Design principles for thermally comfortable and low energy homes in the extreme hot-humid climatic Gulf region, with reference to Dammam, Saudi Arabia

Indoor thermal comfort and its consequent energy consumption, are an increasingly important area of consideration in both developed and developing countries. The Gulf States, characterised by their composite extreme hot-humid climate and Airconditioning dependent society are renowned for their high energy consumption. The main aim of this research is to review and report on ways to enhance occupant thermal comfort in homes through improved building and system design and use that minimises energy consumption possible, in the extreme climate of Dammam, Saudi Arabia. The thesis does this by measuring and analysing the thermal performance of the buildings, the thermal satisfaction and comfort responses of their occupants and the energy consumption in them during August 2013 for the summer period and January 2014 for the winter period of the study. The comfort of occupants was assessed using the adaptive thermal comfort method. Neutral indoor air temperatures were, in several homes, surprisingly high. Moreover, most of the studied dwellings do not represent thermally comfortable homes as defined within either PMV or adaptive comfort limits. The study went on to review a broad range of factors that might strongly influence neutral temperatures indoors including the properties of the dwellings, occupant behaviours and attitudes towards high energy demand, loads and costs. The findings are discussed and conclusions drawn on individual design features that contribute to the comfort or discomfort experienced by occupants. It was found that lifestyle, attitudes and other socio-cultural factors have a clear influence on the comfort and in turn energy use in individual dwellings. Although several respondents did not sincerely care about the electricity as it is cheap, in late 2015 the Saudi government hiked the price of domestic energy bills by 60% as a result of low oil prices, putting pressure on many ordinary families to take more notice of their day to day living expenses. The recent electricity price hike provides an economic impetus for the design guidance proffered in the conclusions of this thesis to be taken seriously by householders and implemented by both them and regulating authorities in order to enhance domestic buildings and in turn reduce the CO2 emissions to the global atmosphere. The conclusion of this study is broadly applicable to other regions with similar climatic conditions and cultural contexts such as the Gulf countries

Design of variation-tolerant synchronizers for multiple clock and voltage domains

PhD ThesisParametric variability increasingly affects the performance of electronic circuits as the fabrication technology has reached the level of 32nm and beyond. These parameters may include transistor Process parameters (such as threshold voltage), supply Voltage and Temperature (PVT), all of which could have a significant impact on the speed and power consumption of the circuit, particularly if the variations exceed the design margins. As systems are designed with more asynchronous protocols, there is a need for highly robust synchronizers and arbiters. These components are often used as interfaces between communication links of different timing domains as well as sampling devices for asynchronous inputs coming from external components. These applications have created a need for new robust designs of synchronizers and arbiters that can tolerate process, voltage and temperature variations. The aim of this study was to investigate how synchronizers and arbiters should be designed to tolerate parametric variations. All investigations focused mainly on circuit-level and transistor level designs and were modeled and simulated in the UMC90nm CMOS technology process. Analog simulations were used to measure timing parameters and power consumption along with a “Monte Carlo” statistical analysis to account for process variations. Two main components of synchronizers and arbiters were primarily investigated: flip-flop and mutual-exclusion element (MUTEX). Both components can violate the input timing conditions, setup and hold window times, which could cause metastability inside their bistable elements and possibly end in failures. The mean-time between failures is an important reliability feature of any synchronizer delay through the synchronizer. The MUTEX study focused on the classical circuit, in addition to a number of tolerance, based on increasing internal gain by adding current sources, reducing the capacitive loading, boosting the transconductance of the latch, compensating the existing Miller capacitance, and adding asymmetry to maneuver the metastable point. The results showed that some circuits had little or almost no improvements, while five techniques showed significant improvements by reducing τ and maintaining high tolerance. Three design approaches are proposed to provide variation-tolerant synchronizers. wagging synchronizer proposed to First, the is significantly increase reliability over that of the conventional two flip-flop synchronizer. The robustness of the wagging technique can be enhanced by using robust τ latches or adding one more cycle of synchronization. The second approach is the Metastability Auto-Detection and Correction (MADAC) latch which relies on swiftly detecting a metastable event and correcting it by enforcing the previously stored logic value. This technique significantly reduces the resolution time down from uncertain synchronization technique is proposed to transfer signals between Multiple- Voltage Multiple-Clock Domains (MVD/MCD) that do not require conventional level-shifters between the domains or multiple power supplies within each domain. This interface circuit uses a synchronous set and feedback reset protocol which provides level-shifting and synchronization of all signals between the domains, from a wide range of voltage-supplies and clock frequencies. Overall, synchronizer circuits can tolerate variations to a greater extent by employing the wagging technique or using a MADAC latch, while MUTEX tolerance can suffice with small circuit modifications. Communication between MVD/MCD can be achieved by an asynchronous handshake without a need for adding level-shifters.The Saudi Arabian Embassy in London, Umm Al-Qura University, Saudi Arabi

Genetic variability of camel (Camelus dromedarius) populations in Saudi Arabia based on microsatellites analysis

The genetic diversity and population genetic structure of dromedary camels (Camelus dromedarius) are poorly documented in Saudi Arabia. The present study was conducted to address some of these genetics using four Saudi Arabian camel populations namely; Magaheem (MG), Maghateer (MJ), Sofr (SO) and Shual (SH). Genomic DNA was extracted from the hair roots of 160 camels, 40 individuals from each population. Sixteen microsatellite markers were used to genotype these 160 camels. Out of these 16 markers, only microsatellite VOLP67 did not produce any polymerase chain reaction (PCR) amplicons. There were 139 alleles generated by the 15 microsatellites loci with a mean of 9.27 alleles per locus. Four of the microsatellites loci studied in MG, eight in MJ and six in both SO and SH were found to be deviated from Hardy-Weinberg equilibrium. The fixation genetic indices (Fst) among the four populations were very low, ranging from 0.006 (between SH and SO) to 0.017 (between MG and MJ), indicating low population differentiation among the four Saudi camel populations. No significant heterozygote excess or bottleneck in most nearest past was detected in the four camel populations as indicated by sign, standardized differences and Wilcoxon tests, along with the normal L shaped distribution of mode-shift test. The present study showed that the microsatellite markers are powerful tools in breeding programs, although there is a need for applying more microsatellites in order to be able to discriminate fairly between camel populations of Saudi Arabia.Keywords: Camels, Camelus dromedarius, microsatellite markers, Saudi Arabia, genetic variabilit

Crystal structures of 4-phenylpiperazin-1-ium 6-chloro-5-ethyl-2,4-dioxopyrimidin-1-ide and 4-phenylpiperazin-1-ium 6-chloro-5-isopropyl-2,4-dioxopyrimidin-1-ide

The title molecular salts, C10H15N2+·C6H6ClN2O2−, (I), and C10H15N2+·C7H8ClN2O2−, (II), consist of 4-phenylpiperazin-1-ium cations with a 6-chloro-5-ethyl-2,4-dioxopyrimidin-1-ide anion in (I) and a 6-chloro-5-isopropyl-2,4-dioxopyrimidin-1-ide anion in (II). Salt (I) crystallizes with two independent cations and anions in the asymmetric unit. In the crystal structures of both salts, the ions are linked via N—H...O and N—H...N hydrogen bonds, forming sheets which are parallel to (100) in (I) and to (001) in (II). In (I), the sheets are linked via C—H...Cl hydrogen bonds, forming a three-dimensional framework

Progressive Collapse Resistance of RC Beam–Slab Substructures Made with Rubberized Concrete

Abnormal loads can produce localized damage that can eventually cause progressive collapse of the whole reinforced concrete (RC) structure. This might have devastating financial repercussions and cause numerous severe casualties. Numerical simulation, using the finite element method (FEM), of the consequences of abnormal loads on buildings is thus required to avoid the significant expenses associated with testing full-scale buildings and to save time. In this paper, FEM simulations, using ABAQUS software, were employed to investigate the progressive collapse resistance of the full-scale three-dimensional (3D) beam–slab substructures, considering two concrete mixes, namely: normal concrete (NC) and rubberized concrete (RuC) which was made by incorporating crumb rubber at 20% by volume replacement for sand. The FEM accuracy and dependability were validated using available experimental test results. Concrete and steel material non-linearity were considered in the FE modelling. The numerical study is extended to include eight new models with various specifics (a set of parameters) for further understanding of progressive collapse. Results showed that slabs contribute more than a third of the load resistance, which also significantly improves the building’s progressive collapse resistance. Moreover, the performance of the RuC specimens was excellent in the catenary stage, which develops additional resilience to significant deformation to prevent or even mitigate progressive collapse

Coxiella burnetii, the causative agent of Q fever in Saudi Arabia: molecular detection from camel and other domestic livestock

AbstractObjectiveTo detect Coxiella burnetii (C. burnetii) DNA in clinical specimens from camel, goats, cattle and sheep in the Kingdom of Saudi Arabia.MethodsA total of 367 clinical samples including blood, milk, faeces and urine were collected from different livestock and subjected to PCR amplification using primers which amplify transposon-like region and transposase gene.ResultsPositive amplification from both regions was obtained from camel, goats and cattle but not from sheep. A percentage of 10.8% samples yielded positive PCR amplification from both blood and milk, where 15 of 139 blood and 16 of 148 milk samples were positive. Faeces and urine showed higher percentages of positive samples reaching 40.8% and 23.8% respectively.ConclusionsThe preferred route of shedding in camel appeared to be the faeces followed by urine, while that of goats appeared to be the faeces and that of the cattle appeared to be the milk

The Level of Applying the “NCATE” Standards in the Faculty of Education, University of Khartoum from the Point of View of Faculty Members

هدفت هذه الدراسة التعرف إلى مستوى تطبيق معايير المجلس القومي الأمريكي لاعتماد مؤسسات إعداد المعلمين بكلية التربية بجامعة الخرطوم من وجهة نظر أعضاء هيئة التدريس .وتم استخدام المنهج الوصفي، وبلغ حجم العينة (51) من أعضاء هيئة التدريس، وتم استخدام الاستبانة التي تتكون من (54) فقرة مقسمة إلى (6) مجالات، هي: البرامج المقدمة، ونظام التقييم والتقويم، والتنوع، والخبرة الميدانية، والتنمية المهنية لأعضاء هيئة التدريس، والموارد والحوكمة. وقد تم تحليل البيانات باختبار "ت" لعينة واحدة، واختبار مان-وتيني للفرق بين متوسطات الرتب المستقلة، إضافة إلى تحليل التباين الآحادي. وقد أظهرت النتائج توسط مستوى تطبيق معايير المجلس القومي الأمريكي لاعتماد مؤسسات إعداد المعلمين بكلية التربية بجامعة الخرطوم من وجهة نظر أعضاء هيئة التدريس، وعدم وجود فروق بين الذكور والإناث في تطبيق معايير المجلس القومي الأمريكي لاعتماد مؤسسات إعداد المعلمين بكلية التربية بجامعة الخرطوم من وجهة نظر أعضاء هيئة التدريس عدا مجال نظام التقييم والتقويم، ولصالح الذكور. وفيما يخص متغير الدرجة العلمية فقد أظهرت الدراسة عدم وجود فروق في تطبيق معايير اعتماد مؤسسات إعداد المعلمين بكلية التربية بجامعة الخرطوم من وجهة نظر أعضاء هيئة التدريس وفقاً للدرجة العلمية. وأوصت الدراسة بضرورة إجراء المزيد من الدراسات للتعرف إلى المعوقات التي تحول دون تطبيق معايير المجلس القومي الأمريكي لاعتماد مؤسسات إعداد المعلمين بكلية التربية بجامعة الخرطوم. الكلمات المفتاحية: معايير المجلس القومي الأمريكي لاعتماد مؤسسات إعداد المعلمين، كلية التربية، جامعةالخرطوم، أعضاء هيئة التدريس.This study aimed to identify the level of applying the “NCATE” Standards in the Faculty of Education, University of Khartoum, from the faculty members’ perspective. To achieve this objective, the descriptive method was used by administering a questionnaire on a sample of 51 faculty members. The questionnaire consisted of 54 items divided into 6 fields: Offered Programs, System of Assessment and Evaluation, Diversity, Field Experience, Professional Development of Staff, Resources and Governance. The data were analyzed by using one sample T-test, and Mann-Whitney test for the difference between the independent grade averages, and the analysis of variance. The results showed a moderate level of the “NCATE” Standards in the Faculty of Education, from the faculty members’ perspective. There were no differences between males and females in applying the “NCATE” Standards in the Faculty of Education except in the system of assessment and evaluation in favor of males. Also, there were no differences in the “NCATE” Standards from the faculty members’ perspective attributed to the academic rank. The study recommended conducting more studies about the obstacles of applying the “NCATE” Standards in the Faculty of Education, University of Khartoum. Keywords: NCATE, Faculty of Education, University of Khartoum, the staff

The Main and Most Important Radiological Role in the Future of the Healthcare Management: A Systematic Theoretical Review

This study aimed at exploring the main and most important Radiological role in the future of the healthcare management through a systematic theoretical review.  As radiology plays the key role of jumping in to investigate dis­ease diagnosing, staging, monitoring and following it over time and offering expertise and consultation on disease states. And highlighting that this discipline is now in a stage of profound metamorphosis through out of building the value of radiology and the radiologist, to empower radiologists to be larger contributors to care teams. The study concluded that the current radiology model, though useful in many respects, needs to adapt to changing economic incentives and in one way or another align itself with those of the clinicians radiologists serve.

Trombocitni pokazatelji u jednogrbe deve (Camelus dromedarius)

This communication describes platelet indices including platelet count (PLT), mean platelet volume (MPV), plateletcrit (PCT) and platelet distribution width (PDW), along with parallel red blood cell parameters, in samples from 27 dromedary camels of both sexes. The overall mean values of the platelet parameters were: PLT 319.71 ± 38.6 (x109/L); MPV 5.51 ± 0.08 fL; PCT 0.14 ± 0.02% and PDW 19.50 ± 0.62%. A highly significant correlation was found between PLT and PCT (P≤0.001) in male, female and all camels and a significant correlation between MPV and PDW (P<0.05) in male and all camels. The correlation between platelet parameters and parallel red blood cell parameters, namely: hematocrit (HCT), mean corpuscular volume (MCV) and red cell distribution width (RDW), revealed no significant correlation between RBC and PLT, PCT and HCT or MPV and MCV. However, a highly significant correlation was found between PCT and RDW in all camels (P≤0.005).This is the first report of MPV, PCT, PDW and RWD in dromedaries.Opisani su najčešći trombocitni pokazatelji: broj trombocita (PLT), srednji volumen trombocita (MPV), trombokrit (PCT) i širina krivulje raspodjele po volumenu (PDW), kao i pokazatelji crvenih krvnih stanica u 27 jednogrbih deva oba spola. Prosječne srednje vrijednosti trombocitnih pokazatelja bile su za broj trombocita (PLT) 319,71 ± 38,6×109/L); za srednji volumen trombocita (MPV) 5,51 ± 0,08 fL, trombokrit (PCT) 0,14 ± 0,02% i širinu krivulje raspodjela (PDW) 19,50 ± 0,62%. Značajna korelacija bila je ustanovljena između broja trombocita i trombokrita (P≤0,001) u mužjaka i ženki te općenito u svih pretraženih deva. Također je bila ustanovljena značajna korelacija između srednjega volumena trombocita i širene raspodjele trombocita (P<0,05). Nije ustanovljena korelacija između trombocitnih pokazatelja i pokazatelja crvenih krvnih stanica, tj. usporedbom hematokrita, srednjega volumena crvenih krvnih stanica i raspodjele po volumenu crvenih stanica nije bila ustanovljena značajna korelacija između broja crvenih krvnih stanica te broja trombocita, trombokrita i hematokrita ili srednjega volumena trombocita i srednjega volumena crvenih krvnih stanica. Međutim, značajna korelacija ustanovljena je između trombokrita i krivulje raspodjele po volumenu eritrocita u svih pretraženih deva (P≤0,005). Ovo je prvo izvješće o srednjem volumen trombocita, trombokritu, raspodjeli po volumenu trombocita te raspodjeli po volumenu crvenih krvnih stanica u jednogrbih deva