Combustion of Gaseous Fuels Under Reduced-Gravity Conditions

The need for an improved understanding of fires is becoming critically important with increased space travel and utilization. While the control of fires in low-gravity environments is not well understood, it is known that buoyancy significantly affects flame behavior and characteristics. The objective of this research is to gain a more fundamental understanding of fires, and to quantify flame behavior under reduced-gravity levels. Non-premixed flames of gaseous fuels are considered in this study because they are relatively simple and easy to control, yet embody mechanisms found in all types of combustion processes ranging from uncontrolled fires to practical combustion systems. This paper presents some recent results from microgravity studies of these flames. In addition, the potential usefulness of lunar- and Martian-based laboratories is discussed in order to understand the characteristics and behavior of fires in reduced-gravity environments

Exploring the Relationship between Green IT Awareness and Adoption: A Case Study of IT Students in the Gaza Strip

Green computing, also known as GIT, has emerged as a crucial field in response to environmental concerns. This study focuses on assessing the level of GIT awareness and adoption among IT students at Al-Aqsa University in Gaza, as well as examining the relationship between GIT awareness and adoption. Data was collected through an online questionnaire completed by 273 participants. The questionnaire covered various aspects of GIT awareness, including understanding, environmental awareness, and e-waste awareness. The collected data was analyzed using statistical techniques such as principal component analysis, mean, and standard deviation. The results indicated that students possessed a satisfactory level of understanding of GIT concepts and the reasons for its adoption. Furthermore, the findings highlighted the significant impact of GIT awareness factors, including GIT understanding, environmental awareness, and e-waste awareness, on GIT adoption. However, it was observed that students did not consistently adhere to GIT guidelines, particularly in terms of frequent internet access and extended computer usage. Interestingly, no significant relationship was found between GIT adoption and students' academic standing. These findings provide valuable insights into the current state of GIT awareness and adoption among IT students and underscore the need for further efforts to promote sustainable computing practices

Landslide Hazards : Geotechnical Aspects and Management Policies

The landslides that frequently occur in the hilly areas in Jordan, particularly along the roads and highway routes during the years of intense rainfalls, resulted in a substantial increase in the cost of projects and delay in their completion, in addition to the deportation of people affected or endangered by landslides from their homes. The paper discusses the common characteristics of the landslide-prone areas in Jordan as well as the main causes of slides and their consequences. It discusses the role of site investigation and monitoring systems in reducing the hazard intensity as well as the total cost of construction. Classification of landslideprone areas, according to the level of risk and cost of prevention/mitigation measures into prohibitive, restricted and regulated areas is suggested. This classification aims at controlling the construction activities in the areas susceptible to landslides risks. The different components of landslide risk management are defined and discussed with the suggestion of establishing a National Hazard Management Board to be responsible for drafting of landslides risk management policies

Parametric Evaluation of the Stability of Natural Slopes

A new geotechnical criterion called the Slope Stability Index, SSI, is proposed to be used for the assessment of the relative stability of natural slopes. This criterion involves the calculation of 11 factors in addition to the Rock Mass Rating (RMR). The author has added to the RMR of Bieniawski (1979) two new parameters; namely: the geodurability of the slope material and the geologic setting of the slope. The relative weights of the parameters in the RMR have been adjusted based on experience and judgement. The parameters F1, F2 and F3 related to the joint – slope relationship as well as F4 related to the method of excavation that were introduced by Romana (1996) in his SMR were also adjusted. The new parameters introduced by the author are related to the slope geometry (steepness and shape) and to the environmental factors (rainfall, drainage, climatic and seismic conditions). Zuyu factor E (1995) related to slope height was also introduced with suggested upper and lower values. The new index is believed to give a fair assessment of the relative stability of the slopes under consideration. This would help planners and engineers in their selection of the sites of their engineering projects and in the treatment of slopes that exist in a critical state of stability

Evaluating Indices of Delayed Cerebral Ischemia and Poor Outcomes after Subarachnoid Hemorrhage: The Role of Cerebral Perfusion Pressure in Disease Pathogenesis

Background and Purpose: Delayed cerebral ischemia (DCI) and Hunt and Hess (HH) grade are known risk factors for poor outcomes after aneurysmal subarachnoid hemorrhage (aSAH). DCI is often attributed to focal perfusion deficit (vasospasm/infarction). Global perfusion deficit (e.g. inadequate cerebral perfusion pressure (CPP)) can impair cerebral blood flow (CBF). The relationship between CPP and DCI remains unclear. Further, the exact mechanism of how HH grade relates to poor outcomes is uncertain. This study aimed to describe the temporal profiles of CPP change and to investigate the relationship between CPP, DCI, HH, and post-aSAH outcomes. Method: DCI was defined as clinical deterioration due to impaired CBF. Growth curve analysis was used to examine temporal profiles of CPP change. Logistic regression was utilized to examine the association between DCI and percentages of CPP values >110, >100, 100 or >110 mmHg, the odds of DCI increased by 1.21 and 1.43, respectively. For every 10 mmHg increase in CPP, the odds of DCI increased by 2.78 (95%CI 2.00-3.87). High CPP was associated with earlier onset of DCI (p<.001). DCI did not mediate the relationship between HH and outcomes. Conclusions: When used prophylactically, induced hypertension contributes to higher CPP values. Based on the CPP trends/correlations observed, induced hypertension may not confer expected benefits in patients with aSAH. Findings raise concerns about safety of induced hypertension and the need for determining limits for hypertension, which current guidelines lack