• Advances in aircraft and spacecraft science
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• v.9 no.4
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• pp.279-300
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• 2022

This paper analyzes the possibilities of a new method to using TLE data for detecting satellite maneuvers. The method has a number of advantages over other methods that are designed to detect maneuvers. It allows not only to detect maneuvers, but also to get a more complete picture of the maneuver. In particular, the method makes it possible to estimate the moments of the beginning and end of the maneuver, calculate the changes in the orbital elements, evaluate the tangential and binormal components of the impulse, and finally, calculate the impulse of the satellite obtained as a result of the maneuver. To demonstrate in detail the capabilities of the algorithm, the proposed method was applied to one of LEO satellites - TIANHUI-1 satellite. After the efficiency of the method was proved, this method was applied to the China Space Station - TIANHE-1 (CSS), Starlink-1095 and Starlink-2305 satellites. The maneuvers of the CSS and Starlink-1095 satellite during their close encounter on 1 July, 2021, and the CSS and Starlink-2305 satellite during their close encounter on 21 October, 2021 are analyzed in detail. The minimum distances between the CSS and Starlink satellites at the moments of their maximum approaches are estimated. An estimate of the computation time of this algorithm is given, and the possibility of its use for monitoring maneuvers or other anomalous orbital changes of a large number of satellites in near real-time is shown. It is assumed that on the basis of this method, a service for monitoring satellite maneuvers can be created.

• Steel and Composite Structures
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• v.44 no.5
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• pp.633-649
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• 2022

This paper is first implemented with the bending behavior of three-dimensional functionally graded (3DFG) plates in the framework of level set-based topology optimization (LS-based TO). Besides, due to the suitable properties of the current design domain, the thin-plate spline (TPS) is recognized as a RBF to construct the LS function. The overall mechanical properties of the 3DFG plate are assessed using a power-law distribution scheme via Mori-Tanaka micromechanical material model. The bending response is obtained using the first-order shear deformation theory (FSDT). The mixed interpolation of four elements of tensorial components (MITC4) is also implemented to overcome a well-known shear locking problem when the thickness becomes thinner. The Hamilton-Jacobi method is utilized in each iteration to enforce the necessary boundary conditions. The mathematical formulas are expressed in great detail for the LS-based TO using 3DFG materials. Several numerical examples are exhibited to verify the efficiency and reliability of the current methodology with the previously reported literature. Finally, the influences of FG materials in the optimized design are explained in detail to illustrate the behaviors of optimized structures.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.6
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• pp.557-567
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• 2015

With the increasing demands of 3D spatial information in urban environment, the importance of point clouds generation techniques have been increased. In particular, for as-built BIM, the point clouds with the high accuracy and density is required to describe the detail information of building components. Since the terrestrial LiDAR has high performance in terms of accuracy and point density, it has been widely used for as-built 3D modelling. However, the high cost of devices is obstacle for general uses, and the image-based 3D reconstruction technique is being a new attraction as an alternative solution. This paper compares the image-based 3D reconstruction technique and the terrestrial LiDAR in point of establishing the as-built BIM of outdoor structures. The point clouds generated from the image-based 3D reconstruction technique could roughly present the 3D shape of a building, but could not precisely express detail information, such as windows, doors and a roof of building. There were 13.2~28.9 cm of RMSE between the terrestrial LiDAR scanning data and the point clouds, which generated from smartphone and DSLR camera images. In conclusion, the results demonstrate that the image-based 3D reconstruction can be used in drawing building footprint and wireframe, and the terrestrial LiDAR is suitable for detail 3D outdoor modeling.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.11
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• pp.1074-1081
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• 2011

As robotics systems are becoming more complex there is the need to promote component based robot development, where systems can be constructed as the composition and integration of reusable building block. One of the most important challenges facing component based robot development is safeguarding against software component failures and malfunctions. The health monitoring of the robot software is most fundamental factors not only to manage system at runtime but also to analysis information of software component in design phase of the robot application. And also as a lot of monitoring events are occurred during the execution of the robot software components, a simple data treatment and efficient memory management method is required. In this paper, we propose an efficient events monitoring and data management method by modeling robot software component and monitoring factors based on robot software framework. The monitoring factors, such as component execution runtime exception, Input/Output data, execution time, checkpoint-rollback are deduced and the detail monitoring events are defined. Furthermore, we define event record and monitor record pool suitable for robot software components and propose a efficient data management method. To verify the effectiveness and usefulness of the proposed approach, a monitoring module and user interface has been implemented using OPRoS robot software framework. The proposed monitoring module can be used as monitoring tool to analysis the software components in robot design phase and plugged into self-healing system to monitor the system health status at runtime in robot systems.

• Journal of Ginseng Research
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• v.32 no.1
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• pp.62-66
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• 2008

Non-saponin gingseng fraction components (NSRG) have been known to have a variety of biological activity. However, the effects of these components on the function of brain cell have not been characterized in detail. In this study, we investigated the preventive effect of non-saponin red ginseng components on acrylamide (ACR)-induced suppression of neural cell adhesion molecule (NCAM), which is highly expressed in neuronal cells. The data showed that NSRG blocked the suppression of NCAM expression by ACR in neuroblastoma cells (SK-N-SH). In addition, NSRG significantly increased NCAM expression in ACR-nontreated neuroblastoma cells. NSRG treatment resulted in the increase of cell proliferation in a concentration-dependent manner. We also examined whether NSRG could modulate the NO production of astrocytes. When glioma cells (C6) were treated with various concentrations of NSRG (100-300 ug/ml) in the presence or absence of $IFN-{\gamma}$ for 24 hours, NO production was suppressed in $IFN-{\gamma}-$stimulated C6 cells. Taken together, these results demonstrate that treatment of brain cells with NSRG results in the enhancement of proliferation, the suppression of NO production and the protective effect on NCAM expression impaired by ACR. Thus, the present data suggest that NSRG has proliferative and neuroprotective effects and these effects could be useful in neuronal diseases.

• Journal of Engineering Education Research
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• v.15 no.3
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• pp.47-58
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• 2012

The purpose of this paper is to verify the education effects of program for engineering students and extract the essential components to be included in the learning contents. For this, we investigated the lecture contents critically and analyzed the evaluation result of questionnaire to examine the students' learning satisfaction and learners' needs concerning the effectiveness of course. The survey using two types of questionnaires was conducted with 210 junior and senior students taking lectures of ${\ll}$Presentation and Debate Skills${\gg}$ in the college of engineering at Pusan National University. According to the evaluation result, students experienced various speech education's effects concerning (1) verbal components, (2) non-verbal components, (3) problem solving competence, (4) teamwork skills, etc. On the other side there have been pointed out as problems in the ${\ll}$Presentation and Debate Skills${\gg}$ class, such as (1) a large number of assignments, (2) insufficiency of more refined evaluation method for the individuals and (3) a well-balanced arrangement between 'theory' and 'practice' was needed. However more importantly, the individual students can not do practice sufficiently owing to the large scale of class. Therefore the various and effective ways to help students improve their communicative competence have to be developed further. Finally, there have been extracted several essential components to be included in the class and implications for ameliorating the class were discussed and suggested in detail.

• Journal of Korea Technology Innovation Society
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• v.10 no.4
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• pp.789-807
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• 2007

Technology Readiness Levels were initially proposed by NASA in 1995. TRL's definition and range were modified within adopted feilds such as hardware and software products. Many national R&D programs have similar evaluation conditions. However, they are influenced by the experts' ability. Relatively, they have shown the little reliance and the low performance of the developed prototype and technology. The purpose of this study is to apply the TRL to the materials and components development program. We defined TRLs for the program and devided them in three technology fields. Proposals, which were submitted for the program in 2007, were assessed with our TRL definitions for the study on the applicability. As a result, we could understand the characteristic TRLs of the technical proposals to the materials and components development program. This shows that the objective tools such as TRLs are required as the R&D program management factors. For the sake, it is the important factor that the detail directives to assess TRL should be developed according to the branches of industrial technology fields.

• Journal of Digital Convergence
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• v.11 no.12
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• pp.333-338
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• 2013

This paper was aimed to represent 3D design process to enable the construction design in a smart phone. The construction design was done in pattern units, by composing construction materials in components first, followed by assembling the components in pattern. Four types of views were constructed and each function was described to enable construction design in mobile environment. In addition, the skills needed for each view were described in detail through the libraries used. The process and calculation results were shown in mobiles how each view performed its function and behave worked together with a complementary way based on this implementation technique.

• Journal of KIISE:Software and Applications
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• v.30 no.5_6
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• pp.515-528
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• 2003

Component Based Software Development has been recognized as a new software development paradigm, and received much attention among researchers. However, it requires software architecture based development to assure component reusability and efficient software development. This paper proposes the Component Based 4+1 View Model of software architecture to support component based software development. It is redefined on the basis of the existing 4+1 view model of software architecture developed by Kruchten. Also, we describe the elements of the view model in detail with UML. This architecture constructs the foundation of component based software such as increasing the understanding of software and providing the information about how the components interact with each other. It can be done by exposing the context for the use of software components to each views.

• Journal of the Korean Society of Costume
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• v.63 no.3
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• pp.17-32
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• 2013

This study examined the visual elements of the Trompe l'oeil design and the combination conditions of each element in order to deduce the form generation diagrams of Trompe l'oeil fashion design. The following is what the study found: First, Trompe l'oeil fashion design can be divided into two based on its subject: 'the combination of internal elements of dress' and 'the combination of external elements of dress'. Looking at the visual components of each type, depending on the subject, 'the combination of internal elements of dress' design was achieved by combining internal dress elements: including textile, detail, item, accessory, layering, etc.. In case of 'the combination of external elements of dress' design, the object of Trompe l'oeil was expanded in scope to environment, which includes the actions of a wearer. Second, as for Trompe l'oeil fashion design through the combination of external dress elements, the condition to combined visual components of the work in the process of creation was related to 'the popularity of object', 'the similarity of shapes and sizes', and 'the probability of location'. Third, deriving a form generation diagrams of Trompe l'oeil fashion design was very effective in delineating specific relationships and conditions, directions among elements combined in fashion design.