This paper investigates the observation problem for a class of MIMO non uniformly observable systems in the presence of sampled and delayed outputs. A high gain observer is first designed for the ...delay-free and continuous output measurement case. The observer gain involves the resolution of an appropriate Lyapunov differential equation allowing to show that the underlying observation error converges exponentially to zero under a well defined persistent excitation condition. This observer is then redesigned to cope with the output sampling process as well as the output delay thanks to an appropriate cascade structure composed of a set of dynamical subsystems. The first subsystem in the cascade is an impulsive continuous–discrete time observer which provides the estimation of the delayed state and each remaining subsystem in the cascade is a predictor which estimates the state over a small horizon equal to a fraction of the time delay in such a way that the state of the last predictor is an estimate of the system actual state. The exponential convergence to zero of the observation error related to the cascade observer is established for arbitrarily long delays provided that the maximum value of the sampling partition diameter is lower than a certain given bound. Simulations results are given to highlight the performance and the main properties of the proposed cascade observer.
This research is based on the study (the knowledge of the environment and its representation in the results of the students of the technical education department) and the research includes four ...chapters, the first chapter (the problem of the research, its importance, its purpose, its limits, and the terms contained in the title of the research), the second chapter included the theoretical framework and the previous studies, which included the theoretical framework of the discussion about reading awareness and ended with a set of indicators, while the third chapter included the research procedures, which included the research complex, which amounted to (50) of the results of the students of the technical education section of the subject manual work, (3) actions were selected in a deliberate manner, then the research tool, and statistical methods and sample analysis, while the fourth chapter included research results, conclusions, and proposals, and the researcher reached a sentence of conclusions; borrowing neglected materials from the environment to produce artistic works that are characterized by beauty is an indication of the students' possession of a level of awareness towards their environment.
The current study investigates the efficiency of banks in Saudi Arabia in terms of technical change and change in total productivity. The study considers ten banks listed on Tadawul as a sample from ...2016 to 2021. The Malmquist Data Envelopment Analysis (Malmquist DEA) model is employed to measure banks’ efficiency. Customer deposits and balances with other banks and financial institutions are inputs, while the operating profit and net income are outputs to measure efficiency. The results of efficiency report that most of the Saudi Arabian banks are considerably efficient, while some are marginally efficient. The technical change report results show that Saudi Arabia’s banks are enthusiastic about adopting new technologies that lead to their growth. Further, the results of the change in total productivity show great dynamism among the Saudi Arabian banks to become more productive, which ultimately leads to a more remarkable performance. The study results demonstrate the good performance of Saudi Arabian banks; however, very few banks are marginally efficient in terms of efficiency change. Therefore, the study supports the established hypothesis that there is a significant change in the technical efficiency and total productivity of Saudi Arabian banks. AcknowledgmentThe author(s) acknowledge that the Deanship of Scientific Research supports the current project at Prince Sattam Bin Abdulaziz University under research project number 2022/02/20810.
Improving water-use efficiency (WUE) is a crucial way of achieving green industrial production and sustainable development. Applying an improved Super-slacks-based measure model with undesirable ...outputs, this paper investigates industrial WUE in mainland China. The results show that: (1) Industrial WUE in China is improving with the efficiency value increasing from 0.9874 to 0.9962 in 2012–2015. (2) The regions of water absolute scarcity and the vulnerability show the highest industry-related WUE, whereas the water stressed region, water scarce region, and water abundant region failed to achieve efficiency during the observation period. (3) The overall index value using the conventional model was higher than that of the improved model, indicating the need for a more reasonable water-use structure and environmentally friendly discharge structure. This study provides a new perspective for measuring industrial WUE and advances related studies by (1) incorporating the actual structure of water used and wastewater discharged with weights assigned to input and output slacks according to marginal use cost of water and marginal treatment cost of wastewater; and (2) adding realistic constraints on the amount of water used and wastewater discharged to the model. The estimated provinces in mainland China can adjust their industrial water-use structures and wastewater-discharge structures based on the results of this study, and thus improve the industrial WUE.
•An improved Slacks-based measure is applied for assessing water-use efficiency.•Importance of input and output indicators are distinguished based on reality.•Feasible region of the model is reconstructed with additional constraints added.•Super-SBM model is applied for full ranking of decision making units.
For area reasons, NMOS transistors are preferred over PMOS for the pull-up path in gate drivers. Bootstrapping has to ensure sufficient NMOS gate overdrive. Especially in high-current gate drivers ...with large transistors, the bootstrap capacitor is too large for integration. This paper proposes three options of fully integrated bootstrap circuits. The key idea is that the main bootstrap capacitor is supported by a second bootstrap capacitor, which is charged to a higher voltage and ensures high charge allocation when the driver turns on. A capacitor sizing guideline and the overall driver implementation including a suitable charge pump for permanent driver activation is provided. A linear regulator is used for bootstrap supply and it also compensates the voltage drop of the bootstrap diode. Measurements from a testchip in 180 nm high-voltage BiCMOS confirm the benefit of high-voltage charge storing. The fully integrated bootstrap circuit with two stacked 75.8 pF and 18.9 pF capacitors results in an expected voltage dip of lower than 1 V. Both bootstrap capacitors require 70% less area compared to a conventional bootstrap circuit. Besides drivers, the proposed bootstrap can also be directly applied to power stages to achieve fully integrated switched mode power supplies or class-D output stages.
Background and aim: Librarians, as practitioners of Library and Information Science (LIS), by playing various roles, can contribute to the promotion of research and expansion of human knowledge. The ...aim of the present study was to investigate librarians' scientific publications indexed in the Scopus database between 2016 and 2020 using the scientometric approach. Materials and methods: The present study, which was conducted using a scientometric approach, is descriptive in terms of data collection and applied in terms of the objective. The research population was all articles indexed in the Scopus database in 2016-2020 in which the word "librarian" is included in at least one of the authors’ organizational affiliations. The number of these articles amounted to 2207 after review and screening by the researchers. Findings: In general, librarians accounted for 1.5% of the worldwide scientific production in the field of LIS. Librarians were the first, second or third author in more than 60% of the articles analyzed. Totally, 61% of the articles by librarians were published in non-LIS disciplines such as biological sciences, medicine, and computer science, and the chi-square test showed that the participation of librarians was significantly higher in non-LIS disciplines than in LIS disciplines (p<0.001). A closer examination of the articles indexed by librarians in the Scopus database in the LIS subject area showed that scientometrics, library services, databases, archives, and knowledge management were the most interesting topics for librarians with a frequency of 134, 131, 84, 75 and 59 articles, respectively. Conclusion: Librarians as research assistants have made an important contribution to the writing of articles from non-LIS fields in recent years. Moreover, scientometrics has been one of the main topics of their research in the LIS field.
The subject of this work is optimization of outputs of L-band high power microwave tubes. These outputs are constructed as coaxial-to-waveguide transitions with a vacuum barrier in a form of glass or ...ceramic cup. The goal of optimization is to obtain sufficiently low reflection loss in the predefined frequency band and to avoid so called hot spots caused by excessive dissipation of microwave power in parts of the cup. Electromagnetic simulator has been applied to model the behavior of the optimized transition and to propose its optimum shape. The proposed solutions were verified by Z.E. Lamina SA in prototypes of high power (pulsed 600 kW) amplitrons and are to be used in manufacturing practice.
In recent years, the application of wireless power transfer (WPT) has drawn vast attention with the advantage of canceling electrical wires. Some electronic devices require various voltage levels for ...driving and control systems concurrently. Therefore, in this letter, a new multiple regulatable output rectifier is proposed for the WPT application to meet the charging demands. The proposed rectifier integrates the buck converters, and then, 4+ n semiconductor devices and n inductors are utilized to achieve 1+ n output channels, which share a common ground. Besides, the inductor current ripples of the proposed rectifier are lower compared to those of the traditional buck converters. A 300-W prototype with 48, 18, and 12 V output voltages is built. The experimental results verify that the outputs are independently regulatable, and the overall efficiency is higher than 90.08%.
In this paper, we propose the concept of carbon unlocking efficiency based on carbon lock-in. Supported by the “Techno-Institutional Complex” theory, we measure the industrial carbon unlocking ...efficiency (ICUE) of 30 Chinese provinces and analyze its spatial and temporal jump probabilities through spatial Markov chains, and finally identify and discuss the influencing factors through the GTWR model. We found that the ICUE of each province in China follows a decreasing distribution from east to central to west, with Shanghai, Beijing, and Guangdong having the highest ICUEs among all provinces and cities; although the overall ICUE converges to a higher level in the long run, there is still a certain predatory effect of developed regions on less developed regions in the short term, and the intensification of market competition may adversely affect the growth of ICUE in the lagging regions. The results of GTWR show that factors such as energy use efficiency, FDI, and industrial enterprise size mainly promote ICUE growth, and energy structure mainly shows negative effects on ICUE of each province, while factors such as economic efficiency, R&D intensity, ownership structure, marketization level, share of high-tech industries, and industrial upgrading show obvious spatial heterogeneity, and different regions need to adopt different policy instruments for their strengths and weaknesses. These research results have important policy guidance implications for accelerating the process of industrial carbon unlocking in each region.
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•Propose an industrial carbon unlocking efficiency measurement system•The driving factors of ICUE are investigated using GTWR.•Competition among provinces leads to highly uncoordinated ICUE development•The influencing factors show significant spatial and temporal heterogeneity
Probabilistic forecasting of solar photovoltaic (PV) generation is critical for stochastic or robust optimisation-based power system dispatch. This study proposes a randomised learning-based hybrid ...ensemble (RLHE) model to construct the prediction intervals of probabilistic PV forecasting. Three different randomised learning algorithms, namely extreme learning machine, randomised vector functional link, and stochastic configuration network, are ensembled as a hybrid forecasting model. Besides, bootstrap is used as the ensemble learning framework to increase the diversity of training samples. For each algorithm, a decision-making rule is designed to evaluate the credibility of the individual outputs and the incredible ones are discarded at the output aggregation step. The weight coefficients of the aggregated outputs of the three algorithms are then optimised to compute the final point forecast results. Based on the point forecast results, the prediction intervals are constructed considering both model misspecification uncertainty and data noise uncertainty. The variance in model misspecification uncertainty is directly calculated with the individual outputs and the variance in data noise uncertainty is separately trained with an RLHE model. The proposed method is tested with an open dataset and compared with several benchmarking approaches.
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