Calibration and Validation of a Cone Crusher Model with Industrial Data

This paper reports the calibration and validation of a cone crusher model using industrial data. Usually, there are three calibration parameters in the condensed breakage function; by contrast, in this work, every entry of the lower triangular breakage function matrix is considered a calibration parameter. The calibration problem is cast as an optimization problem based on the least squares method. The results show that the calibrated model is able to fit the validation datasets closely, as seen from the low values of the objective function. Another significant advantage of the proposed approach is that the model can be calibrated on data that are usually available from industrial operation; no additional laboratory tests are required. Calibration and validation tests on datasets collected from two different mines show that the calibrated model is a strong candidate for use in various dynamic simulation applications, such as control system design, equipment sizing, operator training, and optimization of crushing circuits.

Impacts of Air Conditioning Equipment Sizing on Energy Performance of US Office Buildings

The paper summarizes the results of a systematic and comprehensive analysis to investigate the impacts of inadequate sizing air conditioning (AC) systems on the overall energy consumption of medium and large office buildings located in representative US cities. The effects of proper sizing on the overall and disaggregated AC systems are evaluated in terms of energy consumption, peak demand, equipment run-time, and indoor thermal comfort. The presented analysis covers the performance a wide range of AC equipment components that serve US office buildings including packaged rooftop units as well as central cooling plants. The analysis results indicate that oversizing penalties can be significant on the annual energy consumption and electrical peak demand as well as capital costs for both medium and large office buildings. In particular, the reliance on simplified calculation methods and rules-of-thumb to determine equipment capacities can lead to significantly oversizing AC systems for office buildings in the vast majority of US climates and can result in increases of annual energy consumption and electrical peak demand of up to 29%. Moreover, oversizing increases capital costs required for air conditioning office buildings and extends cycling periods and associated structural stresses and failures of AC equipment.

Technical and Economic Analysis of Solar Photovoltaic Water Pumps against Conventional Systems in Common Crops in Ilocos Sur, Philippines

Irrigation is a well-established procedure on many farms and is practiced around the world. However, typical irrigation systems consume a great amount of conventional energy using electric motors and generators powered by fuel. The cost of solar panels has been continually decreasing, which encourages its usage in various sectors, including agriculture, where irrigation is a crucial economic driver. The study analyzed and compared PV technology against conventional irrigation technology in common crops in Ilocos Sur. Equipment sizes were optimally determined using available irrigation requirements, rainfall data, farm area, and available equipment sizes in Ilocos Sur. Equipment sizing and economic analysis were based on one hectare of land. The cash flow analysis was conducted over an assumed equipment life of 20 years to be able to come up with levelized water pumping costs. Results showed that with typical farmland in Ilocos Sur, the farmland must be alternately planted with rice and corn to be able to be fully utilized all year round. The study showed that the solar pump installation has a heavy upfront investment cost compared to the conventional system. Due to no fuel and little to no maintenance needed, the solar pump turned out to be more economically feasible in the long run. In the 20-year life of both equipment, pumping one cubic meter of water using a solar pump is only PHP 1.35 while for gasoline, it is PHP 5.44 or around four times more expensive based on the prevailing cost at the time of the study.

Sizing of natural crack using multi-output support vector regression method from multi-frequency eddy current testing signals

In the nondestructive evaluation for components of key equipment, sizing of natural crack is important in order to guarantee both the safety and efficient operation for large mechanical systems. Natural cracks have complex boundary and there may be electric current flowing through crack faces. If a simple model of artificial notch is used to simulate it, errors often occur in crack depth reconstruction from eddy current testing (ECT) signals. However, if a complex crack conductivity model is used, quantitative evaluation of natural crack will be transformed into a multivariable nonlinear optimization problem and the solution is difficult. In this paper, based on the relationship between crack parameters and features of multi-frequency ECT signals, a multi-output support vector regression algorithm using domain decomposition for parameters was proposed. The algorithm realized the quantitative evaluation of multiple parameters of crack in turn. Numerical examples with simulated and measured ECT signals were presented to verify the efficiency of the proposed strategy.

Pediatric Resuscitation

Respiratory failure is the most common cause of cardiopulmonary arrest in children. Early recognition of the critically ill child and aggressive management of respiratory failure and shock are crucial to preventing cardiopulmonary arrest. Although caring for a sick child can be highly stressful for emergency physicians, pediatric resuscitation largely mirrors that of adults, with special consideration of a few key anatomic and physiologic differences. It is important to have a systematic approach to patient assessment, medication dosing, and equipment sizing in order to cognitively offload the emergency provider. The following will help maximize performance in these high-stakes situations: the Pediatric Assessment Triangle combined with the familiar airway, breathing, circulation, disability, exposure approach; an age-, weight-, or length-based medication/equipment system; and routine application of Pediatric Advanced Life Support algorithms.

Pediatric Procedures

Many procedures in children occur less commonly than in adults, but there are a few unique features of performing interventions in children. Indications for these procedures are similar but equipment sizing, landmarks, and method techniques vary compared to those of adults. Bedside thoracostomy procedures including needle, catheter, and tube thoracostomy are critical in the emergency care of children, particularly for those with traumatic injuries. Needle cricothyrotomy is a last-ditch rescue airway for pediatric patients with an obstruction above the cricothyroid membrane that is unable to be ventilated or oxygenated with traditional airway techniques. Lumbar punctures are routinely performed in emergency medicine. Lumbar puncture is typically performed due to concern for meningitis. This chapter reviews both indications and techniques of tube and needle thoracostomy, lumbar puncture, and needle cricothyrotomy in children.