• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.9
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• pp.1167-1176
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• 1995

This paper suggests a method for optimal power assignment of the satellite transponder input carriers in the Multi-level & Multi-bandwidth system. The interference and the noise effects analyzed for the optimal power assignment are intermodulation product caused by the nonlinear transponder characteristics, adjacent channel interference, co-channel interference, and thermal noise in the satellite link. The Fletcher- Powell algorithm is used to determine the optimal input carrier power. The performance criteria for optimal power assignment is classified into 4 categories according to the CNR of destination receiver earth station to meet the requirement for various satellite link environment. We have performed mathematical analysis of objective functions and their derivatives for use in the Fletcher-Powell algorithm, and presented various simulation results based on mathematical analysis. Since the satellite link, it is meaningful to model and analyze these effects in a unified manner and present the method for optimal power assignment of transponder input carriers.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1166-1170
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• 2010

In the case of railway freight, there's a lot of process at railway freight terminal. In these days, for operation efficiency improvement, Load/Unload planning is being carried out research. Load/unload problem can be classified as track assignment, container assignment, yard truck route problem, unload equipment scheduling, container yard plan. In this paper, we focus on track assignment and container assignment among the load/unload problem. we analysis information architecture to solve this problem. And we compares two precesses for existing method and optimization method of track/container assignment processes. An contents different analysis of two methods can shows reformation of an information architecture for load/unload process in the railway freight terminal.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.6
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• pp.2035-2049
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• 2015

Applications deployed in cloud receive a huge volume of requests from geographically distributed users whose satisfaction with the cloud service is directly proportional to the efficiency with which the requests are handled. Assignment of user requests based on appropriate load balancing principles significantly improves the performance of such cloud-based applications. To study the behavior of such systems, there is a need for simulation tools that will help the designer to set a test bed and evaluate the performance of the system by experimenting with different load balancing principles. In this paper, a novel architecture for cloud called Request Assignment Simulator (RAS) is proposed. It is a customizable, visual tool that simulates the request assignment process based on load balancing principles with a set of parameters that impact resource utilization. This simulator will help to ascertain the best possible resource allocation technique by facilitating the designer to apply and test different load balancing principles for a given scenario.

• IE interfaces
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• v.19 no.2
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• pp.160-167
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• 2006

It is a crucial managerial issue how to manage assembly blocks at shipyard. Based on the project experience in Hyundai Heavy Industries, this study points out the difficulties on the block stockyard operations, formalizes the JIBUN (location) assignment problem for assembly blocks, and develops the JIBUN (location) assignment algorithm whose purpose is to reduce the number of unproductive block moves. Through simulation experiments for various situations, this study demonstrates the usefulness of JIBUN (location) assignment algorithm. In addition, this study examines the impacts of block move sequence rules and of block stockyard layouts on the block stockyard operations.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.6
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• pp.176-182
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• 1999

In this paper, we consider a decoupling control and a servo control for the JINAMCHA of which the cart and the pointer is coupled very strongly. The right eigenstructure assignment(i.e. simultaneous assignment of eigenvalues and right eigenvectors) is used for decoupling the motions of the cart and the pointer. The CGT(Command Generator Tracker) is used for a servo control of the JINAMCHA. The performance of the proposed control scheme, that is the combination of the right eigenstructure assignment and the CGT, is evaluated by simulations. The results show that the proposed controller has better performance than the LQR with limiting properties and the conventional LQ servo.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.5
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• pp.2362-2378
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• 2017

To mitigate the performance degradation caused by performance anomaly, a number of channel assignment algorithms have been proposed for multi-rate wireless mesh networks. However, network conditions have not been fully considered for routing process in these algorithms. In this paper, a joint scheme called Multi-rate Dijkstra's Shortest path - Rate Separated (MDSRS) is proposed, combining routing metrics and channel assignment algorithm. In MDSRS, the routing metric are determined through the synthesized deliberations of link costs and rate matches; then the rate separated channel assignment is operated based on the determined routing metric. In this way, the competitions between high and low rate links are avoided, and performance anomaly problem is settled, and the network capacity is efficiently improved. Theoretical analysis and NS-3 simulation results indicate that, the proposed MDSRS can significantly improve the network throughput, and decrease the average end-to-end delay as well as packet loss probability. Performance improvements could be achieved even in the heavy load network conditions.

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.5
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• pp.539-544
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• 2003

The weapon-target assignment problem is solved using a genetic algorithm in this paper. The weapon-target assignment is an optimization problem which minimizes damages from enemy s attack or maximizes the kill probability of targets. Genetic algorithm is applied in this paper since it usually converges to a near global optimal solution. A specific structure of genetic algorithm which is suitable for the weapon-target assignment problem is proposed. A guideline selecting associated parameters is investigated through simulations. Comparition of the proposed method with several traditional optimization techniques for the weapon-target assignment problem shows the validity of the proposed method.

• Journal of the Korea Society of Computer and Information
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• v.18 no.6
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• pp.37-45
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• 2013

In the absence of a single deterministic rule for the channel assignment problems, heuristic algorithms are predominantly employed to partly solve the problems. This paper thus proposes deterministic rules for the channel assignment problems. These deterministic rules have successfully yielded the optimal solution when applied to the Philadelphia's 9 case examples.

• Journal of the Korea Society of Computer and Information
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• v.21 no.1
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• pp.131-138
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• 2016

In this paper, we propose a simple linear bottleneck assignment problems (LBAP) algorithm to find the optimal solution. Generally, the LBAP has been solved by threshold or augmenting path algorithm. The primary characteristic of proposed algorithm is derived the optimal solution of LBAP from linear sum assignment problem (LSAP). Firstly, we obtains the solution for LSAP from the selected minimum cost of rows and moves the duplicated costs in row to unselected row with minimum increasing cost in direct and indirect paths. Then, we obtain the optimal solution of LBAP according to the maximum cost of LSAP can be move to less cost. For the 29 balanced and 7 unbalanced problem, this algorithm finds optimal solution as simple.

• Journal of the military operations research society of Korea
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• v.26 no.1
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• pp.56-69
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• 2000

A frequency assignment problem on time division duplex system is considered. Republic of Korea Army (ROKA) has been establishing an infrastructure of tactical communication (SPIDER) system for next generation and it will be a core network structure of system. VHF system is the backbone network of SPIDER, that performs transmission of data such as voice, text and images. So, it is a significant problem finding the frequency assignment with no interference under very restricted resource environment. With a given arbitrary configuration of communications network, we find a feasible solution that guarantees communication without interference between sites and relay stations. We formulate a frequency assignment problem as an Integer Programming model, which has NP-hard complexity. To find the assignment results within a reasonable time, we take a genetic algorithm approach which represents the solution structure with available frequency order, and develop a genetic operation strategies. Computational result shows that the network configuration of SPIDER can be solved efficiently within a very short time.