• Title/Summary/Keyword: Field-enhanced

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A Study of DES(Data Encryption Standard) Property, Diagnosis and How to Apply Enhanced Symmetric Key Encryption Algorithm (DES(Data Encryption Standard) 속성 진단과 강화된 대칭키 암호 알고리즘 적용방법)

  • Noh, Si Choon
    • Convergence Security Journal
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    • v.12 no.4
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    • pp.85-90
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    • 2012
  • DES is a 64-bit binary, and each block is divided into units of time are encrypted through an encryption algorithm. The same key as the symmetric algorithm for encryption and decryption algorithms are used. Conversely, when decryption keys, and some differences may apply. The key length of 64 bits are represented by two ten thousand an d two 56-bit is actually being used as the key remaining 8 bits are used as parity check bits. The 64-bit block and 56-bit encryption key that is based on a total of 16 times 16 modifier and spread through the chaos is completed. DES algorithm was chosen on the strength of the password is questionable because the most widely available commercially, but has been used. In addition to the basic DES algorithm adopted in the future in the field by a considerable period are expected to continue to take advantage of the DES algorithm effectively measures are expected to be in the field note.

Yonsei Evolutionary Population Synthesis for Old Stellar Systems

  • Chung, Chul
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.31.2-31.2
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    • 2012
  • We present the Yonsei Evolutionary Population Synthesis (YEPS) models for spectroscopic and photometric evolutions of simple and composite stellar populations. The models are based on the most up-to-date Yonsei-Yale stellar evolutionary tracks and BaSel 3.1 flux libraries, and provide integrated spectroscopic quantities of Lick/IDS system including high-order Balmer absorption-lines. Special care has been taken to incorporate the systematic variation of horizontal branch (HB) morphology as functions of metallicity, age, alpha-element mixture, and helium abundance of simple stellar populations. Our models for normal-helium stellar populations indicate that the realistic modeling of HB and alpha-element brings about 5 Gyr and 0.1 dex differences in age and metallicity estimations, respectively, compared to those without these effects. The HB effect does not depend on the specific choice of stellar libraries and alpha-element enhancements, and this effect is non-negligible even in the metal sensitive absorption indices, such as Mg2 and Mg b. Comparison of the models to observations reveals that the HB and alpha-element effects are critical in understanding otherwise inexplicable phenomena found in globular cluster systems in the Milky Way and nearby galaxies, including the observed bimodality of the line strengths of globular clusters in massive galaxies. In addition, we found that helium-enhanced stellar populations, which are the major sources of extreme HB stars, bring about increased FUV, NUV fluxes, and thus the model colors of those filters become extremely blue. Age dating based on the YEPS model with normal-helium stellar populations reveals that the evidence for 'downsizing' of elliptical galaxies is found not only in the local field but also in Coma cluster, and that the mean age of elliptical galaxies in Coma cluster is about 1.4 Gyr younger than the mean age of those in the local field. We also find that our models with helium-enhanced subpopulations can naturally reproduce the strong UV-upturns observed in giant elliptical galaxies assuming an age similar to that of old GCs in the Milky Way.

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SiC/SiO2 Interface Characteristics in N-based 4H-SiC MOS Capacitor Fabricated with PECVD and NO Annealing Processes (PECVD와 NO 어닐링 공정을 이용하여 제작한 N-based 4H-SiC MOS Capacitor의 SiC/SiO2 계면 특성)

  • Song, Gwan-Hoon;Kim, Kwang-Soo
    • Journal of IKEEE
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    • v.18 no.4
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    • pp.447-455
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    • 2014
  • In this research, n-based 4H-MOS Capacitor was fabricated with PECVD (plasma enhanced chemical vapor deposition) process for improving SiC/$SiO_2$ interface properties known as main problem of 4H-SiC MOSFET. To overcome the problems of dry oxidation process such as lower growth rate, high interface trap density and low critical electric field of $SiO_2$, PECVD and NO annealing processes are used to MOS Capacitor fabrication. After fabrication, MOS Capacitor's interface properties were measured and evaluated by hi-lo C-V measure, I-V measure and SIMS. As a result of comparing the interface properties with the dry oxidation case, improved interface and oxide properties such as 20% reduced flatband voltage shift, 25% reduced effective oxide charge density, increased oxide breakdown field of 8MV/cm and best effective barrier height of 1.57eV, 69.05% reduced interface trap density in the range of 0.375~0.495eV under the conduction band are observed.

Nutrient Enabled National Agricultural Pesticide Risk Analysis (NAPRA) WWW Decision Support System for Agricultural Best Management Practices (최적관리기법을 위한 웹기반 NAPRA 의사절정 지원시스템)

  • Lim, Kyoung-Jae;Engel Bernard A.;Kim, Ki-Sung;Choi, Joong-Dae
    • Journal of Korean Society of Rural Planning
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    • v.9 no.1 s.18
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    • pp.85-93
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    • 2003
  • Many features of the Single Field version have been enhanced to provide user friendly interface. The County/Watershed version of NAPRA WWW system was further enhanced. The newly developed Web GIS version is an ideal tool for novice users, such as farmers, to simulate the effects of agricultural management for their farms because of its easy-to-use Web GIS interface. The NAPRA WWW system provides an easy to use WWW interface and uses spatial and relational databases to simplify the process of preparing model files. Thus, the NAPRA WWW systems now can be effectively used for nutrient management as well as pesticide management to identify the least impact agricultural management practices.

A Study on the Application of Enhanced Phytoremediation with Plant Growth Promoting Rhizobacteria for Zn Contaminated Rice Paddy Soil (식물성장근권 미생물 적용에 의한 Zn 오염 논토양 식물상정화증진기법 적용에 관한 연구)

  • Kim, Tae-Sung;Choi, Sang-Il;Yang, Jae-Kyu;Lee, In-Sook;Bae, Bum-Han
    • Journal of Soil and Groundwater Environment
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    • v.15 no.3
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    • pp.15-26
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    • 2010
  • The contaminated soils near abandoned mine area can threaten human's health and natural ecosystems through multiple pathways. Remediation of contaminated soil using physicochemical technologies are expensive and destructive of soil environments. On the other hand, environmentally friendly approach that maximize biological remediation, that is, phytoremediation, attracts attention as a low carbon green growth technology. This research is a field demonstration study, focused on the enhanced phytoremediation by bioaugmenting PGPR(Plant Growth Promoting Rhizobacteria)that is helpful on the growth of and heavy metal removal by Echinochloa frumentacea, at a Zn contaminated paddy soil near SamBo mine at Hwasung, Kyunggi. The results showed that the zinc removal by the plant with PSM(Phosphate Solubilizing Bacteria), a kind of PGPR, was three times higher than that by the control. The results are valuable as it is a result from the field-scale technology demonstration. The results also implies that application of PGPR can enhance heavy metal removal from contaminated soil in full scale phytoremediation using Echinochloa frumentacea.

Enhanced nonlinearity of nonlinear optical side-chain polymers (비선형 광 곁가지를 갖는 고분자계의 증대된 비선형 특성)

  • 이종하;이황운;원영희;이석현
    • Korean Journal of Optics and Photonics
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    • v.11 no.1
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    • pp.25-32
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    • 2000
  • Comparisons are made between the first hyperpolarizability $\beta$ of pure N-(4-nitrophenyl)-(L)-prolinol (NPP) and poly (methyl metacrylate) (PMMA) or poly-p-(phenylene terephthalates) (PPT) with NPP side group determined with two different methods, electric-field-induced second-harmonic generation (EFISHG) and hyper-Rayleigh scattering (HRS) methods. Both techniques yield the same values within the experimental errors for pure NPP and NPP-PMMA in 1,1,2,2-tetrachloroethane solution. But the measured results of NPP-PPT polymer in 1,1,2,2-tetrachloroethane solution are showing that the first hyperpolarizability was enhanced with an enhencement of a factor 9.7 in EFISHG and a factor 2.4 in HRS relative to pure NPP. These results indicate that nonlinear optical chromophores organized as side groups of polymers with a rigid backbone contribute coherently to the secondorder nonlinear response of the polymer in the dc electric field as polar polymer chains. hains.

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Relationship between Progressive Changes in Lamina Cribrosa Depth and Deterioration of Visual Field Loss in Glaucomatous Eyes

  • Kim, You Na;Shin, Joong Won;Sung, Kyung Rim
    • Korean Journal of Ophthalmology
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    • v.32 no.6
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    • pp.470-477
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    • 2018
  • Purpose: To investigate the relationship between the progression of visual field (VF) loss and changes in lamina cribrosa depth (LCD) as determined by spectral-domain optical coherence tomography (SD-OCT) enhanced depth imaging in patients with primary open angle glaucoma (POAG). Methods: Data from 60 POAG patients (mean follow-up, $3.5{\pm}0.7$ years) were included in this retrospective study. The LCD was measured in the optic disc image using SD-OCT enhanced depth imaging scanning at each visit. Change in the LCD was considered to either 'increase' or 'decrease' when the differences between baseline and the latest two consecutive follow-up visits were greater than the corresponding reproducibility coefficient value ($23.08{\mu}m$, as determined in a preliminary reproducibility study). All participants were divided into three groups: increased LCD (ILCD), decreased LCD (DLCD), and no LCD change (NLCD). The Early Manifest Glaucoma Trial criteria were used to define VF deterioration. Kaplan-Meier survival analysis and Cox's proportional hazard models were performed to explore the relationship between VF progression and LCD change. Results: Of the 60 eyes examined, 35.0% (21 eyes), 28.3% (17 eyes), and 36.7% (22 eyes) were classified as the ILCD, DLCD, and NLCD groups, respectively. Kaplan-Meier survival analysis showed a greater cumulative probability of VF progression in the ILCD group than in the NLCD (p < 0.001) or DLCD groups (p = 0.018). Increased LCD was identified as the only risk factor for VF progression in the Cox proportional hazard models (hazard ratio, 1.008; 95% confidence interval, 1.000 to 1.015; p = 0.047). Conclusions: Increased LCD was associated with a greater possibility of VF progression. The quantitative measurement of LCD changes, determined by SD-OCT, is a potential biomarker for the prediction of VF deterioration in patients with POAG.

Proposing a multi-mushroom structural system for enhanced seismic performance in large-plan low-rise reinforced concrete buildings

  • Mahmoud Alhashash;Ahed Habib;Mahmood Hosseini
    • Structural Engineering and Mechanics
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    • v.91 no.5
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    • pp.487-502
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    • 2024
  • This study introduces a novel 'multi-mushroom' structural system designed to improve seismic performance in lowrise buildings. Traditional low-rise structures tend to favor sliding over rocking due to their smaller aspect ratios despite the rocking system's superior seismic response reduction. Rocking designs allow structures to pivot at their base during seismic events, reducing damage by dissipating energy. The proposed multi-mushroom system divides the building into four equal sections with small gaps in between, each capable of independent rocking. Numerical analyses are conducted using scaled earthquake records from far- and near-source events to evaluate this system's performance. The results indicated that the multimushroom system significantly reduces plastic hinge formation compared to conventional designs. The system also demonstrated enhanced beam performance and a robust base girder, contributing to reduced collapse vulnerability. The 3-story model exhibited the most favorable behavior, effectively mitigating peak roof drift values, where the rocking system achieved a 21% reduction in mean roof displacement for near-field records and 15% for far-field records. However, the 5-story configuration showed increased roof displacement, and the 7-story model recorded higher incidences of collapse prevention (CP) hinges, indicating areas for further optimization. Overall, the multi-mushroom system enhances seismic resilience by minimizing plastic hinge formation and improving structural integrity. While the system shows significant promise for low-rise buildings, challenges related to roof displacement and inter-story drift ratio in taller structures necessitate further research. These findings suggest that the multi-mushroom system offers a viable solution for seismic risk reduction, contributing to safer and more sustainable urban development in earthquake-prone areas.

The dependence of the electric field effect of diffraction efficiency using polarization beam on calcogenide thin films (칼코게나이드 박막에서 편광 빔 회절 효율의 전계 효과 의존성)

  • Jang, Sun-Joo;Yeo, Cheol-Ho;Park, Jeong-Il;Lee, Hyun-Yong;Chung, Hong-Bay
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1861-1863
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    • 1999
  • The polarization gratings were fabricated in chalcogenide $As_{40}Ge_{10}Se_{15}S_{35}$ thin film applicable to a medium of the polarization holography and their diffraction efficiencies$(\eta)$ were monitored by real-time measurement. The polarization gratings prepared consisted of the multi-layer thin film system. As a method to improve the $\eta$, we have investigated its change for the field effect. As the results, the value of $\eta$ strongly depended on the voltage applied to the film and the maximum value, $\eta_{max}$ was enhanced to be about 4 times in comparison with that of not biased sample. In addition, an increase in the $\eta$ can be estimated to be due to additional creation of new defects caused by the electric field across the film.

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An Accurate and Efficient Method of the Spray Paint Simulation for Robot OLP (로봇 Off-Line Programming을 위한 페인트 스프레이 시뮬레이션 방법론 개발)

  • Lee, Seung-Chan;Song, In-Ho;Borm, Jin-Hwan
    • Korean Journal of Computational Design and Engineering
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    • v.13 no.4
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    • pp.296-304
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    • 2008
  • Recently, various attempts are being done to apply off-line programming system to field of paint robot. But most commercial simulation softwares have problems that are slow simulation speed and not support various painting paramenters on simulation. This paper proposes enhanced paint simulation method for off-line programming system. For these, this method used the mathematical model of flux field from a previous research. The flux field has the flux distribution function, which reflects on the feature of paint spray. A previous research derived this flux distribution function for an integral function and calculated paint thickness function for an integral function. But if flux distribution function is defined as an integral function, it is inadequate to use for real-time simulation because a number of calculation is needed for estimation of paint thickness distribution. Therefore, we defined the flux distribution function by numerical method for reducing a mount of calculation for estimation of paint thickness. We derived the equation of paint thickness function analytically for reducing a mount of calculation from the paint distribution function defined by numerical method. In order to prove proposed paint simulation method this paper compares the simulated and measured thickness. From this comparison this paper show that paint thickness distribution is predicted precisely by proposed spray paint simulation process.