305 research outputs found
The Influence of Commercial PC Switched Mode Power Supply Interference on the PRIME PLC Performance
No full textIn the last few decades, the use of power converters is essential in the smart grid environment. Consequently, this leads to the presence of a high-level of conducted electromagnetic interference between the smart grid elements. This paper study the effect of two power converter modulation techniques: Normal convention modulation and spread-spectrum modulation, on the performance of the Power Line Communication (PLC) signal. The paper presents a practical implementation of the system and discusses the results for different operating scenarios
Electromagnetic Interference of Spread-Spectrum Modulated Power Converters in G3-PLC Power Line Communication Systems
No full textThe impact of spread-spectrum techniques used to mitigate EMI from power converters on Power Line Communication (PLC) systems is studied in this paper. A buck converter, utilizing a Random Carrier Frequency Modulation with Fixed Duty cycle (RCFMFD) based control is considered as a source of conducted EMI and a narrowband G3-PLC as the victim. It is shown that, although considered to be an EMI mitigating technique, the spread spectrum technique has a detrimental effect on the communication channel, which can be explained in the framework of Shannon’s information theory. Conventional emission evaluation methods are therefore incompatible with modern day’s technology
Experiencing the armed struggle : the Soweto generation and after
No full textIncludes bibliographical references (p. 354-369).This study explores the experiences of the rank-and-file soldiers of Umkhonto we Sizwe and the Azanian People's Liberation Anny. Extensive interviews by the author and other researchers reveal the voices of the soldiers themselves. The African National Congress and Pan African Congress archives at the University of the Western Cape and the University of Fort Hare supplement and verify these oral testimonies, as do some published sources. Most previously published materials about the armed struggle against apartheid have already focused on diplomacy, strategy and tactics, operations, leadership, and human rights abuses to the neglect of the soldiers' actual experiences. This study complements these with significant new oral history materials from the Soweto generation of soldiers and their successors. When dealing with MK, many authors have documented issues of the camp structure in Angola, and operations inside South Africa, so much of this detail is only addressed briefly, leaving space to explore the soldiers' experiences. In the case of APLA, very little has been written on its history, and more detail is provided on these subjects. This study therefore deals with the soldiers' politicisation and motivation for joining the armed struggle, their experiences in leaving South Africa and training in exile, the crises in exile which limited their effectiveness for a time, their return to fight in South Africa, and their difficulties in the "new" South Africa. These materials reveal that vast problems remain facing these veterans of the struggle against apartheid, and that they have the potential, if properly supported and employed, to contribute substantially to the development of present day South Africa. Conversely, if their neglect continues, they also have the potential to bring vast harm to the country. Further use of the investigative tools of oral history, especially if extended to the former soldiers' vernacular languages, is necessary to augment the history of South Africa, and these soldiers' contributions
The Effect of EMI Generated from Spread-Spectrum-Modulated SiC-Based Buck Converter on the G3-PLC Channel
No full textPower line communication (PLC) is increasingly emerging as an important communication technology for the smart-grid environment. As PLC systems use the existing infrastructure, they are always exposed to conducted electromagnetic interference (EMI) from switching mode power converters, which need to be tightly controlled to meet EMC regulations and to ensure the proper operation of the PLC system. For this purpose, spread-spectrum modulation (SSM) techniques are widely adopted to decrease the amplitude of the generated EMI from the power converters so as to comply with EMC regulations. In this paper, the influence of a spread-spectrum-modulated SiC-based buck converter on the G3-PLC channel performance is described in terms of channel capacity reduction using the Shannon–Hartley equation. The experimental setup was implemented to emulate a specific coupling path between the power and communication circuits and the channel capacity reduction was evaluated by the Shannon–Hartley equation in several operating scenarios and compared with the measured frame error rate. Based on the obtained results, SSM provides the EMI spectral peak amplitude reduction required to pass the electromagnetic compatibility (EMC) tests, but results in increased EMI-induced channel capacity degradation and increased transmission error rate in PLC systems
Conservation in an Islamic context a case study of Makkah
No full textThe Holy Qu’ rān contains many injunctions for Muslims to respect and conserve the natural environment but few address the built environment. Habitat at the time of the Prophet (PBOH) was in the vernacular and relatively impermanent. The first habitat was the cave, the second the tent and then simple flat roofed buildings of post and lintel construction made of mud and rubble. Later buildings were not indigenous but reflected the architectural styles and techniques of Muslim pilgrims from beyond the Arabian Peninsula. Permanent exotic buildings were later erected as reminders of holy places and events. This work advances a case to restore and preserve historic and religious sites in Makkah, Saudi Arabia. Makkah is the destination for millions of Muslim pilgrims who annually pay homage to Allah during the occasions of Hajj, Ramadan and Umra. The tranquillity and peaceful ambience that one associates with the holiest of Islamic experiences have, over the years, given way to jostling crowds of people who must be expediently housed, fed, transported, and protected. Due to the lack of planning and the insensitive but profitable development of the city, Makkah is in grave danger of becoming a bustling metropolis instead of a sanctuary where pilgrims gather to perform their religious rites and reaffirm their dedication to Allah. The author calls for professional planning and international cooperation to guide future development for this expanding and sensitive area. The author's ideas are grounded in practical and aesthetic study, therefore, the political, environmental and economic issues are examined in relationship to religious, historic and artistic values. The author makes proposals for a future Makkah that would provide pilgrims with the physical comforts, security, and serene environment they deserve—without destroying the city they came to visit. The author discusses preservation and conservation in the western world and the need for their acceptance in Muslim countries, the former being an aesthetic and intellectual concept sustained by law and the latter being the prescribed free expression of the individual unhindered by material considerations. Both worlds are rapidly being overwhelmed by materialism, but body, mind and spirit combine in making us aware of our surroundings and the way in what we see around us has come into being
The Pherobase
No full textThe Pherobase was developed by Dr. Ashraf El-Sayed, a research scientist at HortResearch in New Zealand, with the primary objective of providing "coverage of the literature published on chemical communication in insects." The Pherobase is intended for use by both scientific and non-scientific communities and currently contains "over 10000 entries, around 3000 molecules, and over 32000 static html pages that make it the world's largest database of behavior modifying chemicals." The site contains multiple Insect indices for such categories as Order, Family A-Z, and Species; References indices such as Discovery by Author, Discovery by Year, and References A-Z; and indices for Compounds, Compounds by Family, and Compounds by Genus. The site also contains a Contribution Form, and number of online forums relating to The Pherobase
Influence of Random Modulated Power Converter on G3 Power Line Communication
No full textPower Line Communication (PLC) technologies are being used in many applications and offer the advantage of utilizing existing power cables for both power and data transmission, thus minimizing cost and complexity. Nevertheless, PLC technology requires further investigation to solve possible co-existence issues. Indeed, recent studies confirmed that alternative modulation schemes such as Random Pulse Width Modulation (RPWM), applied to switching-mode power converters to minimize conducted emissions, detrimentally interfere with the PLC system. This paper presents an experimental test campaign aimed at investigating the effects of RPWM on the G3-PLC system, with the final goal of understanding the conditions under which RPWM schemes can be considered as an effective alternative to conventional Pulse Width Modulation (PWM) in applications involving PLC systems. In details, the effects of different RPWM parameters such as switching frequency, modulation index, and Random Number Update Rate (RNUR) on the G3-PLC is investigated. In addition, different RPWM schemes such as Random Frequency Modulation (RFM) and Random Pulse Position Modulation (RPPM) are compared in terms of performance so as to highlight which RPWM is best suited to assure coexistence with PLC systems. The impact of RPWM on the communication channel is evaluated in terms of Frame Error Rate (FER), Channel Capacity, and Channel Capacity Loss metrics. Experimental results confirmed that randomly modulated converters with switching frequencies near the G3-PLC bandwidth cause more significant disturbance and possible coexistence issues than the switching frequencies out of this range. Results also show that the modulation index and the RNUR of RPWM have a direct effect on the communication channel. Moreover, a trade-off between Electromagnetic Interference (EMI) reduction and coexistence issues is observed: RFM, which is very effective for EMI reduction, is found to be very disruptive for G3-PLC, compared to alternative random modulation techniques such as RPPM
Effects of the Switching Frequency of Random Modulated Power Converter on the G3 Power Line Communication System
No full textPower Line Communication (PLC) technologies utilize existing power cables for both power and data transmission which minimizes cost and complexity. However, recent studies show that alternative modulation schemes such as Random Pulse Width Modulation (RPWM), applied to power converter to minimize conducted emissions, have possible side effects on the PLC system. In this work, the effects of the switching frequency of randomly modulated power converter on the G3-PLC system is investigated. To this end, a range of switching frequencies from 10 kHz-100 kHz is applied to a randomly modulated DC-DC converter and its potential effect on the G3-PLC is studied. Experimental results confirmed that switching frequencies near the bandwidth of the G3-PLC caused significant disturbance and possible coexistence issue compared to the frequencies out of this range. Moreover, there is a tradeoff between Electromagnetic Interference (EMI) reduction and coexistence issue that is Random Frequency Modulation, which is very effective for EMI reduction, is found to be very disruptive for G3-PLC, compared to alternative random modulation techniques like Random Pulse Position Modulation
Electromagnetic Interference of Power Converter with Random Modulation on the Power Line Communication System
No full textRandom Pulse Width Modulation (RPWM) allows controlling the switching signal of power converters in order to reduce the harmonic peaks by spreading the noise spectrum. Currently, many manufacturers of power converters are deploying this modulation scheme in order to comply with Electromagnetic Compatibility (EMC) test requirements. However, when the converters coexist with Power Line Communication (PLC) systems, such as in Smart Grid (SG) applications, resorting to RPWM needs further investigations since it potentially affects the communication channel by increasing the bit error rate. This possible detrimental effect is investigated in this work, by considering a PLC system for automatic meter reading (AMR) implemented in a SG application. To this end, the model of a complete PLC system is implemented in SIMULINK, and Quadrature Phase Shift Keying (QPSK) modulation is used to model the PLC modems in the communication channel. Results show that, even if the deployment of RPWM techniques may lead to an appreciable reduction/spreading of the peaks in the noise spectrum, it may also lead to an increase of the bit error rate on the PLC system
Relationship between Nursing Students' Motivation to Learn and Their Competency Self-Efficacy at Secondary Technical Schools of Nursing
No full textAbstract: Motivation to learn and competency self-efficacy(CSE) are two of the most influential factors that affect nursing students academic performance and clinical success. Aim: Investigate the relationship between nursing students' motivation to learn and their competency self-efficacy. Study design: A descriptive correlational research design was utilized to conduct this study. Setting: in 6 schools (3 female- 3male) out of 19 Secondary Nursing Technical Schools in Kafr El-Shikh governorate. Subjects: included Nursing Students in the previously selected settings (n=278) (134 female and 144 male). Tools: Two tools were used to conduct this study: Motivation to learn questionnaire and Nursing competency self-efficacy scale (NCSE). Results: The finding of this study revealed that the vast majority of the studied nursing students had high level of motivation to learn and nursing students had high level of competency self-efficacy. Conclusion: There was high levels of nursing students’ motivation to learn and high levels of competency self-efficacy (CSE). A statistically significant relationship was noticed between motivation to learn and competency self-efficacy. Recommendations: Develop strategies to motivate nursing students to learn and improve their competency self-efficacy.
Keywords: Motivation to learn, Nursing competency self-efficacy, Nursing students.
Title: Relationship between Nursing Students’ Motivation to Learn and Their Competency Self-Efficacy at Secondary Technical Schools of Nursing
Author: Asmaa Gomaa El-Gaafarey Mohamed, Neamat Mohamed El-sayed, Heba Mohamed Alanwar Ashour
Title: Relationship between Nursing Students’ Motivation to Learn and Their Competency Self-Efficacy at Secondary Technical Schools of Nursing
Author: Asmaa Gomaa El-Gaafarey Mohamed, Neamat Mohamed El-sayed, Heba Mohamed Alanwar Ashour
International Journal of Novel Research in Healthcare and Nursing
ISSN 2394-7330
Vol. 10, Issue 1, January 2023 - April 2023
Page No: 22-35
Novelty Journals
Website: www.noveltyjournals.com
Published Date: 12-January-2023
DOI: https://doi.org/10.5281/zenodo.7528763
Paper Download Link (Source)
https://www.noveltyjournals.com/upload/paper/Relationship%20between%20Nursing%20Students-12012023-1.pdfInternational Journal of Novel Research in Healthcare and Nursing, ISSN 2394-7330, Novelty Journals, Website: www.noveltyjournals.co
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