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BVPSMS: A Batch Verification Protocol for End-to-End Secure SMS for Mobile Users
Short Message Service (SMS) is a widely used communication medium for mobile applications, such as banking, social networking, and e-commerce. Applications of SMS services also include real-time broadcasting messages, such as notification of natural disasters and terrorist attacks, and sharing the current whereabouts to other users, such as notifying urgent business meeting information, transmitting quick information in the battlefield to multiple users, notifying current location to our friends, and sharing market information. However, traditional SMS is not designed with security in mind (e.g. messages are not securely sent). In this paper, we introduce a batch verification Authentication and Key Agreement (AKA) protocol, BVPSMS, which provides end-to-end message security over an insecure communication channel between different Mobile Subscribers (MSs). Specifically, the proposed protocol securely transmits SMS from one MS to multiple MS simultaneously. We then evaluate the performance of the BVPSMS protocol in terms of communication and computation overheads, protocol execution time, and batch and re-batch verification times. The impacts of the user mobility, and the time, space, and cost complexity analysis are also discussed. We present a formal proof of the proposed protocol. To the best of our knowledge, this is the first provably-secure batch verification AKA protocol, which provides end-to-end security to the SMS using symmetric keys
Reactive Extraction of Citric Acid Using Different Extractants: Equilibrium, Kinetics and Modeling
Recovery of citric acid from biotechnologically produced low concentration aqueous solution has attracted several separation techniques for the downstream processing. Amongst them, reactive extraction is a convenient, cheap, and effective method. Three
different extractants are used in this study, namely tri-n-butyl phosphate (TBP), tri-n-octylamine (TOA), and Aliquat 336 (A336), all diluted in methyl-iso-butyl ketone (MIBK). The isothermal batch experiments were performed for the equilibrium and kinetic studies
at T = 300.15±1 K. Around 92 % extraction efficiency (E %) was obtained using 20 % (v/v) TOA in MIBK. Based on the overloading of amine (Z > 0.5), (2:1) acid:extractant complex in TOA+MIBK phase was proposed. Kinetics of extraction of citric acid (0.2–0.8 kmol m–3) was also performed in a Lewis-type stirred cell, using TOA in MIBK.
The extraction reaction was occurring in the diffusion film. The second order rate constant was calculated as k2 = 0.0351 m3 kmol–1 s–1. The extraction parameters were estimated by differential evolution optimization technique. Optimal value of equilibrium constant,
KE, was found to be 3.6 · 10–3 (m3 kmol–1)2, for the reactive extraction of citric acid using 20 % TOA in MIBK, and was found in close agreement with experimental values.
This work is licensed under a Creative Commons Attribution 4.0 International License
Study of hyperfragments. Part V. Analysis of light hyperfragments
464 non-mesic and 65 mesic decay of hyperfragments (HFs) produced by pions of momenta 3·5 GeV/c. and 17·2 GeV/c. and protons of momentum 23 GeV/c., have been used to obtain information on Q-, the ratio of non-mesic to π- mesic events and S, the ratio of neutron to proton stimulated events as a function of charge of HFs. Q- is found to increase rapidly with the increase in charge of HFs; the value of Q- for HFs of Z≥3 is 14·6±3·0 which is high compared to the theoretical value of about 4 to 5. The value of S is found to be >1 for all HFs of Z≥2
Study of hyperfragments. Part IV. Mechanism for production of hyperfragments
Hyperfragments (HFs) produced in interactions of high energy pions and protons with emulsion nuclei have been investigated to deduce information on their mechanism of production. From these studies it is concluded that (a) long-range HFs (R≥20µm.) which are due to fragments with mass number 15, are produced in the evaporation stage of the disintegrations of Ag and Br nuclei of emulsion, (b) short-range HFs (R≤10µm.) are mainly due to residues of the target nuclei and a small fraction (≈10%) of them in the range 5<RHF≤15µm. are due to fission type of processes that occur in high energy interactions and (c) the relative probability of sticking of Λ° to fragments with Z=2 to that with 3≤Z≤6 is roughly in the ratio 1:10
Yield Stability in Pigeon pea Hybrids [Cajanus cajan (L.) Millsp.] Under Varying Agro-Climatic Regions
Twelve pigeonpea genotypes comprising ten hybrids and two controls were evaluated at
three environments during rainy season of 2012-13, to study genotype Ă— environment interaction
for yield and related traits. Analysis of variance in each environment and on a pooled basis expressed
a significant difference among genotypes for yield and yield contributing characters except for 100
seed weight. Genotype Ă— environment (linear) interactions were found significant for days to 50%
flowering, plant height, primary and secondary branches per plant, pods per plant, seeds per pod,
grain yield per plant and yield (kg/ha) except days to maturity and 100 seed weight. The regression
and GGE biplot methods were used for analysis. Both methods identified ICPH 2671, ICPH 2740,
ICPH 3933 and ICPH 3762 as stable hybrids. The GGE biplot explained higher proportion of the
mean sum of squares of the GĂ—E interaction and was more informative with regards to environments
and their genotypic performance than the regression method. Hybrids ICPH 2671, ICPH 2740,
ICPH 3762 and ICPH 3933 showed stability for the yield and yield components and could be
recommended for cultivation
The ratio of non-mesic to π<SUP>-</SUP>-mesic decay of light hyperfragments
A new method of obtaining the charge spectrum of light hyperfragments from their residual range distribution is described. This method has been used to determine the ratio (Q-) of non-mesic to π--mesic decay of light hyperfragments. The values of Q- for hyperfragments of different charges are found to be in good agreement with theoretical calculations of Dalitz
Stability of Cytoplasmic Genetic Male Sterility and Fertility Restoration in Pigeonpea
In cytoplasmic genetic male sterility-based (CGMS) hybrid seed
production, instability of expression of male-sterility and fertility
restoration across a wide range of environments are two of the
major difficulties. Therefore, the present study was carried out to
investigate the stability of male sterility of nine CGMS lines under
three dates of sowing and the fertility restoration of 10 CGMS-based
pigeonpea ( Cajanus cajan (L.) Millsp.) hybrids at three different
locations. Significant variability existed for pollen fertility among
hybrids and sterility among cytoplasmic male sterile (CMS) lines.
All the hybrids except ICPH 3494 and ICPH 3491 exhibited high
(>80%) pollen fertility across locations. Hybrids ICPH 2671, ICPH
2740, and ICPH 3933 had 100% male-fertile plants across locations.
All the CMS lines had completely male-sterile plants across
sowing dates. The CMS lines BRG1 A, Hy3C A, BRG3 A, and TTB7 A
exhibited 100% pollen sterility at different sowing dates. The pooled
analysis revealed a significant genotype Ă— environment interaction
for pollen fertility and sterility. The genotypic main effect
+ GE (GGE) biplot of hybrids showed that hybrids ICPH 2671,
2740, 3933, and 3461 were stable for fertility restoration. With the
exception of ICPA 2047 and ICPA 2051, all the CMS lines were
highly stable with high mean performance and least distance from
AEA (average environmental axis). Male-sterility in A4 cytoplasm
was independent of environmental conditions. Different dates of
sowing did not affect expression of male sterility of these CMS lines
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