The aim of this study is to compare the effects of three methods: problem-based learning (PBL), PBL with lecture method, and conventional teaching on the understanding of thermodynamics, group work and self-directed learning skills among physics undergraduates. The actual sample size comprises of 122 students, who were selected randomly from the Physics Department, College of Education in Iraq, for academic year 2011-2012. In this study, the pre and posttest were done and the instruments were administered to the students for data collection. Inferential statistics were employed to analyze data. The independent variables were the PBL, the PBL with lecture method, and the conventional teaching. Dependent variables of statistical analysis were posttest scores on the understanding of thermodynamics, group work skills, and self-directed learning skills. Covariates of statistical analysis were pretest scores of the understanding of thermodynamics, group work skills, and self-directed learning skills. The data were analyzed using statistical package social sciences (SPSS) version 19. Overall, the statistical results rejected all null hypotheses of this study. Thus, the use of PBL with lecture method enhances the understanding of thermodynamics better than using the PBL alone or using conventional teaching method. Using the PBL without or with lecture method promotes the skills of group work, and self-directed learning better than using the conventional teaching, among physics undergraduate.
In the mist of developments in the course of scientific research in general and humanities in particular and the accompanying changes in the visions and policies inspired by the need for these sciences to follow the qualitative methods in dealing with many of the topics or problems that require for their solution to obtain qualitative information which can be provided by resorting to quantitative research. Therefore, a new trend has emerged in many public relations› researchers who believe that qualitative research methods should be used by establishing scientific foundations and methodological classification based on the use of these methods and determining the nature of the subjects applied in them to reach results that are character
... Show MoreThis paper aims to study the effect of circular Y-shaped fin arrangement to improve the low thermal response rates of a double-tube heat exchanger containing Paraffin phase change material (PCM). ANSYS software is employed to perform the computational fluid dynamic (CFD) simulations of the heat exchanger, including fluid flow, heat transfer, and the phase change process. The optimum state of the fin configuration is derived through sensitivity analysis by evaluating the geometrical parameters of the Y-shaped fin. For the same height of the fins (10 mm), the solidification time is reduced by almost 22%, and the discharging rate is enhanced by almost 26% using Y-shaped fins compared with the straight fins. The results demonstrate that the sol
... Show MoreThe litholog of Nahr Umr Formation was evaluated using the Acoustic Impedance (AI), Vp/Vs ratio cross plot colored by petrophysical properties (Vsh, PHIT, PHIE, and Sw) in Am-6-Am-10 wells. Bulk density is an important physical property that reflects matrix density and fluid density that exist in rocks pores. It is used as the main parameters to estimate physical characteristics (porosity, water saturation, shale volume, and others). AI was calculated using RHOB and VP logs. Shear velocity was calculated using Greenberg Castagna equations used for estimating the Vp/Vs ratio and the result Showed that the Nahr Umr Formation is composed of two main lithological units. The upper unit (depth 3540m -3672m) is composed of limestone (li
... Show MoreThe quality of groundwater is just as important as its quantity. The kinds and concentration of salts in groundwater depend on the environment, movement, and the source of the groundwater. During the field work, 20 samples have been collected from water wells from Al-Salman basin for two seasons represent wet and dry seasons in November 2017 and April 2018. After water well samples have been analyzed the Electrical conductivity values range from (2260 to 5500) μS/cm for dry season and range from (2540 to 5630) μS/cm for wet season, the Total dissolved solids values range from (1289 to 3582) ppm for dry season and range from (1710 to 3960) ppm for wet season, and pH values range from (7.11 to 7.3) for dry and wet seasons. The Hydroc
... Show MoreFourty three isolates ( 20.7%) characterized as Staphylococcus aureus , were isolated from 207 different clinical sources (blood , nose, , wound , urine , vaginal, ear and eye) in different percentages (30.23, 18.60, 16.28, 13.95, 15.15, 6.96 and 2.33 %), respectively. The staphyloxanthin (STX) production of S. aureus isolate was estimated 72.1% .The optimal conditions for pigment production by S. aureus AE36 , were detected and was noticed that the milk agar medium revealed the highest production of pigment which was estimated to be 165.21unit/cell, at pH 8 for 72 hr at 370C. The Staphyloxanthin pigment was extracted using methanol and was purified partially by organic solvents and Thin Layer Chromatography (TLC). The results revealed t
... Show MoreMany economic entities working in multiple industrial fields suffer fromlow techniques in using modern administrative means in their works. The mostused tool in measuring required procedures is to adopt and use quality costs. inspite of complications and bronchial of operations in construction projects, Theresearcher was able to find a structure to quality costs according to traditionclassification (prevention, Appraisal, failure) which enables the calculation ofthese costs and then analyze results and setting standards which can beimplemented in evaluating strategic performance for targeted project. and theforge research in theoretical fly to quality and costs concerning it inconstruction section , as well as strategically performance a
... Show MoreObjective(s): The study aims to evaluate the information of the elderly about personal hygiene , and to find out the relationship between residents of geriatric-care homes knowledge and their demographic characteristics .
Methodology: A quasi-experimental design study is conducted at geriatric home in Al Cyelakh Geriatric Care Home. The study was started at between November 20, 2021, and March 1, 2023. randomly sample of (30) elderly in geriatric home were studied . Data were collected throughout the utilization of the adopted questionnaire and interview technique. The questionnaire was consists of (40) items related to concerned personal hygiene geriatrics persons, t
... Show MoreAn electrical survey was carried out by using 2D imaging technique at (15)
station. The study area is located southern Al-Shihaby area, south-east of Wasit
governorate, Eastern Iraq. The numbers of the employed electrodes were (120) and
the (a) spacing equal to (10m), and the total length of survey line is (1200m). The
inverse models of 2D imaging showed one Quaternary aquifer located in the
Quaternary deposits which comprises in alluvial fan and wind deposits of
(Pleistocene – Holocene) ages. Layers of aquifer consist of gravel and sand with
little silt. Low resistivity values reflected the presence of clay layers, and increasing
salinity of water gradually with the depth. The aquifer occurs at minimum depth
Abstract
The study of oxygen mass transfer was conducted in a laboratory scale 5 liter stirred bioreactor equipped with one Rushton turbine impeller. The effects of superficial gas velocity, impeller speed, power input and liquid viscosity on the oxygen mass transfer were considered. Air/ water and air/CMC systems were used as a liquid media for this study. The concentration of CMC was ranging from 0.5 to 3 w/v. The experimental results show that volumetric oxygen mass transfer coefficient increases with the increase in the superficial gas velocity and impeller speed and decreases with increasing liquid viscosity. The experimental results of kla were correlated with a mathematical correlation des
... Show MoreGroundwater is considered as one of the most important sources of fresh-water, on which many regions around the world depend, especially in semi-arid and arid regions. Protecting and maintaining groundwater is a difficult process, but it is very important to maintain an important source of water. The current study aims to assess the susceptibility of groundwater to pollution using the DRASTIC model along with the GIS environments and its tool boxes. A vulnerability map was created by relying on data collected from 55 wells surveyed by the researchers as well as archived records from governmental institutions and some international organizations. The results indicate that the region falls into three vulnerability functional zones , namely
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