• Journal of the Semiconductor & Display Technology
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• v.5 no.3 s.16
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• pp.37-41
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• 2006

In this paper, a composition modulation of Dot-matrix display grayscale is presented. There's two method of expression of Dot-matrix Display grayscale. One is PWM by controlling pulse width. The other is PAM by controlling pulse amplitude. Composition modulation of Dot-matrix use PWM and PAM together. Composition modulation shows the number of grayscale as number of grayscale of PWM$\times$number of grayscale of PAM and have the effect of reduced size than existing single modulation.

• Journal of the Semiconductor & Display Technology
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• v.17 no.2
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• pp.41-46
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• 2018

This paper proposes a new method for the number recognition on dot matrix LED display. The proposed method uses morphological processing that dilates dots of numbers and connects the dots into strokes. The size of numbers is normalized using horizontal projection because the gaps of dots are different according to the size of numbers. The numbers are segmented by connected component analysis and finally, template matching method recognizes the segmented numbers. The proposed method is implemented using C language in Raspberry Pi system with a camera module for a real-time image processing. Experiments were conducted by using various dot matrix LED displays. The results show that the proposed method is successful for the number recognition on dot matrix LED display.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1255-1257
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• 1998

In this study,$ 5{\times}5$ dot-matrix display was implemented with powder electroluminescent device (PELD). Generally PELD which have a luminance from powder phosphor with electric field, inserted phosphor and dielectric layer between electrodes is basic structure. To make high brightness PELD compared to conventional device, new type of PELD was proposed as follows. New PELD had only one layer, which was mixed phosphor (ZnS:Cu) and dielectric (BaTiO3) material appropriately between electrodes. To compare and estimate the conventional and new type of PELD, the EL spectrum, transferred charge density, brightness and decay time was measured. As above result, we fabricated a hish brightness $ 5{\times}5$ dot-matrix display with new type of PELD. Its brightness was 6400 $cd/m^2$ at 200 V, 400Hz.

• Journal of the Korean Institute of Telematics and Electronics
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• v.14 no.3
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• pp.12-17
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• 1977

Above all computerization of Hangul composite printing is an urgent task for the effective utilization of computer as a useful mean handling information in this information flooded era. However it is a very difficult problems due to the unique mechanism of the Hangul character combination. There in this paper 13$\times$14 Dot Matrix processing method is applied to get a fine result of the Hangul out look. Further more Hangul input/output data processing is accomplished by the software program developed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.3
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• pp.1330-1336
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• 2012

The Image retrieval has been study different approaches which are text-based, contents-based, area-based method and sub-image finding. The sub-image retrieval is to find a query image in the target one. In this paper, we propose a novel sub-image retrieval algorithm by Dot-Matrix method to be used in the bioinformatics. Dot-Matrix is a method to evaluate similarity between two sequences and we redefine the problem for retrieval of sub-image to the finding similarity of two images. For the approach, the 2 dimensional array of image converts a the vector which has gray-scale value. The 2 converted images align by dot-matrix and the result shows candidate sub-images. We used 10 images as target and 5 queries: duplicated, small scaled, and large scaled images included x-axes and y-axes scaled one for experiment.

• The Magazine of the IEIE
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• v.18 no.11
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• pp.1-10
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• 1991

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.5
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• pp.979-984
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• 2009

In this paper, the technique for production and encoding of new dot-type print watermark is proposed. The print watermark has characteristics similar to those of the digital watermark and function as link which change various first informations(texts, symbols, figures, etc) on the printed matter to secondary contents (sound, video, character, etc) corresponding each to informations on the printed matter. The proposed dot-type print watermark pattern is represented as $16{\times}16$ matrix in $0.4mm^2$ area and dots are printed on only 23 elements of $16{\times}16$ matrix. The size of each dot is so small(0.02mm)that it can not be seen. Because position of printed dots correspond to the position of each digit in binary notation in this paper, they are encoded easily and there are about 8,000,000 watermark patterns enough to express first information of printed matters. It was showed that the proposed print watermark patterns are recognized without difficulty by the own recognition device.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.207-207
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• 2012

Si quantum dot (QD) imbedded in a $SiO_2$ matrix is a promising material for the next generation optoelectronic devices, such as solar cells and light emission diodes (LEDs). However, low conductivity of the Si quantum dot layer is a great hindrance for the performance of the Si QD-based optoelectronic devices. The effective doping of the Si QDs by semiconducting elements is one of the most important factors for the improvement of conductivity. High dielectric constant of the matrix material $SiO_2$ is an additional source of the low conductivity. Active doping of B was observed in nanometer silicon layers confined in $SiO_2$ layers by secondary ion mass spectrometry (SIMS) depth profiling analysis and confirmed by Hall effect measurements. The uniformly distributed boron atoms in the B-doped silicon layers of $[SiO_2(8nm)/B-doped\;Si(10nm)]_5$ films turned out to be segregated into the $Si/SiO_2$ interfaces and the Si bulk, forming a distinct bimodal distribution by annealing at high temperature. B atoms in the Si layers were found to preferentially substitute inactive three-fold Si atoms in the grain boundaries and then substitute the four-fold Si atoms to achieve electrically active doping. As a result, active doping of B is initiated at high doping concentrations above $1.1{\times}10^{20}atoms/cm^3$ and high active doping of $3{\times}10^{20}atoms/cm^3$ could be achieved. The active doping in ultra-thin Si layers were implemented to silicon quantum dots (QDs) to realize a Si QD solar cell. A high energy conversion efficiency of 13.4% was realized from a p-type Si QD solar cell with B concentration of $4{\times}1^{20}atoms/cm^3$. We will present the diffusion behaviors of the various dopants in silicon nanostructures and the performance of the Si quantum dot solar cell with the optimized structures.

• Journal of the Chungcheong Mathematical Society
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• v.9 no.1
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• pp.175-181
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• 1996

We show that $\frac{{\partial}x}{{\partial}{\gamma}}(t,{\tau},{\gamma},{\lambda},{\varepsilon})$ is a fundamental matrix of the variational system $\dot{y}=fx(t,x(t,{\tau},{\gamma},{\lambda},{\varepsilon}),{\lambda},{\varepsilon})y$ corresponding to the solution $x(t,{\tau},{\gamma},{\lambda},{\varepsilon})$ of $\dot{x}=f(t,x,{\lambda},{\varepsilon})$.

• Kyungpook Mathematical Journal
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• v.27 no.1
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• pp.55-60
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• 1987

A linear system $\dot{x}= A(t)x$, with A(t+w)=A(t) is considered. A step function approximation of a periodic matrix is constructed. The stability criteria is discussed.