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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.

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.

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.

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.

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.