On the applicability of diploid genetic algorithms in dynamic environments

Diploid genetic algorithms (DGAs) promise robustness as against simple genetic algorithms which only work towards optimization. Moreover, these algorithms outperform others in dynamic environments. The work examines the theoretical aspect of the concept by examining the existing literature. The present work takes the example of dynamic TSP to compare greedy approach, genetic algorithms and DGAs. The work also implements a greedy genetic approach for the problem. In the experiments carried out, the three variants of dominance were implemented and 115 runs proved the point that none of them outperforms the other.     

A review on solar still: a simple desalination technology to obtain potable water

Present review paper presents an overall summarised presentational view of the research work to be discussed on the solar still. The current review paper also includes the infused crisis and struggle for obtaining fresh water for drinking purpose and consumption for other household activities which are a result of the ecological imbalance that has prevailed and is in continuation for past many centuries. It also shows the various tested and applied techniques for freshwater production and their suitability in the usability context in the present scenario of the scarcity of clean water. The use of solar desalination technology is discussed elaborately for a broader consumption to be employed in the current and future works.     

Correlation between the milling time and hydrogen storage properties of ZrCrFe ternary alloy

Laves phases with AB₂ compositions are common type of topologically close packed structure. Furthermore, lave phases are capable of dissolving considerable amounts of ternary alloying additions. ZrCr₂ crystallized in the hexagonal C14 type of structure is one of interesting candidate among them, but it is not used as storage compound due to its excessive stability, at 323 K the equilibrium pressure is only 1.2 kPa. However the substitution of chromium by other elements can modify the crystal structure, the hydriding capacity and dissociation pressure of hydrogen. In this work Fe has been chosen as a substitute material for Cr and ZrCrFe ternary alloy is prepared using arc furnace. The mechanical alloying process has been introduced to produce nanocrystalline material. This paper presents comprehensive study on structural aspects of ball milled ZrCrFe alloy. On comparison of the XRD data, the broadening was found in the peak width with the increase of milling time which is clear indication of refinement of crystallite size. This refinement could also be confirmed from the SEM analysis also. PCT measurements were performed for a temperature range 303 K–373 K.     

Room temperature response and enhanced hydrogen sensing in size selected Pd-C core-shell nanoparticles: Role of carbon shell and Pd-C interface

In the present work, the effect of carbon shell around size selected palladium (Pd) nanoparticles on hydrogen (H₂) sensing has been studied by investigating the sensing response of Pd-C core-shell nanoparticles having a fixed core size and different shell thickness. The H₂ sensing response of sensors based on Pd and Pd-C nanoparticles deposited on SiO₂ and graphene substrate has been measured over a temperature range of 25 °C–150 °C. It is observed that Pd-C nanoparticle sensor shows higher sensitivity with increase in shell thickness and faster response/recovery in comparison to that of Pd nanoparticle samples. Pd-C nanoparticles show room temperature H₂ sensitivity in contrast to Pd nanoparticles which respond only at higher temperatures. Role of carbon shell is also understood by investigating H₂ sensing properties of Pd and Pd-C nanoparticles on graphene substrates. These results show that higher catalytic activity and electronic interaction at Pd-C interface, a complete coverage and protection of Pd surface by carbon and presence of structural defects in nanoparticle core are important for room temperature and higher sensing response.     

Short- and long-term effects of fraternity and sorority membership on heavy drinking: A social norms perspective.

This study sought to determine whether the well-established relation between fraternity/sorority (Greek) membership and heavy alcohol use persists beyond the college years and whether some common third variables might account for the relation between Greek status and heavy drinking. During each of 4 years of college and 1 additional year, young adults (N ?=?319) completed measures of alcohol use, personality, alcohol expectancies, and environmental influences on drinking. Throughout the college years, Greeks consistently drank more heavily than non-Greeks. Statistically controlling for previous alcohol use did not eliminate this effect. However, Greek status did not predict postcollege heavy drinking levels. Also, perceived peer norms for heavy drinking mediated the relation between Greek affiliation and heavy alcohol use. Results are discussed in terms of situational determinants of heavy alcohol involvement in young adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nanocharacterization in Dentistry

About 80% of US adults have some form of dental disease. There are a variety of new dental products available, ranging from implants to oral hygiene products that rely on nanoscale properties. Here, the application of AFM (Atomic Force Microscopy) and optical interferometry to a range of dentistry issues, including characterization of dental enamel, oral bacteria, biofilms and the role of surface proteins in biochemical and nanomechanical properties of bacterial adhesins, is reviewed. We also include studies of new products blocking dentine tubules to alleviate hypersensitivity; antimicrobial effects of mouthwash and characterizing nanoparticle coated dental implants. An outlook on future “nanodentistry” developments such as saliva exosomes based diagnostics, designing biocompatible, antimicrobial dental implants and personalized dental healthcare is presented.     

VMVC: Verifiable multi-tone visual cryptography

Traditional k out of n threshold visual cryptography scheme is proposed to hide a secret image into n shares, where only k or more shares can visually reveal the secret image. Most of the previous state of art approaches on visual cryptography are almost restricted in processing of binary images as secret, which are inadequate for many applications like securely transmission of medical images(Store and Forward Telemedicine), forensic images etc. In this paper, a new Verifiable Multi-toned Visual Cryptography (VMVC) scheme is proposed to securely transmit the confidential images on web. Proposed approach also provides cheating prevention, since each pixel of shares contains a self embedding verifiable bit for integrity test of that pixel. Many existing approaches are suffering from many unnecessary encryption constraints like random shares, codebook requirement, contrast loss etc, which all are successfully addressed in proposed approach. Some comparisons with previously proposed methods are also made. Experimental results and analysis are used to prove the efficiency of proposed approach.     

VPVC: verifiable progressive visual cryptography

In traditional k-out-of-n visual cryptography (VC), a secret image is visually decoded only if a subset of k or more shares are stacked together else nothing will be revealed. Progressive visual cryptography (PVC) scheme differs from the traditional VC where clarity and contrast of the decoded secret image are increased progressively with the number of stacked shares. Shares are most sensible objects since they carry secret; hence, verifying the reliability and authenticity of all shares before decoding the secret image prevents a participant from intentionally or unintentionally providing invalid data. This paper proposes a novel verifiable progressive visual cryptography approach with additional embedding capacity in each share which is used for self-embedding authentication data, copyright information along with confidential payload. These embedded informations in a share can be retrieved and verified at the time of any conflict. Proposed approach also eliminates many unnecessary encryption constraints of VC like pixel expansion, noise-like shares, explicit requirement of codebook and restriction on number of participants. Experiments show that in spite of having various credentials of participants, embedded in shares, the contrast of the decoded secret image remains 50 % without reducing the level of secrecy. By experiments, it is also confirmed that proposed approach can effectively localize the tampered region of the share.     

Structural Determination and Occurrence in Ahiflower Oil of Stearidonic Acid Trans Fatty Acids

Several marine oils and seed oils on the market contain relevant quantities of stearidonic acid (18:4n‐3, SDA). The formation of 18:4n‐3 trans fatty acids (tFA) during the refining of these oils necessitates the development of a method for their quantification. In this study, 18:4n‐3 was isolated from Ahiflower and isomerized to obtain its 16 geometric isomers. The geometric isomers of 18:4n‐3 were isolated by silver ion HPLC (Ag⁺‐HPLC) and characterized by partial reduction with hydrazine followed by gas chromatography analysis. The elution order of all 16 isomers was established using a 100 m × 0.25 mm 100% poly(biscyanopropyl siloxane) capillary column and at the elution temperature of 180 °C. The 4 mono‐trans‐18:4n‐3 isomers produced during the refining of oils rich in 18:4n‐3 were chromatographically resolved from each other, but c6,t9,c12,c15‐18:4 coeluted with the tetra‐cis isomer. These 2 fatty acids (FA) were resolved by reducing the separation temperature to 150 °C, but this change caused tetra‐cis‐18:4n‐3 to coelute with t6,c9,c12,c15–18:4. Combining the results from 2 isothermal separations (180 and 150 °C) was necessary to quantify the 4 mono‐trans 18:4n‐3 FA in Ahiflower oil.