Search results for: Hassan Mohammad Karimi

Authors: Alyaa M. Younes, Nermine Harraz, Mohammad H. Elwany

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Lithium ion batteries are currently used for many applications including satellites, electric vehicles and mobile electronics. Their ability to store relatively large amount of energy in a limited space make them most appropriate for critical applications. Evaluation of the life of these batteries and their reliability becomes crucial to the systems they support. Reliability of Li-Ion batteries has been mainly considered based on its lifetime. However, another important factor that can be considered critical in many applications such as in electric vehicles is the cycle duration. The present work presents the results of an experimental investigation on the degradation behavior of a Laptop Li-ion battery (type TKV2V) and the effect of applied load on the battery cycle time. The reliability was evaluated using an accelerated life test. Least squares linear regression with median rank estimation was used to estimate the Weibull distribution parameters needed for the reliability functions estimation. The probability density function, failure rate and reliability function under each of the applied loads were evaluated and compared. An inverse power model is introduced that can predict cycle time at any stress level given.

Keywords: accelerated life test, inverse power law, lithium-ion battery, reliability evaluation, Weibull distribution

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Authors: Mohammad Hossein Ahmadi, Vahid Haghighatdoost

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Spatial databases have been an active area of research over years. In this paper, we study how to answer the General Time-Dependent Sequenced Route queries. Given the origin and destination of a user over a time-dependent road network graph, an ordered list of categories of interests and a departure time interval, our goal is to find the minimum travel time path along with the best departure time that minimizes the total travel time from the source location to the given destination passing through a sequence of points of interests belonging to each of the specified categories of interest. The challenge of this problem is the added complexity to the optimal sequenced route queries, where we assume that first the road network is time dependent, and secondly the user defines a departure time interval instead of one single departure time instance. For processing general time-dependent sequenced route queries, we propose two solutions as Discrete-Time and Continuous-Time Sequenced Route approaches, finding approximate and exact solutions, respectively. Our proposed approaches traverse the road network based on A*-search paradigm equipped with an efficient heuristic function, for shrinking the search space. Extensive experiments are conducted to verify the efficiency of our proposed approaches.

Keywords: trip planning, time dependent, sequenced route query, road networks

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Authors: Najla M. Salkho, Vinod Paul, Pierre Kawak, Rute F. Vitor, Ana M. Martin, Nahid Awad, Mohammad Al Sayah, Ghaleb A. Husseini

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Liposomes are popular lipid bilayer nanoparticles that are highly efficient in encapsulating both hydrophilic and hydrophobic therapeutic drugs. Liposomes promote a low risk controlled release of the drug avoiding the side effects of the conventional chemotherapy. One of the great potentials of liposomes is the ability to attach a wide range of ligands to their surface producing ligand-mediated active targeting of cancer tumour with limited adverse off-target effects. Ultrasound can also aid in the controlled and specified release of the drug from the liposomes by breaking it apart and releasing the drug in the specific location where the ultrasound is applied. Our research focuses on the synthesis of PEGylated liposomes (contain poly-ethylene glycol) encapsulated with the model drug calcein and studying the effect of low frequency ultrasound applied at different power densities on calcein release. In addition, moieties are attached to the surface of the liposomes for specific targeting of the cancerous cells which over-express the receptors of these moieties, ultrasound is then applied and the release results are compared with the moiety free liposomes. The results showed that attaching these moieties to the surface of the PEGylated liposomes not only enhance their active targeting but also stimulate calcein release from these liposomes.

Keywords: active targeting, liposomes, moieties, ultrasound

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Authors: Gaafar Omer BaOmer, Abdulmohsin A. Al-Sofyani, Hassan A. Ramadan

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Drupella is found on coral reefs throughout the tropical and subtropical shallow waters of the Indo-Pacific region. Drupella is muricid gastropod, obligate corallivorous and their population outbreak can cause significant coral mortality. Belt transect surveys were conducted at two sites (Bohairat and Baydah) in Jeddah coast, Saudi Arabia to assess prey preferences for D. cornus with respect to prey availability through resource selection ratios. Results revealed that there are different levels of prey preferences at the different age stages and at the different sites. Acropora species with a caespitose, corymbose and digitate growth forms were preferred prey for recruits and juveniles of Drupella cornus, whereas Acropora variolosa was avoided by D. cornus because of its arborescent colony growth form. Pocillopora, Stylophora, and Millipora were occupied by Drupella cornus less than expected, whereas massive corals genus Porites were avoided. High densities of D. cornus were observed on two fragments of Pocillopora damicornis which may because of the absence of coral guard crabs genus Trapezia. Mean densities of D. cornus per colony for each species showed significant differentiation between the two study sites. Low availability of Acropora colonies in Bayadah patch reef caused high mean density of D. cornus per colony to compare to that in Bohairat, whereas higher mean density of D. cornus per colony of Pocillopora in Bohairat than that in Bayadah may because of most of occupied Pocillopora colonies by D. cornus were physical broken by anchoring compare to those colonies in Bayadah. The results indicated that prey preferences seem to depend on both coral genus and colony shape, while mean densities of D. cornus depend on availability and status of coral colonies.

Keywords: prey availability, resource selection, Drupella cornus, Jeddah, Saudi Arabia

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Authors: Mohammad Mashud, S. M. Nahid Hasan

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The aim of the research work is to modify the NACA 4215 airfoil with flap and rotary cylinder at the leading edge of the airfoil and experimentally study the static pressure distribution over the airfoil completed with flap and leading-edge vortex generator. In this research, NACA 4215 wing model has been constructed by generating the profile geometry using the standard equations and design software such as AutoCAD and SolidWorks. To perform the experiment, three wooden models are prepared and tested in subsonic wind tunnel. The experiments were carried out in various angles of attack. Flap angle and momentum injection rate are changed to observe the characteristics of pressure distribution. In this research, a new concept of flow separation control mechanism has been introduced to improve the aerodynamic characteristics of airfoil. Control of flow separation over airfoil which experiences a vortex generator (rotating cylinder) at the leading edge of airfoil is experimentally simulated under the effects of momentum injection. The experimental results show that the flow separation control is possible by the proposed mechanism, and benefits can be achieved by momentum injection technique. The wing performance is significantly improved due to control of flow separation by momentum injection method.

Keywords: airfoil, momentum injection, flap, pressure distribution

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Authors: Sanaa K. Bardaweel, Mohammad M. Hudaib, Khaled A. Tawaha, Rasha M. Bashatwah

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Eucalyptus species are well reputed for their traditional use in Asia as well as in other parts of the world; therefore, the present study was designed to investigate the antimicrobial and antioxidant activities associated with essential oils from different Eucalyptus species. Essential oils from the leaves of six Eucalyptus species, including: Eucalyptus woodwardi, Eucalyptus stricklandii, Eucalyptus salubris, Eucalyptus sargentii, Eucalyptus torquata and Eucalyptus wandoo were separated by hydrodistillation and dried over anhydrous sodium sulphate. DPPH, ferric reducing antioxidant power, and hydroxyl radical scavenging activity assays were carried out to evaluate the antioxidant potential of the oils. The results indicate that examined oils exhibit substantial antioxidant activities relative to ascorbic acid. Previously, these oils were evaluated for their antimicrobial activities, against wide range of bacterial and fungal strains, and they were shown to possess significant antimicrobial activities. In this study, further investigation into the growth kinetics of oil-treated microbial cultures was conducted. The results clearly demonstrate that the microbial growth was markedly inhibited when treated with sub-MIC concentrations of the oils. Taken together, the results obtained indicate a high potential of the examined essential oils as bioactive oils, for nutraceutical and medical applications, possessing significant antioxidant and anti microbial activities.

Keywords: antimicrobial, antioxidants, essential (volatile) oil, Eucalyptus

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Authors: Safiqul Islam, Anamul Haque, Mohammad Amran Hossain

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Aim: To compare the dosimetric parameters of the flattened and flattening filter free (FFF) beam and to validate the beam data using anisotropic analytical algorithm (AAA). Materials and Methods: All the dosimetric data’s (i.e. depth dose profiles, profile curves, output factors, penumbra etc.) required for the beam modeling of AAA were acquired using the Blue Phantom RFA for 6 MV, 6 FFF, 10MV & 10FFF. Progressive resolution Optimizer and Dose Volume Optimizer algorithm for VMAT and IMRT were are also configured in the beam model. Beam modeling of the AAA were compared with the measured data sets. Results: Due to the higher and lover energy component in 6FFF and 10 FFF the surface doses are 10 to 15% higher compared to flattened 6 MV and 10 MV beams. FFF beam has a lower mean energy compared to the flattened beam and the beam quality index were 6 MV 0.667, 6FFF 0.629, 10 MV 0.74 and 10 FFF 0.695 respectively. Gamma evaluation with 2% dose and 2 mm distance criteria for the Open Beam, IMRT and VMAT plans were also performed and found a good agreement between the modeled and measured data. Conclusion: We have successfully modeled the AAA algorithm for the flattened and FFF beams and achieved a good agreement with the calculated and measured value.

Keywords: commissioning of a Flattening Filter Free (FFF) , using an Anisotropic Analytical Algorithm (AAA), flattened beam, parameters

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Authors: Sahar Hooshmand, Mohammad Reza Bagherzadeh Anasari

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The aim of this study was to examine the effect of breakfast eating pattern (between frequencies of breakfast consumers and non-consumers) on nutritional status (weight for age, height for age and weight for height). A total 4570 primary school children aged 6-9 years old constituted the sample. From these, 2234 Iranian school children (1218 girls and 1016 boys) and 2336 Indian school children (1096 girls and 1240 boys) were included in a cross sectional study. Breakfast frequency consumption was recorded through an interview with mothers of children. Height and wight of children were taken and body mass index were calculated. The World Health Organization’s (WHO) AnthroPlus software used to assess the nutritional status of the children. Weight for age z-scores were slightly associated with frequency of consuming breakfast in both India (χ2 = 60.083, p=0.000) and Iran (χ2 = 18.267, p=0.032). A significant association was seen between frequency of child‘s breakfast intake and the height z-scores in both India (χ2 = 31.334, p=0.000) and Iran (χ2 = 19.443, p=0.022). Most of children with normal height had breakfast daily in both countries. A significant association was seen with children‘s BMI z-scores of Indian children (χ2 = 31.247, p=0.000) but it was not significant in Iran (χ2 = 10.791, p=0.095). The present study confirms the observations of other studies that showed more frequency in having breakfast is associated with better nutritional status.

Keywords: breakfast, schoolchildren, nutritional status, global food security

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Authors: Mohammad Farooq Wani

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Tribological studies on nano-sized ß-silicon nitride+5% BN were carried out in dry air at high temperatures to clarify the lack of consensus in the bibliographic data concerning the Tribological behavior of Si3N4 ceramics and effect of doped hexagonal boron nitride on coefficient of friction and wear coefficient at different loads and elevated temperatures. The composites were prepared via high energy mechanical milling and subsequent spark plasma sintering using Y2O3 and Al2O3 as sintering additives. After sintering, the average crystalline size of Si3N4 was observed to be 50 nm. Tribological tests were performed with temperature and Friction coefficients 0.16 to 1.183 and 0.54 to 0.71 were observed for Nano-sized ß-silicon nitride+5% BN composite under normal load of 10N-70 N and over high temperature range of 350 ºC-550 ºC respectively. Specific wear coefficients from 1.33x 10-4 mm3N-1m-1 to 4.42x 10-4 mm3N-1m-1 were observed for Nano-sized Si3N4 + 5% BN composite against Si3N4 ball as tribo-pair counterpart over high temperature range of 350 ºC-550 ºC while as under normal load of 10N to70N Specific wear coefficients of 6.91x 10-4 mm3N-1m-1 to 1.70x 10-4 were observed. The addition of BN to the Si3N4 composite resulted in a slight reduction of the friction coefficient and lower values of wear coefficient.

Keywords: ceramics, tribology, friction and wear, solid lubrication

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Authors: Mohammad Khattak, Bikash Adhikari, Sambodh Adhikari

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This research deals with the physical, microstructural, mechanical, and shrinkage characteristics of flyash-based soil-geopolymer mixtures. Medium and high plastic soils were obtained from local construction projects. Class F flyash was used with a mixture of sodium silicate and sodium hydroxide solution to develop soil-geopolymer mixtures. Several mixtures were compacted, cured at different curing conditions, and tested for unconfined compressive strength (UCS), linear shrinkage, and observed under scanning electron microscopy (SEM). The results of the study demonstrated that the soil-geopolymer mixtures fulfilled the UCS criteria of cement treated design (CTD) and cement stabilized design (CSD) as recommended by the department of transportation for pavement base and subbase layers. It was found that soil-geopolymer demonstrated either similar or better UCS and shrinkage characteristics relative to conventional soil-cement mixtures. The SEM analysis revealed that microstructure of soil-geopolymer mixtures exhibited development and steady growth of geopolymerization during the curing period. Based on mechanical, shrinkage, and microstructural characteristics it was suggested that the soil-geopolymer mixtures, has an immense potential to be used as pavement subgrade, subbase, and base layers.

Keywords: soil-geopolymer, pavement base, soil stabilization, unconfined compressive strength, shrinkage, microstructure, and morphology

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Authors: Salam Hadid, Mohammad Khatib

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The International Council of Nurses-ICN defined nursing as a sphere integrating autonomous and collaborative care intended for the individual, family and community within and outside of the care setting. Nursing as a care profession has developed broadly over recent decades in terms of its essentials, expertise and primarily academically. Despite the impressive growth of the profession, there is still extreme diversity in the public’s perceptions and opinions of the profession and its professionals and in the knowledge on the fundamentals of its true function and spheres of engagement. The current study examines the existing knowledge among the general population regarding the nursing profession. The population consisted of 498 respondents, 236 women and 262 men, age 18-81. The respondents noted that nursing focuses on the technical, and the emotional aspects and promotion of health for the patient are not the nurse’s responsibility. Most of the respondents saw nurses working mainly in hospital and community-based clinic settings. They considered nursing to be a high prestige profession in general, but less prestigious among respondents exposed to healthcare provision. Most of the respondents considered nursing to be a humane profession but without independence and with no need for academic studies. The findings are incompatible with the definition of nursing and its spheres of action as defined in the ICN Code of Ethics. Two suggestions are to work through nursing schools addressing the student nurses, as ambassadors for the profession. The second is using the healthcare encounter between the nursing staff and the public to improve the image of nurses.

Keywords: ethics, nurse image, public, nursing

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Authors: Mohammad Hadi Mahmoodi, Azam Ghonchepoor, Sheilan Sohrabi

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The present study was conducted to investigate the effect of foreign language classroom anxiety and ambiguity tolerance on EFL Learners’ listening proficiency. In so doing, 442 EFL learners were randomly selected form Azad University and some accredited language institutions in Hamaden, and were given the Foreign Language Classroom Anxiety Scale (FLCAS) (1983), and Second Language Tolerance of Ambiguity Scale (SLTAS) (1995). Participants’ listening proficiency level was determined through listening scores gained in standardized exams given by university professors or institutes in which they studied English. The results of two-way ANOVA revealed that listening proficiency was significantly affected by the interaction of anxiety and AT level of the participants. Each of the two variables were categorized in three levels of High, Mid, and Low. The highest mean score of listening belonged to the group with low degree of anxiety and high degree of ambiguity tolerance, and the lowest listening mean score was gained by the group with high level of anxiety and low level of tolerance of ambiguity. Also, the findings of multiple regressions confirmed that anxiety was the stronger predictor of listening comprehension in contrast with tolerance of ambiguity. Furthermore, the result of Pearson correlation coefficient showed that there was a significant negative relationship between the participants’ foreign language classroom anxiety and their ambiguity tolerance level.

Keywords: Foreign Language Classroom Anxiety, Second language tolerance of ambiguity, Listening proficiency

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Authors: Mohammad Aynal Haque

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Under the international cooperation — Paris Agreement — countries outline their self-determined policy ambition for emissions reduction in their Nationally Determined Contributions (NDCs) as a key to addressing climate change globally. Although practically all countries commit themselves to reach the Paris landmark (below 20 C) globally, some act as climate leaders, others behave as followers, and others turn out to be climate laggards. As a result, there is a substantial variation in ‘emissions reduction targets’ across countries. Thus, a question emerges: What explains this variation? Or why do some countries opt for higher while others opt for lower ‘emissions reduction targets toward global mitigation efforts? Conceptualizing the ‘emissions reduction targets by 2030’ outlined in NDCs by each country as the climate policy ambition (CPA), this paper explores how certain national political, economic, environmental, and external factors play vital roles in determining climate policy ambition. Based on the cross-country regression analysis among 168 countries, this study finds that democracy, vulnerability to climate change effects, and foreign direct investment have substantial effects on CPA. The paper also finds that resource capacity has a minimal negative effect on CPA across developed countries.

Keywords: climate change, Paris agreement, international cooperation, political economy, environmental politics, NDCs

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Authors: Zainal Arifin, Mohammad Saeri

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The purpose of this study is to determine the efficiency of irrigation use on the growth and yield of two varieties of rice. Water management research on rainfed lowland rice was carried out in dry season (DS I) 2016 in an area of 10,000 m2 in Bunbarat Village, Rubaru Subdistrict, Sumenep Regency. The research was randomized block design factorial with 8 treatments and repeated 3 times, ie Factor I (varieties): (a) Inpago 9, and (b) Sidenuk; factor II (irrigation): (a) Alternate Wetting and Drying, (b) intermittent, (c) submerged, and (d) inundated. The results showed that dominant weed species such as purslane (Portulaca oleraceae L.) and barnyard grass (Echinochloa crusgalli) were mostly found in rice cultivation with Alternate Wetting and Drying, intermittent and submerged irrigation treatment, while the lowest was inundated irrigation. The use of Sidenuk variety with Alternate Wetting and Drying irrigation yielded 5.7 t/ha dry grain harvest (dgh) and was not significantly different from the inundated watering using the Sidenuk variety (6.2 t/ha dgh). With Alternate Wetting and Drying irrigation technique, water use is more efficient as much as 1,503 m3/ha so as to produce 1 kg of grain, it needs 459 liters of water compared to inundated irrigation (665 liters/kg of grain). Results of analysis of rice farming Sidenuk variety with Alternate Wetting and Drying irrigation has the highest B/C ratio (2.56) so that economically feasible.

Keywords: water management, varieties, rice, dry season, rainfed lowland

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Authors: Soodabeh Dehghan, Siavash Hamidzadeh, Naqshbandi Seyyed Salahedin, Ali Mohammad Safania

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The present research with the aim of the relationship between organizational silence and organizational voice with quality of work-life among employees of the sport and youth departments of Tehran Province was done. The statistical population of this research includes all employees of the sport and youth departments of Tehran province, and considering the not very large number of society, the sample and society were considered to be the same, and the sample was considered as the whole number. To measure each of these variables, a questionnaire was used. The research questionnaire was presented in four sections. The results showed that, since the extension of the process of organizational silence is usually done by managers, their attitude and attitudes toward this phenomenon are prioritized and also because silence reduces learning due to lack of knowledge sharing, makes it less effective and makes changes more difficult, it is necessary to take steps to break the silence and to further urge the staff (employees) to express their beliefs (organizational voices) and to share them in the organization's fate individuals, whose beliefs are respected and so called taken into account in the organization, would be dependent on the organization and feel obliged to remain with the organization during the hardships. This affects employees' quality of work life and their satisfaction too much.

Keywords: organizational silence, organizational voice, quality of work life, the sports and youth departments of Tehran province

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Authors: Mohammad Muhebbullah Ibne Hoque, Zheng Jun, Wang Guoying

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Salinity stress is one of the most important abiotic factors contributing to crop growth and yield loss. Exploring the genetic basis is necessary to develop maize varieties with salinity tolerance. In order to discover the inherent basis for salinity tolerance traits in maize, 121 polymorphic SSR markers were used to analyze 163 F2 individuals derived from a single cross of inbred line B73 (a salt susceptible inbred line) and CZ-7 (a salt tolerant inbred line). A linkage map was constructed and the map covered 1195.2 cM of maize genome with an average distance of 9.88 cM between marker loci. Ten salt tolerance traits at seedling stage were evaluated for QTL analysis in maize seedlings. A total of 41 QTLs associated with seedling shoot and root traits were detected, with 16 and 25 QTLs under non-salinity and salinity condition, respectively. And only 4 major stable QTLs were detected in two environments. The detected QTLs were distributed on chromosomes 1, 2, 4, 5, 6, 7, 8, 9, and chromosome 10. Phenotypic variability for the identified QTLs for all the traits was in the range from 6.27 to 21.97%. Fourteen QTLs with more than 10% contributions were observed. Our results and the markers associated with the major QTL detected in this study have the potential application for genetic improvement of salt tolerance in maize through marker-assisted selection.

Keywords: salt tolerance, seedling stage, root shoot traits, quantitative trait loci, simple sequence repeat, maize

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Authors: Morteza Raei Dehaghi, Seyed Mohammad Mirhashemi

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The current study explored the effect of economic development, financial development and institutional quality on environmental destruction in upper-middle income countries during the time period of 1999-2011. The dependent variable is logarithm of carbon dioxide emissions that can be considered as an index for destruction or quality of the environment given to its effects on the environment. Financial development and institutional development variables as well as some control variables were considered. In order to study cross-sectional correlation among the countries under study, Pesaran and Friz test was used. Since the results of both tests show cross-sectional correlation in the countries under study, seemingly unrelated regression method was utilized for model estimation. The results disclosed that Kuznets’ environmental curve hypothesis is confirmed in upper-middle income countries and also, financial development and institutional quality have a significant effect on environmental quality. The results of this study can be considered by policy makers in countries with different income groups to have access to a growth accompanied by improved environmental quality.

Keywords: economic development, environmental destruction, financial development, institutional development, seemingly unrelated regression

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Authors: Tahsin Shameem, Chowdhury Sadman Jahan, Mohammad Alam

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Interest about Net Zero Energy Buildings have gained traction in recent years following the need to sustain energy consumption with generations on site and to reduce dependence on grid supplied energy from large plants using fossil fuel. With this end in view, building integrated photovoltaics are being studied attempting to utilize all exterior facades of a building to generate power. In this paper, we have looked at the physical parameters defining a dye sensitized solar cell (DSSC) and discussed their impact on energy harvest. Following our discussion and experimental data obtained from literature, we have attempted to optimize these physical parameters accordingly so as to allow maximum light absorption for a given active layer thickness. We then modified a planer DSSC design with our optimized properties to allow adequate light transmission which demonstrated a high fill factor and an External Quantum Efficiency (EQE) of greater than 9% by computer aided design and simulation. In conclusion, a DSSC based solar window with such high output values even after such high light transmission through it definitely flags a promising future for this technology and our work elicits the need for further study and practical experimentation.

Keywords: net zero energy building, integrated photovoltaics, dye sensitized solar cell, fill factor, External Quantum Efficiency

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Authors: Amir Mahyar Khorasani, Ian Gibson, Moshe Goldberg, Mohammad Masoud Movahedi, Guy Littlefair

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One of the important factors in manufacturing processes especially machining operations is surface quality. Improving this parameter results in improving fatigue strength, corrosion resistance, creep life and surface friction. The reliability and clearance of removable joints such as thread and nuts are highly related to the surface roughness. In this work, the effect of different cutting parameters such as cutting fluid pressure, feed rate and cutting speed on the surface quality of the crest of thread in the high-speed milling of Brass C3600 have been determined. Two popular neural networks containing MLP and RBF coupling with Taguchi L32 have been used to model surface roughness which was shown to be highly adept for such tasks. The contribution of this work is modelling surface roughness on the crest of the thread by using precise profilometer with nanoscale resolution. Experimental tests have been carried out for validation and approved suitable accuracy of the proposed model. Also analysing the interaction of parameters two by two showed that the most effective cutting parameter on the surface value is feed rate followed by cutting speed and cutting fluid pressure.

Keywords: artificial neural networks, cutting conditions, high-speed machining, surface roughness, thread milling

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Authors: Amir Feily, Hazhir Shahmoradi Akram, Mojtaba Ghaedi, Farshid Javdani, Naser Hatami, Navid Kalani, Mohammad Zarenezhad

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Background: Filler-induced facial skin ischemia is a potential complication of dermal filler injections that can result in tissue damage and necrosis. Nitroglycerin has been suggested as a treatment option due to its vasodilatory effects, but its efficacy in this context is unclear. Methods: A narrative review was conducted to examine the available evidence on the efficacy of nitroglycerin in filler-induced facial skin ischemia. Relevant studies were identified through a search of electronic databases and manual searching of reference lists. Results: The review found limited evidence supporting the efficacy of nitroglycerin in this context. While there were case reports where the combination of nitroglycerin and hyaluronidase was successful in treating filler-induced facial skin ischemia, there was only one case report where nitroglycerin alone was successful. Furthermore, a rat model did not demonstrate any benefits of nitroglycerin and showed harmful results. Conclusion: The evidence regarding the efficacy of nitroglycerin in filler-induced facial skin ischemia is inconclusive and seems to be against its application. Further research is needed to determine the effectiveness of nitroglycerin alone and in combination with other treatments for this condition. Clinicians should consider limited evidence bases when deciding on treatment options for patients with filler-induced facial skin ischemia.

Keywords: nitroglycerin, facial, skin ischemia, fillers, efficacy, narrative review

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Authors: Ghada Shahrour, Nusiebeh Ananbh, Heyam Dalky, Mohammad Rababa, Fatmeh Alzoubi

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Positive teacher-student relationship has been found to affect students’ attitudes towards bullying and, in turn, their engagement in bullying behavior. However, no investigation has been conducted to explore whether teacher-student relationship affects teachers’ attitudes towards bullying. The aim of this study was to examine the role of teacher-student relationship on teachers’ attitudes towards bullying in terms of bullying seriousness, empathic responding, and likelihood to intervene in bullying situation. A cross-sectional, descriptive design was employed among a convenience sample of 173 school teachers (50.9% female) of 12 to 17-year-old students. The teachers were recruited from secondary public schools of three governorates in the Northern district of Jordan. Each group of students has multiple teachers for different subjects. Results showed that teacher-student relationship is partially related to teachers’ attitudes towards bullying. More specifically, having a close teacher-student relationship significantly increased teachers’ perception of bullying seriousness and empathy but not the likelihood to intervene. Research is needed to examine teachers’ obstacles for not providing bullying interventions, as the barriers may be culturally contextualized. Meanwhile, interventions that promote quality teacher-student relationship are necessary to increase teachers’ perception of bullying seriousness and empathy. Students have been found to adopt the values of their teachers, and this may deter them from engaging in bullying behavior.

Keywords: school bullying, teachers’ attitudes, teacher-student relationship, adolescent students

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Authors: Akbar Nawaz Khan, Abdul Ghaffar, Abdur Rehman, Muhammad Naeem Riaz, Sayed Muhammad Hassan Andrabi

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The present study was conducted to compare sheep rearing in nomadic with transhumance system in term of production parameters. The following parameters which studied for comparison were household size, landholding area, flock size, body condition score, fecal egg count and live weight change in sheep under nomadic and transhumance systems of management in Malakand since October 2010 to March 2011. Further the effects of Body Condition Score (BCS) and Fecal Egg Count (FEC) on production were also examined. Two systems were checked for the purpose to check the efficiency of production. A total of eight flocks, four each from nomadic and transhumance system were selected for the study; each flock was divided into treatment and controlled groups to check the effect of treatment or de-wormers. A total of 160 animals were selected randomly (80 treated, 80 controlled). The adult ram average weight transhumance system was 55.58 kg while in nomadic that was 54.16 kg, weight change was positive, and the highest change was recorded in transhumance treated which was 13%. Fecal egg count was record low (75 EPG) in transhumance treated group while high (330 EPG) in nomadic controlled. Body condition score was recorded 3.6 for transhumance treated and 3.32 for nomadic treated. It is concluded from the present study that transhumance system performed significantly (p < 0.05) better in respect of live weight, BCS, FEC, family size, Landholding area, number of animals in a flock, offspring record, culling, and mortality. Mean values are 7.367 ± 0221, 0.900 ± 0.071, 63.167 ± 1.559, 55.600 ± 1.480, 8.300 ± 0.321 and 2.500 ± 0.158 respectively. De-wormer effect on FEC showed a significant reduction in egg load in mature sheep on both systems.

Keywords: small ruminant, sheep, nomadic, transhumance, Malakand, production efficiency

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Authors: Mohammad Besharatloo

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Intrusion detection is an important research topic in network security because of increasing growth in the use of computer network services. Intrusion detection is done with the aim of detecting the unauthorized use or abuse in the networks and systems by the intruders. Therefore, the intrusion detection system is an efficient tool to control the user's access through some predefined regulations. Since, the data used in intrusion detection system has high dimension, a proper representation is required to show the basis structure of this data. Therefore, it is necessary to eliminate the redundant features to create the best representation subset. In the proposed method, a hybrid model of differential evolution and firefly algorithms was employed to choose the best subset of properties. In addition, decision tree and support vector machine (SVM) are adopted to determine the quality of the selected properties. In the first, the sorted population is divided into two sub-populations. These optimization algorithms were implemented on these sub-populations, respectively. Then, these sub-populations are merged to create next repetition population. The performance evaluation of the proposed method is done based on KDD Cup99. The simulation results show that the proposed method has better performance than the other methods in this context.

Keywords: intrusion detection system, differential evolution, firefly algorithm, support vector machine, decision tree

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Authors: Mohammad Saber Rohi, Saghar Heidari

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In this paper, we studied the pricing problem of American options under a regime-switching model with the possibility of a non-optimal exercise policy (early or late exercise time) which is called an irrational strategy. For this, we consider a Markovmodulated model for the dynamic of the underlying asset as an alternative model to the classical Balck-Scholes-Merton model (BSM) and an intensity-based model for the irrational strategy, to provide more realistic results for American option prices under the irrational behavior in real financial markets. Applying a partial differential equation (PDE) approach, the pricing problem of American options under regime-switching models can be formulated as coupled PDEs. To solve the resulting systems of PDEs in this model, we apply a finite element method as the numerical solving procedure to the resulting variational inequality. Under some appropriate assumptions, we establish the stability of the method and compare its accuracy to some recent works to illustrate the suitability of the proposed model and the accuracy of the applied numerical method for the pricing problem of American options under the regime-switching model with irrational behaviors.

Keywords: irrational exercise strategy, rationality parameter, regime-switching model, American option, finite element method, variational inequality

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Authors: Mohammad Karimizadehardakani, Hooman Minoonejad, Reza Rajabi, Ali Sharifnejad

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Background: Ankle sprain is one of the most important risk factor of anterior cruciate ligament (ACL) injury. Also, functional ankle instability (FAI) population has alterations in lower extremity sagittal plane biomechanics during landing task. We want to examine whether biomechanical alterations demonstrated by FAI patients are associated with the mechanism of ACL injury during high risk and sport related tasks. Methods: Sixteen basketball player with FAI and 16 non-injured control performed a single-leg cross drop landing. Knee sagittal and frontal (ATSF) was calculated. Independent t-tests, multiple linear regression, and Pearson correlation were used for analysis data. Result: Subject with FAI showed more peak ATFS, posterior ground reaction force (GRF) and less knee flexion, compared to the controls (P= 0.001, P= 0.004, P= 0.011). Knee flexion (r= −0.824, P = 0.011) and posterior GRF (r= 0.901, P = .001) were correlated with ATSF; Posterior GRF was factor that most explained the variance in ATSF (R2= 0.645; P = .001) in the FAI group. Conclusions: Result of our study showed there is a potential biomechanical relationship between the presence of FAI and risk factors associated with ACL injury mechanism.

Keywords: functional ankle instability, anterior cruciate ligament, biomechanics, risk factor

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Authors: Laila Salah Seada, Ashraf Ibrahim, Fawaz Al Rashid, Ihab Abdo, Hassan Kasim, Waleed Al Mansi, Saud Al Shabli

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Background and Objectives: Colorectal carcinoma is increasing among both men and women worldwide. It has a multifactorial etiology including genetic factors, environmental factors and inflammatory conditions of the digestive tract. A clinicopathologic assessment of colorectal carcinoma in Hail region is done, considering any changing patterns in two 5-year periods from 2005-2009 (A) and from 2012 to 2017 (B). All data had been retrieved from histopathology files of King Khalid Hospital, Hail. Results: During period (A), 75 cases were diagnosed as colorectal carcinoma. Male patients comprised 56/75 (74.7%) of the study, with a mean age of 58.4 (36-97), while females were 19/75 (25.3%) with a mean age of 50.3(30-85) and the difference was significant (p = 0.05). M:F ratio was 2.9:1. Most common histological type was adenocarcioma in 68/75 (90.7%) patients mostly well differentiated in 44/68 (64.7%). Mucinous neoplasms comprised only 7/75 (9.3%) of cases and tended to have a higher stage (p = 0.04). During period (B), 115 cases were diagnosed with an increase of 53.3% in number of cases than period (A). Male to female ratio also decreased to 1.35:1, females being 44.83% more affected. Adenocarcinoma remained the prevalent type (93.9%), while mucinous type was still rare (5.2%). No distal metastases found at time of presentation. Localization of tumors was rectosigmoid in group (A) in 41.4%, which increased to 56.6% in group (B), with an increase of 15.2%. Iliocecal location also decreased from 8% to 3.5%, being 56.25% less. Other proximal areas of the colon were decreased by 25.75%, from 53.9% in group (A) to 40% in group (B). Conclusion: Colorectal carcinoma in Hail region has increased by 53.3% in the past 5 years, with more females being diagnosed. Localization has also shifted distally by 15.2%. These findings are different from Western world patterns which experienced a decrease in incidence and proximal shift of the colon cancer localization. This might be due to better diagnostic tools, population awareness of the disease, as well as changing of life style and/or food habits in the region.

Keywords: colorectal cancer, Hail Region, changing pattern, distal shift

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Authors: Mohammad Abdulaziz Algrnas, Emma Mulliner

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Housing projects have been established in Saudi Arabia, by both government and private construction companies, to meet the increasing demand from Saudi inhabitants across the country. However, the real estate market supply does not meet consumer preference requirements. Preferences normally differ depending on the consumer’s situation, such as the household’s sociological characteristics (age, household size and composition), resources (income, wealth, information and experience), tastes and priorities. Collecting information about consumer attitudes, preferences and perceptions is important for the real estate market in order to better understand housing demand and to ensure that this is met by appropriate supply. The aim of this paper is to identify consumer preferences for housing in Saudi Arabia. A quantitative closed-ended questionnaire was conducted with housing consumers in Saudi Arabia in order to gain insight into consumer needs, current household situation, preferences for a number of investigated housing attributes and consumers’ perceptions around the current housing problem. 752 survey responses were obtained and analysed in order to describe preferences for housing attributes and make comparisons between groups. Factor analysis was also conducted to identify and reduce the attributes. The results indicate a difference in preference according to the gender of the respondents and depending on their region of residence.

Keywords: housing attributes, Saudi Arabia, consumer preferences, housing preferences

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Authors: Mufath Zorgani, Carlos Garcia-Mateo, Mohammad Jahazi

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In this study, the influence of pre-strained austenite on the extent of isothermal bainite transformation in medium-carbon, high-silicon steel was investigated. Different amounts of deformations were applied at 600°C on the austenite right before quenching to the region, where isothermal bainitic transformation is activated. Four different temperatures of 325, 350, 375, and 400°C considering similar holding time 1800s at each temperature, were selected to investigate the extent of isothermal bainitic transformation. The results showed that the deformation-free austenite transforms to the higher volume fraction of CFB bainite when the isothermal transformation temperature reduced from 400 to 325°C, the introduction of plastic deformation in austenite prior to the formation of bainite invariably involves a delay of the same or identical isothermal treatment. On the other side, when the isothermal transformation temperature and deformation increases, the volume fraction and the plate thickness of bainite decreases and the amount of retained austenite increases. The shape of retained austenite is mostly representing blocky-shape one due to the less amount of transformed bainite. Moreover, the plate-like shape bainite cannot be resolved when the deformation amount reached 30%, and the isothermal transformation temperatures are of 375 and 400°C. The amount of retained austenite and the percentage of its transformation to martensite during the final cooling stage play a significant role in the variation of hardness level for different thermomechanical regimes.

Keywords: ausforming, carbide free bainite, dilatometry, microstructure

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Authors: Hind Hassan Arruwaite

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Conceptual metaphor is a cognitive semantic tool that provides access to people's conceptual systems. The correlation in the human conceptual system surpasses limited time and specific cultures. The universal associations provide universal schemas that organize people's conceptualization of the world. The study aims to explore how the cultural associations used in conceptual metaphors create commonalities and harmony between people of the world. In the research methodology, the researcher implemented Critical Metaphor Analysis, Metaphor Candidate Identification and Metaphor Identification Procedure models to deliver qualitative and descriptive findings. The semantic tension was the key criterion in identifying metaphorically used words in the headlines. The research materials are the oil trade conceptual metaphors used in the headlines of Arab News and Saudi Gazette Newspapers. The data will be uploaded to the self-constructed corpus to examine electronic lists for identifying conceptual metaphors. The study investigates the types of conceptual metaphors used in the headlines of the newspapers, the cultural associations identified in the conceptual metaphors, and whether the identified cultural associations in conceptual metaphors create universal conceptual schemas. The study aligned with previous seminal works on conceptual metaphor theory in emphasizing the distinctive power of conceptual metaphors in exposing the cultural associations that unify people's perceptions. The correlation of people conceptualization provides universal schemas that involve elements of human sensorimotor experiences. The study contributes to exposing the shared cultural associations that ensure the commonality of all humankind's thinking mechanism.

Keywords: critical discourse analysis, critical metaphor analysis, conceptual metaphor theory, primary and specific metaphors, corpus-driven approach, universal associations, image schema, sensorimotor experience, oil trade

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Authors: Fateme Mazbanpoor, Sayed Mohammad Amiri

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In this article, we will examine the Persian words in Quran and study the reasons of their presence in this holy book. Writers of this paper extracted about 70 Persian words of Quran by referring to resources. (Alalfaz ol Moarab ol Farsieh Edishir, Almoarabol Javalighi, Almahzab va Etghan Seuti; Vocabulary involved in Quran Arthur Jeffry;, and etc…), some of these words are: ‘Abarigh, ‘Estabragh’,’Barzakh’, ‘Din’,’Zamharir, ‘Sondos’ ‘Sejil’,’ Namaregh’, ‘Fil’ etc. These Persian words have entered Arabic and finally entered Quran in two ways: 1) directly from Persian language, 2) via other languages. The first way: because of the Iranian dominance on Hira, Yemen, whole Oman and Bahrein land in Sasanian period, there were political, religious, linguistic, literary, and trade ties between these Arab territories causing the impact of Persian on Arabic; giving way to many Persian-loan words into Arabic in this period of time. The second way: Since the geographical and business conditions of the areas were dominated by Iran, Hejaz had lots of deals and trades with Mesopotamia and Yemen. On the other hand, Arabic language which was relatively a young language at that time, used to be impressed by Semitic languages in order to expand its vocabulary (Syrian and Aramaic were influenced by the languages of Iran). Consequently, due to the long relationship between Iranian and Arabs, some of the Persian words have taken longer ways through Aramaic and Syrian to find their way into Quran.

Keywords: Quran, Persian word, Arabic language, Persian

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