Naresuan University Journal
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Using PBL with FILA Chart to Design Learning Activities on Fundamental Principle of Counting to Support Problem-Solving Skills
No full textThe key successful in mathematical problem solving is that students could employ problem-solving skills for performing in problem-solving process related to mathematical problems posed by instructors in a mathematics classroom. However, it is found that there are many students frustrated with using problem-solving skills in practice because thinking simultaneously with mathematics problems and procedures in solving them based on problem-solving skills seem to be abstract and very difficult for students. The purposes of this study are to develop learning activities using PBL with FILA chart as a scaffolding tool applied for supporting students to use problem-solving skills in performing with mathematics problems on Fundamental Principle of Counting step by step. To determine the effect of using learning activities using PBL with FILA chart on the levels of students’ problem solving skills, three subjective tests about subject matter on Fundamental Principle of Counting are administered as posttest to student. The rubric score is employed to determine the level of students’ problem solving skills through their performing in subjective tests. Data from rubric for evaluating student’ problem solving skills is analyzed using descriptive statistics to find frequency of students identifying particular student’ skill levels in problem solving for each of essential features of problem solving skills and to compute the mean skill levels in problem solving of students for each essential features. The results have verified the significant effects that learning activities using PBL with an effect FILA chart. Keywords: FILA Chart, Problem Based Learning, Problem Solving, Problem Solving Skills, Fundamental Principle of Counting
Effect of Aqua Blasting, Sandblasting and Laser Engraving on the Corrosion Resistance of Type 316 Stainless Steel
No full textThe goal of this paper is to advance our understanding about the influence of commercial surface finishing treatments on microstructure development and corrosion resistance of a type 316L stainless steel. Aqua blasting, sandblasting, and application of a laser barcode engraving treatment were investigated using Focus Ion Beam , X-ray phase analysis, X-ray residual stress measurements, and surface roughness measurements. All surface microstructures were then assessed with atmospheric corrosion tests at 50°C and 30% relative humidity. Aqua blasting resulted in compressive surface residual stresses of -500 to -600 MPa, with no evidence of strain-induced martensite. Sandblasting led to compressive surface residual stresses of -700 MPa, also with no evidence of strain-induced martensite. The samples subjected to laser engraving exhibited a recrystallized near-surface microstructure, with tensile surface residual stresses in the order of +500 MPa.Atmospheric corrosion tests were carried out using MgCl2 concentrations of 38-772 µg/cm2, with optical and laser confocal microscopy applied to quantify the development of corrosion products over time. The latter was correlated with the maximum depth of attack after exposure for 370 days of exposure. Atmospheric corrosion tests with deposition densities exceeding 38 µg/cm2 MgCl2 led to the formation of corrosion products within the first 24 hours of exposure, with the development of corrosion products following parabolic growth laws. It is further shown that higher deposition densities led to fewer localised corrosion sites, but with larger dimensions in size. Laser engraving resulted in a higher number corrosion sites compared to the aqua blasted surfaces, with MgCl2 deposited over the interface between both finishin
Evaluating the potential of process sites for waste heat recovery
No full textAs a result of depleting reserves of fossil fuels, conventional energy sources are becoming less available. In spite of this, energy is still being wasted, especially in the form of heat. The energy efficiency of process sites (defined as useful energy output per unit of energy input) may be increased through waste heat utilisation, thereby resulting in primary energy savings. In this work, waste heat is defined and a methodology developed to identify the potential for waste heat recovery in process sites; considering the temperature and quantity of waste heat sources from the site processes and the site utility system (including fired heaters and, the cogeneration, cooling and refrigeration systems). The concept of the energy efficiency of a site is introduced – the fraction of the energy inputs that is converted into useful energy (heat or power or cooling) to support the methodology. Furthermore, simplified mathematical models of waste heat recovery technologies using heat as primary energy source, including organic Rankine cycles (using both pure and mixed organics as working fluids), absorption chillers and absorption heat pumps are developed to support the methodology. These models are applied to assess the potential for recovery of useful energy from waste heat. The methodology is illustrated for an existing process site using a case study of a petroleum refinery. The energy efficiency of the site increases by 10% as a result of waste heat recovery. If there is an infinite demand for recovered energy (i.e. all the recoverable waste heat sources are exploited), the site energy efficiency could increase by 33%. The methodology also shows that combining technologies into a system creates greater potential to exploit the available waste heat in process sites
Moral geographies of family: articulating, forming and transmitting moralities in everyday life
No full textThe family is often considered the foundation of moral learning in society, responsible for caring and parenting, and transmitting morals to children and young people, while a lack of moral guidance from family is associated with antisocial behaviour. Despite this deep moralizing of family life, very little is known about how morals are understood in the context of family, how family members form their moral outlooks, and how morals and difference are negotiated within everyday family practices. This paper addresses some of these burgeoning questions around the moral geographies of family. Drawing on two years of ethnographic research with six families in the UK, I consider normative assumptions about what morals mean to families, which parts of family life morals are drawn from, and how morals are transmitted by and within families. In the conclusion I outline my contributions to both established and emerging areas of geographical interest
Production Principles for a T 3D Woven Nodal Structure (T-3DWNS).
No full textThe integrated three-dimensional (3D) woven nodal structure (3DWNS) is regarded as one category of 3D textile structure, and it has potential applications for creating lightweight composite truss structures. The conventional weaving technology has been adapted for the manufacture of a variety of 3DWNS’s. This allows the production, in the woven fabric plane, of either a two dimensional (2D) flat solid form, or a 2D shaped woven preform. Once the woven 2D form is removed from the tensions of the loom enables the transition from 2D into a 3D woven structure (2D-to-3D). This paper introduces an innovative approach based on the conventional weaving principles for creating a fully integrated 3DWNS in a T-shape (T-3DWNS). This fabrication method provided the forming of a node point without distortion, whilst maintaining the circumference of the adjoining child strut to a main/parent strut. This eliminated the need for further joining processes to bond the truss structure together; providing a fully integrated and lighter textile truss structure for composites engineering. This paper defines the design parameters and range of specifications for the production of the T-3DWNS and introduces derivative configurations for future development
Expressions of student debt aversion and tolerance among academically able young people in low-participation English schools
No full textThe 2012 rise in student fees, from £3375 to £9000 per year, made England one of the costliest places to attend university in the world. Drawing on evidence from higher attaining young people attending low-participation schools, this paper renews established types of student debt aversion and tolerance, with sensitivity towards whether they reflect the (financial) ‘price’ of participation or the (cultural, social) ‘cost’ of participation. Findings point to a complex web of inter-related factors informing a decision-making process that is rational, but often lacking detailed knowledge of key variables, such as the range of bursaries and grants available and the terms of the loan repayment. The Ellsburg Paradox is invoked to explain the tendency of some young people to self-exclude, contrary to rational choice theory. For those without family support or precedent, participation is not greatly incentivised by assumed lifestyle and identity gains, and generous repayment concessions for low-earning graduates do not necessarily ease anxiety about debt. Data point to a heightened awareness of labour market alternatives and of continued disquiet, both academic and non-academic, about ‘fitting in’ at university. Naturally, higher fees demand a recalculation of return-on-investment estimates for all young people. However, the participation ‘bet’ of those from low-participation schools is framed in ways unacknowledged by (and sometimes discordant with) dominant public discourses
Termination of BIF deposition in the Paleoproterozoic: the Tongwane Formation, South Africa
No full textThe Tongwane Formation (~2.4 Ga) conformably overlies banded iron formations (BIF; Penge Iron Formation) on the Kaapvaal Craton, South Africa. As such, it provides a unique window into depositional processes and environmental conditions in the aftermath of major Archean-Paleoproterozoic BIF deposition, and on the eve of irreversible environmental oxygenation in the Great Oxidation Event (GOE, ~2.35 Ga). This study presents the first sedimentological and bulk-rock geochemical characterization of the Tongwane Formation to provide a sedimentological and stratigraphic framework for further studies of early Paleoproterozoic environments. The Tongwane Formation is 220m thick and consists from the base up of shales, siliceous mudstones with local BIF facies, interbedded mudstones and dolomites, and a massive dolomite unit at the top. Strata record the progressive shallowing of depositional environments from deep shelf (BIF) to a wave-swept carbonate ramp. Intervening slope environments record increased detrital sedimentary input in the form of shales and distal turbidites. The carbonate ramp had a distally steepened margin as documented by an important margin collapse breccia. Extension due to seismic forces and/or slope steepening caused progressive deformation of slope deposits, from slumping and fracturing through sedimentary boudinage, to brecciation, and mass wasting. Termination of BIF deposition could have been related to (a) shutdown of Fe-precipitating processes, (b) shutdown of the hydrothermal Fe source, (c) shallowing of environments to restrict BIF deposition to deeper parts of the basin, (d) masking of Fe deposition by increased detritus, or a combination of these. Although a partial or complete shutdown of the Fe source or of Fe precipitating processes cannot be excluded, the weight of evidence from the Tongwane Formation favors external factors such as relative sea level fall and Fe dilution by increased detrital input as the main drivers for the BIF-carbonate transition. All samples fall on a mixing curve between hydrothermal and detrital end members, and despite metamorphic overprint, a weak hydrothermal signature is observed up to below platform deposits. These results stress the importance of understanding sedimentary factors in studies of Archean-Paleoproterozoic environments
Proinflammatory genotype is associated with the frailty phenotype in the English Longitudinal Study of Ageing
No full textTreatment Barriers and Support for Male Ex-Armed Forces Personnel in Prison: Professional and Service User Perspectives
No full textEx-armed forces personnel represent a potentially vulnerable group within the prison population. To provide support to this group, we need to understand their needs and help-seeking behavior. A focus group with professionals and semi-structured interviews with service users explored perspectives of the treatment barriers faced by this group and their support needs. Data were analyzed using constant comparison methods, and four primary themes were identified. The findings suggest ex-armed forces personnel consider prison an opportunity to access support but find it difficult to ask for help. Staff having an awareness of military issues was thought to encourage help-seeking, but the variability of provision across prison establishments was considered a barrier. Resettlement was a prominent concern, and access to support when preparing for, and after, release was felt by all participants to be important. Implications for the provision of support in prison are discussed along with recommendations for practice