• Journal of Information Processing Systems
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• v.9 no.2
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• pp.271-286
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• 2013

Recently, a pixel-chaotic-shuffling (PCS) method has been proposed by Huang et al. for encrypting color images using multiple chaotic systems like the Henon, the Lorenz, the Chua, and the Rossler systems. All of which have great encryption performance. The authors claimed that their pixel-chaotic-shuffle (PCS) encryption method has high confidential security. However, the security analysis of the PCS method against the chosen-plaintext attack (CPA) and known-plaintext attack (KPA) performed by Solak et al. successfully breaks the PCS encryption scheme without knowing the secret key. In this paper we present an improved shuffling pattern for the plaintext image bits to make the cryptosystem proposed by Huang et al. resistant to chosen-plaintext attack and known-plaintext attack. The modifications in the existing PCS encryption method are proposed to improve its security performance against the potential attacks described above. The Number of Pixel Change Rate (NPCR), Unified Average Changed Intensity (UACI), information entropy, and correlation coefficient analysis are performed to evaluate the statistical performance of the modified PCS method. The simulation analysis reveals that the modified PCS method has better statistical features and is more resistant to attacks than Huang et al.'s PCS method.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.3
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• pp.95-100
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• 2004

This paper reports a potential problem in the electrical performance of the silicide film to silicon contacts with respect to the scaling trend in integrated circuit (IC) devices. The effects of elastic strain on the agglomeration of the coherent silicide film embedded in an infinite matrix are studied employing continuum linear elasticity and finite-difference numerical method. The interface atomic diffusion is taken to be the dominant transport mechanism where both capillarity and elastic strain are considered for the driving forces. Under plane strain condition with elastically homogeneous and anisotropic system with cubic symmetry, the dilatational misfit and the tetragonal misfit in the direction parallel to the film thickness are considered. The numerical results on the shape evolution agree with the known trend that the equilibrium aspect ratio of the film increases with the elastic strain intensity. When the elastic strain intensity is taken to be only a function of the film size, the flat film morphology with a large aspect ratio becomes increasingly unstable since the equilibrium aspect ratio decreases, as the film scales. The shape evolution results in a large decrease in contact to silicon area, and may deteriorate the electrical performances.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.1
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• pp.14-18
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• 2007

The electric property in the $GaAs-Al_{x}Ga_{1-x}$ quantum well with the Si ${\delta}-doping$ layer in a non-central position is studied through the effect of the electric field intensity on the electron distribution. The finite difference method is used for the calculation of the subband energy level and its wavefunction. In order to account for the change of the potential energy due to the charged particles, the self consistent method is employed. As the Si ${\delta}-doping$ layer becomes closer to the heterojunction interface, the electrons less affected by Coulomb scattering are greatly increased under the external electric field. Therefore, the high speed device is suggested due to the fact that the high mobility electrons can be increased by positioning the ${\delta}-doping$ layer in the quantum well and by applying the electric field intensity.

• Computational Structural Engineering
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• v.6 no.4
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• pp.57-66
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• 1993

The p-version crack model based on integrals of Legendre polynomial and virtual crack extension method is proposed with its potential for application to stress intensity factor computations in linear elastic fracture mechanics. The main advantage of this model is that the data preparation effort is minimal because only a small number of elements are used and high accuracy and the rapid convergence can be achieved in the vicinity of crack tip. There are two important findings from this study. Firstly, the limit value, the strain energy of the exact solution, can be estimated with successive three p-version approximations by ascertaining that the approximations enter the asymptotic range. Secondly, the rate of convergence of p-version model is almost twice that of h-version model on the basis of uniform or quasiuniform mesh refinement for the cracked panel problem subjected to tension.

• Parasites, Hosts and Diseases
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• v.54 no.3
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• pp.357-361
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• 2016

Following the first report of Opisthorchis viverrini infection in a domestic duck in Phu My District of Binh Dinh Province, Central Vietnam, many other cases were observed in the province. We determined the infection rate and intensity of O. viverrini infection in ducks in 4 districts of the province. A total of 178 ducks were randomly selected from 34 farms for examination of flukes in the liver and gall bladder. An infection rate of 34.3% (range 20.7-40.4% among districts) was found; the intensity of infection was 13.8 worms per infected duck (range 1-100). These findings show the role of ducks as a host for O. viverrini, duck genotype, which is sympatric with the human O. viverrini genotype in this province. It also stresses the need for investigations on the zoonotic potential and the life cycle of this parasite.

• Advances in aircraft and spacecraft science
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• v.5 no.6
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• pp.633-652
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• 2018

The present paper focuses on the development of a model for simulating the thermoelectric behavior of CNTs/CFRP Organic Matrix Composite (OMC) laminates for aeronautical applications. The model is developed within the framework of the thermodynamics of irreversible processes and implemented into commercial ABAQUS Finite Element software and validated by comparison with experimental thermoelectric tests on two types of composites materials, namely Type A with Carbon Nanotubes (CNT) and Type B without CNT. A simplified model, neglecting heat conduction, is also developed for simplifying the identification process. The model is then applied for FEM numerical simulation of the thermoelectric response of aircraft panel structures subjected to electrical loads, in order to discuss the potential danger coming from electrical solicitations. The structural simulations are performed on quasi-isotropic stacking sequences (QI) $[45/-45/90/0]_s$ using composite materials of type A and type B and compared with those obtained on plates made of metallic material (aluminum). For both tested cases-transit of electric current of intermediate intensity (9A) and electrical loading on panels made of composite material-higher heating intensity is observed in composites materials with respect to the corresponding metallic ones.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.15-20
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• 2013

Urinary bladder squamous cell carcinoma (SCC), one of the most common neoplasms in Egypt, is attributed to chronic urinary infection with Schistosoma haematobium (Schistosomiasis). The proto-oncogene c-KIT, encoding a tyrosine kinase receptor and implicated in the development of a number of human malignancies, has not been studied so far in schistosomal urinary bladder SCCs. We therefore determined immunohistochemical (IHC) expression of c-KIT in paraffin sections from 120 radical cystectomies of SCCs originally obtained from the Pathology Department of Suez Canal University (Ismailia, Egypt). Each slide was evaluated for staining intensity where the staining extent of >10% of cells was considered positive. c-KIT overexpression was detected in 78.3% (94/120) of the patients, the staining extents in the tumor cells were 11-50% and >50% in 40 (42.6%) and 54 (57.4%) respectively. The positive cases had 14.9%, 63.8%, 21.3% as weak, moderate and strong intensity respectively. Patients with positive bilharzial ova had significantly higher c-KIT expression than patients without (95.2% vs. 38.9%, P=0.000). Mutation analysis of exons 9-13 was negative in thirty KIT positive cases. The high rate of positivity in SBSCC was one of the striking findings; However, CD117 may be a potential target for site specific immunotherapy to improve the outcome of this tumor.

• Journal of the Korean Ceramic Society
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• v.45 no.7
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• pp.380-386
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• 2008

Optimized volume production of nanoscale phosphor powders synthesized by radio frequency (RF) plasma process was developed for the application to plasma display panels. The nano powders were synthesized by feeding the both solid and liquid type precursors, and nanoparticle phosphors were characterized in terms of particle size, shape, and photoluminescence (PL) intensities. Computer simulation was performed in advance to determine the process parameters, and nano phosphors were evaluated by comparing with current commercial micron-sized phosphor powders. Practical feeding of both solid and liquid type precursor was proved to be effective for volume production.The developed process showed a potential as a production method for red, blue and green phosphor although the PL intensity still needs further improvement.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.4
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• pp.261-268
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• 1999

Laser-induced thermochemical etching has been recognized as a new powerful method for processing a variety of materials, including metals, semiconductors, ceramics, insulators and polymers. This study presents characteristics of direct etching for Si substrate using focused argon ion laser beam in aqueous KOH and $CCl_2F_2$ gas. In order to determine process conditions, we first theoretically investigated the temperature characteristics induced by a CW laser beam with a gaussian intensity distribution on a silicon surface. Major process parameters are laser beam power, beam scan speed and reaction material. We have achieved a very high etch rate up to $434.7\mum/sec$ and a high aspect ratio of about 6. Potential applications of this laser beam etching include prototyping of micro-structures of MEMS(micro electro mechanical systems), repair of devices, and isolation of opto-electric devices.

• Atmosphere
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• v.22 no.3
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• pp.331-344
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• 2012

The changes in the Hadley circulation during the second half of the 20th century were examined using observations and the 20C3M (Twentieth Century Climate in Coupled Models) simulations by the 21 IPCC AR4 models. Multi-model ensemble (MME) mean shows that the mean features of the Hadley circulation, such as the intensity, magnitude, and the seasonal variations, are very realistically reproduced, compared to the ERA40 reanalysis. But the long-term trends of the Hadley circulation in 20C3M MME are quite different to those of observations. The observed intensity of the Hadley cell is persistently enhanced, particularly during boreal winter. In comparison, the meridional overturning circulations reproduced in the MME mean remains invariant in time, and even weakened in boreal summer. This discrepancy between the ERA40 and 20C3M MME is consistently shown in the overall structure of the Hadley circulations, such as mass streamfunction, the velocity potential, the vertical shear of meridional wind, and the vertical velocity in the tropical region. This results indicate that the current climate models are skill-less to capture the long-term trend of Hadley circulation yet, and should be improved in simulation of the large-scale features to enhance the confidence level of future climate change projection.