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Piezoelectric materials are widely used as an input transducer to harvest electrical energy. In this research, an optimized piezoelectric transducer (PZT-5H) has been designed for maximum efficiency. The transition system consists of an ideal mass, spring and damper. It has been modeled using MATLAB Simscape Toolbox™. Routh–Hurwitz criterion is applied to assess the stability of the transition system. The root-locus and step-response plots are generated for the stability analysis. Effects of varying stiffness, damping coefficient and thickness have been studied in designing of stack PZT-5H. The statistical analysis based on a Taguchi design of experiment and analysis of variance approaches is implemented to obtain the optimum output response from the energy harvester. Consequently, interval plots and a regression model are designed to establish an adequate relationship between the controllable factors and optimum output response of the energy harvester. The results are compared with the literature and they correlate well with each other.

In the 21st century, researchers have been showing keen interest in the areas of wireless networking and internet of things (IoT) devices. Conventionally, batteries have been used to power these networks, however, due to the limited lifespan of batteries and with the recent advancements in piezoelectric technology, there is a dramatic increase in renewable energy harvesting devices. In this research, an eco-friendly wind energy harvesting device based on the piezoelectric technique is analytically modeled, numerically simulated, and statistically optimized for low power applications. MATLAB toolbox SIMSCAPE is utilized to simulate the proposed wind energy harvester in which a windmill is used to produce rotational motion due to the kinetic energy of wind. The windmill’s rotational shaft is further connected to the rotary to linear converter (RLC) and vibration enhancement mechanism (VEM) for the generation of translational mechanical vibration. Consequently, due to these alternative linear vibrations, the piezoelectric stack produces sufficient electrical output. The output response of the energy harvester is analyzed for the various conditions of piezoelectric thickness, wind speed, rotor angular velocity, and VEM stiffness. It is observed that the electrical power of the proposed harvester is proportional to the cube of wind speed and is inversely proportional to the number of rotor blades. Furthermore, an optimization strategy based on the full factorial design of the experiment is developed and implemented on MINITAB 18.0 for evaluating the statistical performance of the proposed harvester. It is noticed that a design with 3 rotor-blades, having 3 mm piezoelectric thickness, and 40 Nm−1 stiffness generates the optimum electrical response of the harvester.

Stainless steel (SS) grade 316L is used for orthopedic implants due to its biocompatibility; yet the effort should be done to minimize the carcinogenic and inflammatory effects related to SS 316L implants. In this research, aluminide coating of Al–Si alloy on SS 316L is characterized by using optical microscopy, energy dispersive spectroscopy (EDS), nano-indentation and corrosion testing technique. Hot dip aluminizing process is used to coat the SS 316L specimens at 765 °C for 2 min immersion time. Half of the specimens are also diffusion treated in a Muffle furnace at 550 °C for 4 h to produce diffused specimens of SS 316L. Microstructural examination shows the formation of flat coating/substrate interface due to Si addition. EDS analysis confirms the formation of complex intermetallic at the coating/substrate interface which finally results in increasing the hardness and corrosion resistance properties of coating.

Metals especially gold, silver, platinum and copper are getting more attention for application in electronics field due to their versatile properties. In this paper, we selected the materials after comparison on the basis of their significant properties. Those properties are conductivity, physical properties, reactivity, cost and demand and supply. We investigate the conductivity of metals at various temperature values, their historically monthly prices along with their worldwide demand and supply. First, we compare their conductivity and resistivity for various values of temperature as well as by adding impurity into them. Secondly, we examined their responses when they are in contact with the atmosphere, their historically monthly prices, availability in the earth crust, and a brief discussion on the structure of these metals. These metals are widely used in electronics and jewelry because of their good conductivity, chemical stability and long lasting. We implemented the analytical hierarchy process for the parametric investigation of these metals which is a general theory of measurement. It has been used to derive ratio scales from both continuous and discrete paired comparison. This comparison is taken from actual measurement which reflects the relative strength of preferences. The metals are also useful to design electrical stimulator with low-frequency current to regulate the blood of the human body. By using the stimulator at acupuncture points to pass through small electrical signal is useful to control blood flow in the human body as well as provides relief in pain.

Piezoelectric materials have wide applications in the field of mechanical, aerospace and civil engineering because of its voltage dependent actuation. Piezoelectric material goes through voltage generation whenever deflection is induced in it and vice versa. Piezoelectric bimorph beam has been widely used for sensing and actuating. In the actuation mode, an electric field is applied across the beam thickness, one layer contracts while the other expands. This results in the bending of the entire structure and tip deflection. In the sensing mode, the bimorph is used to measure an external load by monitoring the piezoelectric induced electrode voltages. In this research work, a 2D bimorph piezoelectric actuator model having two layers made of polyvinylidene fluoride (PVDF) material was developed to examine the inverse piezoelectric effect. Finite element analysis (FEA) was carried out on specially designed actuator model by using MATLAB Partial Differential Equation (PDE) Toolbox™. Theoretical analysis has been carried out to measure the tip deflection under applied electric field. The laboratory test was performed to investigate the deformation behavior of piezoelectric actuator. It is observed that, more the electric field applied, more the material would be deformed in a particular direction. The experimental results are in good agreement with numerical results.

This research focuses on design and calculations for the horizontal axis wind turbine to fulfill energy demands at small scales in Pakistan. This is the design to produce about 5 kilowatts of electricity to share the load of average home appliances. Area chosen for this research is Pasni, Balochistan in Pakistan to build the wind turbine for electricity. Design values are approximated by appropriate formulas of wind energy design. In current research, turbine blade profile is designed by blade element momentum (BEM) theory. Warlock wind turbine calculator is used to verify the design parameters like wind speed, tip speed ratio (TSR) and efficiency factor. Effects of wind speed, wind power, TSR, pitch angle, blade tip angle, number of blades, blade design and tower height on power coefficient are analyzed in this research. Maximum power coefficient is achieved at a designed velocity of 6m/s. Design analysis is also performed on simulation software ANSYS Fluent. It is observed that designed velocity parameter of this research is very suitable for the turbine blade, so blade designing is perfect according to wind speed range.

Piezoelectric materials are widely used as smart structures in cubic reconnaissance satellites because of their sensing, actuating, and energy-harvesting abilities. In this study, an analytical model is developed in specific mechanical thermal shocking conditions. A special circuit and apparatus is designed for experimentation on the basis of the inverse piezoelectric effect. An equivalent circuit method is used to establish the relationship between the resistance and peak-to-peak voltage of lead zirconate titanate used as smart materials for cubic reconnaissance satellites. Various frequencies and resistance were applied in different mechanical thermal shocking conditions. Moreover, numerical simulations are conducted in various mechanical loading conditions to determine the accumulative effect. The model provides a novel mechanism to characterize the smart structures in cubic reconnaissance satellites. A rise in temperature increases peak-to-peak voltage; a rise in frequency decreases peak-to-peak voltage; and intensified resistance decreases peak-to-peak voltage. Based on experimentation and simulation, the optimum resistance is predicted for the various frequencies and temperatures. The various conditions may correspond to the different applications of smart structures for cubic reconnaissance satellites. The analytical calculations are in good agreement with experimental and numerical calculations.

Thermal energy produced by discrete and random electric sparks in electric discharge machining (EDM) melts surface material. A portion of this molten material is removed and the remaining material resolidified by rapid cooling in a hydrocarbon oil. The effect of repeated heating and cooling of the surface and sub surface material with complex temperature gradient results residual stresses in machined part. The aim of this investigation is to determine the distribution of residual stresses in the depth of machined material with respect to discharge current, most important electric parameter during EDM. It is well known that surface finish is dependent on discharge current. Therefore, investigations were carried out for smaller discharge current levels i.e. 3, 6, 9, 12 ampere. Hole-drill strain gauge method is used for the determination of residual stresses in the depth of material. For comparison purpose, residual stresses are also determined for conventionally turned specimens. This study provided quantitative analysis of the residual stresses for various discharge current in EDM which is a key parameter in deciding the service life of material.

Objective: To investigate the effect of simvastatin treatment on insulin sensitivity in type 2 diabetes mellitus patients. Study Design: A randomized case control study. Place and duration: In the Medicine Unit II of Holy Family Hospital Rawalpindi for one year duration from January 2018 to January 2019. Methods: The study was performed on 100 subjects with type 2 diabetes in both genders. Into two groups, patients were randomized. 50 subjects received Simvastatin 40 mg / day for 3 months and 50 volunteers were taken as controls. Both groups had same anthropometric properties (duration of diabetes, age, blood pressure and BMI) and biochemical (fasting plasma glucose, serum creatinine, lipid profile and fasting insulin level). Simvastatin (40 mg / day) was evaluated by insulin resistance (HOMA-IR) for the evaluation of homeostasis model for resistance of insulin after and before 3 months of management. Results: Simvastatin (40 mg / day) significantly reduced triglyceride, cholesterol and LDL levels but did not affect significantly sensitivity of insulin as determined by HOMA-IR. However, sensitivity of insulin was increased in people with resistance to insulin (P = 0.001 reduction, HOMA IR 1.92). Conclusion: Although short-term treatment with simvastatin (3 months) had no effect on sensitivity of insulin, lipid depletion had strong effect on all cases. Key words: Insulin sensitivity, Diabetes, Simvastatin, lipid profile.

Objective: To investigate an effective way to separate the abdominal wound dehiscence following emergency and elective laparotomies. Study Design: A comparative cross-sectional study. Place and Duration: In the Surgical Unit II of Holy Family Hospital, Rawalpindi for one year duration from July 2017 to July 2018. Materials and Methods: In the emergency or elective surgeries, 100 consecutive patients undergoing midline incision and laparotomy were included in the study. In order to see normal recovery, a wound examination was performed from the second postoperative day and the findings were recorded. Group A wound injuries were managed with full abdominal lavage and deep tension sutures and B group applied with Bogota bag application and abdominal wash. Results: Fifteen (11.5%) of the 130 patients developed full wound dehiscence (trapped abdomen). The incidence of abdominal rupture was significantly higher after emergency laparotomies (14/94, 14.89%), whereas one patient underwent elective laparotomy (1/36, 2.7%). Group A (n = 8) was managed with deep tension sutures and group B (n = 7) was treated with Bogota Bag. The results of deep tension sutures were associated with less morbidity, less surgery and lower mortality. Conclusion: Complete abdominal lavage with normal saline and closure with deep tension sutures is still an effective treatment in patients with complete wound dehiscence. Cases of abdominal closure due to a generalized intestinal edema or the need for further reoperation. Key words: Midline laparotomy, Abdominal wound dehiscence, Bogota bag, deep tension suture, burst abdomen.

In this paper, the functioning of dew-point cooler is improved in terms of its thermal effectiveness. For this reason, a heat and mass exchanger has been designed by using a counter-flow pattern incorporating Maisotsenko cycle (M-cycle) having effective absorbing material called Kraft paper on wet channel side and improved width to height ratio. Experimentation has been performed under various inlet air working parameters such as humidity, velocity and temperature in addition with changing feed water temperature. The results from the experiments specify that the dew-point and the wet-bulb effectiveness is achieved between 67–87 % and 104–120 % respectively. Analysis is performed with temperature variation between 25 and 45 °C at different absolute humidity levels ranging from 14.4 to 18 g/kg, while the inlet air velocity is varied between 0.88 and 1.50 m/s. Thus, the working ability of the improved design has been found 5 % more effective in terms of wet bulb effectiveness as compared to previous counter-flow designs.

In the present era, the renewable sources of energy are very much in demand i.e., piezoelectric materials, they play a vital role in the field of micro-electromechanical systems i.e., sensors and actuators. Cantilever based piezoelectric energy harvesters are very popular because of their high performance and utilization. In this research-work, energy harvester model based on a cantilever beam with bimorph PZT-5A having substrate layer of structural steel has been presented. The proposed energy scavenging system is designed in COMSOL Multiphysics to analyze the electrical output as a function of excitation frequencies, load resistances and accelerations. Analytical modeling is employed to measure the output voltage and power under pre-defined conditions of acceleration and load resistance. Experimentation is also performed to contemplate the relationship between independent and output parameters. Energy harvester is capable to produce maximum power of 1.16mW at a resonant frequency of 71 Hz under 1g acceleration having load resistance of 12kΩ.Its observed that acceleration and output power are directly proportional to each other. Moreover, the investigation conveys that experimental results are in good agreement with the numerical results. The maximum error obtained between the experimental and numerical investigation is found to be 4.3%.

Many countries of the world fulfill their power requirements through non-renewable energy resources which include fossil fuels, earth minerals and nuclear fuels. The massive use of these non-renewable energy resources has created an alarming situation resulting in harmful climatic variation throughout the world. So, the need of hour is to focus on sustainable and clean renewable energy resources to fulfill energy demands. In this regard, the ocean waves are considered significant renewable energy resource to extract the energy from sea waves. This research paper represents the parametric investigation of wave energy model based on oscillating water column technique. Self-rectifying impulse turbine of specific design parameters is used in this research work to convert maximum wave energy into mechanical energy. Designing of turbine blade, guide wave geometry and oscillating water column is performed on CREO and Pro-Engineer. While FEM software "Gambit and Fluent" are used to achieve fine meshing and profiles of tangential and radial velocity. Maximum efficiency attained from this designed wave energy model is 35%, while rpms of shaft are calculated 200. This paper realizes the fact that wave energy has a lot of potential for research.

Background and Objectives The optimal transfusion strategy in hip arthroplasty remains controversial despite existing guidelines. The aim of this study was to evaluate the transfusion practice in patients undergoing primary total hip arthroplasty (THA) or revision total hip arthroplasty (RTHA) in Denmark. Materials and Methods We performed a retrospective cohort study of all patients undergoing THA or RTHA in Denmark in 2008. Primary outcomes were intercentre variation in red blood cell (RBC) transfusion rates and the timing of transfusion related to surgery. Results Six thousand nine hundred thirty-two THA patients and 1132 RTHA patients were included for analysis of which 1674 (24%) THA and 689 (61%) RTHA patients received RBC transfusion. Of these, 47% of THA and 73% of RTHA patients received transfusion on the day of surgery. Transfusion rates between centres varied from 7 to 71% and between 26 and 85% in THA and RTHA patients, respectively. Patients receiving RBC transfusion had longer length of stay and for THA patients an increased odds-ratio (5·5) of death within 90 days. Conclusion Despite established guidelines, RBC transfusion practice in hip arthroplasty remains highly variable between Danish hospitals. The effect of RBC transfusion on outcome after hip arthroplasty should be established in prospective randomized controlled trials.

Energy harvesting is the process of attaining energy from the external sources and transforming it into usable electrical energy. An analytical model of piezoelectric energy harvester has been developed to determine the output voltage across an electrical circuit when it is forced to undergo a base excitation. This model gives an easy approach to design and investigate the behavior of piezoelectric material. Numerical simulations have been carried out to determine the effect of frequency and loading on a Lead zirconate titanate (PZT-5A) piezoelectric material. It has been observed that the output voltage from the harvester increases when loading increases whereas its resonance frequency decreases. The analytical results were found to be in good agreement with the experimental and numerical simulation results.

Fossil Fuels are considered the major sources to fulfill the world energy demand but their harmful effect on our environment are the main source of concern. So it is the need of time to utilize the such energy resources which are sustainable and environment friendly. As we know that more than seventy percent portion of earth is covered by the ocean. This source of energy is present in the form of ocean's water, the air above the ocean and the land beneath them. This paper presents a technique to extract the energy from ocean waves using oscillating water column chamber and self-rectifying impulse turbine. It also gives the brief introduction of oscillating water column used in the extraction of wave energy. Designing of oscillating water column is accomplished using Pro Engineer and CREO soft wares. The efficiency of this fabricated wave power plant is 35% and the rpms of shaft are 200. The research in this area will provide decentralized, sustainable and chemical emission free energy.

1. Sources of Islamic ethical and legal opinion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 2. Sanctity of life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 3. Sickness, ill health and death . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 4. Is medical treatment mandatory? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 5. Withdrawal of life sustaining treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Energy harvesting is the process of acquiring energy from the external sources and then further used to drive any system. Piezoelectric material was operated at various temperature but the characterization of the material mostly performed at room temperature. The depolarization in piezoelectric material occurs when the material is heated to its curie temperature and when mechanical stresses are high to disturb the properties of the material. The aim of this paper is to study the performance of lead zirconate titanate (PZT-5A) piezoelectric material under various temperatures and loading conditions. The output voltage of piezoelectric material decreases with increase of temperature. It was found that output voltage from the harvester increases when loading increases while its temperature decreases.

In 2007 and 2008 Danish Cancer Patient Pathways for 32 cancer types were developed and afterwards implemented on a national scale. Often bureaucrats, health professionals and politicians look upon the health sector in different ways and work independent of each other. In Denmark, as indeed internationally, patient pathways are frequently developed solely by health professionals and the consequence may be major difficulties in implementing the pathways on a national scale. In this article we describe how national Danish Cancer Patient Pathways were developed with a consensus seeking model and the impact it has had on the health system. The model used in Denmark ensured involvement and cooperation between bureaucrats, health professionals and politicians and afterwards a successful national implementation. The Cancer Patient Pathways has significantly reduced waiting times which is thought to increase survival. This experience gives important input to the continuous challenges on how to implement evidence based medicine on a national scale and stipulates a model for this process.