Experimental Characterization of Electrical Discharge Machining of Aluminum 6061 T6 Alloy using Different Dielectrics

Electrical discharge machining is a non-traditional machining method broadly employed in industries for machining of parts that have typical profiles and require great accuracy. This paper investigates the effects of electrical parameters: pulse-on-time and current on three performance measures (material removal rate, microstructures and electrode wear rate), using distilled water and kerosene as dielectrics. A comparison between dielectrics for the machining of aluminum 6061 T6 alloy material in terms of performance measures was performed. Aluminum 6061 T6 alloy material was selected, because of its growing use in the automotive and aerospace industrial sectors. The experimental sequence was designed using Taguchi technique of L9 orthogonal array by changing three levels of pulse-on-time and current, and test runs were performed separately for each dielectric. The results obtained show that greater electrode wear rate (EWR) and higher material removal rate (MRR) were achieved with distilled water when compared with kerosene. These greater EWR and MRR responses can be attributed to the early breakage of the weak oxide and carbide layers formed on the tool and alloy material surfaces, respectively. The innovative contributions of this study include, but are not limited to, the possibility of machining of aluminum 6061 T6 alloy with graphite electrode to enhance machinability and fast cutting rate employing two different dielectrics.Peer reviewe

Increasing the use of dementia screening in the primary care setting

More than 5 million people have Alzheimer’s disease today and 450,000 people in the US die of Alzheimer’s every year. By 2050 the number of people living with Alzheimer’s could triple. 40% of patients living with Alzheimer\u27s disease are undiagnosed. Early detection promotes better dementia care, lowers costs of care, and increases quality of lifehttps://scholarworks.uvm.edu/fmclerk/1142/thumbnail.jp

Third Order Differential Subordination for Analytic Functions Involving Convolution Operator

في هذا البحث, من خلال استخدام المؤثر المعمم الجديد تم الحصول بعض نتائج التابعية التفاضلية من الدرجة الثالثة ونتائج التابعية التفاضلية العليا  للدوال التحليلية .كذلك تم تقديم بعض نظريات من نوع الساندوج .       In the present paper, by making use of the new generalized operator, some results of third order differential subordination and differential superordination consequence for analytic functions are obtained. Also, some sandwich-type theorems are presented

Multi-objective optimisation for minimum quantity lubrication assisted milling process based on hybrid response surface methodology and multi-objective genetic algorithm

© 2019 by SAGE Publications Ltd.Parametric modelling and optimisation play an important role in choosing the best or optimal cutting conditions and parameters during machining to achieve the desirable results. However, analysis of optimisation of minimum quantity lubrication–assisted milling process has not been addressed in detail. Minimum quantity lubrication method is very effective for cost reduction and promotes green machining. Hence, this article focuses on minimum quantity lubrication–assisted milling machining parameters on AISI 1045 material surface roughness and power consumption. A novel low-cost power measurement system is developed to measure the power consumption. A predictive mathematical model is developed for surface roughness and power consumption. The effects of minimum quantity lubrication and machining parameters are examined to determine the optimum conditions with minimum surface roughness and minimum power consumption. Empirical models are developed to predict surface roughness and power of machine tool effectively and accurately using response surface methodology and multi-objective optimisation genetic algorithm. Comparison of results obtained from response surface methodology and multi-objective optimisation genetic algorithm depict that both measured and predicted values have a close agreement. This model could be helpful to select the best combination of end-milling machining parameters to save power consumption and time, consequently, increasing both productivity and profitability.Peer reviewedFinal Published versio

Knowledge of hepatitis C screening and management by internal medicine residents: trends over 2 years

Over 2 million people in the United States are infected with hepatitis C, and there has been an explosion in knowledge regarding this disease in the last decade. Internal medicine residents must be able to identify patients at risk for hepatitis C and institute appropriate diagnostic testing and referral of these patients. Methods : A survey regarding hepatitis C risk factors and the management of hepatitis C patients was administered on three occasions over 15 months (time 0, 1 month, and 15 months) to members of a large university-based internal medicine residency. Results : During the study period 59 residents completed all three surveys. Less than half of the residents (39%) ask patients about hepatitis C risk factors. Only 58% reported that they would refer a hepatitis C antibody positive patient with elevated liver enzymes to a subspecialist on the initial survey. The residents who did not refer patients cited low response rates, high side-effect profiles, and the high cost of therapy as reasons for not referring the patient. There was significant improvement (58% vs 78%, p < 0.01 ) in the rate of patient referral during the 15-month study period but no substantial improvement in the other knowledge deficits. Conclusions : The knowledge base of the internal medicine residents about hepatitis C screening and management is suboptimal. New, more effective hepatitis C education programs for internal medicine residents should be initiated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75407/1/j.1572-0241.2002.05708.x.pd

Knowledge, attitude and practice of Tanta University medical students towards hepatitis B and C

Background: Egypt lies among the world’s highest prevalence rates of HCV and intermediate levels of HBV infection. The objectives of the study were detection of the knowledge, attitude and practice of Medical Students of Tanta University towards hepatitis B and C.Methods: This was a cross-sectional study, conducted in The Faculty of Medicine, Tanta University, Egypt; from 15th October 2013 to 15th of January 2014.Results: The study included 185 Students; their ages ranged between 17 to 28 years with a mean 20±1.731years. Sixty percent of students were males and 65% were urban residents. 50.8% of the participants were in the basic level of the academic study. More than half (57.85%) of the participants had sufficient knowledge, 77.3% of them had a positive attitude towards hepatitis C and B and more than two-thirds (68.1%) showed good practice. A significant association occurred between a positive attitude and good practice. Sufficient knowledge was significantly recorded among older students, females, urban residents and the clinical stage students. The most frequent sources of student information were family or friends, internet followed by TV or radio, healthcare workers, and newspapers.Conclusions: The students had reasonable knowledge, positive attitude and good practices towards B and C viral hepatitis. Areas of insufficient knowledge needed to be reinforced included some modes of transmission, complications, and treatment for B and C viral hepatitis

The Level of Psychological Anxiety of the Coronavirus Pandemic among Omani, Bahraini and Residents Families and their Relationship to some Demographic Variables

هدفت الدراسة الحالية إلى تحديد مستوى القلق النفسي تجاه فيروس كورونا (COVID-19) لدى الأسر العُمانية والأسر البحرينية والمقيمين، وتحديد فروق مستوى القلق تجاه فيروس كورونا تعزى للجنس والمؤهل العلمي والعمر وطبيعة العمل. وتكونت عينة الدراسة من 2107 مستجيبًا تم اختيارهم بالطريقة العشوائية. وتم استخدام استبانة للقلق من إعداد الباحثات. وقد أظهرت النتائج أن مستوى القلق جاء متوسطًا، كما أظهرت النتائج عدم وجود فروق في مستوى القلق بين الأسر العمانية والبحرينية، بينما كان مستوى القلق مرتفعًا لدى المقيمين مقارنة بالمواطنين في كلا الدولتين. وأظهرت النتائج أن الإناث هن الأكثر قلقًا من الذكور. وحسب العمر فقد كان الذين أعمارهم أكثر من 40 سنة أقل قلقًا من غيرهم. وقد اتضح أن أصحاب المؤهل العلمي المتدنِ (الثانوي وأقل) أكثر قلقًا من ذوي المؤهلات التعليمية العليا. وحسب طبيعة العمل فقد اتضح أن العاطلين عن العمل أكثر قلقًا من العاملين والمتقاعدين. وقدمت الدراسة مجموعة من التوصيات.This study aimed to identify the level of psychological anxiety about the Corona Virus (COVID-19) among Omani, Bahraini and Residents families, and to identify if there are differences in the level of anxiety due to gender, qualification, age, and job title. The study sample consisted of 2107 respondents, which were selected randomly. An anxiety questionnaire that was developed by the researchers was used as the main research tool. The results showed that the level of anxiety was moderate. The study also showed no differences in the level of anxiety between Omani and Bahraini families, while the level of anxiety was high among residents compared to citizens in both countries. The results indicated that females a have higher level of anxiety than males do. In addition, respondents who were above 40 years have lower anxiety than others. As for qualification, the study showed that respondents who have a secondary level qualification (or less) are feeling anxious more than those with higher qualifications. Finally, the unemployed respondents were found to be more anxious than those who have jobs and the retirees. This study suggested a number of recommendations

Comparative Analysis of Downlink Packet Scheduling Algorithms in 3GPP LTE Networks

Long Term Evolution (LTE) mobile network aims to support high speed network services even in highmobility scenarios. To achieve this goal, LTE adopts some advanced features in Radio Resource Management (RRM) procedures. Among them, LTE packet scheduling plays a fundamental role in maximising system performance. In this paper, a comparative analysis on the performances of Proportional Fair (PF), Exponential/Proportional Fair (EXP/PF), Exponential (EXP) Rule, MaximumLargest Weighted Delay First (M-LWDF), Logarithmic (LOG) Rule and Frame Level Scheduler (FLS) LTE downlink packet scheduling algorithms is reported. Performance is evaluated in single cell with interference environment while increasing user number and user speed. Results show that for multimedia flow, FLS scheme outperforms other five schemes in terms of packet delay, packet loss ratio, and average throughput, whereas for best-effort flow, EXP-PF scheme shows better average throughput performance on average as compared with other algorithms being considered herein

A Design and Implementation of an Ambulatory Electrocardiogram (ECG) Acquisition Circuit for Emergency Application

© 2018 IEEE. This paper presents the design and development of an ECG data acquisition circuit for emergency applications. The ECG signal extraction method and the design of the analogue front-end circuit are discussed. This design has been implemented in a printed circuit board (PCB), with comparable size to a 50 cent Australian coin. By applying the testing approach with this prototype, the output ECG trace quality is overall satisfactory with a clear display of QRS complex and certain robustness to motion artifacts