• Structural Engineering and Mechanics
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• v.88 no.1
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• pp.43-52
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• 2023

This paper handles the results of an extensive parametric study on the rotational stiffness of the flexible base connection using ABAQUS program. The results of the parametric study show the relation between the applied moment and the relative rotation for 96 different base connections. The configurations of the studied connections considered different numbers, diameters, and spacing of the anchor bolts along with different thicknesses of the base plate to investigate the effect of these parameters on the rotational stiffness behavior. The results of the previous parametric research used through the whale optimization algorithm (WOA) to detect different equation formulation of the moment-rotation (M-Ɵ_r) equation to detect optimum equation simulates the general nonlinear rotational behavior of the flexible base connection considering all variables used in the parametric study. WOA is a relatively new promising algorithm, which is used in different types of optimization problems. For more verification, the classical genetic algorithm (GA) is used to make a comparison with WOA results. The results show that WOA is capable of getting an optimum equation of the M-Ɵ_r relation, which can be used to simulate the actual rotational stiffness of the flexible base connections. The rotational stiffness at H/150 can be calculated using WOA (1) method and be used as a design aid for engineering design.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.551-556
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• 2004

The Korean Train eXpress(KTX) which started in last April has got many complaints of passengers. This is caused by weak connections between KTX and traditional trains. This paper shows the methods to increase the connection in 3 points of view; business, operation and rolling stocks. For the flexible business, it is necessary that the connecting trains must be multi-purposefully for the satisfaction of KTX transferring passengers and existing commuting passengers. And the expanding of free class is needed. A free class is the base of business flexibility. In an operation point of view, I show the method that can decrease pains for getting transfer. Finally, for the effective using of rolling stocks, I propose that TC(trailer with control) car is added to existing locomotive and passenger coach set. In concluding, KTX needs strong connections with traditional trains. This will bring more competitive power with other transportation systems. And that method must get flexible and various service, in addition to effective and minimizing investment.

• Steel and Composite Structures
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• v.1 no.4
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• pp.459-480
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• 2001

The damage suffered by steel structures during the Northridge (1994) and Kobe (1995) earthquakes indicates that the fully restrained (FR) connections in steel frames did not behave as expected. Consequently, researchers began studying other possibilities, including making the connections more flexible, to reduce the risk of damage from seismic loading. Recent experimental and analytical investigations pointed out that the seismic response of steel frames with partially restrained (PR) connections might be superior to that of similar frames with FR connections since the energy dissipation at PR connections could be significant. This beneficial effect has not yet been fully quantified analytically. Thus, the dissipation of energy at PR connections needs to be considered in analytical evaluations, in addition to the dissipation of energy due to viscous damping and at plastic hinges (if they form). An algorithm is developed and verified by the authors to estimate the nonlinear time-domain dynamic response of steel frames with PR connections. The verified algorithm is then used to quantify the major sources of energy dissipation and their effect on the overall structural response in terms of the maximum base shear and the maximum top displacement. The results indicate that the dissipation of energy at PR connections is comparable to that dissipated by viscous damping and at plastic hinges. In general, the maximum total base shear significantly increases with an increase in the connection stiffness. On the other hand, the maximum top lateral displacement $U_{max}$ does not always increase as the connection stiffness decreases. Energy dissipation is considerably influenced by the stiffness of a connection, defined in terms of the T ratio, i.e., the ratio of the moment the connection would have to carry according to beam line theory (Disque 1964) and the fixed end moment of the girder. A connection with a T ratio of at least 0.9 is considered to be fully restrained. The energy dissipation behavior may be quite different for a frame with FR connections with a T ratio of 1.0 compared to when the T ratio is 0.9. Thus, for nonlinear seismic analysis, a T ratio of at least 0.9 should not be considered to be an FR connection. The study quantitatively confirms the general observations made in experimental results for frames with PR connections. Proper consideration of the PR connection stiffness and other dynamic properties are essential to predict dynamic behavior, no matter how difficult the analysis procedure becomes. Any simplified approach may need to be calibrated using this type of detailed analytical study.

• Journal of Communications and Networks
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• v.13 no.1
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• pp.70-76
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• 2011

This paper presents the unified user equipment (UE) baseband modulation and demodulation (modem) hardware platform architecture to support multiple radio access technologies. In particular, this platform selectively supports two systems; one is HEDGE system, which is the combination of third generation partnership project (3GPP) Release 7 high speed packet access evolution (HSPA+) and global system for mobile communication (GSM)/general packet radio service (GPRS)/enhanced data rates for GSM evolution (EDGE), while the other is LEDGE system, which is the combination of 3GPP Release 8 long term evolution (LTE) and GSM/GPRS/EDGE. This is done by applying the flexible pin multiplexing scheme to a hardwired pin mapping process. On the other hand, to provide stable connection, high portability, and high debugging ability, the stacking structure is employed. Here, a layered board architecture grouped by functional classifications is applied instead of the conventional one flatten board. Based on this proposed configuration, we provide a framework for the verification step in wireless cellular communications. Also, modem function/scenario test and inter-operability test with various base station equipments are verified by system requirements and scenarios.

• Journal of Computational Design and Engineering
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• v.3 no.4
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• pp.363-369
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• 2016

Cyber Physical System (CPS) and Internet of Things (IoT) are hot objects of interest as an extension of the embedded system. These interactive products and systems contain Mobile Devices which are most popular and used most frequently. Also these have been widely used from the control of the Nuclear Power Control System (NPCS) to IoT Home Service. Information & Communication Technology (ICT) topics of trend fused-complex current Information Technology (IT) and Communication Technology (CT) are closely linked to real space and virtual space. This immediately means the arrival of the ultra-connected society. It refers to a society in which various objects surrounding the human innovation and change in the social sector are expected through the connection between the data which are to be generated. In addition, studies of Tool-kit for the design of such systems are also actively pursued. However, only increased cooperation and information sharing between the physical object consists of a variety of machinery and equipment. We have taken into consideration a number of design variables of the high barriers to entry about the product. In this study, It has been developed a Web-based collaboration framework which can be a flexible connection between macroscopically virtual environment and the physical environment. This framework is able to verifiy and manage physical environments. Also it can resolve the bottlenecks encountered during the base expansion and development process of IoT (Internet of Things) environment.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.2
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• pp.50-62
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• 2002

From modernism to post-modernism, the practice in the design field often reduced the complexity of environment and to remove variety. However, contemporary ideas of space have been changed. The current thought premise is that the environment is mutable and is evolving according to inner and outer forces and elements. Therefore, leading designers recognize that the environment is complex in itself while anticipating a new theory explaining on-going trends. The idea of fold formulated by Gilles Deleuze can provide a theoretical base for new environmental design in constrat to current design practices. The fold is a hybrid by accommodating complex relations within an object. It carries a dynamic world view through continual process and yields a topological space against absolute space like Euclid geometry. The characteristics of the fold can be paraphrased as rhizome, stratification and smooth space. Rhizome forms a non-hierarchial connection like networking in internet space. Stratification is a kind of superimposition of autonomous potential layers within a single object. Smooth space is a free space and event oriented space keeping non-linear form. This study tried to incorporate the idea of fold to environmental design methods and design process in order to make space which can correspond with complex environment and topological form. In the design process adapted to fold theory, rhizome analysis accepts the complexity of environment and stratification strategy embraces the possibility of accidental use. As a result, the designed park carries a monadic image and produces an ambiguous space. Lastly, smooth space makes topological space unlike Euclid geometry and is free space comosed by the user themselves. Transporting the idea of fold into environmental design could be an alterative way for indeterminate and flexible design to accept new identity of place. Therefore, this study accepts the concept of incidental morphogenesis to make space based on the complexity of environment. The designed space based on the idea of fold searches to create free event space determined by user rather than designated by designer.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.6
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• pp.36-45
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• 1998

This paper discusses multiple access control aspects for a wireless extension of high-speed asynchronous transfer mode(ATM) networks. One challenging requirement is that mobile systems convey of diverse types of information including voice, computer data, facsimile, and video data that have different quality of service constraints. Basically, a centralized control scheme for a coordinated multiple access is required in order to efficiently accommodate multimedia traffic on wireless links. The proposed scheme dynamically scheduling the mobile terminal, which has data to transfer according to the service, types at base station. In this scheme, the scheduling algorithm is performed on the basis of traffic descriptors and QoS parameters, which required in the connection set up phase. As a consequence, the transmission scheduling is very flexible and can account for the different traffic rate and delay constraints that emerge from voice and data integration. The simulation result shows that the proposed scheme has better performance over other scheduling algorithms.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.417-420
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• 2006

UPnP presents home network middleware for local home electrical appliances basedon internet protocols that is available access and control electrical appliances just in local home network. Itis designed to bring easy-to-use, flexible, standards-based connectivity to ad-hoc or unmanaged networks in the home, a small business, public spaces, or attached to the Internet. In this paper, Internet Gateway expands UPnP IGD(Internet Gateway Device) DCP(Device Control protocol) and UPnP IGP Bridge for Internet Home Network Electrical Appliance Control. UPnP IGD DCP is configurable initiation and sharing of internet connections, advanced connection-management features, management of host configuration service, and supports transparent Internet access by non-UPnP-certified devices. UPnP Bridge search for local home network devices by sending control messages. Control Point of UPnP Bridge search for devices of interest on the network and can control or be controlled all of functions by IGD DCP with control commands. Outside client, approach to UPnP IGD DCP, send control messages UPnP Bridge, and invoke each UPnP device. As a result, Electrical Appliance of Home Network base on UPnP, can control and be controlled via the Internet like ones in the one Home Network without modification of existing UPnP.

• Journal of Korea Port Economic Association
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• v.25 no.3
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• pp.165-182
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• 2009

The purpose of this paper is to study on the third party logistics service enforcement of inland container depot at Pusan area. The main results of this paper are as follows: First, the inland container depot related to location selecting factor researches analyzed and korean TPL market reviewed. Second, the TPL service function reinforcement method and investments are mentioned. In detail the 9 factors are as follows: competitive high position and improvements of harbor back complex, ICD goods enterprise investment strategies, the harbor back which is inexpensive only the rent, taxes benefit and incentive, site security and base facility expansion, the goods service provision which is flexible, connection plan construction of goods enterprise, the incentive strategic establishment which is discriminated, the marketing activity which is long-term. and lastly the ICD and TPL Policy are needed that government and logistic enterprise's cooperation gains competitive advantage.