• 한국군사과학기술학회지
• /
• 제9권1호
• /
• pp.5-12
• /
• 2006

This study describes an SDINS/GPS/ZUPT integration algorithm for land navigation systems. The SDINS error can be decoupled in two parts. The first part is the the Schuler component which does not depend on object motion parameters, and the other is the Non-Schuler part which depends on the product of object acceleration and azimuth error. Azimuth error causes SDINS error in proportion to the traversed distance. The proposed system consists of a GPS/SDINS integration system and an SDINS/ZUPT integration system, which are both realized by an indirect feedforward Kalman filter. The main difference between the two is whether the estimate includes the Non-Schuler error or not, which is decided by the measurement type. Consequently, subtracting GPS/SDINS outputs from SDINS/ZUPT outputs provide the Non-Schuler error information which can be applied to improving azimuth accuracy. Simulation results using the raw data obtained from a van test attest that the proposed SDINS/GPS/ZUPT system is capable of providing azimuth improvement.

• 한국CDE학회논문집
• /
• 제13권4호
• /
• pp.314-322
• /
• 2008

This paper introduces an integration of Product Data Management (PDM) and Software Configuration Management (SCM). PDM and SCM have supported development of mechanical products and software products respectively. The importance of software components in the current products increases rapidly since the software enables the products to satisfy various customer requirements efficiently. Therefore the current product development needs enhanced product data management that can control both the hardware and software data seamlessly. This paper proposes an extended product data model for integrating SCM into PDM. The extension enables PDM document management to support the version control for software development. It also enables engineers to control both the software and hardware parts as integrated data objects during product configuration and engineering change management. The proposed model is implemented by using a commercial Product Lifecycle Management (PLM) system and a development of a network based robot system is tested by the implemented product development environment.

• Earthquakes and Structures
• /
• 제8권6호
• /
• pp.1325-1348
• /
• 2015

Real-time hybrid testing (RTHT) involves virtual splitting of the structure into two parts: physical substructure that contains the key region of interest which is tested in a laboratory and numerical substructure that contains the remaining part of the structure in the form of a numerical model. This paper numerically assesses four step-by-step integration methods (Central difference method (CDM), Operator splitting method (OSM), Rosenbrock based method (RBM) and CR-integration method (CR)) which are widely used in RTHT. The methods have been assessed in terms of stability and accuracy for various realistic damping ratios of the physical substructure. The stability is assessed in terms of the spectral radii of the amplification matrix while the accuracy in terms of numerical damping and period distortion. In order to evaluate the performance of the methods, five carefully chosen examples have been studied - undamped SDOF, damped SDOF, instantaneous softening, instantaneous hardening and hysteretic system. The performance of the methods is measured in terms of a non-dimensional error index for displacement and velocity. Based on the error indices, it is observed that OSM and RBM are robust and performs fairly well in all the cases. CDM performed well for undamped SDOF system. CR method can be used for the system showing softening behaviour. The error indices indicate that accuracy of OSM is more than other method in case of hysteretic system. The accuracy of the results obtained through time integration methods for different damping ratios of the physical substructure is addressed in the present study. In the presence of a number of integration methods, it is preferable to have criteria for the selection of the time integration scheme. As such criteria are not available presently, this paper attempts to fill this gap by numerically assessing the four commonly used step-by-step methods.

• 소성∙가공
• /
• 제10권6호
• /
• pp.500-508
• /
• 2001

The integration of Rapid prototyping (RP) and Rapid Tooling (RT) has the potential for rapid net shaping of thee-dimensional parts, which have a geometrical complexity. In this study, a new R)P process, (VLM-SP), was proposed to manufacture net shapes of three-dimensional prototypes and it was shown that VLM-SP is an effective and economic process through the comparison of building time, building cost and dimensional accuracy for the test parts with the commercial RP processes ; LOM and FDM. In addition, the metal parts, which are a spanner shape and a clover punch, were produced by the plaster casting as one of RT using the prototypes of VLM-SP.

• 아동학회지
• /
• 제35권1호
• /
• pp.17-41
• /
• 2014

This study explored the sandplay therapy case of a 5th grade boy who was living in a small income fatherless family from the viewpoints of both sandplay theory and related literatures. The goal of the therapy was to lessen his difficulties under the free and protected space of sandplay therapy. This study comprised 59 sessions of sandplay therapy. The subject exhibited his situations in the initial parts of therapy(1~5, the preparation for war against enemies) by putting miniatures related to Egypt and by placing Indians who were keeping the house from enemies. In the intermediate sessions(6~47, holding a ceremony), he repeated burning rituals, played finding treasures, and exhibited both struggle and construction. In the final parts(48~59, integration), he showed integration by expressing the adaptation to the collective. This study indicated the effectiveness of sandplay therapy, because his maladjustments in both school and home were reduced.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• 제23권2호
• /
• pp.93-114
• /
• 2019

In this article, we introduce a finite difference method for solving the Navier-Stokes equations in rectangular domains. The method is proved to be energy stable and shown to be second-order accurate in several benchmark problems. Due to the guaranteed stability and the second order accuracy, the method can be a reliable tool in real-time simulations and physics-based animations with very dynamic fluid motion. We first discuss a simple convection equation, on which many standard explicit methods fail to be energy stable. Our method is an implicit Runge-Kutta method that preserves the energy for inviscid fluid and does not increase the energy for viscous fluid. Integration-by-parts in space is essential to achieve the energy stability, and we could achieve the integration-by-parts in discrete level by using the Marker-And-Cell configuration and central finite differences. The method, which is implicit and second-order accurate, extends our previous method [1] that was explicit and first-order accurate. It satisfies the energy stability and assumes rectangular domains. We acknowledge that the assumption on domains is restrictive, but the method is one of the few methods that are fully stable and second-order accurate.

• 시스템엔지니어링학술지
• /
• 제2권2호
• /
• pp.11-20
• /
• 2006

For systematic and effective achievement of Military R&D(Research and Development) processes and activities, information system which supports the concept of Systems Engineering is necessary. WISEMAN(Weapon System Information Integration for System Engineering and Management) is an information integration system, which can provide various kinds of interrelated application functions and assist the collaboration and concurrent engineering activities for weapon system R&D processes and activities. WISEMAN can manage the design information and configuration data of the target development products. It takes charge of the processes and histories about the product data, makes to share all the design information, and provides important application functions for R&D processes such as requirement management, product structure management, parts Management, documents and CAD drawing management, design change management, TDP(Technical Data Package) management etc., and in conjunction with these functions WISEMAN controls various effectivities of system configurations based on baselines and model information. WISEMAN has been used by ADD and Rotem Co. since developed.

• 공학교육연구
• /
• 제17권3호
• /
• pp.34-41
• /
• 2014

In distance education, use of proper software tools can greatly enhance student's attention and learning efficiency. In such software tools, offering diverse multimedia information is one of the most critical factors. However, integration and synchronization of the various media types has been relatively difficult parts of implementation. This paper proposes a prototype system that uses a metafile and event handling mechanism for the uniform treatment of various media types. This event-level integration and synchronization of multimedia makes the implementation relatively simple. With this approach, instructor's behaviors are automatically recorded, and the instructors can freely choose and show any type of multimedia contents while lecturing. Current commercial or non-commercial lecture management systems could incorporate this approach, so that the distance education market could be expanded with richer multimedia contents.

• International Journal of CAD/CAM
• /
• 제9권1호
• /
• pp.17-24
• /
• 2010

For several years, researchers have focused on improving the integration of the CAD, CAM and Analysis through a better communication between the various analysis tools. This tendency to integrate the CAD/Analysis and automation of the corresponding processes requires data sharing between the various tasks using an integrated product model. We are interested in this research orientation to CAD/CAM/Analysis integration by rebuilding the CAD model (BREP), starting from the Analysis results (deformed mesh). Because this problem is complex, it requires to be split into several complementary parts. This paper presents an original interoperability process between the CAD and CAE. This approach is based on a new technique of rebuilding the CAD surface model (Nurbs, Bezier, etc.) starting from triangulation (meshed surface) as a main step of the BREP solid model. In our work, the advantages of this approach are identified using a centrifugal pump example.

• 한국산업융합학회 논문집
• /
• 제19권1호
• /
• pp.42-49
• /
• 2016

This study proposes a non-contact inspective technology based robot vision system for Faulty Inspection of welding States and Parts Shape. The maine focus is real time implementation of the machining parts' automatic inspection by the robotic moving. For this purpose, the automatic test instrument inspects the precision components designator the vision system. pattern Recognition Technologies and Precision Components for vision inspection technology and precision machining of precision parts including the status and appearance distinguish between good and bad. To perform a realization of a real-time automation integration system for the precision parts of manufacturing process, it is designed a robot vision system for the integrated system controller and verified the reliability through experiments. The main contents of this paper, the robot vision technology for noncontact inspection of precision components and machinery parts is useful technology for FA.