52 research outputs found
Descriptive statistics for ball bearings data.
No full textGul and Mohsin 2021 developed a new modified form of renowned “Half logistic” distribution introduced by Balakrishnan (1991) and named it half logistic-truncated exponential distribution (HL-TEXPD). Some mathematical characteristics are studied, including hazard function, Pth percentile, moment generating function and Shannon entropy. Simulation study is performed to examine the behaviour of parameter estimates. The proposed model is fitted on three real data sets to check its efficacy. Additionally, TTT (total time on test) plot is drawn to study the failure rate of the three data sets. The results verdict that HL-TEXPD can be efficiently utilized in the field of engineering and medical sciences based on the data sets under study contrary to the classical and baseline models.</div
Modeling Approach to Estimate Energy Consumption of Reverse Osmosis and forward Osmosis Membrane Separation Processes for Seawater Desalination
No full textDue to growing industrialization and population increase, water scarcity is becoming a major global concern. Desalination is often regarded as a potential solution to the worldwide water crisis; however, due to rising prices and energy usage, desalination has remained a research focus. Traditionally, specific energy consumption (SEC) kWh/m3 for seawater desalination has been calculated using a hybrid approach that ignores membrane design attributes and operational parameters. The current study constructed a mathematical framework based on well-established theory to quantify and compare the energy consumption of pressure-driven and osmotic-driven membrane separation processes by incorporating the necessary membrane design and operational parameters into the model framework. The model results were compared to the literature data and found to be in good agreement. The findings of this study show a non-linear relationship between the membrane flowrate factor and the energy needs of reverse osmosis RO, with the effect being more obvious at low values of Kf < 50 L/h.bar, where Kf is equal to the product of membrane permeability and membrane area. The results also showed that the lowest SEC was obtained at 60–65% recovery, and, from model testing, the energy consumption was 3.65 kWh/m3 and 3.88 kWh/m3 for the RO and FO–RO processes, respectively. Additionally, the hybrid process demands more membrane area, which further raises the cost of desalination. The mathematical framework developed in this work will act as a prediction design tool for membrane plant designers to check and compare the feasibility of these processes before experimental work to save money and time
Precoding in MIMO, OFDM to reduce PAPR (Peak to Average Power Ratio)
No full textOne of the critical issues of systems utilizing Orthogonal Frequency Division Multiplexing (OFDM) is the high peak to the average power ratio of OFDM signals. We have used Precoding as a way to mitigate the PAPR problem. Furthermore the performance of Precoded OFDM in fading multi-path channels has been studied. This thesis is based on an efficient technique for reducing the PAPR of OFDM signals. The proposed technique is data-independent and thus, does not require new processing and optimization for each transmitted OFDM block. The reduction in PAPR of the OFDM signal is obtained through a proper selection of a Precoding scheme that distributes the power of each modulated symbol over the OFDM block. The obtained results show that this Precoding scheme is an attractive solution to the PAPR problem of OFDM signals
Precoding in MIMO, OFDM to reduce PAPR (Peak to Average Power Ratio)
No full textOne of the critical issues of systems utilizing Orthogonal Frequency Division Multiplexing (OFDM) is the high peak to the average power ratio of OFDM signals. We have used Precoding as a way to mitigate the PAPR problem. Furthermore the performance of Precoded OFDM in fading multi-path channels has been studied. This thesis is based on an efficient technique for reducing the PAPR of OFDM signals. The proposed technique is data-independent and thus, does not require new processing and optimization for each transmitted OFDM block. The reduction in PAPR of the OFDM signal is obtained through a proper selection of a Precoding scheme that distributes the power of each modulated symbol over the OFDM block. The obtained results show that this Precoding scheme is an attractive solution to the PAPR problem of OFDM signals
Multi-banking automatic teller machine transaction system by utilizing GSM and biometric identification with one single touch
No full textEveryone in many banks has many types of bank accounts, people need to bring a lot of ATM cards for their transaction, many
types of PINs for each account.In the current system, ATM machine user identification systems depend only on bank ATM car
ds, safety secret pin code, and also such kind of user ID verification methods which measures are not optimal and sometimes t
here are incidents where we dismiss our secret security PIN code, lose ATM cards, rob ATM cards, stolen secret PIN code.
Weare presenting a fresh concept or idea for the ATM machine user identification scheme, "Multi-banking Automatic Teller
Machine Transaction System by Utilizing GSM and Biometric Identification with One Single Touch" to get control of the
issues in the current ATM machine system. On the base of fingerprint identification method which is also one of most secure
systems, unofficial accesses are blocked, as it makes fingerprint technique a unique recognition for every user. Our introduced
system also assures a very secure GSM and OTP based transaction deals. The presented scheme has no hazard in managing
many account transaction deals and performs high-level security, compared to the current ATM machine scheme
Motion Synchronization Control for a Large Civil Aircraft’s Hybrid Actuation System Using Fuzzy Logic-Based Control Techniques
No full textThe motion synchronization of the hybrid actuation system (composed of a servo-hydraulic actuator and an electro-mechanical actuator) is very important for all applications, especially for civil aircraft. The current research presents a nested-loop control design technique to synchronize motion between two different actuators, such as a servo-hydraulic actuator (SHA) and an electro-mechanical actuator (EMA). The proposed strategy consists of a trajectory, an intelligent position controller (fuzzy logic-based controller), a feed-forward controller, and an intelligent force controller (fuzzy logic-based controller). Position, speed, and acceleration signals are produced by trajectory at a frequency that both SHA and EMA can follow. The SHA/EMA system’s position tracking performance is enhanced by the feed-forward controller and intelligent position controller working together, while the intelligent force tracking controller lowers the issue of force fighting by focusing on the rigid coupling effect. To verify the effectiveness of the proposed strategy, simulations are performed in the Matlab/Simulink environment. The result shows that the proposed intelligent control strategy not only reduces initial force fighting, but also improves load-rejection performance and output-trajectory tracking performance
Multi-banking automatic teller machine transaction system by utilizing GSM and biometric identification with one single touch
No full textEveryone in many banks has many types of bank accounts, people need to bring a lot of ATM cards for their transaction, many types of PINs for each account. In the current system, ATM machine user identification systems depend only on bank ATM cards, safety secret pin code, and also such kind of user ID verification methods which measures are not optimal and sometimes there are incidents where we dismiss our secret security PIN code, lose ATM cards, rob ATM cards, stolen secret PIN code.
Weare presenting a fresh concept or idea for the ATM machine user identification scheme, "Multi-banking Automatic Teller Machine Transaction System by Utilizing GSM and Biometric Identification with One Single Touch" to get control of the issues in the current ATM machine system. On the base of the fingerprint identification method which is also one of the most secure systems, unofficial accesses are blocked, as it makes the fingerprint technique a unique recognition for every user. Our introduced system also assures a very secure GSM and OTP based transaction deals. The presented scheme has no hazard in managing many account transaction deals and performs high-level security, compared to the current ATM machine scheme
Heart valve surgery: EuroSCORE vs. EuroSCORE II vs. Society of Thoracic Surgeons score
No full textBackground
This is a validation study comparing the European System for Cardiac Operative Risk Evaluation (EuroSCORE) II with the previous additive (AES) and logistic EuroSCORE (LES) and the Society of Thoracic Surgeons’ (STS) risk prediction algorithm, for patients undergoing valve replacement with or without bypass in Pakistan.
Patients and Methods
Clinical data of 576 patients undergoing valve replacement surgery between 2006 and 2013 were retrospectively collected and individual expected risks of death were calculated by all four risk prediction algorithms. Performance of these risk algorithms was evaluated in terms of discrimination and calibration.
Results
There were 28 deaths (4.8%) among 576 patients, which was lower than the predicted mortality of 5.16%, 6.96% and 4.94% by AES, LES and EuroSCORE II but was higher than 2.13% predicted by STS scoring system. For single and double valve replacement procedures, EuroSCORE II was the best predictor of mortality with highest Hosmer and Lemmeshow test (H-L) p value (0.346 to 0.689) and area under the receiver operating characteristic (ROC) curve (0.637 to 0.898). For valve plus concomitant coronary artery bypass grafting (CABG) patients actual mortality was 1.88%. STS calculator came out to be the best predictor of mortality for this subgroup with H-L p value (0.480 to 0.884) and ROC (0.657 to 0.775).
Conclusions
For Pakistani population EuroSCORE II is an accurate predictor for individual operative risk in patients undergoing isolated valve surgery, whereas STS performs better in the valve plus CABG group
Nosocomial Transmission of SARS CoV-2 in a Tertiary Care Hospital in Peshawar, Pakistan
No full textObjective
The study aimed to determine the frequency of nosocomial transmission of severe acute respiratory syndrome coronavirus-2 (SARS CoV-2) in a tertiary care hospital in Peshawar, Pakistan.
Methodology
This cross sectional, analytical study was carried out in Hayatabad Medical Complex, Peshawar, Pakistan from 1st June 2021 to 31st August 2021. Consecutive patients aged 18 years and above admitted for conditions other than COVID-19 with a negative rapid antigen test for COVID-19 at admission were included. Patients with respiratory symptoms or those who were hospitalized for any reason in the preceding six weeks in any health care facility were excluded. The study protocol was completed by 90.9% of participants. The rapid antigen test was repeated for participants at the time of discharge or symptoms suggestive of COVID-19. Patients with a positive rapid antigen test for COVID-19 either at the time of discharge or symptom onset were considered to have acquired nosocomial SARS-CoV-2 infection. Statistical Package for the Social Sciences version 21 for Windows was used for data analysis.
Results
The frequency of nosocomial transmission of SARS-CoV-2 was 2.7% (13/482). Patients with nosocomial COVID-19 stayed longer in the hospital than those who tested negative (7.5±4.0 versus 4.8±3.6 days; p=0.006). Age (p=0.796), gender (p=0.453), department of inpatient stay (p=0.943), major surgery (p=0.678), minor surgery (p=0.576), and visit to the radiology department (p=0.707) did not affect nosocomial spread of SARS-CoV-2.
Conclusion
Nosocomial transmission of COVID-19 was infrequent, accounting for 2.7% of participants in this study
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