Energy, exergy and efficiency analysis of a flat plate solar collector used as air heater

Air heating by solar collectors is renewable technology providing hot air for different purposes. The present research emphasizes on analysis of energy, exergy and efficiency of a flat plate solar air heater. The analysis model was tested on five different air mass flow rates of 0.5 (Natural), 1.31, 2.11, 2.72 and 3.03 kgs-1 under three different tilt angles of 25, 35 (Recommended) and 50o. The data was replicated three times making a total of 45 treatments. A two factorial completely randomized design was used to find if there is any significant difference among the treatments. The results showed that the solar collector gave better performance at air mass flow of 3.03 kgs-1 under tilt of 35o. At maximum air mass flow rate of 3.03 kgs-1and optimum tilt angle of 35o the maximum energetic efficiency of 51%, while minimum exergetic efficiency of 24% and maximum overall efficiency of 71% were recorded. It was concluded that to get maximum thermal efficiencies of 71% from flat plate solar collector used as an air heater must be operated at high air mass flow rates of 3.03 kgs-1under 35o tilt angle at Peshawar, Pakistan

Effects of temperature and water purity on germination and yield of mungbean sprouts

Mungbean (Vigna radiata L. Wilczek) is a popular pulse crop, producing protein-rich food and nitrogen-rich residues. Mungbean sprouts were grown at different temperature levels of 10, 20 and 30°C in various water purities of 30 (distilled water), 100, 400, 700 and 1000 TDS (ppm). After keeping them in the germination chamber for 72 h, the percentage of germination, stem length and yield along with proximate composition were determined. The temperature was kept as main factor and water purity as the second. The experiment was replicated four times and the data obtained were analyzed using two factorial completely randomized design. The results showed that both the factors had significant (p<0.05) effect on the germination, stem length, yield as well as proximate composition. A temperature of 30°C and water with high purity of 30 TDS resulted in high emergence (69%), stem length (3.14 cm) and yield (70.1 g) as compared to the other treatments. Minimum germination (2.1%), stem length (0.11 cm) and yield (12.11 g) were recorded in samples kept at low temperature of 10°C and water purity with 1000 TDS. The mungbean seeds showed a very low plasticity to water purity, and that they were very susceptible to water impurities. It is concluded that, to prepare sprouts from mungbeans, it is necessary to germinate mungbean seeds them in water having high purity and temperature of 30oC for maximum germination, stem length and yield

An Efficient Classification of Emotions in Students\u27 Feedback using Deep Neural Network

Background and Objective: In both the corporate and academic worlds, the collection and analysis of feedback (product evaluation, social media debate, and student input) has long been a significant topic. The traditional approaches to collect student feedback focused on data collection and analysis via questionnaires. However, the student makes comments on social media sites that need to be looked at to improve educational standards at schools.Methods: The purpose of this work is to construct a deep neural network-based system to assess students\u27 feedback and emotions found in the reviews. Our approach applies a Deep Learning-based Bi-LSTM Model to a benchmark student input dataset. It would categorize students\u27 feedback about their instructors according to their emotional states, such as love, happiness, fury, and disdain.Results: The experimental findings demonstrate that the proposed approach outperforms both benchmark studies and state-of-the-art machine learning classifiers

Phenological and yield components response of major exotic maize varieties to different levels of soil bulk densities

Maize is the second staple food and a major cereal crop in Pakistan, but its actual yield is 25-30% less than the potential because of high soil bulk densities. Three exotic maize varieties (Baber, Pioneer-30P45, and Syngenta-6621) were evaluated under the three different soil bulk densities of 1.00 - 1.30, 1.30 - 1.60, and 1.60- 1.90 g.cm-3. Nine treatments were replicated three times, making 27 pots experiments under complete randomized design were tested. Results showed that bulk density significantly (α < 0.05) affected all the parameters of the crops except the number of days to emergence. The fewest number of days to emergence (8.4), tasseling (60.9), silking (66.9), maturity (91.9), leaves per plant (6.3), as well as the lowest shoot thickness (0.49 cm) were obtained under the 1.00 - 1.30 g.cm-3 density. This density also produced the tallest plants (174.7 cm), highest stover (5938.7 kg ha-1), grain yields (1551 kg ha-1), and harvest index (21.9 %). Conversely, most days to emergence, tasseling, silking, and maturity occurred at the bulk density of 1.60 - 1.90 g.cm-3, which also produced the shortest plants and the lowest grain stover and grain yields as well as the harvest index. It was concluded that increasing bulk density levels increase the number of days to tasseling, silking, maturity, and leaves per plant and shoot thickness. Syngenta 6621 was found late in maturity among the hybrids but produced superior stover and grain yields

Awareness and perceptions of electroconvulsive therapy among psychiatric patients: a cross-sectional survey from teaching hospitals in Karachi, Pakistan

<p>Abstract</p> <p>Background</p> <p>Electroconvulsive therapy (ECT) is shown to be effective in many psychiatric illnesses, but its distorted projection by the Pakistani media and its unregulated use by many physicians across the country have adversely affected its acceptability. Given this situation we aimed to assess the awareness and perceptions regarding ECT as a treatment modality among the psychiatric patients.</p> <p>Methods</p> <p>This was a questionnaire based cross-sectional study carried out at 2 tertiary care hospitals in Karachi, Pakistan.</p> <p>Results</p> <p>We interviewed 190 patients of which 140 were aware of ECT. The study showed that the level of education had a significant impact on the awareness of ECT (p = 0.009). The most common source of awareness was electronic and print media (38%), followed by relatives (24%) and doctors (23%). Physical injuries (42%) and neurological (12%) and cognitive disturbances (11%) were the commonly feared side effects. The most popular belief about ECT was that it was a treatment of last resort (56%). Thirty-nine percent thought that ECT could lead to severe mental and physical illness and 37% considered it inhumane. Patients' willingness to receive ECT was dependant on whether or not they were convinced of its safety (p = 0.001) and efficacy (p = 0.0001).</p> <p>Conclusion</p> <p>We identified a serious lack of dissemination of information regarding ECT by the psychiatrists and the mental health care providers. This may be the result of an inadequate postgraduate training in Pakistan or just a lack of concern about the mentally ill patients. The media seemed to be the major source of information for our patients. We also saw the prevalence of a variety of myths regarding ECT in our society, which we feel may be responsible for the patients' adverse attitudes. Given the widespread applicability of ECT there is a dire need to dispel these misconceptions and improve its acceptability.</p

The impact of immediate breast reconstruction on the time to delivery of adjuvant therapy: the iBRA-2 study

Background: Immediate breast reconstruction (IBR) is routinely offered to improve quality-of-life for women requiring mastectomy, but there are concerns that more complex surgery may delay adjuvant oncological treatments and compromise long-term outcomes. High-quality evidence is lacking. The iBRA-2 study aimed to investigate the impact of IBR on time to adjuvant therapy. Methods: Consecutive women undergoing mastectomy ± IBR for breast cancer July–December, 2016 were included. Patient demographics, operative, oncological and complication data were collected. Time from last definitive cancer surgery to first adjuvant treatment for patients undergoing mastectomy ± IBR were compared and risk factors associated with delays explored. Results: A total of 2540 patients were recruited from 76 centres; 1008 (39.7%) underwent IBR (implant-only [n = 675, 26.6%]; pedicled flaps [n = 105,4.1%] and free-flaps [n = 228, 8.9%]). Complications requiring re-admission or re-operation were significantly more common in patients undergoing IBR than those receiving mastectomy. Adjuvant chemotherapy or radiotherapy was required by 1235 (48.6%) patients. No clinically significant differences were seen in time to adjuvant therapy between patient groups but major complications irrespective of surgery received were significantly associated with treatment delays. Conclusions: IBR does not result in clinically significant delays to adjuvant therapy, but post-operative complications are associated with treatment delays. Strategies to minimise complications, including careful patient selection, are required to improve outcomes for patients

Data-Based Sensing and Stochastic Analysis of Biodiesel Production Process

Biodiesel production is a field of outstanding prospects due to the renewable nature of its feedstock and little to no overall CO2 emissions to the environment. Data-based soft sensors are used in realizing stable and efficient operation of biodiesel production. However, the conventional data-based soft sensors cannot grasp the effect of process uncertainty on the process outcomes. In this study, a framework of data-based soft sensors was developed using ensemble learning method, i.e., boosting, for prediction of composition, quantity, and quality of product, i.e., fatty acid methyl esters (FAME), in biodiesel production process from vegetable oil. The ensemble learning method was integrated with the polynomial chaos expansion (PCE) method to quantify the effect of uncertainties in process variables on the target outcomes. The proposed modeling framework is highly accurate in prediction of the target outcomes and quantification of the effect of process uncertainty

A Conceptual Model of Factors Influencing Customer Relationship Management in Global Software Development: A Client Perspective

The software development industry or organizations increasingly emerging day by day have adopted global software development (GSD) practices due to the large significance of outsourcing. These industries face many challenges due to a lack of understanding customer perspective in the GSD environment. For any organization, the customer is the major stakeholder, and customer relationship management (CRM) plays a vital role in customer satisfaction with software development projects. These challenges create serious risks for any software development project’s success. Thus, CRM is a crucial challenge in the success of software projects in the GSD environment. This research study aims to address the factors that negatively influence CRM implementation in the global context and proposes a conceptual model based on the identified factors for enhancing software product quality. The systematic literature review (SLR) phase investigates the potential barriers to CRM implementation in GSD. Based on identified barriers, an initial conceptual model is developed. The proposed conceptual model is validated using a questionnaire survey of the GSD industry and CRM practitioners of Pakistan. Statistical analysis and several suitable tests are also performed to develop the final conceptual model for CRM implementation in the GSD environment. This research is performed from the client’s perspective. The results are promising and accommodating to avoid any software project failure due to customer-related issues in a GSD environment

Fabrication of MNPs/rGO/PMMA Composite for the Removal of Hazardous Cr(VI) from Tannery Wastewater through Batch and Continuous Mode Adsorption

Herein, we report the synthesis of magnetic nanoparticle (MNP)-reduced graphene oxide (rGO) and polymethylmethacrylate (PMMA) composite (MNPs/rGO/PMMA) as adsorbent via an in situ fabrication strategy and, in turn, the application for adsorptive removal and recovery of Cr(VI) from tannery wastewater. The composite material was characterized via XRD, FTIR and SEM analyses. Under batch mode experiments, the composite achieved maximum adsorption of the Cr(VI) ion (99.53 ± 1.4%, i.e., 1636.49 mg of Cr(VI)/150 mg of adsorbent) at pH 2, adsorbent dose of 150 mg/10 mL of solution and 30 min of contact time. The adsorption process was endothermic, feasible and spontaneous and followed a pseudo-2nd order kinetic model. The Cr ions were completely desorbed (99.32 ± 2%) from the composite using 30 mL of NaOH solution (2M); hence, the composite exhibited high efficiency for five consecutive cycles without prominent loss in activity. The adsorbent was washed with distilled water and diluted HCl (0.1M), then dried under vacuum at 60 °C for reuse. The XRD analysis confirmed the synthesis and incorporation of magnetic iron oxide at 2θ of 30.38°, 35.5°, 43.22° and 57.36°, respectively, and graphene oxide (GO) at 25.5°. The FTIR analysids revealed that the composite retained the configurations of the individual components, whereas the SEM analysis indicated that the magnetic Fe3O4–NPs (MNPs) dispersed on the surface of the PMMA/rGO sheets. To anticipate the behavior of breakthrough, the Thomas and Yoon–Nelson models were applied to fixed-bed column data, which indicated good agreement with the experimental data. This study evaluates useful reference information for designing a cost-effective and easy-to-use adsorbent for the efficient removal of Cr(VI) from wastewater. Therefore, it can be envisioned as an alternative approach for a variety of unexplored industrial-level operations

Multiaccess Edge Computing Empowered Flying Ad Hoc Networks with Secure Deployment Using Identity-Based Generalized Signcryption

A group of small UAVs can synergize to form a flying ad hoc network (FANET). The small UAVs are, typically, prone to security lapses because of limited onboard power, restricted computing ability, insufficient bandwidth, etc. Such limitations hinder the applicability of standard cryptographic techniques. Thus, assuring confidentiality and authentication on part of small UAV remains a far-fetched goal. We aim to address such an issue by proposing an identity-based generalized signcryption scheme. The lightweight security scheme employs multiaccess edge computing (MEC) whereby the primary UAV, as a MEC node, provides offloading to the computationally fragile member UAVs. The scheme is based on the concept of the hyperelliptic curve (HEC), which is characterized by a smaller key size and is, therefore, suitable for small UAVs. The scheme is robust since it offers confidentiality and authentication simultaneously as well as singly. Formal as well as informal security analyses and the validation results, using the Automated Validation for Internet Security Validation and Application (AVISPA) tool, second such notion. Comparative analysis with the existing schemes further authenticates the sturdiness of the proposed scheme. As a case study, the scheme is applied for monitoring crops in an agricultural field. It has been found out that the scheme promises higher security and incurs lower computational and communication costs