Transient Flow Features in the Vicinity of a Vertical Axis Wind Turbine

The increasing demand of energy in the world is driving the search for more renewable and sustainable energy sources. Renewable sources of energy are being explored globally to overcome the depletion of fossil fuels and the resulting energy crisis. Moreover, use of fossil fuels has significant negative effects on the environment. Therefore, the focus is currently on both to ensure long-term energy supply, as well as to monitor and minimise the negative effects of these sources on the environment. In order to meet renewable energy targets, harnessing energy from all available resources such as wind, (through wind turbine), is necessary. Wind energy is one of the important sources of renewable energy. Wind turbine technology has been developed continuously, but the maintenance of wind turbines is still a topic of interest. Horizontal axis wind turbines (HAWT) have dominated the wind energy and high power generation characteristics. However, vertical axis wind turbines (VAWT) are also gaining wide acceptance owing to being capable of producing power even at low speeds. The present study focuses on the quantification of the effect of steady wind flow conditions on the performance of Savonius type vertical axis wind turbine. The Savonius vertical axis wind turbine considered in this study comprises of multi-blade rotor and stationary inlet guide vanes, with the arrangement most suitable for a low wind speed application. Advanced numerical modeling tools within ANSYS–Fluent have been used in the present work to simulate the flow in and around the Savonius vertical wind turbine in order to quantify the flow behavior. Sliding mesh technique has been incorporated to simulate the rotation of the rotor blade, which capture the flow phenomenon caused by the stator and the rotor interaction, and hence providing more accurate results. A critical analysis of the flow across vertical axis wind turbine has been conducted through investigating the static pressure and velocity magnitude variations in the vicinity of the wind turbine. Furthermore, the present study has also focused on the performance of a vertical axis wind turbine under unsteady flow conditions whereby the flow is accelerated and decelerated as characterised by the change in the wind velocity. The torque and power generation capabilities of the turbine have been characterised and in particular the rotor contribution has been quantified. The effect of transient phenomena under varying torque outputs during accelerating and decelerating flows has also been highlighted. Overall performance of the turbine has also been quantified

FREQUENCY OF CAROTID ATHEROSCLEROSIS IN CEREBRAL INFARCTION

Objective: To know the frequency of carotid atherosclerosis in ischaemic stroke patients in our population using color Doppler ultrasound. Methodology: This is an observational study conducted in the department of Medicine Nishtar Hospital, Multan. All the patients admitted during this duration with CT scan proof of stroke were included in the study. Risk factors in all these patients were stratified. Doppler ultrasound was performed on all patients with ischaemic stroke according to the study protocol. Results: A total of 100 patients were included in this study over a period of five months. 66% of these were having cerebral infarction. Hypertension (72%), diabetes (35%), smoking (29%) and obesity (20%) were the common risk factors. The frequency of significant carotid atherosclerosis in acute ischaemic stroke patients was 21%. Conclusion: Carotid atherosclerosis is one of the most important indicators, predictors as well as an independent risk factor in the development of ischaemic stroke. KEY WORDS: Carotid, Atherosclerosis, Doppler ultrasound

EFFICACY OF INTRAVENOUS ACETAMINOPHEN VERSUS KETAMINE FOR POSTOPERATIVE PAIN AFTER ABDOMINAL HYSTERECTOMY

Objective; To determine the efficacy of intravenous acetaminophen versus ketamine for postoperative pain after abdominal hysterectomy. Material and Methods; A total of 114 women undergoing abdominal hysterectomy were taken in this study. The study was conducted from June 2017 to May 2018 at department of Anesthesiology, Nishtar Hospital, Multan. Results; Our study comprised of 114 ladies undergoing abdominal hysterectomy, mean age of the study cases was 54.13 ± 6.89 years (with minimum age of the patients was 39 years while maximum age was 68 years). Majority of our study cases i.e. 92 (80.7 %) had parity more than 3 and American Society of Anesthesiology (ASA) score level 1 in 93 (81.6%). Sixty one (53.1%) belonged to rural areas, while mean duration of surgery was 72.80 ± 11.32 minutes. Mean BMI level in our study cases was noted to be 23.98 ±4.17 Kg/m2 and obesity was present in 34 (29.8%) of our study cases. Efficacy was noted in 60 (52.6 %) of our study cases. Efficacy was 73.7% study cases in group A while 18 (31.6%) in group B (p=0.000). Conclusion; Our study results support the use of intravenous acetaminophen (IVA) for pain management in patients undergoing abdominal hysterectomy compared with ketamine. Intravenous acetaminophen is safe, reliable and effective for the pain management in postoperative abdominal hysterectomy patients which was associated with shorter hospital stay and cost effective for the suffering families. No adverse reactions were noted in this study with the use of intravenous acetaminophen. Keywords; Intravenous acetaminophen, Ketamine, Abdominal Hysterectomy.

A Single Machine Scheduling Problem with Individual Job Tardiness based Objectives

377-382A multi-objective scheduling problem with specified release times and due dates for individual tasks is analysed in this study. Distinct tardiness value of each task j comprises the part of the objective, while it is desired to identify all non-dominated solutions. Tardiness values for a total number of n tasks complete a single solution making it an n-objective scheduling problem. Tardiness is treated here as a task specific objective, being different in the usual scheduling context. A branch and bound procedure is proposed for individual tardiness of tasks in multi-objective contexts. The procedure is illustrated with an example. Active schedule enumeration scheme with depth-first strategy for branching is used in branching while two different bounding schemes are tested. However, an improved bounding scheme to find better-quality need to be developed. Procedure is found to perform well on small scale problems. For an n-objective problem like this, a more robust data structure may further improve the performance of the procedure

Enterprise Resource Planning (ERP) Implementation Issues: An Empirical Study in Commercial Banking Industry of Pakistan

In this modern era of digital technology and continuous changing global business environment, firms have no other choice rather persistently improve their capabilities and enhance their competitive advantages. To get this objective, many organizations are now focusing towards adoption of Enterprise Resource Planning (ERP) frameworks. An ERP system uses different sorts of data preparing abilities and place the accumulated information into a solitary database. Enterprise Resource Planning (ERP) systems are very complex integrated systems. ERP implementation is a tough, lengthy and expensive procedure for an organization who adopt it and most of time it leads to failure. In developing countries, the success rate of implementing ERP systems is extremely lower than that in western world. Thus, ERP implementation success is treated as dependent variable in this study, it used explanatory and predictive orientations. First, it identified the critical factor from past studies then explain the impact on the ERP implementation success in Pakistan banking sector context. Collected data was analyzed using SPSS. Finally, results and discussions were presented. Keywords: Enterprise resource planning (ERP), Manufacturing requirement planning, (MRP), centralized database, Information System, Management commitment

Development of a new detection algorithm to identify acute coronary syndrome using electrochemical biosensors for real-world long-term monitoring

Electrochemically based technologies are rapidly moving from the laboratory to bedside applications and wearable devices, like in the field of cardiovascular disease. Major efforts have focused on the biosensor component in contrast with those employed in creating more suitable detection algorithms for long-term real-world monitoring solutions. The calibration curve procedure presents major limitations in this context. The objective is to propose a new algorithm, compliant with current clinical guidelines, which can overcome these limitations and contribute to the development of trustworthy wearable or telemonitoring solutions for home-based care. A total of 123 samples of phosphate buffer solution were spiked with different concentrations of troponin, the gold standard method for the diagnosis of the acute coronary syndrome. These were classified as normal or abnormal according to established clinical cut-off values. Off-the-shelf screen-printed electrochemical sensors and cyclic voltammetry measurements (sweep between −1 and 1 V in a 5 mV step) was performed to characterize the changes on the surface of the biosensor and to measure the concentration of troponin in each sample. A logistic regression model was developed to accurately classify these samples as normal or abnormal. The model presents high predictive performance according to specificity (94%), sensitivity (92%), precision (92%), recall (92%), negative predictive value (94%) and F-score (92%). The area under the curve of the precision-recall curve is 97% and the positive and negative likelihood ratios are 16.38 and 0.082, respectively. Moreover, high discriminative power is observed from the discriminate odd ratio (201) and the Youden index (0.866) values. The promising performance of the proposed algorithm suggests its capability to overcome the limitations of the calibration curve procedure and therefore its suitability for the development of trustworthy home-based care solutions

Mapping Change in Spatial Extent and Density of Mangrove Forest at Karachi Coast Using Object Based Image Analysis

Karachi shoreline is more than 135 Km long significant for marine fishery breeding and spawning. During 2005 to 2018 the mangrove forest areas in Karachi increased in extent but declined in density. The main cause of mangrove cover change in this region are coastal region development (port building, industrial area and waterfront project). This study aims to monitor both extent and density changes of mangrove forest at Karachi coast. For this purpose, the Landsat imagery was used of the years 2005 and 2018 covering a span of 14 years. The imageries were processed through Normalized Difference Vegetation Index (NDVI) analysis. Simultaneously, random sample locations were identified for mapping and validation of mangrove forest extent and density during 2005 to 2018. The sample locations were categorized as dense, normal and sparse classes. In the next step, sample locations were plotted on NDVI images to determine mean, minimum and maximum values for each class of mangrove forest. In the final step, the accuracy assessment was done using Kappa statistics. Results show that overall accuracy of 2018 imagery is better than 2005 Landsat imagery. The overall extent of mangrove forest increased in the past years