Hala Laz - Academia.edu (original) (raw)

Papers by Hala Laz

 Abstract— This paper demonstrates that the constructivist learning model in the teaching of mat... more  Abstract— This paper demonstrates that the constructivist learning model in the teaching of mathematics has a great impact in the acquisition of concepts , constructivist theory of theories that are based on building knowledge of learners , cares structural model including the learners schemes conceptual , is also interested to apply the active and effective in new situations he cares what any after learning and transfer of knowledge and experience to take advantage of them in the construction of experiences associated with new positions .The study was applied to samples of students in the preparatory year at the University of Tabuk and the two divisions to choose at random to represent one of the experimental group and the other control group. The result was that there were statistically significant differences between the mean scores of students of experimental and control groups in the post application to test the statistical concepts for the benefit of students of the experimental group.

The paper is studying the renewal process. There are many fields in which it's used for examp... more The paper is studying the renewal process. There are many fields in which it's used for example: the renewable energy (solar energy, wind energy), maintenance and replacement decision models, queuing system and other field in electronics. In this study our objective is to find the probability density function related to a renewal at a given time. Also to drive the renewal equation, how to find the current lifetime and residual life time. We obtain that as expected value of a renewal process which is the renewal function or mean-value function of the renewal process. Also we use the renewal equation and renewal reward processes in the applications. The solutions of these applications show a real answers due to reality conditions within a given accuracy.

The issue of air quality conditions and atmospheric pollution in the Arab Region has been address... more The issue of air quality conditions and atmospheric pollution in the Arab Region has been addressed through consideration of the energy production and energy consumption pattern. Global, regional and local sources of air pollution in the study have been considered. Emission scenarios of many Arab countries of the region have been outlined. It has been realized that air pollution constitutes one of the major sources of loss on GNP of many Arab countries in the region due to weak institutional capabilities for air pollution management and control. Major types of air pollution sources in the region such as greenhouse gas emissions and other gases from various industries are considered. Local sources of air pollution are found due to urban growth, transportation systems, industrialization and lack of awareness and shortage of institutional capabilities all contributed to the relatively low air quality and weak control in the Arab Region. The purpose of this paper is to review all available literature on the issue of air pollution in Arab countries due to combustion of fossil fuel coming from mobile sources and petroleum gas flaring in order to present the dire situation of the air quality in Arab countries. The report is organized based on certain factors which make the transport sector , power plants and associated gas flaring are significant polluters of the air in the Arab region. We present a brief introduction to the composition of the transport sector in most of Arab countries and the forms of emissions resulting from it, then the report continues with the explanation of the major impacts that old-aged machines like automobiles, old petroleum production technology and old electrical energy plants technology have in terms of causing air pollution in these countries and thus; making them very inefficient and also very harmful towards the environment in most of Arab countries. In this paper also we have used the statistical data during the years 2005 -2008 in terms of air pollution in most of Arab countries compared with each other. We have taken for study six largest air polluting agents that are accepted by international organizations such as NAAQS (Air Quality Standards National Environmental), EPA (Environmental Protection Agency) of U.S. and sometimes (USEPA), which today are used widely worldwide, and the WHO. The six pollutants are: CO-Carbon Mono-oxide, Ozone O3, at the lower atmospheric layers, Pb-lead, SO2, sulfur dioxide, PM10 (and in some cases PM2.5) -particles of dust, and NO2-nitrogen oxide. In the present study is analyzed also the ways of reducing the environmental pollution by emissions of gases that cause mobile engines in urban areas. In the study is given changes in emissions of gases depending on the improvement of mobile construction, according to years of production, in accordance with the requirements established by the legislation of EU countries and mobile manufactures. The level of emissions from automobile engines in the city of Tabuk (Saudi-Arabia), for all types of engines is taken as examples to be measured and examined according to the years of production. It's found that changing the structure vehicle inserted in use for automobiles of production after 1996, their pollution level decreases twice. Also in the study is analyzed the possibility of modifying the urban intersections with additional lanes before crucifixion to reduce the residence time of vehicles in traffic and reduce environmental pollution to two times. Furthermore, we analyze the issue of the low quality fuel being used in some of these countries which increases the emissions of harmful waste gases. Moreover, this paper also presents the issue(s) of the lack of legal control which further enables mobile sources to circulate without catalytic converters.

This paper will examine in detail the conditions of correctly inflated tire pressure that gives a... more This paper will examine in detail the conditions of correctly inflated tire pressure that gives appropriate support from the contained air pressure to provide an even distribution of load across the footprint and help stabilize the tire's structure which has a significant impact on tire wear, rolling resistance, durability and allows drivers to feel acceptable vehicle comfort, and adequate performance. Tire industry load and inflation standards are in a constant state of change and all tires manufacturers continually updates their product information to reflect these changes. Therefore the printed information's may not reflect the latest load and inflation standards, so tires users will be in need of continuous following for information updating and this is one of the main problem for the most tire dealer. In this paper we have taken into consideration all factors and the condition of tire work that have direct effect on tires performance, stability and safety. Also the paper is presenting all technical procedures to guarantee better performance, stability, safety and long duration. Finally, the paper will introduce the risks faced by the use of improper pressure inflation and worn tires.

This paper will examine in detail the conditions of correctly inflated tire pressure that gives a... more This paper will examine in detail the conditions of correctly inflated tire pressure that gives appropriate support from the contained air pressure to provide an even distribution of load across the footprint and help stabilize the tire's structure which has a significant impact on tire wear, rolling resistance, durability and allows drivers to feel acceptable vehicle comfort, and adequate performance. Tire industry load and inflation standards are in a constant state of change and all tires manufacturers continually updates their product information to reflect these changes. Therefore the printed information’s may not reflect the latest load and inflation standards, so tires users will be in need of continuous following for information updating and this is one of the main problem for the most tire dealer. In this paper we have taken into consideration all factors and the condition of tire work that have direct effect on tires performance, stability and safety. Also the paper i...

The paper is trying to give information about motor lubricant oil its grades according to relativ... more The paper is trying to give information about motor lubricant oil its grades according to relatively international standard. The paper suggested that due to poor oil personnel experience in Sudan lubricant oil choosing and change shows less effectiveness. The objectives of this study are to give the condition of maintaining correct time for the motor oil changing and the suitable oil type that helps to optimize lubricant cost and performance for motor engine. For that the process of fixing motor oil type and changing duration is done by using a mathematical model that has a direct relation to economical concepts and machine technical condition. The study used a data of an experimental work done by Honda International Company for an engine oil to fix its duration interval. Also the paper shows that the machine lubricant industry specifications, its general grades and machine manufacturer directions are very confusable. They are in a constant state of change; therefore the printed information's may not reflect the latest specifications. So from the side of motor oil users and engine manufacturer they are asked to update continuously their information. The paper is suggested that an international effort should be done extremely in the field of lubricant oil quality control and to give lubricant oil personnel considerable training to insure suitable oil and safety timing for machine oil changing. No doubt this leads to lengthen machine time life duration, helps to lessen machine wearing, car failure, environmental risk and to minimize maintenance cost. Paper is suggested that all new car engines should be provided with the oil life monitoring systems that notify the driver when an oil change is required.

This paper gives a general view about the existing situation of tire recycling disposal and tire ... more This paper gives a general view about the existing situation of tire recycling disposal and tire maintenance activities in many parts of the world and in Middle East particularly. Saudi-Arabia as an important country in particular is taken as an example with respect to international concepts in ecology conservation. It concentrates on the auto repair activities with regard to the generated waste tires; its volume, amount, and the general methods of their processing and disposal in Saudi-Arabia as the highest number of automobile fleet among the whole Middle East countries. It gives a rough estimation of waste tires as one of the problematic of automobile waste element that accumulated in auto repair workshops and scattered around areas in Saudi Arabia nowadays and in the nearest coming years to show the hazardous situation environmentally. The latest standard methods of waste tire processing, maintenance and recycling by using special latest technologies. it attempts to give a gener...

The paper is trying to give an enlightening about pneumatic tires services in Sudan especially an... more The paper is trying to give an enlightening about pneumatic tires services in Sudan especially and in the most developing countries. The paper suggested that the tire now a day’s shows low time life duration and less safety. It also gives the condition of maintaining correct cold tire inflation pressure rate for different sizes that helps optimize tire performance and fuel economy with respect to tire load capacity and tire size. The paper also recognizes that correctly inflated tires receive appropriate support from the contained air pressure, this provide an even distribution of load across the footprint and help stabilize the tire's structure which has a significant impact on tire wear, rolling resistance, durability and allows drivers to experience tire comfort, and performance. Also the paper shows that the tire fitter men have a relatively low scientific base to know how to deal with providing tires a proper cold inflation pressure rate. The nominated industry tire load an...

This paper will examine in detail the conditions of correctly inflated tire pressure that gives a... more This paper will examine in detail the conditions of correctly inflated tire pressure that gives appropriate support from the contained air pressure to provide an even distribution of load across the footprint and help stabilize the tire's structure which has a significant impact on tire wear, rolling resistance, durability and allows drivers to feel acceptable vehicle comfort, and adequate performance. Tire industry load and inflation standards are in a constant state of change and all tires manufacturers continually updates their product information to reflect these changes. Therefore the printed information’s may not reflect the latest load and inflation standards, so tires users will be in need of continuous following for information updating and this is one of the main problem for the most tire dealer. In this paper we have taken into consideration all factors and the condition of tire work that have direct effect on tires performance, stability and safety. Also the paper is...

This paper attempts to give a general view about the existing auto repair workshop activities in ... more This paper attempts to give a general view about the existing auto repair workshop activities in Khartoum Industrial Area with respect to clean production concepts. It concentrates on the auto pair activities with regard to the generated wastes; its volume, amount, and the general methods of their processing and disposal of these wastes in Khartoum industrial area. The paper gives a rough estimation of some waste elements in auto repair workshop, to show the hazardous situation environmentally. The paper gives the latest standard methods of waste processing and recycling of auto repair workshop by using special latest technologies. Also the paper suggests that the future is very risky unless the authorized persons are aware of what is going on auto repair workshops, and to plan for guarantee cleaner production by suitable scientific means. It also suggested establishment of special unit dealing with encouraging works, studies, and researches for treatment and recycling of out repair...

This paper will examine in detail the conditions of correctly inflated tire pressure that gives a... more This paper will examine in detail the conditions of correctly inflated tire pressure that gives appropriate support from the contained air pressure to provide an even distribution of load across the footprint and help stabilize the tire's structure which has a significant impact on tire wear, rolling resistance, durability and allows drivers to feel acceptable vehicle comfort, and adequate performance. Tire industry load and inflation standards are in a constant state of change and all tires manufacturers continually updates their product information to reflect these changes. Therefore the printed information’s may not reflect the latest load and inflation standards, so tires users will be in need of continuous following for information updating and this is one of the main problem for the most tire dealer. In this paper we have taken into consideration all factors and the condition of tire work that have direct effect on tires performance, stability and safety. Also the paper i...

This paper will examine in detail the conditions of correctly inflated tire pressure that gives a... more This paper will examine in detail the conditions of correctly inflated tire pressure that gives appropriate support from the contained air pressure to provide an even distribution of load across the footprint and help stabilize the tire's structure which has a significant impact on tire wear, rolling resistance, durability and allows drivers to feel acceptable vehicle comfort, and adequate performance. Tire industry load and inflation standards are in a constant state of change and all tires manufacturers continually updates their product information to reflect these changes. Therefore the printed information’s may not reflect the latest load and inflation standards, so tires users will be in need of continuous following for information updating and this is one of the main problem for the most tire dealer. In this paper we have taken into consideration all factors and the condition of tire work that have direct effect on tires performance, stability and safety. Also the paper is...