Asymmetric

Graph Theory is one of the significant and important areas in Mathematics, which is used in Network Security. Cryptography is art of science to achieving security by encoding message to make it non-readable (secretive) to unintended users. Many techniques are presents to encrypt plain text and convert it to the cipher text [2]. Any cryptographic scheme is secure if and only if it is unbreakable in reasonable time, using feasible resources in spite of the intruder's being aware of the encryption and decryption algorithm and size of the key. In the proposed algorithm, adjacent matrix of graph can be used to obtain key for encryption and decryption which is safer compared to other keys.

Abstract: Encryption is the most effective way to achieve data security. It is the process in which plain text converts into a cipher text and allows only authorized people to access the sender information. In this research paper I would like to explain different types of encryption techniques such as hashing function and symmetric and asymmetric methods with advantages and disadvantages including necessary practical examples.
Keywords: Encryption, Cryptography, Hashing, Asymmetric, Symmetric, Cipher text
Title: Encryption
Author: Sruthi Medasani, Professor Tarik El Taeib,
International Journal of Computer Science and Information Technology Research
ISSN 2348-1196 (print), ISSN 2348-120X (online)
Research Publish Journals

New version of Novikov helical gear combining double circular arc profile with crowned involute profile has been proposed in this paper. Generation of this gear is carried out using the required equations for these two profiles which are programmed using SOLIDWORK. To compare the resulting contact and bending stresses, three models of gear pairs are generated and investigated using finite element software package (ANSYS). The profiles of these models are as following: double circular arc for first model, crowned involute for second model, while the third model formed by combining double circular arc with involute crowned profiles. The results of stress analysis show that the generated stresses are lower in the proposed (combined) gear especially when the contact in the circular arc side. Keywords: Generation of gears, versions of Novikov Gears, circular arc gear, crowned involute gear, stress analysis in gears. 1. Introduction: Gears are mostly used to transmit power between shafts in several mechanical applications such that the rotary motion of the driven shaft is perfectly uniform relative to that of driving shaft [1]. In several mechanical applications gearing system is the preferred drive. As we know the toothed gearing has many advantages in compare with other mechanical drives such as its applicability for a wide range of torques and speed ratios, long service life and high reliability, can give constant speed ratio when there is no slipping as well as its small size [2]. These advantages illustrate the importance of developing gear profile. Today, three basic types of teeth profiles are used in gears for power transmission. They are involute, Noviko (or circular arc) and cyc1odial [3, 4]. One of the important causes of gear tooth failure is the presence of large contact and bending stresses in loaded gear tooth. These stresses lead to reduce the overall gear life and can result in tooth failure under loaded conditions [5]. A small reduction in the stresses leads to increase in the fatigue life of the gears considerable. Therefore it is important to find out the method of reducing induced stresses in the gear to increase gears life. Various improvements in gear design have taken place during the last few years such as use of material with improved strength, hardening the surfaces selectively with heat treatment and carburization, and improve the surface finish by shot peening. Many efforts such as using the asymmetric teeth, altering the pressure angle, introducing stress relief feature and using the gear with high contact ratio have been made to improve the strength of the gear [5]. Circular arc gears and crowned profile gears are superior compare with other types of gear profiles and they have higher load carrying capacity. In comparison with involute profile gear, crowned profile gear has a larger contact area, lower noise and vibration, and has a stronger tooth form [6]. Circular arc gears can take three to five times the load on the tooth flanks (in compare with involute gears) without detrimental pitting or wear, They more efficient in power transmission, and They retain lubricants between mating teeth more easily and form a thick oil film. Thus, the wearing of tooth flank is slower [7]. In this paper the asymmetric tooth profiles of two versions of Novikov gears will be used to reduce generated stress and increases gears life. These two profiles are double circular arc and crowned involute profiles. Double circular arc gear has higher bending and contact strength in compare with involute gear for the same parameters. This gear has been widely used in industry machinery [8].

Orthogonally protected chiral β-hydroxy-γ-amino acids can be accessed in >100 g quantities from readily available starting materials and reagents in three to four steps. These chiral synthons contain two adjacent stereocenters along with suitably protected functional groups (O-TBS, N-Boc) for downstream reactivity. Implementation of two existing aldol technologies allows rapid access to all possible stereoisomers of 1. The guiding principles during reaction optimization were reaction scalability and operational efficiency. Conversion of the amino acids to a variety of chiral building blocks in one to two steps demonstrates their synthetic utility.

The J&K state which enjoys far greater status than other states within quasi federal polity of india was one of the 562 princely states in British ruled india. In almost all the cases these princely states surrendered whatever notional sovereignty they had to the new Indian state in exchange for guaranteed privy purses. whereas other Indian states lost their whatever kind of notional  sovereignty  they had by supplementary instruments and by agreeing to the settlement of their position and powers by constituent assembly of india  ,j&k choose to remain a unit of Indian federation only on the terms and conditions specified in instrument of accession .The state of j&k has been accorded asymmetric status under Indian federalism because of the peculiar circumstances under which it acceded to the union of india.

Recently, advances in time-varying quantile modeling have proven effective in financial Value-at-Risk forecasting. Some well-known dynamic conditional autoregressive quantile models are generalized to a fully nonlinear family. The Bayesian solution to the general ...

A series of new highly efficient chiral aliphatic–aromatic diamine catalysts have been designed and successfully applied to the asymmetric Michael addition of cyclohexanone with nitroolefins under solvent-free conditions without any acidic additives. The desired adducts were obtained in high yields with excellent enantio- and diastereoselectivities of syn products (up to >99% ee, >99:1 dr). Chirality 2010. © 2010 Wiley-Liss, Inc

© The Author(s) 2012. This article is published with open access at Springerlink.com Abstract Behavioral economics (BE) examines the implications for decision-mak-ing when actors suffer from biases documented in the psychological literature. This article considers how such biases affect regulatory decisions. The article posits a sim-ple model of a regulator who serves as an agent to a political overseer. The regulator chooses a policy that accounts for the rewards she receives from the political over-seer—whose optimal policy is assumed to maximize short-run outputs that garner political support, rather than long-term welfare outcomes—and the weight the regula-tor puts on the optimal long run policy. Flawed heuristics and myopia are likely to lead regulators to adopt policies closer to the preferences of political overseers than they would otherwise. The incentive structure for regulators is likely to reward those who adopt politically expedient policies, either intentionally (due t...

In this paper, a new asymmetrical multilevel inverter topology (MLI) is proposed with the objectives of using decreased number of semiconductor switches, dc voltage sources, gate driver circuits and dc links. The structure of presented MLI is very simple and modular. The fundamental module of this structure consists of nine semiconductor switches (eight unidirectional and one bidirectional) and four asymmetrical configured DC sources (ratio of 1:2), which can generate 13-level output voltage. To validate the design, a Matlab-Simulink based model is developed. For this paper, a Sinusoidal Pulse Width Modulation (SPWM) is deployed as the switching strategy of the proposed MLI. The circuit model is simulated under pure resistive and inductive loads. It will be shown that the circuit performs well under both loads. Comparison with traditional MLIs and other recently introduced MLIs will be conducted to show the superiority of the proposed MLI in terms of reduced number of devices and lo...

In this paper, the subthreshold swing was observed when the stacked high-k gate oxide was used for a junctionless double gate (JLDG) MOSFET. For this purpose, a subthreshold swing model was presented using the series-type potential model derived from the Poisson equation. The results of the model presented in this paper were in good agreement with the two-dimensional numerical values and those from other papers. Using this model, the variation of the subthreshold swing for the channel length, silicon thickness, gate oxide thickness, and dielectric constant of the stacked high-k material was observed using the dielectric constant as a parameter. As a result, the subthreshold swing was reduced when the high-k materials were used as the stacked gate oxide film. In the case of the asymmetric structure, the subthreshold swing can be reduced than that of the symmetric JLDG MOSFET when the dielectric constant of the bottom stacked oxide film was greater than that of the top stacked oxide film. In the case of the asymmetric structure, the subthreshold swing could be also reduced by applying the bottom gate voltage lower than the top gate voltage.

The objective of this work is to obtain estimations of the amplification factors α and δ used for torsion design of buildings, from experiments. For this study, simple one-storey torsionally unbalanced (TU) steel models were considered. Models consisted of a deck ...

The relationship of drain induced barrier lowering (DIBL) phenomenon and channel length, silicon thickness, and thicknesses of top and bottom gate oxide films is derived for asymmetric junctionless double gate (JLDG) MOSFETs. The characteristics between the drain current and the gate voltage is derived by using the potential distribution model to propose in this paper. In this case, the threshold voltage is defined as the corresponding gate voltage when the drain current is (W/L)×10-7 A, and the DIBL representing the change in the threshold voltage with respect to the drain voltage is obtained. As a result, we observe the DIBL is proportional to the negative third power of the channel length and the second power of the silicon thickness and linearly proportional to the geometric mean of the top and bottom gate oxide thicknesses, and derive a relation such as DIBL=25.15 −3 2 √ 1 • 2 , where is a static feedback coefficients between 0 and 1. The is found to be between 0.5 and 1.0 in this model. The DIBL model of this paper has been observed to be in good agreement with the result of other paper, so it can be used in circuit simulation such as SPICE.