A Twitter-Based Weighted Reputation system

AbstractTrust between buyers and sellers plays an essential role in online shopping. Therefore, reputation systems are, typically, integrated with online shopping systems to form trust decisions between sellers and buyers. Online Social Networks (OSNs), such as Twitter, LinkedIn, MySpace and Facebook connect people from all over the world in a virtual community. OSNs can provide information about the relationships between people. This information can be used to improve the reliability of reputation systems. With twitter having over than 200 million users and due to its microblogging nature, we choose twitter as a basis for a reputation system

The Level of Advanced Digital Leadership Practice Among Public School Principals in Karak Governorate from the Point of View of the Teachers Themselves

The current study aimed to identify the level of advanced digital leadership practice among public school principals in Karak Governorate from the point of view of the teachers themselves, and to detect differences in the level of digital leadership practice among public school principals according to the variables of gender, experience and educational qualification. The study used the descriptive analytical approach. A questionnaire was developed to measure the level of digital leadership practice among school principals, its validity and reliability indicators were verified, and the study sample consisted of (365) male and female teachers who were randomly selected. Teachers were average, and it was found that there were statistically significant differences in the level of digital leadership practice among public school principals in Karak governorate from the teachers’ point of view due to gender and in favor of females, as well as the presence of differences attributed to experience and in favor of those with higher experience, while the results showed that there were no differences due to educational qualification The study recommended that there should be efforts and measures that should be taken by the Ministry of Education, directorates and schools to develop the level of school principals' practice of digital leadership, such as providing the necessary training and qualification for principals and teachers on the use of technology in education, and providing the necessary resources to improve the digital infrastructure in the school. Which requires the integration of the efforts of the administration, teachers, students and parents to improve the level of digital leadership in schools. Keywords: advanced digital leadership, school principals, public schools DOI: 10.7176/JEP/14-14-04 Publication date:May 31st 202

Synthesis of Specifications and Refinement Maps for Real-Time Object Code Verification

Formal verification methods have been shown to be very effective in finding corner-case bugs and ensuring the safety of embedded software systems. The use of formal verification requires a specification, which is typically a high-level mathematical model that defines the correct behavior of the system to be verified. However, embedded software requirements are typically described in natural language. Transforming these requirements into formal specifications is currently a big gap. While there is some work in this area, we proposed solutions to address this gap in the context of refinement-based verification, a class of formal methods that have shown to be effective for embedded object code verification. The proposed approach also addresses both functional and timing requirements and has been demonstrated in the context of safety requirements for software control of infusion pumps. The next step in the verification process is to develop the refinement map, which is a mapping function that can relate an implementation state (in this context, the state of the object code program to be verified) with the specification state. Actually, constructing refinement maps often requires deep understanding and intuitions about the specification and implementation, it is shown very difficult to construct refinement maps manually. To go over this obstacle, the construction of refinement maps should be automated. As a first step toward the automation process, we manually developed refinement maps for various safety properties concerning the software control operation of infusion pumps. In addition, we identified possible generic templates for the construction of refinement maps. Recently, synthesizing procedures of refinement maps for functional and timing specifications are proposed. The proposed work develops a process that significantly increases the automation in the generation of these refinement maps. The refinement maps can then be used for refinement-based verification. This automation procedure has been successfully applied on the transformed safety requirements in the first part of our work. This approach is based on the identified generic refinement map templates which can be increased in the future as the application required

Permeability and Water Flow in Soils and Sediments

SECTION I Permeability and its measurements. (1) Permeability is defined as the property of a soil which allows the seepage of fluids through its interconnected void spaces. (2) The flow of water through soils is assumed to follow Darcy's law: Q/t = kA H/L where, k = the coefficient of permeability Q = the quantity of water flowing through the soil in time t L = the height of the soil sample A = the area of the cross-section through which the water flows H = the constant head of water (hydraulic head) operating over the height of the soil. (3) Laboratory measurements. The two most common laboratory methods for determining the coefficient of permeability of soils are the following: i) Constant head permeameter. In the constant head test the level of the water is kept constant by addition of water, ii) Variable head permeameter. In this test the level of the water does not remain constant because no water is added to the cylinder containing the sediment. (4) Field measurements. Soil permeability in the field can be measured when the water table is present and when its absent. 4.1 Water table present. Several methods are presently available for the determination of the coefficient of permeability in the field when the water table is present. In my thesis I discussed some of these methods, which are as follows: 4.1.1 Auger hole methods. 4.1.2 Well and pumping method. The determination of the coefficient of permeability is made when water flows through a surface area of 2nrH and when it flows through 2nd. 4.3.1 Multi-layer method. 4.2 Water table absent. Several methods are also available for the determination of the coefficient of permeability in the field when the water table is absent. Some of these methods are as follows: 4.2.1 Particle size method. 4.2.2 Shallow water pumping test. 4.2.4 Pond-Infiltration test. This test, which is an infiltration test over a large area, has been recommended and put into practice to avoid the problem of soil compression which is inherent in core samples. SECTION II Sediment properties influencing permeability. Permeability depends on the characteristics of the soil which are as follows: 1 Particle size. An increase in grain size results an increase in permeability. Two methods for determining the particle size parameters are outlined (I) Graphical analysis. (II) Algebraic analysis. 2 Particle shape. The coefficient of permeability decreases with increasing uniformity of the pore spaces. The effect of particle shape on porosity is discussed using Fraser's experiment. 3 Packing. Permeability is dependent on the packing arrangement, because the tighter the packing density of particles in the soil or sediment the lower its effective porosity and hence the lower its permeability. 4 Void ratio. The void ratio of soils and sediments has an important effect on permeability. When the volume of voids decreases, the permeability also decreases. 5 Composition. Soil composition is of limited importance in the permeability of some soil types such as silts, sands and gravels, but it is of major importance in clays. 6 Fabric. Fabric is one of the most important sediment properties influencing permeability, especially in finegrained soils. Soil samples which are in a flocculated state will have a higher permeability, while the ones in a more dispersed state will have a lower permeability. 7 Degree of saturation. The higher the degree of saturation, the higher the permeability. The relationship between degree of saturation, void ratio and water content have been algebraically solved and illustrated. 8 Biological effects. I have quoted some examples of these effects, such as the effects of intertidal burrowing invertebrates and micro-organisms. SECTION III Soil physics. 1 Water potential. Water is held in the soil against gravitational forces draining water out, or against evaporation of water from the surface of the soil. The energy with which water is held in a soil at any water content is called the water potential. Water flows from where the potential energy is high to where it is low. It moves constantly in the direction of decreasing potential energy. Water potential consists of pressure potential, solute potential and matric potential. The sum of the gravitational potential and the water potential gives the total water potential. 2 Steady state flow in horizontal and vertical direction. In steady state flow, flow characteristics do not change with time, although they may change with location. The rate of flow will depend on the rate of decrease of potential energy in a horizontal and vertical direction. (Abstract shortened by ProQuest.)

Glasgow Coma Scale versus Full Outline of Unresponsiveness Scale in Predicting Discharge Outcomes of Traumatic Brain Injury

Context: Neurological assessment is an essential element of early warning scores used to recognize and early save the lives of critically ill patients.Aim: This study aimed to compare the Full Outline of Unresponsiveness Scale and the Glasgow Coma Scale in predicting discharge outcomes in patients with traumatic brain injury Method: A comparative research design was conducted at the Neurosurgery Intensive Care Unit in El Fayoum University Hospital. The Study recruited a purposive sample of 100 adult patients with TBI. They assessed using three tools (Patients Profile Data Form, Level of Consciousness Assessment," and Tool Discharge Data Assessment Record).Results: GCS is superior to the FOUR score in predicting length of stay and full recovery without any squeal, while they are the same in predicting motor disability and sensory impairment (physical impairment). FOUR score is superior to GCS in the prediction of mortality Conclusion: The FOUR score provides more neurologic details than the GCS and is a valid predictor of outcome in patients with TBI; thus, it could be considered a future prognostic model. It is recommended to use a FOUR score for predicting outcomes in patients with traumatic brain injuries as a valid predictor of discharge outcomes after traumatic brain injury

ENHANCEMENT OF DISSOLUTION AND STABILITY OF CANDESARTAN CILEXETIL–LOADED SILICA POLYMERS

Objective: To prepare stable amorphous solid dispersions of candesartan cilexetil (CAN) with different types of silica, including non-porous (aerosil 200) and porous silica (sylysia 350) using the spray-drying method. Methods: various ratios of candesartan cilexetil (CAN) were spray dried with aerosil and sylysia. Powder x-ray diffraction (x-ray) differential scanning calorimetry (DSC), SEM were used to characterize the spray dried powders in addition to dissolution and stability studies. Results: X-ray results showed that the spray–dried (CAN) in the prepared solid dispersion were in amorphous form irrespective of the used silica. In (DSC) analysis, the melting peak of spray-dried (CAN-silica) solid dispersion disappeared. Dissolution property of (CAN) was remarkably improved by formulating with silica particles. In comparing the effect of the type of the silica particles, the dissolution rate of (CAN) from the spray-dried (CAN-sylysia) was faster than that (CAN-aerosil 200) irrespective of the drug content. It was also shown that the spray-dried formulation with silica did not recrystallize when storing at severe storage conditions (40 °C, 75% RH) for three months, while spray-dried (CAN) without silica easily re-crystallized under the same conditions. Conclusion: Spray drying of (CAN) with sylysia 350 is an efficient method to enhance the dissolution and stability of the drug

Isolation and Identification of Streptomyces from Different Sample of Soils

A total of 36 actinomycetes were isolated and purified from soil samples collected from agricultural soils in Hilla. The isolates were morphologically distinct on the basis of spore mass color, reverse slide color, aerial and substrate mycelia formation and production of diffusible pigment. Only two isolates which were S.A.2 and S.S.10 was selected for further investigation due to its strong antibacterial activity against six pathogenic bacteria which were (Staphylococcus aureus, Escherichia coli, Pseudomonas aeroginosa,Serratiamarcescens, Klebsiella pneumonia, Aeromonashydrophila).These two isolates was identified asStreptomycesorientalisand Streptomyces humidus respectively based on its morphological, cultural, physiological, microscopic features, utilization of carbon sources, biochemical characteristics and  molecular analysis of the 16S rRNA gene primers. Keywords :actinomycetes, spore mass color, 16S rRNA gene primers

Photocatalytic oxidation of butan-2-ol over multi walled carbon nanotubes/cobalt phthalocynanine composites

ABSTRACT. This study involves synthesis of new substituted of cobalt phthalocyanine derivatives (CoPc) from starting materials naphthalene-1,4,5, tetracarbonic acid dianhydride (NDI) and phthalic anhydride by dry process. Nano composites materials were prepared from multi wall carbon nanotubes (MWCNTs), and MO (Cr2O3-NiO) to yield (MWCNTs/MO) nanocomposite and mixed with cobalt phthalocyanine to yield (MWCNTs/CoPc-MO). These materials were investigated using different analytical and spectrophotometric methods such as FTIR spectroscopy, X-rays diffraction (XRD), and scanning electron microscopy (SEM). Then the activity of these materials was investigated by conducting photocatalytic oxidation of butann-2-ol over a suspension of these composites under irradiation with UV light from middle pressure mercury lamp. The concentration of the produced 2-butanone was followed by spectrophotometric method using 2,4-dinitro phenyl hydrazone which was detected by measuring absorbance at 480 nm. Different reaction conditions and parameters were investigated such as effect of weight of the catalyst, temperature of reaction, reaction period and the effect of pH of reaction mixture.                 KEY WORDS: Cobalt phthalocynanine, Nanocomposite, Photocatalytic oxidation of alcohols Bull. Chem. Soc. Ethiop. 2022, 36(1), 197-207.                                                             DOI: https://dx.doi.org/10.4314/bcse.v36i1.16                                                      &nbsp

Evaluation of Bond Strength Between Carbon Fiber Reinforced Polymer (CFRP) Composites with Modified Epoxy Resins and Concrete

Rehabilitation and strengthening of concrete structures are becoming more significant in civil engineering applications. The use of externally bonded Fiber Reinforced Polymers (FRP) is one of the methods to strengthen and rehabilitate reinforced concrete members, providing noticeable improvement to their capacity in resisting load. Carbon Fiber Reinforced Polymer (CFRP) is used along with epoxy resins to evaluate the bond strength of two commercially available epoxies (EPON 828 and EPON 862) between CFRP and concrete. In addition, three new combinations that resulted from mixing the two epoxies were examined. The mechanical properties of epoxy resins are significantly weaker than this of the CFRP making the epoxy characteristics the determining factor in the quality of the bond strength. Three-point flexural test was conducted to examine the bond strength between the CFRP composites and concrete. Further, differential scanning calorimetry was conducted to examine the glass transition temperature of the resultant epoxies. The results showed that the optimum composition was a mixture of 70% of epoxy 828 and 30% of epoxy 862. Therefore, achieving better bond strength and high glass transition temperature, resulting in CFRP composite with higher fire resistance