• Journal of Electrical Engineering and Technology
• /
• v.13 no.1
• /
• pp.326-332
• /
• 2018

In this paper, the design process and the control method of the power conversion system (PCS) that consists of a bidirectional DC-DC converter and a 3-level T-type inverter for an energy storage system is presented. Especially the design method of the output LCL filter for a 3-lvel T-type inverter without complex mathematical process are proposed. The validity of the control method and design process in this paper are verified through simulation and experimental analysis.

• Proceedings of the KSRS Conference
• /
• 2008.10a
• /
• pp.220-223
• /
• 2008

A camera system for the satellite application performs the mission of observation by measuring radiated light energy from the target on the earth. As a development stage of the system, the signal level analysis by estimating the number of electron collected in a pixel of an applied CCD is a basic tool for the performance analysis like SNR as well as the data path design of focal plane electronic. In this paper, two methods are presented for the calculation of the number of electrons for signal level analysis. One method is a quantitative assessment based on the CCD characteristics and design parameters of optical module of the system itself in which optical module works for concentrating the light energy onto the focal plane where CCD is located to convert light energy into electrical signal. The other method compares the design\ parameters of the system such as quantum efficiency, focal length and the aperture size of the optics in comparison with existing camera system in orbit. By this way, relative count of electrons to the existing camera system is estimated. The number of electrons, as signal level of the camera system, calculated by described methods is used to design input circuits of AD converter for interfacing the image signal coming from the CCD module in the focal plane electronics. This number is also used for the analysis of the signal level of the CCD output which is critical parameter to design data path between CCD and A/D converter. The FPE(Focal Plane Electronics) designer should decide whether the dividing-circuit is necessary or not between them from the analysis. If it is necessary, the optimized dividing factor of the level should be implemented. This paper describes the analysis of the electron count of a camera system for a satellite application and then of the signal level for the interface design between CCD and A/D converter using two methods. One is a quantitative assessment based on the design parameters of the camera system, the other method compares the design parameters in comparison with those of the existing camera system in orbit for relative counting of the electrons and the signal level estimation. Chapter 2 describes the radiometry of the camera system of a satellite application to show equations for electron counting, Chapter 3 describes a camera system briefly to explain the data flow of imagery information from CCD and Chapter 4 explains the two methods for the analysis of the number of electrons and the signal level. Then conclusion is made in chapter 5.

• The Korean Journal of Applied Statistics
• /
• v.25 no.1
• /
• pp.215-223
• /
• 2012

Response surface methodology(RSM) is a very useful statistical techniques for improving and optimizing the product process. By this reason, RSM has been utilized extensively in the industrial world, particularly in the circumstances where several product variables potentially influence some quality characteristic of the product. In order to estimate the optimal condition of product variables, an experiment is being conducted defining appropriate experimental region. However, this experimental region can vary with the experimental circumstances and choice of a researcher. Response surface designs can be classified, according to the shape of the experimental region, into spherical and cuboidal. In the spherical case, the design is either rotatable or very near-rotatable. The central composite design(CCD)s widely used in RSM is an example of 5-level and spherical design. The cuboidal CCDs(CCDs with ${\alpha}=1$) is appropriate when an experimental region is cuboidal but this design dose not satisfy the rotatability as it is not spherical. Practically, a 3-level spherical design is often required in the industrial world where various level of experiments are not available. Box-Behnken design(BBD)s are a most popular 3-level spherical designs for fitting second-order response surfaces and satisfy the rotatability but the experimental region does not vary with the number of variables. The new experimental design with expanded experimental region can be considered if the predicting response at the extremes are interested. This paper proposes a new 3-level spherical RSM which are constructed to expand the experimental region together with number of product variables.

• Korean Journal of Computational Design and Engineering
• /
• v.16 no.4
• /
• pp.305-313
• /
• 2011

This paper proposes a method for reusing kinematic design data for virtual facilities, Making a virtual model of a facility involves two major activities: geometric design (virtual model visualization) and kinematic design that should be remodeled frequently whenever design changes occur, Conventionally, a virtual model of an automated facility focuses on the design level, which mainly deals with design verification, alternative comparison, and geometric model diagnosis, Although a design level model can be designed with the information of past models from PLM system, a simulation level model is not sufficient utilized to be reused for kinematic design purpose, We propose a method for reusing kinematic information of a past simulation model to cope with this problem, We use the concept or the 'center of mass', which is a point representing the mean position of the matter in a body or system. And we also use comparison method of a boundary box to identity which 3D objects have to be involved from the design model to a link structure that is contained in the simulation model. Because a proposed method only use not a historical approach but a geometrical approach, it is more effective to apply to the field.

• Korean Journal of Computational Design and Engineering
• /
• v.6 no.3
• /
• pp.157-168
• /
• 2001

The description of enterprise activities is the basis fur process improvement and information system building. To describe such activities, it is necessary to model the enterprise activities from the abstraction level to the implementation level in a stepwise and integrated form. For this reason, several modeling approaches have been proposed. However, most of them lacked the stepwise or integration aspects although some of them covered overall levels. This study proposes the hierarchical modeling approach for integrating the enterprise activity model from the abstraction level to the implementation level systematically. It is composed of five modeling levels such as function level, process level, task level, document workflow level, and event flow level. This study discusses the definition and characteristics of each level and compare our modeling frame with other modeling methodologies in case study.

• Journal of The Korea Institute of Healthcare Architecture
• /
• v.27 no.1
• /
• pp.17-34
• /
• 2021

Purpose: The purpose of this study was to find out the difference in the priority level of recognition for universal design application in public spaces by gender. Method: ANOVA(analysis of variance) and post-hoc test were conducted to determine the priority level of recognition and pattern for the disabled, non-disabled, and experts classified into males and females. Results: There was no gender difference in the comparison by sector for all males and females. However, in comparing of domains and facilities, women showed a higher level of recognition than men in the building sector and cross domain. When comparing space consumers and producers by dividing them into male and female groups, women showed a higher level of recognition than men in producers, but there was no gender difference between consumers. In comparison by sector, domain and facility, women producers also showed a higher level of recognition in the road sector, park and recreation sector, sidewalk domain, four-spaces in the park and recreation sector, and six-spaces in the building sector than men producers. Also, in the building sector, women producers and consumers showed a higher recognition level than men. Comparing the disabled, non-disabled people and experts by dividing them into male and female groups, in the case of non-disabled people and experts, women showed a higher level of recognition than men, while men showed a higher level of recognition than women in the disabled. In addition, there were differences in recognition patterns in many spaces and facilities by gender. Implications: This study is meaningful in comparing the differences in the priority level of recognition and patterns between men and women to apply universal design for people of all ages and both sexes.

• Fashion & Textile Research Journal
• /
• v.17 no.5
• /
• pp.718-730
• /
• 2015

This study investigated the correlation between the level of consistency in fashion show models' appearance and design concept through a statistical and qualitative analysis of the S/S Paris Collection 2014. The following conclusions have been drawn in this study. First, the percentage of models of color was very low in regards to the physical appearance of models; in addition, there was a higher percentage of Caucasian models for collections with a high level of consistency in models' physical appearance. Collections with a high percentage of models of color indicate more casual design concepts and the promotion of diversity in racial background is considered more effective for street fashion. Second, collections with a high level of consistency in models' physical appearance tend to control various elements that constitute a physical appearance through more detailed planning and stage direction. Third, there is a tendency to reinforce design concepts by creating a consistency in the overall physical appearance of models. This affirms that their physical appearance is determined by brand (i.e. designer) and is used to maximize a design concept delivery. The results of this study suggests that the physical appearance of models must be determined in line with the design concept versus detailed planning that must consider audience perspectives as well as adjust the show's length and the interval between each model appearing on the stage.

• Journal of Korean Association for Spatial Structures
• /
• v.1 no.1 s.1
• /
• pp.143-155
• /
• 2001

Generally, truss design has been determined by the designer's experience and intuition. But if we perform the most economical structural design we must consider not only cross-sections of members but also configurations(howe, warren and pratt types etc.) of single truss as the number of panel and truss height. The purpose of this study is to develope automated optimum design techniques for steel truss structures considering cross-sections of members and shape of trusses simultaneously. As the results, it could be possible to find easily the optimum solutions subject to design conditions at the preliminary structural design stage of the steel truss structures. In this study, the objective function is expressed as the whole member weight of trusses, and the applied constraints are as stresses, slenderness ratio, local buckling, deflection, member cross-sectional dimensions and truss height etc. The automated optimum design algorithm of this study is divided into three-level procedures. The first level on member cross-sectional optimization is performed by the sequential unconstrained minimization technique(SUMT) using dynamic programming method. And the second level about truss height optimization is applied for obtaining the optimum truss height by three-equal interval search method. The last level of optimization is applied for obtaining the optimum panel number of truss by integer programming method. The algorithm of multi-level optimization programming technique proposed in this study is more helpful for the economical design of plane trusses as well as space trusses.

• Proceedings of the IEEK Conference
• /
• 2000.06b
• /
• pp.173-176
• /
• 2000

Silicon semiconductor technology agree that the number of transistors on a chip will keep growing exponentially, and it is pushing technology toward the System-On-Chip. In SoC Design, Specification at system level is key of success. Executable Specification reduce verification time. This Paper describe the design of IMDCT for MPEG Audio Decoder employing system-level design methodology and Executable Specification Methodology in the VHDL simulator with FLI environment.

• Proceedings of the Korean Institute of Interior Design Conference
• /
• 1999.04a
• /
• pp.11-15
• /
• 1999

By taking an ecological approach, The purpose of this study was to 1. analyze the existing literary work about design directives for the elderly housing, 2. case study about actual housing conditions of elderly people, and analyze the level of satisfaction and level of requirement about housing environment by Korean elderly, By integrating the above three, suggested foundational data arranging the appropriate housing design directives pertaining to Korea's catual circumstances.