• Proceedings of the KIEE Conference
• /
• 2003.07a
• /
• pp.381-383
• /
• 2003

The authors have developed a solution method based on the incremental algorithm. The optimal load balance between feeders is found through the incremental algorithm with allowing the loop configuration. Therefore loops can be configured in the resulting configuration, and then we must eliminate all loops to satisfy radiality of distribution system because the distribution system is operated under radial status. But the optimal load balance through incremental algorithm is deteriorated when the loops are eliminated. In this paper, authors propose a new method which is to improve the searching procedure of path in the incremental algorithm, that is, so as not to make loop in the path configuration.

• Journal of the Korean Society for Precision Engineering
• /
• v.20 no.10
• /
• pp.89-97
• /
• 2003

The faults diagnosis of machine tool, which is controlled by CNC(Computer Numerical Control) and PLC(Programmable Logic Controller), is generally based on ladder diagram of PLC because sequential controls for CNC and servo motor are mostly processed in PLC. However, when fault is occurred, a searching of logical relationship for fault reasons is required a lot of diagnosis experiences and times because PLC program has step structure. In this paper, FDS(Fault Diagnosis System) is developed and implemented to machine tool with open architecture controller in order to find the reason of fault fast and correctly. The diagnosed reasons for fault are remote serviced on web through developed RSS(Remote Service System). The operationability and usefulness of developed system are evaluated on specially manufactured machine tool with open architecture CNC. The results of this research can be the model of remote monitoring and fault diagnosis system of machine tool with open architecture CNC.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.58 no.9
• /
• pp.1667-1673
• /
• 2009

This paper presents a application of new algorithm for feeder reconfiguration problem in distribution systems. Harmony Search (HS) algorithm, which is motivated from the musical performance, is used to reconfigure distribution systems so that active power losses are globally minimized with turning on/off the sectionalizing and the tie-line switches. In optimization processing, the HS algorithm has searching ability for the global optimal solution, simple coding of the iteration procedure, and fast convergence to get the solution. The HS algorithm is tested on 15 buses and 69 buses distribution systems, and the results prove its effectiveness to determine appropriate switching options without the occurrence of any misdetermination in switching and get the minimum power loss.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.7 no.4
• /
• pp.223-228
• /
• 2014

It is known that a belief propagation algorithm is a fast decoding scheme for LT codes but it require a large overhead, especially for a short block length LT codes. In this paper an improved belief decoding algorithm using searching method for degree-1 packets is proposed for a small overhead. The proposed decoding scheme shows the desirable performance in terms of overhead while guaranteeing the same computational complexity with respect to the conventional BP decoding scheme.

• The Transactions of the Korea Information Processing Society
• /
• v.4 no.8
• /
• pp.2133-2142
• /
• 1997

Compared with previous compression methods, fractal image compression drastically increases compression rate by using block-based encoding. Although decompression can be done in real time even with softwares, the most serious problem in utilizing the fractal method is the time required for the encoding. In this paper, we propose and verify i) an algorithm that reduces the encoding time by reducing the number of similarity searching on the basis of dimensional informations, and ii) an algorithm that enhances the quality of the restored image on the basis of brightness and contrast information. Finally, a method that enables fast compression with little quality degradation is proposed.

• Journal of information and communication convergence engineering
• /
• v.17 no.3
• /
• pp.191-197
• /
• 2019

Morphological analysis is used for searching sentences and understanding context. As most morpheme analysis methods are based on predefined dictionaries, the problem of a target word not being registered in the given morpheme dictionary, the so-called unregistered word problem, can be a major cause of reduced performance. The current practical solution of such unregistered word problem is to add them by hand-write into the given dictionary. This method is a limitation that restricts the scalability and expandability of dictionaries. In order to overcome this limitation, we propose a novel method to automatically expand a dictionary by means of use-case analysis, which checks the validity of the unregistered word by exploring the use-cases through web crawling. The results show that the proposed method is a feasible one in terms of the accuracy of the validation process, the expandability of the dictionary and, after registration, the fast extraction time of morphemes.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2013.05a
• /
• pp.179-182
• /
• 2013

We develop Framework architecture of Online Shopping Services based on M2M and IoT for Handheld Devices in Cloud Computing. MapReduce model will be used as a method to simplify large scale data processing when user search for purchasing products online which provide efficient, and fast respond time. Therefore, providing user with a enhanced Quality of Experience (QoE) as well as Quality of Service (QoS) when purchasing/searching products Online from big data.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.5
• /
• pp.3378-3384
• /
• 2015

The problem of fast search for raman spectrum has attracted much attention recently. By far the most simple and widely used method is to calculate and compare the Euclidean distance between the given spectrum and the spectra in a database. But it is non-trivial problem because of the inherent high dimensionality of the data. One of the most serious problems is the high computational complexity of searching for the closet codeword. To overcome this problem, The fast codeword search algorithm based on the mean pyramids of codewords is currently used in image coding applications. In this paper, we present three new methods for the fast algorithm to search for the closet codeword. the proposed algorithm uses two significant features of a vector, mean values and variance, to reject many unlikely codewords and save a great deal of computation time. The Experiment results show about 42.8-55.2% performance improvement for the 1DMPS+PDS. The results obtained confirm the effectiveness of the proposed algorithm.

• Journal of Korean Elementary Science Education
• /
• v.29 no.1
• /
• pp.22-31
• /
• 2010

In this study, elementary school teachers' needs for the website providing science instructional materials were examined. The participants were 151 elementary school teachers. The test for needs analysis consisted of fifty-three Likert-type items; 24 items for the content of website category and 29 items for the design of website category. Variables about participants' characteristics such as teaching career, the capability of using computers, and the frequencies of searching websites in obtaining science instructional materials were also examined. The results indicated that teachers' needs for the content of website category were significantly higher than those for the design of website category. Teachers' needs were relatively higher in the items concerning flawless materials, consistency of materials with science curriculum and/or learning objectives, information about target grade and/or related topics, free website, and the materials capable of immediate use in the content of website category. The items concerning the stability of website, the accuracy of links, providing easy and reliable searching methods, easy and fast downloading, and providing list of loaded materials showed relatively higher needs in the design of website category. In several items, teachers' needs were also changed with their individual characteristics.

• Proceedings of the KIEE Conference
• /
• 2007.04a
• /
• pp.26-28
• /
• 2007

The motion estimation is the most important technique in the image compression of the video standards. In the case of next generation standards in the video codec as H.264, a high compression-efficiency can be also obtained by using a motion compensation. To obtain the accurate motion search, a motion estimation should be achieved up to 1/2 pixel and 1/4 pixel uiuts. To do this, the computational complexity is increased although the image compression rate is increased. Therefore, in this paper, we propose the advanced sub-pixel block matching algorithm to reduce the computational complexity by using a statistical characteristics of SAD(Sum of Absolute Difference). Generally, the probability of the minimum SAD values is high when searching point is in the distance 1 from the reference point. Thus, we reduced the searching area and then we can overcome the computational complexity problem. The main concept of proposed algorithm, which based on TSS(Three Step Search) method, first we find three minimum SAD points which is in integer distance unit, and then, in second step, the optimal point is in 1/2 pixel unit either between the most minimum SAD value point and the second minimum SAD point or between the most minimum SAD value point and the third minimum SAD point In third step, after finding the smallest SAD value between two SAD values on 1/2 pixel unit, the final optimized point is between the most minimum SAD value and the result value of the third step, in 1/2 pixel unit i.e., 1/4 pixel unit in totally. The conventional TSS method needs an eight.. search points in the sub-pixel steps in 1/2 pixel unit and also an eight search points in 1/4 pixel, to detect the optimal point. However, in proposed algorithm, only total five search points are needed. In the result. 23 % improvement of processing speed is obtained.