The Fact of the Energy

This work deals with the Theoretical Physics. The fact of the energy was and still a complex problem in front of the scientists, so they could not reach to a definition  describes it. Knowing that the energy concept is a basic concept in the physics,  it can be said that “to introduce a solution for the problem of the energy fact may form a crucial point of change in the physics science life cycle. From here, this work takes its importance; this work comes to introduce a "definitive" solution for the disagreement about the fact of the energy concept. And reaching to this "definitive solution", the methodology used  in the analysis of the problem was the "logic science", which can reveal the mental oppositions that cause the ambiguity of the energy concept. Homogenizing with the purpose of the research and the neediness of the objectiveness, the research have gone through the following points and its corresponding processes: How did the energy concept appear and develop historically? To answer this question a scientific investigation established to introduce facts about the history of the energy concept refer to more than thousand years ago. How is the energy concept developed philosophically, i.e. how is it concluded from the experimental observations? To answer this question a “suitable” set of experimental observations was selected and treated by the logic science methods reaching to the energy concept trying to simulate how the past scientists developed it philosophically. Is the energy concept a fact? Finally, based on the facts introduced in the above points and other collected information, the fact of the energy concept discussed and analyzed using “the logical argument” methods, which produce undoubted judgments. Keywords: The Energy Concept, The Logic Science, Energy Fact

Forest Biomass and Land Cover Change Assessment of the Margalla Hills National Park in Pakistan Using a Remote Sensing Based Approach

Climate change is one of the greatest threats recently, of which the developing countries are facing most of the brunt. In the fight against climate change, forests can play an important role, since they hold a substantial amount of terrestrial carbon and can therefore affect the global carbon cycle. Forests are also an essential source of livelihood for a remarkably high proportion of people worldwide and a harbor for rich global biodiversity. Forests are however facing high deforestation rates. Deforestation is regarded as the most widespread process of land cover change (LCC), which is the conversion of one land cover type to the other land cover type. Most of this deforestation occurs in developing countries. Agricultural expansion has been reported as the most significant widespread driver of deforestation in Asia, Africa, and Latin America. This deforestation is altering the balance of forest carbon stocks and threatening biodiversity. Pakistan is also a low forest cover country and faces high deforestation rates at the same time, due to the high reliance of local communities on forests. Moreover, it is also the most adversely affected by climate change. Agricultural expansion and population growth have been regarded as the most common drivers of deforestation in Pakistan. Financial incentives such as ‘Reducing Emissions from Deforestation and Forest Degradation, and the Role of Conservation of Forest Carbon, Sustainable Management of Forests and Enhancement of Forest Carbon Stocks’ (REDD+) offer hope for developing countries for not only halting deforestation but also alleviating poverty. However, such initiatives require the estimation of biomass and carbon stocks of the forest ecosystems. Therefore, it becomes necessary that the biomass and carbon potentials of the forests are explored, as well as the LCCs are investigated for identifying the deforestation and forest degradation hit areas. Based on the aforementioned, the following research objectives/sub-objectives were investigated in the MHNP, which is adjoined with the capital city of Pakistan, Islamabad; A) Forest Biomass and Carbon Stock Assessment of Margalla Hills National Park (MHNP) A.1) Aboveground Biomass (AGB) and Aboveground Carbon (AGC) assessment of the Subtropical Chir Pine Forest (SCPF) and Subtropical Broadleaved Evergreen Forest (SBEF) using Field Inventorying Techniques A.2) Exploring linear regression relationship between Sentinel-1 (S1) and Sentinel-2 (S2) satellite data with the AGB of SCPF and SBEF A.3) AGB estimation combining remote sensing and machine learning approach B) LC Classification and Land Cover Change Detection (LCCD) of MHNP for the time-period between 1999 and 2019 B.1) LC Classification for the years 1999, 2009 and 2019 using Machine Learning Algorithm B.2) LCCD of MHNP between 1999 to 2019

Simulation of Generation Process for Asymmetric Involute Gear Tooth Shape with and without Profile Correction

In order to achieve any design study on a gear tooth or to carry out any type of analysis on a complete gear drive, the first step is the representation of the actual form of this tooth under consideration. In this work, a mathematical simulation of generation process for the symmetric involute gear teeth shapes based on the principle of the gear shaping process with a rack-shaped cutter has been developed to take into account the effect of asymmetric tooth profiles and the use of profile correction on each side of tooth with different design parameters for each side of tooth. As a result of this work, a computer program based on this mathematical simulation has been built to represent graphically step-by-step the actual form of symmetric and asymmetric gear teeth shapes with and without profile correction for different gear design parameters. Keywords: Involute Gear Teeth, Symmetric, Asymmetric, Profile Correction, Mathematical Simulation, Generation Process

Design for metal fused filament fabrication (DfMF3) of Ti-6Al-4V alloy.

Additive manufacturing (AM) offers unmatchable freedom of design with the ability to manufacture parts from a wide range of materials. The technology of producing three-dimensional parts by adding material layer-by-layer has become relevant in several areas for numerous industries not only for building visual and functional prototypes but also for small and medium series production. Among others, while metal AM technologies have been established as production method, their adoption has been limited by expensive equipment, anisotropy in part properties and safety concerns related to working with loose reactive metal powder. To address this challenge, the dissertation aims at developing the fundamental understanding required to print metal parts with bound metal powder filaments using an extrusion-based AM process, known as metal fused filament fabrication (MF3). MF3 of Ti-6Al-4V has been investigated, owing to significant interest in the material from aerospace and medical industries on account of their high strength-to-weight ratio, excellent corrosion resistance and biocompatibility. To investigate the material-geometry-process interrelationship in MF3 printing, the current work looks into the process modeling and simulation, the influence of material composition and resulting characteristics on printed part properties, effects of printing parameters and slicing strategies on part quality, and part design considerations for printability. The outcome of the work is expected to provide the basis of design for MF3 (DfMF3) that is essential to unlocking the full potential of additive manufacturing. Moreover, the layer-by-layer extrusion-based printing with the highly filled material involves several challenges associated with printability, distortion and dimensional variations, residual stresses, porosity, and complexity in dealing with support structures. Currently, a high dependency on experimental trial-and-error methods to address these challenges limits the scope and efficiency of investigations. Hence, the current work presents a framework of design for MF3 and evaluates a thermo-mechanical model for finite element simulation of the MF3 printing process for virtual analyses. The capability to estimate these outcomes allows optimization of the material composition, part design, and process parameters before getting on to the physical process, reducing time and cost. The quantitative influence of material properties on MF3 printed part quality in terms of part deformation and dimensional variations was estimated using the simulation platform and results were corroborated by experiments. Also, a systematic procedure for sensitivity analysis has been presented that identified the most significant input parameters in MF3 from the material, geometry and process variables, and their relative influence on the print process outcome. Moreover, feasible geometry and process window were identified for supportless printing of Ti-6Al-4V lattice structures using the MF3 process, and an analytical approach has been presented to estimate the extrudate deflection at the unsupported overhangs in lattice structures. Finally, the design and fabrication of Ti-6Al-4V maxillofacial implants using MF3 technology are reported for the first time confirming the feasibility to manufacture patient-specific implants by MF3. The outcome of the work is an enhanced understanding of material-geometry-process interrelationships in MF3 governing DfMF3 that will enable effective design and manufacturing

Analytical Solution of Bending Stress Equation for Symmetric and Asymmetric Involute Gear Teeth Shapes with and without Profile Correction

In this work, a developed analytical method based on a previous trial graphical method has been introduced to find the solution of bending stress equation for symmetric and asymmetric involute gear teeth shapes with and without profile correction and for different gear design parameters. In order to achieve this analytical solution, certain geometrical properties for gear tooth shape of tooth loading angle,  tooth critical section thickness, the load height from this section and Lewis form factor which are imperative to formulate the final form of the tooth bending stress equation must be determined analytically step-by-step. As a result of this work, the trial graphical method has been avoided by establishing a simple analytical expression which can be easily solved and it gives a higher accuracy and requires a shorter time. Keywords: Gear, Involute Teeth, Symmetric, Asymmetric, Profile Correction, Critical Section Thickness, Lewis Form Factor, Bending Stress Equation, Analytical Solution

Studies on the Measurement of Extractable and Mineralizable Nitrogen in Soil

The different potassium salts which are used for the extraction of inorganic nitrogen from soils contain variable and often high amounts of ammonium and nitrate nitrogen which could introduce an error in the analysis of low levels of soil inorganic nitrogen. The potassium salt solutions can be purified of ammonium nitrogen by increasing the pH to 11.0 with a solution of potassium hydroxide and then boiling and stirring for 15 minutes. The pH is then readjusted to pH 5.5 - 6.0 with a dilute acid. There is no simple method for the removal of nitrate nitrogen and therefore, it is suggested that a batch number with low nitrate nitrogen content be used for the extraction of soil. Different grades and batches of filter papers also contain variable amounts of ammonium and nitrate nitrogen which needs removing before use for the filtration of soil extracts. Ammonium and nitrate nitrogen can be removed from the filter papers by washing with 50 cm of 0.5 M potassium sulphate in 2 lots each of 25 cm3 , then rinsing twice with deionised water and drying for 4 hours at 7

Tunable and Growing Network Generation Model with Community Structures

Recent years have seen a growing interest in the modeling and simulation of social networks to understand several social phenomena. Two important classes of networks, small world and scale free networks have gained a lot of research interest. Another important characteristic of social networks is the presence of community structures. Many social processes such as information diffusion and disease epidemics depend on the presence of community structures making it an important property for network generation models to be incorporated. In this paper, we present a tunable and growing network generation model with small world and scale free properties as well as the presence of community structures. The major contribution of this model is that the communities thus created satisfy three important structural properties: connectivity within each community follows power-law, communities have high clustering coefficient and hierarchical community structures are present in the networks generated using the proposed model. Furthermore, the model is highly robust and capable of producing networks with a number of different topological characteristics varying clustering coefficient and inter-cluster edges. Our simulation results show that the model produces small world and scale free networks along with the presence of communities depicting real world societies and social networks.Comment: Social Computing and Its Applications, SCA 13, Karlsruhe : Germany (2013

Corporate Governance Mechanisms and Web-Based Investor Relations Activities: an Empirical Examination on Companies Listed in Abu Dhabi Stock Exchange

This study seeks to examine the relationship between Corporate Governance mechanisms and corporate web-based investor relations reporting practices of companies listed in Abu Dhabi Stock Exchange (ADX). The study draws a sample of 56 companies listed in ADX and conducted a content analysis on their websites to assess the level to which investor relations information are disclosed. Results of the content analysis showed that all companies included in the sample have a corporate websites and more than 50% disclose information related to investor relations. A multivariate regression analysis was conducted to find the relationship between 4 independent variables reflecting corporate governance mechanisms (Government ownership, Institutional ownership, Board independence, and Audit committee financial expertise) and Web-based investor relations disclosures. The results showed a significant positive relationship between Ownership structure (Government and Institutional) and Audit committee financial expertise and the degree to which companies disclose IR information on their websites. This indicates that strong corporate governance mechanisms are influencing and motivating companies to enhance and improve their disclosure activities by using a new medium (i.e. the internet) and therefore increasing the transparency and information availability to the stock market participants in emerging economies such as the UAE. Keywords: Corporate Governance, Investor Relations, Internet Financial Reporting, Voluntary Disclosure

The Impact of Corporate Governance on Firm Performance: Evidence from the UAE

This study seeks to examine the relationship between corporate governance and firm performance of companies listed in Abu Dhabi stock exchange. It is argued in this paper that strong corporate governance mechanisms are expected to have a positive impact on performance measures. The dataset is drawn from the Abu Dhabi exchange Shareholding Company’s guide for years 2007-2011.The study uses pooled regression analysis on 281 firm/year observations.In this regard, two measures of firm performance are used; Tobin’s Q score and Return on Assets (ROA), on the other hand independent variables include institutional ownership, governmental ownership, board size, and audit quality. The study controls for the relationship between the dependent and independent variables by including firm size, debt ratio, dividend yield, and age as control variables. Results showed significant positive impact of corporate governance measures on firm performance (except for Audit quality). Results obtained inthis research paper provide further evidence on the importance of corporate governance mechanisms on stock market participants’ valuation of listed companies. In addition, it makes us understand to some extent the attitudes of shareholders toward good corporate governance practices.The importance of this research paper stems from the fact that it is conducted in an emerging economy which has recently adopted a corporate governance code. In this regard, the UAE has put into action the new corporate governance code on 2007 and made it mandatory on all listed companies as on 2010, the current study focus on this period. As far as the current researcher is aware of, prior studies conducted in the UAE context were cross-sectional in nature and conducted before the implementation of the new code. Key words: Corporate Governance, Firm Performance, Ownership Structure, Emerging Markets

An investigation of the big-fish-little-pond effect (BFLPE) on academic self-concept and the social comparison types and standards among boys and girls in single-sex and co-educational schools in Jordan

This is an embedded mixed methods research study aimed at examining the associations of gender and schooling type with the Big Fish Little Pond Effect (BFLPE) in four school subjects: Arabic, English, Science and Math in the context of Jordan. The BFLPE hypothesizes that academic self-concept is positively affected by individual academic ability but negatively affected by the average ability of a class or school. Students’ ability was measured by using an ability test from PISA 2000 (Programme for international student assessment). Students’ academic self-concepts were measured by the academic self-description questionnaire II (ASDQII). The types of social comparison made in the classroom were investigated using semi-structured interviews. The systematic multi-stage cluster sampling was used in selecting 269 tenth grade male and female students from single-sex and co-educational schools in the northern regions in Jordan. 8 male and female students were randomly selected to take part in face-to-face interviews. The results showed that male and female students in single-sex and co-educational schools in Jordan suffered the BFLPE. A student’s own ability has a positive effect on their academic self-concept, but the average ability of a school is evident in having a negative effect on students’ academic self-concept in the four subjects. Gender has no influence on the academic self-concept. The type of school a student attends has a substantial influence on academic self-concept. Students who attend co-educational schools suffered a larger BFLPE than their peers in single-sex schools. The interaction between gender and school type was not significant in any of the four subjects’ self-concept. The findings from the interviews evidenced the downward and upward comparisons. The effect of downward comparisons on academic self-concept was positive; whereas, the effect of upward comparisons on academic self-concept was negative. The findings from the interviews also showed different social comparison standards that students used to establish their academic self-concepts such school grades, the participation in the class, homework, and teachers’ and parents’ comments