• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.12
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• pp.856-864
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• 2019

The weapon-target assignment (WTA) problem is a matter of effectively allocating weapons to a number of threats. The WTA in a rapidly changing dynamic environment of engagement must take into account both of properties of the threat and the weapon and the effect of the previous decision. We propose a method of applying the Greedy Randomized Adaptive Search Procedure (GRASP) algorithm, a kind of meta-heuristic method, to derive optimal solution for a dynamic WTA problem. Firstly, we define a dynamic WTA problem and formulate a mathematical model for applying the algorithm. For the purpose of the assignment strategy, the objective function is defined and time-varying constraints are considered. The dynamic WTA problem is then solved by applying the GRASP algorithm. The optimal solution characteristics of the formalized dynamic WTA problem are analyzed through the simulation, and the algorithm performance is verified via the Monte-Carlo simulation.

• Journal of Korea Game Society
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• v.17 no.4
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• pp.137-148
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• 2017

Since the power consumption of data centers is large and computer serves take a large portion of it, there have been much research on the power saving of servers in various ways recently. Among the units of severs CPU is one of major power consuming units. In this paper, a method of client-server assignment for minimizing the CPU power consumption of servers in a game server cluster is proposed. We model the client-server assignment problem as an optimization problem, and find a solution to the problem using a simulated annealing-based technique. One of major features of our method is to select a proper operating frequency according to the amount of load on a server. The selection of a lower frequency in case of low load will result in reducing power consumption. To our survey, little research on client-server assignment in consideration of power consumption has been carried out.

• The KIPS Transactions:PartB
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• v.13B no.2 s.105
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• pp.155-162
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• 2006

The medical thesaurus, MeSH (Medical Subject Heading), has been used as a controlled vocabulary thesaurus for English medical paper indexing for a long time. In this paper, we propose an automatic cross language keyword assignment method, which assigns English MeSH index terms to the abstract of a Korean medical paper. We compare the performance with the indexing performance of human indexers and the authors. The procedure of index term assignment is that first extracting Korean MeSH terms from text, changing these terms into the corresponding English MeSH terms, and calculating the importance of the terms to find the highest rank terms as the keywords. For the process, an effective method to solve spacing variants problem is proposed. Experiment showed that the method solved the spacing variant problem and reduced the thesaurus space by about 42%. And the experiment also showed that the performance of automatic keyword assignment is much less than that of human indexers but is as good as that of authors.

• International Journal of Aeronautical and Space Sciences
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• v.12 no.2
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• pp.163-174
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• 2011

Task assignments of multiple unmanned aerial vehicles (UAVs) are examined. The phrase "task assignment" comprises the decision making procedures of a UAV group. In this study, an on-line decentralized task assignment algorithm is proposed for an autonomous UAV group. The proposed method is divided into two stages: an order optimization stage and a communications and negotiation stage. A genetic algorithm and negotiation strategy based on one-to-one communication is adopted for each stage. Through the proposed algorithm, decentralized task assignments can be applied to dynamic environments in which sensing range and communication are limited. The performance of the proposed algorithm is verified by performing numerical simulations.

• Journal of Korean Society of Transportation
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• v.13 no.3
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• pp.19-33
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• 1995

Conventional traffic assignment techniques usually do not consider traveler's route choice behavior affected by hierachicla strucfture in urban highway system. This study realizes the route choice behavior such that travelers tend to choose more higher level of highway rather than lower level of highway for longer trops. Otherwise, for shorter trips, travelers tend to choose lower level of highway unless they can get sufficient travel time saving by using mojor arterial street or freeway (higher level of highway). Therefore, this study suggests a traffic assignment technique incorrporating route choice behavior related to hierachical highway structure by introducing some perception costs to generalized cost function such as perceptional preference measureemnt for higher level higheay and perceptional penalty when changing to different level of highway. Through simulation analysis, it is shown that the simulation results with the new traffic assignment echnique can be different a lot from the results with the convential method.

• Journal of IKEEE
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• v.23 no.4
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• pp.1353-1359
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• 2019

It is presented in this paper that the static output feedback (SOF) pole-assignment problem of some linear time-invariant systems can be completely resolved by parametrization in real Grassmann space. For the real Grassmannian parametrization, the so-called Plucker matrix is utilized as a linear matrix formula formulated from the SOF variable's coefficients of a characteristic polynomial constrained in Grassmann space. It is found that the exact SOF pole assignability is determined by the linear independency of columns of Plucker sub-matrix and by full-rank of that sub-matrix. It is also presented that previous diverse pole-assignment methods and various computation algorithms of the real SOF gains for 2-input, 2-output, 4^th order systems are unified in a deterministic way within this real Grassmannian parametrization method.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.1
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• pp.108-114
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• 1988

We have developed a program that minimizes the chip area with effective code assignment of microinstructions when the control part of VLSI system is implemented in the PLA. While conventional algorithms are composed of one pass, the algorithm proposed in this paper is composed of two passes and it consists of three principal procedures: a procedure for the determination of the code assignment order, a procedure for the code assignment and a procedure for the reduction of the code length. especially, we have proposed a new method of folding back for the reduction of the code length. We have obtained the result of 4 bit code length and 9 product terms when 11 micro-instructions and 6 microoperations were given as a inputs. Therefore, we have certified that it could be used efficiently for the control part of the processors.

• Proceedings of the Korea Contents Association Conference
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• 2005.11a
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• pp.354-358
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• 2005

High-rate WPAN doesn't define the time slot assignment scheduling method of CAT So, there has been many studies regarding time slot assignment scheduling of CAT. However, present studies involve demerits about not applying various types of errors in air interface or having a starvation of a specific DEV. In this paper, we propose algorithms about supplying the intermediate channel assignment in order to avoid these demerits.

• Journal of Power System Engineering
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• v.4 no.4
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• pp.84-91
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• 2000

This paper describes a state feedback controller design method of the integral type magnetic levitation servo system which satisfies the design objectives. The design objective is a $H_{\infty}$ performance, asymptotic disturbance rejection and a robust pole assignment in linear matrix inequality(LMI) region. To the end, we investigated the validity of the designed controller which considering a robust pole assignment region, through results of simulation.

• Journal of the military operations research society of Korea
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• v.23 no.1
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• pp.14-24
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• 1997

This study is to develop an optimal surveillance units assignment model in order to obtain the maximized surveillance efficiency with the limited surveillance units. There are many mathematical models which deal with problems to assign weapons such as aircrafts, missiles and guns to targets. These models minimize the lost required to attack, the threat forecast from the enemy, or both of them. However, a problem of the efficient assignment of surveillance units is not studied yet, nevertbless it is important in the battlefield surveillance system. This paper is concerned with the development of the optimal surveillance units assignment model using integer programming. An optimal integer solution of the model can be obtained by using linear programming and branch and bound method.