• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.5
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• pp.787-793
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• 2018

In this paper, we propose a new single carrier - frequency domain equalization (SC-FDE) structure to cope with narrow band interference. In the conventional SC-FDE structure, when a high-power narrow band interference exists, channel estimation and data recovery is difficult. To relieve from this problem, this paper proposes a new SC-FDE frame structure to enable frequency-domain channel estimation in the environments that exist narrow band interference. Specifically, in the conventional method, the channel estimation is performed in time-domain first and from that, the frequency-domain channel is obtained by Fourier transform. In contrast, we proposed a new SC-FDE structure to enable frequency-domain channel estimation directly from received signals without time-domain channel estimation. The receiver performance improvement is verified through computer simulation. According to the results, the proposed technique can detect the signal with less than 2 dB loss compared with jammer-free environments, while the conventional method does not communicate with each other.

• The Transactions of the Korea Information Processing Society
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• v.7 no.2S
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• pp.638-648
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• 2000

This paper introduces a new technique for block is matching motion estimation. Since the temporal correlation of the image sequence, the motion vector of a block is highly related to the motion vector of the same coordinate block in the previous image frame. If we can obtain useful and enough information from the motion vector of the same coordinate block of the previous frame, the total number of search points used to find the motion vector of the current block may be reduced significantly. Using that idea, an efficient predicted direction search algorithm (PDSA) for block matching algorithm is proposed. Based on the direction of the blocks of the two successive previous frames, if the direction of the to successive blocks is same, the first search point of the proposed PDSA is moved two pixels to the direction of the block. The searching process after moving the first search point is processed according to the fixed search patterns. Otherwise, full search is performed with search area $\pm$2. Simulation results show that PSNR values are improved up to the 3.4dB as depend on the image sequences and improved about 1.5dB on an average. Search times are reduced about 20% than the other fast search algorithms. Simulation results also show that the performance of the PDSA scheme gives better subjective picture quality than the other fast search algorithms and is closer to that of the FS(Full Search) algorithm.

• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.3
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• pp.275-284
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• 1999

Unbalanced source voltage in the 3-phase power system is decomposed into positive, negative and zero sequence c components. Also, assuming there is no neutral path in the system, the zero sequence component is not shown on the l load side. Therefore, in the unbalanced power system without neutral path. it is possible to provide balanced voltage to t the load side by compensating negative sequence component and also to regulate the voltage amplitude by controlling t the positive sequence component. In addition, the symmetrical components due to voltage unbalance can be effectively d detected on the synchronous reference frame by using dlongleftarrowq transformation. In this paper, an algorithm not only c compensating unbalanced source voltage by canceling the negative sequence component on the synchronous reference f frame but also maintaining load voltages constantly is proposed. Also a novel method for phase angle detection s synchronized by positive sequence component under unbalanced source voltage is suggested and this detected phase a angle is used for d-q transformation. The performances and characteristics of the proposed compensating system are a analyzed by simulation and verified through experimental results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.1
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• pp.152-164
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• 2015

A rapid development of semiconductors, sensors and mobile network technologies has enable that the embedded device includes high sensitivity sensors, wireless communication modules and a video processing module for vehicular environment, and many researchers have been actively studying the smart car technology combined on the high performance embedded devices. The vehicle is increased as the development of society, and the risk of accidents is increasing gradually. Thus, the advanced driver assistance system providing the vehicular status and the surrounding environment of the vehicle to the driver using various sensor data is actively studied. In this paper, we design and implement the smart vehicular camera device providing the V2X communication and gathering environment information. And we studied the method to create the metadata from a received video data and sensor data using video analysis algorithm. In addition, we invent S-ROI, D-ROI methods that set a region of interest in a video frame to improve calculation performance. We performed the performance evaluation for two ROI methods. As the result, we confirmed the video processing speed that S-ROI is 3.0 times and D-ROI is 4.8 times better than a full frame analysis.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.40 no.1
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• pp.72-78
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• 2003

A new self-organizing neuro-fuzzy network based rate control algorithm for MPEG-4 video encoder is proposed in this paper. Contrary to the traditional methods that construct the rate-distorion (RD) model based on experimental equations, the proposed method effectively exploits the non-stationary property of the video date with neuro-fuzzy network that self-organizes the RD model online and adaptively updates the structure. The method needs not require off-line pre-training; hence it is geared toward real-time coding. The comparative results through the experiments suggest that our proposed rate control scheme encodes the video sequences with less frame skip, providing good temporal quality and higher PSNR, compared to VM18.0.

• Journal of the Korean School Mathematics Society
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• v.12 no.1
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• pp.71-97
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• 2009

The study was to develop the instruments including instructional materials and test items for enhancing spatial ability. A mixed methodology was chosen to achieve the purpose of the study. To find students' achievement, 5 units of instructional materials were developed through the qualitative method and test items were tested through the quantitative method with 152 of the 8th-graders. The strategies to develop the instructional materials were: firstly to focus on mathematics properties for developing spacial ability; secondly, to allow students to follow hierarchical procedure o[ mathematical properties from 2-d to 3-d; thirdly, to recognize what the manipulative can do and can not; and fourthly, to guide students tn develop the process oriented thought, not the result oriented thought. For the test, 25 items were analyzed to assess students' achievement using validity, difficulty, and discriminator.

• Korean Journal of Agricultural Science
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• v.21 no.2
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• pp.103-110
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• 1994

Since the supply of the Southeast Asian tropical timber decreases and its price steeply increases in the international lumber market, door and window frame manufacturers in this country are eagerly searching for their substitutes. This is the first step to replace Southeast Asian tropical timber by low grade North American softwoods, whose reliable and steady supply is expected, but their appearances are not as good as the tropical timber. In this study, knot distribution on the softwood boards and their warp were examined The yield and production cost were also calculated. The average numbers of knots on a door frame were 7.2 for Douglas-fir and 3.4 for Western hemlock. Only 11% of the knots of Douglas-fir door frames are larger than 5cm in diameter, while are 35% of the knots of Western hemlock. The deformations of door frames, after 2 months air-drying, were measured with a warp table. The deformations of Western hemlock door frames were mostly less than 6mm, while those of Douglas-fir distributed in the range of 0.5 and 9.5mm. The yield of Western hemlock is higher than that of Douglas-fir. It can be concluded that the door frames made of the softwoods are compatible with those made of the tropical timber in most aspects except appearance.

• Journal of architectural history
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• v.7 no.4 s.17
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• pp.61-75
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• 1998

The Unite d'Habitation at Marseilles was an experimental project that Le Corbusier had been waiting for since 1920s in order to explore his ideals and visions in mass housing and city planning. As a leader of the first generation members in CIAM, Le Corbusier tried to give a new form and an order to the Unite d'Habitation at Marseilles in both building design and city planning level. The purpose of this research is to investigate the design characteristics of the Unite d'Habitation at Marseilles in three different levels of built environment with a particular emphasis on the process through which an original form is derived from its contextual settings. In the level of city planning, Le Corbusier aimed to reshape traditional low-rise urban housing by deploying several Unites spaciously. Le Corbusier believed that the spacious deployment of Unites would bring us both the functional economy in the city and the natural amenity in the suburbs. As Unite d'Habitation would be called frequently as vertical garden city, the influence of suburban garden city on Unite d'Habitation is apparent. In the building level, the binomial harmony of individual-collectivity was pursued by providing three different public floors and by combining 23 different family unit types in the Unite d'Habitation at Marseilles. In order to visualize the concept of object-type, family units were prefabricated and inserted into the structural frame of the Unite d'Habitation at Marseilles. Two family units are combined to make a three-story section with street corridor in the middle. This three-story section unit is very original as it has access corridor every third floor and each unit could have considerable depth with the help of the living space of two story height. In consideration of formal and plan similarity as well as contextual edivdence, it is concluded that the three-story section of the Unite d'Habitation is derived more from Narkomfin Apartments than from the monastery at Ema or Immuble Villas.

• Korean Journal of Microbiology
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• v.30 no.5
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• pp.403-409
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• 1992

For the development of a glucanolytic yeast strain. the seceretion of endo-1.4-$\beta$-D-glucanase (CMCase) of Bacillus subtilis was performed in yeast using glucoamylase gene (STA1) of Saccharomyces diastaticus. A 1.7 kb-DNA fragment of STA1 gene containing authentic promoter, signal sequence, threonine serine-rich (TS) region and N-terminal region (98 amino acids) of mature glucoamylase was ligated to YEp 24. E. coli-yeast shuttle vector. And then. CMCase structural gene of B. subtilis was fused in frame with the 1.7 kb-DNA fragment of STA1 gene, resulting in recombinant plasmid pYES('24. Yeast transformant harboring pYESC24 had no CMCase activity. So. we deleted TS region and N-terminal region of mature glucoamylase existing between signal sequence and CMCase structural gene in pYESC24. consequently constructed recombinant plasmid pYESC11. The yeast transformed with the newly constructed recombinant plasmid pYESC11 efficiently secreted CMCase to extracellular medium. After 4 days culture. total CMCase activity of this transformant was 44.7 units/ml and over 93% of total CMCase activity was detected in culture supernatant.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.4
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• pp.61-67
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• 2017

Low-dose X-ray fluoroscopic image sequences to avoid radiation exposure risk are contaminated by quantum noise. To restore these noisy sequences, we propose a 3D nonlocal means (NLM) filter based on stochastic distancesed can be applied to the denoising of X-ray fluoroscopic image sequences. The stochastic distance is obtained within motion-compensated noise filtering support to remove the Poisson noise. In this paper, motion-adaptive weight which reflected the frame similarity is proposed to restore the noisy sequences without motion artifact. Experimental results including comparisons with conventional algorithms for real X-ray fluoroscopic image sequences show the proposed algorithm has a good performance in both visual and quantitative criteria.