) Strong motion data and its characteristics. 4) Some changes to the building code triggered by the experience of the earthquake. Finally a concluding remark will be made.

• Journal of Plant Biology
• /
• v.28 no.3
• /
• pp.217-224
• /
• 1985

Because Ceramium fastigiatum Harvey (1834) is a later homonym of C. fastigiatum Roth (1806), a quite different plant from the former, it becomes illegitimate and must be rejected under the Article 64 of International Code of Botanical Nomenclature. For this reason, we suggest to give a new name, Ceramium fastigiramosum Boo et Lee, to the former species, keeping the original specific epithet‘fastigiatum’. The morphology of vegetative and reproductive structures is re-examined. The life history is confirmed as a Polysiphonia-type in laboratory culture.

• Publications of The Korean Astronomical Society
• /
• v.2 no.1
• /
• pp.13-20
• /
• 1985

Magnetic reconnect ion is studied numerically by means of a two dimensional MHD code. The initial magnetic field configuration is the two-dimensional dipole field, and the simulation model involves magnetic reconnect ion driven by the magnetized plasma flow. Strong plasma jetting, plasmoid formation and its fast ejection are observed in the downstream region. The dependence of reconnection rate on the incoming energy flux is found to be very sensitive, while the magnitude of the resistivity does not influence much on the reconnection rate. The simulation results are discussed in the context of the geomagnetic substorm.

• Geomechanics and Engineering
• /
• v.22 no.2
• /
• pp.133-142
• /
• 2020

The evolution of the mining-induced fracture network formed during longwall top coal caving (LTCC) has a great influence on the gas drainage, roof control, top coal recovery ratio and engineering safety of aquifers. To reveal the evolution of the mining-induced stress and fracture network formed during LTCC, the fracture network in front of the working face was observed by borehole video experiments. A discrete element model was established by the universal discrete element code (UDEC) to explore the local stress distribution. The regression relationship between the fractal dimension of the fracture network and mining stress was established. The results revealed the following: (1) The mining disturbance had the most severe impact on the borehole depth range between approximately 10 m and 25 m. (2) The distribution of fractures was related to the lithology and its integrity. The coal seam was mainly microfractures, which formed a complex fracture network. The hard rock stratum was mainly included longitudinal cracks and separated fissures. (3) Through a numerical simulation, the stress distribution in front of the mining face and the development of the fracturing of the overlying rock were obtained. There was a quadratic relationship between the fractal dimension of the fractures and the mining stress. The results obtained herein will provide a reference for engineering projects under similar geological conditions.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.10
• /
• pp.1092-1097
• /
• 2009

A novel exopolysaccharide named Ebosin was produced by Streptomyces sp. 139, with medicinal activity. Its biosynthesis gene cluster (ste) has been previously identified. For the functional study of the ste7 gene in Ebosin biosynthesis, it was disrupted with a double crossover via homologous recombination. The monosaccharide composition of EPS-7m produced by the mutant strain Streptomyces sp. 139 ($ste7^-$) was found altered from that of Ebosin, with fucose decreasing remarkably. For biochemical characterization of Ste7, the ste7 gene was cloned and expressed in Escherichia coli BL21. With a continuous coupled spectrophotometric assay, Ste7 was demonstrated to have the ability of catalyzing the transfer of fucose specifically from GDP-$\beta$-L-fucose to a fucose acceptor, the lipid carrier located in the cytoplasmic membrane of Streptomyces sp. 139 ($ste7^-$). Therefore, the ste7 gene has been identified to code for a fucosyltransferase, which plays an essential role in the formation of repeating sugars units during Ebosin biosynthesis.

• Geomechanics and Engineering
• /
• v.23 no.5
• /
• pp.467-480
• /
• 2020

The failure behavior and tensile strength of sandstone materials under different strain rates are greatly different, especially under static loads and impact loads. In order to clearly investigate the failure mechanism of sandstone materials under static and impact loads, a series of Brazilian disc samples were used by employing green sandstone, red sandstone and black sandstone to carry out static and impact loading splitting tensile tests, and the failure properties subjected to two different loading conditions were analyzed and discussed. Subsequently, the failure behavior of sandstone materials also were simulated by finite element code. The good agreement between simulation results and experimental results can obtain the following significantly conclusions: (1) The relationship of the tensile strength among sandstone materials is that green sandstone < red sandstone < black sandstone, and the variation of the tensile sensitivity of sandstone materials is that green sandstone > red sandstone > black sandstone; (2) The mainly cause for the difference of dynamic tensile strength of sandstone materials is that the strength of crystal particles in sandstone material, and the tensile strength of sandstone is proportional to the fractal dimension; (3) The dynamic failure behavior of sandstone is greatly different from that of static failure behavior, and the dynamic tensile failure rate in dynamic failure behavior is about 54.92%.