• Title/Summary/Keyword: 3DES

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Effect of 3-Methylcholanthrene on Rat Uterus: Uterine Growth and Mechanism of Action of 3-Methylcholanthrene

  • Sheen, Yhun-Y.;Kim, Sun-S.;Yun, Hea-C.
    • Archives of Pharmacal Research
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    • v.16 no.4
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    • pp.276-282
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    • 1993
  • This study has been undertaken to examine the effect of 3-methylcholanthrene (3MC) on rat uterine growth and to understand the mechanism of action of 3MC in rat uterus. After diethylstilbesterol(DES) or tamoxifen(TAM) or 3MC or DES plus TAM or DES plus 3MC was administered into immature female rats, uterine weight over corn oil-treated uteri. 3MC treatment had no effect on uterine weight but, DES stimulated uterine weight was inhibited by 3MC concomitant tratment. While TAM alone treatment showed slight increase in uterine wieght, inhibited uterine growth simulated by DES when it was adiministrated with DES condirect binding assay with $[^3H]$ estradiol and the relative binding affinities of 3MC and TAM were estimated by competetion assy. Estradiol tumed out to have high affinity for rat uterine estrogen receptor (kd = 0.4 nM). The relative binding affinities of TAM and 3MC were 1% and 4.7% that of DES for rat uterine estrogen receptor, respectively. 3MC was shown to have similar affinity for eat uterine estrogen receptor to that of TAM. Effects of DES 3MC and TAM administration in vivo on rat uterine estrogen recptor level were examined. It was confirmed that the estrogen, DES and antiestrogen, TAM decreased estrogen receptor levels from rat ulterus and also 3MC decreased rat uterine estrogen receptor level when rats were treated with DES, TAM and 3MC in vivo. Data indicates that 3MC acts as an antiestrogen mediated through estrogen receptor system.

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A Study on a Variable P box Generation Using a DES Key Expansion (DES 키 확장을 이용한 가변 P box 생성에 관한 연구)

  • Lee, Jun
    • The KIPS Transactions:PartC
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    • v.18C no.5
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    • pp.287-292
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    • 2011
  • Using an expanded DES key, we suggest a block cipher algorithm to generate and to use a variable P box. We also present an efficient way for the implementation of variable P box at each round. Using counter examples on Differential Cryptanalysis(DC) and Linear Cryptanalysis(LC), we show that the suggested algorithm is strong enough to overcome those attacks. Compared with the real key bits of triple DES(3DES), the new algorithm is much safer in the points of the exhaustive attack. The results of computer simulations show that the new algorithm is almost 3 times faster than 3DES regarding the cipher process time.

Telecommand Decryption Verification for Engineering Qualification Model of Command Telemetry Unit in Communications Satellite (통신위성 원격측정명령처리기 성능검증모델 원격명령 암호복호 검증)

  • Kim, Joong-Pyo;Koo, Cheol-Hea
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.33 no.7
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    • pp.98-105
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    • 2005
  • In this paper, the decryption function of CCSDS telecommand of CTU EQM for the security of communications satellite was verified. In order to intensify the security level of DES CFB decryption algorithm applied to CTU EM, 3DES CFB decryption algorithm using three keys is implemented in the CTU EQM. As the decryption keys increased due to the 3DES algorithm, the keys and IV are stored in PROM memory, and used for the telecommand decryption by taking the keys and IVs corresponding to the selected key and IV indexes from the memory. The operation of the 3DES CFB is validated through the timing simulation of 3DES CFB algorithm, and then the 3DES CFB core implemented on the A54SX32 FPGA. The test environment for the telecommand decryption verification of the CTU EQM was built up. Through sending and decrypting the encrypted command, monitoring the opcodes, and confirming LED on/off by executing the opcodes, the 3DES CFB telecommand decryption function of the CTU EQM is verified.

Dispersion of Aqueous $Al_2O_3$Suspensions with Electrolytes; Influence of the Counter Ion

  • Cecile Pagnoux;Richard Laucournet;Thierry Chartier;Baumard, Jean-Francois
    • The Korean Journal of Ceramics
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    • v.6 no.3
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    • pp.280-285
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    • 2000
  • The electrolyte, $(HO)_2C_6H_2(SO_3Na)_2H_2O $(Tiron), disperses efficiently alumina powder in aqueous media and stable suspensions with 60 vol% solid loading can be prepared. The strong adsorption of this additive is mainly due to the ability of the molecule to form chelate rings with the particle surface but electrostatic interactions between the surface charge and the anionic dispersant strongly influence the amount of Tiron adsorbed. By using a cationic exchange route to substitute the counter ion which neutralizes the sulfonate groups, new molecules of dispersant have been prepared, either with mineral cations as $Li^+,\; Na+^,\; NH_4^\;+$, or with organic cations as counter ion but organic counter ions lead to less to less viscous suspensions than $Na^+$ in particular when the number of carbon atoms of the aliphatic chain increases from 1 to 3.

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A Spread Random Interleaver based Efficient DES Algorithm for Personal Cloud Computing Environments (개인 클라우드 컴퓨팅 환경을 위한 스프레드 랜덤 인터리버 기반의 효율적인 DES 알고리즘)

  • Chung, Yeon Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.1
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    • pp.41-48
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    • 2013
  • An efficient encryption algorithm based on the Data Encryption Standard (DES) for personal cloud computing environments is presented. The proposed algorithm improves data privacy, security and also encryption speed, compared with the triple DES. The improvement of the proposed algorithm stems from enhanced privacy inherent from the use of spread random interleaver in the place of the known substitution table for initial and final permutations in the DES algorithm. The simulation results demonstrate that the interleaver based DES (I-DES) is found to run faster than the triple DES algorithm and also offer improved security. The proposed algorithm also offers encryption for variable-length data using the Cipher Block Chaining (CBC).

Optical Implementation of Triple DES Algorithm Based on Dual XOR Logic Operations

  • Jeon, Seok Hee;Gil, Sang Keun
    • Journal of the Optical Society of Korea
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    • v.17 no.5
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    • pp.362-370
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    • 2013
  • In this paper, we propose a novel optical implementation of a 3DES algorithm based on dual XOR logic operations for a cryptographic system. In the schematic architecture, the optical 3DES system consists of dual XOR logic operations, where XOR logic operation is implemented by using a free-space interconnected optical logic gate method. The main point in the proposed 3DES method is to make a higher secure cryptosystem, which is acquired by encrypting an individual private key separately, and this encrypted private key is used to decrypt the plain text from the cipher text. Schematically, the proposed optical configuration of this cryptosystem can be used for the decryption process as well. The major advantage of this optical method is that vast 2-D data can be processed in parallel very quickly regardless of data size. The proposed scheme can be applied to watermark authentication and can also be applied to the OTP encryption if every different private key is created and used for encryption only once. When a security key has data of $512{\times}256$ pixels in size, our proposed method performs 2,048 DES blocks or 1,024 3DES blocks cipher in this paper. Besides, because the key length is equal to $512{\times}256$ bits, $2^{512{\times}256}$ attempts are required to find the correct key. Numerical simulations show the results to be carried out encryption and decryption successfully with the proposed 3DES algorithm.

On the effect of porosity on the shear correction factors of functionally graded porous beams

  • Ben Abdallah Medjdoubi;Mohammed Sid Ahmed Houari;Mohamed Sadoun;Aicha Bessaim;Ahmed Amine Daikh;Mohamed-Ouejdi Belarbi;Abdelhak Khechai;Aman Garg;Mofareh Hassan Ghazwani
    • Coupled systems mechanics
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    • v.12 no.3
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    • pp.199-220
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    • 2023
  • This article presents a new analytical model to study the effect of porosity on the shear correction factors (SCFs) of functionally graded porous beams (FGPB). For this analysis, uneven and logarithmic-uneven porosity functions are adopted to be distributed through the thickness of the FGP beams. Critical to the application of this theory is a determination of the correction factor, which appears as a coefficient in the expression for the transverse shear stress resultant; to compensate for the assumption that the shear strain is uniform through the depth of the cross-section. Using the energy equivalence principle, a general expression is derived from the static SCFs in FGPB. The resulting expression is consistent with the variationally derived results of Reissner's analysis when the latter are reduced from the two-dimensional case (plate) to the one-dimensional one (beam). A convenient algebraic form of the solution is presented and new study cases are given to illustrate the applicability of the present formulation. Numerical results are presented to illustrate the effect of the porosity distribution on the (SCFs) for various FGPBs. Further, the law of changing the mechanical properties of FG beams without porosity and the SCFare numerically validated by comparison with some available results.

Electrodeposition of SnS Thin film Solar Cells in the Presence of Sodium Citrate

  • Kihal, Rafiaa;Rahal, Hassiba;Affoune, Abed Mohamed;Ghers, Mokhtar
    • Journal of Electrochemical Science and Technology
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    • v.8 no.3
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    • pp.206-214
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    • 2017
  • SnS films have been prepared by electrodeposition technique onto Cu and ITO substrates using acidic solutions containing tin chloride and sodium thiosulfate with sodium citrate as an additive. The effects of sodium citrate on the electrochemical behavior of electrolyte bath containing tin chloride and sodium thiosulfate were investigated by cyclic voltammetry and chronoamperometry techniques. Deposited films were characterized by XRD, FTIR, SEM, optical, photoelectrochemical, and electrical measurements. XRD data showed that deposited SnS with sodium citrate on both substrates were polycrystalline with orthorhombic structures and preferential orientations along (111) directions. However, SnS films with sodium citrate on Cu substrate exhibited a good crystalline structure if compared with that deposited on ITO substrates. FTIR results confirmed the presence of SnS films at peaks 1384 and $560cm^{-1}$. SEM images revealed that SnS with sodium citrate on Cu substrate are well covered with a smooth and uniform surface morphology than deposited on ITO substrate. The direct band gap of the films is about 1.3 eV. p-type semiconductor conduction of SnS was confirmed by photoelectrochemical and Hall Effect measurements. Electrical properties of SnS films showed a low electrical resistivity of $30{\Omega}cm$, carrier concentration of $2.6{\times}10^{15}cm^{-3}$ and mobility of $80cm^2V^{-1}s^{-1}$.

Estrogenicity of 4-nonylphenol and diethylstilbestrol on in vitro oocyte maturation of the dusky tripletooth goby, Tridentiger obscurus

  • Hwang, In-Joon;Kim, Hyun-Woo;Kim, Jin-Koo;Lee, Young-Don;Baek, Hea-Ja
    • Animal cells and systems
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    • v.14 no.3
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    • pp.161-167
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    • 2010
  • This study investigated the estrogenicity of 4-nonylphenol (NP) and diethylstilbestrol (DES) in vitro during oocyte maturation in the marine fish, Tridentiger obscurus, using steroid hormone assays and GVBD assay. Vitellogenic (0.53mm diameter) and fully vitellogenic (0.75mm diameter) oocytes were in vitro exposed to NP (0.045 453.82 nM and DES (0.037 372.62 nM). In vitellogenic oocytes, 45.38 and 453.82nM NP and 3.73 372.62nM DES increas the estradiol-$17{\beta}$ (E2)/testosterone (T) ratio. In fully vitellogenic oocytes, 0.45, 45.38 and 453.82nM NP and 3.73nM DES increased E2/T. In the GVBD assay, 0.45 and 4.54nM NP and 0.037, 3.73 and 37.26nM DES inhibited GVBD. These results suggest that NP and DES have estrogen-agonistic effects in oocyte maturation in T. obscurus. In addition, NP and DES have different sensitivity according to the oocyte developmental stage, and the estrogenagonistic effects of DES were greater than were those of NP.

An Efficient Encryption Technique for Cloud-Computing in Mobile Environments (모바일환경에서 클라우드 컴퓨팅 보안을 위한 효율적인 암호화기술)

  • Hwang, Jae-Young;Choi, Dong-Wook;Chung, Yeon-Ho
    • Journal of the Institute of Convergence Signal Processing
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    • v.12 no.4
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    • pp.298-302
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    • 2011
  • In this paper, we propose an efficient encryption algorithm for ensuring data privacy and security for cloud computing in mobile environments. As part of the evaluation of the proposed algorithm, we have implemented the algorithm in a PC environment and compared with the well-known encryption algorithm of the Data Encryption Standard (DES). The conventional DES algorithm is hard to maintain privacy, due to the fact that its initial and final permutation are known to the network To prevent this critical weakness, a triple DES algorithm has been reported, but it has a disadvantage of long encryption time. In this study, we propose random interleaving algorithm that uses the permutation table for improving privacy further. The proposed algorithm is found to run faster than the triple DES algorithm and also offers improved security in a wireless communication system.