Search results for: performances of duties

Authors: Bouzaki Mohammed Moustafa, Benyoucef Boumediene, Benouaz Tayeb, Benhamou Amina

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The ambient temperature and the defects density in the Hetero-junction with Intrinsic Thin layers solar cells (HIT) strongly influence their performances. In first part, we presented the bands diagram on the front/back simulated solar cell based on a-Si: H / c-Si (p)/a-Si:h. In another part, we modeled the following layers structure: ZnO/a-Si:H(n)/a-Si:H(i)/c-Si(p)/a-Si:H(p)/Ag where we studied the effect of the ambient temperature and the defects density in the gap of the crystalline silicon layer on the performance of the heterojunction solar cell with intrinsic layer (HIT).

Keywords: heterojunction solar cell, solar cell performance, bands diagram, ambient temperature, defect density

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Authors: Mahdi Kazemi

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Today's performances on Piano Forte or Fortepiano are cheerful, musical, expressive, and at the same time informative. AlterMuskie is an exciting and richly drawn magazine that is unmatched in its field. First published in 1973, it is a magazine for anyone interested in early music and its contemporary interpretation. Alexander Scriabin's (1871_1915) work has traditionally focused on his music in the mid and late 1902s. The discussion of his personal philosophy and his influence on music also focuses on these two periods. Over the last few decades, the repertoire of British classical solo pianos has received increasing interest from researchers. From the piano rolls of the early 20th century, much can be inferred about the practice of romantic piano playing. Summary Haydn's most important piano works are the sonatas, which generally represent Haydn's development as a composer from the early to the last three sonata dates, 1794.

Keywords: piano, classic piano, performance, music

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Authors: M. Khalid, G. N. Singh

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In this paper, we have considered the problem of estimation for population mean, on current (second) occasion in the presence of random non response in two-occasion successive sampling under two phase set-up. Modified exponential type estimators have been proposed, and their properties are studied under the assumptions that numbers of sampling units follow a distribution due to random non response situations. The performances of the proposed estimators are compared with linear combinations of two estimators, (a) sample mean estimator for fresh sample and (b) ratio estimator for matched sample under the complete response situations. Results are demonstrated through empirical studies which present the effectiveness of the proposed estimators. Suitable recommendations have been made to the survey practitioners.

Keywords: successive sampling, random non-response, auxiliary variable, bias, mean square error

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Authors: N. Targui, H. Kahalerras

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The present work is a numerical simulation of nanofluids flow in a double pipe heat exchanger provided with porous baffles. The hot nanofluid flows in the inner cylinder, whereas the cold nanofluid circulates in the annular gap. The Darcy-Brinkman-Forchheimer model is adopted to describe the flow in the porous regions, and the governing equations with the appropriate boundary conditions are solved by the finite volume method. The results reveal that the addition of metallic nanoparticles enhances the rate of heat transfer in comparison to conventional fluids but this augmentation is accompanied by an increase in pressure drop. The highest heat exchanger performances are obtained when nanoparticles are added only to the cold fluid.

Keywords: double pipe heat exchanger, nanofluids, nanoparticles, porous baffles

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Authors: Tukundane Hillary

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This research paper analytically evaluates the project control practice levels used by the building construction companies within Kampala, Uganda. The research also assesses the outcome of project control practices on the productivity of the companies. The research was performed to ascertain the current control practices among 160 respondents from various construction companies registered with the Uganda Registration Services Bureau. This research used amalgamation from multiple literature to obtain the variables. The research adopts 34 standard control practices from four vital project control duties: planning, monitoring, analyzing, and reporting. These project control tasks were organized using mean response ratings grounded on their relevance to the construction companies. Results showed that evaluating performance with the use of curves (4.32), timely access to information and encouragement (4.55), report representation using quantitative tools 4.75, and cost value comparison application during analysis (4.76) were rated least among the control practices. On the other hand, the top project control practices included formulation of the project schedule (8.88), Project feasibility validation (8.86), Budgeting for each activity (8.84), Key project route definition (8.81), Team awareness of the budget (8.77), Setting realistic targets for projects (8.50) and Consultation from subcontractors (8.74). From the results obtained by the sample respondents specified, it can be concluded that planning is the most vital project control task practiced in the building construction industry in Uganda. In addition, this research ascertained a substantial relationship between project control practices and the performance of building construction companies. Accordingly, this research recommends that project control practices be effectively observed by both contracting and consulting companies to enhance their overall performance and governance.

Keywords: cost value, project control, cost control, time control, project performance, control practices

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Authors: Shan-Ken Chine

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This research aims to a one-year course run of String Music Appreciation, an international online course launched on the British open education platform. It explains how to present music teaching videos with three main features. They are music lesson explanations, instrumental playing demonstrations, and live music performances. The plan of this course is with four major themes and a total of 97 steps. In addition, the paper also uses the testing data provided by the education platform to analyze the performance of learners and to understand the operation of the course. It contains three test data in the statistics dashboard. They are course-run measures, total statistics, and statistics by week. The paper ends with a review of the course's star rating in this one-year run. The result of this course run will be adjusted when it starts again in the future.

Keywords: music online courses, MOOCs, ubiquitous learning, string music, general music education

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Authors: Ali Riza Perçin, Eser Bingül

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Internet technologies have created opportunities with which people share their ideologies, thoughts and products. This virtual world, named social media has given the chance of gathering individual users and people from the world's remote locations and establishing an interaction between them. However, to an increasingly higher degree terrorist organizations today use the internet and most notably social-network media to create the effects they desire through a series of on-line activities. These activities, designed to support their activities, include information collection (intelligence), target selection, propaganda, fundraising and recruitment to name a few. Meanwhile, these have been used as the most important tool for recruitment especially from the different region of the world, especially disenfranchised youth, in the West in order to mobilize support and recruit “foreign fighters.” The recruits have obtained the statue, which is not accessible in their society and have preferred the style of life that is offered by the terrorist organizations instead of their current life. Like other terrorist groups, for a while now the terrorist organization Islamic State (IS) in Iraq and Syria has employed a social-media strategy in order to advance their strategic objectives. At the moment, however, IS seems to be more successful in their on-line activities than other similar organizations. IS uses social media strategically as part of its armed activities and for the sustainability of their military presence in Syria and Iraq. In this context, “Generation Y”, which could exist at the critical position and undertake active role, has been examined. Additionally, the explained characteristics of “Generation Y” have been put forward and the duties of families and society have been stated as well.

Keywords: social media, "generation Y", terrorist organization, islamic state IS

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Authors: Bersufekad Wubie

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Introduction: Near visual impairment is presenting near visual acuity of the eye worse than N6 at a 40 cm distance. Teachers' regular duties, such as reading books, writing on the blackboard, and recognizing students' faces, need good near vision. If a teacher has near-visual impairment, the work output is unsatisfactory. Objective: The study was aimed to assess the prevalence and associated factors near vision impairment among school teachers at Gondar city Northwest Ethiopia, August 2022. Methods: To select 567 teachers in Gondar city schools, an institutional-based cross-sectional study design with a multistage sampling technique were used. The study was conducted in selected schools from May 1 to May 30, 2022. Trained data collectors used well-structured Amharic and English language questionnaires and ophthalmic instruments for examination. The collected data were checked for completeness and entered into Epi data version 4.6, then exported to SPSS version 26 for further analysis. A binary and multivariate logistic regression model was fitted. And associated factors of the outcome variable. Result: The prevalence of near visual impairment was 64.6%, with a confidence interval of 60.3%–68.4%. Near visual impairment was significantly associated with age >= 35 years (AOR: 4.90 at 95% CI: 3.15, 7.65), having prolonged years of teaching experience (AOR: 3.29 at 95% CI: 1.70, 4.62), having a history of ocular surgery (AOR: 1.96 at 95% CI: 1.10, 4.62), smokers (AOR: 2.21 at 95% CI: 1.22, 4.07), history of ocular trauma (AOR : 1.80 at 95%CI:1.11,3.18 and uncorrected refractive error (AOR:2.01 at 95%CI:1.13,4.03). Conclusion and recommendations: This study showed the prevalence of near vision impairment among school teachers was high, and it is not a problem of the presbyopia age group alone; it also happens at a young age. So teachers' ocular health should be well accommodated in the school's eye health.

Keywords: Gondar, near visual impairment, school, teachers

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Authors: Hannah F. Opayinka, Adedayo A. Adepoju

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This study is an extension of a prior study on the modification of the existing m-out-of-n (moon) bootstrap method for heavy-tailed distributions in which modified m-out-of-n (mmoon) was proposed as an alternative method to the existing moon technique. In this study, both moon and mmoon techniques were applied to two real income datasets which followed Lognormal and Pareto distributions respectively with finite variances. The performances of these two techniques were compared using Standard Error (SE) and Root Mean Square Error (RMSE). The findings showed that mmoon outperformed moon bootstrap in terms of smaller SEs and RMSEs for all the sample sizes considered in the two datasets.

Keywords: Bootstrap, income data, lognormal distribution, Pareto distribution

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Authors: Mkhinini Maher, Knani Jilani

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We present in this work the performances of a mobile omnidirectional robot through evaluating its management of the redundancy of actuation. Thus we come to the predictive control implemented. The distribution of the wringer on the robot actions, through the inverse pseudo of Moore-Penrose, corresponds to a -geometric- distribution of efforts. We will show that the load on vehicle wheels would not be equi-distributed in terms of wheels configuration and of robot movement. Thus, the threshold of sliding is not the same for the three wheels of the vehicle. We suggest exploiting the redundancy of actuation to reduce the risk of wheels sliding and to ameliorate, thereby, its accuracy of displacement. This kind of approach was the subject of study for the legged robots.

Keywords: mobile robot, actuation, redundancy, omnidirectional, inverse pseudo moore-penrose, reductive control

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Authors: Nordin Mamat, Abdul Rahim Razalli, Loy Chee Luen, Abdul Talib Hashim

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This study was designed to investigate preschool environment in multi-ethnic preschool in Malaysia. The objectives are to identify the quality of work environment in multi-ethnic preschools; to investigate the practices of teachers’ role and responsibility; and to identify the quality of human resources. The study involved 2004 respondents who are the staff of multi-ethnic preschool from the government agency who provide preschool service. This study was conducted using a mixed method in which questionnaires and interviews were used to obtain data from respondents. The findings were analysed using mean and used Likert scale to determine the three-stage level such as the high, moderate and low. Findings indicated that the work environment at a moderate level, but the facilities provided insufficient to carry out educational activities with children. The result based on ranking of duties and responsibilities of teachers in multi-ethnic preschool shows the teachers practice daily record of children's development is very little, that only 65 persons are recording the child's development. The poor ratio of teachers and child in multi-ethnic preschool is between 25 to 35 children per class which means the children need a lot of attention. Meanwhile, the work environment is moderate with a mean score of 3.65 and overall mean score for level of staff career development 3.66 also moderate. The findings indicate the facilities provided in their workplace and staff career development requires improvements. Overall, the level of work environment is moderate, and it needs an improvement in term of facilities.

Keywords: environment, human resources, multi-ethnic preschool, quality teacher

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Authors: Arabi Nour El Houda, Iratni Aicha, Talaighil Razika, Bruno Capoen, Mohamed Bouazaoui

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TiO2 thin films have been prepared by the sol-gel dip-coating technique in order to elaborate antireflective thin films for monocrystalline silicon (mono-Si). The titanium isopropoxyde was chosen as a precursor with hydrochloric acid as a catalyser for preparing a stable solution. The optical properties have been tailored with varying the solution concentration, the withdrawn speed, and the heat-treatment. We showed that using a TiO2 single layer with 64.5 nm in thickness, heat-treated at 450°C or 300°C reduces the mono-Si reflection at a level lower than 3% over the broadband spectral do mains [669-834] nm and [786-1006] nm respectively. Those latter performances are similar to the ones obtained with double layers of low and high refractive index glasses respectively.

Keywords: thin film, dip-coating, mono-crystalline silicon, titanium oxide

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Authors: Serkan Aras, Emrah Gulay

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Combining various forecasting models is an important tool for researchers to attain more accurate forecasts. A great number of papers have shown that selecting single models as dissimilar models, or methods based on different information as possible leads to better forecasting performances. However, there is not a certain rule regarding the number of single models to be used in any combining methods. This study focuses on determining the optimal or near optimal number for single models with the help of statistical tests. An extensive experiment is carried out by utilizing some well-known time series data sets from diverse fields. Furthermore, many rival forecasting methods and some of the commonly used combining methods are employed. The obtained results indicate that some statistically significant performance differences can be found regarding the number of the single models in the combining methods under investigation.

Keywords: combined forecast, forecasting, M-competition, time series

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Authors: Michael Nthabiseng Moeti, Makhulu Relebogile Langa, Joey Jansen van Vuuren

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This paper examines the utilization of personal electronic devices like laptops, tablets, and smartphones for professional duties within a financial organization. This phenomenon is known as bring your own device (BYOD). BYOD accords employees the freedom to use their personal devices to access corporate resources from anywhere in the world with Internet access. BYOD arrangements introduce significant security risks for both organizations and users. These setups change the threat landscape for enterprises and demand unique security strategies, as conventional tools tailored for safeguarding managed devices fall short in adequately protecting enterprise assets without active user cooperation. This paper applies protection motivation theory (PMT) to highlight behavioral risks from BYOD users that may impact the security of financial institutions. Thematic analysis was applied to gain a comprehensive understanding of how users perceive this phenomenon. These findings demonstrates that the existence of a security policy does not ensure that all employees will take measures to protect their personal devices. Active promotion of BYOD security policies is crucial for financial institution employees and management. This paper developed a BYOD security model which is useful for understanding compliant behaviors. Given that BYOD security is becoming a major concern across financial sector, it is important. The paper recommends that future research could expand the number of universities from which data is collected.

Keywords: BYOD, information security, protection motivation theory, security risks, thematic analysis

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Authors: Shiori Ishida, Hiromi Okuno, Hisato Igarashi, Akemi Yamazaki, Hiroko Takahashi

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The purpose of this study was to clarify the differences and similarities regarding the social support of fathers and mothers towards considering increased assistance for the paternity of children with developmental disabilities. Written questionnaires were completed by fathers (n=85) and mothers (n=101) of children using rehabilitation facilities between infancy and 5 years of age. The survey contained multiple-choice questions on four categories: information support (6 items), emotional support (7 items), evaluation support (3 items), and daily living support (3 items). Regarding information support, fathers answered ‘spouse’ as the provider in over 50% of cases for all 6 items, which was significantly different compared with mothers (all p < 0.001). For emotional support, fathers were significantly more likely to get support from the workplace (p < 0.001) and from spouse (p < 0.001). The ‘evaluation support’ did not have significant differences for fathers in all the items, but the most frequent support providers were ‘spouses’. ‘Daily living support’ was significantly different from fathers in the workplace (p < 0.000) in terms of make allowances for work and duties. Thus, it appeared that fathers had fewer social support sources as compared with mothers and limited non-spouse support. The understanding of developmental disabilities, acquisition of methods of rehabilitation, and sources of support might have been inadequately addressed among fathers, which could be a hindrance to the involvement of fathers in the rearing of children with developmental disabilities. On the other hand, we also observed that some fathers were involved in the care of developmentally troubled children while providing mental support for their spouse, cooperating with housework, and adjusting their work life. However, the results on the external and social backgrounds of fathers indicated a necessity for greater empowerment and peer support to improve the paternal care of children with developmental disabilities in the family survey.

Keywords: children with developmental disabilities, family support, father, social support

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Authors: Bagher Aziz Kalantari, Javad Rafiei, Mohamad Reza Talei Bavil Olyai

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Disclosed is a method of preparing a pigmentary chromium oxide nano particles having 50 percent particle size less than about 100nm. According to the disclosed method, a substantially dry solid composition of potassium dichromate and carbon active is heated in CO2 atmosphere to a temperature of about 600ºc for 1hr. Thereafter, the solid Cr2O3 product was washed twice with distilled water. The other aim of this study is to assess both the colouring performance and the potential of nano-pigments in the ceramic tile decoration. The rationable consists in nano-pigment application in several ceramics, including a comparison of colour performance with conventional micro-pigments.

Keywords: green chromium oxide, nano particles, colour performances, particle size

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Authors: Monika Szpringer, Mariola Wojciechowska, Robert Dutkiewicz, Grażyna Nowak-Starz, Marzena Olędzka

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The main aim of this article is to determine the phenomenon of stress among academic teachers as well as to identify the extent to which the teachers experience work-related psychological risks. It is also important to support academic teachers trade unions in scope of stress-oriented activities, including psychological dangers in the assessment of risk in the workplace (college). The authors used a method of a diagnostic survey with a polling as a technique and authors’ questionnaire as a tool. The survey was conducted between September and December of 2013 and it comprised 1890 academic teachers from five voivodeships. The study reveals that 84.0% of the respondents found the work of an academic teacher to be borne with a considerable stress. The percentage values of the most frequent causes of stress are as follows: frequent changes of both organisational and didactic matters as well as overwhelming bureaucracy (77.8 %), time pressure regarding professional development and related risk of losing job (68.2 %), difficult working conditions (45.4%), conflicts and rivalry between teachers (44.1%), excessive amount of duties as well as increasing requirements and demanding attitude of students (33.7%). Work-related stress affects or significantly affects the private life of 69 % and 66.4 % of the respondents respectively. The majority of the people surveyed deals with stress by undertaking various activities, with 40% pointing at using various substances, mostly cigarettes and alcohol (p > 0,05) Physical ailments were experienced by 81% of the respondents, in 9% they were rare and 8 % of the respondents had never experienced such disorders. The entire group of the surveyed people (100 %) claimed that they have no possibility of contacting a psychologist at their workplace (p > 0.05), and they stated that the need of contacting specialists does exist.

Keywords: stress, academic teachers, psychological risks, work-related

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Authors: F. Sallem, B. Dahhou, A. Kamoun

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In this work, the main problem considered is the detection and the isolation of the actuator fault. A new formulation of the linear system is generated to obtain the conditions of the actuator fault diagnosis. The proposed method is based on the representation of the actuator as a subsystem connected with the process system in cascade manner. The designed formulation is generated to obtain the conditions of the actuator fault detection and isolation. Detectability conditions are expressed in terms of the invertibility notions. An example and a comparative analysis with the classic formulation illustrate the performances of such approach for simple actuator fault diagnosis by using the linear model of nuclear reactor.

Keywords: actuator fault, Fault detection, left invertibility, nuclear reactor, observability, parameter intervals, system inversion

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Authors: Nurul Amziah Md Yunus, Izhal Abdul Halin, Nasri Sulaiman, Noor Faezah Ismail, Nik Hasniza Nik Aman

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Nanotechnology has become the world attention in various applications including the solar cells devices due to the uniqueness and benefits of achieving low cost and better performances of devices. Recently, thin film solar cells such as cadmium telluride (CdTe), copper-indium-gallium-diSelenide (CIGS), copper-zinc-tin-sulphide (CZTS), and dye-sensitized solar cells (DSSC) enhanced by nanotechnology have attracted much attention. Thus, a compilation of nanotechnology devices giving the progress in the solar cells has been presented. It is much related to nanoparticles or nanocrystallines, carbon nanotubes, and nanowires or nanorods structures.

Keywords: nanotechnology, nanocrystalline, nanowires, carbon nanotubes, nanorods, thin film solar cells

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Authors: S. Paengkoum, P. Paengkoum, W. Kaewwongsa

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Twenty-four male growing goats were randomly assigned to a Randomized Complete Block Design. Dietary treatments were different level of feeding concentrate diet at 1.0, 1.5, 2.0, and 2.5% of body weight (BW). The results showed that average daily gain, microbial N supply, N retention of meat goats in the group of feeding level at 2.0% BW and 2.5% BW were significantly higher (P<0.05) than those goats fed with feeding levels of 1.0% BW and 1.5% BW. Based on this result the conclusion can be made that using 75% fermented cassava pulp by Saccharomyces cerevisiae as the main source of protein to completely replace soybean meal was beneficial to meat goats in terms of feed intake. The feeding concentrate at levels between 2.0-2.5% BW gives highest in the growth of meat goat in this experiment.

Keywords: cassava pulp, yeast, goat, nitrogen retention

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Authors: Norhashidah Hj. Mohd Ali, Teng Wai Ping

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In this paper, we present a high order group explicit method in solving the two dimensional Helmholtz equation. The presented method is derived from a nine-point fourth order finite difference approximation formula obtained from a 45-degree rotation of the standard grid which makes it possible for the construction of iterative procedure with reduced complexity. The developed method will be compared with the existing group iterative schemes available in literature in terms of computational time, iteration counts, and computational complexity. The comparative performances of the methods will be discussed and reported.

Keywords: explicit group method, finite difference, helmholtz equation, rotated grid, standard grid

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Authors: Naila Awan, Shahrukh Inam

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This study was conducted to highlight the role of basic health units in district Swabi, which provides primary health services to the people of district Swabi having four tehsils. Tehsil Swabi was selected purposively for the study. Three villages were purposively selected from district Swabi. A sum of 110 respondents was randomly selected for interview i.e., 27 from Botakaa, 39 from Gulatee, and 44 from Darra Cham, using proportion allocation sampling technique. A pretested and well-designed interview schedule was used to collect as per the objective and Chi square test was applied to find an association between the quality of medicines and health improvement. The output of the test shows that the government was doing its best and providing enough facilities to the individuals at the healthcare units, and they were utilizing them. These resources were easily accessible to the people of the community. Medicines provided by the government were of good quality and quantity. There were also school health sessions and community health sessions (SHS/CHS) to deliver useful information and awareness regarding health problems and diseases were conducted. The staff of the BHU was present at work time and was performing their duties. The respondents seemed satisfied with their behavior and the duty of the staff. However, there were no emergency resources existing at the BHU after the working hours of the medical staff. It is recommended that government should provide appropriate quantity and quality of medicines to the basic health units so that these healthcare units don’t have to face any shortages regarding medicines at the end of the month. In addition, laboratory and blood testing facilities need to be provided in the basic health units, and also the infrastructure should be made suitable, satisfactory, and more functional.

Keywords: community health session, basic health units, outpatient department, tuberculosis

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Authors: Mostafa Rajabi, Kazem Mahanpoor

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Performances of the methyl red (MR) dye adsorption on poly(methyl methacrylate)/graphene oxide (PMMA/GO) and poly(methyl methacrylate)/graphene oxide-Fe3O4 (PMMA/GO-Fe3O4) nanocomposites as adsorbents were investigated. Our results showed that for adsorption of MR dye on PMMA/GO-Fe3O4 and PMMA/GO nanocomposites, 80 minutes, 298 K, and pH 2 were the best contact time, temperature and pH value for process, respectively, because the optimum adsorption of the MR dye with both nanocomposite adsorbents were observed in these values of the parameters. The equilibrium study results showed that PMMA/GO-Fe3O4 and PMMA/GO were suitable adsorbents for MR dye removing and were best in agreement with the Langmuir isotherm model.

Keywords: adsorption, isotherm, methyl methacrylate, methyl red, nanocomposite, nano magnetic Fe3O4

Procedia PDF Downloads 187

Authors: M. Khalid, G. N. Singh

Abstract:

In this paper, we have considered the problems of estimation for the population mean on current (second) occasion in two-occasion successive sampling under random non-response situations. Some modified exponential type estimators have been proposed and their properties are studied under the assumptions that the number of sampling unit follows a discrete distribution due to random non-response situations. The performances of the proposed estimators are compared with linear combinations of two estimators, (a) sample mean estimator for fresh sample and (b) ratio estimator for matched sample under the complete response situations. Results are demonstrated through empirical studies which present the effectiveness of the proposed estimators. Suitable recommendations have been made to the survey practitioners.

Keywords: modified exponential estimator, successive sampling, random non-response, auxiliary variable, bias, mean square error

Procedia PDF Downloads 349

Authors: Jong-Ho Moon, Dong-Ho Lee, Hyunuk Kim, Young Cheol Park, Jong-Seop Lee, Jae-deok Jeon, Hyung-Keun Lee

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A novel membrane reactor process for DMC synthesis from carbon dioxide has been developing in Korea Institute of Energy Research. The scheme of direct synthesis of DMC from CO₂ and Methanol is 'CO₂ + 2MeOH ↔ DMC + H₂O'. Among them, reactants are CO₂ and MeOH, product is DMC, and byproduct is H₂O (water). According to Le Chatelier’s principle, removing byproduct (water) can shift the reaction equilibrium to the right (DMC production). The main purpose of this process is removing water during the reaction. For efficient in situ water removal (dehydration) and DMC separation, zeolite 4A membranes with very small pore diameter and hydrophilicity were introduced. In this study, pervaporation performances of binary and ternary DMC / methanol / water mixtures were evaluated.

Keywords: dimehtyl carbonate, methanol, water, zeolite membrane, pervaporation

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Authors: A. Aloga, A. S. Aloga

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The study examined the influence of instructional supervision on teachers’ performance in secondary schools in Otukpo LGA of Benue State. The study was guided by four research questions and four hypotheses. The study employed a descriptive research design. The population of the study comprised of 579 teachers in 26 public secondary schools out of which 236 respondents were sampled and used as the studied population. The instrument used for data collection was a structured questionnaire, titled ‘Instructional Supervision and Teachers Performance Questionnaire (ISTPQ)’ The data was analyzed using descriptive statistics of mean and standard deviation to answer the research questions. And Chi-Square Statistics was used to test the hypotheses at 0.05 level of significance. The study found that instructional supervision has a significant influence on teachers’ lesson planning, effective teaching, teachers’ class attendance and teachers’ classroom management. The study concluded that instructional supervision influences teachers’ performance. It was recommended that; instructional supervisors should always give useful suggestions as regards the best instructional practices needed by teachers in enhancing lesson planning. The government should recruit more trained and qualified instructional supervisors to be able to meet the intending demands of instructional supervision. This will relieve the existing few qualified instructional supervisors from work overload which may result to ineffectiveness and poor performance of their duties. Conferences and seminars should be organized for instructional supervisors from time to time to cater for the professional assistance needed by teachers. The state government should always provide adequate funding for these conferences and seminars since it provides an avenue for acquiring new knowledge in educational development by teachers among others.

Keywords: influence, instructional supervision, teachers’ performance, secondary schools

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Authors: M. Laissaoui

Abstract:

The present work has for objective the simulation of a hybrid solar combined cycle power plant, compared with combined cycle conventional (gas turbine and steam turbine), this type of power plants disposed an solar tour (heliostat field and volumetric receiver) insurant a part of the thermal energy necessary for the functioning of the gas turbine. This solar energy serves to feed with heat the combustion air of the gas turbine when he out of the compressor and the front entered the combustion chamber. The simulation of even central and made for three zones deferential to know the zone of Hassi R' mel, Bechare, and the zone of Messaad wilaya of El djelfa. The radiometric and meteorological data arise directly from the software meteonorme 7. The simulation of the energy performances is made by the software TRNSYS 16.1.

Keywords: concentrating solar power, heliostat, thermal, Algeria

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Authors: S. Saeed, T. Butt, M. Rehan, S. Khaliq

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Objective: To determine the frequency of pre-analytical errors in samples taken from patients for various lab tests at Fauji Foundation Hospital, Rawalpindi. Material and Methods: All the lab specimens for diagnostic purposes received at the lab from Fauji Foundation hospital, Rawalpindi indoor and outdoor patients were included. Total number of samples received in the lab is recorded in the computerized program made for the hospital. All the errors observed for pre-analytical process including patient identification, sampling techniques, test collection procedures, specimen transport/processing and storage were recorded in the log book kept for the purpose. Results: A total of 476616 specimens were received in the lab during the period of study including 237931 and 238685 from outdoor and indoor patients respectively. Forty-one percent of the samples (n=197976) revealed pre-analytical discrepancies. The discrepancies included Hemolyzed samples (34.8%), Clotted blood (27.8%), Incorrect samples (17.4%), Unlabeled samples (8.9%), Insufficient specimens (3.9%), Request forms without authorized signature (2.9%), Empty containers (3.9%) and tube breakage during centrifugation (0.8%). Most of these pre-analytical discrepancies were observed in samples received from the wards revealing that inappropriate sample collection by the medical staff of the ward, as most of the outdoor samples are collected by the lab staff who are properly trained for sample collection. Conclusion: It is mandatory to educate phlebotomists and paramedical staff particularly performing duties in the wards regarding timing and techniques of sampling/appropriate container to use/early delivery of the samples to the lab to reduce pre-analytical errors.

Keywords: pre analytical lab errors, tertiary care hospital, hemolyzed, paramedical staff

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Authors: K. Touafek, A. Khelifa, I. Tabet, H. Haloui, H. Bencheikh El Houcine, M. Adouane

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Hybrid photovoltaic thermal (PVT) collectors allow simultaneous production of electrical energy thus heat energy. There are several configurations of hybrid collectors (to produce water or air). For hybrids water collectors, there are several configurations that differ by the nature of the absorber (serpentine, tubes...). In this paper, an absorber tank is studied. The circulation of the coolant is natural (we do not use the pump). We present the obtained results in our experimental study and we analyzed the data, and then we compare the results with the theory practices. The electrical performances of the hybrid collector are compared with those of conventional photovoltaic module mounted on the same structure and measured under the same conditions. We conducted experiments with natural circulation of the coolant (Thermosyphon), for a flow rate of 0.025kg/m².

Keywords: experimental, photovoltaic, solar, temperature, tank

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Authors: L. Bokopane, K. Kusakana, H. J. Vermaark

Abstract:

The success of renewable powered electric vehicle charging station in isolated areas depends highly on the availability and sustainability of renewable resources all year round at a selected location. The main focus of this paper is to discuss the possible charging strategies that could be implemented to find the best possible configuration of an electric Tuk-Tuk charging station at a given location within South Africa. The charging station is designed, modeled and simulated to evaluate its performances. The techno-economic analysis of different feasible supply configurations of the charging station using renewable energies is simulated using HOMER software and the results compared in order to select the best possible charging strategies in terms of cost of energy consumed.

Keywords: electric tuk-tuk, renewable energy, energy Storage, hybrid systems, HOMER

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