Planning of Urban Quarters, Districts and Neighbourhoods in Islam’s Holiest City: A Comparative Analytical Study

Global experiences of planning urban areas are characterised by adopting hierarchical structures from large to small structures, i.e. residential quarter (large residential area), residential district and then residential neighbourhood. Each structure is characterised according to the area, the number of people and the services required for targeting a sustainable urban environment. This concept is a milestone in urban planning in Saudi Arabia. The research attempted to discuss the general trend of planning housing projects in Saudi Arabia and the extent of applying the hierarchal concept. Three models were chosen randomly in Makkah, showing such planning hierarchy. These are Al Shawqiyyah, Al Sharaie and Al Rabwah. These projects were planned four decades ago and became a reality. Through comparative analytical methods, findings revealed ambiguity of the hierarchal planning concept in these projects. Further, the traditional neighbourhood concept was prevalent in most neighbourhoods characterised by low-density development in planning but medium and high densities in reality. The problem is getting worse as cities grow horizontally and vertically. Consistent scientific analysis based on practice and continuous meta-analysis was used. The paper calls for the need to change the current premises of housing plans and reorganise the accumulated problems according to global experiences and local standards.

Examples of Pomonoids of Full Transformations of a Poset

In this research, the partially ordered monoid (simple pomonoid) full transformations of a poset O(X) is studied, and some related properties are examined. We show that when the poset X_ is not totally ordered, the pomonoid of all decreasing singular self-maps of a poset X_ (denoted by S^-) and the pomonoid of all increasing singular self-maps of a poset X_ (denoted by S^+) may not be generally isomorphic. Some specific partial ordered relations are considered, and the cardinalities of S^- and S^+ under these relations are found. The set of fixed, decreasing, and increasing points of mapping α in O(X) are also investigated. KEYWORDS Posets, pomonoids, full transformations

Impact of Solvents, Magnesium Oxide and Aluminium Oxide Nanoparticles on the Photophysical Properties of Acridine Orange Dye

Absorption and fluorescence spectroscopy techniques were applied to investigate the photophysical characteristics of acridine orange (AO) dye in solvents that included distilled water, dimethyl sulfoxide (DMSO), acetone and ethanol in various concentrations (1×10-4–1×10-6) M. All of the samples were served at room temperature. The relationships between various parameters describing the strength of optical transitions in atoms and molecules were reviewed. This study expresses various viewpoints by describing how concentration and solvent affect the dye's absorption and fluorescence spectra. The absorption spectra of AO exhibit a band at (490 nm), except for DMSO, which shifts more towards red by 5 nm. The fluorescence spectra show a blue shift in AO aqueous solution around 6 nm until (0.5×10-4) M, followed by a red shift at around 7 nm at (1×10-6) M. There is a blue shift in (1×10-5) M for DMSO at around 4 nm, then a 10 nm red shift in higher concentrations as well as a 9 nm red shift in acetone and 6 nm in ethanol. Adding magnesium oxide nanoparticles (MgO NPs) quenched AO in both absorption and fluorescence spectra, whereas maximum fluorescence and intensity increased when aluminium oxide nanoparticles (Al2O3 NPs) were added to the solution. KEYWORDS Laser dye, absorption spectrum, fluorescence spectrum, MgO NPs, Al2O3 NPs

Synthesis and Characterisation of Structural and Electrical Properties of CuMn2O4 Spinel Compound

CuMn2O4 was synthesized by the solid-state method. MnO2 and CuO were used as precursors. The optimum temperature of synthesis was 850°C. XRD results showed that the prepared compound had a cubic structure with Fd3 ̅m space group. The lattice constant and unit cell volume were a=8.359Å and V=584.14A°3 respectively. The grain size was calculated by the Debye-Scherrer method and was 33.49 nm for CuMn2O4 annealed at 850°C. The experimental density was calculated and compared to the theoretical density. The results were ρt= 5.399 gr/cm3 and ρE = 5.24 gr/cm3. The electrical properties of the compound showed that it behaves like a semiconductor, and the activation energy of the compound was 0.1535 eV. KEYWORDS Activation energy, copper manganite (CuMO), mixed oxide, solid-state reaction, spinel

Efficient and Cost-effective Service Broker Policy Based on User Priority in VIKOR for Cloud Computing

Cloud computing has become a practical solution for processing big data. Cloud service providers have heterogeneous resources and offer a wide range of services with various processing capabilities. Typically, cloud users set preferences when working on a cloud platform. Some users tend to prefer the cheapest services for the given tasks, whereas other users prefer solutions that ensure the shortest response time or seek solutions that produce services ensuring an acceptable response time at a reasonable cost. The main responsibility of the cloud service broker is identifying the best data centre to be used for processing user requests. Therefore, to maintain a high level of quality of service, it is necessity to develop a service broker policy that is capable of selecting the best data centre, taking into consideration user preferences (e.g. cost, response time). This paper proposes an efficient and cost-effective plan for a service broker policy in a cloud environment based on the concept of VIKOR. The proposed solution relies on a multi-criteria decision-making technique aimed at generating an optimized solution that incorporates user preferences. The simulation results show that the proposed policy outperforms most recent policies designed for the cloud environment in many aspects, including processing time, response time, and processing cost. KEYWORDS Cloud computing, data centre selection, service broker, VIKOR, user priorities

Design of A Perfect Metamaterial Absorber for Microwave Applications

In this manuscript, a multi-band and low-profile metamaterial absorber with polarisation independence from 00 to 450 is presented. The proposed metamaterial structure is composed of a single ring with a rectangular patch, consisting of periodic unit cells with a size of 150mm × 250mm × 1.5mm. The structure exhibits three absorption peaks under normal incidence, which cover the X-band. According to the results, the desired material can excellently absorb the electromagnetic wave signal, with an outstanding absorption rate of about 95% at the microwave x-band frequency. The proposed structure shows three absorption bands where two of them exceed 90% absorption level. The results displayed a high Q-factor of 103.5 at a resonance frequency of 8.58 GHz and the figure of merit (FOM) is 98.4, which can be used to enhance the sensor sensing, narrowband band filter and image sensing. The proposed structure is fabricated, and experiments are carried out to validate the design principle. Strong agreements are observed between the measured and the corresponding simulated results.

Nice Bases of QTAG-Modules

A module M over an associative ring R with unity is a QTAG-module if every finitely generated submodule of any homomorphic image of M is a direct sum of universal modules. In this paper, we investigate the class of QTAG-modules having nice basis. It is proved that if H_ω (M) is bounded then M has a bounded nice basis and if H_ω (M) is a direct sum of uniserial modules, then M has a nice basis. We also proved that if M is any QTAG-module, then M⊕D has a nice basis, where D is the h-divisible hull of H_ω (M).

Lexicographic Repair Under Querying Prioritised DL-Lite Knowledge Bases

This article discusses the issue of inconsistency in responses from various DL-Lite knowledge bases. This inconsistency problem is at the origin of several sources of assertions with different levels of reliability. The various solutions proposed in the literature that have to do with retrieving an exhaustive and coherent list of responses are not satisfactory from the point of view of reliability and performance. The solution that we present to solve this problem is articulated around two phases: the first phase consists of interrogating the different knowledge bases to retrieve all of the possible answers, which may be inconsistent and/or contradictory, and the second phase consists in repairing these inconsistencies and/or contradictions. To do this, we propose an approach based on three algorithms that we developed in this framework: a first algorithm for non-defeat repair, a second algorithm for lexicographic repair and a third algorithm for non-defeat repair based on lexicography of possible inconsistent responses. The experimental study carried out on the different data collections, as well as the analysis of the results obtained, confirm the performance of our approach as well as its efficiency in regards to productivity and complexity in terms of execution time.

The Tensor Product of Zero-Divisor Graphs of Variation Monogenic Semigroups

The tensor product of zero-divisor graphs of variation monogenic semigroups Γ(VS_Mn^1) and Γ(VS_Mm^2) is studied. The vertices(x_1^i,x_2^j) and (x_1^k,x_2^f) of the tensor product of this graph are adjacent whenever gcd(i,k)=1,i+k>n,gcd(j,f)=1 ,j+f>m. Some properties of tensor product graphs are obtained, such as girth, diameter, chromatic, clique and domination numbers.

Lesions in the Hippocampus and Substantia Nigra of Wistar Rats’ Brains Induced by Organophosphate Insecticide

As little is known about the neurotoxicity of the histological structure of the brain, this study focuses on the histological side of four- to six-month-old adult Wistar rat brains, which were examined after 0.1 mg\g organophosphate had been administered orally. In this study, the lesions were mainly localized at the hippocampus and substantia nigra (compacta pars) region. Distinct areas of necrotic and apoptotic tissues were detected in the CA1, CA2, and dentate gyrus of the hippocampus and compacta pars of the substantia nigra. Programmed cell death in the dentate gyrus was observed as early as 72 hours after treatment and necrosis of some brain regions. Moreover, Lewy bodies were noticed in the compacta pars of the substantia nigra. The most important symptoms of parkinsonism were observed in the substantia nigra (compacta pars). These were decreased neurons, increased neuronal melanin in the neurons, and increased glial cells. The degeneration of some neurons was reported in the polymorphic and pyramidal layers. The data showed an increase in the density of the axon membrane and several changes to the axis structure, such as the disappearance of the myelin sheath in some areas along the axis.