Abstract

Globally, two standard systems are used for gear measurements, making interchangeability between them difficult. The first is the metric system, and the second is the British system. This study employs Visual Basic programming to bridge the gap between the two systems and facilitate conversion of parameters such as the number of teeth, center distance, stress, and standard dimensions. The developed program allows an easy transition from the British system to the more widely used metric system. Additionally, it proposes more appropriate technical terminology for different types of gears, replacing traditional or inaccurate terms, thereby improving precision and consistency in mechanical design applications.

Abstract

The urinary system is one of the most important systems in the human body. Diseases of this system, such as urinary tract infections (UTIs), occur when bacteria infect one or more parts of the urinary tract. Urinary incontinence, on the other hand, is the inability to properly control the bladder muscles, leading to involuntary leakage of urine. This study aims to identify the categories of pregnant and non-pregnant women most affected by urinary tract infections, and to compare which group is more susceptible to infection. Additionally, it seeks to determine whether urinary tract infections could be a contributing factor to contraception among non-pregnant women. The research was conducted at Al-Koon Medical Clinic in Al-Khums, Libya. The total sample consisted of 703 women, including 408 pregnant and 295 non-pregnant participants. The results showed that non-pregnant women exhibited higher levels of sugar, uric acid, ketone, protein, albumin, bacteria, and blood in urine compared to pregnant women. Urine culture analysis revealed that Escherichia coli was the most common pathogen, followed by Klebsiella pneumoniae, and Staphylococcus spp.

Abstract

Traditional ultrasonic methods are commonly used to detect delamination in composite materials. However, recent advanced techniques have enabled the identification of matrix defects even in simple tension-loaded specimens. This study aims to investigate matrix splitting and delamination caused by low-energy impacts on quasi-isotropic carbon/polyetheretherketone (PEEK) laminates using a variety of pulse-echo inspection methods. C-scan imaging at normal incidence is used to detect traditional amplitude and time-of-flight separations, while angled C-scans allow the detection of matrix cracks through the laminate thickness. The results of ultrasonic testing on impacted carbon-fiber reinforced PEEK specimens are presented and compared with X-ray findings to demonstrate the effectiveness and accuracy of the proposed inspection technique.

Abstract

Overloaded vehicles are a major cause of increased pavement damage, leading to higher maintenance costs. In this study, the Pavement Condition Index (PCI) was used as an indicator to assess the condition of road pavements. Pavement condition evaluations were conducted at several locations using ASTM D6433-07 criteria and PCI calculation, with samples taken at distances of 50m, 100m, and 150m. The study found that PCI values accurately predicted regulatory restrictions on overloaded vehicles. The PCI value for a 150-meter distance showed a higher tolerance to heavier loads compared to 50m and 100m. The research highlights that pavement deterioration leads to continuous damage in road networks due to excessive traffic, weather, and lack of maintenance, resulting in higher accident rates and maintenance costs. This study aims to evaluate the effectiveness of PCI as a tool for pavement assessment, examine the impact of sample unit length on results, and provide recommendations for optimizing PCI use in determining when maintenance or rehabilitation is required.

Abstract

This paper examines the chemical and biological weathering factors and their effects on different types of building stones in the ancient city of Sabratha. The study is based on Group 2 of weathering proposed by Fitzner and Heinrichs (1999, 2000, 2004), known as "Discoloration/Deposit." Field observations identified six main weathering forms affecting the building stones of Sabratha Archaeological City: soiling effect, biological colonization, biological colonization with crust, discoloration, loose salt deposits, and hard crust deposits. These included nine specific weathering types such as soiling from anthropogenic impact, soiling by droppings, higher plant colonization, microbiological colonization, colonization forming dark crusts, bleaching, coloration, efflorescence, and formation of light-colored crusts. The degree of damage ranged from non-visible to moderate, with the extent of spread varying from very limited to widespread. The linear and progradational indices of this weathering group also showed damage levels from non-visible to moderate. The findings indicate that both chemical and biological weathering contribute to the ongoing deterioration of the ancient stone structures in Sabratha, highlighting the need for conservation measures to protect the city’s heritage.

Abstract

Environmental pollution appears in various forms and degrees depending on its sources and causes. One of these forms is physical pollution, which involves the alteration of the natural physical values in the environment. In terms of degree, pollution is classified into three levels: acceptable pollution, dangerous pollution (common in industrialized countries), and destructive pollution, which can lead to the collapse of the ecological system. In terms of source, it is divided into natural pollution and pollution resulting from human activities. This study aims to examine the types, causes, and potential mitigation methods of physical pollution. It addresses several forms, including water, air, and soil pollution by physical contaminants, as well as noise, radiation, electromagnetic, thermal, light, and indoor pollution. Pollution has become a global concern, leading to the emergence of international organizations dedicated to addressing this serious issue. Due to the severity of physical pollution and its threat to humanity’s future, the researcher proposes several measures to reduce its impact, including: 1. Promoting environmental awareness. 2. Training qualified professionals in environmental sciences. 3. Enacting strict environmental protection laws. 4. Improving industrial planning, encouraging eco-tourism, and expanding natural reserves.