• Journal of applied mathematics & informatics
• /
• v.30 no.5_6
• /
• pp.759-772
• /
• 2012

In this paper, semi-infinite constrained programming, a class of constrained nonsmooth optimization problems, are transformed into unconstrained nonsmooth convex programs under the help of exact penalty function. The unconstrained objective function which owns the primal-dual gradient structure has connection with $\mathcal{VU}$-space decomposition. Then a $\mathcal{VU}$-space decomposition method can be applied for solving this unconstrained programs. Finally, the superlinear convergence algorithm is proved under certain assumption.

• Journal of Digital Convergence
• /
• v.12 no.12
• /
• pp.513-520
• /
• 2014

Since the beginning of history, men have done mimesis and produced illusion and succeeded art and culture instinctually. The subject which mention above included the object which can order and space around that. Perspective which began the Renaissance age was dominant way about understanding space in western history and it made modern visual system. Direction way of space which based perspective is changed as horizontal data included multi-layer structure in digital media age. This character make us possible to represent the space more efficiently. So we must have pay attention the direction way of space based on digital media, because it has meaning to show human value beyond a methodology of visual art culture.

• ETRI Journal
• /
• v.28 no.1
• /
• pp.9-16
• /
• 2006

In this paper, we analyzed and measured the electrical crosstalk characteristics of a 1.25 Gbps triplexer module for Ethernet passive optical networks to realize fiber-tothe-home services. Electrical crosstalk characteristic of the 1.25 Gbps optical triplexer module on a resistive silicon substrate should be more serious than on a dielectric substrate. Consequently, using the finite element method, we analyze the electrical crosstalk phenomena and propose a silicon substrate structure with a dummy ground line that is the simplest low-crosstalk layout configuration in the 1.25 Gbps optical triplexer module. The triplexer module consists of a laser diode as a transmitter, a digital photodetector as a digital data receiver, and an analog photodetector as a cable television signal receiver. According to IEEE 802.3ah and ITU-T G.983.3, the digital receiver and analog receiver sensitivities have to meet -24 dBm at $BER=10^{-12}$ and -7.7 dBm at 44 dB SNR. The electrical crosstalk levels have to maintain less than -86 dB from DC to 3 GHz. From analysis and measurement results, the proposed silicon substrate structure that contains the dummy line with $100\;{\mu}m$ space from the signal lines and 4 mm separations among the devices satisfies the electrical crosstalk level compared to a simple structure. This proposed structure can be easily implemented with design convenience and greatly reduce the silicon substrate size by about 50 %.

• Journal of Korea Multimedia Society
• /
• v.23 no.4
• /
• pp.574-580
• /
• 2020

Stress induces change to the body functions and causes chronic problems such as worsening a disease. Thus, humans want to evade anxiety and would try any means to reduce stressful situations. Generally, a person would handle their stress by either regulating their emotions or merely coping with the situation, for which the former is most widely used. Our research aims to effectively reduce stress by using the emotional response structure developed by Plutichik and the vitalization method. We extracted the relevant components of the stress-reduction method that would be applicable in any space using digital technologies such as sensors, IoT, and augmented reality. An architect or designer may incorporate these structural components into any structure to effectively reduce people's stress. The research aims to provide a new perspective of architectural space and to show applications of the stress-reducing architectural spaces, which should also fulfill the people's needs. Further research is needed to develop an automatic system to utilize spatial components more effectively.

• Proceedings of the Korean Institute of Interior Design Conference
• /
• 2006.05a
• /
• pp.65-66
• /
• 2006

The motor show is the most popular show in domestic exhibitions. It provides many interesting events and exhibition programs from small parts of the car to luxury sedans. It should be spatially designed for not only display programs but also various other programs such as concerts or events. And it needs to approach strategic and complex plans for unique stand design because of a great number of visitors' safety and accomodation, and competition with other companies. S motor is the company of middle standing, producing the most luxurious sedans and SUVs. I had to find a display and space composition way to harmonize with luxurious sedans and outdoor vehicles in a booth. The booth had to be distinctive and unique inspite of relatively small and handicaped area compared with other companies' booths. So I designed two major plans; ceiling structure covered whole booth space and office space for staff. These plans could get completely majesty and unique design for booth, events and other programs. And the structure of booth was minimalized for visitors' safety and accomodation in great event time.

• Journal of information and communication convergence engineering
• /
• v.3 no.1
• /
• pp.49-55
• /
• 2005

This study is to suggest a visualization technique to display the relations of associated data in an optimal way when trying to display the whole data on a limited space by dealing with a large amount of data with linked information. For example, if you track an IP address through several steps and display the data on a screen, or if you visualize the human gene information on a 3-dimensional space, then it becomes even easier to understand the data flow in such cases. In order to simulate the technique given in this study, the given algorithm was applied to a large number of nodes made in a random fashion to optimize the data and we visually observed the result. According to the result, the technique given in this study is more efficient than any previous method in terms of visualization and utilizing space and allows to more easily understand the whole structure of a node because it consists of sub-groups.

• Journal of Mechanical Science and Technology
• /
• v.15 no.10
• /
• pp.1356-1368
• /
• 2001

In this paper, the model reference adaptive control (MRAC) of a flexible structure is investigated. Any mechanically flexible structure is inherently distributed parameter in nature, so that its dynamics are described by a partial, rather than ordinary, differential equation. The MRAC problem is formulated as an initial value problem of coupled partial and ordinary differential equations in weak form. The well-posedness of the initial value problem is proved. The control law is derived by using the Lyapunov redesign method on an infinite dimensional filbert space. Uniform asymptotic stability of the closed loop system is established, and asymptotic tracking, i. e., convergence of the state-error to zero, is obtained. With an additional persistence of excitation condition for the reference model, parameter-error convergence to zero is also shown. Numerical simulations are provided.

• Journal of Digital Convergence
• /
• v.17 no.11
• /
• pp.225-232
• /
• 2019

This study proposes a temporary residential prefab modular structure to provide residential space to displaced people after a disaster. Patent cases related to prefab structures are collected for related design implementations, and classified. Space in temporary residential prefab modular structures must consider factors such as "Expandability", "Assembly and Disassembly", "Built-in Structure", and "Energy Efficiency", and the cases are classified into "Detailed Assembly Modular Type", "Modular Expandable Type", and "Space Unit Expandable Type". Overseas patents cases will be collected and analyzed in future studies for providing the efficient way for mass production for the lowest production cost.

• Journal of the Korean Society of Industry Convergence
• /
• v.20 no.2
• /
• pp.133-140
• /
• 2017

This paper is a study of the central structural unit model of the sandwich core structure. The applied model is based on the honeycomb structure formed by the truss, the H-shaped honeycomb structure formed by adding the truss of H shape to the space of the center portion, and the honeycomb structure formed by the plate. Applied material property is AISI 304 stainless steel, which has cost effectiveness and easy to get near place. The truss diameter of the model is three different type: 1mm, 2mm and 3mm. ABAQUS software is obtained to do the analysis and applied test is quasi-static loading. Boundary conditions for the analysis are that vertical direction loading at top place without any rotation and bottom surface is fixed. The test results show that the H-truss model has the highest stiffness and yield strength. Therefore, it is hoped that more and more researching for the development of a unit model in sandwich core structure has been investigating and that the developed sandwich core model can be applied into various industrial fields such as mechanical or aerospace industries.

• Design Convergence Study
• /
• v.16 no.6
• /
• pp.59-74
• /
• 2017

Louis Sullivan insisted, "Form follows function." Functionality is one of the most fundamental elements for users to use product or space, and "function" in space and architecture has the meaning of the most important factor in determining its form. In this way, from the viewpoint of "Functionalism," the research selected Toyo Ito to see how important elements pursued by Functionalism are related to his forms of creation. Small residential space projects of Toyo Ito from the early 1970s to the present are selected, so that the structure, material and space type of space and architecture can easily grasped and analyzed. Space and architectural structures and surfaces were classified into the characteristics of materials and classified according to the strength of openness of space. As a result, the space and architecture that pursue the function use a method that can maximize the efficiency of the function while excluding the whole decoration in order to highlight the function. The characteristics found in Toyo Ito's small-scale residential space can be defined as the formalization and simplification of the form, the openness of space, and the versatility of each element.