Exploring student difficulties with observation location

Throughout introductory physics, students create and interpret free body diagrams in which multiple forces act on an object, typically at a single location (the object's center of mass). The situation increases in difficulty when multiple objects are involved, and further when electric and magnetic fields are present. In the latter, sources of the fields are often identified as a set of electric charges or current-carrying wires, and students are asked to determine the electric or magnetic field at a separate location defined as the observation location. Previous research suggests students struggle with accounting for how a measurement or calculation depends on the observation location. We present preliminary results from a studio-style, algebra-based, introductory electricity and magnetism course showing the prevalence of correct and incorrect responses to questions about observation location by analyzing student written work involving vector addition of fields

Training Needs of Secondary School Mathematics Teachers in the Yemen Republic

There is a need to conduct a research on identifying the training needs, which is considered one of the most essential components of a staff development programme. The present status of planning in-service training programmes and workshops for Mathematics teachers in Yemen lacks appropriate methodology and a systematic and comprehensive assessment of the trainees' needs. In addition, no attention has been paid to systematically identify in-service needs for Mathematics teachers of secondary schools in Yemen. The purpose of this study was to identify the training needs of secondary schools Mathematics teachers in two urban cities Sana'a and Amran. The study focused on training needs as perceived by secondary school Mathematics teachers, supervisors and school administrators and identified the teachers' current practices of Mathematics teaching in secondary schools.The sample of the study was a sample six hundred and twelve consisting of 389 Mathematics teachers, 34 supervisors and 189 school administrators using a stratified random sampling technique. To obtain the data two instruments were used: (i) the new questionnaire was designed by the researcher. The questionnaire classified in-service training needs (59 items) into five categories which include: implementing of Mathematics instruction, planning of Mathematics instruction, evaluation of students in Mathematics instruction, diagnosing students7 needs in Mathematics instruction and classroom management. (ii) The observation instrument was modified and developed by Shian Leou (1998) which consisted of 35 items covering four domains, teaching skills, material organization and presentation, management of the learning environment and teaching attitudes. The observation was conducted among 30 secondary school Mathematics teachers in the classes and a video camera was used to record the lessons. Data were analyzed using the SPSS computer programme. The means, standard deviations, frequency and percentages were computed for the criteria indicators and independent one-way ANOVA and t-test were computed to determine significant differences between the means of the groups. The findings of the study revqaled that all the training needs represented necessary needs for Mathematics teachers in secondary schools and the teacher's current practice of Mathematics teaching was generally weak. These findings indicated highest needs in implementing of Mathematics instruction, followed by planning of Mathematics instruction, evaluation of students in Mathematics instruction, diagnosing students' needs in Mathematics instruction and classroom management. The One-way ANOVA revealed that there are no significant differences in perceptions of training needs between teachers, supervisors and school administrators in all domains. As for the variable of experience, a significant difference was found in the domains of classroom management and evaluation of students in Mathematics instruction. The effect of the t-test showed that there is no significant difference between male and female teachers in all domains. However, a significant difference was found between a variable of with educational and without educational background in the domain of evaluation of students in Mathematics instruction. The results of this study were consistent with previous findings in other specialization studies; therefore, it is recommended that a future study should do a comparative study on the training needs among Mathematics teachers in secondary schools and primary schools. A future replication of this study with comparison with other countries is necessary

Agrometeorological forecasting

Agrometeorological forecasting covers all aspects of forecasting in agrometeorology. Therefore, the scope of agrometeorological forecasting very largely coincides with the scope of agrometeorology itself. All on-farm and regional agrometeorological planning implies some form of impact forecasting, at least implicitly, so that decision-support tools and forecasting tools largely overlap. In the current chapter, the focus is on crops, but attention is also be paid to sectors that are often neglected by the agrometeorologist, such as those occurring in plant and animal protection. In addition, the borders between meteorological forecasts for agriculture and agrometeorological forecasts are not always clear. Examples include the use of weather forecasts for farm operations such as spraying pesticides or deciding on trafficability in relation to adverse weather. Many forecast issues by various national institutions (weather, but also commodity prices or flood warnings) are vital to the farming community, but they do not constitute agrometeorological forecasts. (Modified From the introduction of the chapter: Scope of agrometeorological forecasting)JRC.H.4-Monitoring Agricultural Resource

Pyrolysis of biomass

Pyrolysis of biomass is considered to be a green technology since it has no impacts or emissions to the environment. Pyrolysis of biomass is the initial stage in the gasification process and is defined as the thermal decomposition of biomass into valuable products such as char, tar, and gas. In this study, a pyrolysis reactor was designed and constructed, and experimental tests were performed to study the pyrolysis products, especially the gas compositions. An extensive literature study has been carried out on the pyrolysis of biomass along with the effects of different operational conditions on the product yields. Further, computational particle fluid dynamic (CPFD) simulations were performed to study the composition of the synthesis gas obtained from the gasification of wood pellets

Adaptive intelligent tutoring for teaching modern standard Arabic

A thesis submitted to the University of Bedfordshire, in partial fulfilment of the requirements for the degree of Doctor of PhilosophyThe aim of this PhD thesis is to develop a framework for adaptive intelligent tutoring systems (ITS) in the domain of Modern Standard Arabic language. This framework will comprise of a new approach to using a fuzzy inference mechanism and generic rules in guiding the learning process. In addition, the framework will demonstrate another contribution in which the system can be adapted to be used in the teaching of different languages. A prototype system will be developed to demonstrate these features. This system is targeted at adult English-speaking casual learners with no pre-knowledge of the Arabic language. It will consist of two parts: an ITS for learners to use and a teachers‘ tool for configuring and customising the teaching rules and artificial intelligence components among other configuration operations. The system also provides a diverse teaching-strategies‘ environment based on multiple instructional strategies. This approach is based on general rules that provide means to a reconfigurable prediction. The ITS determines the learner‘s learning characteristics using multiple fuzzy inferences. It has a reconfigurable design that can be altered by the teacher at runtime via a teacher-interface. A framework for an independent domain (i.e. pluggable-domain) for foreign language tutoring systems is introduced in this research. This approach allows the system to adapt to the teaching of a different language with little changes required. Such a feature has the advantages of reducing the time and cost required for building intelligent language tutoring systems. To evaluate the proposed system, two experiments are conducted with two versions of the software: the ITS and a cut down version with no artificial intelligence components. The learners used the ITS had shown an increase in scores between the post-test and the pre-test with learning gain of 35% compared to 25% of the learners from the cut down version

Immune Response Modulation through Physical Activity: Mechanisms and Outcomes

This study explores the intricate relationship between physical activity and immune response modulation, utilizing secondary data to synthesize existing knowledge on the mechanisms and outcomes involved. Through comprehensive analysis of epidemiological studies, clinical trials, and meta-analyses, the investigation highlights how various forms of physical activity, ranging from moderate exercise to high-intensity training, influence immune function. Key findings illustrate that regular moderate exercise enhances immune surveillance, reduces inflammation, and improves vaccine efficacy, while excessive exercise may impair immune function and increase susceptibility to infections. The study elucidates the underlying mechanisms, including the mobilization of immune cells, cytokine production, and hormonal alterations, offering insights into how physical activity acts as a non-pharmacological strategy to bolster immune health. Additionally, the research underscores the significance of personalized exercise regimens tailored to individual health profiles to optimize immune outcomes. By consolidating current evidence, this study aims to inform public health policies and encourage the integration of physical activity into preventive healthcare strategies to enhance immune resilience across diverse populations

Factors determining crude oil price

Causes of oil price increase have been a subject of much interest and numerous studies given the importance of oil as the main source of energy of the world. In the last two decades, the price of crude oil has been fluctuating rapidly and at times drastically. But the causes of the rise in the price of crude oil still remained a controversy. Literature has two views. The first group argues that the changes in oil prices are due to supply and demand. The other claims that financial variables (speculation and future markets) play a big role in crude oil price changes. The objectives of this study to determine the main determinants of crude oil price changes by using the VECM model and examine the effect of the new variables in the oil market such as; days of forward supply and convenience yield on oil price changes. This study examines four main factors that affect crude oil prices which are; supply variables, demand variables, geopolitics and speculation. The results of this study indicate that oil prices in the last two decades especially after the crisis in 2008 are determined by fundamental variables which are total oil rigs, days of forward supply and convenience yield. Moreover, principal component analysis indicates that days of forward supply is the nearest factor in the PCA coordinate system which explains the changes in crude oil prices

Cloud Computing For Iraqi Ministry Of Finance

Cloud Computing, the long-held dream of computing as a utility, has the potential to transform a large part of the IT industry, making software even more attractive as a service and shaping the way IT hardware is designed and purchased. Developers with innovative ideas for new Internet services no longer require the large capital outlays in hardware to deploy their service or the human expense to operate it. They need not be concerned about over provisioning for a service whose popularity does not meet their predictions, thus wasting costly resources, or under provisioning for one that becomes wildly popular, thus missing potential customers and revenue. Moreover, companies with large batch-oriented tasks can get results as quickly as their programs can scale, since using 1000 servers for one hour costs no more than using one server for 1000 hours. This elasticity of resources, without paying a premium for large scale, is unprecedented in the history of IT. Cloud Computing refers to both the applications delivered as services over the Internet and the hardware and systems software in the datacenters that provide those services. The services themselves have long been referred to as Software as a Service (SaaS) [2]. The datacenter hardware and software is what we will call a Cloud. When a Cloud is made available in a pay-as-you-go manner to the general public, we call it a Public Cloud; the service being sold is Utility Computing. We use the term Private Cloud to refer to internal datacenters of a business or other organization, not made available to the general public. Thus, Cloud Computing is the sum of SaaS and Utility Computing, but does not include Private Clouds. People can be users or providers of SaaS, or users or providers of Utility Computing. We focus on SaaS Providers (Cloud Users) and Cloud Providers, which have received less attention than SaaS Users. From a hardware point of view, three aspects are new in Cloud Computing [3]

A 1.5-pproximation algorithms for activating 2 disjoint stst-paths

In the $Activation$ $k$ $Disjoint$ $st$-$Paths$ ($Activation$ $k$-$DP$) problem we are given a graph $G=(V,E)$ with activation costs $\{c_{uv}^u,c_{uv}^v\}$ for every edge $uv \in E$, a source-sink pair $s,t \in V$, and an integer $k$. The goal is to compute an edge set $F \subseteq E$ of $k$ internally node disjoint $st$-paths of minimum activation cost $\displaystyle \sum_{v \in V}\max_{uv \in E}c_{uv}^v$. The problem admits an easy $2$-approximation algorithm. Alqahtani and Erlebach [CIAC, pages 1-12, 2013] claimed that Activation 2-DP admits a $1.5$-approximation algorithm. Their proof has an error, and we will show that the approximation ratio of their algorithm is at least $2$. We will then give a different algorithm with approximation ratio $1.5$