• Journal of the Optical Society of Korea
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• v.20 no.2
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• pp.228-233
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• 2016

In this paper, we propose a nonlinear maximum average correlation height (MACH) filter for information authentication of photon counting double random phase encryption (DRPE). To enhance the security of DRPE, photon counting imaging can be applied because of its sparseness. However, under severely photon-starved conditions, information authentication of DRPE may not be implemented successfully. To visualize the photon counting DRPE, a three-dimensional imaging technique such as integral imaging can be used. In addition, a nonlinear MACH filter can be utilized for helping the information authentication. Therefore, in this paper, we use integral imaging and nonlinear MACH filter to implement the information authentication of photon counting DRPE. To verify our method, we implement optical experiments and computer simulation.

• Proceedings of the KOR-KST Conference
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• 1998.09a
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• pp.91-99
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• 1998

Generally, the tons lifted and ton-kilometers are widely used to analyze the road freight transport. However, these two indicators are simply to show the road freight transport statistics rather than to explain the road freight transportation systems. In this study, the variables such as the number of distribution channel levels, the integral distance, tons in transport and the average transport distance are defined and estimated to investigate the road freight transport system of Korea. In order to compare the road transport system of Korea to other countries, the comparative study was conducted including USA, Japan, Holland and Taiwan. The major findings of this study are as follows; i) The number of distribution channel levels and integral distance of Korea and Taiwan have been increased, but the average transport distance decreased from 1971 to 1996 period. ii) On the contrary to Korea case, the number of distribution channel levels and integral distance of US, Japan and Holland have been decreased, but the average transport distance increased. iii) In the time-series model analysis shows that the number of distribution channel levels are statistically positively closely related to the logistics costs and the costs of transportation as a percentage of GDP.

• Journal of the Korean Society of Safety
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• v.22 no.6
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• pp.46-54
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• 2007

The purpose of this study was to examines the burning rate of fire retardant treated wood in the cone heater with a one-dimensional integral model. The wood samples used in this study were four species. The species of woods are Redwood, White oak, Douglas fir and Maple. Each sample was nominally 50mm thick and 100mm square. Samples were exposed to a range of incident heat fluxes 10 to $35kW/m^2$ using the cone heater. A one-dimension integral model has been used to predict burning rate, heat of gasification, flame heat fluxes, charring rate and char depth of samples. As a result measurement of mass loss rate, softwoods(Redwood and Douglas fir) has relatively low value than those for hardwoods(White oak and Maple). Average charring rate of woods in case of fire retardant treatment showed reduction effect of 41.29%, 50.00%, 48.18% and 60.82% for Redwood, Douglas fir, White fir and Maple, respectively. Almost all the predictions from integral model showed faster charring than those measured. Average difference between predictions and experimental data was 16%, 9.5% and 11.8% for N, F1 and F2 respectively. Water-soluble fire retardant used in this study find out more effect in hardwood than softwood from the result of measurement of mass loss rate and average charring rate.

• Journal of the Optical Society of Korea
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• v.20 no.5
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• pp.579-585
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• 2016

Integral imaging combined with photon-counting detection has been researched for three-dimensional information sensing under low-light-level conditions. This paper addresses the extraction of distance information with photon-counting integral imaging. The longitudinal distance to the object is obtained utilizing photon-counting elemental images. The pixel disparity is estimated by maximizing the nonlinear correlation of photocounts. The first- and second-order statistical properties of the nonlinear correlation are theoretically derived. In the experiments, these properties are verified by varying the mean number of photocounts in the scene. The average distance is compared to that from the intensity information, showing the robustness of the proposed system even at low photocounts.

• Journal of Biosystems Engineering
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• v.42 no.2
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• pp.117-125
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• 2017

Purpose: Damage to pulse crops by wild birds is a serious problem. The damage is to such an extent that the rate of damage during the period between seeding and cotyledon stages reaches 54.6% on an average. In this study, a crop-position detection method was developed wherein infrared (IR) sensors were used to determine the cotyledon position under a vinyl mulch. Methods: IR sensors that helped measure the temperature were used to locate the cotyledons below the vinyl mulch. A single IR sensor module was installed at three locations of the crops (peanut, red lettuce, and crown daisy) in the cotyledon stage. The representative thermal response of a $16{\times}4$ pixel area was detected using this sensor in the case where the distance from the target was 25 cm. A spatial image was applied to the two-dimensional temperature distribution using a non-integral moving-average method. The collected data were first processed by taking the moving average via interpolation to determine the frame where the variance was the lowest for a resolution unit of 1.02 cm. Results: The temperature distribution was plotted corresponding to a distance of 10 cm between the crops. A clear leaf pattern of the crop was visually confirmed. However, the temperature distribution after the normalization was unclear. The image conversion and frequency-conversion graphs were obtained based on the moving average by averaging the points corresponding to a frequency of 40 Hz for 8 pixels. The most optimized resolutions at locations 1, 2, and 3 were found on 3.4, 4.1, and 5.6 Pixels, respectively. Conclusions: In this study, to solve the problem of damage caused by birds to crops in the cotyledon stage after seeding, the vinyl mulch is punched after seeding. The crops in the cotyledon stage could be accurately located using the proposed method. By conducting the experiments using the single IR sensor and a sliding mechanical device with the help of a non-integral interpolation method, the crops in the cotyledon stage could be precisely located.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.1
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• pp.151-165
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• 1996

Relation between condensate retention and heat transfer performance is studied for condensation of CFC-11 on horizontal integral-fin tubes. Eight tubes with trapezoidally shaped integral fin density from 738fpm to 1654fpm and 10, 30 grooves are tested. The liquid retention angles are measured by the height gauge, and each tube is tested under static(non-condensing) condition (CFC-11, water) and under dynamic(condensing) condition (CFC-11). The analytical model predicts the amount of liquid retention on a horizontal integral-fin tubes within＋10 percent over most of the data. Average retention angle increases as both surface tension-to-density ratio($\sigma/\rho$) and fin density(fpm) increase, The tube having a fin density of 1299~1654fpm has the best heat transfer performance. The amount of surface flooding must keep below of 40 percent for best heat transfer performance at condensation. The tube having low number of fin density must be used for fluids having high values of $\sigma/\rho$(water, (TEX)$NH_3$, ect.) and the tube having high number of fin density must be used for the fluid having low values of $\sigma/\rho$(R-11, R-22, etc.)

• Kyungpook Mathematical Journal
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• v.46 no.2
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• pp.219-229
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• 2006

Using the integral average method, we establish some oscillation criteria for the nonlinear differential equation with damped term $$a(t)|{x}^{\prime}(t)|^{\sigma-1}{x}^{\prime}(t)^{\prime}+p(t)|{x}^{\prime}(t)|^{\sigma-1}{x}^{\prime}(t)+q(t)f(x(t))=0,\;{\sigma}>1$$, where the functions $a,\;p$ and $q$ are real-valued continuous functions defined on $[t_o,{\infty})$ with $a(t)>0,\;f(x){\in}C^1(\mathbb{R})$ and $\frac{f^{\prime}(u)}{|f^{({\sigma}-1)/{\sigma}}(u)|}{\geq}k>0$ for $u{\neq}0$.

• Journal of applied mathematics & informatics
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• v.12 no.1_2
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• pp.107-117
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• 2003

We study the integration problem in which one wants to compute the approximation to the definite integral in the average case setting. We choose the composite Newton- Cotes quadratures as our algorithm and the function values at equally spaced sample points on the given interval［0, 1］as information. We compute the average case error of composite Newton-Cotes quadratures and show that it is minimal (modulo a multi-plicative constant).

• Journal of the Korean Society for Railway
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• v.8 no.3
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• pp.222-227
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• 2005

This study investigates the change of the temperature and mechanical properties of the braking disk for the railway vehicle. The average temperature is measured about $100^{\circ}C$ and the maximum temperature is measured over $200^{\circ}C$ by non-contact sensor from Seoul to Chun-an. As a result of measuring, we determine the temperature of test(tensile and J-integral) at $20^{\circ}C,\;100^{\circ}C,\;200^{\circ}C$ and $300^{\circ}C$. In the test, the material values are decreased by the increasing of the temperature. But ratio of decreasing is the largest at $200^{\circ}C$, the tensile test value is decreased about $10\%$ and the J-integral test value is decreased $30\%$. The mechanical properties of this material are mostly changed at $200^{\circ}C$.

• Journal of Korea Game Society
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• v.20 no.3
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• pp.65-74
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• 2020

In the shadow map method, if the shadow map is magnified, the shadow has a jagged silhouette. Herein, we propose a soft shadow method that filters reshaped silhouettes analytically. First, the shadow silhouette is reshaped through sub-texel edge detection, which is based on linear or quadratic curve models. Second, an integral shadow filtering algorithm is used to accurately obtain the average shadow intensity from a definite integral estimation. The implementation demonstrates that our solution can effectively eliminate jagged aliasing and efficiently generate soft shadows.