• The Bulletin of The Korean Astronomical Society
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• v.36 no.1
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• pp.87.1-87.1
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• 2011

We analyze the I-GALFA HI 21-cm line survey data in order to study the characteristics of interstellar turbulence in the neutral hydrogen medium in the Galaxy. We select several regions of 4.3 deg x 4.3 deg area near or far from the galactic plane both in the inner and outer Galaxy, transform the power of those regions into Fourier planes and derive one- and two-dimensional power spectra of HI emission. Our Fourier-analysis shows that the iso-power contours generally elongate along the latitude direction more in the outermost spiral arm, which indicates that the HI structure is "filamentary" and mainly aligned along the longitude. At high latitudes or in the interarm region, on the other hand, the iso-power contours are close to circles implying that the HI structures are randomly distributed or "clumpy". In the inner Galaxy, we derive two-dimensional spectra both far from and near the arm and explore the nature of the turbulence.

• The Transactions of the Korea Information Processing Society
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• v.6 no.7
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• pp.1738-1748
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• 1999

Recent simulation tools combine the 3-dimensional graphic technique to implement the 3D visualization of the objects in the 2-Dimensional computer display. In this paper, a sight simulation tool is implemented using the recent 3D techniques. The proposed sight simulator can be applied to improve the human environment with the harmony of the nature. The system is consisted of modules for topography, object, and navigation. A sight database for the sight elements(objects) is implemented using Java. Combined with Java, VRML, which is considered as the standard for 3D virtual reality in the Internet is used to implement EAI(External Authoring Interface). EAI allows the users to communicate with a VRML scene.

• Advances in materials Research
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• v.9 no.1
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• pp.1-14
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• 2020

The hybrid method of three-dimensional ion implantation and electric arc is presented as a novel plasma-ion technique that allows by means of high voltage pulsed and electric arc discharges, the bombardment of non-metallic and metallic ions then implanting upon the surface of a solid surface, especially out of metallic nature. In this study AISI/SAE 4140 samples, a tool type steel broadly used in the industry due to its acceptable physicochemical properties, were metallographically prepared then surface modified by implanting titanium and simultaneously titanium and nitrogen particles during 5 min and 10 min. The effect of the ion implantation technique over the substrate surface was analysed by characterization and electrochemical techniques. From the results, the formation of Ti micro-droplets upon the surface after the implantation treatment were observed by micrographs obtained by scanning electron microscopy. The presence of doping particles on the implanted substrates were detected by elemental analysis. The linear polarization resistance, potentiodynamic polarization and total porosity analysis demonstrated that the samples whose implantation treatment with Ti ions for 10 min, offer a better protection against the corrosion compared with non-implanted substrates and implanted at the different conditions in this study.

• Fashion & Textile Research Journal
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• v.21 no.5
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• pp.527-539
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• 2019

This study examined the Chinese style in the Vivienne Tam collection as well as explored diversity and modern interpretation of a Chinese style used in modern fashion. The study also investigated the concept and history of the Chinese style as well as analyzed the Chinese style in the collection based on a consideration of a Chinese element that is the basic structure with an understanding of Vivienne Tam and general collection themes. As a result of research, the Chinese style appeared in the Vivienne Tam collection was comprehensive with 43 Chinese elements including Animals, Flower & Grass among the Nature elements, Mythology Religion among the Figure elements, Historical Artifacts, Clothing, Oral Literature, Entertainment, Fine Arts. Technique, Folk holiday among Culture elements and Philosophy among Spirit elements, which accounted for 57.6% of the collection. The formative characteristics that included Chinese elements were extended, abstracted, distorted or transformed; in addition, some abstract elements were embodied into animals, images and certain particular forms to present a theme. In addition to two-dimensional method to print Chinese elements on fabric, they were also expressed as a three-dimensional texture or a silhouette, achieving clear and bold harmony. The aesthetic characteristic is a mixture of Eastern and Western way of thinking. Her costume has a political and historical meaning beyond the imitation of elements that represent the development of a pleasant and interesting design.

• Progress in Medical Physics
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• v.32 no.2
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• pp.25-39
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• 2021

Brachytherapy, along with external beam radiation therapy (EBRT), is an essential and effective radiation treatment process. In brachytherapy, in contrast to EBRT, the radiation source is radioisotopes. Because these isotopes can be positioned inside or near the tumor, it is possible to protect other organs around the tumor while delivering an extremely high-dose of treatment to the tumor. Brachytherapy has a long history of more than 100 years. In the early 1900s, the radioisotopes used for brachytherapy were only radium or radon isotopes extracted from nature. Over time, however, various radioisotopes have been artificially produced. As radioisotopes have high radioactivity and miniature size, the application of brachytherapy has expanded to high-dose-rate brachytherapy. Recently, advanced treatment techniques used in EBRT, such as image guidance and intensity modulation techniques, have been applied to brachytherapy. Three-dimensional images, such as ultrasound, computed tomography, magnetic resonance imaging, and positron emission tomography are used for accurate delineation of treatment targets and normal organs. Intensity-modulated brachytherapy is anticipated to be performed in the near future, and it is anticipated that the treatment outcomes of applicable cancers will be greatly improved by this treatment's excellent dose delivery characteristics.

• Nuclear Engineering and Technology
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• v.55 no.5
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• pp.1911-1923
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• 2023

The nuclear safety assessment involving large transient simulations is forcing the community to develop methods for coupling thermal-hydraulics and neutronic codes and three-dimensional (3D) Computational Fluid Dynamics (CFD) codes. In this paper a set of dynamic boundary conditions are implemented in OpenFOAM^Ⓡ in order to apply zero-dimensional (0D) approaches coupling with 3D thermal-hydraulic simulation in a single framework. This boundary conditions are applied to model pipelines, tanks, pumps, and heat exchangers. On a first stage, four tests are perform in order to assess the implementations. The results are compared with experimental data, full 3D CFD, and system code simulations, finding a general good agreement. The semi-implicit implementation nature of these boundary conditions has shown robustness and accuracy for large time steps. Finally, an application case, consisting of a simplified open pool with a cooling external circuit is solved to remark the capability of the tool to simulate thermal hydraulic systems commonly found in nuclear installations.

• Journal of architectural history
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• v.32 no.5
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• pp.7-20
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• 2023

This study aims to reveal the multilayered nature of the formal aspects of communal house architecture in North Korea. It is said that Kim Jong Il, who emerged as a successor after the mid-1970s, brought about a change in the architecture, leading the construction of a sculptural communal house on Gwangbok Street in 1989, and wrote The art of architecture (1992), which theorized architecture as an object of art. Therefore, it is widely perceived that the communal house was transformed from a simple form of living function to an artistic architecture with the rise of Kim Jong Il. This study, however, argues that this change was the result of an internal evolution in North Korean architecture, rather than a simple change in the position of an individual in power. It seeks to move away from the dichotomy that divides the communal house into two periods: the "KimIl-sung period," in which the communal house was laid out in a simple form to provide mass supply and a socialist lifestyle, and the "Kim Jong-il period," in which the communal house took on an artistic form, such as the Gwangbok Street communal house, in the early years of reconstruction. In the 1950s and 1960s, before KimJong-il's arrival, the communal house form was not simply a flat arrangement, but a three-dimensional and sculptural consideration of the effect on the cityscape.

• Journal of Information Technology and Architecture
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• v.10 no.1
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• pp.79-91
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• 2013

This paper proposes a systematic methodology that could be used to decide which one shows the best performance among space filling curves (SFCs) in applying lower-dimensional transformations to histogram sequences. A histogram sequence represents a time-series converted from an image by the given SFC. Due to the high-dimensionality nature, histogram sequences are very difficult to be stored and searched in their original form. To solve this problem, we generally use lower-dimensional transformations, which produce lower bounds among high dimensional sequences, but the tightness of those lower-bounds is highly affected by the types of SFC. In this paper, we attack a challenging problem of evaluating which SFC shows the better performance when we apply the lower-dimensional transformation to histogram sequences. For this, we first present a concept of spatial locality, which comes from an intuition of "if the entries are adjacent in a histogram sequence, their corresponding cells should also be adjacent in its original image." We also propose spatial locality preservation metric (slpm in short) that quantitatively evaluates spatial locality and present its formal computation method. We then evaluate five SFCs from the perspective of slpm and verify that this evaluation result concurs with the performance evaluation of lower-dimensional transformations in real image matching. Finally, we perform k-NN (k-nearest neighbors) search based on lower-dimensional transformations and validate accuracy of the proposed slpm by providing that the Hilbert-order with the highest slpm also shows the best performance in k-NN search.

• Journal of Wetlands Research
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• v.15 no.1
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• pp.91-103
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• 2013

In this Research, in order to improve problems of not enough technical validation and structural and hydraulic stability evaluation when nature-friendly revetment block is applied to field, hydraulic stability evaluation according to hydraulic behavior change of porosity soil block for vegetation reinforcement that secures ecological function was reviewed. By selecting object section, numerical analysis and hydraulic model experiments were performed; for numerical analysis, by using 1-dimensional numerical analysis model HEC-RAS and 2-dimensional numerical analysis RMA-2, one-dimensional(1D) and two-dimensional(2D) numerical analysis were performed; by applying Froude's similarity law, reduced-scale hydraulic model experiments according to vegetation existence were performed. In hydraulic model experiment, for validity of experiment result, the result of velocity and tractive force of reduced-scale hydraulic model experiments was converted to prototype so that it can be compared and reviewed under the same condition of one-dimensional(1D) and two-dimensional(2D) numerical analysis result; as a result, it was confirmed that comparatively united result appeared, and by comparing prototype-converted tractive force result with revetment's allowable tractive force coming from an existing research, block's hydraulic stability was suggested.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.4 no.1
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• pp.45-58
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• 1992

A three-dimensional hydrodynamic numerical model is used to compute the annual and seasonal meteorologically-induced residual circulation on the Yellow Sea and the East China Sea continental shelf. The model is formulated having irregular coastal boundaires and non-uniform depth distribution representative of nature. The previous three-dimensional model of the East China Sea (Choi. 19U) has been further refined to resolve the flow over the continental shelf in more detail. The mesh resolution of the present finite difference grid system used is 4 minutes latitude by 5 minutes longitude over the entire shelf. The circulation pattern showing depth and spatial distribution of currents over the Yellow Sea and the East China Sea is presented. Meteorologically-induced currents are subsequently used to compute turn-over times for the three depths (surface. mid-depth. bottom) and the total water column of various regions of the Yellow Sea and the East China Sea.