A Secure and Verifiable Computation for k-Nearest Neighbor Queries in Cloud

The popularity of cloud computing has increased significantly in the last few years due to scalability, cost efficiency, resiliency, and quality of service. Organizations are more interested in outsourcing the database and DBMS functionalities to the cloud owing to the tremendous growth of big data and on-demand access requirements. As the data is outsourced to untrusted parties, security has become a key consideration to achieve the confidentiality and integrity of data. Therefore, data owners must transform and encrypt the data before outsourcing. In this paper, we focus on a Secure and Verifiable Computation for k-Nearest Neighbor (SVC-kNN) problem. The existing verifiable computation approaches for the kNN problem delegate the verification task solely to a single semi-trusted party. We show that these approaches are unreliable in terms of security, as the verification server could be either dishonest or compromised. To address these issues, we propose a novel solution to the SVC-kNN problem that utilizes the random-splitting approach in conjunction with the homomorphic properties under a two-cloud model. Specifically, the clouds generate and send verification proofs to end-users, allowing them to verify the computation results efficiently. Our solution is highly efficient from the data owner and query issuers’ perspective as it significantly reduces the encryption cost and pre-processing time. Furthermore, we demonstrated the correctness of our solution using Proof by Induction methodology to prove the Euclidean Distance Verification

Ventriculo-Peritoneal Shunt Infections in Infants and Children

Objective: To determine the rate and the type of ventriculoperitoneal (VP) shunt infections in infants and children admitted to King Fahad Hofuf hospital of Al-Ahsaa area at the Eastern Province of Saudi Arabia.Methods: From mid 2003 to end of 2006; VP shunt infection episodes were reviewed. Once infection was suspected, a cerebrospinal fluid (CSF) sample was taken and empirical antibiotics were recommended. Once infection was confirmed, VP shunt was removed and external ventricular drainage (EVD) was inserted until CSF became sterile after which a new shunt was inserted.Results: 25.9% of patients with VP shunts had infections which represents 29.3% of the procedures. 40% of infected patients had recurrent episodes. 59.1% of infections occurred throughout the first two months following insertion. Single pathogen was isolated in each episode. Pseudomonas auerginosa represented 50% of isolated pathogens compared with 18.2% with Staphylococcus epidermidis.Conclusions: There is a high incidence of VP shunt infections in King Fahad Hofuf hospital when compared with other international centres. Gram negative organisms are the most common cause of the infection

On families of convex polytopes with constant metric dimension

AbstractLet G be a connected graph and d(x,y) be the distance between the vertices x and y. A subset of vertices W={w1,w2,…,wk} is called a resolving set for G if for every two distinct vertices x,y∈V(G), there is a vertex wi∈W such that d(x,wi)≠d(y,wi). A resolving set containing a minimum number of vertices is called a metric basis for G and the number of vertices in a metric basis is its metric dimension dim(G). A family G of connected graphs is a family with constant metric dimension if dim(G) is finite and does not depend upon the choice of G in G.In this paper, we study the metric dimension of some classes of convex polytopes which are obtained by the combinations of two different graph of convex polytopes. It is shown that these classes of convex polytopes have the constant metric dimension and only three vertices chosen appropriately suffice to resolve all the vertices of these classes of convex polytopes

Traumatic brain injury in pediatric age group; predictors of outcome in Pediatric Intensive Care Unit

Objective: To determine predictors for outcomes of traumatic brain injury (TBI) in infants and children younger than twelve years admitted to our pediatric intensive care units (PICU).Methods: This is a retrospective cohort study from 2004-5, done at the PICU of King Fahad Hofuf Hospital, Eastern Province, Saudi Arabia. One hundred and six patients with TBI; 65 boys and 41 girls ages 12 or under, with a mean age of 5.7 years, were included. Of them, 11.3% died (Deaths group), 11% survived with neurological deficits (ND-group), and 77% survived with no neurological deficits (NND-group). The potential predictors for death or neurological deficits were examined.Results: 83% of deaths had initial Glascow coma scale (GCS) of ≤ 4/15, 50% of ND had initial GCS ≤ 8 and 27% of NND had GCS < 12. The initial brain CT was abnormal in 92% of deaths and ND groups, but in only 37% of NND. Combined brain pathologies were found in 92% of deaths, 63% of ND and only in 5% of NND. Hypotension was seen in 67% of deaths, 17% ND and only in 1% of NND. Mechanical ventilation was required in all deaths and more than half of ND. Liver enzymes were high in 50% of deaths and 66% of ND but in only 20% of NND. Serum albumin was low in 33% of deaths, 42% of ND and only 1% NND.Conclusion: Glasgow coma score, brain CT findings, combined brain pathologies, hypotension, high liver enzymes and low serum albumin predict outcome after TBI in pediatric age group

A new approach for describing instantaneous line congruence

summary:Based on the E. Study’s map, a new approach describing instantaneous line congruence during the motion of the Darboux frame on a regular non-spherical and non-developable surface, whose parametric curves are lines of curvature, is proposed. Afterward, the pitch of general line congruence is developed and used for deriving necessary and sufficient condition for instantaneous line congruence to be normal. In terms of this, the derived line congruences and their differential geometric invariants were examined

Advanced separation and anaerobic digestion technologies for value-added bioproducts and biofuel from pulp and paper mill wastes

In the first research project, the extraction of hemicellulose from the process water and synthetic hydrolyzate using liquid-liquid extraction (LLE) was examined. Specifically, the effects of the main experimental variables (the type of solvent, hydrolyzate to solvent volume ratio, and pH) on extraction performance were explored. The tested solvents showed varying affinity and selectivity to recover hemicellulose. It was found that the hemicellulose extraction efficiency of n-hexane (71.03%) and tributyl phosphate (TBP) (72.34%) was higher than that of 1-butanol (62.36%), and toluene (67.03%) at a solvent: hydrolyzate volume ratio of 1:3. A pH value of 4.3, a phase ratio of 1:3 mL/mL, and an extraction time of 30 min were considered optimal conditions for hemicellulose extraction. In the second study, the thermophilic submerged anaerobic membrane bioreactor (ThSAnMBR) technology was used for pulp and paper primary sludge treatment, and both biological and membrane performance were evaluated. The biological performance was studied in terms of biogas production, solids reduction, chemical and structural changes of the digestate, and permeate quality under various operating conditions. While the effect of primary sludge on the membrane performance and fouling was systematically investigated. Several experimental parameters were investigated including solids retention time (SRT) (32- 55 days), hydraulic retention time (HRT) (3-8 days), organic loading rates (OLRs) (2.5-6.8 kg-COD/m3d), temperature (50±1°C), membrane fouling and cleaning frequency. Membrane performance was evaluated by monitoring its flux and corresponding transmembrane pressure as well as changes in its chemical and physical properties resulting from operating conditions using Fourier transform infrared (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray analyzer (EDX), contact angle, and pore size measurement. [...

Game chromatic number of Cartesian and corona product graphs

The game chromatic number $\chi_g$ is investigated for Cartesian product $G\square H$ and corona product $G\circ H$ of two graphs $G$ and $H$. The exact values for the game chromatic number of Cartesian product graph of $S_{3}\square S_{n}$ is found, where $S_n$ is a star graph of order $n+1$. This extends previous results of Bartnicki et al. [1] and Sia [5] on the game chromatic number of Cartesian product graphs. Let $P_m$ be the path graph on $m$ vertices and $C_n$ be the cycle graph on $n$ vertices. We have determined the exact values for the game chromatic number of corona product graphs $P_{m}\circ K_{1}$ and $P_{m}\circ C_{n}$