American Scientific Research Journal for Engineering, Technology, and Sciences (ASRJETS)
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A High-Precision and Low-Cost Dew Point Equipment with Fuzzy Control System
Get PDFThe control of environmental conditions in some sectors of the industry is essential since the variation of these parameters can influence the quality of the manufactured product. For this, it is necessary to use measuring equipment with high precision, and when referring to the measurement of relative humidity, the dew point meter is indispensable. The chilled mirror method for measure °Cdp is the one of the most accurate that exists in the market, but these devices typically are high cost, hampering access to small businesses. The chilled mirror method basically consists of a PID (Proportional Integral Derivative) control of the temperature of a Peltier module based on the reading of the light intensity generated from the reflection of a light source. In this context, the proposal of this work is to develop a high precision and low cost device, operating in the range of -20 to 20°Cdp, replacing the traditional PID control by a Fuzzy control system, providing better accuracy in control, thus making a viable product mainly for small and medium-sized companies. The results presented show the feasibility of the proposal of this work, obtaining 98.9% accurate readings when compared with a reference equipment, and a maximum deviation observed was of 0.02°Cdp, thus proving its precision. Another point to note is the low cost of the equipment, approximately US$ 120.00, thus reaching the proposed objective
Application of Quality by Design in a Commercialized Lyophilized Vaccine
Get PDFThe pharmaceutical industry has being implementing regulatory practices to assure that consumers obtain products with quality, safety, and efficacy. The use of Quality by Design (QbD) for products on development has increased though the years to avoid issues related to quality parameters and has been suggested by Regulatory Agencies to standardize globally the documentation for the registration of new products. Although the concepts of QbD gain importance, it is still not a widespread practice to existing systems and products already on the market. This work aims to propose a case study with a vaccine using QbD concepts on the lyophilization unit operation production step to provide robustness and increase efficiency, leading to a lyophilization cycle time reduction. To this end, a reverse way of the use of QbD principles were applied based on historical batches database, down scale experiments, and finally in industrial scale to establish new boundaries in the lyophilization cycle. Experimental batches samples were analyzed through accelerated and real time stability study. At the end, this case became a possibility to establish new ranges to lyophilization process predicting risks and assure robustness to this production step with the maintenance of quality and safety of vaccine
BER Performance Enhancement of MIMO Systems Using Hybrid Detection Techniques Based on Sphere Decoding
Get PDFMIMO system is used in new communication systems to improve the bit error rate (BER), capacity, and the co-channel interference. In this paper, new hybrid detection techniques based on a combination between the sphere decoder (SD) and linear/non-linear detection techniques such as zero forcing (ZF), minimum mean square error (MMSE), Vertical Bell Lab Layered Space Time (V-BLAST), and lattice reduction are introduced. These hybrid techniques are intended to improve the BER performance of MIMO system. The proposed techniques are mainly based on dividing the received signal matrix into two equal size halves. The first half of the received symbols is detected using the selected linear or non-linear detector and the second half is detected using SD as the first scenario. For the second scenario, the first half of the received symbols is detected using SD and the second half is detected using the selected linear or non-linear detector. Several simulations are carried out to verify the efficiency of the proposed techniques. The simulations results show that the proposed techniques provide better performance than the traditional ones
Analysis of Environmental Pollution in Developing Countries
Get PDFEnvironmental pollution is a major concern in developing countries of the world, especially in Nigeria. This issue of pollution is a terrible negative vibe or influence on all the living things and the environment. Pollution of the environment via air, land and water by human activities is detrimental to the existence of all living things within the society which is not an acceptable development at all. Air pollution is caused by several factors such as emission from motor vehicles, industrial activities, volcanic eruption, emitting poisonous, forest fire, deforestation, bush burning and cosmic clouds of dusts. Soil pollution is also caused by factors such as oil spillage, human erosion and contamination by hazardous substances. Water pollution is caused by oil discharge from vessels, dumping from ships and aircrafts, wastes disposal from land, oil spillage, organic sources and other means of polluting the environment. Pollution is a vital environmental disaster due to the fact that some known and unknown diseases are discovered and might be difficult to subdue. In this article, environmental pollution will be discussed under three classes of pollution that is the water, the soil, and the air and their impact on human health; also needed measures to reduce pollution in Nigeria as a case study
Consumer-Related Corporate Social Responsibility and Brand Switching Behaviour of Subscribers of Mobile Network Providers in Akure Metropolis, Ondo State, Nigeria
Get PDFIn Nigeria, mobile telecom subscribers have suffered untold hardship in terms of poor service quality they receive from their service operators. These are often reflected in the deluge of complaints received by the National Communications Commission (NCC) which include: unsolicited promotion messages, outright truncated calls, mediocre data services, opaque charges, poor audio quality and lines joining, among other complaints. This has made switching a common phenomenon among subscribers of network providers in the Nigeria telecommunications industry. The study examined customer-related corporate social responsibility (CSR) and other factors influencing brand switching behaviour of subscribers of network providers in Akure metropolis, Ondo State, Nigeria. The population of the study consisted subscribers in Akure metropolis, Ondo State, Nigeria. Primary data was the major source of data collection for the study. Convenience and cluster sampling techniques were adopted to select Five Banks from Akure metropolis while a well structured questionnaire was designed to elicit responses from both staff and customers of the selected Banks.
A total of 230 copies of questionnaire were designed and administered on the staff and some customers of the selected banks who were subscribers of four major network providers – MTN, GLO mobile, Airtel and Etisalat, in Akure, metropolis. Descriptive statistics and Logistic Regression model were the techniques used to analyze the data collected. Findings of the study revealed that consumer-related CSR, network signal quality, fair pricing/call charges and promotional startegies have statistical significant effect on the switching behaviour of the customers. The study concluded that customer-related CSR, network signal quality, Fair pricing/Call charges and promotional strategy significantly influence the consumers to switch from one mobile line to another. The study recommended that customer-related CSR should be embraced by the network providers while also embarking on aggressive promotional strategies such as provision of offers and discounts, free data bundle, airtime bonus and so on, at regular interval to target those who influence consumers to switch their networks from one to another, most especially, relatives and friends so as to enhance profitability of their ventures.
Brain Cancer Detection Using U-Shaped Slot VIVALDI Antenna and Confocal Radar Based Microwave Imaging Algorithm
Get PDFVIVALDI antenna has been designed to work at frequency band [2.33-7.09] GHz with a maximum gain of 6.62dB. The antenna performance has been improved by creating a U-shaped slot on the upper layer of the antenna. etching U shape slot provides an improvement of 35.28% in return loss, 2.7% in bandwidth and 10% in gain. Spherical head phantom which consists of four layers whose dielectric properties have been compatible with their natural values has been designed by CST package to test the efficiency of antenna in the microwave imaging systems .1g average speci?c absorption rate (SAR) values has been measured in case the human brain without tumor and achieved international healthy standards. After that, it has been measured the value of SAR in case the human brain with tumor and observed that SAR value increased. Finally, monostatic radar-based confocal microwave imaging algorithm has been used to reconstruct image which appeared tumor location inside the head phantom. MATLAB software has been used to process data that obtained by CST package and generate the tumor image
Effectiveness Test of Robusta Coffee (Coffea cenephora) Extract from North Sumatra in Collagen and Hydration Skin Level of Female Wistar Rattus norvegicus
Get PDFRobusta coffee (Coffea canephora) is one of the Indonesian plants that have antioxidant compounds that can be used as cosmetic ingredients. The antiaging effect of the coffee extract can overcome the photoaging problem. The purpose of this study is to see the anti-aging effects of robusta coffee bean extract based on concentration variations of the female white rats. The study was conducted in a laboratory with pre and post control group design, from February to March 2019. 30 female white rats were divided into 5 groups and were sunbathed for 5 days, then were shaved 2x2 cm wide on the back and were given Robusta coffee bean extract cream 2.5%, 5%, 7.5%, 10%, and control. Applying cream twice a day for 4 weeks and changes were measured every 1 week for 4 weeks with a skin analyzer. The results were tested for the normality with the Shapiro-Wilk test and Levene\u27s test. Then followed by Anova Repeated, Pearson Correlation and Multiple Linear Regression test. Data analysis was using SPSS 21.0. There were the highest increased of collagen and hydration levels with Coffea canephora 10% extract given, and variable concentrations and duration of administration have a positive effect. The highest increased of collagen level was in the Coffea canephora 10% extract with an average 91.3% and hydration level amounted to 86.09%
Absolute Measurements for Uranium Verification Content in Radiographic Containers
Get PDFDepleted Uranium (DU) is used for its very high density in civilian uses include radiation shielding in medical radiation therapy, industrial radiography equipment, containers used to transport radioactive materials. Absolute measurements have been performed for verification of uranium mass content in gamma radiography by using detector’s model developed with MCNP in nuclear safeguard inspection for these samples. Both the experimental results obtained as well as MCNP results are used to estimate the 238U mass content. The determined and the declared 238U masses values are found in an agreement with accuracy from -1.74 % to 1.80 %
Unusual Presentation of the Intracranial Arachnoid Cysts Posing with Treatment Dilemma: A Case Series
Get PDFA case series comprising of 3 patients with intracranial arachnoid cysts presented with atypical features raising the doubt on the symptomatic nature of the cyst. It posed dilemma on the further management of these patients. In two patients, surgical intervention to decompress the arachnoid cyst was performed which drastically improved the patient’s symptoms. One patient with intracranial arachnoid cyst who has been conservatively managed persists to have symptoms
Estimation of Flame Temperature and Alkali Emission During the Combustion of Sugarcane Bagasse in Laboratory in Combustion Chamber Type Grate Using Spectroscopy Method
Get PDF Knowing the temperature of the combustion of solid biomass residues and how alkaline gases must be supplied during combustion is an area currently under study in the international community. The correlation between temperature and concentration of alkaline gases in the combustion phases is an open research for some types of biomass, among which sugarcane bagasse. This information optimizes the operation of thermoelectric boilers that use solid biomass waste as fuel, improving its efficiency and maintenance costs. The aim of the study was to estimate the temperature of the flame during the combustion of sugarcane bagasse in a pilot chamber that simulates burning in a grid, as well as an estimate of the potassium concentration in the flue gases. Temperature estimates were made using the two-color spectrometry technique in the visible light range. The potassium concentrations in the flue gases were estimated through analysis of the emission lines present in the electromagnetic spectra collected by a spectrometer for different combustion temperatures. In the experiments, the biomass flame was of the diffusion flame type. Considered the combustion phases - devolatilization, char combustion and ash formation - temperature were varying in the range of 1000 K to 1700 K. The average emission of potassium in the flue gases was evaluated in the range of 0.126 ppm to 0.631 ppm, considering the combustion phases. For the combustion conditions, no alkaline sodium gases were detected