Search results for "Function"

IMPROVING CNC MACHINE TOOLS ACCURACY USING MODELING AND COMPUTER SIMULATION TECHNIQUES

2007

Abstract The position was one of the first parameters that required the introduction of automatic control process. One of the most representative applications is represented by the feed drives of the computer numerically controlled (CNC) machine tools. Today, it is possible to use computer simulation techniques in analysing and synthesising position control systems. Thus, the behaviour of the CNC machine tools feed drives can be treated much more realistically. It is the purpose of this paper to show how simulation can be used to accurately represent, predict and improve the performance of a CNC machine tool feed servo drives.

Frequency Regulation of Hybrid Power System by Optimized Adaptive Fuzzy PID Controller

2020

In this study, an adaptive fuzzy PID (AFPID) regulator has been proposed for frequency control of hybrid power system. For controller parameter optimization, an upgraded Whale Optimization Algorithm (WOA) has been employed. In the proposed Upgraded WOA (UWOA) technique, a cosine function is incorporated in the original WOA for determining control parameter to manage the position of whales throughout optimization procedure. Furthermore, scaling factors are employed in original WOA to adjust the travel of whales in search procedure. Proposed UWOA technique is employed to design an AFPID controller for frequency regulation of a hybrid power system It is demonstrated that UWOA technique out per…

Progressive Web Apps for the Unified Development of Mobile Applications

2018

Progressive Web Apps (PWAs) allow for web applications to be developed in an offline-first approach. While Web apps traditionally did not properly function without an Internet connection, PWAs enable them to be downloaded, installed and used offline on various systems, including mobile devices and personal computers. We present an introduction to the state-of-art in research and practice. Based on this, we discuss various underlying concepts and technologies. Then, we scrutinize and compare PWAs against cross-platform app development approaches on both technical and overarching aspects. A list of suggestions for future research is also presented. We urge academia to keep up with the latest …

Motivation and Consequences of Internet and Mobile Phone Usage among the Urban Poor in Kampala, Uganda

2015

The Internet and mobile phones are rapidly diffusing throughout communities, and it is important to understand what people are actually doing with their access to these technologies. This study seeks to improve our understanding of the motivational factors and social and economic consequences of such use among the urban poor, which is examined through the Diffusion of Innovations Theory (DoI) and the Capability Approach (CA). The combined theoretical perspective was introduced to explore findings of an explorative case study conducted among the urban poor in Kampala, Uganda, where Internet access was found to be low due to high illiteracy and associated costs. On the other hand, mobile phon…

Economic Robustness Analysis of Adaptive Chart Schemes for Monitoring the Total Nonconformities Number in Inspection Units

2015

In recent years, a variety of enhanced schemes for the c chart have been developed aimed at the effectiveness improving of the related statistical process control (SPC) procedures. However, the performance of such chart schemes can be very sensitive to values assumed for some operating and cost parameters, in particular to the considered process shift magnitude arising from out-of-control conditions. In such a circumstance, the effectiveness of such chart schemes can be subjected to substantial reductions when they are implemented in operative contexts given that, in practice, such value is unknown and it can be very difficult to accurately estimate. For this reason, in the present paper i…

A Multi-Objective Design Approach for the c Chart Considering Taguchi Loss Function

2013

The present paper proposes a multi-objective design approach for the c chart, considering in the optimization process of the chart parameters both the statistical and the economic objectives. In particular, the minimization of the hourly total quality related costs is the considered objective to carry out the economic goal, whereas the statistical objective is reached by the minimization the out-of-control average run length of the chart. A mixed integer non-linear constrained mathematical model is formulated to solve the treated multi-objective optimization problem, whereas the Pareto optimal frontier is described by the e-constraint method. In order to show the employment of the proposed …

Estrogens and Stem Cells in Thyroid Cancer

2014

Recent discoveries highlight the emerging role of estrogens in the initiation and progression of different malignancies through their interaction with stem cell compartment. Estrogens play a relevant role especially for those tumors bearing a gender disparity in incidence and aggressiveness, as occurs for most thyroid diseases. Although several experimental lines suggest that estrogens promote thyroid cell proliferation and invasion, their precise contribution in stem cell compartment still remains unclear. This review underlines the interplay between hormones and thyroid function, which could help to complete the puzzle of gender discrepancy in thyroid malignancies. Defining the associatio…

IN-UTERO Δ9-TETRAHYDROCANNABINOL EXPOSURE IMPINGES ON BRAIN EXECUTIVE PROCESSES TOWARDS EMOTIONAL, COGNITIVE IMPAIRMENT, AND ALCOHOL VULNERABILITY IN…

2022

Prenatal exposure to cannabinoids evokes long-lasting functional alterations by targeting CB 1 receptors on developing cortical neurons

2015

The CB1 cannabinoid receptor, the main target of Δ(9)-tetrahydrocannabinol (THC), the most prominent psychoactive compound of marijuana, plays a crucial regulatory role in brain development as evidenced by the neurodevelopmental consequences of its manipulation in animal models. Likewise, recreational cannabis use during pregnancy affects brain structure and function of the progeny. However, the precise neurobiological substrates underlying the consequences of prenatal THC exposure remain unknown. As CB1 signaling is known to modulate long-range corticofugal connectivity, we analyzed the impact of THC exposure on cortical projection neuron development. THC administration to pregnant mice in…

Examining the association between exposome score for schizophrenia and functioning in schizophrenia, siblings, and healthy controls: results from the…

2021

European Community's Seventh Framework Program, European Commission [HEALTH-F2-2009-241909]; Scientific and Technological Research Council of Turkey, 2219 International Postdoctoral Research Fellowship Program; Spanish Ministry of Science and Innovation, Instituto de Salud Carlos III (SAM16PE07CP1, PI16/02012, and PI19/024)...