• Steel and Composite Structures
• /
• v.46 no.2
• /
• pp.237-252
• /
• 2023

The article describes the development of a novel dissipative bracing connection device (identified by the acronym DRBrC) for concentrically braced frames in steel and composite structures. The origins of the device trace back to the seminal work of Kelly, Skinner and Heine (1972), and, more directly related, to the PIN-INERD device, overcoming some of its limitations and greatly improving the replaceability characteristics. The connection device is composed of a rigid housing, connected to both the brace and the beam-column connection (or just the column), in which the axial force transfer is achieved by four-point bending of a dissipative pin. The experimental validation stages, presented in detail, consisted of a preliminary testing campaign, resulting in successive improvements of the original device design, followed by a systematic parametric testing campaign. That final campaign was devised to study the influence of the constituent materials (S235 and Stainless Steel, for the pin, and S355 and High Strength Steel, for the housing), of the geometry (four-point bending intermediate spans) and of the loading history (constant amplitude or increasing cyclic alternate). The main conclusions point to the most promising DRBrC device configurations, also presenting some suggestions in terms of the replaceability requirements.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.35 no.5
• /
• pp.16-28
• /
• 2007

In this study, the implications for landscape architecture in the restoration Project of Cheonggyecheon will be shown through the analysis of factors for landscape architect scheme modification. The method of study consists of theoretical study, analysis of the plan and design of landscape architecture of the restoration project of Cheonggyecheon, and deduction of implications thereof. The controversial feints included the many difficulties in realizing the productive design of landscape architecture due to the selective collecting of public opinion and the problems of settling the complications, the design limit of the turnkey and MA systems, the lack of hydraulic knowledge and technology and the shortage of vegetation monitoring data and experimental materials. The alternative proposals are as follows: 1) there should be agreement between the government organization and the civil group, 2) in the turnkey bidding for the river restoration projects, the river restoration design based on the volume divided into some parts should be reconsidered in order to maintain consistency in the total design, 3) in order to maintain consistency in the planning policies, MA designs should also be introduced and applied from the first stage of the project through its completion, and 4) data such as the safe water level in case of flooding for the facilities and the vegetation and data in connection with the ecological restoration of river should be accumulated. If these controversies are not settled effectively, the river restoration project will be delayed due to complications with the citizens and wasted time and effort will result from the frequent design changes. In addition, landscape architecture in this kind of restoration project is bound to decrease in the future due to frequent changes in the hydraulic-centered design.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.52 no.1
• /
• pp.32-39
• /
• 2015

The voice communications with wireless backbone based networks are evolving into a packet switching VoIP systems. In those networks, a call processing scheme is required for management of subscribers and connection between them. A VoIP service scheme for those systems requires reliable subscriber management and connection establishment schemes, but the conventional call processing schemes based on the centralized server has lack of reliability. Thus, the mutual-backup architecture of SIP-servers is required to ensure efficient subscriber management and reliable VoIP call processing capability, and the synchronization and call processing schemes should be changed as the architecture is changed. In this paper, a mutual-backup architecture of SIP-servers is proposed for wireless backbone based networks. A message format for synchronization and information exchange between SIP servers is also proposed in the paper. This paper also proposes a FSM scheme for the fast call processing in unreliable networks to detect multiple servers at a time. The performance analysis results show that the mutual backup server architecture increases the call processing success rates than conventional centralized server architecture. Also, the FSM scheme provides the smaller call processing times than conventional SIP, and the time is not increased although the number of SIP servers in the networks is increased.

• Structural Engineering and Mechanics
• /
• v.11 no.5
• /
• pp.469-484
• /
• 2001

A new beam system comprising two cantilever stems and an interspan composite beam has been developed and its design philosophy is described in this paper. The system provides the equivalent of a semi-continuous beam without the requirement to calculate the moment rotation capacity of the beam-to-column connection. The economy of braced frames using the system has been investigated and compared with simple, continuous or semi-rigid systems. It is shown that the costs of the proposed system are similar to the semi-rigid system and cheaper than both the simply supported and rigid beam systems. Two tests have been carried out on 6 meter span beams, which also incorporated an asymmetric flange steel section. The behaviour of the system is presented and the test results are compared with those obtained from the theory.

• ETRI Journal
• /
• v.39 no.6
• /
• pp.859-865
• /
• 2017

This paper presents a method for determining the optimum active-area width (OAW) of solar cells in a module architecture. The current density-voltage curve of a reference cell with a narrow active-area width is used to reproduce the current density profile in the test cell whose active area width is to be optimized. We obtained self-consistent current density and electric potential profiles from iterative calculations of both properties, considering the distributed resistance of the contact layers. Further, we determined the OAW that yields the maximum efficiency by calculating efficiency as a function of the active-area width. The proposed method can be applied to the design of the active area of a dye-sensitized solar cell in Z-type series connection modules for indoor and building-integrated photovoltaic systems. Our calculations predicted that OAW increases as the sheet resistances of the contact layers and the intensity of light decrease.

• International Journal of Concrete Structures and Materials
• /
• v.11 no.2
• /
• pp.185-197
• /
• 2017

In this study, we propose a new equation that evaluates the shear strength of beam-column connections in reinforced concrete and steel beam (RCS) composite materials. This equation encompasses the effect of shear keys, extended face bearing plates (E-FBP), and transverse beams on connection shear strength, as well as the contribution of cover plates. Mobilization coefficients for beam-column connections in the RCS composite system are suggested. The proposed model, validated by statistical analysis, provided the strongest correlation with test results for connections containing both E-FBP and transverse beams. Additionally, our results indicated that Architectural Institute of Japan (AIJ) and Modified AIJ (M-AIJ) equations should be used carefully to evaluate the shear strength for connections that do not have E-FBP or transverse beams.

• Journal of information and communication convergence engineering
• /
• v.20 no.3
• /
• pp.160-165
• /
• 2022

This paper proposes an efficient method of reconstructing interconnections when the terminals of each plane change in real-time situations where randomly divided planes are interconnected. To connect all terminals when the terminals of each plane are changed, we usually reconstruct the interconnections between all terminals. This ensures a minimum connection length, but it takes considerable time to reconstruct the interconnection for the entire terminal. This paper proposes a solution to obtain an optimal tree close to the minimum spanning tree (MST) in a short time. The construction of interconnections has been used in various design-related areas, from networks to architecture. One of these areas is an ad hoc network that only consists of mobile hosts and communicates with each other without a fixed wired network. Each host of an ad hoc network may appear or disappear frequently. Therefore, the heuristic proposed in this paper may expect various cost savings through faster interconnection reconstruction using the given information in situations where the connection target is changing.

• ETRI Journal
• /
• v.45 no.3
• /
• pp.433-447
• /
• 2023

Critical issues such as connection congestion, long transmission delay, and packet loss become even worse during epidemic, disaster, and so on. In this study, a link load balancing method is proposed to address these issues on the data plane, a plane of the software-defined network (SDN) architecture. These problems are NP-complete, so a meta-heuristic approach, discrete particle swarm optimization, is used with a novel hybrid cost function. The superiority of the proposed method over existing methods in the literature is that it provides link and switch load balancing simultaneously. The goal is to choose a path that minimizes the connection load between the source and destination in multipath SDNs. Furthermore, the proposed work is dynamic, so selected paths are regularly updated. Simulation results prove that with the proposed method, streams reach the target with minimum time, no loss, low power consumption, and low memory usage.

• Journal of Information Processing Systems
• /
• v.13 no.2
• /
• pp.236-255
• /
• 2017

The rapid growth of smart devices demands an enhanced throughput for network connection sustainability during mobility. However, traditional wireless network architecture suffers from mobility management issues. In order to resolve the traditional mobility management issues, we propose a novel architecture for future wireless access network based on software-defined network (SDN) by using the advantage of network function virtualization (NFV). In this paper, network selection approach (NSA) has been introduced for mobility management that comprises of acquiring the information of the underlying networking devices through the OpenFlow controller, percepts the current network behavior and later the selection of an appropriate action or network. Furthermore, mobility-related scenarios and use cases to analyze the implementation aspects of the proposed architecture are provided. The simulation results confirm that the proposed scenarios have obtained a seamless mobility with enhanced throughput at minimum packet loss as compared to the existing IEEE 802.11 wireless network.

• Korean Institute of Interior Design Journal
• /
• v.24 no.1
• /
• pp.82-92
• /
• 2015

The philosophers think that the increase of loneliness in technological society is caused by the reduced feeling to some extent. They started to think the integral feeling in terms of existentialism away from Visualcentrism. It is apparent that in architectural design a concrete feeling(sense) out of Visualcentrism of modern architecture is reflected in a architecture. In particular, the architects such as Herzog & de Meuron, Steven Holl, Peter Zumthor, Kuma Kengo think that the existential value of the objects is important and would like to reflect the existence of materials on architecture. This study is to analyze the common points and different points regarding how in these works sensible experiences are approached. The results show that these works have common features containing escape from visual formativeness in the space, pursuit of locational connection, study on pure essence of the materials, and reflectance of the feeling of depth and motility. In addition, the actual beings of the materials for this feeling were mainly used and showed some difference in terms of the usage of local materials, natural environment, five senses of body. This study is important in the point of view that there are few researches that compared with the characteristics of architects' works while there were many researched that treated architecture as sensible view.