• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.24-25
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• 2011

Molecular self-assembly has several advantages over other nanofabrication methods. Molecular building blocks ensure ultrafine pattern precision, parallel structure formation allows for mass production and a variety of three-dimensional structures are available for fabricating complex structures. Nevertheless, the molecular interaction for self-assembly generally relies on weak forces such as van der Waals force, hydrogen bonding, or hydrophobic interaction. Due to the weak interaction, the structure formation is usually slow and the degree of ordering is low in a self-assembled structure. To promote self-assembly, directed assembly methods employing prepatterned substrates or external fields have been developed and gathered a great deal of technological attention as a next generation nanofabrication process. In this presentation a variety of directed assembly methods for soft nanomaterials including block copolymers, peptides and carbon nanomaterials will be introduced. Block copolymers are representative self-assembling materials extensively utilized in nanofabrication. In contrast to colloid assembly or anodized metal oxides, various shapes of nanostructures, including lines or interconnected networks, can be generated with a precise tunability over their shape and size. Applying prepatterned substrates$^{1,2}$ or introducing thickness modulation$^3$ to block copolymer thin films allowed for the control over the orientational and positional orderings of self-assembled structures. The nanofabrication processes for metals, semiconductors$^4$, carbon nanotubes$^{5,6}$, and graphene$^{6,7}$ templating block copolymer self-assembly will be presented.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.5 s.311
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• pp.37-44
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• 2006

In this paper, a new version of the ICM method(MICM, modified ICM) in which the contextual information is modelled by Markov random fields (MRF) is introduced. To extract the feature, a new local MRF model with a fitting block neighbourhood is proposed. This model selects contextual information not only from the relative intensity levels but also from the geometrically directional position of neighbouring cliques. Feature extraction depends on each block's contribution to the local variance. They discriminates it into several regions, for example context and background. Boundaries between these regions are also distinctive. The proposed algerian performs segmentation using directional block fitting procedure which confines merging to spatially adjacent elements and generates a partition such that pixels in unified cluster have a homogeneous intensity level. From experiment with ink rubbed copy images(Takbon, 拓本), this method is determined to be quite effective for feature identification. In particular, the new algorithm preserves the details of the images well without over- and under-smoothing problem occurring in general iterated conditional modes (ICM). And also, it may be noted that this method is applicable to the handwriting recognition.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.2
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• pp.15-21
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• 2008

This paper discuss the sequential digital logic systems and arithmetic operation algorithms which is the important material in computer architecture using analysis and synthesis which is based on extension logic for binary logic over galois fields. In sequential digital logic systems, we construct the moore model without feedback sequential logic systems after we obtain the next state function and output function using building block T-gate. Also, we obtain each algorithms of the addition, subtraction, multiplication, division based on the finite fields mathematical properties. Especially, in case of P=2 over GF($P^m$), the proposed algorithm have a advantage which will be able to apply traditional binary logic directly.The proposed method can construct more efficiency digital logic systems because it can be extended traditional binary logic to extension logic.

• Journal of the Society of Disaster Information
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• v.17 no.2
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• pp.266-274
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• 2021

Purpose: The purpose of this study is to develop a concrete public sign block for floors that can provide pedestrian safety and various information. Method: In order to achieve these research objectives, step-by-step block manufacturing techniques applied in relation to the development of public sign blocks were proposed, and the field applicability of the developed concrete public sign blocks was evaluated. Result: The concrete public sign block for floors developed in this study is expected to be capable of expressing public signs of various shapes and to reduce manufacturing cost. As a result of the usability evaluation for two years, no problems such as cracks, edge dropouts, discoloration, and abrasion were found, so it is judged that sufficient durability was secured. Conclusion: Based on these research results, it is expected that the concrete public sign block will be used as an alternative to secure the weaknesses such as stickers, stone and brass plates that have been used in the existing public sign for floors. It is expected that it can be applied in various fields.

• Journal of Digital Convergence
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• v.18 no.11
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• pp.129-136
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• 2020

The advantages of Blockchain present the necessity of Blockchain in various fields. However, there are several disadvantages to Blockchain. Among them, the uncle block problem is one of the problems that can greatly hinder the value and utilization of Blockchain. Although the value of Blockchain may be degraded by the uncle block problem, previous studies did not pay much attention to research on uncle block. Therefore, the purpose of this study attempts to predict the occurrence of uncle block in order to predict and prepare for the uncle block problem of Blockchain. This study verifies the validity of introducing new attributes and ensemble analysis techniques for accurate prediction of uncle block occurrence. As a research method, voting, bagging, and stacking ensemble analysis techniques were employed for Ethereum's uncle block where the uncle block problem actually occurs. We used Blockchain information of Ethereum and Bitcoin as analysis data. As a result of the study, we found that the best prediction result was presented when voting and stacking ensemble techniques were applied using only Ethereum Blockchain information. The result of this study contributes to more accurately predict the occurrence of uncle block and prepare for the uncle block problem of Blockchain.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.687-692
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• 2018

In this paper, the development of an automotive thermal imaging camera providing image information for ADAS (Advanced Driver Assist System) and autonomous vehicles is described and an improved technique to enhance the details of the image is proposed. Thermal imaging cameras are used in various fields, such as the medical, industrial and military fields, for the purpose of temperature measurement and night vision. In automobiles, they are utilized for night vision systems. For their utilization in ADAS and autonomous vehicles, appropriate image resolution and enhanced detail are required for object recognition. In this study, a $640{\times}480$ resolution thermal imaging camera that can be applied to automobiles is developed and the BDE (Block-Range Detail Enhancement) technique is applied to improve the details of the image. In order to improve the image detail obtained in various driving environments, the block-range values between the target pixel and the surrounding 8 pixels are calculated and classified into 5 levels. Then, different factors are added or subtracted to obtain images with high utilization. The improved technique distinguishes the dark part of the image by the resulting temperature difference of 130mK and shows an improvement in the fine detail in both the bright and dark parts of the image. The developed thermal imaging camera using the improved detail enhancement technique is applied to a test vehicle and the results are presented.

• Radiation Oncology Journal
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• v.20 no.3
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• pp.274-282
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• 2002

Purpose : Measurement of transmission dose is useful for in vivo dosimetry. In this study, the algorithm for estimating the transmission dose for open radiation fields was modified for application to partially blocked radiation fields. Materials and Methods : The beam data was measured with a flat solid phantom with various blocked fields. A new correction algorithm for partially blocked radiation field was developed from the measured data. This algorithm was tested in some settings simulating clinical treatment with an irregular field shape. Results : The correction algorithm for the beam block could accurately reflect the effect of the beam block, with an error within ${\pm}1.0\%$, with both square fields and irregularly shaped fields. Conclusion : This algorithm can accurately estimate the transmission dose in most radiation treatment settings, including irregularly shaped field.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.390-395
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• 2001

Cooling characteristics using convection and conduction heat transfer in a parallel channel with extruding heat sources are studied numerically. A two-dimensional model has been developed for numerical prediction of transient, compressible, viscous, laminar flow, and conjugate heat transfer between parallel plates with uniform block heat sources. The finite volume method is used to solve this problem. The considered assembly consists of two channels formed by two covers and one PCB which has three uniform heat source blocks. Five different cooling methods are considered to find efficient cooling method in a given geometry and heat source. The velocity and temperature fields, local temperature distribution along surface of blocks, and the maximum temperature in each block are obtained.

• Progress in Medical Physics
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• v.5 no.2
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• pp.45-48
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• 1994

We have studied about leaf-width distribution of Multileaf Collimator(MLC). We have analyzed 1169 treatment fields from 303 patients who have treated by radiation therapy. From this analysis, we can design an unevenly leaf-width distributed MLC, by placing the smaller leaf widths for more frequent blocking region and the larger for less. The average width of total leaves is 0.8 cm, but the effective block width is 0.5-0.6 cm for frequently blocking region(3-6 cm from the field center).

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.182-184
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• 2005

An embedded system has been applied to many fields including households and industrial sites. The embedded system is implemented fur image tracking in security area. This system supports a fixed IP far the reliable server operation on TCP/IP networks. A real time video image on the is analyzed to detect a certain invader who jumped into the observed area. The digital camera is connected at the USB host port of the target board. The video images from the video camera is continuously analyzed and displayed at the Linux web-server. The moving vector of the invaders on the continuous image frames is calculated and then it sends the calculated pan/tilt movement. That used Block matching algorithm and edge detection algorithm for past speed. And the displacement vector is used at pan/tilt motor control through RS232 serial cable. The experiment result showed tracking performance by the moving part speed of 10 to 150 pixels/sec.