The Degree of the Teaching Competencies among Social Studies Teachers in Jordan during the Corona pandemic

This study aimed to discover the degree of teaching competencies among social studies teachers in Jordan during the Corona pandemic. The study sample was consisted of (68) teachers for social studies in the governorates of Ma\u27an, Data were calculated through a questionnaire that the researcher built and verified its validity and reliability. In addition, (8) male and female teachers of the study members were interviewed. The results showed that teaching competencies of social studies teachers were middle and there was a negative impact of distance learning on the teaching competencies of social studies teachers during the Corona pandemic. In light of this result, the researcher recommended conducting training courses to develop the teaching competencies of social studies teachers after the end of the Corona pandemic

Compressive Stress-Strain Behavior of Composite Ordinary and Reactive Powder Concrete

The deterioration of reinforced concrete structures is a major social problem. To minimize this problem and ensure effective structural management, the number and extent of repair interventions must be kept at the lowest probable level. Good bond is one of the main requirements for successful repair. The main aim of this study was to investigate the compressive stress-strain behaviour of the composite specimens consist of ordinary concrete (OC) substrate as old concrete and reactive powder concrete (RPC) as a retrofitting material, by using different types of OC substrate surface preparation methods. The results showed that the composite OC/RPC specimens were able to behave closely to individual OC, in the case of using OC substrate with surface prepared by sand blasted

Exploring the Motives of Citizen Reporting Engagement: Self-Concern and Other-Orientation

In smart city contexts, voluntary citizen reporting can be a particularly valuable source of information for local authorities. A key question in this regard is what motivates citizens to contribute their data. Drawing on motivation research in social psychology, the paper examines the question of whether self-concern or other-orientation is a stronger driver of citizen reporting engagement. To test their hypotheses, the authors rely on a sample of users from the mobile application “Zurich as good as new” in Switzerland, which enables citizens to report damages in and other issues with the city’s infrastructure. Data was collected from two different sources: motivation was assessed in an online user survey (n = 650), whereas citizen reporting engagement was measured by the number of reports per user from real platform-use data. The analysis was carried out using negative binomial regression. The findings suggest that both self-concern and other-orientation are significant drivers of citizen reporting engagement, although the effect of self-concern appears to be stronger in comparison. As such, this study contributes to a better understanding of what motivates citizens to participate in citizen reporting platforms, which are a cornerstone application in many smart cities

Effect of different curing conditions on the mechanical properties of UHPFC

(Received: Match 20, 2013; Accepted in Revised Form: June 22, 2013) Abstract: Ultra-High Performance Fiber Concrete (UHPFC) is a new class of concrete. Because of its distinguished mechanical properties, UHPFC is considered as an ideal alternative material for use in developing new structural solutions. This paper discusses on influence of different curing conditions on mechanical properties of UHPFC. An experimental program was performed to study the mechanical properties of UHPFC which were cured under six different curing conditions. Test results indicated that steam and boil curing methods showed a promising performance particularly at early age of curing compared to other type of curing

Pilot Scale for Production and Purification of Lactic Acid from Ceratonia siliqua L. (Carob) Bagasse

The bioconversion of lignocellulose and organic waste bagasse to lactic acid (LA) is an important alternative process requiring valorization as a potentially viable method in the production of pure LA, to be utilized for various purposes. Carob (Ceratonia siliqua L.) biomass was used for the production of LA, using a thermophilic Bacillus coagulans isolate, cultivated in a batch pilot scale of 35 L fermenters without yeast extract supplementation, and operated for 50 h. During the fermentation process, most of the degradable sugar was consumed within 35 h and resulted in the production of 46.9 g/L LA, with a calculated LA yield of 0.72 g/g sugars and productivity at the log phase of 1.69 g/L/h. The use of LA for different industrial applications requires high purity; therefore, a downstream process (DSP) consisting of different purification stages was used, enabling us to reach up to 99.9% (w/w) product purity, which indicates that the process was very effective. The overall almost pure L-LA yield of the DSP was 56%, which indicates that a considerable amount of LA (46%) was lost during the different DSP stages. This is the first study in which carob biomass bagasse has been tested on a pilot scale for LA production, showing the industrial feasibility of the fermentation process

Mechanical properties of old concrete—UHPFC interface

The uniqueness of Ultra-High Performance Fiber Concrete (UHPFC) is its extremely low porosity gives its low permeability and high durability, making it potentially suitable for rehabilitation and retrofitting reinforced concrete structures or for use as a new construction material. This experimental study was performed to assess the bond strength between UHPFC as a repair material and Normal Concrete (NC) substrate as an old material; split tensile strength and slant shear tests were performed to quantify the bond strength in indirect tension and shear respectively, also the correlation between split tensile strength and slant shear were studied. The result showed that UHPFC has been cured by steam, gives high bond strength at the early age of the repair process, and interacts well with the surface of NC, as a result the failure occurred mostly in the NC substrate. A good correlation between the slant shear test results and the split tensile test results has been observed

A Deterministic Algorithm for Arabic Character Recognition Based on Letter Properties

Handheld devices are flooding the market, and their use is becoming essential among people. Hence, the need for fast and accurate character recognition methods that ease the data entry process for users arises. There are many methods developed for handwriting character recognition especially for Latin-based languages. On the other hand, character recognition methods for Arabic language are lacking and rare. The Arabic language has many traits that differentiate it from other languages: first, the writing process is from right to left; second, the letter changes shape according to the position in the work; and third, the writing is cursive. Such traits compel to produce a special character recognition method that helps in producing applications for Arabic language. This research proposes a deterministic algorithm that recognizes Arabic alphabet letters. The algorithm is based on four categorizations of Arabic alphabet letters. Then, the research suggested a deterministic algorithm composed of 34 rules that can predict the character based on the use of all of categorizations as attributes assembled in a matrix for this purpose

Repairing and Strengthening of Damaged RC Columns Using Thin Concrete Jacketing

This research aims to investigate the efficiency of repairing damaged concrete columns using thin concrete jacketing. The experimental program included casting of nine reference 300 mm long reinforced concrete column specimens: three specimens had a cross-sectional dimension of 100 mm × 100 mm, three specimens had a cross-sectional dimension of 150 mm × 150 mm, and three specimens had a cross-sectional dimension of 170 mm × 170 mm. A total of 36 identical column cores were cast with similar cross sections of 100 mm × 100 mm and a height of 300 mm. These cores were damaged by loading them with approximately 90% of their actual ultimate axial load capacities. Then, the columns were repaired and strengthened by applying two jacketing materials, which were 25 and 35 mm thick, on all four sides. Group 1 consisted of 18 column cores jacketed by normal strength concrete with a maximum aggregate size of 4.75 mm and steel reinforcement, whereas Group 2 consisted of 18 column cores jacketed using ultrahigh-performance fibre-reinforced self-compacting concrete with steel reinforcement. The experimental program showed that the Group 1 specimens had ultimate load capacities more than twice those of the unjacketed reference columns and the same axial capacity as the monolithically cast reference columns. The Group 2 specimens showed a significant increase in ultimate load capacity, which was approximately 3 times that of the unjacketed reference column and 1.86 times that of the monolithically cast reference columns. Moreover, using the shear studs was found to be the most effective …This research aims to investigate the efficiency of repairing damaged concrete columns using thin concrete jacketing. The experimental program included casting of nine reference 300 mm long reinforced concrete column specimens: three specimens had a cross-sectional dimension of 100 mm × 100 mm, three specimens had a cross-sectional dimension of 150 mm × 150 mm, and three specimens had a cross-sectional dimension of 170 mm × 170 mm. A total of 36 identical column cores were cast with similar cross sections of 100 mm × 100 mm and a height of 300 mm. These cores were damaged by loading them with approximately 90% of their actual ultimate axial load capacities. Then, the columns were repaired and strengthened by applying two jacketing materials, which were 25 and 35 mm thick, on all four sides. Group 1 consisted of 18 column cores jacketed by normal strength concrete with a maximum aggregate size of 4.75 mm and steel reinforcement, whereas Group 2 consisted of 18 column cores jacketed using ultrahigh-performance fibre-reinforced self-compacting concrete with steel reinforcement. The experimental program showed that the Group 1 specimens had ultimate load capacities more than twice those of the unjacketed reference columns and the same axial capacity as the monolithically cast reference columns. The Group 2 specimens showed a significant increase in ultimate load capacity, which was approximately 3 times that of the unjacketed reference column and 1.86 times that of the monolithically cast reference columns. Moreover, using the shear studs was found to be the most effective

The relationship between substrate roughness parameters and bond strength of ultra high-performance fiber concrete

The bonding that exists between the old concrete and the new concrete depends largely on the quality of substrate surface preparation. The accurate representation of substrate surface roughness can help determine very precisely the correct bonding behavior. In this work, an experimental investigation was carried out to quantify the normal concrete (NC) substrate roughness parameters and evaluate their relationship with the bonding performance of ultra high-performance fiber concrete (UHPFC), used as a repair material. The bond strength was quantified based on the results of the pull-off test, splitting cylinder tensile test, and the slant shear test. Three types of NC substrate surface preparation were used: as-cast (without surface preparation) as reference, wire-brushed, and sand-blasted (SB); the roughness of which was determined using an optical three-dimensional (3D) surface metrology device (Alicona