1,642 research outputs found

    Improving Air Interface User Privacy in Mobile Telephony

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    Although the security properties of 3G and 4G mobile networks have significantly improved by comparison with 2G (GSM), significant shortcomings remain with respect to user privacy. A number of possible modifications to 2G, 3G and 4G protocols have been proposed designed to provide greater user privacy; however, they all require significant modifications to existing deployed infrastructures, which are almost certainly impractical to achieve in practice. In this article we propose an approach which does not require any changes to the existing deployed network infrastructures or mobile devices, but offers improved user identity protection over the air interface. The proposed scheme makes use of multiple IMSIs for an individual USIM to offer a degree of pseudonymity for a user. The only changes required are to the operation of the authentication centre in the home network and to the USIM, and the scheme could be deployed immediately since it is completely transparent to the existing mobile telephony infrastructure. We present two different approaches to the use and management of multiple IMSIs

    Effect of algal density in bead, bead size and bead concentrations on wastewater nutrient removal

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    Laboratory experiments were performed to study nitrogen and phosphorus uptake by the unicellular green microalga Chlorella vulgaris immobilized in calcium alginate beads. Different cell stockings inbeads, different bead sizes and different algal bead concentrations in wastewaters were tested. Significant higher nutrients reductions were found in bioreactors containing algal beads than the blankalginate beads (without algae). The bioreactor containing algal beads (4 mm diameter) with 1.5 x 106 cells bead-1 (cell stocking) at concentration of 10.66 beads ml-1 wastewater (1:3 bead: wastewater, v/v) achieved complete removal of NH4 +-N and about 95% reduction in phosphate removal within the experimental period (48 h). Algal uptake and adsorption on alginate gels were the major processesinvolved in the removal of N and phosphate from wastewater. Increasing cell stocking in beads did not cause any improvement in the efficiency of treatment, but caused some leakage problems. Also, increasing the beads concentrations in wastewater caused reductions in light penetration and enhanced self-shading effects and the beads settled at the bottom of the reactor

    Continuous removal and recovery of lead by alginate beads, free and alginate-immobilized Chlorella vulgaris

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    This study examines the possibility of using Chlorella vulgaris cells in repeated lead adsorption/desorption cycles. Alginate beads and immobilized with algal cells were more effective and suitable than free cells. Consistently high lead removal (>90%) and recovery (about 100%) wereachieved. Lead adsorption was mainly via the alginate matrix and minor contribution was made by algae. Free cells were difficult to handle and give inconsistent lead removal and recovery throughout the experiment

    Muslim Student Association General Interest Meeting

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    https://larc.cardozo.yu.edu/flyers-2016-2017/1046/thumbnail.jp

    Informasi Keuangan dan Non Keuangan terhadap Return Saham di Pasar Perdana

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    Financial statement and Non Financial statement need investor at initial market (IPO). The underpricing fenomenal in Initial Public Offering (IPO) is investor get positif return in initial market. The one is caused by asimetry informations in initial market. Investor need some informations, but the informations was getting prospectus informations only. And this research explain to test aboute financial statement and non financial statement to return in initial public offering. The sampling of research were 58 manufacturing and non manufacturing were listing in Bursa Efek Indonesia (Idx) at 2002-2004. Sampling method with purposive sampling. The ones must underpricing and prospectus statement full disclosure. The analyse used multiple regretions. To find relations of auditor reputations, emission guarantor reputation, old age company, equity percentage which on the market, ROA, leverage, industrial sector with initial return. Result of analysis indicate that there is two variable having an effect on significance to initial return that is emission guarantor reputation and auditor reputation. Assess significance T for the auditor reputation is 0.037 meaning significance at 5%. While result of test correlation indicate that emission guarantor reputation variable can explain initial return equal to 0.200 or equal to 20% positive to initial return. This result support research which have been done by Balvers ( 1998) that is emission guarantor reputation and auditor reputation have an effect on negativity significance to initial return. Value of significance T for the emission guarantor reputation is 0.044 meaning significance at a = 5%. Result of examination of this corellation indicate that emission guarantor reputation variable can explain initial return -0.306 or equal to 30.6% negative to initial return. Result of this research support research done by Carter and Dark ( 1992) that emission guarantor reputation, procentage share tender, old age company have an effect on negativity significance to initial return

    Muslim Communities: Borders, Immigrants, and the War on Terror in the Age of Trump

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    https://larc.cardozo.yu.edu/flyers-2016-2017/1014/thumbnail.jp

    Prospect of Indigenous Plant Extracts in Tea Pest Management

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    Tea is a popular beverage made from the leaves of evergreen shrub or tree Camellia sinensis, under the family Theaceae. Tea plant is subjected to the attack of insects, mites, nematodes and some plant pathogenic diseases. Tea production is greatly hindered due to these maladies. About 10-15% crop loss occurred by these pests per annum. In severe cases, it would be 100%. To combat these problems different groups of pesticides have been used in the tea fields since 1960. As tea is a consumable commodity, the effect of residue of pesticides in made tea is harmful to human health. In this context, biopesticides are being considered as environmentally safe, selective, biodegradable, economical and renewable alternatives for use in IPM programmes. Biopesticides are natural plant products and may be grown by the planters with minimum cost and extracted by indigenous methods. Biopesticides are secondary metabolites, which include alkaloids, terpenoids, phenolics, and minor secondary chemicals. It is estimated that as many as 2121 plant species have been reported to posses pest control properties. Botanicals like neem, ghora-neem, mahogoni, karanja, adathoda, sweet flag, tobacco, derris, annona, smart weed, bar weed, datura, calotropis, bidens, lantana, chrysanthemum, artemisia, marigold, clerodendrum, wild sunflower and many others may be grown by planters with minimum expense and extracted by indigenous methods. These botanical materials can be used as an alternative to chemical pesticides. These botanical extracts will help in controlling major pests of tea such as Helopeltis, red spider mite, aphids, thrips, jassid, flushworm, termites, nematodes etc. The present note reviews the information of most widely available indigenous plants that may be used for the control of insect pests of tea as a component of IPM. DOI: http://dx.doi.org/10.3329/ijarit.v1i1-2.13924 Int. J. Agril. Res. Innov. & Tech. 1 (1&2): 16-23, December, 201

    Physico-Chemical Quality Of Drinking Water At Mushait, Aseer, South-Western Saudi Arabia

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    The physico-chemical quality study of different drinking water sources used in Khamis Mushait, southwestern, Saudi Arabia (SA) has been studied to evaluate their suitability for potable purposes. A total of 62 drinking water samples were collected randomly from bottled, desalinated and groundwater located around the study area. The parameters determined in this study were Turbidity; Conductivity; Total solids; pH; Chlorides; Hardness; Sulphate; Ammonia; Nitrite; Nitrate; Iron; Manganese; Copper and Zinc. Most examined parameters were higher in groundwater, followed by desalinated water except for Manganese and Zinc levels. Manganese level was highest in desalinated, followed by bottled water, while Zinc was higher in groundwater than bottled and desalinated water. Most examined groundwater samples had the highest physico-chemical levels as compared with guideline of international and Saudi standards, followed by desalinated and lastly bottled water. Desalinated water showed the higher Manganese value more than the recommended level followed by bottled water, while all the examined water samples had Zinc content lower than the guideline values of international and Saudi standards. Strict hygienic measures should be applied to improve quality of drinking water and to avoid deleterious effect on human health. This could be achieved by working towards a proper monitoring program of drinking water supply and sources Keywords: physico-chemical quality, Drinking Water Quality, Khamis Mushait, Saudi Arabia African Journal of Clinical and Experimental Microbiology Vol. 10 (2) 2009: pp. 117-12

    Analysis of Zero Balancing Case Studies through an Occupational Therapy Lens

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    Does Zero Balancing positively impact occupational performance? This is a question many Occupational Therapists (OTs) ask when discerning if Zero Balancing (ZB) is an evidence-based treatment modality. Case studies from the book Experiencing the Power of Zero Balancing: Case Studies of Journeys to Health and Wholeness (Quarry & King, 2016) were reviewed and compared to the Occupational Therapy domain of practice to show clear evidence that each case study had a positive impact on occupational performance. A comparison chart shows a direct link between the occupational categories and documented evidence of improved occupational performance through practitioner observation and client feedback following ZB treatment

    The Ligand Substitution Reactions of Hydrophobic Vitamin B12 Derivatives. Reaction of Cobyric Acid Heptapropyl Ester with Heterocyclic N-donor Ligands

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    The hydrophobic cobyrinic acid heptapropyl ester corrinoids XCbs-Pr (axial ligand X=CN–, SO32–, CH3– and CH3CH2–) have been prepared from vitamin B12 by hydrolysis of the amide side chains and their conversion to propyl esters. Both the position of the γ-band and the general shape of the UV-visible spectra of these complexes show significant solvent dependence as the polarity of the solvent is varied. The equilibrium constants, K, for the reaction of five-membered heterocyclic nitrogenous bases (the azoles imidazole, pyrazole and 1,2,4-triazole) with displacement of coordinated H2O in aquacyanocobyrinic acid heptapropyl ester, and coordination by the predominantly five-coordinate complexes sulphitocobyrinic acid heptapropyl ester, ethylcobyrinic acid heptapropyl ester and methylcobyrinic acid heptapropyl ester, have been determined spectrophotometrically at 25 °C in water, methanol, acetonitrile, ethyl acetate and toluene. Values of K are dependent on the identity of the trans ligand (X=CN–>SO3 2–> CH3 – > CH3CH2 –); they increase with the basicity of the azole (pyrazole < 1,2,4-triazole < imidazole); and they increase as the solvent polarity increases (toluene<ethyl acetate< acetonitrile< methanol< H2O). Molecular mechanics calculations suggest that these effects are largely electronic in origin.Keywords: Hydrophobic vitamin B12, cobalt corrinoids, equilibrium constants, solvent polarity, trans influencePDF and Supplementry file attache
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