• Journal of Platform Technology
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• v.9 no.4
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• pp.60-70
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• 2021

This paper proposes a method capable of stably tracking the coordinates of a patterned laser image in a curved screen shooting system using two or more channels of multiple cameras. This method can track and acquire target points very effectively when applied to a multi-screen shooting method that can replace the HMD shooting method. Images of curved screens with severe deformation obtained from individual cameras are corrected through image normalization, image binarization, and noise removal. This corrected image is created and applied as an Euclidean space map that is easy to track the firing point based on the matching point. As a result of the experiment, the image coordinates of the pattern laser were stably extracted in the curved screen shooting system, and the error of the target point position of the real-world coordinate position and the broadband Euclidean map was minimized. The reliability of the proposed method was confirmed through the experiment.

• International Journal of Fluid Machinery and Systems
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• v.3 no.4
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• pp.309-314
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• 2010

Stainless steel stamping multistage pump has become the mainstream of civil multi-stage pump. Combined with the technological features of stamping and welding pump, the studies of design for hydraulic parts of pump were come out. An $L_{18}$（$3^7$）orthogonal experiment was designed with seven factors and three values including blade inlet angle, impeller outer diameter, guide vane blade number, etc. 18 plans were designed. The two stage of whole flow field on stainless steel stamping multistage pump at design point for design was simulated by CFD. According to the test result and optimization design with experimental research, the trends of main parameters which affect hydraulic performance were got. After being manufactured and tested, the efficiency of the optimal model pump reaches 61.36% and the single head is more than 4.8 m. Compared with the standard efficiency of 53%, the design of the stainless steel stamping pump is successful. The result would be instructive to the design of Stainless steel stamping multistage pump designed by the impeller head maximum approach.

• Steel and Composite Structures
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• v.51 no.2
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• pp.173-183
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• 2024

This study investigates a new seismic retrofit system that utilizes rotational friction dampers and axial springs. The retrofit system involves a steel frame with rotational friction dampers (RFD) at beam-column joints and linear springs at the corners, providing energy dissipation and self-centering capabilities to existing structures. The axial spring acts as a self-centering mechanism that eliminates residual deformations, while the friction damper mitigates seismic damage. To evaluate the seismic performance of the proposed retrofit system, a series of cyclic loading tests were carried out on a steel beam-column subassembly equipped with the proposed devices. An analytical model was then developed to validate the experimental results. A performance point ratio (PPR) was presented to optimize the design parameters of the retrofit system, and a performance-based seismic design strategy was developed based on the PPR. The retrofit system's effectiveness and the presented performance-based design approach were evaluated through case study models, and the analysis results demonstrated that the developed retrofit system and the performance-based design procedure were effective in retrofitting structures for multi-level design objectives.

• The Transactions of the Korea Information Processing Society
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• v.7 no.6
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• pp.1737-1745
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• 2000

In the last decade, considerable research effort has been studied ot multi-dimensional GIS and many spatiotemporal operations and query languages have been proposed. Many of them have focused on designing of operation, which process with data that is valid at current point in time. But, research that studied to updata operation that updates or inserts the past data is very rare. This paper designs an update operation and an insertion operation for integrity of past data of multi-dimensional GIS, and propose a new data model for efficient processing of the operations.

• Journal of the Korea Society of Computer and Information
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• v.20 no.2
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• pp.99-112
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• 2015

Datum point for displaying location and altitude of point has being advantage usefully in various measurement parts. However, datum point has been increasing loss cases owing to weather changes and stratum changes and neglecting meaninglessly. In this paper, we design and implement a multi electronic measurement system monitoring software with functions such as include maximize utilization of existing measurement datum system as well as collected various environment data and detection stratum changes of surround area. Proposed software is implemented to support that reusability and extensibility of software using object oriented modeling method. Our software supports a GUI for electronic measurement datum point administrator as well as for web user and mobile user. Our system can support a graph GUI for various data analysis and reposition in realtime to database that measured location information and various sensing information to prevent loss of electronic measurement datum point and to detected stratum changes. In addition, we include a QR code and RFID recognition function. Finally, we suggest performance evaluation result to confirm stratum changes detection and GPS location error rate.

• Ocean Systems Engineering
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• v.14 no.1
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• pp.17-52
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• 2024

In this paper, the authors explore the modeling and control of a point absorber wave energy converter, which is connected to the electric grid via a power converter that is based on a linear permanent magnet synchronous generator (LPMSG). The device utilizes a buoyant mechanism to convert the energy of ocean waves into electrical power, and the LPMSG-based power converter is utilized to change the variable frequency and voltage output from the wave energy converter to a fixed frequency and voltage suitable for the electric grid. The article concentrates on the creation of a predictive control system that regulates the speed, voltage, and current of the LPMSG, and the modeling of the system to simulate its behavior and optimize its design. The predictive model control is created to guarantee maximum energy output and stable grid connection, using Matlab Simulink to validate the proposed strategy, including control side generator and predictive current grid-side converter loops.

• Journal of Ocean Engineering and Technology
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• v.26 no.4
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• pp.77-85
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• 2012

A study was performed on the design of a mooring line to maintain the position of a floating WEC (wave energy conversion) system. The procedure to design a mooring line is set up and the safety of the designed mooring system is evaluated using commercial software, Orcaflex. The characteristics curve for one line is analyzed to determine the properties and pretension of a mooring line. While considering the ocean environmental condition and importance of a floating WEC system, a multi-line layout is determined. A 4-point mooring system with 4 lines shows the instability in the yaw motion of the floating WEC system under a designed ocean environmental condition. The redesigned 4-point mooring system with 8 lines is found to be safe on the condition of a harsh ocean environment. The floating WEC system with the redesigned mooring system also shows stable motion in surge and pitch under operating conditions. From a parametric study on the mooring line length, the extreme value of the mooring line tension is found to be very sensitive to the pretension and length of mooring line. The results of this study can contribute to the establishment of a design procedure for mooring lines.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.36 no.2
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• pp.13-24
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• 2020

This study derives the characteristics of the private external space planning in multi-family housing through the analysis of the good case built after 2000 in Europe. First, the cases were categorized into block or block perimeter, linear and point type to examine the relationship between the type of building in urban context and the location of private external space. By block or block perimeter and linear type, private external spaces are planned in the inner courtyards or open space between buildings used as common space for residents, inducing communications between neighbors. And the direction of private external space depends on the arrangement of the building mass in urban context. In the classification as point type, there are many cases, where private external spaces are arranged in all directions, connected almost all interior spaces. Second, based on the above results, the planned characteristics of the private external space are derived by dividing it into three categories: intermediated space between inside and outside, intermediate space between private and public /individual and collective space and the identity of the intermediate space. (1) In most cases, direction, size of enclosed area and location of private extern space is designed to fit the surrounding context, so residents can perceive as much of the assets of the surrounding environment as possible, and it can be used as an extended area of living space. In another cases, it is divided into various sub-areas to experience the spatial transition from inside to outside or vice versa. 2) The private external space, which is placed in a courtyard or in a collective open space, is partially enclosed and blocked, allowing interaction with the neighbors without pressure. Along the street, they are designed to allow residents to experience the vitality of the city and to be formative element of the facade, which could confidently reveal the lifestyle and taste of residents. 3) By some of point types, which facade is three-demensional layer as a habitable external space, the private external space is very flexible for use. This intermediate space is composed of diverse spaces for various needs, or it has generous size with positional conditions connected with all interior spaces to be used multi-functional.

• International Journal of Control, Automation, and Systems
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• v.4 no.6
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• pp.669-681
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• 2006

In this work, a new method of design adaptive controllers for SISO systems based on multiple models and switching is presented. The controller selects the model from a given set, according to a switching rule based on output prediction errors. The goal is to design, at each sample instant, a predictive control law that ensures the robust stability of the closed-loop system and achieves the best performance for the current operating point. At each sample the proposed control scheme identifies a set of linear models that best characterizes the dynamics of the current operating region. Then, it carries out an automatic reconfiguration of the controller to achieve the best possible performance whilst providing a guarantee of robust closed-loop stability. The results are illustrated by simulations a nonlinear continuous and stirred tank reactor.

• Journal of the Korea Fashion and Costume Design Association
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• v.3 no.1
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• pp.93-115
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• 2001

Korean textile industry is faced a turning point, And the culture of a country itself is getting a main competetive items. Therefore, this study is focused upon developing fashion items of Korean image. For this study purpose, I carried out literature review and questionnaires were surveyed with 129 women, to see how Korean women interested in costume are conscious of Korean image and the way to develop Korean image fashion items. The study results are as follows. 1. To Koreans, the elements of Korean image were Hanbok(Korean traditional cloths) and Saeckdong(traditional multi-coloured stripes), but to foreigners they were national image. 2. To develop competetive fashion items of Korean image, I recommend as follows. - set up a typical key-word of Korean image - promote top designer - globalization of Hanbok - take advantage of 2002 Wold Cup - bring Korean image fashion into vogue to the younger from domestic to abroad - make Korean image into universal fashion - start with accessories, hats, bags, scarves