Iterative Approach on Redesigning and Construction of a Pipe Inspection Robot

A pipe inspection robot is a device that is inserted into pipes to check for obstructions or damage. These robots are traditionally manufactured offshore, are extremely expensive, and are often not adequately supported in the event of malfunction. This had resulted in Associated Environmental Services Limited, a New Zealand utiliser of this equipment, facing significant periods of down-time as they wait for their robots to be repaired. Recently, they were informed that several of their robots were no longer supported. At their instigation, this project was conceived to redesign the electronics and control system of one of these pipe inspection robots, utilising the existing mechanical platform. Requirements for the robot were that it must operate reliably in confined, dark and wet environments, and provide a human user with a digital video feed of the internal status of the pipes. This robot should, as much as possible, incorporate off-the-shelf components, facilitating cheap, and potentially on-site repair. This project details the redesign and construction of such a robot. It employs three electronic boards integrated with the mechanical components and provides video feedback via a custom graphical user interface. Although at the prototype stage, the electronic redesign has been successful, with a cost of less than a tenth of the original robot purchase price

Properties of latent interface-trap buildup in irradiated metal-oxide-semiconductor transistors determined by switched bias isothermal annealing experiments

Isothermal annealing experiments with switched gate bias have been performed to determine the properties of the latent interface-trap buildup during postirradiation annealing of metal-oxide-semiconductor transistors. It has been found that a bias-independent process occurs until the start of the latent interface-trap buildup. During the buildup itself, oxide-trap charge is not permanently neutralized, but is temporarily compensated. (C) 2000 American Institute of Physics. (DOI: 10.1063/1.1336159

Analysis of Industrial Companies Business Goals in Conditions of Uncertainty

189-192The appropriate groups are given in the paper of business goals in industrial companies in the conditions of uncertainty using BSC (Balanced Scorecard) and the FDM (Fuzzy Delphi Method) for each of the four independent perspectives: the perspective of learning and development, the internal processes perspective, the perspective of the user, and the financial perspective. The analysis resulted in determining the ranking of business goals by individual perspectives and defining the specific steps that need to be taken to advance in achieving the priority goals

A comparison of the hard-switching performance of 650V power transistors with calorimetric verification

We compare the switching losses of four equivalent silicon and wide-bandgap 650V power transistors operated in a hard-switched half-bridge configuration, switching 400V at 40A. Each transistor is mounted on an identical PCB and driven by a gate drive circuit matched to its requirements. Switching speed is maximised by a PCB design featuring very low parasitic inductance and the use of zero external gate resistance (where possible). Switching losses are measured electrically using a Double Pulse Test (DPT) method. However, high-bandwidth electrical measurements are prone to error and so we assess the gain accuracy, offset accuracy, and the bandwidth requirements of the DPT measurements, and then verify the DPT results by calorimetry. The electrical and calorimetric measurements are shown to agree to within 5%. Comprehensive plots of gate-source voltage, drain-source voltage, and source current are provided for all transistors over a junction temperature range of 50-150°C. The ratio of the total half-bridge switching losses is 1:3.2:14:31 for the GaN HEMT, SiC MOSFET, Si IGBT, and Si superjunction MOSFET, respectively

Case Report of Acute Vitamin D Intoxication in an Infant

© 2014, Serbia Medical Society. All rights reserved. Introduction Vitamin D intoxication represents a rare and potentially serious pathological condition caused by the excess of calcium and phosphorus. We are presenting an infant with vitamin D intoxication due to excessive daily administration, as well as therapeutic procedures that prevented its adverse effects. Case Outline A 1.5-month-old female infant, born at term, exclusively breastfed and without any complaints and abnormalities of physical findings, was observed due to the data that during the preceding month, by her mother's mistake, she had received about 200,000 IU of vitamin D3. Laboratory analyses showed a high serum level of 25(OH)D (>400 nmol/L) and calcium (2.72 mmol/L), lowered PTH (6.6 pg/ml) and high urinary calcium/creatinine ratio (1.6), while other findings, including urotract ultrasonography image, were within normal limits. Treatment based on the discontinuation of vitamin D administration, infant's forced water intake, as well as the application of 2-month prednisolone and 4-month pheno-barbitone and furosemide, resulted in complete normalization of the laboratory indicators of vitamin D overdose, as well as the prevention of its adverse effects.Conclusion By timely recognition and adequate treatment, including triple therapy with prednisolone, phenobarbitone and furosemide, adverse effects of acute vitamin D intoxication can be prevente

Fast switching of high current WBG power devices

Wide-band-gap power devices, such as Gallium Nitride High Electron Mobility Transistors and Silicon Carbide Field-effect Transistors, offer impressively fast switching performance compared to their traditional Silicon counterparts. However, Si designs have not stood still, and new generations of these devices offer good switching performance at competitive prices. This paper makes a comparative study between a representative selection of 650 V SiC MOSFET, GaN HEMT, and Si IGBT power switching devices. The devices are switched as fast as possible using a low inductance PCB design and no external gate resistors. A mathematical analysis of switching energy losses is presented, along with SPICE simulation and experimental test results for comparison

Analysis of Industrial Companies Business Goals in Conditions of Uncertainty

The appropriate groups are given in the paper of business goals in industrial companies in the conditions of uncertainty using BSC (Balanced Scorecard) and the FDM (Fuzzy Delphi Method) for each of the four independent perspectives: the perspective of learning and development, the internal processes perspective, the perspective of the user, and the financial perspective. The analysis resulted in determining the ranking of business goals by individual perspectives and defining the specific steps that need to be taken to advance in achieving the priority goals

Applying eXplainable AI Techniques to Interpret Machine Learning Predictive Models for the Analysis of Problematic Internet Use among Adolescents

This research focusses on the potential application of artificial intelligence (AI) techniques in the analysis of behavioural addictions, specifically addressing problematic Internet use among adolescents. Using tabular data from a representative sample from Serbian high schools, the authors investigated the feasibility of employing eXplainable AI (XAI) techniques, placing special emphasis on feature selection and feature importance methods. The results indicate a successful application to tabular data, with global interpretations that effectively describe predictive models. These findings align with previous research, which confirms both relevance and accuracy. Interpretations of individual predictions reveal the impact of features, especially in cases of misclassified instances, underscoring the significance of XAI techniques in error analysis and resolution. Although AI’s influence on the medical domain is substantial, the current state of XAI techniques, although useful, is not yet advanced enough for the reliable interpretation of predictions. Nevertheless, XAI techniques play a crucial role in problem identification and the validation of AI models

Relationship Between Regional Distributions of Cytochrome C Oxidase and Copper-Delivering Chaperones in Sclerotic Hippocampi of Epilepsy Patients

Aims: A drop in copper level and the loss of energy homeostasis are both portrayed in mesial temporal lobe epilepsy (mTLE) with hippocampal sclerosis (HS) patients. Cytochrome c oxidase (COX) represents a crossroad of energy and copper metabolism; it is a key component of mitochondrial machinery and contains two copper centers. Our aim here was to examine the link between COX activity and the copper transporting system in HS. COX activity and the levels of mRNA of selected chaperones - COX11, COX17, Sco1 and Sco2 were determined in 13 anatomically distinct hippocampal regions. Methods: Study was performed on seven hippocampal samples, four of which had been acquired during the course of amygdalohippocampectomy treatment of medically intractable epilepsy and three control postmortem samples. Adjacent slices were used for Nissl staining, COX activity assay and mRNA in situ hybridization with autoradiography. Densitometry was performed using ImageJ. Results: Overall COX activity was decreased in HS compared to controls (P = 0.0003). However, 5 regions showed significantly lower COX activity in HS and 8 did not. Subiculum showed slightly higher activity in HS. The levels of mRNA levels were lowered in HS in 6 regions for COX11, 10 regions for COX17, two regions for Sco1 and 11 regions for Sco2. Conclusions: Our findings suggest the loss of energy homeostasis in HS may be related to pathological changes in specific components of copper delivery to COX, and that the impact may vary between different hippocampal regions