• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.2 s.344
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• pp.42-50
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• 2006

Owing to the development of semiconductor processing technology, high density complex circuits can be integrated in a System-on-Chip (SoC). However, increasing energy consumption becomes one of the most important limiting factors. Power estimation at the early stage of design is essential, since design changes at lower levels may significantly lengthen the design period and increase the cost. In this paper, logic level circuits ire levelized and several levels are selected to build power model tables for efficient power estimation. The proposed techniques are applied to a set of ISCAS'85 benchmark circuits to illustrate their effectiveness. Experimental results show that significant improvement in estimation accuracy and slight improvement in efficiency are achieved when compared to those of a well-known existing method. The average estimation error has been reduced from $9.49\%\;to\;3.84\%$.

• Magazine of the Korean Society of Agricultural Engineers
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• v.18 no.1
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• pp.4079-4086
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• 1976

In many reservoir projects, economic considerations will necessitate a design utilizing surcharge. Determination of the most economical combination of surcharge and spillway capacity for a given spillway crest level will require flood routing studies and economic studies of the dam-reservoir-spillway combinations. Many methods of actual flood routing have been devised, each of them with its advantages and disadvantages. Some of these methods are listed below: (1) Arithmetical trial-and-error method. (2) Modified Puls' method (3) Cheng's graphical method (4) Horton's arithmetical method (5) Ekadahl's arithmetical method (6) Digital computer programming. For the purpose of preliminary design and cost estimating of dams and spillways, it is often required to estimate, for a given design flood and spillway crest level. the approximate values of two among the three characteristics of the spillway spillway length, maximum discharge and surcharge depth at maximum discharge, when one of these quantities is given. As is well known, the outflow hydrograph for an ungated overflow spillway assumes the form of a wave-shaped curve with a minimum point for Q=o At zero time and a maximum point for Q=Qmax at its intersection with the falling leg of the inflow hydrograph (see Fig. 4) The shaded area between the inflow and outflow hydrographs represents at the approximate scale the temporary retention Vt. In line with the remarks, draw by free hand the assumed outflow hydrograph with its maximum point for the given Qmax (see Fig. 4) and by planimetration find Vt. From the reservoir capacity curve (Fig. 3) find Vs for the given spillway crest level and make V=Vs+Vt. From the above curve find surcharge water elevation for V and surcharge depth Hmax over spillway crest. From the discharge formula compute {{{{L= { Q} over { { CH}^{3/2 } } }}}} The methed provides a means for a quick and fairly accurate estimation of spillway capacity.

• The Journal of Pediatrics of Korean Medicine
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• v.23 no.1
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• pp.95-113
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• 2009

Objectives This study was investigated to find how the orally administrated Moschus, herbal combination with Moschus, and herbal combination improves the rats' memory and rats' liver. These medications are generally known asthe memory improvement. Methods This study used the Sprague Dawley rats. They were divided into two groups - SD rats and orally administrated Saline(Control group). 0.473 mg/kg Moschus(HM-A), 153.9 mg/kg herbal composition without Moschus(HM-B), and 165.95 mg/kg herbal composition with Moschus combined(HM-C) Control, saline were orally administered. Each group was trained in the eight-arm radial maze task at the conditions of before oral administrated, and also right after third, sixth, and eighth by oral administration. Lastly, these animals were killed and were tested for brain tissue and serum AST/ALT level to measure how the medications were effected to the liver function. Results The result of radial eight-arm maze task test, the HM-B and HM-C groups showed significant decrease in mistakes from the fourth day of testing. Whereas, the HM-A group showed increasing in the error rate. HM-A and HM-C group of rats had significantly increased amount of acetylcholinesterase in the CA1 region of hippocampus, compared to the control group. Whereas, HM-B and HM-C group had increased level of ChAT compared to the control group. On the other hand, each experimental group did not show any significant difference to the level of serum AST/ALT and the weight ratio of the liver to the body. Conclusions This study provided evidences that the orally administered memory improvement herbal medication, and Moschus were effective to improve memory.

• Journal of The Korean Association of Information Education
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• v.5 no.2
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• pp.268-278
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• 2001

This study is design and implementation of diagnosis module using item response theory to assess level of student's knowledge in web-based instruction systems. Item response theory uses responses to items on a test or survey questionnaire to simultaneously locate both the items on the latent trait defined by the set of items while simultaneously scaling each item on the very same dimension. Existing method of measurement in web-based instruction system provided dichromatic learning after to be assess just with the total scores of exam. This measurement has an error that do not consider the level of student's knowledge. Moreover, this method can't perform an exact diagnosis of student knowledge and make student modeling to construct intelligent tutoring system. In this study, we present that design and implement a diagnosis module using item response theory to assess level of student's knowledge in web-based instruction systems

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.6
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• pp.104-110
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• 2008

In this paper, a novel 2-level-search sphere decoding algorithm for multiple-input multiple-output (MIMO) detection and its VLSI implementation are presented. The proposed algorithm extends the search space by concurrently performing symbol detection on 2 level of the tree search. Therefore, the possibility of discarding good candidates can be avoided. Simulation results demonstrate the good performance of the proposed algorithm in terms of bit-error-rate (BER). From the proposed algorithm, an efficient very large scale integration (VLSI) architecture which incorporates low-complexity and fixed throughput features is proposed. The proposed architecture supports many modulation techniques such as BPSK, QPSK, 16-QAM and 64-QAM. The sorting block, which occupies a large portion of hardware utilization, is shared for different operating modes to reduce the area. The proposed hardware implementation results show the improvement in terms of area and BER performance compared with existing architectures.

• Journal of the Korean Society of Radiology
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• v.8 no.7
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• pp.435-441
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• 2014

This paper suggests techniques to enhance coding time which is a problem in traditional fractal compression and to improve fidelity of reconstructed images by determining fractal coefficient through adaptive selection of block approximation formula. First, to reduce coding time, we construct a linear list of domain blocks of which characteristics is given by their luminance and variance and then we control block searching time according to the first permissible threshold value. Next, when employing three-level block partition, if a range block of minimum partition level cannot find a domain block which has a satisfying approximation error, There applied to 24-bpp color image compression and image techniques. The result did not occur a loss in the image quality of the image when using the encoding method, such as almost to the color in the RGB image compression rate and image quality, such as gray-level images and showed good.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.12 no.2
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• pp.275-281
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• 2001

This study examined the relationship between psychopathology(depression, anxiety, aggression), maladaptive cognitions(negative cognitive errors, attributional biases), and age of children with ADHD. 40 ADHD children and their mother completed questionnaires assessing depression, anxiety, aggression level and maladaptive cognitions of children. The results showed that maladaptive cognitions of children with ADHD was not significantly associated with their depression, anxiety, aggression level. Age was negatively related to internal stable attributions for negative events that was characteristic in depression, and had significantly effect on internal stable attributions for negative events. As age of ADHD children increased, their internal attribution for negative events reduced. It seems that their depression and anxiety level is associated with current stress event rather than maladaptive cognitions. Suggestions and limitations of this study, and the directions for future study were discussed.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.5
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• pp.55-61
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• 2007

In this paper, we propose a three-dimensional(3D) active shape models for medical image segmentation. In order to build a 3D shape model, we need to generate a point distribution model(PDM) and select corresponding landmarks in all the training shapes. The manual determination method, two-dimensional(2D) method, and limited 3D method of landmark correspondences are time-consuming, tedious, and error-prone. In this paper, we generate a 3D statistical shape model using the 3D model generation method of a distance transform and a tetrahedron method for landmarking. After generating the 3D model, we extend the shape model training and gray-level model training of 2D active shape models(ASMs) and we use the integrated modeling process with scale and gray-level models for the appearance profile to represent the local structure. Experimental results are comparable to those of region-based, contour-based methods, and 2D ASMs.

• Journal of Korea Multimedia Society
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• v.13 no.3
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• pp.349-358
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• 2010

Adaptability is an important issue in video streaming over mobile environments, since the clients may request videos with great differences in their workload. In this paper, we propose the issues in limited bandwidth scheduling for efficient MPEG-4 video stream transmission over a mobile or wireless network. In the phase of admission control, the amount of bandwidth allocated to serve a video request is the mean bandwidth requirement of its requested video. The dynamic allocation of bandwidth in the phase of scheduling depends on the playback buffer levels of the clients with an objective to make it more adaptive to the playback situation of individual clients. In the proposed RTA scheduling protocol, more bandwidth may be allocated temporarily to the client whose buffer level is low. By employing the buffer level based scheduling policy, this protocol attempts to maximize the real-time performance of individual playback while minimizing the impact of transient overloading. Extensive simulation experiments have been performed to investigate the performance characteristics of the RTA protocol as comparing with BSBA protocol. This RTA protocol shows the better performance by transferring more frames than BSBA protocol.Computer simulations reveals that the standard deviation of the bit rate error of the proposed scheme is 50% less than that of the conventional method.

• Journal of the Korea Institute of Building Construction
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• v.8 no.4
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• pp.105-114
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• 2008

This study investigates the saturation level of surface dryness, quantity of adhesive mortar, and the alien substance content of recycled aggregates for concrete to develop an adequate quality testing method for understanding the properties of recycled aggregates, which differ greatly from preexisting aggregates. For tests that measure the saturation level of surface dryness, where detail methods are applied differently according to the tester, various testing methods from across world were compared and analyzed. This study revealed that when measuring the saturation level of surface dryness of a certain sample, aggregates must be supplemented immediately whenever the height of the sample becomes lower than the measuring mold, and allowing the tamper to free fall on the sample will provide the most accurate results. When measuring the quantity of adhesive mortar of recycled aggregates for concrete, an acid solution was used, and since the quantity of adhesive mortar increases as the particle sizes gets smaller, the sample for testing should represent the entire granularity. Sulfuric acid solution is adequate for immersion, and the concentration should be 20% for best results. According to the alien substance content measurement, which was examined by the naked eye, the error range caused by the difference in particle size was neglectable, and therefore the sample should be $2.5{\sim}5.0mm$ in size concerning the accuracy and measuring time. Also, for coarse recycled aggregates, the sample should amount to 1kg for measuring alien substance content by the naked eye, which proves that assortment by the naked eye is the most adequate method for measuring the alien substance content of a recycled aggregate.