• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.529-531
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• 2005

A block-based fast motion estimation algorithm is proposed in this paper to perform motion estimation based on the efficiently reduced search ranges in MPEG-4(ERS). This algorithm divides the search areas into several small search areas and the candidate small search area that has the lowest average of sum norm difference between current macroblock and candidate macroblock is chosen to perform block motion estimation using the Nobel Successive Elimination Algorithm (NSEA). Experimental results of the proposed algorithm show that the averaging PSNR improvement is better maximum 0.125 dB than other tested algorithms and bit saving effect is maximum 20kbps for some tested sequences in low-bit rate circumstance.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1995.06a
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• pp.131-135
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• 1995

As the search range increases, most fast ME algorithms can not keep the performance comparable to the full search BMA. In this paper, we propose a new fast motion estimation method which locates the small search area for a block of the current frame. This method is based on interframe correlation of motion vectors as well as intraframe correlation. Especially, the proposed algorithm outperforms other fast methods when the motion is very fast or complex. It drastically reduces computational complexity while maintaining good performance compared with the conventional FS-BMA.

• Journal of Power Electronics
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• v.15 no.3
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• pp.670-684
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• 2015

The hybrid cascaded multilevel inverter (HCMLI) is a popular converter topology that is being increasingly used in high power medium voltage drives. The intricacy of the control technique for a HCMLI increases with the number of levels and due to fluctuating dc voltages. This paper presents a novel offline quadrant search based space vector modulation technique to synthesize a sinusoidal output from a dispersed pattern of voltage vectors due to different voltages in the auxiliary unit. Such an investigation has never been reported in the literature and it is being attempted for the first time. The method suggested distributes the voltage vectors for a reduced total harmonic distortion at minimal computation. In addition, the proposed algorithm determines the maximum modulation index in the linear modulation range in order to synthesize a sinusoidal output for both normal and abnormal vector patterns. It is better suited for a wide range of practical applications. It is particularly well suited for renewable source fed inverters which utilize large capacitor banks to maintain the dc link, which are prone to such slow fluctuations. The proposed quadrant search space vector modulation technique is simulated using MATLAB/SIMULINK and implemented using a Nexys-2 Spartan-3E FPGA for a developed prototype.

• The Journal of Pediatrics of Korean Medicine
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• v.30 no.2
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• pp.23-30
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• 2016

Objectives The purpose of this study is to investigate recent clinical studies on effect of acupuncture for strabismus in Korea and other countries. We have analyzed 10 years (from 2006 to 2015) of case studies and randomized controlled trials (RCT) on effect of acupuncture for strabismus. Methods The search database includes Oasis, KTKP (Korean Traditional Knowledge Portal), Medline, Embase, and Cochrane library. To narrow the search, the following key search terms were used: 'strabismus, acupuncture'. The search was limited to the publication date from 2006 to 2015. 7 case studies and 5 control studies were selected for analysis. Results and Conclusions 1. The acupuncture treatment is effective for paralytic strabismus 2. The studies used BL1, GB1, ST2, TE23, GB15, EX-HN5, ST1, and LI4 acupoints and also an electroacupuncture treatment, which is 15 minutes of extraocular muscle stimulation, was used. 3. Degree of strasbismus was tested by Ocular motor range test, Corneal light reflex test, Ocular abducent scale test (Scott and Kraft, Diploptic range test).

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.3 s.43
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• pp.271-284
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• 1992

The purpose of this study is to clarify the change of important clothing evaluative criteria according to the clothing buying process and to bulid the flow chart of clothing buying process and clothing evaluative criteria. The study is carried out in two ways, they are, literature study and empirical survey. The results are as following; 1. the change of the important clothing evaluative criteria according to the clothing buying process is found out. 2. The clothing buying process is that problem recognition -1 decision of clothing wearing situation $\rightarrow$ search and evaluation of genaral Clothing information $\rightarrow$ decision of price limit $\rightarrow$ (search and evaluation of brand information 1 narrowing of brand range) $\rightarrow$ search and evaluation of store information $\rightarrow$ decision of store $\rightarrow$ search and evaluation of clothings in the store $\rightarrow$ narrowing of determinant clothing range $\rightarrow$ trial, trial evaluation and decision $\rightarrow$ buy-ing (or reject) $\rightarrow$ result evaluation. 3. The flow chart is built by the clothing buying process and the clothing evaluative criteria

• Journal of Mechanical Science and Technology
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• v.15 no.2
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• pp.217-224
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• 2001

In this paper, the relocation of a mobile robot is considered such that it enables the robot to determine its position with respect to a global reference frame without any $\alpha$ priori position information. The robot acquires sonar range data from a two-dimensional model composed of planes, corners, edges, and cylinders. Considering individual range as data features, the robot searches the best position where the data features of a position matches the environmental model using a constraint-based search method. To increase the search efficiency, a hypothesize and-verify technique is employed in which the position of the robot is calculated from all possible combinations of two range returns that satisfy the sonar sensing model. Accurate relocation is demonstrated with the results from sets of experiments using sparse sonar data in the presence of unmodeled objects.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.5
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• pp.574-580
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• 2013

Compared with the TWS(Track While Scan) tracking that uses scan-to-scan correlation at search illuminations for targets track, a phased array radar can use adaptive tracking which assigns additional track illuminations and the track formation range can be improved as a result. In this paper, an adaptive tracking, the search and track illuminations of a target are synchronized such that the extra illuminations are evenly distributed between the search illuminations, is proposed. Markov chain and track formation range for the proposed adaptive tracking are shown with them for the conventional TWS. The simulation result shows that the proposed adaptive tracking has improved track formation range by 27.6 % compared with the conventional TWS tracking under same track confirmation criterion.

• The Journal of Korea Robotics Society
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• v.4 no.4
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• pp.257-264
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• 2009

This paper proposes a novel face detection method that finds tiny faces located at a long range even with low-resolution input images captured by a mobile robot. The proposed approach can locate extremely small-sized face regions of $12{\times}12$ pixels. We solve a tiny face detection problem by organizing a system that consists of multiple detectors including a mean-shift color tracker, short- and long-rage face detectors, and an omega shape detector. The proposed method adopts the long-range face detector that is well trained enough to detect tiny faces at a long range, and limiting its operation to only within a search region that is automatically determined by the mean-shift color tracker and the omega shape detector. By focusing on limiting the face search region as much as possible, the proposed method can accurately detect tiny faces at a long distance even with a low-resolution image, and decrease false positives sharply. According to the experimental results on realistic databases, the performance of the proposed approach is at a sufficiently practical level for various robot applications such as face recognition of non-cooperative users, human-following, and gesture recognition for long-range interaction.

• Korean Institute of Interior Design Journal
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• v.22 no.5
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• pp.152-161
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• 2013

This study is about the visual appreciation by sex with the analysis of time range of observing data which was got through observation experiment with the space of lobby in hospitals. The observation data of the subjects who observed the space include the frequency and time, through which the process of visual appreciation could be evaluated with the definition of the frequency and the time of observation. First, the fact that men had higher frequency of observation than women means the former had more movement than the latter, and another fact of their fewer times can be understood as the time of their staying was shorter. That is, even though the men had more movements of sight, they showed the feature of staying shorter. Second, the rate high and low of observation frequency and times made it possible for observation characteristics to be defined as 'intensive search' 'active search' 'fixed concentration' and 'search wandering.' The definition of understanding this process of visual appreciation can be available for a frame of effective analysis of observation characteristics according to the passage of time. Third, the intense search is the case of 'high frequency' having the feature of high visual appreciation owing to the active visual actions for acquiring information. Men were found to have more intense search which decreased gradually as time passed, while women showed the feature of many times of intense search. Fourth, it was found that with many observation data in a certain range of time the subjects had fixed concentration, where women were found to have repetitive fixed concentration along with the change of observation time while men were seen to have more observation tendency for fixed concentration. Fifth, at the cross tabulation of frequency and times, men had the feature of dispersed visual appreciation while women had more distinction between fixation and movement, which revealed that there is surely the difference between men and women in the process of visual appreciation.

• Korean Management Science Review
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• v.32 no.4
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• pp.81-96
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• 2015

This paper models knowledge diffusion on an inter-organizational network. Based on literatures related to knowledge diffusion, the model considers critical factors that affect diffusion behavior including nodal property, relational property, and environmental property. We examine the relationships among network structure, knowledge search, and diffusion performance. Through a massive simulation runs based on the agent-based model, we find that the average path length of a network decreases a firm's cumulative knowledge stock, whereas the clustering coefficient of a firm has no significant relationship with the firm's knowledge. We also find that there is an interaction effect of network structure and the range of knowledge search on knowledge diffusion. Specifically, in a network of a larger average path length (APL) the marginal effect of search conduct is significantly greater than in that of a smaller APL.