JournalTOCs

Advances in Image and Video Processing
Number of Followers: 24

This is an Open Access Journal

Open Access journal
ISSN (Print) 2054-7412
Published by Society for Science and Education

[4 journals]

Performance Evaluation of a Typical 50kWp Solar Park Village Energy Option
in Cameroon
- Authors: Julius K. Tangka; Mbi B Besong, Henri Grisseur Djoukeng
  Abstract: The Cameroon government brought up a project of decentralized off grid rural electrification using 50kW solar parks in some villages to curb the rampant power outages experienced in the country. Over 1000 of such plants are to be installed in the country. The first 50 were already installed since 2017 but no performance evaluation has been carried out to investigate if this option satisfies the aspiration of the users. Performance evaluation was carried out on a 50kW solar powered mini off-grid system in Cameroon, a module adopted by the government to solve rural electricity crises. The evaluation involved investigating the production conformity with design parameters and socioeconomic sustainability of the project. The system is made of 200 modules of 250 Wp and 192 batteries of 2 V/800 Ah each. The study involved monitoring the array, the final and reference yields, energy losses, and the performance ratio. During this period, the system produced an average daily energy generation of 73.04 kWh and 44.72 kWh as daily energy consumption with an average performance ratio of 17.10 % and capacity utilization factor of 6.07 %. The average reference yield, array yield, final yield, array capture loss and system loss for the system were of 5.23, 1.46, 0.66, 3.77 and 0.57 h/d respectively. Average array, inverter and system efficiencies were 42.83 %, 61.24 % and 26.23 % respectively. The results obtained show that for this location, about 25 % of the energy produced is not consumed even as the plant is not functioning to its full capacity. It was recommended that government should make a detailed feasibility study establishing the load consumption ability and the power curve of each village before doing the installations.
  PubDate: Fri, 24 Nov 2023 00:00:00 +000
Net Zero Energy Buildings and the cost per sf
- Authors: Sherif Attallah; Alireza Shayesteh
  Abstract: Zero energy buildings are created and constructed to use the least amount of energy feasible [1]. These structures can produce enough energy to meet or surpass their operating needs when a renewable energy source is added to them [1]. Most modern buildings consume a lot of energy to run the lights, heat the water, chill the air, and power personal electronics [2]. The large energy load will not be greatly mitigated by adding solar systems. However, there are other structures that achieve balance or even tilt the scales in the opposite direction. These are referred to as zero energy structures. The reductions in energy use and carbon footprint must be adjusted to account for real systems, such as the inhabitants and the local climate before renovations may be advised on a continental scale [3]. According to Delavar and Sahebi Energy is an essential resource for the economic growth of today's businesses [4]. Residential and commercial buildings must utilize a significant amount of energy to provide the services required. The total amount of energy consumed in this industry has been constantly increasing. Due to the large greenhouse gas emissions that arise, effective building management and energy conservation have become top priorities for the energy and environmental sectors all over the world. In this direction, net-zero energy buildings (NZEB) are a very effective way to minimize energy consumption and alleviate environmental impacts in buildings.
  PubDate: Sat, 18 Nov 2023 00:00:00 +000
The Pecten Oculi: An Enigma in Comparative Ophthalmology
- Authors: Amund Ringvold
  Abstract: Purpose: To summarize and evaluate the latest hypotheses on the function of the pecten oculi (PO). Methods: Review of relevant literature. Results: The PO is an organ present in all avian eyes. A similar structure, the conus papillaris (CP), is also found in terrestrial reptiles. Several reports have claimed the PO nourishes the avascular avian retina, but it has also been argued that the function is not primarily nutritive but instead may be related to intraocular pH-regulation, as the avian retina has an anaerobic metabolism. These conclusions are, at first glance, contradictory. However, a recent report indicated how these two views may be incorporated in a new and unifying hypothesis, with the common denominator being that the CP/PO evolved in tandem with increasing uric acid (UA) in serum. Discussion: According to Wingstrand and Munk, the PO leaks oxygen and nutrients to the retina, meaning that leakage of the small and heavily soluble component UA in serum could follow the same path. Protein-binding of the UA is not an option in the vitreous body, as the UA could crystalize intraocularly and harm the visual function. Two mechanisms countering this situation have been identified: 1) The inflow of the UA to the intraocular compartments (i. e. - vitreous body and anterior chamber) is reduced through selective barriers both in the PO and in the ciliary body. 2) The UA solubility is increased through alkalization of the vitreous body by the PO. Conclusion: During evolution vision was improved when the retinal vessels were collected in the PO. Two competing hypotheses on the PO’s function have been summarized, and it is shown how these may be incorporated in a new unifying hypothesis.
  PubDate: Sat, 18 Nov 2023 00:00:00 +000
Heterosis of Yield and Quality Traits of Watermelon [Citrullus lanatus
var. lanatus (Thunb.)] Hybrids and Their Performance in the Sub-Tropical
Region
- Authors: A K M Quamruzzaman; Limu Akter, M M R Salim, Ferdouse Islam
  Abstract: A study was conducted in watermelon to estimate the magnitude of heterosis for yield and its nine yield-related components. Sixteen hybrids generated from eight diverged parents were evaluated in a Randomized Block Design with three replications at the Olericulture Division, Horticulture Research Center (HRC), Bangladesh Agricultural Research Institute (BARI), Gazipur, Bangladesh. Appreciable heterosis was found over better parents for all the traits studied in a desirable direction. The range of positive better parent heterosis for a number of fruits/plant and individual fruit weight was 4.50 to 30.56 percent and 7.17 to 21.05 percent, respectively, while for fruit length and fruit diameter, it was 0.63 to 11.47 percent and 2.74 to 14.40 percent, respectively. Nine hybrids showed significant positive heterotic response for TSS, while twelve hybrids for fruit yield showed positive better parent heterosis and the range was 9.38 to 51.17 %. The higher significant positive better parent heterosis was observed in hybrids F1 104 (51.17%), F1 105 (44.30%), F1 801 (29.45%), F1 102 (23.38%), F1 401 (19.74%), F1 103 (19.14%). Considering yield contributing characters, the hybrids viz., F1 102, F1 104, F1 105, F1 801 were found promising and may be recommended for hybrid watermelon variety for the farmers of sub-tropical countries.
  PubDate: Sat, 18 Nov 2023 00:00:00 +000
Existence of positive periodic oscillation for a competitive-cooperative
model with feedback controls
- Authors: Chunhua Feng
  Abstract: In this paper, a class of nonlinear competitive-cooperative modes with feedback controls is considered. By employing the mathematical analysis method, two sufficient conditions for the existence of positive periodic solutions are obtained. Computer simulation is provided to verify the criteria. From the simulation, we see that time delays affect the oscillatory frequency
  PubDate: Sun, 12 Nov 2023 00:00:00 +000
Ameliorating the Effects of Phytochemical Substances on the Setting of
Cement with Rice Bran in the Production of Particle Boards Using a Natural
Accelerator
- Authors: Olaoluwa Ayobami Ogunkunle; Sunday Emmanuel Olajide
  Abstract: This research work evaluated the various means and alternatives that could be devised to improve the compatibility between rice bran and cement. Phytochemicals referred to as inhibitory substances, present in rice bran hinders its compatibility with cement via the means of compatibility factor obtained. The various ways that were looked into include the hot water treatment extraction process which reduced the intensity of water-soluble phytochemicals to an acceptable level and the addition of chemical additives. More so, cow horn (natural accelerator) - an appropriate naturally occurring calcium (Ca) source which is a cheap and effective substitute for the chemical additives was employed in improving compatibility factor. The existence and the extent of bonding in rice bran-cement bonded composites were also looked into. In order to compare the extent of compatibility, varying concentrations of chemical additives such as CaCl2, FeCl3, SnCl2 and SnCl4 were used with cow horn. These chemical additives act as accelerator as they decrease setting time. Thus, accelerating hydration reaction between the mineral binder used which is Portland cement and the rice bran.
  PubDate: Sun, 12 Nov 2023 00:00:00 +000
A Clinical Case Report: Artery-Veins Congenital Malformation
- Authors: Amelia Buque; Rameez Hussain
  Abstract: Aim: To report a clinical case of 10 years old girl, with low visual acuity in her right eye. Methods: This case report is a retrospective and descriptive study. Data was gathered from patient clinical record file that included anamnesis, examination and analysis of diagnostic tests. Results: A 10 years old female complains of headache, blurry visual acuity in her right eye (RE), for the last two weeks, before consultation. Uncorrected visual acuity RE was 6/9 and 6/6 in the left. Best corrected vision 6/6 for the both eyes. Both eyes anterior segment examination was normal. Right eye posterior segment exam revealed optical disc, tortuous artery-veins. The posterior segment of the left eye reveled normal. The OCT (Optical Coherence tomography) angiography showed dilated and tortuous vessels visible. Left eye OCT angiography reveled normal. The brain magnetic resonance imaging did not reveal any other arteriovenous malformation. Conclusion: On dilated fundus examination, a 10-year-old girl’s right eye revealed markedly dilated and tortuous vessels arising from the disc suggestive of Wyburn-Mason Syndrome of the right eye. This is a rare
  PubDate: Sun, 12 Nov 2023 00:00:00 +000
The Forming Analysis of SCM440 Alloy Steel Hexagon Head Flange Bolts
- Authors: Chih-Cheng Yang; Hong Quy Nguyen, Kuo-Hsiang Wang
  Abstract: In this study, a multi-stage cold forming process for the manufacture of hexagon head flange bolts is studied numerically with SCM440 alloy steel. The cold forming process through five stages includes forward extrusion, two upsetting operations, hexagonal trimming and circular trimming. The numerical study of cold forming is conducted using the code of DEFORM-3D. The formability of the workpiece is studied, such as the effect on forming force responses, maximum forming forces, effective stress and strain distributions and metal flow pattern. In the five-stage forming process, in the two upsetting and one hexagonal trimming forming stages, the effective stresses in the head of the workpiece are significantly high, and the effective strains are also significantly high due to large deformation. The flow line distributions are also very complex in which the flow lines in the trimming region of the upset head are severely bent, highly compacted, and eventually fractured due to excessive trimming. For the maximum axial forming force, the fourth stage, which the head of the workpiece is heavily trimmed into a thick hexagonal shape, is 1,360.4kN which is the largest among the five stages due to the large amount of trimming. However, for the forming energy, the second stage, which the workpiece is upset into a conical shape, is 9,841.0J which is the largest among the five stages due to longer acted axial forming stroke. The total maximum axial forming forces from the first to the last stages are 3,608.8kN and the total forming energies are about 26.16kJ.
  PubDate: Sun, 05 Nov 2023 00:00:00 +000
Characterization of the Calibration Results of Glass Electrode pH-meters
using Buffer Solutions Certified by Different Producers
- Authors: Adel B. Shehata; Abdurrahman R. AlAskar, Rashed A. Aldosari, Fahad R. AlMutairi
  Abstract: The buffer solutions of pH 4, 7 and 10 are very important certified reference materials in determining the accuracy of pH-meters with glass electrodes. The Saudi SASO/NMCC has certified a set of buffer solutions and their performance in the calibration of pH-meters has been verified with regard to the calibration results by three sets of buffer solutions certified by the Slovak SMU. The strength of traceability, bias, residuals, variance and regression of the calibration results have been characterized in order to evaluate the extent of performance agreement of the buffers from the two producing NMIs. The calibration results of four pH-meters by the four sets of buffer solutions fulfilled the traceability criterion and showed no bias. The regression analysis of the means of pH4, 7 and 10 values revealed that there is no significant difference between these means. Details of these evaluations are described in this article.
  PubDate: Sun, 05 Nov 2023 00:00:00 +000
Dynamic Response of Ductile Materials from Split Hopkinson Tension Bar
Tests
- Authors: Yehuda Partom; A. Lindenfeld
  Abstract: We use a SHTB (= Split Hopkinson Tension Bar) system to test the response of aluminum 6061-T651 samples under dynamic tension, and to calibrate a strength model for them. Interpretation of SHTB tests cannot be done with the so-called classical analysis, because: 1) the samples are long (relative to compression samples) and are not in dynamic equilibrium; 2) a neck is usually formed towards the end of the test; and 3) the strain to failure is quite high (around 50%). We therefore interpret the tests (calibrating from them a strength model and validating it), using computer simulations of the entire test system. Our entire system simulations are able to reproduce with good fidelity: 1) the response of the SHTB gauges on the two bars; 2) the time evolution, shape and location of the neck; and 3) the strain to failure measured after the test.
  PubDate: Sun, 05 Nov 2023 00:00:00 +000