146 research outputs found
55 dB High Gain L-Band EDFA Utilizing Single Pump Source
In this paper, we experimentally investigate the performance of an efficient high gain triple-pass L-band Erbium-Doped Fiber (EDF) amplifier structure with a single pump source. The amplifier gain and noise figure variation with EDF pump power, input signal power and wavelengths have been investigated. The generated backward Amplified Spontaneous Emission (ASE) noise of the first amplifier stage is suppressed by using a tunable band-pass filter. The amplifier achieves a signal gain of 55 dB with low noise figure of 3.8 dB at -50 dBm input signal power. The amplifier gain shows significant improvement of 12.8 dB compared to amplifier structure without ASE suppression
55 dB High Gain L-Band EDFA Utilizing Single Pump Source
In this paper, we experimentally investigate the performance of an efficient high gain triple-pass L-band Erbium-Doped Fiber (EDF) amplifier structure with a single pump source. The amplifier gain and noise figure variation with EDF pump power, input signal power and wavelengths have been investigated. The generated backward Amplified Spontaneous Emission (ASE) noise of the first amplifier stage is suppressed by using a tunable band-pass filter. The amplifier achieves a signal gain of 55 dB with low noise figure of 3.8 dB at -50 dBm input signal power. The amplifier gain shows significant improvement of 12.8 dB compared to amplifier structure without ASE suppression
56.6 dB high gain L-band EDFA utilizing short-length highly-doped erbium rare-earth material
In this paper, we experimentally investigate the performance of an efficient high gain L-band erbium-doped fiber (EDF) amplifier structure utilizing short-length highly-doped erbium rare-earth material with a single pump source. The amplifier gain and noise figure variation for different amplifier structures have been investigated. A filter is used to reduce the self-saturation effect and suppress the C-band amplified spontaneous emission (ASE) noise. The amplifier achieves a signal gain of 56.6 dB with a low noise figure of 4.8 dB at -50 dBm input signal power using only 8 m of EDF length. The amplifier gain shows significant improvement of 6 dB with C/L band coupler and 13 dB with tunable-band pass filter compared to amplifier structure without ASE suppression
DETERMINANTS OF LEADERSHIP STYLES ON ORGANIZATIONAL CULTURE TOWARDS ORGANIZATION PERFORMANCE IN ABU DHABI PUBLIC SECTOR: STRUCTURAL EQUATION MODELLING (SEM)
In this new economy, mobility of knowledge employees has become a major concern of the business organizations since organizations may lose the competitive advantage due to the shortness of talent. Thus, the purpose of this research is to assess the determinants of leadership styles on organizational culture towards organization performance in Abu Dhabi Public Sector. A total of 398 respondents were selected for the data analysis, where the ultimate step of data analysis is the employing appropriate analytical methods to understand and interpret the data collected. Prior to Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA), the Structural Equation Modelling (SEM) was conducted to check the hypothesis relationships of the variables to verify its factor structure. The findings of this study revealed that, strategic leadership style is positively related to organizational culture. Besides, laissez-faire leadership style is positively related to organizational culture, as well as autocratic leadership style is positively related to organizational culture. Result also indicated that, participative leadership style is positively related to organizational culture; transactional leadership style is positively related to organizational culture, transformational leadership style is positively related to organizational culture. Interestingly, the organizational culture is positively related to organization performance. Result also revealed that, strategic leadership style is positively related to organization performance; laissez-faire leadership style is positively related to organization performance. In addition, autocratic leadership style is positively related to organization performance; participative leadership style is positively related to organization performance. Then, transactional leadership style is positively related to organization performance. At the same time, transformational leadership style is positively related to organization performance. Besides that, it is also found that age is not related to organization performance, same goes to education. So, this research opens up some meticulous findings which will enhance the future research on the similar field. Article visualizations
Bridging the Gap: Social Networks and Professional Development in the Eyes of Prospective Science Teachers
Virtual social network platforms have rapidly become settings for cultivating various types of bonding, bridging, and building social capital. This promotes professional and personal relationships and has implications for our psychological wellness. Our qualitative study, which has taken place in the United Arab Emirates (UAE) and Oman, explored the perspectives of science teachers in training regarding the utilization of social networks for professional development (PD). We conducted 26 semi-structured interviews across both countries. Our results unveiled nuanced insights into the influence of social networks on the professional development of prospective science teachers, the challenges they face while using these means for networking, and how cultural norms and institutional factors impact learning, collaboration, and adoption of such virtual social systems. The findings suggest that social networks can serve as valuable tools for the professional development of prospective science teachers. Notably, there was a subtle divergence between the two groups. The UAE participants have emphasized global perspectives and valued insights into worldwide educational trends, whereas the Omani participants have appreciated the global perspective and prioritized local connections. Additionally, remarkable differences in technology access and infrastructure challenges between UAE and Oman teachers in training highlight the need for more equitable professional development opportunities. Emirati and Omani participants differ in their access to international educational trends and technology because of economic disparities. This could be translated into more resources for education and technological infrastructure, as the geographical location of the UAE as a global hub makes it easier to access global networks and trends. The implications of these findings point to the critical need for the effective use of social networks in the professional development of science teachers. Doi: 10.28991/ESJ-2024-08-01-014 Full Text: PD
In vitro studies on CNGRC-CPG2 fusion proteins for ligand-directed enzyme prodrug therapy for targeted cancer therapy
The sequence asparagine-glycine arginine (NGR), flanked by Cysteine (Cys) residues so as to form a disulfide-bridge (CNGRC), has previously been found to target and bind specifically to aminopeptidase N (APN), which is highly expressed on the surface of tumor cells. The goal of this study was to develop and evaluate the potential of fusion proteins carrying the CNGRC sequence linked to the enzyme carboxypeptidase G2 (CPG2) for targeted cancer therapy. We refer to this strategy as ligand-directed enzyme prodrug therapy (LDEPT). We constructed two forms of the CNGRC-CPG2 fusions, containing one or two copies of the cyclic NGR motif and designated CNGRC-CPG2 (X-CPG2) and CNGRC-CPG2-CNGRC (X-CPG2-X), respectively. binding assays of the purified constructs showed that both X-CPG2 and X-CPG2-X bound with high affinity to cancer cells expressing high levels of APN, compared to their binding to cells expressing low levels of APN. Further studies of the constructs to assess the therapeutic potential of LDEPT were carried out using cells expressing high and low levels of APN. Using methotrexate, it was demonstrated that cancer cell survival was significantly higher in the presence of the fusion proteins, due to the hydrolysis of this cytotoxic drug by CPG2. Conversely, when the prodrug ZD2767P was used, cancer cell killing was higher in the presence of the fused CPG2 constructs than in their absence, which is consistent with CPG2-mediated release of the cytotoxic drug from the prodrug. Furthermore, the doubly-fused CPG2 construct (X-CPG2-X) was significantly more effective than the singly-fused construct (X-CPG2)
Digital Wellbeing for All: Expanding Inclusivity to Embrace Diversity in Socio-Emotional Status
The ubiquity of information and communication technology contributed positively in enhancing lives, mainly in increasing productivity and economic growth, while their impact on life satisfaction and wellbeing has been a hidden cost. Digital media shall empower users to maximise their digital wellbeing, i.e. healthy and regulated relationship with technology. Similar to usability, people differ in their needs to achieve and maintain their digital wellbeing. A technology design shall be inclusive in how it helps users to increase their digital wellbeing and reduce possible harm. Typical inclusivity dimensions in Human-Computer Interaction research include gender, race, physical and cognitive abilities, with the aim of making the product usable by the wider possible user set. However, another range of inclusivity dimensions becomes prominent and that is the diversity in users' socio-emotional characteristics such as susceptibility to online pressure (technical and social), resilience and others. Such characteristics can be traits, e.g. introversion, or temporal status, e.g. being in a low mood. In this position paper, we are proposing digital wellbeing as a target for an inclusive design where technology designers need to anticipate and reduce the negative impact of their products and services on the wellbeing of users through considering their diverse socio-emotional status
Seamless tuning range based-on available gain bandwidth in multiwavelength Brillouin fiber laser.
We experimentally demonstrate a simple widely tunable multiwavelength Brillouin/Erbium fiber laser that can be tuned over the entire C-band, thereby greatly improving the tuning range limitation faced by the previous Brillouin-erbium fiber laser architectures. Tuning range of 39 nm from 1527 nm to 1566 nm, which is only limited by the amplification bandwidth of the erbium gain was successfully achieved. At Brillouin pump wavelength of 1550 nm and 1480 nm laser pump and Brillouin pump powers of 130 mW and 2 mW respectively, all the generated output channels have peak power above 0 dBm, with the first output channel having a peak power of 8.52 dBm. The experimental set up that consists of only 4 optical components, is simple, devoid of the complex structure employed previously to enhance the tunability and feedback mechanism normally associated with multiwavelength Brillouin-erbium fiber laser sources. The generated output channels are stable, rigidly separated by 10 GHz (0.08 nm)
The impact of super resolution on detecting COVID-19 from CT scans using VGG-16 based learning
With the recent outbreak of the novel Coronavirus (COVID-19), the importance of early and accurate diagnosis arises, as it directly affects mortality rates. Computed Tomography (CT) scans of the patients’ lungs is one of the diagnosis methods utilized in some countries, such as China. Manual inspection of CT scans can be a lengthy process, and may lead to inaccurate diagnosis. In this paper, a Deep Learning strategy based on VGG-16 is utilized with Transfer Learning for the purpose of binary classification of CT scans; Covid and NonCovid. Additionally, it is hypothesized in this study that Single Image Super Resolution (SISR) can boost the accuracy of the networks’ performance. This hypothesis is tested by following the training strategy with the original dataset as well as the same dataset scaled by a factor of ×2. Experimental results show that SISR has a positive effect on the overall training performance
KNOWLEDGE MANAGEMENT STRATEGIES AND ORGANIZATIONAL PERFORMANCE IN ABU DHABI: A STRUCTURAL EQUATION MODELING (SEM) APPROACH
The aim of this study is to measure the knowledge management strategies and organizational performance in Abu Dhabi utilizing a structural equation modeling (SEM) approach. The research method of this research is a solely quantitative method where the total sample size is considered 331 employing simple random sampling. For this research, the structural model exhibited the relationships among the variables. The findings reveal that, knowledge management structure is positively related to knowledge management strategy, same to knowledge management practice is positively related to knowledge management strategy. However, knowledge management structure was found not really positively related to organizational performance. Unexpectedly, knowledge management practice has not also found significant either in terms of positively related to organizational performance. On the other hand, knowledge management strategy is positively related to organizational performance as well as reciprocal relationship found between knowledge management structure and knowledge management practice. This research has contributed to the existing knowledge by providing an empirically validated model which could be used to predict the organizational performance as a whole. Article visualizations
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