Digital Repository for University of Tripoli

Scientific Computing is an exciting and growing area that provides an important link between Computer Science and the Engineering and Physical Sciences. Today, computer graphics and geometric modeling are used routinely in science, engineering, business; and entertainment. In this thesis we develop object-oriented techniques and software for computing and visualizing implicitly defined manifolds ("surfaces") that arise a wide range of applications. The software differs from existing software for computing such manifolds in its software architecture. Furthermore, its algorithms are based on numerical continuation methods, rather than on subdivision techniques, which allows its practical application to the computation of two-dimensional manifolds in high-dimensional Euclidean spaces. The overall software provides a graphical user interface, algorithms for computing two-dimensional manifolds in higher-dimensional spaces, and graphics routines to visualize the manifolds.
Youssef Omran Gdura(6-2001)

A study was conducted to determine the effect of three native plants from El-Jabal al ELAkhdar, (Libya) on performance and cecal coliform count of broiler chickens. A total of 1260 one-day-old male Cobb chickens were used in the experiment. The birds were assigned to 7 treatment groups (6 replicates per treatment). The dietary treatments included basal diet with no additive (control), and 6 other dietary treatments (Arbutus pavarii, Salvia officinalis and Zizyphus Vulgaris) each of which was added at the rate of 0.5 g and 1 g/kg of basal diet. Results explicitly revealed that all dietary treatments had a significant effect on body performance of broiler chickens compared to the control with the exception of the dietary treatment of S. officinalis at dosage of 0.5 g/kg that has expressed noticeable reduction in body weight. Coliform counts in the cecum of birds receiving 1% A. pavarii and 1% Z. Vulgaris were significantly lower (P ⩽ 0.05) than those of control group from early weeks of treatments, whereas all plant shows a significant lowering (P ⩽ 0.05) of cecal coliform count during the rest of experiment compared to control group. These results emphasize the potential biotic role of such plants together with the immune modulating effects on treated birds. However, further pharmacological and clinical work should be adopted in the future to present an obvious understandable theory behind the potential beneficial as well as side effects of such natural plants.
A. A. Asheg (12-2015)

The effect of low and high doses of Salmonella enteritidis PT4 (SE) on immunocompetent cells in caecum and spleen of one-day-old chicks was investigated. Subsets of T lymphocytes positive for CD3, CD4, CD8 and B lymphocytes (Bu1b-positive cells) were counted in the caecum after immunohistochemical staining and the relative percentage of these cells in the spleen was analysed using a FACScan cytometer on days 7, 10, 14, 21, and 27 post-inoculation (pi). In the low dose group, the number of CD3+ and CD4+ cells in the caecum had significantly increased at day 10 pi. Both CD8+ and Bu1b+ cells were significantly higher on day 14 pi in this group. In the high-dose group, the number of CD4+ cells had significantly increased at day 7 pi. CD3+, CD8+, and Bu1b+ cells showed prolonged proliferation at days 7 up to 21 pi. Splenic lymphocytes demonstrated significant changes only in the high dose group. The percentage of splenic CD4+ cells was decreased at day 7 pi. A decrease in CD3+ and CD8+ cells was found at day 14 pi in this group.
Abdulatif Asheg(11-2002)

Alkali-activated materials (AAMs) received broad recognition from numerous researchers worldwide and may have potential applications in modern construction. The combined use of AAM and steel fibers are superior to typical binder systems because the matrix and fibers exhibit superior bond strength. The results obtained by various authors have shown that good dispersion of the fibers ensures good interaction between the fibers and the AAM matrix. The tensile strength of FR-AAC is superior to that of Ordinary Portland cement (OPC)-based materials, with the addition of silica fume (SF) being particularly remarkable. However, the tensile strength of fiber-reinforced alkali-activated concrete (FR-AAC) decreases with increasing fiber length. The bond strength increases with the increasing grade of concrete, the roughness of interface, and the solution's strength activated by alkalis. Regardless of fiber type, AAC's modulus of elasticity is linearly correlated with compressive strength. Fibers can affect the modulus of concrete due to the stiffness of the fiber and the porosity of the composite. Poisson's ratio for AAC corresponded to the ASTM C469-14 standard (about 0.22) and decreased to about 0.15–0.21 with silica fume addition. There are limited resources for the experimental Poisson's ratio and it is only estimated using the predictive equations available. Therefore, it is necessary to conduct additional experimental studies to estimate Poisson's ratios for FR-AAC composites. Retention of 59% and 44% in flexural strength during exposure at 800 °C and 1050 °C was observed in the FR-AAC stainless steel composite, and the chopped alumina fibers achieved higher yield strength at these temperatures. For FA-based AAC mortars with 1% SF with a hooked end, activated with a solution of NaOH and sodium silicate, an increase in the number of bends increased the bond strength, load pull-out and maximum pull-out strength. Autogenous shrinkage and drying shrinkage increase with higher silicate content, while shrinkage decreases with higher NaOH concentration. Relatively little research has been completed on FR-AAC in terms of durability or different environmental conditions. In addition, trends of development research toward the broad understanding regarding the application possibilities of FR-AAC as appropriate concrete materials for developing robust and green concrete composites for modern construction were extensively reviewed.
Hakim S. Abdelgader (1-2022)

https://theses.gla.ac.uk/3406/Parallelization has moved in recent years into the mainstream compilers, and the demand for parallelizing tools that can do a better job of automatic parallelization is higher than ever. During the last decade considerable attention has been focused on developing programming tools that support both explicit and implicit parallelism to keep up with the power of the new multiple core technology. Yet the success to develop automatic parallelising compilers has been limited mainly due to the complexity of the analytic process required to exploit available parallelism and manage other parallelisation measures such as data partitioning, alignment and synchronization. This dissertation investigates developing a programming tool that automatically parallelises large data structures on a heterogeneous architecture and whether a high-level programming language compiler can use this tool to exploit implicit parallelism and make use of the performance potential of the modern multicore technology. The work involved the development of a fully automatic parallelisation tool, called VSM, that completely hides the underlying details of general purpose heterogeneous architectures. The VSM implementation provides direct and simple access for users to parallelise array operations on the Cell’s accelerators without the need for any annotations or process directives. This work also involved the extension of the Glasgow Vector Pascal compiler to work with the VSM implementation as a one compiler system. The developed compiler system, which is called VP-Cell, takes a single source code and parallelises array expressions automatically. Several experiments were conducted using Vector Pascal benchmarks to show the validity of the VSM approach. The VP-Cell system achieved significant runtime performance on one accelerator as compared to the master processor’s performance and near-linear speedups over code runs on the Cell’s accelerators. Though VSM was mainly designed for developing parallelising compilers it also showed a considerable performance by running C code over the Cell’s accelerators.
Youssef Omran Gdura(5-2012)

A review of previous array Pascals leads on to a description of the Glasgow Pascal compiler. The compiler is an ISO-Pascal superset with semantic extensions to translate data parallel statements to run on multiple SIMD cores.
Youssef Omran Gdurra, Paul Cockshott, Ciaran Mcreesh, Susanne Oehle(6-2015)

The goal of this study is to investigate groundwater contamination from sewage disposal lake in Enjela area. In the study, twenty nine wells are assigned in seven sectors surrounding the sewage disposal area. The wells cover around 77 square kilometres. During this study, field and laboratory measurements are conducted. The field measurements include determining the location of wells related to the lagoon and the water depth related to mean sea level. The laboratory measurements include chemical and biological analyses for samples collected from the wells and sewage lagoon. Chemical analyses include determination of pH, EC, TDS, K+ , Na+ , Ca2+, Mg2+ , NO3 ˉ , PO4 3- , HCO3ˉ, and Clˉ. The indicators of biological contamination included coliform bacteria, COD, and BOD. According to the conducted analyses and measurements, the following results can be summarized. The study area is distinguished by the natural groundwater movement in the northeast direction. Concerning the chemical pollution, most of the wells are contaminated by potassium especially in the vicinity of sewage lagoon. For biological contamination, the wells are highly contaminated except those are far from lagoon. Due to its location and according to Simpson ratio, the groundwater in the study area is affected by seawater intrusion. Finally, based on this study, some recommendations are listed that might minimize the effect of this pollution if they are implemented. Keywords: Groundwater, aquifer, sewage water, chemical contamination, biological contamination
Ahmed Ibrahim Ekhmaj, Ahmed Abolaid Ganfoud, Nuri Masoud. Elshebani, , (1-2021)

This laboratory study aims to investigate the effect of adding dry grinders of Cactus (Opuntia ficus- indica) and palm leaf bases (Rachis) and commercial soil enhancer (Compost) with different mixing ratios (2.5, 5.0, 7.5%, by weight) on improving hydraulic properties of sandy soil. Hydraulic properties included the water retention capacity, the saturated hydraulic conductivity, and the moisture content at tension values of 0.3, 1, 10 and 15 bar. These properties were estimated at the beginning of the experiment, and after six months, during which moisture and drying cycles had taken place. Through the obtained results, it was found that all additives improved the soil hydraulic properties, so that the values of the soil retention capacity and soil moisture content versus tension increased. On the other hand, all additives reduced the values of the hydraulic conductivity. The results also indicated lack significant effect of time (at the level of 5%). The different mixing ratios did not significantly affect the hydraulic conductivity (at the level of 5%). However, the results showed that the rachis grinders and the mixture consisting of rachis and cactus outperformed in hydraulic properties as compared with other t
د.احمد ابراهيم خماج, د. احمد ابوالعيد قنفود, المنتصر بالله مختار القريقني, , , , (6-2020)