• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.4
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• pp.80-89
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• 2010

Most of the discussed power efficient routing algorithms, such as LEACH, PEDAP and etc., assume that a base station has infinite resources and there is no traffic limit. However, these assumptions cannot be applied to typical wireless sensor network environments, especially a small sensor network using a normal node as the base station. Moreover, many studies on the wireless sensor networks have not been considering the reverse transmission scheme which transmits data from a sink node to the normal nodes. We propose a bitarray-based reverse routing method which is a power efficient routing algorithm for the wireless sensor networks. The proposed method can be easily implemented by using the tree-based routing scheme and can be worked well with the small memory size for the address of sensor nodes. The experimental result shows that the amount of message transmission of the proposed bitarray-based reverse routing method can be reduced about 61.3% or more compared to the previous methods.

• Industrial Engineering and Management Systems
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• v.12 no.2
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• pp.161-170
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• 2013

Deployment of green transportation in reverse logistics is a key issue for low carbon technologies. To cope with such logistic innovation, this paper proposes a hybrid approach to solve practical vehicle routing problem (VRP) of pickup type that is common when considering the reverse logistics. Noticing that transportation cost depends not only on distance traveled but also on weight loaded, we propose a hierarchical procedure that can design an economically efficient reverse logistics network even when the scale of the problem becomes very large. Since environmental concerns are of growing importance in the reverse logistics field, we need to reveal some prospects that can reduce $CO_2$ emissions from the economically optimized VRP in the same framework. In order to cope with manifold circumstances, the above idea has been deployed by extending the Weber model to the generalized Weber model and to the case with an intermediate destination. Numerical experiments are carried out to validate the effectiveness of the proposed approach and to explore the prospects for future green reverse logistics.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.5
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• pp.1225-1231
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• 2018

FPGA-based system development is being developed as a form of outsourcing that shortens the development time and reduces the cost. Through the process, the risk of letting the hardware Trojan, which causes malfunctions, seep into the system also increases. Various detection methods are proposed for the issue; however, such type of hardware Trojans is inserted by modifying a bitstream directly and therefore, it is hard to detect with the suggested methods. To detect the type of hardware Trojans, it is essential to reverse-engineer the electric circuit implemented by bitstream to a distinguishable level. Specifically, it is important to reverse-engineer the routing information of the circuit that can identify the input-output flow of the signal. In this paper, we analyze the BIL bitstream reverse-engineering tool-chain that uses the algorithm, which retrieves the routing information from FPGA bitstream, and suggest the method to improve the tool-chain.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.9A
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• pp.728-735
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• 2003

It is a mainly issue that provide mobility smoothly in Mobile IP networks. The IP mobility support being standardized in the IETF utilized tunneling of IP packets from a home agent to foreign agent and utilized reverse tunneling of IP packets from foreign agent to home agent. In this paper, We propose that solve the triangular routing problem in IP mobility and that lessen the messages about IETF routing optimization. Through the Mobile Routing Table on the edge router, agent process the message instead of a end node when handoff occur and that lessen the routing path length by sending directly from FA to to Correspond Node's router. This action lessen the message occurrence frequency and the packet drop. We compare the standard IP, Routing Optimization of Mobile IP, Wu's method and the proposed algorithm. Finally, the simulation results are presented.

• Explosives and Blasting
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• v.26 no.2
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• pp.38-44
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• 2008

Recently, planning road construction in South Korea is focused on upgrading of the existing road by rerouting or restructuring. For this, roads under current construction in Korea go for more straight in its alignments and routing. Straight routing makes it all the more required to construct many mountain tunnels and bridges in Korea where mountains are so widely spread. Some portal of mountain tunnel is not rarely planed at high steep slope of mountain valley where it is not easy to secure working space for tunnel excavation. Reverse excavation is an alternative measure for excavation of tunnel portal at high steep slope. Construction in reverse excavation method has three important points requiring careful consideration: 1)planning of pilot tunnel in proper width, height, and length etc., 2)measure against the effect of one-side earth pressure to the direction of tunnel portal, 3)securing tunnel safety against shallow ground condition at portal zone. This paper intends to suggest applicable range of pilot tunnel for reverse excavation at the portal zone located at high steep slope, and shows result of study on the appropriateness of a reverse excavation by means of 3D numerical analysis. Result of 3D numerical analysis for reverse excavation at high steep slope shows that pilot tunneling will be applicable to start from the point $20{\sim}25m$ before the portal from inside the tunnel.

• The KIPS Transactions:PartA
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• v.14A no.2
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• pp.107-116
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• 2007

In this paper, we present a method on the construction of multiple-valued circuits using Reed-Muller Expansions(RME). First, we discussed the input output interconnection of multiple valued function using Perfect Shuffle techniques and Kronecker product and designed the basic cells of performing the transform matrix and the reverse transform matrix of multiple valued RME using addition circuit and multiplication circuit of GF(4). Using these basic cells and the input-output interconnection technique based on Perfect Shuffle and Kronecker product, we implemented the multiple valued logic circuit based on RME. The proposed design method of multiple valued RME is simple and very efficient to reduce addition circuits and multiplication circuits as compared with other methods for same function because of using matrix transform based on modular structures. The proposed design method of multiple valued logic circuits is simple and regular for wire routing and possess the properties of concurrency and modularity of array.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.3
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• pp.613-623
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• 2011

In this paper, we present a method on the construction of quinternary logic circuits using Perfect shuffle. First, we discussed the input-output interconnection of quinternary logic function using Perfect Shuffle techniques and Kronecker product, and designed the basic cells of performing the transform matrix and the reverse transform matrix of quinternary Reed-Muller expansions(QRME) using addition circuit and multiplication circuit of GF(5). Using these basic cells and the input-output interconnection technique based on Perfect Shuffle and Kronecker product, we implemented the quinternary logic circuit based on QRME. The proposed design method of QRME is simple and very efficient to reduce addition circuits and multiplication circuits as compared with other methods for same logic function because of using matrix transform based on modular structures. The proposed design method of quinternary logic circuits is simple and regular for wire routing and possess the properties of concurrency and modularity of array.