A Calculation Model to Estimate the Electrical Performance of a Photovoltaic Panel

In this study, the thermal and electrical modeling of a photovoltaic panel is performed to evaluate its temperature profiles, electrical efficiency and the electrical power supplied. The energy balance equations under transient conditions of all the layers that make up the panel are discretized by the finite difference technique and solved with the implicit method. The results are validated with experimental data provided by an experimental set-up located on the roof of a building of the Department of Mechanical, Energy and Management Engineering (DIMEG) of the University of Calabria. The comparison with the experimental data allows us to see an excellent approximation of the distribution of temperatures inside the panel and in particular of the photovoltaic cells, accurately evaluating the effect on electrical efficiency and the electrical power supplied. The validation was performed with reference to a clear winter day and a clear summer day. The mean square error was about 1.5°C on the panel temperature and about 3 W on the electrical power (1.2% of the maximum power).

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Cooling of a heating cylinder by confined impacting air jets

International Journal of Numerical Methods for Heat &amp Fluid Flow ◽

10.1108/hff-10-2015-0415 ◽

2016 ◽

Vol 26 (7) ◽

pp. 2013-2032 ◽

Cited By ~ 2

Author(s):

Nicolas Chauchat ◽

Eric Schall ◽

Mathieu Mory ◽

Marta de la Llave Plata ◽

Vincent G. Couaillier

Keyword(s):

Experimental Data ◽

Mechanical Energy ◽

Electrical Power ◽

Electrical Energy ◽

Numerical Results ◽

Content Type ◽

Air Jets ◽

Velocity Magnitude ◽

Air Jet ◽

Set Up

Purpose The purpose of this paper is to investigate a new cooling process of a heated cylinder with confined impacting air jet. Design/methodology/approach To do this the authors used experience-numerical and numerical-numerical comparisons. The experimental facility, designed and built at the Pau University, consists in air jets impacting around a heated circular cylinder. As the inlet velocity magnitude is low (Vin=4.37 m/s – Machin=0.0125), using a compressible solver for numerical simulations presents a number of difficulties. For this low Mach number configuration, the authors compare the performance of three different solvers in this paper. Two of them are compressible, one based on the finite volume approach and the other on a discontinuous Galerkin method, and the third one is an incompressible solver. Some of the numerical results are compared to experimental data. Findings Comparisons between the results from 3D and 2D computations support the relevance of 2D models. Some of the numerical results are compared to experimental data. Research limitations/implications The confined aspect of the set-up reduces experimental measurement to intrusive measures. It should be noted that the temperature measurement given by thermocouples is always considered as “global” or “average”. Originality/value Future aircraft technology will increasingly rely on electrical power. The substitution of mechanical energy by electrical energy will lead to an increasing amount of heat power that need be evacuated. Innovative cooling processes have to be set up according to constraints imposed by the technological design.

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A fuzzy neural network approach for modeling the growth kinetics of FeB and Fe2B layers during the boronizing process

Matériaux & Techniques ◽

10.1051/mattech/2019002 ◽

2018 ◽

Vol 106 (6) ◽

pp. 603 ◽

Cited By ~ 2

Author(s):

Bendaoud Mebarek ◽

Mourad Keddam

Keyword(s):

Neural Network ◽

Experimental Data ◽

Fuzzy Neural Network ◽

Treatment Time ◽

Calculation Model ◽

Average Error ◽

Network Approach ◽

Neural Network Approach ◽

Fuzzy Neural ◽

Kinetics Of

In this paper, we develop a boronizing process simulation model based on fuzzy neural network (FNN) approach for estimating the thickness of the FeB and Fe2B layers. The model represents a synthesis of two artificial intelligence techniques; the fuzzy logic and the neural network. Characteristics of the fuzzy neural network approach for the modelling of boronizing process are presented in this study. In order to validate the results of our calculation model, we have used the learning base of experimental data of the powder-pack boronizing of Fe-15Cr alloy in the temperature range from 800 to 1050 °C and for a treatment time ranging from 0.5 to 12 h. The obtained results show that it is possible to estimate the influence of different process parameters. Comparing the results obtained by the artificial neural network to experimental data, the average error generated from the fuzzy neural network was 3% for the FeB layer and 3.5% for the Fe2B layer. The results obtained from the fuzzy neural network approach are in agreement with the experimental data. Finally, the utilization of fuzzy neural network approach is well adapted for the boronizing kinetics of Fe-15Cr alloy.

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CARBON FOOTPRINT ASSESSMENT AT UNIVERSITI TEKNOLOGI MARA SERI ISKANDAR CAMPUS, MALAYSIA

Malaysian Journal of Sustainable Environment ◽

10.24191/myse.v2i1.5576 ◽

2017 ◽

Vol 2 (1) ◽

pp. 59

Author(s):

Nor Izana Mohd Shobri ◽

Wan Noor Anira Hj Wan Ali ◽

Norizan Mt Akhir ◽

Siti Rasidah Md Sakip

Keyword(s):

Total Energy ◽

Carbon Footprint ◽

Electrical Power ◽

Total Carbon ◽

Green House ◽

Green House Gas ◽

Carbon Footprint Assessment ◽

The University ◽

Electrical Consumption

The purpose of this study is to assess the carbon footprint emission at UiTM Perak, Seri Iskandar Campus. The assessment focuses on electrical power and transportation usage. Questionnaires were distributed to the staffs and students to survey their transportation usage in the year 2014 while for electrical consumption, the study used total energy consumed in the year 2014. Data was calculating with the formula by Green House Gas Protocol. Total carbon footprint produced by UiTM Perak, Seri Jskandar Campus in the year 2014 is 11842.09 MTC02' The result of the study is hoped to provide strategies for the university to reduce the carbon footprint emission.

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Formation and Development of the Pre-Professional Training System of Foreign Medical Applicants in Ukraine (Historical and Educational Aspect)

Comparative Professional Pedagogy ◽

10.2478/rpp-2014-0042 ◽

2014 ◽

Vol 4 (3) ◽

pp. 95-98

Author(s):

Iana Proskurkina

Keyword(s):

Foreign Students ◽

Professional Training ◽

Training System ◽

Further Education ◽

Effective System ◽

History Of ◽

Set Up ◽

The University ◽

History Of Formation ◽

Educational Aspect

Abstract The growing number of foreign applicants looking forward to getting education in Ukrainian medical universities makes us find the ways how to improve and make effective the pre-professional training system of foreign medical applicants for further education. The article deals with the issues of the history of formation and development of the preprofessional training system of foreign medical applicants in Ukraine. On the ground of the electronic databases of the official websites of higher educational establishments, the data on years of opening first offices of the dean, departments and preparatory faculties for foreign medical applicants in Ukrainian medical universities are analyzed and systematized. Also the data on the setting up preparatory faculties at other universities who carry out licensed training of foreign students of the medical profile are presented. The data on the operating and management of such institutions in the system of the University administration are generalized. It’s revealed that during the years of its functioning the pre-professional training has changed, in particular the system was commercialized and the institutions involved in training foreign applicants have been reorganized. The modern trends in teaching foreign medical students at the preparatory faculties of the Ukrainian medical universities are displayed. Based on the analysis of the data it is concluded that the system of the pre-professional training of foreign medical applicants was set up in the 50s-60s years of the twentieth century. During this time, some positive experience in the preparation of future international medical specialists has been gained. The system of the pre-professional training of foreign medical applicants has been comprehensively improved and an effective system of managing foreign medical applicants has been created.

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Process design and equipment selection for optimized steam and power concepts – the “zero” process steam sugar factory

Sugar Industry ◽

10.36961/si25907 ◽

2020 ◽

pp. 40-50

Author(s):

Boris Morgenroth ◽

Thomas Stark ◽

Julian Pelster ◽

Harjeet Singh Bola

Keyword(s):

Process Design ◽

Sugar Industry ◽

Electrical Power ◽

Power Requirement ◽

Equipment Selection ◽

Good Potential ◽

Set Up ◽

The Right ◽

Key Aspects ◽

Steam Drying

Optimization of process steam requirement in order to maximize sugar recovery and export power along with manpower optimization is a must for sugar factories to survive under difficult conditions and to earn additional revenues. The process steam demand of greenfield and revamped plants has been reduced to levels of 32–38% from originally more than 50% steam on cane in the case of the brownfield plants. In addition, significant improvement in the power requirement of the plants has been achieved. Bagasse drying offers a good potential to improve the power export. Different available concepts are compared with a focus on bagasse steam drying and low temperature bagasse drying. In order to set up an optimized highly efficient plant or to optimize an existing plant to achieve competitive benchmarks, good process design and the right equipment selection are very important. Experience has been gained with multiple stage or double effect crystallization in the beet sugar industry offering further steam optimization potential. Vapour recompression is also an option to substitute live steam by electrical power. This even provides options to reduce the steam demand from the power plant for the sugar process down to zero. Key aspects concerning the process design and equipment selection are described.

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Effect of Surgical Versus Pharmacological Decompression of Ludwig’s Angina on Airway Compromise among Nigerian Patients

Journal of Dentistry and Oral Sciences ◽

10.37191/mapsci-2582-3736-2(1)-024 ◽

2020 ◽

Author(s):

Ekaniyere EB

Keyword(s):

Length Of Hospital Stay ◽

Surgical Decompression ◽

Airway Compromise ◽

Inclusion Criteria ◽

Hospital Stays ◽

Ludwig’S Angina ◽

The Mean ◽

The University ◽

Ludwig's Angina ◽

Gender Type

Background: Even though the decompression of the cellulitis phase of Ludwig’s angina (LA) by surgical or pharmacological approach is well documented, it is unclear which approach is more effective. Objective: We aim to compare the outcome of treatment between surgical versus pharmacological decompression in patients with LA. Subjects and Methods: A retrospective cohort study was designed. Data were collected from the case notes of patients that met the inclusion criteria from 2004 to 2018 at the University of Benin Teaching Hospital, Nigeria.The data were age, gender, type of decompression approach, length of hospital stay (LOS) and airway compromise. Result: A total of 62 patients comprising 37(59.7%) surgical decompression group and 25(40.3%) pharmacological decompression group were studied. Thirty-six (58.1%) males and 26 (41.9%) females were studied. Their mean age and standard deviation were 40.6 years and 11.9 years respectively. The mean length of hospital stays between the pharmacological and surgical decompression groups were 8.05 days and 13.8 days respectively. The incidence of airway compromise in the surgical decompression group was 19.9% lower than that of the pharmacological decompression group (P=0.47), which was not significant. The type of decompression approach also failed to influence the incidence of airway compromise (P = 0.41). Conclusion: The use of surgical versus pharmacological decompression does not significantly alter the incidence of airway compromise in the management of LA. The Patients that had surgical decompression had a shorter stay in the hospital as compared to those who had pharmacological decompression. This was not statistically significant.

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Set up and management of a Data Science faculty at Shiga University

Impact ◽

10.21820/23987073.2019.10.18 ◽

2019 ◽

Vol 2019 (10) ◽

pp. 18-20

Author(s):

Akimichi Takemura

Keyword(s):

Data Science ◽

Science Faculty ◽

Knowledge And Skills ◽

International Trends ◽

Leading Position ◽

Global Understanding ◽

Set Up ◽

The University ◽

Do So ◽

Undergraduate Class

Shiga University opened the first data science faculty in Japan in April 2017. Beginning with an undergraduate class of 100 students, the Department has since established a Master's degree programme with 20 students in each annual intake. This is the first data science faculty in Japan and the University intends to retain this leading position, the Department is well-placed to do so. The faculty closely monitors international trends concerning data science and Artificial Intelligence (AI) and adapt its education and research accordingly. The genesis of this department marks a change in Japan's attitudes towards dealing with information and reflects a wider, global understanding of the need for further research in this area. Shiga University's Data Science department seeks to produce well-trained data scientists who demonstrate a good balance of knowledge and skills in each of the three key areas of data science.

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Adherence to Mediterranean Diet among Lebanese University Students

Nutrients ◽

10.3390/nu13041264 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1264

Author(s):

Joanne Karam ◽

Maria del Mar Bibiloni ◽

Mireille Serhan ◽

Josep A. Tur

Keyword(s):

University Students ◽

Mediterranean Diet ◽

Eating Habits ◽

Meat Products ◽

Older Students ◽

Adequate Intake ◽

Cross Sectional ◽

Adherence Score ◽

The Mean ◽

The University

Scarce studies described eating habits and diet quality among university students in Lebanon. The aim of this study is to assess the rate of adherence to the Mediterranean diet (MedDiet) among Lebanese university students. A cross-sectional nutritional survey was carried out on 525 students (53% men, 18–25 years old) from the University of Balamand, Lebanon. Adherence to the MedDiet was assessed using a validated 14-item MedDiet adherence score. Mean adherence to the MedDiet was 7.96 (standard deviation 2.2), and it was adequate in 59% of participants. Adherence to the MedDiet was higher in older students and nonsmokers. Legumes, vegetables, fruits, and nuts were consumed according to the MedDiet standards among a minimum of 48.4% and a maximum of 69.5% of participants. Chicken, turkey, or rabbit was preferred by 66.9% of participants instead of beef, pork, hamburgers, or sausages; however, just 56.2% of participants showed adequate intake of red meat, hamburger, or meat products. Only 28.8% of them referred to an adequate intake of fish or shellfish. Most of the participants (86.3%) used olive oil as the main added fat, and 67.2% reported a low intake of butter and derivatives. Sofrito was also very usual among participants (79.6%). Only half of the studied sample reported an adequate intake of sweet or carbonated beverages and commercial sweets or pastries. Among the assessed sample, half the participants showed adequate adherence to the MedDiet; however, the mean of adherence among the sample is low.

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Tissue Ki67 proliferative index expression and pathological changes in hemodialysis arteriovenous fistulae: Preliminary single-center results

The Journal of Vascular Access ◽

10.1177/11297298211015495 ◽

2021 ◽

pp. 112972982110154

Author(s):

Raffaella Mauro ◽

Cristina Rocchi ◽

Francesco Vasuri ◽

Alessia Pini ◽

Anna Laura Croci Chiocchini ◽

...

Keyword(s):

Morphological Changes ◽

Hot Spot ◽

Wall Thickening ◽

Proliferating Cells ◽

Ki 67 ◽

Group A ◽

The Mean ◽

Set Up ◽

Group B

Background: Arteriovenous fistula (AVF) for hemodialysis integrates outward remodeling with vessel wall thickening in response to drastic hemodynamic changes. Aim of this study is to determine the role of Ki67, a well-established proliferative marker, related to AVF, and its relationship with time-dependent histological morphologic changes. Materials and methods: All patients were enrolled in 1 year and stratified in two groups: (A) pre-dialysis patients submitted to first AVF and (B) patients submitted to revision of AVF. Morphological changes: neo-angiogenesis (NAG), myointimal thickening (MIT), inflammatory infiltrate (IT), and aneurysmatic fistula degeneration (AD). The time of AVF creation was recorded. A biopsy of native vein in Group A and of arterialized vein in Group B was submitted to histological and immunohistochemical (IHC) analysis. IHC for Ki67 was automatically performed in all specimens. Ki67 immunoreactivity was assessed as the mean number of positive cells on several high-power fields, counted in the hot spots. Results: A total of 138 patients were enrolled, 69 (50.0%) Group A and 69 (50.0%) Group B. No NAG or MIT were found in Group A. Seven (10.1%) Group A veins showed a mild MIT. Analyzing the Group B, a moderate-to-severe MIT was present in 35 (50.7%), IT in 19 (27.5%), NAG in 37 (53.6%); AD was present in 10 (14.5%). All AVF of Group B with the exception of one (1.4%) showed a positivity for Ki67, with a mean of 12.31 ± 13.79 positive cells/hot spot (range 0–65). Ki67-immunoreactive cells had a subendothelial localization in 23 (33.3%) cases, a myointimal localization in SMC in 35 (50.7%) cases. The number of positive cells was significantly correlated with subendothelial localization of Ki67 ( p = 0.001) and with NA ( p = 0.001). Conclusions: Native veins do not contain cycling cells. In contrast, vascular cell proliferation starts immediately after AVF creation and persists independently of the time the fistula is set up. The amount of proliferating cells is significantly associated with MIT and subendothelial localization of Ki67-immunoreactive cells, thus suggesting a role of Ki-67 index in predicting AVF failure.

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The Sankara Nethralaya Tamil Nadu Essilor Myopia (STEM) Study—Defining a Threshold for Non-Cycloplegic Myopia Prevalence in Children

Journal of Clinical Medicine ◽

10.3390/jcm10061215 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1215

Author(s):

Aparna Gopalakrishnan ◽

Jameel Rizwana Hussaindeen ◽

Viswanathan Sivaraman ◽

Meenakshi Swaminathan ◽

Yee Ling Wong ◽

...

Keyword(s):

Open Field ◽

Tamil Nadu ◽

Mean Difference ◽

School Vision ◽

Elite School ◽

Prevalence Estimates ◽

The Mean ◽

Clinically Significant ◽

Set Up ◽

Definition Of

The aim of this study was to investigate the agreement between cycloplegic and non-cycloplegic autorefraction with an open-field auto refractor in a school vision screening set up, and to define a threshold for myopia that agrees with the standard cycloplegic refraction threshold. The study was conducted as part of the Sankara Nethralaya Tamil Nadu Essilor Myopia (STEM) study, which investigated the prevalence, incidence, and risk factors for myopia among children in South India. Children from two schools aged 5 to 15 years, with no ocular abnormalities and whose parents gave informed consent for cycloplegic refraction were included in the study. All the children underwent visual acuity assessment (Pocket Vision Screener, Elite school of Optometry, India), followed by non-cycloplegic and cycloplegic (1% tropicamide) open-field autorefraction (Grand Seiko, WAM-5500). A total of 387 children were included in the study, of whom 201 were boys. The mean (SD) age of the children was 12.2 (±2.1) years. Overall, the mean difference between cycloplegic and non-cycloplegic spherical equivalent (SE) open-field autorefraction measures was 0.34 D (limits of agreement (LOA), 1.06 D to −0.38 D). For myopes, the mean difference between cycloplegic and non-cycloplegic SE was 0.13 D (LOA, 0.63D to −0.36D). The prevalence of myopia was 12% (95% CI, 8% to 15%) using the threshold of cycloplegic SE ≤ −0.50 D, and was 14% (95% CI, 11% to 17%) with SE ≤ −0.50 D using non-cycloplegic refraction. When myopia was defined as SE of ≤−0.75 D under non-cycloplegic conditions, there was no difference between cycloplegic and non-cycloplegic open-field autorefraction prevalence estimates (12%; 95% CI, 8% to 15%; p = 1.00). Overall, non-cycloplegic refraction underestimates hyperopia and overestimates myopia; but for subjects with myopia, this difference is minimal and not clinically significant. A threshold of SE ≤ −0.75 D agrees well for the estimation of myopia prevalence among children when using non-cycloplegic refraction and is comparable with the standard definition of cycloplegic myopic refraction of SE ≤ −0.50 D.

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