• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.19 no.2
• /
• pp.221-227
• /
• 2019

It has long been known that weapon target assignment (WTA) problem is NP-hard. Nonetheless, an exact solution can be found using Brute-Force or branch-and bound method which utilize approximation. Many heuristic algorithms, genetic algorithm particle swarm optimization, etc., have been proposed which provide near-optimal solutions in polynomial time. This paper suggests polynomial time algorithm that can be obtain the optimal solution of WTA problem for the number of total weapons k, the number of weapon types m, and the number of targets n. This algorithm performs k times for O(mn) so the algorithm complexity is O(kmn). The proposed algorithm can be minimize the number of trials than brute-force method and can be obtain the optimal solution.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.17 no.11
• /
• pp.3204-3217
• /
• 2023

In this paper, the downlink of the multicast based spatial modulation systems is investigated. Specifically, physical layer multicasting is introduced to increase the number of access users and to improve the communication rate of the spatial modulation system in which only single radio frequency chain is activated in each transmission. To minimize the bit error rate (BER) of the multicast based spatial modulation system, a joint optimizing algorithm of antenna selection and multicast precoding is proposed. Firstly, the joint optimization is transformed into a mixed-integer non-linear program based on single-stage reformulation. Then, a novel iterative algorithm based on the idea of branch and bound is proposed to obtain the quasioptimal solution. Furthermore, in order to balance the performance and time complexity, a low-complexity deflation algorithm based on the successive convex approximation is proposed which can obtain a sub-optimal solution. Finally, numerical results are showed that the convergence of our proposed iterative algorithm is between 10 and 15 iterations and the signal-to-noise-ratio (SNR) of the iterative algorithm is 1-2dB lower than the exhaustive search based algorithm under the same BER accuracy conditions.

• Smart Structures and Systems
• /
• v.33 no.3
• /
• pp.177-188
• /
• 2024

The fatigue-induced sequential failure of a structure having structural redundancy requires system-level analysis to account for stress redistribution. System reliability-based design optimization (SRBDO) for preventing fatigue-initiated structural failure is numerically costly owing to the inclusion of probabilistic constraints. This study incorporates the Branch-and-Bound method employing system reliability Bounds (termed the B³ method), a failure-path structural system reliability analysis approach, with a metaheuristic optimization algorithm, namely grey wolf optimization (GWO), to obtain the optimal design of structures under fatigue-induced system failure. To further improve the efficiency of this new optimization framework, an additional bounding rule is proposed in the context of SRBDO against fatigue using the B³ method. To demonstrate the proposed method, it is applied to complex problems, a multilayer Daniels system and a three-dimensional tripod jacket structure. The system failure probability of the optimal design is confirmed to be below the target threshold and verified using Monte Carlo simulation. At earlier stages of the optimization, a smaller number of limit-state function evaluation is required, which increases the efficiency. In addition, the proposed method can allocate limited materials throughout the structure optimally so that the optimally-designed structure has a relatively large number of failure paths with similar failure probability.

• Journal of Advanced Navigation Technology
• /
• v.12 no.5
• /
• pp.494-501
• /
• 2008

In this paper, to merge whole 3D information of an occluded body from view point, the new image merging algorithm is introduced after obtaining images of body on the turn table from 4 directions. The two images represented by polygon meshes are merged using weight bipartite matching method with different weights according to coordinates and axes based on minimum distance since two images merged don't present abrupt variation of 3D coordinates and scan direction is one direction. To obtain entire 3D information of body, these steps are repeated 3 times since the obtained images are 4. This proposed method has advantage 200 - 300% searching time reduction rather than conventional branch and bound, dynamic programming, and hungarian method though the matching accuracy rate is a little bit less than these methods.

• Journal of KIISE:Databases
• /
• v.36 no.5
• /
• pp.405-410
• /
• 2009

This paper proposes an efficient path finding scheme capable of searching the paths to k static objects from a given query point, aiming at both improving the legacy k-nearest neighbor search and making it easily applicable to the road network environment. To the end of improving the speed of finding one-to-many paths, the modified A* obviates the duplicated part of node scans involved in the multiple executions of a one-to-one path finding algorithm. Additionally, the cost to the each object found in this step makes it possible to finalize the k objects according to the network distance from the candidate set as well as to order them by the path cost. Experiment results show that the proposed scheme has the accuracy of around 100% and improves the search speed by $1.3{\sim}3.0$ times of k-nearest neighbor searches, compared with INE, post-Dijkstra, and $na{\ddot{i}}ve$ method.

• Journal of Korean Society of Transportation
• /
• v.31 no.2
• /
• pp.80-89
• /
• 2013

The purpose of this research is to optimize the line planning of the intercity passenger railway. In this study, the line planning problem has been formulated into a mixed integer programming by minimizing both user costs (passenger's total travel time) and operator costs (operation, maintenance and vehicle costs) with multiple train types. As a solution algorithm, the branch-and-bound method is used to solve this problem. The change of travel demand, train speed and the number of schedules have been tested through sensitivity analysis. The optimal stop-schedules and frequency as well as system split with respect to each train type have been found in the case study of Kyoung-bu railway line in Korea. The model and results of this research are useful to make a decision for railway operation strategy, to analyze the efficiency of new railway systems and to evaluate the social costs of users and operators.

• Journal of the Korean association of regional geographers
• /
• v.12 no.2
• /
• pp.265-280
• /
• 2006

This study identifies the impact of cultural characteristics on both the behavior of Korean and Japanese tourists, and the corporate strategies of travel agents. The investigation examines travel types(individual or group packaged tour), the travel process, structural change within the travel industry and the behavior of foreign direct investment on tourism-related sectors. The distinctive characteristics of Australia-bound tourism from Japan and Korea were: the high proportion of group packaged tours; strong ethnic linkage in travel activities; the restructuring of travel industry focused on the emergence of large wholesalers; the establishment of overseas branch agents; and the foreign direct investment in resort and hotel properties. The distinctive character of Korean and Japanese travel in Australia was strongly influenced by the collective social group behavior and the strong cultural barriers, notably language and food, of the two countries.

• Journal of Intelligence and Information Systems
• /
• v.12 no.2
• /
• pp.99-123
• /
• 2006

In an effect to composite an optimal supply chain, this study has introduced an agent-based negotiation as a method to assign a lot of orders to a large number of participants. As a resources allocation mechanism to form a strategic cooperation based on information sharing between supply chain members(buyers, manufacturers, suppliers), this agent negotiation provides coordination functions allowing all participants to make a profit and accomplishing Pareto optimum solution from the viewpoint of a whole supply chain. A SET model-based scheduling takes into consideration both earliness production cost and tardiness production cost, along with a competitive relationship between multiple participants. This study has tried to prove that the result of an agent-based negotiation is a Pareto optimal solution under the dynamic supply chain environment, establishing the mathematical formulation for a performance test, and making a comparison with the heuristic Branch & Bound method.

• Journal of the Korea Society of Computer and Information
• /
• v.3 no.4
• /
• pp.174-192
• /
• 1998

These day in the Quality Assurance System, it required that computer system is able to utilize SQC and ISO 9000 series, just then. However. because SQC is necessary to special branch of statistical experience, it is very hard to use and have a bound in that apply to practical business. Therefor in this paper, we proposed the software system which is control, at the same time, SQC and ISO 9000 series, in addition to avail without statistical knowledge. For the shake of this point, the substance of this study is largely separated dual part that ISO 9000 system for which is limited to use design of basic system, test, experiment, tracking incongruent part, analysis condemned goofs, and SQC system for which is to limited to use control chart, estimate, statistical testing, design of experiment(DOE) which used to commonly in Quality Control System. Expected efficiency of this paper is to set Qualify Management System, transfer qualify consciousness, satisfy the customer, increase reliability, in particular, it is expected that it is very useful to minor enterprises of manufacturing-centered.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.12 no.4
• /
• pp.357-363
• /
• 1983

An attempt was made to investigate the lipid contents and fatty acid compositions of the roots (rhizome, epidermis, pith, cortex, branch root, fine root) and aerial parts (seed, flesh of seed, leaf, stem) of ginseng plant. Total contents of free and bound lipids in nine parts ranged 0.91 to 3.48%, those of the seeds were 15.08%. Fourteen even-numbered and 4 odd-numbered fatty acids were identified and quantified by GLC. The major fatty acids in each part were linoleic, palmitic, oleic, and linolenic acid. Fatty acid composition of different parts was varied significantly. Fatty acid composition of ginseng seeds was notably different from those of other parts in plant; the amount of oleic and linoleic acids (51.21 and 37.46%) were higher than those of the other parts. The unsaturated fatty acid content of the free lipid in seed, pith, and cortex were higher than those of the other parts in plant.