• The Journal of the Korea Contents Association
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• v.20 no.12
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• pp.671-680
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• 2020

Today, if you don't reflect trends in developing new content crafts, you can't succeed in marketing. This is because the trend is the driving force that leads to the needs of consumers that come and go temporarily. The current market is changing and wants new lifestyle trends. As a trend of such latent desire, the purpose is to develop high-value-added interior vases using rice cake patterns and ceramic complexes. In the manufacturing method, the first rice cake patterns writing tool is stamped at a different angle from the top of the toremi board (a new term created above) written in the process of the pot work. A cylinder is made of a second potter's wheel, and after the outer wall is double-flavored, the cylinder is quickly rotated to be extended by pushing it from inside to outside by hand. The purpose of this vase is to develop a decorative vase with high added value by experimenting with various geometric patterns that are dismantled vertically and horizontally at a high speed with the static rice cake pattern stamped on the third, and then utilizing the various rice cake patterns developed in this way as the shape of a jar.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.2
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• pp.117-123
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• 2012

This paper discusses two different techniques used to measure the mechanical properties of thin films: the bulge test and the nanoindentation test. In the bulge test, a uniform pressure is applied to one side of the film. Measurement of the membrane deflection as a function of the applied pressure allows one to determine the mechanical properties such as Young's modulus, and the residual stress. A nanoindentation test is performed by pushing an indenter tip into the specimen and then withdrawing it, and then recording the indentation force as a function of the indenter position. A modified King's model is used to estimate the mechanical properties of the thin film in order to avoid the effects of the substrate layers. A combination of both the bulge test and the nanoindentation test can determine both Young's modulus and Poisson's ratio simultaneously.

• Journal of Advanced Navigation Technology
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• v.26 no.5
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• pp.312-318
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• 2022

Currently, the Republic of Korea is facing the problem of a decrease in military service resources due to the demographic cliff, and is pursuing military restructuring and changes in the military force structure in order to respond to this. In this situation, the Army is pushing forward the deployment of a drone-bot combat system that will lead the future battlefield. The battlefield of the future will be changed into an integrated battlefield concept that combines command and control, surveillance and reconnaissance, and precision strike. According to these changes, unmanned combat system, including dronebots, will be widely applied to combat situations that are high risk and difficult for humans to perform in actual combat. In this paper, as one of the countermeasures to these changes, autonomous behavior software with a BDI architecture-based decision-making system was developed. The autonomous behavior software applied a framework structure to improve applicability to multiple models. Its function was verified in a PC-based environment by assuming that the target UAV is a battalion-level surveillance and reconnaissance UAV.

• Journal of The Korean Association For Science Education
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• v.36 no.6
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• pp.851-866
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• 2016

The purpose of this study is to investigate pre-service elementary teachers' views of the law of action-reaction by examining their degrees of understanding and Typically-Perceived-Situations (TPS). Data were collected from 177 Grade 3 pre-service elementary teachers. The results of analyzing these data show: First, the participants did not sufficiently understand about the law of action-reaction, and their degrees of understanding were different depending on the situation provided in the questionnaire. Second, in relation to the TPSs of the law of action-reaction, the participants thought of irrelevant situations to the law of action-reaction such as "a situation generated by inertia" as well as commonly relevant ones such as "a person pushing a wall", and had somewhat biased TPSs in terms of 'action type' and 'result motion type' of action-reaction. Finally, several suggestions on the science education for promotion of understanding about the law of action-reaction were given.

• Composites Research
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• v.14 no.5
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• pp.1-11
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• 2001

The particulates reinforced metal matrix composites(PMMC) have a number of interesting mechanical properties. including high strength and good resistance to wear at high temperature and low thermal expansion. The equipment structure to obtain the homogeneous distribution in composites are proposed for the continuous pouring of reinforcement at the desired temperature. The particulates reinforced metal matrix composites(A357/SiCp) were fabricated by the process of the combined stirring method with the various fabrication process. The combined stirring method to niform distribution of particle is consisted of two stirring force both electro-magnetic stirring generated from induction heating and mechanical stirring with graphite stirrer. PMMC billets were fabricated with the volume fractions ranged from 0% to 20% and particle sizes ranged from 14${\mu}{\textrm}{m}$ to 25${\mu}{\textrm}{m}$. It is important to cont the size of primary $\alpha$-Al solid particles because it could become the cause of the particle pushing or capture phenomena from the fact that secondary dendrite arm spacing size depends on the cooling rate during the solidification in hypoeutectic Al-Si alloy. Therefore, the effect of primary $\alpha$-Al on the reinforcement distribution in matrix alloys has been investigated. The microstructure of PMMC fabracated with various volume fractions(0%, 10%, and 20%) and particle size were observed.

• Earthquakes and Structures
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• v.8 no.5
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• pp.1255-1276
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• 2015

The importance of considering soil-structure interaction effect in the analysis and design of RC frame buildings is increasingly recognized but still not penetrated to the grass root level owing to various complexities involved. It is well established fact that the soil-structure interaction effect considerably influence the design of multi-storey buildings subjected to lateral seismic loads. The shear walls are often provided in such buildings to increase the lateral stability to resist seismic lateral loads. In the present work, the linear soil-structure analysis of a G+5 storey RC shear wall building frame resting on isolated column footings and supported by deformable soil is presented. The finite element modelling and analysis is carried out using ANSYS software under normal loads as well as under seismic loads. Various load combinations are considered as per IS-1893 (Part-1):2002. The interaction analysis is carried out with and without shear wall to investigate the effect of inclusion of shear wall on the total and differential settlements in the footings due to deformations in the soil mass. The frame and soil mass both are considered to behave in linear elastic manner. It is observed that the soil-structure interaction effect causes significant total and differential settlements in the footings. Maximum total settlement in footings occurs under vertical loads and inner footings settle more than outer footings creating a saucer shaped settlement profile of the footings. Each combination of seismic loads causes maximum differential settlement in one or more footings. Presence of shear wall decreases pulling/pushing effect of seismic forces on footings resulting in more stability to the structures.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.473-480
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• 2014

Upon setting up a dedicated plastic greenhouse for tomato cultivation developed by the Rural Development Administration on the Gyehwa reclaimed land, this study was aimed at analyzing the problems can be occurred in the installation of plastic greenhouse on reclaimed lands as well as finding out solutions for improvement. A relatively cheaper wooden pile was used in the installation in order to supplement the soft ground conditions. Based on the results of ground investigation of the installation site, both the allowable bearing capacity and pulling resistance of the wooden pile with a diameter of 150 mm and a length of 10 m were computed and came out to be 30.645 kN. It was determined that the values were enough to withstand the maximum compressive force (17.206 kN) and the pullout force (20.435 kN) that are generally applied to the greenhouse footing. There are three problems aroused in the process of greenhouse installation, and the corresponding countermeasures are as follow. First, due to the slightly bent shape of the wooden pile, there were phenomenon such as deviation, torsion, and fracture when driving the pile. This could be prevented by the use of the backhoe (0.2) rotating tongs, which are holding the pile, to drive the pile while pushing to the direction of the driving and fixing it until 5 m below ground and applying a soft vibrating pressure until the first 2 m. Second, there exists a concrete independent footing between the column of the greenhouse and the wooden pile driven to the underground water level. Since it is difficult to accurately drive the pile on this independent footing, the problem of footing baseplate used to fix the column being off the independent footing was occurred. In order to handle with this matter, the diameter of the independent footing was changed from 200 mm to 300 mm. Last, after films were covered in the condition that the reinforcing frame and bracing are not installed, there was a phenomenon of columns being pushed away by the strong wind to the maximum of $11m{\cdot}s^{-1}$. It is encouraged to avoid constructions in winter, and the film covering jobs always to be done after the frame construction is completely over. The height of the independent footing was measured for 9 months after the completion of the greenhouse installation, and it was found to be within the margin of error meaning that there was no subsidence. The extent to the framework distortion and the value of inclinometers as well showed not much alteration. In other words, the wooden pile was designed to have a sufficient bearing capacity.

• Journal of Navigation and Port Research
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• v.42 no.3
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• pp.237-244
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• 2018

When underwater rubble leveling work is carried out by a robot, real-time information on the topography around the robot is required for remote control. If the topographical information with respect to the current position of the robot is displayed as a 3D graphic image, it allows the operator to plan the working schedules and to avoid accidents like rollovers. Up until now, the topographical recognition was conducted by multi-beam sonars, which were only used to assess the quality before and after the work and could not be used to provide real-time information for remote control. This research measures the force delivered to the bucket which presses the mound to determine whether contact is made or not, and the contact position is calculated by reading the cylinder length. A variable bang-bang control algorithm is applied to control the heavy robot arms for the positioning of the bucket. The proposed method allows operators to easily recognize the terrain and intuitively plan the working schedules by showing relatively 3-D gratifications with respect to the robot body. In addition, the operating patterns of a skilled operator are programmed for raking, pushing, moving, and measuring so that they are automatically applied to the underwater rubble leveling work of the robot.

• Journal of Navigation and Port Research
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• v.44 no.6
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• pp.439-446
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• 2020

The IMO has adopted emission standards through Annex VI of the International Convention for the Prevention of Pollution from Ships (MARPOL) that strictly prohibit the use of bunker C oil for vessels. In this study, we have adopted the turret-moored Floating LNG-Bunkering Terminal (FLBT) which is designed to receive the LNG from LNGCs and transfer it to LNG-bunkering shuttles in side-by-side moored condition. Numerical analyses were carried out using the high-order boundary-element method for four vessels at various relative distances. Mean wave drift forces were compared in an operational sea state. A model test was performed in the ocean engineering basin at the Korea Research Institute of Ships & Ocean Engineering (KRISO) to verify the safety of the berthing/unberthing operation. In the model test, a jig was designed to simulate tug boats pushing or pulling the bunkering vessels, so that the friction force of the g operation was not affected. Safety depended on the environmental direction, with more stable operation possible if the heading-control function of FLBT is applied to avoid beam-sea conditions.

• Journal of Information Technology Applications and Management
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• v.13 no.3
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• pp.29-57
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• 2006

Small and medium-sized companies (SMEs) face a number of different kinds of barriers to adopt information technology, including the lack of information, limited financial and technical resources, and absence of the well-trained work force in the realm of information technology. But application service provider (ASP)enables these SMEs to informatize. This paper is focused on studying the cases of the adoption and use of the ASP-based ERP systems that 7 SME shad adopted. The factors that influence the adoption and use of SMEs' ASP-based ERP systems are divided into the user companies that adopted the systems, the systems vendors, and environment. From the viewpoint of the user company, the successful adoption and use of the systems is significantly influenced by the clear motive of adopting the systems, the financial readiness, and the strong intention of CEO for pushing ahead with e-Business. From the systems vendor, it is influenced by the technical expertise of the vendor, the knowledge of the user company, and the experience of the systems development. From the perspective of environment, it is influenced by the push from the players in the value chains. The companies that had adopted the ASP-based ERP systems and that had extended the level of systems use had the benefits through reducing the cost, improving the internal business process, and achieving the learning and growth of the organization.