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Prevalence and Demographic Distributions of Pre-Eclampsia among Pregnant Women at Ho Teaching Hospital
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作者 Adwoa Nyarko Joshua A. Kunfah +3 位作者 David Z. Kolbilla Collins Adombire Akayuure Jamilatu B. Kappiah Sylvanus Kampo 《Open Journal of Obstetrics and Gynecology》 2024年第4期621-636,共16页
Background: In Sub-Saharan Africa, pre-eclampsia remains a major health problem contributing to high rates of maternal mortality. Despite this condition having adverse effects on maternal and child health, its prevale... Background: In Sub-Saharan Africa, pre-eclampsia remains a major health problem contributing to high rates of maternal mortality. Despite this condition having adverse effects on maternal and child health, its prevalence and associated risk factors are still significant, especially in developing countries including Ghana. This study aimed to assess the prevalence and demographic distributions associated with pre-eclampsia among pregnant women at the Ho Teaching Hospital. Methods: A facility-based retrospective study was conducted by reviewing available data or hospital records of pregnant mothers admitted to the labor and maternity wards from January 2018 to December 2020. All pregnant women who were diagnosed with pre-eclampsia within this period were included in the study. The data were collected using a structured checklist. Results: 5609 data on pregnant women from 2018 to 2020 were recorded. Out of the 5609 data recorded, 314 pre-eclampsia cases were recorded giving an overall prevalence of 5.6%. The yearly prevalence for 2018, 2019, and 2020 were 4.6%, 5.6%, and 6.6%, respectively. The most recorded pre-eclampsia cases were seen among women within the age group of 18 - 24 years. The data showed that 112 (35.7%) of the pregnant women who had pre-eclampsia were nulliparous. Pre-eclampsia-associated maternal and fetal complications were;preterm delivery 221 (70.4%), intrauterine fetal death 62 (19.7%), eclampsia 9 (2.9%), HELLP syndrome 5 (1.6%) and maternal death 17 (5.4%). Associated factors of pre-eclampsia were parity, level of education, and occupation (p ≤ 0.05). Conclusion: The findings of this study showed a rising trend in the incidence of pre-eclampsia over the years at the Ho Teaching Hospital. Parity, level of education, and occupation were found to be associated with developing pre-eclampsia. 展开更多
关键词 PRE-ECLAMPSIA PREVALENCE Demographic distributions Risk Factors ANTENATAL MATERNAL
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Optical Modeling of Sea Salt Aerosols Using in situ Measured Size Distributions and the Impact of Larger Size Particles
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作者 Wushao LIN Lei BI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期1917-1935,共19页
Sea salt aerosols play a critical role in regulating the global climate through their interactions with solar radiation.The size distribution of these particles is crucial in determining their bulk optical properties.... Sea salt aerosols play a critical role in regulating the global climate through their interactions with solar radiation.The size distribution of these particles is crucial in determining their bulk optical properties.In this study,we analyzed in situ measured size distributions of sea salt aerosols from four field campaigns and used multi-mode lognormal size distributions to fit the data.We employed super-spheroids and coated super-spheroids to account for the particles’non-sphericity,inhomogeneity,and hysteresis effect during the deliquescence and crystallization processes.To compute the singlescattering properties of sea salt aerosols,we used the state-of-the-art invariant imbedding T-matrix method,which allows us to obtain accurate optical properties for sea salt aerosols with a maximum volume-equivalent diameter of 12μm at a wavelength of 532 nm.Our results demonstrated that the particle models developed in this study were successful in replicating both the measured depolarization and lidar ratios at various relative humidity(RH)levels.Importantly,we observed that large-size particles with diameters larger than 4μm had a substantial impact on the optical properties of sea salt aerosols,which has not been accounted for in previous studies.Specifically,excluding particles with diameters larger than 4μm led to underestimating the scattering and backscattering coefficients by 27%−38%and 43%−60%,respectively,for the ACE-Asia field campaign.Additionally,the depolarization ratios were underestimated by 0.15 within the 50%−70%RH range.These findings emphasize the necessity of considering large particle sizes for optical modeling of sea salt aerosols. 展开更多
关键词 sea salt aerosol particle size distribution LIDAR optical property
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Bivariate Analysis of Pollutants Monthly Maxima in Mexico City Using Extreme Value Distributions and Copula
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作者 Juan A. Vazquez-Morales Eliane R. Rodrigues Hortensia J. Reyes-Cervantes 《Journal of Environmental Protection》 2024年第7期796-826,共31页
In the present work, we are interested in studying the joint distributions of pairs of the monthly maxima of the pollutants used by the environmental authorities in Mexico City to classify the air quality in the metro... In the present work, we are interested in studying the joint distributions of pairs of the monthly maxima of the pollutants used by the environmental authorities in Mexico City to classify the air quality in the metropolitan area. In order to obtain the joint distributions a copula will be considered. Since we are analyzing the monthly maxima, the extreme value distributions of Weibull and Fréchet are taken into account. Using these two distributions as marginal distributions in the copula a Bayesian inference was made in order to estimate the parameters of both distributions and also the association parameters appearing in the copula model. The pollutants taken into account are ozone, nitrogen dioxide, sulphur dioxide, carbon monoxide, and particulate matter with diameters smaller than 10 and 2.5 microns obtained from the Mexico City monitoring network. The estimation was performed by taking samples of the parameters generated through a Markov chain Monte Carlo algorithm implemented using the software OpenBugs. Once the algorithm is implemented it is applied to the pairs of pollutants where one of the coordinates of the pair is ozone and the other varies on the set of the remaining pollutants. Depending on the pollutant and the region where they were collected, different results were obtained. Hence, in some cases we have that the best model is that where we have a Fréchet distribution as the marginal distribution for the measurements of both pollutants and in others the most suitable model is the one assuming a Fréchet for ozone and a Weibull for the other pollutant. Results show that, in the present case, the estimated association parameter is a good representation to the correlation parameters between the pair of pollutants analyzed. Additionally, it is a straightforward task to obtain these correlation parameters from the corresponding association parameters. 展开更多
关键词 COPULA Extreme Value distribution Bayesian Inference Air Pollution Mexico City
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Photoelectron momentum distributions of triatomic CO_(2)molecules by circularly polarized attosecond pulses
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作者 Si-Qi Zhang Jun Zhang +3 位作者 Xin-Yu Hao Jing Guo Aihua Liu Xue-Shen Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期220-225,共6页
Molecular-frame photoelectron momentum distributions(MF-PMDs)have been studied for imaging molecular structures.We investigate the MF-PMDs of CO_(2)molecules exposed to circularly polarized(CP)attosecond laser pulses ... Molecular-frame photoelectron momentum distributions(MF-PMDs)have been studied for imaging molecular structures.We investigate the MF-PMDs of CO_(2)molecules exposed to circularly polarized(CP)attosecond laser pulses bysolving the time-dependent Schrodinger equations based on the single-active-electron approximation frames.Results showthat high-frequency photons lead to photoelectron diffraction patterns,indicating molecular orbitals.These diffractionpatterns can be illustrated by the ultrafast photoionization models.However,for the driving pulses with 30 nm,a deviationbetween MF-PMDs and theoretically predicted results of the ultrafast photoionization models is produced because theCoulomb effect strongly influences the molecular photoionization.Meanwhile,the MF-PMDs rotate in the same directionas the helicity of driving laser pulses.Our results also demonstrate that the MF-PMDs in a CP laser pulse are the superpositionof those in the parallel and perpendicular linearly polarized cases.The simulations efficiently visualize molecularorbital geometries and structures by ultrafast photoelectron imaging.Furthermore,we determine the contribution of HOMOand HOMO-1 orbitals to ionization by varying the relative phase and the ratio of these two orbitals. 展开更多
关键词 molecular-frame photoelectron momentum distributions single-active-electron approximation frames ultrafast photoionization models
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Using Pearson’s System of Curves to Approximate the Distributions of the Difference between Two Correlated Estimates of Signal-to-Noise Ratios: The Cases of Bivariate Normal and Bivariate Lognormal Distributions
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作者 Mohamed M. Shoukri 《Open Journal of Statistics》 2024年第3期207-227,共21页
Background: The signal-to-noise ratio (SNR) is recognized as an index of measurements reproducibility. We derive the maximum likelihood estimators of SNR and discuss confidence interval construction on the difference ... Background: The signal-to-noise ratio (SNR) is recognized as an index of measurements reproducibility. We derive the maximum likelihood estimators of SNR and discuss confidence interval construction on the difference between two correlated SNRs when the readings are from bivariate normal and bivariate lognormal distribution. We use the Pearsons system of curves to approximate the difference between the two estimates and use the bootstrap methods to validate the approximate distributions of the statistic of interest. Methods: The paper uses the delta method to find the first four central moments, and hence the skewness and kurtosis which are important in the determination of the parameters of the Pearsons distribution. Results: The approach is illustrated in two examples;one from veterinary microbiology and food safety data and the other on data from clinical medicine. We derived the four central moments of the target statistics, together with the bootstrap method to evaluate the parameters of Pearsons distribution. The fitted Pearsons curves of Types I and II were recommended based on the available data. The R-codes are also provided to be readily used by the readers. 展开更多
关键词 Signal-to-Noise Ratio Bivariate distributions Bootstrap Methods Delta Method Pearson System of Curves
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Remaining Useful Life for Heavy-Duty Railway Cast Steel Knuckles Based on Crack Growth Behavior with Hypothetical Distributions
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作者 Chao Wang Tao Zhu +2 位作者 Bing Yang Shoune Xiao Guangwu Yang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第4期290-305,共16页
The current research on the integrity of critical structures of rail vehicles mainly focuses on the design stage,which needs an effective method for assessing the service state.This paper proposes a framework for pred... The current research on the integrity of critical structures of rail vehicles mainly focuses on the design stage,which needs an effective method for assessing the service state.This paper proposes a framework for predicting the remaining useful life(RUL)of in-service structures with and without visible cracks.The hypothetical distribution and delay time models were used to apply the equivalent crack growth life data of heavy-duty railway cast steel knuckles,which revealed the evolution characteristics of the crack length and life scores of the knuckle under different fracture failure modes.The results indicate that the method effectively predicts the RUL of service knuckles in different failure modes based on the cumulative failure probability curves for different locations and surface crack lengths.This study proposes an RUL prediction framework that supports the dynamic overhaul and state maintenance of knuckle fatigue cracks. 展开更多
关键词 Heavy-duty railway Cast steel knuckle Remaining useful life Fatigue crack growth Hypothetical distribution
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Spatiotemporal Distributions of Bacterioplankton Communities in the Qiantang River(Hangzhou Section),China
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作者 XU Jiaojiao ZHAO Li +4 位作者 LUKWAMBE Betina NICHOLAUS Regan ZHU Jinyong YANG Wen ZHENG Zhongming 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期1102-1114,共13页
The spatial and temporal distribution of bacterioplankton communities plays a vital role in understanding the ecological dynamics and health of aquatic ecosystems.In this study,we conducted a comprehensive investigati... The spatial and temporal distribution of bacterioplankton communities plays a vital role in understanding the ecological dynamics and health of aquatic ecosystems.In this study,we conducted a comprehensive investigation of the bacterioplankton communities in the Qiantang River(Hangzhou section).Water samples were collected quarterly from seven sites over a one-year period.Physical and chemical parameters,including dissolved oxygen(DO),water temperature(WT),chemical oxygen demand(COD),nitrite(NO_(2)^(-)),active phosphate(PO_(4)^(3-))and other indices were determined.In this study,theαdiversity,βdiversity and abundance differences of bacterial communities were investigated using 16S rRNA high-throughput sequencing analysis.The spatial and temporal distribution characteristics and main driving factors of the bacterioplankton community structure and diversity were discussed.The results showed that a total of 57 phyla were detected in the bacterioplankton community,among which Proteobacteria and Actinomycetes were the two dominant groups with the highest relative abundance.The results of PCoA based on Bray-Curtis distance showed that the sampling season had a slightly greater effect on the changes in bacterioplankton community structure in the Qiantang River.Mantel and partial Mantel test showed that environmental variables(Mantel r=0.6739,P<0.0001;partial Mantel r=0.507,P=0.0001)were more important than geographical distance(Mantel r=0.5322,P<0.001;partial Mantel r=0.1563,P=0.001).The distance attenuation model showed that there was significant distance attenuation in all four seasons,and the maximum limit of bacterial community diffusion was found in spring.RDA analysis showed that nine environmental factors,including COD,WT and DO,significantly affected community distribution(P<0.05).This study provides valuable insights into the spatial and temporal distribution characteristics of bacterioplankton communities,shedding light on their ecological roles in the Qiantang River.The information obtained can guide future research on the interactions between bacterioplankton and their environment,enabling the development of effective conservation strategies and sustainable management practices for aquatic ecosystems. 展开更多
关键词 Qiantang River bacterioplankton community spatial and temporal distribution 16S rRNA range attenuation
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Ion dynamics into different pore size distributions in supercapacitors under compression 被引量:1
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作者 João Pedro Aguiar dos Santos Cesar J.B.Pagan +4 位作者 Rafael Vicentini Reinaldo F.Teófilo Renato Beraldo Leonardo M.Da Silva Hudson Zanin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期110-119,I0004,共11页
Compressing supercapacitor(SCs)electrode is essential for improving the energy storage characteristics and minimizing ions’distance travel,faradaic reactions,and overall ohmic resistance.Studies comprising the ion dy... Compressing supercapacitor(SCs)electrode is essential for improving the energy storage characteristics and minimizing ions’distance travel,faradaic reactions,and overall ohmic resistance.Studies comprising the ion dynamics in SC electrodes under compression are still rare.So,the ionic dynamics of five aqueous electrolytes in electrodes under compression were studied in this work for tracking electrochemical and structural changes under mechanical stress.A superionic state is formed when the electrode is compressed until the micropores match the dimensions with the electrolyte’s hydrated ion sizes,which increases the capacitance.If excessive compression is applied,the accessible pore regions decrease,and the capacitance drops.Hence,as the studied hydrated ions have different dimensions,the match between ion/pore sizes differs.To the LiOH and NaClO4electrolytes,increasing the pressure from 60 to 120 and 100 PSI raised the capacitance from 13.5 to 35.2 F g^(-1)and 30.9 to 39.0 F g^(-1),respectively.So,the KOH electrolyte with the lowest and LiCl with the biggest combination of hydrated ion size have their point of maximum capacitance(39.5 and 36.7F g^(-1))achieved at 140 and 80 PSI,respectively.To LiCl and KCl electrolytes,overcompression causes a drop in capacitance higher than 23%. 展开更多
关键词 Mechanic compression Pore size distribution lon dynamics Activated carbon SUPERCAPACITORS
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Developing Weibull-based diameter distributions for the major coniferous species in Heilongjiang Province,China 被引量:1
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作者 Qila Sa Xingji Jin +1 位作者 Timo Pukkala Fengri Li 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1803-1815,共13页
Diameter distribution models play an important role in forest inventories,growth prediction,and management.The Weibull probability density function is widely used in forestry.Although a number of methods have been pro... Diameter distribution models play an important role in forest inventories,growth prediction,and management.The Weibull probability density function is widely used in forestry.Although a number of methods have been proposed to predict or recover the Weibull distribution,their applicability and predictive performance for the major tree species of China remain to be determined.Trees in sample plots of three even-aged coniferous species(Larix olgensis,Pinus sylvestris and Pinus koraiensis)were measured both in un-thinned and thinned stands to develop parameter prediction models for the Weibull probability density function.Ordinary least squares(OLS)and maximum likelihood regression(MLER),as well as cumulative distribution function regression(CDFR)were used,and their performance compared.The results show that MLER and CDFR were better than OLS in predicting diameter distributions of tree plantations.CDFR produced the best results in terms of fitting statistics.Based on the error statistics calculated for different age groups,CDFR was considered the most suitable method for developing prediction models for Weibull parameters in coniferous plantations. 展开更多
关键词 Parameter prediction Maximum likelihood regression Cumulative distribution function regression
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Tuning Solid Interfaces via Varying Electrolyte Distributions Enables High-Performance Solid-State Batteries 被引量:1
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作者 Linfeng Peng Chuang Yu +5 位作者 Ziqi Zhang Ruonan Xu Mengjun Sun Long Zhang Shijie Cheng Jia Xie 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期26-33,共8页
Solid/solid interface is the major challenge for high-performance solid-state batteries.Solid electrolytes(SEs)play a crucial role in the fabrication of effective interfaces in solid-state batteries.Herein,the electro... Solid/solid interface is the major challenge for high-performance solid-state batteries.Solid electrolytes(SEs)play a crucial role in the fabrication of effective interfaces in solid-state batteries.Herein,the electrolyte distribution with varied particle sizes is tuned to construct solid-state batteries with excellent performance at different operating temperatures.Solid-state batteries with the configuration S/L(small-sized SE in composite cathode and large-sized SE in electrolyte layer)show the best performance at room temperature(168 mA h g^(−1) at 0.2 C,retention of 99%,100 cycles)and−20°C(89 mA h g^(−1) at 0.05 C),while the configuration S/S displays better performance at elevated temperature.The superior performance of S/L battery is associated with faster lithium-ion dynamics due to the better solid/solid interface between active materials and electrolytes.Moreover,the inferior performance at 60℃is caused by the formation of voids and cracks in the electrolyte layer during cycling.In contrast,the S/S battery delivers superior performance at elevated operating temperature because of the integrated structure.This work confirms that tailoring electrolyte size has significant effect on fabricating all-climate solid-state batteries. 展开更多
关键词 electrochemical performance lithium argyrodite operating temperature size distribution solid-state batteries
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Natural variations and geographical distributions of seed carotenoids and chlorophylls in 1167 Chinese soybean accessions 被引量:1
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作者 Berhane S.GEBREGZIABHER ZHANG Sheng-rui +7 位作者 Muhammad AZAM QI Jie Kwadwo G.AGYENIM-BOATENG FENG Yue LIU Yi-tian LI Jing LI Bin SUN Jun-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第9期2632-2647,共16页
Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.This study investigated the variability in the concentrations of carotenoids a... Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.This study investigated the variability in the concentrations of carotenoids and chlorophylls and revealed their associations with other nutritional quality traits in a genetically diverse set of Chinese soybean accessions comprised of cultivars and landraces.Genotype,planting year,accession type,seed cotyledon color,and ecoregion of origin significantly influenced the accumulation of carotenoids and chlorophylls.The mean total carotenoid content was in the range of 8.15–14.72μg g–1 across the ecoregions.The total carotenoid content was 1.2-fold higher in the landraces than in the cultivars.Soybeans with green cotyledons had higher contents of carotenoids and chlorophylls than those with yellow cotyledons.Remarkably,lutein was the most abundant carotenoid in all the germplasms,ranging from 1.35–37.44μg g–1.Carotenoids and chlorophylls showed significant correlations with other quality traits,which will help to set breeding strategies for enhancing soybean carotenoids without affecting the other components.Collectively,our results demonstrate that carotenoids are adequately accumulated in soybean seeds,however,they are strongly influenced by genetic factors,accession type,and germplasm origin.We identified novel germplasms with the highest total carotenoid contents across the various ecoregions of China that could serve as the genetic materials for soybean carotenoid breeding programs,and thereby as the raw materials for food sectors,pharmaceuticals,and the cosmetic industry. 展开更多
关键词 accession type carotenoid CHLOROPHYLL ECOREGION geographical distribution Pearson’s correlation soybean(Glycine max L.Merrill)
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Proton pitch angle distributions in the Martian induced magnetosphere: A survey of Tianwen-1 Mars Ion and Neutral Particle Analyzer observations 被引量:1
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作者 TaiFeng Jin BinBin Ni +14 位作者 LingGao Kong AiBing Zhang Lei Li Song Fu Xing Cao WenYa Li BinBin Tang LiangHai Xie YiTeng Zhang ShuYue Pang XiaoTong Yun HengLe Du FuHao Qiao LiMin Wang JiJie Ma 《Earth and Planetary Physics》 CAS CSCD 2023年第5期533-539,共7页
The pitch angle distributions of ions and electrons can be affected by various processes;thus,they can serve as an important indicator of the physical mechanisms driving the dynamics of space plasmas.From observations... The pitch angle distributions of ions and electrons can be affected by various processes;thus,they can serve as an important indicator of the physical mechanisms driving the dynamics of space plasmas.From observations from the Mars Ion and Neutral Particle Analyzer onboard the Tianwen-1 orbiter,we calculated the pitch angle distributions of protons in the Martian induced magnetosphere by using information from the magnetohydrodynamically simulated magnetic field,and we statistically analyzed the spatial occurrence pattern of different types of pitch angle distributions.Even though no symmetrical features were seen in the dataset,we found the dominance of the field-aligned distribution type over the energy range from 188 to 6232 eV.Maps of the occurrence rate showed the preferential presence of a trapped-like distribution at the lower altitudes of the surveyed nightside region.Although our results are more or less restricted by the adopted magnetic field,they indicate the complexity of the near-Mars proton pitch angle distributions and infer the possibility of wave–particle interactions in the Martian induced magnetosphere. 展开更多
关键词 Martian plasma environment ion pitch angle distribution Tianwen-1 Mars Ion and Neutral Particle Analyzer(MINPA)
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Distributed Nash Equilibrium Seeking Strategies Under Quantized Communication 被引量:2
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作者 Maojiao Ye Qing-Long Han +2 位作者 Lei Ding Shengyuan Xu Guobiao Jia 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期103-112,共10页
This paper is concerned with distributed Nash equi librium seeking strategies under quantized communication. In the proposed seeking strategy, a projection operator is synthesized with a gradient search method to achi... This paper is concerned with distributed Nash equi librium seeking strategies under quantized communication. In the proposed seeking strategy, a projection operator is synthesized with a gradient search method to achieve the optimization o players' objective functions while restricting their actions within required non-empty, convex and compact domains. In addition, a leader-following consensus protocol, in which quantized informa tion flows are utilized, is employed for information sharing among players. More specifically, logarithmic quantizers and uniform quantizers are investigated under both undirected and connected communication graphs and strongly connected digraphs, respec tively. Through Lyapunov stability analysis, it is shown that play ers' actions can be steered to a neighborhood of the Nash equilib rium with logarithmic and uniform quantizers, and the quanti fied convergence error depends on the parameter of the quan tizer for both undirected and directed cases. A numerical exam ple is given to verify the theoretical results. 展开更多
关键词 CONSENSUS distributed Nash equilibrium seeking projected gradient play quantized communication
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FPGA-based position reconstruction method for neutron beam flux spatial distribution measurement in BNCT 被引量:1
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作者 Wei Jiang Ping Cao +5 位作者 Yi-Ming Wu Xian-Ke Liu Zhu-Jun Fang Zhi-Yong Zhang Bin Shi Jun Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期96-108,共13页
A new measurement method for the spatial distribution of neutron beam flux in boron neutron capture therapy(BNCT)is being developed based on the two-dimensional Micromegas detector.To address the issue of long process... A new measurement method for the spatial distribution of neutron beam flux in boron neutron capture therapy(BNCT)is being developed based on the two-dimensional Micromegas detector.To address the issue of long processing times in traditional offline position reconstruction methods,this paper proposes a field programmable gate array based online position reconstruction method utilizing the micro-time projection chamber principle.This method encapsulates key technical aspects:a self-adaptive serial link technique built upon the dynamical adjustment of the delay chain length,fast sorting,a coordinate-matching technique based on the mapping between signal timestamps and random access memory(RAM)addresses,and a precise start point-merging technique utilizing a circular combined RAM.The performance test of the selfadaptive serial link shows that the bit error rate of the link is better than 10-12 at a confidence level of 99%,ensuring reliable data transmission.The experiment utilizing the readout electronics and Micromegas detector shows a spatial resolution of approximately 1.4 mm,surpassing the current method’s resolution level of 5 mm.The beam experiment confirms that the readout electronics system can obtain the flux spatial distribution of neutron beams online,thus validating the feasibility of the position reconstruction method.The online position reconstruction method avoids traditional methods,such as bubble sorting and traversal searching,simplifies the design of the logic firmware,and reduces the time complexity from O(n2)to O(n).This study contributes to the advancement in measuring neutron beam flux for BNCT. 展开更多
关键词 Position reconstruction FPGA Readout electronics Neutron flux spatial distribution
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Empirical Bayesian Approach to Testing Homogeneity of Several Means of Inflated Poisson Distributions (IPD)
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作者 Mohamed M. Shoukri Maha Aleid 《Open Journal of Statistics》 2023年第3期285-299,共15页
Objectives: We introduce a special form of the Generalized Poisson Distribution. The distribution has one parameter, yet it has a variance that is larger than the mean a phenomenon known as “over dispersion”. We dis... Objectives: We introduce a special form of the Generalized Poisson Distribution. The distribution has one parameter, yet it has a variance that is larger than the mean a phenomenon known as “over dispersion”. We discuss potential applications of the distribution as a model of counts, and under the assumption of independence we will perform statistical inference on the ratio of two means, with generalization to testing the homogeneity of several means. Methods: Bayesian methods depend on the choice of the prior distributions of the population parameters. In this paper, we describe a Bayesian approach for estimation and inference on the parameters of several independent Inflated Poisson (IPD) distributions with two possible priors, the first is the reciprocal of the square root of the Poisson parameter and the other is a conjugate Gamma prior. The parameters of Gamma distribution are estimated in the empirical Bayesian framework using the maximum likelihood (ML) solution using nonlinear mixed model (NLMIXED) in SAS. With these priors we construct the highest posterior confidence intervals on the ratio of two IPD parameters and test the homogeneity of several populations. Results: We encountered convergence problem in estimating the hyperparameters of the posterior distribution using the NLMIXED. However, direct maximization of the predictive density produced solutions to the maximum likelihood equations. We apply the methodologies to RNA-SEQ read count data of gene expression values. 展开更多
关键词 distributions of Over-Dispersed Counts Lagrange Class of distributions Knowledge Transfer Gamma Prior Posterior Inference Wilson-Hilferty Transformation RNA_SEQ Read Counts Data
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Construction and Weight Distributions of Binary Linear Codes Based on Deep Holes
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作者 Yong Yang Wenwei Qiu 《Applied Mathematics》 2023年第10期684-695,共12页
Deep holes are very important in the decoding of generalized RS codes, and deep holes of RS codes have been widely studied, but there are few works on constructing general linear codes based on deep holes. Therefore, ... Deep holes are very important in the decoding of generalized RS codes, and deep holes of RS codes have been widely studied, but there are few works on constructing general linear codes based on deep holes. Therefore, we consider constructing binary linear codes by combining deep holes with binary BCH codes. In this article, we consider the 2-error-correcting binary primitive BCH codes and the extended codes to construct new binary linear codes by combining them with deep holes, respectively. Furthermore, three classes of binary linear codes are constructed, and then we determine the parameters and the weight distributions of these new binary linear codes. 展开更多
关键词 Linear Codes MacWilliams Equations Weight distribution Dual Codes Deep Holes Covering Radius
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Federated Learning Model for Auto Insurance Rate Setting Based on Tweedie Distribution 被引量:1
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作者 Tao Yin Changgen Peng +2 位作者 Weijie Tan Dequan Xu Hanlin Tang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期827-843,共17页
In the assessment of car insurance claims,the claim rate for car insurance presents a highly skewed probability distribution,which is typically modeled using Tweedie distribution.The traditional approach to obtaining ... In the assessment of car insurance claims,the claim rate for car insurance presents a highly skewed probability distribution,which is typically modeled using Tweedie distribution.The traditional approach to obtaining the Tweedie regression model involves training on a centralized dataset,when the data is provided by multiple parties,training a privacy-preserving Tweedie regression model without exchanging raw data becomes a challenge.To address this issue,this study introduces a novel vertical federated learning-based Tweedie regression algorithm for multi-party auto insurance rate setting in data silos.The algorithm can keep sensitive data locally and uses privacy-preserving techniques to achieve intersection operations between the two parties holding the data.After determining which entities are shared,the participants train the model locally using the shared entity data to obtain the local generalized linear model intermediate parameters.The homomorphic encryption algorithms are introduced to interact with and update the model intermediate parameters to collaboratively complete the joint training of the car insurance rate-setting model.Performance tests on two publicly available datasets show that the proposed federated Tweedie regression algorithm can effectively generate Tweedie regression models that leverage the value of data fromboth partieswithout exchanging data.The assessment results of the scheme approach those of the Tweedie regressionmodel learned fromcentralized data,and outperformthe Tweedie regressionmodel learned independently by a single party. 展开更多
关键词 Rate setting Tweedie distribution generalized linear models federated learning homomorphic encryption
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Rural-urban differences in distributions and determinants of facility delivery among women in Bangladesh
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作者 Jannatun Nayeem Christina Stennett +2 位作者 Atia Sharmeen Md Mahbub Hossain Gulam Muhammed Al Kibria 《Global Health Journal》 2023年第4期222-229,共8页
Introduction:The utilization of facility delivery is crucial to achieve sustainable development goals by reducing maternal and neonatal deaths.This study aimed to compare the distributions and determinants of childbir... Introduction:The utilization of facility delivery is crucial to achieve sustainable development goals by reducing maternal and neonatal deaths.This study aimed to compare the distributions and determinants of childbirth in health facilities in urban and rural regions of Bangladesh.Methods:Cross-sectional data from the 2017-2018 Bangladesh Demographic and Health Survey were analyzed.Multilevel logistic regression was applied.Results:A total of 4751 women were included in the analyses.Only 50%of childbirths took place in health facilities,63.4%and 44.6%in urban and rural regions,respectively.Overall,the odds of the association between facility delivery and the studied factors were similar.Multiparous women had significantly lower odds of facility delivery in both rural(adjusted odds ratio[AOR]=0.3,95%confidence interval[CI]:0.2 to 0.5)and urban(AOR=0.2,95%CI:0.1 to 0.5)regions.In both regions,women with higher education levels,highly educated husbands,antenatal care(ANC),and higher wealth indexes had significantly higher odds of facility delivery.Conclusion:Several common associated factors were identified.However,differences were observed regarding distributions of these factors.The differences in facility delivery utilization could result from lower ANC utilization,socioeconomic status,and transportation facilities in rural regions than urban regions;therefore,improving these conditions could increase facility delivery in these regions. 展开更多
关键词 BANGLADESH Facilitydelivery Determinants distributions URBAN RURAL CHILDBIRTH
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COMPARISON OF HOMOLOGIES AND AUTOMATIC EXTENSIONS OF INVARIANT DISTRIBUTIONS
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作者 陈阳洋 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1561-1570,共10页
Let G be a reductive Nash group,acting on a Nash manifold X.Let Z be a G-stable closed Nash submanifold of X and denote by U the complement of Z in X.Letχbe a character of G and denote by g the complexified Lie algeb... Let G be a reductive Nash group,acting on a Nash manifold X.Let Z be a G-stable closed Nash submanifold of X and denote by U the complement of Z in X.Letχbe a character of G and denote by g the complexified Lie algebra of G.We give a sufficient condition for the natural linear map H_(k)(g,S(U)×χ)→H_k(g,S(X)×χ)between the Lie algebra homologies of Schwartz functions to be an isomorphism.For k=0,by considering the dual,we obtain the automatic extensions of g-invariant(twisted by-χ)Schwartz distributions. 展开更多
关键词 Schwartz functions Lie algebra homology Hausdorffness Schwartz distributions automatic extensions
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Synergetic optimization operation method for distribution network based on SOP and PV 被引量:1
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作者 Lei Chen Ning Zhang +4 位作者 Xingfang Yang Wei Pei Zhenxing Zhao Yinan Zhu Hao Xiao 《Global Energy Interconnection》 EI CSCD 2024年第2期130-141,共12页
The integration of distributed generation brings in new challenges for the operation of distribution networks,including out-of-limit voltage and power flow control.Soft open points(SOP)are new power electronic devices... The integration of distributed generation brings in new challenges for the operation of distribution networks,including out-of-limit voltage and power flow control.Soft open points(SOP)are new power electronic devices that can flexibly control active and reactive power flows.With the exception of active power output,photovoltaic(PV)devices can provide reactive power compensation through an inverter.Thus,a synergetic optimization operation method for SOP and PV in a distribution network is proposed.A synergetic optimization model was developed.The voltage deviation,network loss,and ratio of photovoltaic abandonment were selected as the objective functions.The PV model was improved by considering the three reactive power output modes of the PV inverter.Both the load fluctuation and loss of the SOP were considered.Three multi-objective optimization algorithms were used,and a compromise optimal solution was calculated.Case studies were conducted using an IEEE 33-node system.The simulation results indicated that the SOP and PVs complemented each other in terms of active power transmission and reactive power compensation.Synergetic optimization improves power control capability and flexibility,providing better power quality and PV consumption rate. 展开更多
关键词 Synergetic optimization Soft open point(SOP) Photovoltaic(PV) distribution network
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