• Journal of the Korean Institute of Gas
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• v.7 no.4 s.21
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• pp.24-29
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• 2003

Numerical analysis was conducted to predict the damage of indoor gas explosion for the propagation of explosion flame. Indoor gas diffusion distribution due to gas leakage was obtained by diffusion equation that adopted initial conditions from reference. Enthalpy of each gas-mixture ratio and reduced mechanism was applied to calculate flame temperature, and laminar combustion velocities with the variant of each gas concentration from reference were applied to the gas mixture. Turbulent combustion velocity was modeled by coupling of turbulent energy and laminar combustion velocity in k-$\epsilon$ model. For the analysis of flame propagation cartesian and cylindrical coordinate were used to indoor position and flame propagation respectively. The study analyzes the cause of pressure rising with the variation of flame propagation by glass damage, and the result shows that indoor pressure rising with ignition position varies window dimension.

• International Journal of Computer Science & Network Security
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• v.22 no.11
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• pp.308-318
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• 2022

Noise is a serious issue. While sending images via electronic communication, Impulse noise, which is created by unsteady voltage, is one of the most common noises in digital communication. During the acquisition process, pictures were collected. It is possible to obtain accurate diagnosis images by removing these noises without affecting the edges and tiny features. The New Average High Noise Density Median Filter. (HNDMF) was proposed in this paper, and it operates in two steps for each pixel. Filter can decide whether the test pixels is degraded by SPN. In the first stage, a detector identifies corrupted pixels, in the second stage, an algorithm replaced by noise free processed pixel, the New average suggested Filter produced for this window. The paper examines the performance of Gaussian Filter (GF), Adaptive Median Filter (AMF), and PHDNF. In this paper the comparison of known image denoising is discussed and a new decision based weighted median filter used to remove impulse noise. Using Mean Square Error (MSE), Peak Signal to Noise Ratio (PSNR), and Structure Similarity Index Method (SSIM) metrics, the paper examines the performance of Gaussian Filter (GF), Adaptive Median Filter (AMF), and PHDNF. A detailed simulation process is performed to ensure the betterment of the presented model on the Mini-MIAS dataset. The obtained experimental values stated that the HNDMF model has reached to a better performance with the maximum picture quality. images affected by various amounts of pretend salt and paper noise, as well as speckle noise, are calculated and provided as experimental results. According to quality metrics, the HNDMF Method produces a superior result than the existing filter method. Accurately detect and replace salt and pepper noise pixel values with mean and median value in images. The proposed method is to improve the median filter with a significant change.

• Korean Journal of Veterinary Research
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• v.39 no.4
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• pp.738-742
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• 1999

The objective of this experiment was to investigate the effect of Newcastle disease virus (NDV) and infectious bursal disease virus (IBDV) vaccination on performance of broiler chicks for five weeks. Two types of poultry houses and three patterns of vaccination ($NDV^-/IBDV^-$, $NDV^+/IBDV^-$ and $NDV^+/IBDV^+$) were factorially assigned to six treatments. NDV, B1 strain and IBDV, Bursin-2 vaccine were orally administered at 5, 14 and 7, 18 days, respectively. Forty eight hundred chicks were grouped into four replications with two hundnyd hybro $\times$ hybro chicks per each treatment. Weight gain, feed conversion ratio (FCR), mortality and product index were surveyed at the end of experiment. Bursa index and IBDV antibody titer of chicks were weekly measured. Weight gain of chicks vaccinated with $NDV^+/IBDV^+$ was significantly increased compared to that of other treatments at both window and windowless poultry houses (p<0.05). Chicks vaccinated with $NDV^+/IBDV^+$ also showed significantly improving the FCR and mortality compared to those of other treatments at both poultry houses (p<0.05). The bursa indecies of both poultry houses were high from one-day- to three-weeks-old, but were low for the rest of two weeks. IBDV antibody of all chicks was detected 100% by agar gel precipitation (AGP) test at one day old, but was not detected in $NDV^-/IBDV^-$ and $NDV^+/IBDV^-$ treatments at four weeks old. However, it showed 100% in $NDV^+/IBDV^+$ treatment. Antibody titer using ELISA showed similar trend to that of AGP test. The results of this experiment confirmed that IBDV and NDV combined vaccine significantly improved the performance of broiler chicks.

• Advances in Energy Research
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• v.5 no.3
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• pp.219-226
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• 2017

Electrochemical double layer capacitors (EDLCs) have received a tremendous interest due to their suitability for diverse applications. They have been fabricated using different carbon based electrodes including activated carbons, single walled/multi walled carbon nano tubes. But, graphite which is one of the natural resources in Sri Lanka has not been given a considerable attention towards using for EDLCs though it is a famous carbon material. On the other hand, EDLCs are well reported with various liquid electrolytes which are associated with numerous drawbacks. Gel polymer electrolytes (GPE) are well known alternative for liquid electrolytes. In this paper, it is reported about an EDLC fabricated with a nano composite polyethylene oxide based GPE and two Sri Lankan graphite based electrodes. The composition of the GPE was [{(10PEO: $NaClO_4$) molar ratio}: 75wt.% PC] : 5 wt.% $TiO_2$. GPE was prepared using the solvent casting method. Two graphite electrodes were prepared by mixing 85% graphite and 15% polyvinylidenefluoride (PVdF) in acetone and casting n fluorine doped tin oxide glass plates. GPE film was sandwiched in between the two graphite electrodes. A non faradaic charge discharge mechanism was observed from the Cyclic Voltammetry study. GPE was stable in the potential windows from (-0.8 V-0.8 V) to (-1.5 V-1.5 V). By increasing the width of the potential window, single electrode specific capacity increased. Impedance plots confirmed the capacitive behavior at low frequency region. Galvanostatic charge discharge test yielded an average discharge capacity of $0.60Fg^{-1}$.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.285-285
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• 2011

EUVL (Extreme Ultra Violet Lithography) is one of competitive lithographic technologies for sub-30nm fabrication of nano-scale Si devices that can possibly replace the conventional photolithography used to make today's microcircuits. Among the core EUVL technologies, mask fabrication is of considerable importance since the use of new reflective optics having a completely different configuration compared to those of conventional photolithography. Therefore new materials and new mask fabrication process are required for high performance EUVL mask fabrication. This study investigated the etching properties of SnO2 (Tin Oxide) as a new absorber material for EUVL binary mask. The EUVL mask structure used for etching is SnO2 (absorber layer) / Ru (capping / etch stop layer) / Mo-Si multilayer (reflective layer) / Si (substrate). Since the Ru etch stop layer should not be etched, infinitely high selectivity of SnO2 layer to Ru ESL is required. To obtain infinitely high etch selectivity and very low LER (line edge roughness) values, etch parameters of gas flow ratio, top electrode power, dc self - bias voltage (Vdc), and etch time were varied in inductively coupled Cl2/Ar plasmas. For certain process window, infinitely high etch selectivity of SnO2 to Ru ESL could be obtained by optimizing the process parameters. Etch characteristics were measured by on scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) analyses. Detailed mechanisms for ultra-high etch selectivity will be discussed.

• Analytical Science and Technology
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• v.11 no.4
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• pp.266-270
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• 1998

The Ag-treated activated carbon was prepared by the impregnation of Ag on the home made activated carbon. We investigated the nitrogen adsorption property, surface structure, and antibacterial activity of the carbon. The BET surface areas of Ag impregnated activated carbon are distributed to $740-1112.2m^2/g$ region. The results of nitrogen adsorption property show that BET surface areas move gradually to lower value with increasing $AgNO_3$ mole concentration. From the SEM results, we observed window blocking effect for micropores of external surface of adsorbent by Ag impregnation. Escherichia coli which is a kind of colon bacillus was used as bacteria for antibacterial test. From these results, we also observed that activity increase gradually to larger range with increasing $AgNO_3$ mole ratio.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1370-1372
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• 1998

Boron doped CdS films were prepared by CBD(Chemical Bath Deposition) method using boric acid ($B_3HO_3$) as donor dopant source, and their properties were investigated. As-grown CdS films were highly adherent and specularly reflective. Boron doped CdS film which was fabricated under the condition of 0.01 $B_3HO_3/Cd(Ac)_2$ mole ratio, exhibited the lowest resistivity of $2{\Omega}cm$ and the highest optical bandgap of 2.41eV. Also, CdS/CdTe solar cells were fabricated with various doping concentration of CdS films. Using optimized CdS film as the window layer of CdS/CdTe solar cell, the characteristics of the cell were improved. ( $V_{oc}$=610mV, $J_{sc}$=37.5mA/cm, FF=0.4, $\eta$=9.1% )

• Journal of the Korean Chemical Society
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• v.46 no.6
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• pp.528-534
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• 2002

We have studied to find the optimum electrolyte that satisfied high ionic conductivity, large elec-trochemical window, etc in Li-ion battery. And also studied were the effect of a passive film on carbon anode surface,which is formed by solvent decomposition during the initial charge process. Electrochemical properties of the passive film formed on carbon anode surface investigated and explained as the volumetric ratio of the mixed solvents. The results of scanning electron microscopy, chronopotentiometry, cyclic voltammetry, impedance spectroscopy revealed that the electrochemical properties of the passive film were varied with the ionic conductivity of the electrolyte including the mixed solvents.

• Journal of the Korea Society of Computer and Information
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• v.12 no.1 s.45
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• pp.57-65
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• 2007

In the fast block matching algorithm. search patterns of different shapes or sizes and the distribution of motion vectors have a large impact on both the searching speed and the image qualify. In this paper, we propose a new fast block matching algorithm using the flat-hexagon search pattern that ate solved disadvantages of the diamond pattern search algorithm(DS) and the hexagon-based search algorithm(HEXBS). Our proposed algorithm finds mainly the motion vectors that not close to the center of search window using the flat-hexagon search pattern. Through experiments, compared with the DS and HEXBS, the proposed f)at-hexagon search algorithm(FHS) improves about $0.4{\sim}21.3%$ in terms of average number of search point per motion vector estimation and improves about $0.009{\sim}0.531dB$ in terms of PSNR(Peak Signal to Noise Ratio).

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.2A
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• pp.105-112
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• 2012

Face detection at a distance faces is very challenging since images are often degraded by blurring and noise as well as low resolution. This paper proposes an improved face detection method with AdaBoost filtering and sequential testing stages with color and shape information. The conventional AdaBoost filter detects face regions but often generates false alarms. The face detection method is improved by adopting sequential testing stages in order to remove false alarms. The testing stages comprise skin-color test and variable edge-mask filtering. The skin-color filtering is composed of two steps, which involve rectangular window regions and individual pixels to generate binary face clusters. The size of the variable edge-mask is determined by the ellipse which is estimated from the face cluster. The validation of the horizontal and vertical ratio of the mask is also investigated. In the experiments, the efficacy of the proposed algorithm is proved by images captured by a CCTV and a smart-phone