This study develops an Enhanced Threshold Based Energy Detection approach(ETBED)for spectrum sensing in a cognitive radio network.The threshold identification method is implemented in the received signal at the second...This study develops an Enhanced Threshold Based Energy Detection approach(ETBED)for spectrum sensing in a cognitive radio network.The threshold identification method is implemented in the received signal at the secondary user based on the square law.The proposed method is implemented with the signal transmission of multiple outputs-orthogonal frequency division multiplexing.Additionally,the proposed method is considered the dynamic detection threshold adjustments and energy identification spectrum sensing technique in cognitive radio systems.In the dynamic threshold,the signal ratio-based threshold is fixed.The threshold is computed by considering the Modified Black Widow Optimization Algorithm(MBWO).So,the proposed methodology is a combination of dynamic threshold detection and MBWO.The general threshold-based detection technique has different limitations such as the inability optimal signal threshold for determining the presence of the primary user signal.These limitations undermine the sensing accuracy of the energy identification technique.Hence,the ETBED technique is developed to enhance the energy efficiency of cognitive radio networks.The projected approach is executed and analyzed with performance and comparison analysis.The proposed method is contrasted with the conventional techniques of theWhale Optimization Algorithm(WOA)and GreyWolf Optimization(GWO).It indicated superior results,achieving a high average throughput of 2.2 Mbps and an energy efficiency of 3.8,outperforming conventional techniques.展开更多
Marriage is one of the valued institutions in the traditional African society. Incidentally, it has its own challenges. When a young man or woman gets to a certain age and he/she is not married, society frowns at it. ...Marriage is one of the valued institutions in the traditional African society. Incidentally, it has its own challenges. When a young man or woman gets to a certain age and he/she is not married, society frowns at it. Thus, many couples enter into marriage relationships with a lot of excitements and expectations. However, losing one＇s spouse to death robs one of all these excitements and expectations and exposes the bereaved spouse to some dehumanizing challenges. These challenges are mostly experienced by women in the Eastern Region of Nigeria. These women are subjected to dehumanizing practices which are socially accepted in the region. This paper attempts a comparative study of some of the practices imposed on widows in Eastern Nigeria. A sample of 200 participants was purposively selected from two states in the Eastern Region of Nigeria. The study adopted the qualitative research method. Thus, the analysis was made using descriptive method. The study showed that these inhuman traditional practices in Eastern Nigeria are initiated and perpetrated by the kinsmen （Umunna and Umuada）. It also showed that the widowhood treatment is meted out on all widows, but the severity or less severity of these treatments are dependent on the socio-economic and other attributes of the widow. Finally, recommendations were made, which include the need to protect the fundamental rights of widows and their children.展开更多
The optimizationfield has grown tremendously,and new optimization techniques are developed based on statistics and evolutionary procedures.There-fore,it is necessary to identify a suitable optimization technique for a...The optimizationfield has grown tremendously,and new optimization techniques are developed based on statistics and evolutionary procedures.There-fore,it is necessary to identify a suitable optimization technique for a particular application.In this work,Black Widow Optimization(BWO)algorithm is intro-duced to minimize the cost functions in order to optimize the Multi-Area Economic Dispatch(MAED).The BWO is implemented for two different-scale test systems,comprising 16 and 40 units with three and four areas.The performance of BWO is compared with the available optimization techniques in the literature to demonstrate the strategy’s efficacy.Results show that the optimized cost for four areas with 16 units is found to be 7336.76$/h,whereas it is 121,589$/h for four areas with 40 units using BWO.It is also noted that optimization algo-rithms other than BWO require higher cost value.The best-optimized solution for emission is achieved at 9.2784e+06 tones/h,and it is observed that there is a considerable difference between the worst and the best values.Also,the suggested technique is implemented for large-scale test systems successfully with high precision,and rapid convergence occurs in MAED.展开更多
Chinese poetry has exerted a great influence on American modernist poets,especially on William Carlos Williams(1883-1963).William Carlos Williams’The Widow’s Lament in Springtime shares some connections with Chinese...Chinese poetry has exerted a great influence on American modernist poets,especially on William Carlos Williams(1883-1963).William Carlos Williams’The Widow’s Lament in Springtime shares some connections with Chinese Boudoir poems in theme,image,and technique.This paper tends to discuss the influence of Chinese Boudoir poems on William Carlos Williams based on his creating of The Widow’s Lament in Springtime,which provides a new perspective for studying the communication of Chinese and American poetry.展开更多
Enhancing the accuracy of real-time ship roll prediction is crucial for maritime safety and operational efficiency.To address the challenge of accurately predicting the ship roll status with nonlinear time-varying dyn...Enhancing the accuracy of real-time ship roll prediction is crucial for maritime safety and operational efficiency.To address the challenge of accurately predicting the ship roll status with nonlinear time-varying dynamic characteristics,a real-time ship roll prediction scheme is proposed on the basis of a data preprocessing strategy and a novel stochastic trainer-based feedforward neural network.The sliding data window serves as a ship time-varying dynamic observer to enhance model prediction stability.The variational mode decomposition method extracts effective information on ship roll motion and reduces the non-stationary characteristics of the series.The energy entropy method reconstructs the mode components into high-frequency,medium-frequency,and low-frequency series to reduce model complexity.An improved black widow optimization algorithm trainer-based feedforward neural network with enhanced local optimal avoidance predicts the high-frequency component,enabling accurate tracking of abrupt signals.Additionally,the deterministic algorithm trainer-based neural network,characterized by rapid processing speed,predicts the remaining two mode components.Thus,real-time ship roll forecasting can be achieved through the reconstruction of mode component prediction results.The feasibility and effectiveness of the proposed hybrid prediction scheme for ship roll motion are demonstrated through the measured data of a full-scale ship trial.The proposed prediction scheme achieves real-time ship roll prediction with superior prediction accuracy.展开更多
A distributed generation network could be a hybrid power system that includes wind-diesel power generation based on induction generators(IGs)and synchronous generators(SGs).The main advantage of these systems is the p...A distributed generation network could be a hybrid power system that includes wind-diesel power generation based on induction generators(IGs)and synchronous generators(SGs).The main advantage of these systems is the possibility of using renewable energy in their structures.The most important challenge is to design the voltage-control loop with the frequency-control loop to obtain optimal responses for voltage and frequency deviations.In this work,the voltage-control loop is designed by an automatic voltage regulator.A linear model of the hybrid system has also been developed with coordinated voltage and frequency control.Dynamic frequency response and voltage deviations are compared for different load disturbances and different reactive loads.The gains of the SG and the static volt-ampere reactive compensator(SVC)controllers in the IG terminal are calculated using the Black Widow Optimization(BWO)algorithm to insure low frequency and voltage deviations.The BWO optimization algorithm is one of the newest and most powerful optimization methods to have been introduced so far.The results showed that the BWO algorithm has a good speed in solving the proposed objective function.A 22%improvement in time adjustment was observed in the use of an optimal SVC.Also,an 18%improvement was observed in the transitory values.展开更多
Located on Dongshan Island, off the coast of Fujian province, is a typical rural village called Tongbo. On May 10, 1950, 147 men were abducted by the KMT army on its way to Taiwan. Since a majority of the men were alr...Located on Dongshan Island, off the coast of Fujian province, is a typical rural village called Tongbo. On May 10, 1950, 147 men were abducted by the KMT army on its way to Taiwan. Since a majority of the men were already married, overnight, their wives became ＂widows,＂ and most would remain so for the rest of their lives. Consequently, Tongbo village became more widely known as Widow Village. The first objective of this paper is to document the tragic experiences of men and women in Tongbo village, focusing on these forced separations in 1950, the possibility of reunion after 1987, and the struggle to cope with the difficulties in between. The second objective of this paper is to argue that while heartbreaking, the experiences of this village are not extraordinary in the context of the Chinese Civil War. What made the men and women in Tongbo extraordinary is not their collective suffering, but how these villagers suffered less, not more, than in many other places, because of the actions of three key figures.展开更多
文摘This study develops an Enhanced Threshold Based Energy Detection approach(ETBED)for spectrum sensing in a cognitive radio network.The threshold identification method is implemented in the received signal at the secondary user based on the square law.The proposed method is implemented with the signal transmission of multiple outputs-orthogonal frequency division multiplexing.Additionally,the proposed method is considered the dynamic detection threshold adjustments and energy identification spectrum sensing technique in cognitive radio systems.In the dynamic threshold,the signal ratio-based threshold is fixed.The threshold is computed by considering the Modified Black Widow Optimization Algorithm(MBWO).So,the proposed methodology is a combination of dynamic threshold detection and MBWO.The general threshold-based detection technique has different limitations such as the inability optimal signal threshold for determining the presence of the primary user signal.These limitations undermine the sensing accuracy of the energy identification technique.Hence,the ETBED technique is developed to enhance the energy efficiency of cognitive radio networks.The projected approach is executed and analyzed with performance and comparison analysis.The proposed method is contrasted with the conventional techniques of theWhale Optimization Algorithm(WOA)and GreyWolf Optimization(GWO).It indicated superior results,achieving a high average throughput of 2.2 Mbps and an energy efficiency of 3.8,outperforming conventional techniques.
文摘Marriage is one of the valued institutions in the traditional African society. Incidentally, it has its own challenges. When a young man or woman gets to a certain age and he/she is not married, society frowns at it. Thus, many couples enter into marriage relationships with a lot of excitements and expectations. However, losing one＇s spouse to death robs one of all these excitements and expectations and exposes the bereaved spouse to some dehumanizing challenges. These challenges are mostly experienced by women in the Eastern Region of Nigeria. These women are subjected to dehumanizing practices which are socially accepted in the region. This paper attempts a comparative study of some of the practices imposed on widows in Eastern Nigeria. A sample of 200 participants was purposively selected from two states in the Eastern Region of Nigeria. The study adopted the qualitative research method. Thus, the analysis was made using descriptive method. The study showed that these inhuman traditional practices in Eastern Nigeria are initiated and perpetrated by the kinsmen （Umunna and Umuada）. It also showed that the widowhood treatment is meted out on all widows, but the severity or less severity of these treatments are dependent on the socio-economic and other attributes of the widow. Finally, recommendations were made, which include the need to protect the fundamental rights of widows and their children.
文摘The optimizationfield has grown tremendously,and new optimization techniques are developed based on statistics and evolutionary procedures.There-fore,it is necessary to identify a suitable optimization technique for a particular application.In this work,Black Widow Optimization(BWO)algorithm is intro-duced to minimize the cost functions in order to optimize the Multi-Area Economic Dispatch(MAED).The BWO is implemented for two different-scale test systems,comprising 16 and 40 units with three and four areas.The performance of BWO is compared with the available optimization techniques in the literature to demonstrate the strategy’s efficacy.Results show that the optimized cost for four areas with 16 units is found to be 7336.76$/h,whereas it is 121,589$/h for four areas with 40 units using BWO.It is also noted that optimization algo-rithms other than BWO require higher cost value.The best-optimized solution for emission is achieved at 9.2784e+06 tones/h,and it is observed that there is a considerable difference between the worst and the best values.Also,the suggested technique is implemented for large-scale test systems successfully with high precision,and rapid convergence occurs in MAED.
文摘Chinese poetry has exerted a great influence on American modernist poets,especially on William Carlos Williams(1883-1963).William Carlos Williams’The Widow’s Lament in Springtime shares some connections with Chinese Boudoir poems in theme,image,and technique.This paper tends to discuss the influence of Chinese Boudoir poems on William Carlos Williams based on his creating of The Widow’s Lament in Springtime,which provides a new perspective for studying the communication of Chinese and American poetry.
基金supported by the National Natural Science Foundation of China(Grant Nos.52231014 and 52271361)the Natural Science Foundation of Guangdong Province of China(Grant No.2023A1515010684).
文摘Enhancing the accuracy of real-time ship roll prediction is crucial for maritime safety and operational efficiency.To address the challenge of accurately predicting the ship roll status with nonlinear time-varying dynamic characteristics,a real-time ship roll prediction scheme is proposed on the basis of a data preprocessing strategy and a novel stochastic trainer-based feedforward neural network.The sliding data window serves as a ship time-varying dynamic observer to enhance model prediction stability.The variational mode decomposition method extracts effective information on ship roll motion and reduces the non-stationary characteristics of the series.The energy entropy method reconstructs the mode components into high-frequency,medium-frequency,and low-frequency series to reduce model complexity.An improved black widow optimization algorithm trainer-based feedforward neural network with enhanced local optimal avoidance predicts the high-frequency component,enabling accurate tracking of abrupt signals.Additionally,the deterministic algorithm trainer-based neural network,characterized by rapid processing speed,predicts the remaining two mode components.Thus,real-time ship roll forecasting can be achieved through the reconstruction of mode component prediction results.The feasibility and effectiveness of the proposed hybrid prediction scheme for ship roll motion are demonstrated through the measured data of a full-scale ship trial.The proposed prediction scheme achieves real-time ship roll prediction with superior prediction accuracy.
文摘A distributed generation network could be a hybrid power system that includes wind-diesel power generation based on induction generators(IGs)and synchronous generators(SGs).The main advantage of these systems is the possibility of using renewable energy in their structures.The most important challenge is to design the voltage-control loop with the frequency-control loop to obtain optimal responses for voltage and frequency deviations.In this work,the voltage-control loop is designed by an automatic voltage regulator.A linear model of the hybrid system has also been developed with coordinated voltage and frequency control.Dynamic frequency response and voltage deviations are compared for different load disturbances and different reactive loads.The gains of the SG and the static volt-ampere reactive compensator(SVC)controllers in the IG terminal are calculated using the Black Widow Optimization(BWO)algorithm to insure low frequency and voltage deviations.The BWO optimization algorithm is one of the newest and most powerful optimization methods to have been introduced so far.The results showed that the BWO algorithm has a good speed in solving the proposed objective function.A 22%improvement in time adjustment was observed in the use of an optimal SVC.Also,an 18%improvement was observed in the transitory values.
文摘Located on Dongshan Island, off the coast of Fujian province, is a typical rural village called Tongbo. On May 10, 1950, 147 men were abducted by the KMT army on its way to Taiwan. Since a majority of the men were already married, overnight, their wives became ＂widows,＂ and most would remain so for the rest of their lives. Consequently, Tongbo village became more widely known as Widow Village. The first objective of this paper is to document the tragic experiences of men and women in Tongbo village, focusing on these forced separations in 1950, the possibility of reunion after 1987, and the struggle to cope with the difficulties in between. The second objective of this paper is to argue that while heartbreaking, the experiences of this village are not extraordinary in the context of the Chinese Civil War. What made the men and women in Tongbo extraordinary is not their collective suffering, but how these villagers suffered less, not more, than in many other places, because of the actions of three key figures.
