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Forecasting strong subsequent earthquakes in Japan using an improved version of NESTORE machine learning algorithm
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作者 S.Gentili G.D.Chiappetta +2 位作者 G.Petrillo P.Brondi J.Zhuang 《Geoscience Frontiers》 2025年第3期205-222,共18页
In this study,the advanced machine learning algorithm NESTORE(Next Strong Related Earthquake)was applied to the Japan Meteorological Agency catalog(1973-2024).It calculates the probability that the aftershocks will re... In this study,the advanced machine learning algorithm NESTORE(Next Strong Related Earthquake)was applied to the Japan Meteorological Agency catalog(1973-2024).It calculates the probability that the aftershocks will reach or exceed a magnitude equal to the magnitude of the mainshock minus one and classifies the clusters as type A or type B,depending on whether this condition is met or not.It has been shown useful in the tests in Italy,western Slovenia,Greece,and California.Due to Japan’s high and complex seismic activity,new algorithms were developed to complement NESTORE:a hybrid cluster identification method,which uses both ETAS-based stochastic declustering and deterministic graph-based selection,and REPENESE(RElevant features,class imbalance PErcentage,NEighbour detection,SElection),an algorithm for detecting outliers in skewed class distributions,which takes in account if one class has a larger number of samples with respect to the other(class imbalance).Trained with data from 1973 to 2004(7 type A and 43 type B clusters)and tested from 2005 to 2023(4 type A and 27 type B clusters),the method correctly forecasted 75%of A clusters and 96%of B clusters,achieving a precision of 0.75 and an accuracy of 0.94 six hours after the mainshock.It accurately classified the 2011 Tōhoku event cluster.Near-real-time forecasting was applied to the sequence after the April 17,2024 M6.6 earthquake in Shikoku,correctly classifying it as a“Type B cluster”.These results highlight the potential for the forecasting of strong aftershocks in regions with high seismicity and class imbalance,as evidenced by the high recall,precision and accuracy values achieved in the test phase. 展开更多
关键词 Machine learning Cluster identification ETASS trong aftershock JAPAN Outliers detection
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Statistical Monitoring Report on the Process of Building a Well-off Society in an All-round Way in China in 2011 被引量:1
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作者 Institute of Statistical Science,National Bureau of Statistics of China 《China Population Today》 2012年第3期26-39,共14页
Building a well-off society in an all-round way is the goal put forward at the 16th CPC National Congress for the first two decades of this century.According to 'Statistical Monitoring Program on Building a Well-o... Building a well-off society in an all-round way is the goal put forward at the 16th CPC National Congress for the first two decades of this century.According to 'Statistical Monitoring Program on Building a Well-off Society' [1], Institute of Statistical Science,National Bureau of Statistics of China and local statistics research departments had conducted statistical monitoring for the process of building a well-off society in an all-round way from 2000 to 2010 nationwide and locally.The result shows that,over the past decade,under the correct leadership of the CPC Central Committee and the State Council,China has succeeded in overcoming the impacts of many unfavorable factors including serious international financial crisis,rising production costs,the SARS epidemic,rare snow disasters and earthquakes, landslides,and the debt crisis of European sovereign. 展开更多
关键词 中国共产党 监测统计 小康社会 监测报告 工艺 科学研究所 国家统计局
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Vaccine pricing and production capacity in Africa: can Africa move beyond pooled procurement in the face of a future pandemic?
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作者 Christian Kwaku Osei Edward Nketiah-Amponsah +1 位作者 Ama Pokuaa Fenny Frank Otchere 《Global Health Journal》 2024年第4期172-180,共9页
We examine Africa's vaccine manufacturing potential,spurred by the coronavirus disease 2019(COVID-19)pan-demic,while critically analyzing vaccine price inequities and procurement strategies during the pandemic,wit... We examine Africa's vaccine manufacturing potential,spurred by the coronavirus disease 2019(COVID-19)pan-demic,while critically analyzing vaccine price inequities and procurement strategies during the pandemic,with anticipation of future outbreaks.Although Africa consumes approximately 25%of the global vaccine supply,over 99%of these vaccines are produced outside the continent,primarily due to insufficient local investment.Vaccine procurement strategies have relied heavily on pooled procurement mechanisms and tiered-pricing mod-els,predominantly controlled by external organizations.Significant disparities in vaccine pricing have resulted in vaccine price inequities,with evidence suggesting price discrimination,where different prices are charged for the same vaccine across countries and regions.While vaccine prices are only one component of vaccination cam-paign costs,the inequitable pricing of vaccines poses serious challenges to fair access,especially in low-income countries.Given the inevitability of future pandemics and other outbreaks,the central question remains:Does Africa possess the capacity to strengthen its vaccine production infrastructure and reduce dependency on ex-ternal suppliers?Our review reveals that,with robust political commitment,enhanced investment in Research and Development,and leveraging the heterogeneous nature of the regional bloc,Africa has made strides toward establishing vaccine manufacturing hubs with the potential for substantial capacity expansion.Furthermore,we argue for a regional campaign based on the principles of the fair priority model as an ethical framework for vaccine procurement,which prioritizes need and ensures equitable distribution,thereby complementing existing pooled procurement arrangements in times of future pandemics.This paper concludes with two key recommen-dations based on lessons learned from the COvID-19 crisis and future preparedness.First,Africa must push for a transparent and equitable tiered-pricing structure to ensure affordability for all Second,intentional and sustained investment in R&D is critical to addressing systemic inequities in vaccine supply,not only for cOVID-19 but for future outbreaks and routine immunization programs. 展开更多
关键词 Coronavirus disease 2019(COVID-19) Vaccine production Price inequity Pooled procurement ETHICS AFRICA
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B-type natriuretic peptide efficacy compared to fragmented QRS for diastolic dysfunction screening in patients with type 2 diabetes
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作者 Kunimasa Yagi Daisuke Chujo +8 位作者 Isao Usui Jian-Hui Liu Atsushi Nohara Asako Enkaku Shirozu Akiko Takikawa Hisae Honoki Shiho Fujisaka Hideki Origasa Hayato Tada 《World Journal of Diabetes》 2025年第4期84-95,共12页
BACKGROUND Early diagnosis of left ventricular diastolic dysfunction(LVDD)is essential for preventing heart failure.B-type natriuretic peptide(BNP)is a viable marker for predicting LVDD,as elevated BNP levels have bee... BACKGROUND Early diagnosis of left ventricular diastolic dysfunction(LVDD)is essential for preventing heart failure.B-type natriuretic peptide(BNP)is a viable marker for predicting LVDD,as elevated BNP levels have been associated with worsening LVDD in patients with diabetes over time.However,the utility of BNP as a diagnostic marker in diabetes is controversial,as BNP levels are often low in overweight individuals.AIM To examine the effectiveness of BNP levels and fragmented QRS(fQRS)on electrocardiography for diagnosing LVDD in patients with type 2 diabetes.METHODS This retrospective cohort study included 303 patients with type 2 diabetes(67.4±12.3 years old)with preserved ejection fraction(EF)≥50%admitted to Toyama University Hospital for glycemic management and comorbidity evaluation between November 2017 and April 2021.All participants underwent plasma BNP measurement,electrocardiography,and echocardiography.Cardiologists who were blinded to the BNP results assessed the electrocardiograms and echocardiograms.Subgroup analyses were conducted for overweight individuals.RESULTS Receiver operating characteristic(ROC)curve analysis determined optimal BNP cut-off values of 34.8 pg/mL and 7.2 pg/mL for diagnosing LVDD in non-overweight[area under the ROC curve(AUC):0.70]and overweight(AUC:0.55)groups,respectively(P=0.040).In the overweight subgroup,fQRS showed greater diagnostic accuracy for LVDD(AUC:0.67),indicating moderate diagnostic utility compared with the low performance of the BNP cutoff of 35 pg/mL(AUC:0.52)(P=0.010).Multivariate analyses confirmed that fQRS was superior to BNP for LVDD diagnosis regardless of the patient’s weight.CONCLUSION A BNP level≥35 pg/mL in non-overweight individuals may be a reliable LVDD marker.Additionally,fQRS was more effective than BNP in diagnosing LVDD irrespective of the patient’s weight.fQRS can complement BNP in the early detection of LVDD,especially in overweight patients,potentially improving early detection and mitigating progression to heart failure with preserved EF in patients with type 2 diabetes. 展开更多
关键词 B-type natriuretic peptide Diastolic dysfunction Fragmented QRS Heart failure with preserved ejection fraction OVERWEIGHT Type 2 diabetes
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Genetic analysis for brix weight per stool and its component traits in sugarcane (Saccharum officinarum) 被引量:1
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作者 LIU Gui-fu ZHOU Hong-kai +4 位作者 HU Han ZHU Zi-hong HAYAT Yousaf XU Hai-ming YANG Jian 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第12期860-866,共7页
Brix weight per stool (BW) of sugarcane is a complex trait, which is the final product of a combination of many components. Diallel cross experiments were conducted during a period of two years for BW and its five com... Brix weight per stool (BW) of sugarcane is a complex trait, which is the final product of a combination of many components. Diallel cross experiments were conducted during a period of two years for BW and its five component traits, in- cluding stalk diameter (SD), stalk length (SL), stalk number (SN), stalk weight (SW), and brix scale (BS) of sugarcane. Phenotypic data of all the six traits were analyzed by mixed linear model and their phenotype variances were portioned into additive (A), dominance (D), additive×environment interaction (AE) and dominance×environment interaction (DE) effects, and the correlations of A, D, AE and DE effects between BW and its components were estimated. Conditional analysis was employed to investigate the contribution of the components traits to the variances of A, D, AE and DE effects of BW. It was observed that the heritabilities of BW were significantly attributed to A, D and DE by 23.9%, 30.9% and 28.5%, respectively. The variance of A effect for BW was significantly affected by SL, SN and BS by 25.3%, 93.7% and 17.4%, respectively. The variances of D and DE effects for BW were also significantly influenced by all the five components by 5.1%~85.5%. These determinants might be helpful in sugarcane breeding and provide valuable information for multiple-trait improvement of BW. 展开更多
关键词 Genetic analysis Brix weight (BW) Component traits Sugarcane (Saccharum officinarum)
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Prediction of Anoxic Sulfide Biooxidation Under Various HRTs Using Artificial Neural Networks 被引量:1
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作者 QAISAR MAHMOOD PING ZHENG +6 位作者 DONG-LEI WU XU-SHENG WANG HAYAT YOUSAF EJAZ UL-ISLAM MUHAMMAD JAFFAR HASSAN GHULAM JILANI MUHAMMAD RASHID AZIM 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第5期398-403,共6页
Objective During present investigation the data of a laboratory-scale anoxic sulfide oxidizing (ASO) reactor were used in a neural network system to predict its performance. Methods Five uncorrelated components of t... Objective During present investigation the data of a laboratory-scale anoxic sulfide oxidizing (ASO) reactor were used in a neural network system to predict its performance. Methods Five uncorrelated components of the influent wastewater were used as the artificial neural network model input to predict the output of the effluent using back-propagation and general regression algorithms. The best prediction performance is achieved when the data are preprocessed using principal components analysis (PCA) before they are fed to a back propagated neural network. Results Within the range of experimental conditions tested, it was concluded that the ANN model gave predictable results for nitrite removal from wastewater through ASO process. The model did not predict the formation of sulfate to an acceptable manner. Conclusion Apart from experimentation, ANN model can help to simulate the results of such experiments in finding the best optimal choice for ASO based denitrification. Together with wastewater collection and the use of improved treatment systems and new technologies, better control of wastewater treatment plant (WTP) can lead to more effective maneuvers by its operators and, as a consequence, better effluent quality. 展开更多
关键词 Artificial neural networks Effluent sulfide prediction Effluent nitrite prediction Principal components analysis Wastewater treatment ASO reactor
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Inferring seismic hazard in Sichuan-Yunnan region of China based on the modern earthquake catalogue (1980-2019) 被引量:1
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作者 Ziyao Xiong Shiyong Zhou Jiancang Zhuang 《Earthquake Science》 2020年第3期107-115,共9页
Based on the modern earthquake catalogue,the incomplete centroidal voronoi tessellation(ICVT)method was used in this study to estimate the seismic hazard in Sichuan-Yunnan region of China.We calculated spatial distrib... Based on the modern earthquake catalogue,the incomplete centroidal voronoi tessellation(ICVT)method was used in this study to estimate the seismic hazard in Sichuan-Yunnan region of China.We calculated spatial distributions of the total seismic hazard and background seismic hazard in this area.The Bayesian delaunay tessellation smoothing method put forward by Ogata was used to calculate the spatial distributions of b-value.The results show that seismic hazards in Sichuan-Yunan region are high,and areas with relatively high hazard values are distributed along the main faults,while seismic hazards in Sichuan basin are relatively low. 展开更多
关键词 seismic hazard analysis Voronoi tessellation spatial smoothing B-VALUE
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Data replenishment of five moderate earthquake sequences in Japan, with semi-automatic cluster selection 被引量:1
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作者 Yi Zheng Bogdan Enescu +1 位作者 Jiancang Zhuang Coleman Yu 《Earthquake Science》 2021年第4期310-322,共13页
Missing early aftershocks following relatively large or moderate earthquakes can cause significant bias in the analysis of seismic catalogs.In this paper,we systematically address the aftershock missing problem for fi... Missing early aftershocks following relatively large or moderate earthquakes can cause significant bias in the analysis of seismic catalogs.In this paper,we systematically address the aftershock missing problem for five earthquake sequences associated with moderate-size events that occurred inland Japan,by using a stochastic replenishing method.The method is based on the notion that if a point process(e.g.,earthquake sequence)with timeindependent marks(e.g.,magnitudes)is completely observed,it can be transformed into a homogeneous Poisson process by a bi-scale empirical transformation.We use the Japan Meteorological Agency(JMA)earthquake catalog to select the aftershock data and replenish the missing early events using the later complete part of each aftershock sequence.The time windows for each sequence span from 6 months before the mainshock to three months after.The semi-automatic spatial selection uses a clustering method for the epicentral selection of earthquakes.The results obtained for the original JMA catalog and replenished datasets are compared to get insight into the biases that the missing early aftershocks may cause on the Omori-Utsu law parameters’estimation,characterizing the aftershock decay with time from the mainshock.We have also compared the Omori-Utsu law parameter estimates for two datasets following the same mainshock;the first dataset is the replenished sequence,while the second dataset has been obtained by waveform-based analysis to detect early aftershocks that are not recorded in the JMA catalog.Our results demonstrate that the Omori-Utsu law parameters estimated for the replenished datasets are robust with respect to the threshold magnitude used for the analyzed datasets.Even when using aftershock time windows as short as three days,the replenished datasets provide stable Omori-Utsu law parameter estimations.The p-values for all the analyzed sequences are about 1.1 and c-values are significantly smaller compared to those of original datasets.Our findings prove that the replenishment method is a fast,reliable approach to address the missing aftershock problem. 展开更多
关键词 Omori-Utsu law SEISMICITY clustering replenishment method Matched-Filter Technique(MFT).
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Levels, trends and determinants of fecundability in Bangladesh: A comparative study using Bangladesh health and demographic survey (BDHS) data 被引量:1
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作者 Farhana Hoque M. Sekander Hayat Khan Aminul Haque 《Open Journal of Preventive Medicine》 2012年第3期379-389,共11页
The concept of fecundability derives its importance for the study of human fertility from the fact that it is one of the principal determinants of fertility and is a major standard by which the impact of fertility reg... The concept of fecundability derives its importance for the study of human fertility from the fact that it is one of the principal determinants of fertility and is a major standard by which the impact of fertility regulation can be assessed;very few attempts have been made in Bangladesh for estimating fecundability. This study attempts to evaluate the levels, patterns, and trends of fecundability and identify the factors affecting fecundability in Bangladesh based on national surveys of Bangladesh Demographic and Health Survey (BDHS) 2007-1994. Total 9703 ever married women are included in the bivariate and multivariate analyses which reveal that age at first birth, age at marriage and marital duration play an important role in influencing marriage to first birth interval positively and thus fecundability negatively. Although fecundability in Bangladesh showed an increasing trend, but it is very low compared to developed and developing countries. 展开更多
关键词 BANGLADESH Fecundability MARRIAGE to First BIRTH INTERVAL FERTILITY and Logistic Regression
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Discrete Circular Distributions with Applications to Shared Orthologs of Paired Circular Genomes
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作者 Tomoaki Imoto Grace S.Shieh Kunio Shimizu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第6期1131-1149,共19页
For structural comparisons of paired prokaryotic genomes,an important topic in synthetic and evolutionary biology,the locations of shared orthologous genes(henceforth orthologs)are observed as binned data.This and oth... For structural comparisons of paired prokaryotic genomes,an important topic in synthetic and evolutionary biology,the locations of shared orthologous genes(henceforth orthologs)are observed as binned data.This and other data,e.g.,wind directions recorded at monitoring sites and intensive care unit arrival times on the 24-hour clock,are counted in binned circular arcs,thus modeling them by discrete circular distributions(DCDs)is required.We propose a novel method to construct a DCD from a base continuous circular distribution(CCD).The probability mass function is defined to take the normalized values of the probability density function at some pre-fixed equidistant points on the circle.Five families of constructed DCDs which have normalizing constants in closed form are presented.Simulation studies show that DCDs outperform the corresponding CCDs in modeling grouped(discrete)circular data,and minimum chi-square estimation outperforms maximum likelihood estimation for parameters.We apply the constructed DCDs,invariant wrapped Poisson and wrapped discrete skew Laplace to compare the structures of paired bacterial genomes.Specifically,discrete four-parameter wrapped Cauchy(nonnegative trigonometric sums)distribution models multi-modal shared orthologs in Clostridium(Sulfolobus)better than the others considered,in terms of AIC and Freedman’s goodness-of-fit test.The result that different DCDs fit the shared orthologs is consistent with the fact they belong to two kingdoms.Nevertheless,these prokaryotes have a common favored site around 70°on the unit circle;this finding is important for building synthetic prokaryotic genomes in synthetic biology.These DCDs can also be applied to other binned circular data. 展开更多
关键词 Bacterial genomes circular distribution goodness-of-fit test modeling synthetic and evolutionary biology.
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Balancing timber production and habitat conservation of Okinawa Rails(Gallirallus okinawae): Application of a harvest scheduling optimization model in subtropical forest in Okinawa, Japan
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作者 KONOSHIMA Masashi YOSHIMOTO Atsushi 《Journal of Mountain Science》 SCIE CSCD 2019年第12期2770-2782,共13页
Finding the right balance between timber production and the management of forest-dependent wildlife species,present a difficult challenge for forest resource managers and policy makers in Okinawa,Japan.A possible expl... Finding the right balance between timber production and the management of forest-dependent wildlife species,present a difficult challenge for forest resource managers and policy makers in Okinawa,Japan.A possible explanation of this can be found in the unique nature of the forest management area which is populated with various kinds of rare and endangered species.This issue has been brought to light as a result of the nomination of northern Okinawa Island in 2018 as a candidate for World Natural Heritage site.The nomination has raised public awareness to the possibility of conflicting management objectives between timber extraction and the conservation of habitat for forest-dependent wildlife species.Managing exclusively for one objective over the other may fail to meet the demand for both forest products and wildlife habitat,ultimately jeopardizing the stability of human and wildlife communities.It is therefore important to achieve a better balance between the objective of timber production and conservation of wildlife habitat.Despite the significance of this subject area,current ongoing discussions on how to effectively manage for forest resources,often lack scientific basis to make sound judgement or evaluate tradeoffs between conflicting objectives.Quantifying the effect of these forest management activities on wildlife habitat provides useful and important information needed to make forest management and policy decisions.In this study we develop a spatial timber harvest scheduling model that incorporates habitat suitability index(HSI)models for the Okinawa Rail(Gallirallus okinawae),an endangered avian species found on Okinawa,Japan.To illustrate how the proposed coupling model assembles spatial information,which ultimately aids the study of forest management effects on wildlife habitat,we apply these models to a forest area in Okinawa and conduct a simple simulation analysis. 展开更多
关键词 Harvest scheduling Habitat suitability index model Optimization model Timber production Wildlife habitat
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Modeling the Browsing Behavior of World Wide Web Users
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作者 Frederick Kin Hing Phoa Juana Sanchez 《Open Journal of Statistics》 2013年第2期145-154,共10页
The World Wide Web is essential to general public nowadays. From a data analysis viewpoint, it provides rich opportunities to gather observational data on a large-scale. This paper focuses on modeling the behavior of ... The World Wide Web is essential to general public nowadays. From a data analysis viewpoint, it provides rich opportunities to gather observational data on a large-scale. This paper focuses on modeling the behavior of visitors to an academic website. Although the conventional probability models, which were used by other literature for fitting in a commercial web site, capture the power law behavior in our data, they fail to capture other important features like the long tail. We propose a new model based on the identities of the users. Qualitative and quantitative tests, which are used for comparing the model fitting to our data, show that the new model outperforms other two conventional probability models. 展开更多
关键词 Power Law Long TAIL Negative BINOMIAL DISTRIBUTION Inverse Gaussian DISTRIBUTION PARETO DISTRIBUTION KOLMOGOROV-SMIRNOV Test
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Seroconversion of Hepatitis B Vaccine in Young Bangladeshi Children: A Tertiary Centre Experience
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作者 Salahuddin Mahmud Jahida Gulshan +1 位作者 Farhana Tasneem Syed Shafi Ahmed 《World Journal of Vaccines》 2021年第2期7-18,共12页
<strong>Background:</strong> Hepatitis B virus (HBV) infection is one of the most important global health problems and active immunization is the single most important and effective preventive measure agai... <strong>Background:</strong> Hepatitis B virus (HBV) infection is one of the most important global health problems and active immunization is the single most important and effective preventive measure against HBV infection. Several studied show that HBV carrier rate is between 2% - 7% in Bangladesh. Bangladesh introduced hepatitis B vaccination in children through Expanded Program on Immunization (EPI) in 2005 that includes 3 doses which starts from six weeks after birth. Currently booster vaccination is not recommended any more. However, many studies on different countries observed a declined level of HBs-antibody over a period of 3 - 6 years that may even reach to non-protective levels. <strong>Objective:</strong> To evaluate the status of seroconversion and seroprotection along with non-responders of EPI vaccinated children against HBV and to measure their antibody levels in different age groups. <strong>Methods:</strong> A cross sectional descriptive study was done in the department of Pediatric Gastroenterology, Hepatology & Nutrition, Dhaka Shishu (Children) Hospital, Dhaka, Bangladesh on 120 cases of EPI vaccinated children enrolled from January-December 2019 while attending the inpatient department without any liver problem. The development of Anti-HBs titre greater than or equal to 10 mIU/mL is considered as protective immunity and any titre less than 10 mIU/mL as non-protective following HBV vaccination. <strong>Results:</strong> Age of the children was 1 - 12 years with mean age of 5.6 ± 1.7 years and male: female ratio was 1.1:1. Among the children, 56 (46.6%) were from 1 - 5 years age, 36 (30.1%) children from 6 - 10 years age group and 27 (23.3%) children from 11 - 12 years age group. Out of 120 children, presence of Anti-HBs protective titre was in 63 (52.5%) children and non-protective level in 57 (47.5%) children. Among protective level, 34 (60.7%) children were in 1 - 5 years age group, 18 (50.0%) children in 6 - 10 years age group and 11 (39.3%) children in 11 - 12 years age group. Total 24 (20%) children were completely non-responder (antibody titre 0.00 mIU/mL). Out of 120 mother, 06 (5%) were HBV positive. Among them 05 (83.33%) children had Anti-HBs less than 10 mIU/mL. <strong>Conclusion:</strong> After primary vaccination, a good immune response was detected against hepatitis B virus but it goes below even up to non-protective level with the increase of age. Half of the studied children had non-protective titre after 5 years and one-fifth children totally non-responder after primary hepatitis B vaccination. A booster dose may be recommended after 5 years for optimum seroprotection. 展开更多
关键词 Hepatitis B Virus Expanded Program on Immunization Immune Response Antibody Titre
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Do Farmers Respond to Training?--The Case of the Millennium Challenge Account (MCA)-Ghana Programme
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作者 Robert Darko Osei Isaac Osei Akoto +1 位作者 Andrew Agyei-Holmes Hayford Mensah Ayerakwa 《Journal of Food Science and Engineering》 2013年第11期592-608,共17页
This study examined the effect of farmer business, technical training and input provision through a government intervention programme on productivity and crop incomes among Farmer Based Organizations (FBO) in Ghana.... This study examined the effect of farmer business, technical training and input provision through a government intervention programme on productivity and crop incomes among Farmer Based Organizations (FBO) in Ghana. Farm level data were collected from 2,900 farmers over 11,000 farm plots. The difference-in-difference estimator is employed to test the impact of this intervention on crop yields and incomes. Farmers were randomly put into two distinct groups: the treatment (early training) and control (late training). After the collection of baseline data, the treatment group received crop husbandry training and a starter pack which included inputs and cash both worth about US$230. The control group received the intervention after a year. The main findings of this study are that the intervention does not have any significant impact on crop yields and crop incomes. However the authors do find some evidences that as a result of the intervention, the value of chemicals used by farmers decreased by about GH^25 The study concludes by noting that although some changes do occur over the period, and it is not possible to attribute these changes to the MiDA training programme for all the indicators of interest except chemical costs. 展开更多
关键词 Agriculture productivity farmer incomes training.
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Tour Planning for Sightseeing with Time-Dependent Satisfactions of Activities and Traveling Times
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作者 Takashi Hasuike Hideki Katagiri +1 位作者 Hiroe Tsubaki Hiroshi Tsuda 《American Journal of Operations Research》 2013年第3期369-379,共11页
This paper proposes a new personal tour planning problem with time-dependent satisfactions, traveling and activity duration times for sightseeing. It is difficult to represent the time-dependent model using general st... This paper proposes a new personal tour planning problem with time-dependent satisfactions, traveling and activity duration times for sightseeing. It is difficult to represent the time-dependent model using general static network models, and hence, Time-Expanded Network (TEN) is introduced. The TEN contains a copy to the set of nodes in the underlying static network for each discrete time step, and it turns the problem of determining an optimal flow over time into a classical static network flow problem. Using the proposed TEN-based model, it is possible not only to construct various variations with time of costs and satisfactions flexibly in a single network, but also to select optimal departure places and accommodations according to the tour route with tourist’s favorite places and to obtain the time scheduling of tour route, simultaneously. The proposed model is formulated as a 0 - 1 integer programming problem which can be applied by existing useful combinatorial optimization and soft computing algorithms. It’s also equivalently transformed into several existing tour planning problems using some natural assumptions. Furthermore, comparing the proposed model with some previous models using a numerical example with time-dependent parameters, both the similarity of these models in the static network and the advantage of the proposed TEN-based model are obtained. 展开更多
关键词 TOUR PLANNING Problem TIME-DEPENDENT Parameters Time-Expanded Network Mathematical Modeling
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RCEP UNDER PROFOUND CHANGES UNSEEN IN A CENTURY:FEATURES,IMPACTS AND OPPORTUNITIES
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作者 SHEN MINGHUI GUO MINYING 《Contemporary World》 2021年第2期34-38,共5页
The world today is undergoing profound changes unseen in a century,that are accelerated by the global spread of Covid-19 pandemic.On November 15,2020,15 member parties including China signed the Regional Comprehensive... The world today is undergoing profound changes unseen in a century,that are accelerated by the global spread of Covid-19 pandemic.On November 15,2020,15 member parties including China signed the Regional Comprehensive Economic Partnership(RCEP).On March 8,2021,the Chinese Government declared official rectification of the RCEP.In the future,as other signatories rectify the agreement(when six member states of the ASEAN and three non-ASEAN countries do so),this Free Trade Area(FTA)will become operational,one that boasts the world’s largest population,largest economic and trade size,and greatest development potentials.Not only is the RCEP the most important milestone in the Asia-Pacific regional economic cooperation,it has also injected strong driving force to the ebbing economic globalization and the international economic and trade cooperation. 展开更多
关键词 driving ASEAN ECONOMIC
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Regulatory intervention rescued China from the impact of the global financial crisis
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作者 李平 余根钱 《China Economist》 2010年第2期40-49,共10页
Following the order of events, this paper makes a systematic and comprehensive summary of how the global financial crisis of 2008 affected China. It includes an econometric assessment using by-industry and by-region d... Following the order of events, this paper makes a systematic and comprehensive summary of how the global financial crisis of 2008 affected China. It includes an econometric assessment using by-industry and by-region data, and describes the role of government regulation from a new perspective. China's economic recovery is a result of regulatory intervention, and enhancing economic momentum created conditions for such intervention to phase out. 展开更多
关键词 global FINANCIAL CRISIS RECESSION GOVERNMENT regulation economic recovery
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Conditional logistic individual-level models of spatial infectious disease dynamics
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作者 Tahmina Akter Rob Deardon 《Infectious Disease Modelling》 2025年第1期268-286,共19页
Here,we introduce a novel framework for modelling the spatiotemporal dynamics of disease spread known as conditional logistic individual-level models(CL-ILM's).This framework alleviates much of the computational b... Here,we introduce a novel framework for modelling the spatiotemporal dynamics of disease spread known as conditional logistic individual-level models(CL-ILM's).This framework alleviates much of the computational burden associated with traditional spatiotemporal individual-level models for epidemics,and facilitates the use of standard software for fitting logistic models when analysing spatiotemporal disease patterns.The models can be fitted in either a frequentist or Bayesian framework.Here,we apply the new spatial CL-ILM to simulated data,semi-real data from the UK 2001 foot-and-mouth disease epidemic,and real data from a greenhouse experiment on the spread of tomato spotted wilt virus. 展开更多
关键词 Disease transmission model ILMs Logistic ILM Conditional logistic ILM Posterior predictive distribution
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Perceptual Contrast-Based Image Fusion: A Variational Approach 被引量:6
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作者 WANG Chao YE Zhong-Fu 《自动化学报》 EI CSCD 北大核心 2007年第2期132-137,共6页
本地对比,或变化,在主要是从来源图象保存重要信息到熔化结果的图象熔化起一个重要作用。威伯的法律告诉我们在不同背景下面的一样的变化将引起不同感性的感情,因此,一个理想的图象处理器不得不考虑视觉心理学和心物学的效果。这份... 本地对比,或变化,在主要是从来源图象保存重要信息到熔化结果的图象熔化起一个重要作用。威伯的法律告诉我们在不同背景下面的一样的变化将引起不同感性的感情,因此,一个理想的图象处理器不得不考虑视觉心理学和心物学的效果。这份报纸考虑人的视觉系统(HVS ) 的性质并且从每幅来源图象把量的感性的变化转移到结果。把 just-noticeable-difference (JND ) 用作测量, multiband 图象的感性的对比作为一个目标被获得。我们构造一个功能的极值问题发现一幅单身的乐队图象,或熔化结果,它有最近感性的对比到目标一个。经由变化途径, Euler-Lagrange 方程被导出,并且一次坡度降下重复被采用。试验性的结果证明这个方法感性地好。 展开更多
关键词 表象聚变 变化方法 知觉衬比度 HVS PDES 人工智能
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A test on methods for MC estimation based on earthquake catalog 被引量:11
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作者 YiJian Zhou ShiYong Zhou JianCang Zhuang 《Earth and Planetary Physics》 2018年第2期150-162,共13页
This study tested five methods widely used in estimating the complete magnitudes(M_C) of earthquake catalogs. Using catalogs of observed earthquake properties, we test the performance of these five algorithms under se... This study tested five methods widely used in estimating the complete magnitudes(M_C) of earthquake catalogs. Using catalogs of observed earthquake properties, we test the performance of these five algorithms under several challenging conditions, such as small volume of events and spatial-temporal heterogeneity, in order to see whether the algorithms are stable and in agreement with known data. We find that the maximum curvature method(MAXC) has perfect stability, but will significantly underestimate M_C unless heterogeneity is absent. M_C estimated by the b-value stability method(MBS) requires many events to reach a stable result. Results from the goodness of fit method(GFT) were unstable when heterogeneity lowered the fitness level. The entire magnitude range method(EMR) is relatively stable in most conditions, and can reflect the change in M_C when heterogeneity exists, but when the incomplete part of the earthquake catalog is dismissed, this method fails. The median-based analysis of the segment slope method(MBASS) can tolerate small sample size, but is incapable of reflecting the missing degree of small events in aftershock sequences. In conditions where M_C changes rapidly, such as in aftershock sequences, observing the time sequence directly can give a precise estimation of the complete sub-catalog, but only when the number of events available for study is large enough can the MAXC, GFT, and MBS methods give a similarly reliable estimation. 展开更多
关键词 COMPLETE MAGNITUDE of an EARTHQUAKE CATALOG G-R law B-VALUE FMD
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