Acoustic methods in real-time welding process monitoring: Application and future potential advancement

The rapid advancement of the welding technology has simultaneously increased the demand for the online monitoring system in order to control the process. Among the methods that could be possibly used to assess the weld condition, an air-borne acoustic method grasps the attention from scholars due to its ability to provide a simple, non-contact, and low-cost measurement system. However, it is still lack of resources involving this subject in an attempt to deeply understand the emitted sound behaviour during welding especially when dealing with a complete deviation of a process parameter, welding types, workpiece material as well as the noise from the surrounding. This paper reviews the application of the acoustic method in monitoring the welding process. Specifically, this review emphasized the source of both structure-borne and air-borne acoustic during the welding process and the significance of applying the acoustic method in more detail. By focusing on the liquid state welding process, the scope of discussion converged on the arc and laser welding process. In the last part of this review, the potential future advancement of this method is pointed out before the overall conclusion is made.

Characteristics of six layered Al/Si3N4 functionally graded materials prepared through two-step pressureless sintering process

The rapid advancement of the welding technology has simultaneously increased the demand for the online monitoring system in order to control the process. Among the methods that could be possibly used to assess the weld condition, an air-borne acoustic method grasps the attention from scholars due to its ability to provide a simple, non-contact, and low-cost measurement system. However, it is still lack of resources involving this subject in an attempt to deeply understand the emitted sound behaviour during welding especially when dealing with a complete deviation of a process parameter, welding types, workpiece material as well as the noise from the surrounding. This paper reviews the application of the acoustic method in monitoring the welding process. Specifically, this review emphasized the source of both structure-borne and air-borne acoustic during the welding process and the significance of applying the acoustic method in more detail. By focusing on the liquid state welding process, the scope of discussion converged on the arc and laser welding process. In the last part of this review, the potential future advancement of this method is pointed out before the overall conclusion is made.

Economic appraisal in public healthcare: assessing efficiency and equity

This chapter is an introduction to economic appraisal. It explains underlying concepts, describes methods used, and discusses the application to public health. Economic appraisal comprises techniques that weigh up the costs of an action, such as providing a public health intervention to an at-risk population group, against the benefits that it provides. Important underlying principles are opportunity cost, social versus private costs and benefits, marginal costs and benefits, efficiency, and equity. There are different types of economic appraisal, each of which measures the costs and benefits of options being compared. Measuring costs involves identifying and describing resource use changes, quantifying them in physical units and valuing them. Issues in cost measurement include use of macro or micro-costing and dealing with inflation and time preference. There are several approaches that can be used to measure benefits depending on the type of economic appraisal being used; a measure of special interest is quality-adjusted life years (QALYs). Modelling is often used in economic appraisal to combine data on the costs and benefits of an intervention. Given the inherent uncertainties involved in economic appraisal it is good practice to undertake sensitivity analyses that investigate the impact of uncertainty. Methodological challenges in undertaking economic appraisals of public health interventions include the importance of equity and inequality considerations, establishing robust evidence of the effect of public health programmes, the relevance of QALYs, and accounting for multisectoral costs and benefits.

Development and initial tests of an urban comfort monitoring system

The paper presents a newly developed low-cost measurement system for outdoor comfort monitoring. The solution is based on IoT (Internet of Things) technologies and is cloud-connected. The system is able to collect physical environment data, and includes a movable GPS monitoring station as well as the subjective thermal sensation of pedestrians via a devoted app. The cloud interface promptly elaborates the received data to calculate outdoor thermal comfort indices such as UTCI (Universal Thermal Climate Index), MRT (mean radiant temperature), and ET (effective temperature). The system is conceived for supporting both fixed and traveling measurements, and to support correlation studies between monitored environmental variables and personal comfort sensations to promote the local adaptation of comfort indices. Results from early testing are also reported.

An Open-Source, Low-Cost Measurement System for Collecting Hydrometeorological Data in the Open Field

To realize precision agriculture at multiple locations in the field, a low-cost measurement system should be developed for easy collection of hydrometeorological data, such as temperature, moisture, and light. In this study, a compact and low-cost hydrometeorological measurement system with a simplified wire code, which is customizable according to the purpose of observation, was built using a circuit board that connects Arduino to the sensors, which was then implemented and analyzed. The developed system measures air and soil temperatures, soil water content, and photosynthetic photon flux density using a sensor connected to Arduino Uno and saves the continuous, high-temporal-resolution output to an SD card. The results obtained from continuous measurement showed that the data collected using this system was significantly better than those collected using commercially available equipment. Anyone can easily measure the weather environments by using this fully open, highly versatile, portable, and user-friendly system. This system can contribute to the growth and expansion of precision agriculture, field management, development of crop models, and laborsaving. It can also provide a global solution to ongoing agricultural issues and improve the efficiency of farming operations, particularly in developing and low-income countries.

First bioimpedance assessment for detecting effects caused by environmental stimuli on Grapevine ( Vitis vinifera L.): preliminary results

Plants comprise biological tissues where bioimpedance could be measured. Changes in values of these impedance parameters within tissues are the result of changes in the chemical composition of the sap, cellular depolarization, and ion transport in response to external stimuli such as water availability, diseases, and photosynthesis activity, among others. Therefore, the environmental effects on the plant change its morphology and physiology would be related to bioimpedance. In this way, bioimpedance could become a novel and powerful technique used to analyze, in-situ and in real-time, the physiologic activity and status. In this study, we assess the Evaluation Board AD5933EBZ as a bioimpedance low-cost measurement device to perform observations of module and phase of the bioimpedance, aimed to correlate them with the effects of environmental stimuli such as irrigation, CO2 concentration, sun exposure and temperature level in the grapevine.

The role of quality cost measurement in improving product quality

The research aims to demonstrate the knowledge pillars of quality costs and the role of measuring the elements of quality costs. This is excluding the elements of failure costs and identifying and improving the level of product quality. Any economic unit seeking to compete in the local and global markets must achieve better product specifications, i.e. higher quality. This cannot be done, but through the use of many techniques, methods and special skills. Quality costs act as a measure or indicator of the performance of the economic unit and the extent of improvement in it. This also contributes to the process of evaluating its strategic performance, for example, to what extent does the increase in spending on research and development costs contribute to reducing other costs? Thus, the economic unit should direct its attention towards the costs of preventing the activities that host value in a way that helps reduce the costs of evaluation and failure of both types (non-value-adding activities). Therefore, if the economic unit is able to produce high-quality products, this enables it to adopt a price policy in the markets and to enable it to achieve a competitive advantage , The most prominent results of the research are that the classification of quality costs is one of the main tasks for determining, calculating and analyzing quality costs. The economic unit that has decided to manage quality costs should select the appropriate quality cost model that includes the categories and elements of quality costs. The most important recommendations are to increase spending on activities, prevention (value-adding activities) in order to reduce evaluation costs and failure in quality and focus on the reduction in evaluation costs and failure of both types should be greater than the increase in the costs of the assessment.