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In this article, we present SHAIP, a secure Hamming distance–based mutual authentication protocol. It allows an unlimited number of authentications by employing an intrinsic Physical Unclonable Function (PUF). PUFs are being increasingly employed for remote authentication of devices. Most of these devices have limited resources. Therefore, the intrinsic PUFs are most suitable for this task as they can be built with little or no modification to the underlying hardware platform. One major drawback of the current authentication schemes is that they expose the PUF response. This makes the intrinsic PUFs, which have a limited number of challenge-response pairs, unusable after a certain number of authentication sessions. Moreover, these schemes are one way in the sense that they only allow one party, the prover, to authenticate herself to the verifier. We propose a symmetric mutual authentication scheme based on secure (privacy-preserving) computation of the Hamming distance between the PUF response from the remote device and reference response stored at the verifier end. This allows both parties to authenticate each other without revealing their respective sets of inputs. We show that our scheme is effective with all state-of-the-art intrinsic PUFs. The proposed scheme is lightweight and does not require any modification to the underlying hardware.

Polymer flooding is a popular enhanced oil recovery method because of its impact on improvement of sweep efficiency. Polymers are non-Newtonian fluids with different behavior at different flow rates. At high shear rate, they reveal shear-thinning behavior, which is the apparent viscosity reduction by increasing shear rate. However, higher shear rate let them become dilatant. Consequently, an increase in shear rate contributes to increase in apparent viscosity and thus decreases the well injectivity of polymer. Hydraulic fracturing reduces mechanical shearing in the vicinity of the wellbore and plays an important role in feasibility of polymer flooding scenarios due to injectivity enhancement and lowering shear rate. A three-dimensional simulator was used to construct a synthetic model of the reservoir with no-flow boundary condition. Results show that induced hydraulic fractures improve recovery factor of homogeneous and heterogeneous reservoirs due to an increase in injectivity of polymer flooding, although in vertically heterogeneous reservoirs, induced fractures are not very effective. The results also show that the induced fractures are more successful in reservoirs with viscous oil.

The flash point of hydrocarbons and petroleum mixtures is important safety-related data for processing and handling of these materials. In this paper, experimentally measured data on flash points of about 140 pure hydrocarbons and petroleum fractions were collected and used to evaluate existing methods for prediction of these data available in the literature. The errors for the available methods varied from 1.6 to 4.9% for pure hydrocarbons and from 3.7 to 11.1% for petroleum fractions. In these methods, parameters such as vapor pressure, boiling point, molecular weight, density, activity coefficient, and composition were used. On the basis of the available methods and simplified relations for vapor pressure prediction, it was found that the ratio of the flash point to the boiling point of hydrocarbon systems and their mixtures is a constant and a value of this constant is about 0.7 when both temperatures are expressed in absolute degrees. The average absolute deviation for this simplified method was 1.7% for pure hydrocarbons and 2.8% for petroleum fractions, which is comparable or better than existing methods.

Naturally fractured reservoirs (NFRs) contribute in large extent to oil and gas production to the ever increasing market demand of fossil energy. It is believed that the vertical displacement of oil during gas injection assisted by gravity drainage (GAGD) is one of the most efficient methods for oil recovery in these reservoirs. Hence, in this work, unconsolidated packed models of cylindrical geometry surrounded by fracture were utilized in order to perform a series of flow visualization experiments during which the contribution of different parameters such as the extent of matrix permeability, physical properties of oil (viscosity, density, and surface tension) and the withdrawal rate was studied. Furthermore, mutual effects of permeability, oil properties, and production rate on oil recovery efficiency through controlled and free fall gravity drainage processes were also investigated. Experimental results obtained from secondary and tertiary recovery experiments demonstrated that decreasing model permeability and increasing oil viscosity during secondary recovery process reduced the recovery efficiency for all production rates, while under tertiary recovery process these phenomena lead to more oil production for all production rates.

In this paper, a paraffinic/naphthenic/aromatic (P/N/A) compositional model is proposed for calculation of the solubilities of light gases such as methane, ethane, carbon dioxide, and hydrogen in various petroleum and coal liquid fractions under different conditions of temperature and pressure. The proposed model uses Scatchard−Hildebrand theory with a corrected value for the solubility parameter of the dissolving gas and characterizes the liquid phase by its P/N/A composition. The results show that, for the fractions studied, the P/N/A composition has an effect on gas solubility. The model correlated the solubilities of gases with an average error of 4.5% when evaluated with 11 fractions and more than 180 data points for a pressure range of 5−250 bar. Corrected solubility parameters for hydrocarbon gases are recommended for their use with petroleum fractions and coal liquids of different P/N/A compositions. The main advantage of the proposed approach is that no experimental data are required to adjust any binary parameter. The approach is of direct use with the values of the solubility parameters reported in this work and characterization parameters of the fraction.

A generalized correlation in terms of the reduced molar refraction (parameter r) is proposed for the calculation of the viscosity of dense hydrocarbon fluids. The input parameters are the refractive index and density at 20 °C, molecular weight, critical temperature, and pressure. For more than 2600 data points used for the evaluation of the proposed correlations, the average deviation for liquids for hydrocarbons from C1 to C20 is about 8%. For saturated gases (Pr < 1), the absolute average deviation is 3.5%, whereas for high-pressure gases (1 < Pr < 10) and for hydrocarbons from C1 to C10 the average deviation is about 11%. A comparison with similar generalized correlations shows that molar refraction is a suitable third parameter for the generalized correlation of transport properties of dense hydrocarbons.

We have sequenced a 1.1-Mb region of human chromosome 22q containing the dosage-sensitive gene(s) responsible for cat eye syndrome (CES) as well as the 450-kb homologous region on mouse chromosome 6. Fourteen putative genes were identified within or adjacent to the human CES critical region (CESCR), including three known genes (IL-17R, ATP6E, and BID) and nine novel genes, based on EST identity. Two putative genes (CECR3 and CECR9) were identified, in the absence of EST hits, by comparing segments of human and mouse genomic sequence around two solitary amplified exons, thus showing the utility of comparative genomic sequence analysis in identifying transcripts. Of the 14 genes, 10 were confirmed to be present in the mouse genomic sequence in the same order and orientation as in human. Absent from the mouse region of conserved synteny are CECR1, a promising CES candidate gene from the center of the contig, neighboring CECR4, and CECR7 and CECR8, which are located in the gene-poor proximal 400 kb of the contig. This latter proximal region, located approximately 1 Mb from the centromere, shows abundant duplicated gene fragments typical of pericentromeric DNA. The margin of this region also delineates the boundary of conserved synteny between the CESCR and mouse chromosome 6. Because the proximal CESCR appears abundant in duplicated segments and, therefore, is likely to be gene poor, we consider the putative genes identified in the distal CESCR to represent the majority of candidate genes for involvement in CES.

In this paper we show application of the refractive index in the estimation of various thermodynamic and physical properties of pure hydrocarbons and undefined petroleum mixtures. In particular, we demonstrate how one can use the refractive index to estimate equation of state parameters, critical constants, the composition of petroleum mixtures, and temperature-dependent properties such as heat capacity, PVT, and transport properties of hydrocarbon fluids. The refractive index is an easily measurable property; however, when it is not available, methods of estimation of this property through other available parameters are also presented.

In this paper simple estimation methods are presented to predict sulfur weight percentage in petroleum fractions and crude oils. Input data needed to use this method are molecular weight, refractive index, and specific gravity (SG). In cases in which molecular weight and refractive index are not available they can be estimated from the boiling point and SG of the fraction using appropriate methods. For crude oils, the C7+ part of the crude mixture was split into several pseudocompounds using the two-parameter distribution model proposed by Riazi (Ind. Eng. Chem. Res. 1997, 36, 4299−4307), and then for each fraction sulfur content was determined. The sulfur content of crude was then determined from its carbon number distribution (or boiling point distribution) and the estimated sulfur content of each pseudocompound. For 132 different fuels and petroleum products with molecular weight ranging from 75 to 1500 and sulfur contents up to 6%, an average deviation of about 0.15% was obtained to estimate sulfur weight percentage from the proposed method. For seven crude oils with sulfur contents up to 2.4%, the proposed methods gave an average deviation of 0.31%.

Cat eye syndrome (CES) is typically associated with a supernumerary bisatellited marker chromosome derived from human chromosome 22pter to 22q11.2. The region of 22q duplicated in the typical CES marker chromosome extends between the centromere and locus D22S36. We have constructed a long-range restriction map of this region using pulsed-field gel electrophoresis and probes to 10 loci (11 probes). The map covers -3.6 Mb. We have also used 15 loci to construct a yeast artificial chromosome contig, which encompasses about half of the region critical to the production of the CES phenotype (centromere to D22S57). Thus, the CES critical region has been mapped and a substantial portion of it cloned in preparation for the isolation of genes in this region.

AbstractIt is shown that by considering the “b” parameter in a cubic equation of state (EOS) as acentric factor/temperature-dependent, liquid densities especially for heavy compounds and the region near the critical point can be estimated more accurately. The proposed equation can also be used for accurate estimation of critical compressibility factors of different compounds, Although the method is applied to Peng-Robinson equation of state (PR-EOS), it can be used for any other cubic equation of state. The proposed method is particularly useful for phase equilibrium calculations of reservoir fluids. The proposed equation requires critical temperature, critical pressure and acentric factor as the input parameters. The proposed equation of stale estimates properties of liquids, vapor-pressure and critical compressibility factors with greater accuracy for pure compounds and mixtures as well as light and heavy compounds found in reservoir fluids.

In this paper, based on a two-parameter distribution model, a method is presented to predict complete property distributions for molecular weight, boiling point, specific gravity, and refractive index of a C7+ fraction. Only three mixture bulk properties such as molecular weight, specific gravity, and refractive index are needed for this technique. If a distillation (TBP) analysis for the fraction is available, then only two bulk properties such as molecular weight and specific gravity (or refractive index) are sufficient. Predicted distributions for various properties are compared with experimental data of some 48 crude samples. The method is also applied for flash vaporization of a Russian crude oil, and predicted distributions for feed, vapor, and liquid streams are compared with actual data. Splitting and lumping schemes of petroleum fractions using the proposed distribution model are also presented by two different aproaches with detailed computational procedures.