• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3B
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• pp.297-306
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• 2008

In order to determine the effects of lock gate expansion at the Lake Youngsan and Yeongam as well as increase in the width of the connecting channel of the two lakes on flood control downstream of the Youngsan River, an unsteady hydraulic flood routing was conducted by combining the Lake Youngsan and Yeongam as a single connected system. The coupled operation of the two lakes was found to have little effect when the widths of the lock gates and the connecting channel are set at the current level. It was also found that increasing the width of the connecting channel as well as the lock gate of the Lake Yeongam is an effective means of reducing the stage of the Lake Youngsan, whereas an increase in the width of the Lake Youngsan's lock gate had a relatively smaller effect. The extended width of the connecting channel leads to a rise in the stage of the Lake Yeongam. In order to reduce the elevated stage, The Lake Yeongam's lock gate must be expanded along with the Lake Yeongsan's lock gate. The analysis found that the stage of the Lake Yeongsan can be effectively controlled through adjustment of opening and shutting criteria of the connecting channel's lock gate, when diversion discharge between the lakes is increased as a result of expanding the width of the connecting channel.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.3B
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• pp.277-284
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• 2010

To examine how the width of connecting channels, the width of the Kumho lock gate, and the opening/shutting criteria of the Yeongam connecting channel lock gate affect the flood stage of Lake Yeongsan, Lake Yeongam, and Lake Kumho, located in the lower reaches of the Yeongsan River, unsteady flood routing was performed by connecting the three lakes into a single interlinked system. The coupled operation of the three lakes was found to have little effect when the widths of the lock gates and the Yeongam and Kumho connecting channels are set at the current level. The most effective way to lower the water level in Lake Yeongsan was to widen the Yeongam connecting channel, but this caused the water level in Lake Yeongam to rise. To lower the increased water level in Lake Yeongam by utilizing the water storage capacity of Lake Kumho, it was necessary to widen both the Kumho lock gate and the Kumho connecting channel. It was found that the optimum opening/shutting criterion for the Yeongam connecting channel lock gate is approximately EL.(+)0.8 m under the simulated conditions used in this study and the criterion allows of maximal lowering of the water levels in Lake Yeongam and Lake Kumho while maintaining a near-constant water level in Lake Yeongsan.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.11
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• pp.804-809
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• 2001

In this paper, a shared channel scheme and routing algorithms are proposed to reduce the number of wavelength channels for the optical WDM multihop networks using the every-other-row-connecting bilayered ShuffleNet scheme. In the shared channel scheme proposed, 2P nodes share the common wavelength channel reducing the number of required channels compare to other ones. By assigning an effective address each node, packets can be routed to the destination nodes through the intermediate nodes.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.7
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• pp.512-519
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• 2009

Flow pulsation in the gap connecting with two parallel channels is investigated by RANS and URANS approaches. The two parallel channels are connected by a small channel called for a gap. The parallel channels are designed to have different cross section area with its ratio of 0.5. Computations are conducted using a CFX 11.0 code. The bulk Reynolds number is 60,000. Predicted results are compared with the previous experimental data. Mean velocity profile at the center of gap region are compared with experiments for its validation. Spectral analysis on the lateral velocity in the center of the gap was performed. Auto correlation for the axial-flow velocity pattern was presented. The unsteady structure of the flow pulsation was visualized in the region of the gap in the parallel channel.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2810-2815
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• 2008

Flow pulsation in the gap connecting with two parallel channels is investigated by RANS and URANS approaches. The two parallel channels are connected by a small channel called for a gap. The parallel channels are designed to have different cross section area with its ratio of 0.5. Computations are conducted using a CFX 11.0 code. The bulk Reynolds number is 60,000. Predicted results are compared with the previous experimental result. Mean velocity profile at the center of gap region are compared with experiments for its validation. Spectral analysis on the lateral velocity in the center of the gap is presented. Auto and cross correlation for the axial-flow velocity pattern are presented. The unsteady structure of the flow pulsation was visualized in the region of the gap in the parallel channel.

• Journal of Korea Water Resources Association
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• v.48 no.12
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• pp.1065-1075
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• 2015

In the estuary where the structure such as river-mouth weir has been installed, the flow is developed very complicatedly due to river water from upstream, tide of the sea and floodgate operation. Especially, if basin outlets more than one exists in one estuary, the boundary conditions will be significantly more complex form. Saemangeum(SMG) project area in Korea is the most typical example. There are Mankyung river and Dongjin river in upstream. The water of them inflows into SMG project area. In the downstream, river flow was drained from inland to sea over the SMG sea dike through the sluice. The connecting channel was located between Mankyung and Dongjin basins. It functions not only as transportation by ship in ordinary period but also as flood sharing by sending flood flow to each other in flood period. Therefore, in order to secure the safety against flood, it is very important to understand the flood sharing capacity for connecting channel. In this study, the flood control effect was analyzed using numerical simulation. Delft3D was used to numerical simulation and simulated period was set up with neap tide, in which the maximum flood stage occurred due to poor drainage. Actually, three connecting channels were designed in land use plan of the SMG Master Plan, but they were simplified to a single channel for conciseness of analysis in this study. According to the results of numerical analysis, the water level difference between two basins was increased and the maximum flood stage at dike sluice was also upraised depending on decrease of conveyance. And the velocity induced by same water level difference was decreased when the conveyance became smaller. In certain conveyance above, there was almost no flood control effect. Therefore, if the results of this study are considered for design of connecting channel, it will be expected to draw the optimal conveyance for minimizing dredging construction cost while maximizing the flood control effect.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.1
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• pp.1-7
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• 1988

A new type broadband channel dropping filter which has a potential use as a millimeter-wave multiplexer has been realized by properly connecting 3-dB directional couplers and bandstop filters. 90\ulcorner3-dB directional couplers have been designed using two nonuniformly coupled dielectric image guides, while bandstop filters with Chebyshev passbands have been designed using dielectric image-guide grating structure. Effective dielectric constant method has been aplied to the image-guide dispersion analysis and to the design of bandstop gratings and 3-dB couplers. Experimental results in excellent agreement with computed responses are demonstrated.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.1
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• pp.50-60
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• 2020

The omni-channel customer system is the communication system between enterprise and customer via multiple channels such as mail, email, SMS, and mobile. The omni-channel customer system complements each other channel through the integration of each channel. The purpose of this research is to derive key factors and calculate the weights that a financial enterprise considers when adopting the omni-channel customer system. For this research, we analyzed the request for proposal documents used for the omni-channel customer system implementation projects in the financial enterprise. Also, we derived, classified, and stratified the key factors to be considered for the introduction of the omni-channel customer system in the financial enterprise. As a result of analyzing the key factors, customer experience, operations, and security were identified as the components of the top category in introducing the omni-channel customer system in the financial sector. Furthermore, the weight for each key factor was calculated by using ANP. As a result of ANP, operations, customer experience, and security were important in order. Also, the degree of easiness for connecting with other systems and the various abilities for representing the contents of the omni-channels were derived as the important key factors.

• Journal of the Korean Society of Costume
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• v.67 no.1
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• pp.40-55
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• 2017

The current new distribution environment provides the consumers to shop at anytime and any places by using mobile appliances. So, the companies which run the offline-store increase the contact point with the consumer by launching not only online-store but also the mobile application (app). Moreover, they are trying to operate the Omni-channel shopping environment. In order for this research to draw the direction of 'the Omni-Channel Strategy', which is about the changed distribution environment of the domestic fashion enterprise, the following steps were performed. First of all, the term related to 'Omni-Channel' is defined. And then, Example of the 'Omni-Channel' strategy and 'O2O' business in the domestic distributior were researched. Lastly, present condition of the 'Omni-Channel' strategy case of the domestic fashion industry was researched. At the result, the online-stores usually have several brands which can not represent their identities. It is suggested that each online-store according to each brand has their own characteristic identity. And The Omni-Channel strategy of the domestic fashion enterprise that is needed the connection point connecting the on-line and off-line. It is able to allure the customer to the off-line-store.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1034-1039
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• 2008

Recently, the sludge suction collector is preferred rather than the scraper type sludge collector due to enhancement of the clarifier efficiency. The sludge suction collector is usually operated by the user's experience without any scientific and technical consideration. There are many factors that should be considered for higher quality of discharged water and stabilized flow in the rectangular sludge suction collector but, the optimal design on the inflow channel and orifices connecting with the inflow channel is needed for similar flow rates at the orifices. The 4 cases of channel geometry are considered and mass flow rates of each case at the orifices are evaluated using Computational Fluid Dynamics applied VOF(Volume of Fraction) model.