Mechanical properties of large-scale composite structures according to process conditions

The purpose of this study is to determine the correct estimation of the concept design and laminating pattern for composites. In this study, the effect of carbon tow prepreg on the composite structure has been investigated. Also, this work evaluated the structural safety according to the laminating pattern and process technique by computer simulation. The laminating pattern of three kinds was designed through the normal shape. Also, process technique of two kinds were carried out in dry and wet method to produce composites structure. The result of FEA showed that the structural safety of carbon tow prepreg is not significantly superior to that of the structure with wet method material. However, considering the benefits of working environment and the reduction of the number of process, the possibility of replacing materials and process technique will be sufficient for composite structure.

Floating Memristor and Inverse Memristor Emulators with Electronic Tuning

The work reports two different configurations to emulate the floating memristor and inverse memristor behavior. The presented circuits are based on a modified concept of active element VDTA (Voltage Differencing Transconductance Amplifier) termed as MVDTA. The reported floating memristor employs only a single MVDTA and single grounded capacitance. On the other end, the floating emulation circuit of inverse memristor emulator is based on two MVDTAs and single grounded capacitance. The behavior of the realized element for both the configurations can be tuned electronically through biasing voltage. Also, there is no employment of any commercial IC or external circuitry for multiplication of analogue voltages which is generally required to implement memristive elements. Along with the circuit implementations, mathematical properties of ideal memristor and inverse memristor considering both symmetric as well as nonsymmetric models are discussed. All the emulation circuits are verified by executing simulations using CMOS 0.18[Formula: see text]um process technique under PSPICE environment. The reported circuits are also realized using commercially available IC LM13700 and results are presented.

OPTIMIZING COVID-19 VACCINE USAGE

ABSTRACTAs the worldwide vaccination, it is imperative to minimize vaccine wastage by effectively using all doses available. Vaccine wastage can occur at multiple points during the vaccination process, but it is mainly because the device dead space and the filling process technique. However, there are no studies discussing the waste volume effect of COVID-19 vaccines in clinical practice. There is an increasing COVID-19 vaccine demand that we estimate up to several billion dual doses. The objective of this study was to assess the number of 0.3mL doses obtained from a multiple-dose vial using 1ml and 3ml syringes with different type of needles replicating the first COVID-19 vaccination protocol.Our results suggest that it is possible to obtain six or seven doses from each vial instead five. We provide evidence to optimize between 20% and 40% additional vaccine doses per vial if the current 5-dose vials are used, making scarce supplies go further.It is our duty, as researchers, to ensure the efficacy and efficiency of the worldwide COVID-19 vaccination process. However, if standard syringes-needles and technique are used, there may not be sufficient volume to draw extra doses from a single vial.

Analytic Hierarchy Process-Based Decision-Making Framework for Formwork System Selection by Contractors

This article presents a study of the contractors' preference for formwork system selection in Indonesian context. As decision makers, contractors are faced with challenges in choosing the formwork system for a particular project. While conventional timber formwork has been the most used formwork system in Indonesia, aluminium formwork is present although it has not been widely used. Thus, this research investigates the current practices of available formwork systems and its selection criteria in Indonesia. A decision-making framework (DMF) is developed by considering the appropriate assessment criteria for formwork system selection. This framework is then implemented through analytic hierarchy process technique. The result shows that contractors tend to choose aluminium formwork with a preference at 79% compared to conventional timber formwork with a preference at 21%. These findings can be used as considerations for contractors to start using aluminium formwork due to its excellence compared to conventional timber formwork. This study also proves that the proposed DMF can be applied and provides a sound decision related to formwork system selection.