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Study of the Effect of Climate Variability on Hydroelectric Power Generation Capacity:The Case of the Garafiri Dam in Guinea
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作者 Souleymane Soumah Mohamed Ansoumane Camara +4 位作者 Bangaly Kourouma Moussa Mamady Traore Amadou Lamarana Bah Mouhamadou Falilou Ndiaye Vincent Sambou 《Journal of Energy and Power Engineering》 2025年第1期36-43,共8页
Hydroelectric power production from Garafiri dam and rainfall are essential elements with the observation of hydroelectric power production in West African power system,particularly in Guinea.This article focuses on t... Hydroelectric power production from Garafiri dam and rainfall are essential elements with the observation of hydroelectric power production in West African power system,particularly in Guinea.This article focuses on the study and the influence of climate variability on hydroelectric power production at Garafiri dam over 16-year period(2008-2023).The aim of this work is to show the correlation between rainfall anomalies and hydroelectric power production at Garafiri dam.The method used consists of calculating precipitation anomalies at Garafiri site and those for the production of hydroelectric power from Garafiri dam over the study period.This approach led us to calculate the anomalies,leading to the study on climatic variability,in order to establish correlation between rainfall and hydroelectric power dam’s production.The trend with the correlation found made it possible to carry out a significance test between these two variables.These results clearly show that rainfall in Garafiri site increases hydroelectric power production and vice versa,which explains the interdependence between these two parameters,i.e.climatic variability and hydroelectric power production. 展开更多
关键词 DAM Garafiri energy production RAINFALL HYDROELECTRICITY
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Resilience against exercise-related coronary atherosclerosis:A case study in a master athlete participating in 500 marathons
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作者 Beat Knechtle Sasa Duric +8 位作者 Volker Scheer Pantelis T.Nikolaidis Daniela Chlíbková Luciano Bernardes Leite Ivan Cuk Pedro Forte Matthias Wilhelm Katja Weiss Thomas Rosemann 《Sports Medicine and Health Science》 2026年第2期219-227,共9页
Background and purpose: Lifelong endurance exercise is generally associated with cardiovascular health benefits.However, recent studies suggest that prolonged high-volume training may contribute to coronary atheroscle... Background and purpose: Lifelong endurance exercise is generally associated with cardiovascular health benefits.However, recent studies suggest that prolonged high-volume training may contribute to coronary atherosclerosis,even in athletes with low traditional cardiovascular risk. This case report aims to explore the cardiovascular status of a master endurance athlete with an exceptionally high lifetime training volume, in light of recent concerns raised in the literature.Methods: We present the case of a 60-year-old recreational male marathon runner with no history of cardiovascular disease, who completed over 500 marathons between the ages of 30 and 60 years, covering ~127 000-km running. In 2024 alone, he completed 60 marathons. Cardiovascular evaluation included clinical risk assessment and coronary computed tomography angiography(CTCA).Results: The runner was asymptomatic, had a low ESC-SCORE2(3.3%), a favorable lipid profile, and normal levels of high-sensitivity C-reactive protein and lipoprotein(a). CTCA revealed no evidence of calcified, mixed, or non-calcified coronary plaques.Conclusions: This case highlights that some master athletes may demonstrate resilience to coronary atherosclerosis despite decades of high training volume. In low-risk individuals, prolonged endurance training alone may not necessarily lead to coronary artery disease, emphasizing the need for individualized cardiovascular screening strategies. 展开更多
关键词 Running Middle-aged man Cardiovascular disease
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Localized Excitations of (2+1)-Dimensional Korteweg-de Vries System Derived from a Periodic Wave Solution
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作者 QIANG Ji-Ye FEI Jin-Xi +1 位作者 CAI Gui-Ping ZHENG Chun-Long 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期275-281,共7页
With the aid of an improved projective approach and a linear variable separation method, new types of variable separation solutions (including solitary wave solutions, periodic wave solutions, and rational function s... With the aid of an improved projective approach and a linear variable separation method, new types of variable separation solutions (including solitary wave solutions, periodic wave solutions, and rational function solutions) with arbitrary functions for (2+1)-dimensional Korteweg-de Vries system are derived. Usually, in terms of solitary wave solutions and rational function solutions, one can find some important localized excitations. However, based on the derived periodic wave solution in this paper, we find that some novel and significant localized coherent excitations such as dromions, peakons, stochastic fractal patterns, regular fractal patterns, chaotic line soliton patterns as well as chaotic patterns exist in the KdV system as considering appropriate boundary conditions and/or initial qualifications. 展开更多
关键词 improved projective approach KdV system chaos SOLITON FRACTAL
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The Evaluation of Social Sharing Nets Users’ Fundamental Principals According to Nickname Usage and Time Spent
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作者 Mehmet Ali Seven Mustafa Çağrı Engin +1 位作者 Mehmet Yıldız Ali Osman Engin 《Advances in Internet of Things》 2023年第2期31-62,共32页
This work;It was made to determine the positive and negative usage information, attitudes and behaviors of social networking networks for users. Today, it is well known how the wide social effects of social networking... This work;It was made to determine the positive and negative usage information, attitudes and behaviors of social networking networks for users. Today, it is well known how the wide social effects of social networking sites are widespread and effective. As far as it can be followed from written and visual media, it causes significant damages for attitudes and behaviors for individuals. Looking at the results of the study, it seems impossible to limit the time and necessity of these networks for people, but it is understood that people force their limits and capacity. It was determined that the general acceptance and rejection areas are mixed and the dominant distinctive effects were weakened. Unable to prevent social dissolution and deterioration was realized by these social networks of networks. However, we cannot only talk about negative effects because their positive effects should be mentioned. Data were obtained in this direction. For example, some segments encourage the users of these sites to have more freedom, to develop democracy and human rights awareness. However, the real problem is when and where to stand. This study;Social networking networks use information, attitudes and behaviors;It was carried out for the purpose of evaluating the use of nicknames and networks for the use of networks. The data of the study were obtained by the application of a questionnaire and the data obtained were analyzed with appropriate statistical analysis methods. In the first part of the study, field study/operational concept scanning is performed and theoretical information is included. In the second part, the purpose of the study, the problem status, the importance of the study, limitations, assumptions, problem question, research method, research universe and sample are specified and informed. In the third section, the data obtained using appropriate statistical methods are analyzed. In the last section, some important suggestions and comments are made in the light of the data obtained. 展开更多
关键词 Psycho-Social Effect of Facebook Facebook and Personal Harms Habitual Activity of Using Facebook Nickname Usage and Social Sharing Nets
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Update on Canine and Human Rabies in a Rabies Endemic Situation in the Republic of Guinea
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作者 Alimou Camara Mamady Cissé +8 位作者 Timothé Guilavogui Charles Louanga Loua Amadou Sadio Bah Kouramodou Bérété Djibril Sylla Kaba Kourouma Mamady Biton Koulibaly Mamadou Saliou Sow Sanaba Boumbaly 《Journal of Immune Based Therapies, Vaccines and Antimicrobials》 2024年第4期55-66,共12页
Each year, rabies kills nearly 60,000 people worldwide. Asia and Africa are the most affected. It is a public health problem because of the number of stray dogs in these nations. In Guinea, rabies is endemic and cases... Each year, rabies kills nearly 60,000 people worldwide. Asia and Africa are the most affected. It is a public health problem because of the number of stray dogs in these nations. In Guinea, rabies is endemic and cases are often under-reported. The objective of this study was to determine the prevalence of rabies among human and animal exposures in Guinea. This was a retrospective analytical study from 2019 to 2021 conducted in the country’s human and veterinary health divisions and, primarily focused on rabies épidémiologique surveillance. The selection was based on human contact with an animal causing behavioural disorders, as well as animals put under observation following aggression on humans. The data were analysed using Epi Info version 21 software. Qualitative variables were expressed as proportions with 95% CIs, quantitative variables as mean ± standard deviation. The chi2 test and the Fischer exact test were used to compare proportions. A total of 85 veterinary facilities were visited and 100 animals registered, of which 93% were reported cases of exposure to canine rabies. One thousand five hundred and thirty-one (1531) people exposed to rabies were recorded between 2019 and 2021. During the period, the prevalence of human rabies was 0.533% [0.042 - 0.064] at 95% CI and that of canine rabies was 0.55% [0.039 - 0.061] at 95% CI. The biting animal was the dog in 97.2% of cases. Subjects over 45 years of age (57.7%) were the most affected. The prevalence of canine rabies was 0.5% compared with 0.533% for human rabies between 2019 and 2021. This low prevalence does not reflect the true extent of the phenomenon in Guinea, as few people consult health structures in the event of dog bites. Regular surveillance of the human and dog population is necessary for better rabies control in Guinea. 展开更多
关键词 SEROPREVALENCE Canine and Human Rabies Conakry GUINEA
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Construction and Optimization of the Curriculum System for Physics Major in Normal Universities from the Perspective of Knowledge Graphs
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作者 Yufei Wei Guoren Yang Xingcheng Qin 《Journal of Contemporary Educational Research》 2026年第3期57-65,共9页
Against the dual backdrop of the digital transformation of education and the quality and efficiency improvement of teacher education,the curriculum system for physics major in normal universities is confronted with pr... Against the dual backdrop of the digital transformation of education and the quality and efficiency improvement of teacher education,the curriculum system for physics major in normal universities is confronted with practical predicaments such as fragmented knowledge,weakened interdisciplinary connections,and disjointed competency cultivation.Based on constructivism theory,connectivism learning theory,and teacher professional development theory,this paper introduces knowledge graph technology and constructs a“three-dimensional integrated”optimization framework for the curriculum system.By sorting out the core competencies and graduation requirements of physics major in normal universities,extracting knowledge nodes,ability nodes,and competency nodes in the curriculum system,and using Neo4j and CiteSpace tools to draw disciplinary knowledge graphs,teaching ability graphs,and interdisciplinary integration graphs,a visualized curriculum correlation network is formed.Taking the 2022 and 2023 grade students of physics major at Chengdu Normal University as the empirical subjects,a comparative study shows that the optimization of the curriculum system from the perspective of knowledge graph can effectively solve the structural defects of traditional curricula,realize the coordinated development of“knowledge-ability-competency,”and provide a replicable and promotable practical paradigm for the reform of the curriculum system of science majors in normal universities. 展开更多
关键词 Knowledge graph Physics in normal universities Curriculum system Core competencies Teacher professional development
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尝试教学法在中国的诞生与发展 被引量:7
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作者 邱学华 《中国教育科学(中英文)》 2015年第3期3-19 2 243,共19页
尝试教学法诞生的过程,充分证明尝试教学法的本土性和原创性。针对20世纪60年代"先讲后练"教学模式的弊病,萌发"先练后讲"的教学设想,经过10年的教育实验和探索,终于形成了尝试教学法。这种教学法抓住了学习的本质... 尝试教学法诞生的过程,充分证明尝试教学法的本土性和原创性。针对20世纪60年代"先讲后练"教学模式的弊病,萌发"先练后讲"的教学设想,经过10年的教育实验和探索,终于形成了尝试教学法。这种教学法抓住了学习的本质,突出学生为主体,具有鲜明的中国特色,教师易学易用,教学效果显著,深受师生欢迎。再经过10多年的教育实验和研究,提升为具有中国特色的尝试教学理论,它的理论核心是"学生能尝试,尝试能成功,成功能创新"。创造性地提出"尝试成功说",区别于美国桑代克提出的"尝试错误说",并提出达到尝试成功的七个要素。又经过10年的实验研究提出尝试教育理论。 展开更多
关键词 先练后讲 尝试教学法 尝试教学理论 尝试教育理论
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Personal knowledge in educational autobiography:An investigation on“good teachers”
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作者 LIU Lianghua 《Frontiers of Education in China》 2009年第1期123-132,共10页
A good teacher has various characteristics.We can observe directly teachers'behaviors or read their professional papers.However,the effective way is to have teachers tell their personal life history or educational... A good teacher has various characteristics.We can observe directly teachers'behaviors or read their professional papers.However,the effective way is to have teachers tell their personal life history or educational autobiography.The personal knowledge of a good teacher will be revealed through the personal life history.According to numerous educational autobiographies,a good teacher has two characteristics:being kind to students and having passion. 展开更多
关键词 good teacher personal knowledge educational autobiography
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Psychology studies’drive to educational reform in the last 20 years in China
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作者 Zhang Da-jun Xu Xing-chun 《Frontiers of Education in China》 2006年第4期630-641,共12页
In order to better understand the relationship between educational psychology research and educational reform,this essay reviews the development of educational psychology studies in the last 20 years in China.The stud... In order to better understand the relationship between educational psychology research and educational reform,this essay reviews the development of educational psychology studies in the last 20 years in China.The study shows that:(1)Rapid development has been made in the areas of establishing discipline systems;(2)Research fields have been expanded and research directions have been localized;(3)The theoretical basis for quality education has been derived from education psychology studies;(4)The psychological foundation for curriculum reform and instruction has been implemented,and(5)China has committed to serve and expand current educational practices. 展开更多
关键词 educational psychology educational reform in China promotion effect
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Combined energy detection and one-order cyclostationary feature detection techniques in cognitive radio systems 被引量:2
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作者 YUE Wen-jing ZHENG Bao-yu +1 位作者 MENG Qing-min YUE Wen-jie 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2010年第4期18-25,共8页
One of the main requirements of cognitive radio systems is the ability to detect the presence of the primary user with fast speed and precise accuracy. To achieve that, a possible two-stage spectrum sensing scheme is ... One of the main requirements of cognitive radio systems is the ability to detect the presence of the primary user with fast speed and precise accuracy. To achieve that, a possible two-stage spectrum sensing scheme is suggested in this paper. More specifically, a fast spectrum sensing algorithm based on the energy detection is introduced focusing on the coarse detection. A complementary fine spectrum sensing algorithm adopts one-order cyclostationary properties of primary user's signals in time domain. Since the one-order feature detection is performed in time domain, the real-time operation and low-computational complexity can be achieved. Also, it drastically reduces hardware burdens and power consumption as opposed to two-order feature detection. The sensing performance of the proposed method is studied and the analytical performance results are given. The results indicate that better performance can be achieved in proposed two-stage sensing detection compared to the conventional energy detector. 展开更多
关键词 cognitive radio (CR) spectrum sensing energy detector cyclostationary feature detector
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