Design and validation of a fiber optic point probe instrument for therapy guidance and monitoring

Abstract in Undetermined ABSTRACT. Optical techniques for tissue diagnostics currently are experiencing tremendous growth in biomedical applications, mainly due to their noninvasive, inexpensive, and real-time functionality. Here, we demonstrate a hand-held fiber optic probe instrument based on fluorescence/reflectance spectroscopy for precise tumor delineation. It is mainly aimed for brain tumor resection guidance with clinical adaptation to minimize the disruption of the standard surgical workflow and is meant as a complement to the state-of-the-art fluorescence surgical microscopy technique. Multiple light sources with fast pulse modulation and detection enable precise quantification of protoporphyrin IX (PpIX), tissue optical properties, and ambient light suppression. Laboratory measurements show the system is insensitive to strong ambient light. Validation measurements of tissue phantoms using nonlinear least squares support vector machines (LS-SVM) regression analysis demonstrate an error of <5% for PpIX concentration ranging from 400 to 1000 nM, even in the presence of large variations in phantom optical properties. The mean error is 3% for reduced scattering coefficient and 5% for blood concentration. Diagnostic precision of 100% was obtained by LS-SVM classification for in vivo skin tumors with topically applied 5-aminolevulinic acid during photodynamic therapy. The probe could easily be generalized to other tissue types and fluorophores for therapy guidance and monitoring

Role of Artificial Intelligence (AI) art in care of ageing society: focus on dementia

open access articleBackground: Art enhances both physical and mental health wellbeing. The health benefits include reduction in blood pressure, heart rate, pain perception and briefer inpatient stays, as well as improvement of communication skills and self-esteem. In addition to these, people living with dementia benefit from reduction of their noncognitive, behavioural changes, enhancement of their cognitive capacities and being socially active. Methods: The current study represents a narrative general literature review on available studies and knowledge about contribution of Artificial Intelligence (AI) in creative arts. Results: We review AI visual arts technologies, and their potential for use among people with dementia and care, drawing on similar experiences to date from traditional art in dementia care. Conclusion: The virtual reality, installations and the psychedelic properties of the AI created art provide a new venue for more detailed research about its therapeutic use in dementia

Exergetic and Economic Evaluation of a Transcritical Heat-Driven Compression Refrigeration System with CO2 as the Working Fluid under Hot Climatic Conditions

The purpose of this research is to evaluate a transcritical heat-driven compression refrigeration machine with CO2 as the working fluid from thermodynamic and economic viewpoints. Particular attention was paid to air-conditioning applications under hot climatic conditions. The system was simulated by Aspen HYSYS® (AspenTech, Bedford, MA, USA) and optimized by automation based on a genetic algorithm for achieving the highest exergetic efficiency. In the case of producing only refrigeration, the scenario with the ambient temperature of 35 °C and the evaporation temperature of 5 °C showed the best performance with 4.7% exergetic efficiency, while the exergetic efficiency can be improved to 22% by operating the system at the ambient temperature of 45 °C and the evaporation temperature of 5 °C if the available heating capacity within the gas cooler is utilized (cogeneration operation conditions). Besides, an economic analysis based on the total revenue requirement method was given in detail

Evolution and Modern Approaches for Thermal Analysis of Electrical Machines

In this paper, the authors present an extended survey on the evolution and the modern approaches in the thermal analysis of electrical machines. The improvements and the new techniques proposed in the last decade are analyzed in depth and compared in order to highlight the qualities and defects of each. In particular, thermal analysis based on lumped-parameter thermal network, finite-element analysis, and computational fluid dynamics are considered in this paper. In addition, an overview of the problems linked to the thermal parameter determination and computation is proposed and discussed. Taking into account the aims of this paper, a detailed list of books and papers is reported in the references to help researchers interested in these topics

Outer raceway fault detection and localization for deep groove ball bearings by using thermal imaging

This paper discusses outer raceway fault detection and localization for rolling element bearings by means of thermal imaging. In particular, deep groove ball bearings have been monitored. Whereas bearings in industrial applications are usually fully covered, the used test setup allows to monitor the uncovered bearings to understand their heat increase and propagation. The main contribution of this paper is the methodology to process and analyse the thermal data of the bearings. The presented methodology is applied on both a healthy bearing and a bearing with outer raceway fault. By revealing significantly higher temperatures for the faulty bearing than for the healthy bearing, thermal imaging enables fault detection. Additionally, the stationary characteristic of the outer ring allows to locate the outer raceway fault by means of its thermal impact

Thermal analysis of induction and synchronous reluctance motors

In this paper, the thermal behavior of two induction motors (2.2 and 4 kW, four poles) and two synchronous reluctance motors [(SynRMs) transverse-laminated] are investigated and compared. Both motor types use the same stator but have different rotors. Using a lumped-parameter simulation program, a thermal analysis has been also carried out, and the obtained results have been compared with the experimental ones. A direct comparison of the thermal behavior of the two motor types has thus been made for constant load and constant average copper temperature conditions. Inasmuch as the SynRM has negligible rotor losses compared with the induction motor, it is capable of a larger rated torque, from 10% to more than 20%, depending on the relative size of end connections and motor lengt

Evaluation of Radiation Thermal Resistances in Industrial Motors

This paper deals with the role of the radiation thermal resistances in industrial motors and describes a test set useful for the resistance evaluation. The test set is based on a vacuum chamber and on a numerical acquisition system, and the resistances are obtained by monitoring motor temperatures during a heating test. An analytical model that describes how the radiation resistance depends on the motor temperature is also provided. Experimental results obtained on a totally enclosed fan-cooled 150-W induction motor are shown and discussed

Task‐specific measurement uncertainty budget of Curvic‐coupling using analytical methods

A number of Industrial reference components manufactured by grinding to achieve tight dimensional tolerances. In this paper, we present an uncertainty budget of a reference forty-tooth #Curvic measured using an accurate Coordinate Measuring Machine (CMM) in a temperature-controlled laboratory. A number of measurements conducted on Curvicto assess measurement repeatability and reproducibility. Expanded uncertainty budget evaluated from twenty-one Influencing factors, giving8.7 µm (7.1 µm from Type A) and 11 µm (9.6 µm from Type A), respectively, for repeatability and reproducibility test (k >2). Measurement uncertainty due to steady-state thermal effects is 2.2 µm. An adaptable model is presented to evaluate transient thermal effects, a factor often neglected in measurement uncertainty. Thermal time constant uncertainty associated with transient thermal effects is evaluated u(τ)= ±398 s, which corresponds to ±15 % of thermal time constant expanded uncertainty, u(τ)= ±2570 s. #Curvic® (Curvic is a trademark of The Gleason Works, 1000 University Avenue, Rochester, NY, 14603, USA