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Community Knowledge and Attitude about Burns First Aid (BFA) in Jazan, Saudi Arabia
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作者 Md. Mazharul Hoque Mohamed E. Moukhyer +9 位作者 Nizar A. Khamjan Bahja Al Siddig Elsie Maguen Shane Alam Abdulrahman Ibrahim Ali Hakami Siraj Yahya Mohammed Mobarki Bandar Hassan Sulaiman Ghazwani Ayman Abdulrhman Alhathiq Lamyaa El Hassan Aziza Mukhayer 《Journal of Biosciences and Medicines》 2024年第4期135-148,共14页
Introduction and Significance: Burn injury (BI) is a considerable health issue which is responsible for around 300,000 deaths and affecting about 11 million people every year worldwide. In Saudi Arabia, the prevalence... Introduction and Significance: Burn injury (BI) is a considerable health issue which is responsible for around 300,000 deaths and affecting about 11 million people every year worldwide. In Saudi Arabia, the prevalence of BIs array from 112 to 518 per 100,000 per year. The appropriate awareness of performing first aid could facilitate to improve the outcomes of burns. Purpose and Objectives: To appraise the community that acknowledges burns, first aid, and associated factors among the community population in Jazan City, Saudi Arabia. The paper aims to identify limitations to encourage additional research and persuade legislators to develop improved burn-injury care recommendations and training programs. Materials and Methods: An observational-based sample survey was conducted among the people who live in Jazan City aging 13 years or more, during April 5 to May 5, 2023. Data collection was done by a validated online self-administrated questionnaire sent randomly to community members in different parts of Jazan City via social media platforms. Collected data were coded and cleaned by an excel program, and finally exported on SPSS 26.0 software. The variables were analyzed using descriptive statistics like frequencies and percentages. Also, the Chi-square test was used to investigate the relation between different variables, with a significance value of P Results: This study included 243 participants (about 62%) among them were mostly male participants (151) having a university degree. The majority of participants 75% did not take any form of BFA training in the past. This study shows that 69.9% of the participants have inadequate awareness, despite 72% having a constructive attitude towards burn first aid. Previous burn-related first aid training was significantly associated with participants’ knowledge of BFA at a p-value less than 0.05. Conclusion: This study indicates a high frequency of Jazan population having inadequate knowledge of burn first aid despite the high prevalence of a favorable attitude. There is a need to develop an effective nationwide burn prevention program and early burn first aid treatment in Saudi Arabia and promote a consistent guideline for burn first aid. 展开更多
关键词 Burn Injury (BI) Burns first Aid Knowledge first Aid Training Jazan City
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FIRST简易版虚弱评估量表评分在新诊断多发性骨髓瘤患者中的应用价值分析
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作者 姚琼 王鑫炜 +4 位作者 杨慧 李林宇 赵洁 贺少龙 田卫伟 《中国临床新医学》 2024年第2期186-191,共6页
目的分析FIRST简易版虚弱评估量表评分在新诊断多发性骨髓瘤(NDMM)患者中的应用价值。方法回顾性分析2014年7月1日至2021年12月31日山西医科大学第三医院收治的131例NDMM患者的临床资料。根据FIRST简易版虚弱评估量表评分将其分为虚弱组... 目的分析FIRST简易版虚弱评估量表评分在新诊断多发性骨髓瘤(NDMM)患者中的应用价值。方法回顾性分析2014年7月1日至2021年12月31日山西医科大学第三医院收治的131例NDMM患者的临床资料。根据FIRST简易版虚弱评估量表评分将其分为虚弱组(50例)和非虚弱组(81例)。比较两组患者疗效、累积早期≥3级感染发生率及生存预后情况。并对接受硼替佐米为基础诱导治疗方案的患者进行亚组分析。结果两组疗效为≥非常好的部分缓解(VGPR)的人数比例差异无统计学意义(45.68%vs 36.00%,P>0.05)。虚弱组和非虚弱组分别有26例(52.00%)和27例(33.33%)发生早期≥3级感染,虚弱组早期≥3级感染相关预后更差(log-rank检验:χ^(2)=4.472,P=0.020)。虚弱组中位总生存(OS)时间和中位无进展生存(PFS)时间均短于非虚弱组(36个月vs 81个月;16个月vs 34个月),非虚弱组生存预后情况显著优于虚弱组(P<0.05)。在接受硼替佐米为基础诱导方案治疗的100例患者中,虚弱组中位OS时间和中位PFS时间均短于非虚弱组(34个月vs 84个月;15个月vs 33个月),非虚弱组生存预后情况显著优于虚弱组(P<0.05)。结论FIRST简易版虚弱评估量表评分对NDMM患者有较好的应用价值。 展开更多
关键词 多发性骨髓瘤 first简易版虚弱评估量表 虚弱 感染 预后
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Estimation of Landfill Gas and Its Renewable Energy Potential from the Polesgo Controlled Landfill Using First-Order Decay (FOD) Models
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作者 Haro Kayaba Ouarma Issoufou +4 位作者 Dabilgou Téré Compaore Abdoulaye Sanogo Oumar Bere Antoine Koulidiati Jean 《Journal of Environmental Protection》 2024年第10期975-993,共19页
Methane generation in landfills and its inadequate management represent the major avoidable source of anthropogenic methane today. This paper models methane production and the potential resources expected (electrical ... Methane generation in landfills and its inadequate management represent the major avoidable source of anthropogenic methane today. This paper models methane production and the potential resources expected (electrical energy production and potential carbon credits from avoided CH4 emissions) from its proper management in a municipal solid waste landfill located in Ouagadougou, Burkina Faso. The modeling was carried out using two first-order decay (FOD) models (LandGEM V3.02 and SWANA) using parameters evaluated on the basis of the characteristics of the waste admitted to the landfill and weather data for the site. At the same time, production data have been collected since 2016 in order to compare them with the model results. The results obtained from these models were compared to experimental one. For the simulation of methane production, the SWANA model showed better consistency with experimental data, with a coefficient of determination (R²) of 0.59 compared with the LandGEM model, which obtained a coefficient of 0.006. Thus, despite the low correlation values linked to the poor consistency of experimental data, the SWANA model models methane production much better than the LandGEM model. Thus, despite the low correlation values linked to the poor consistency of the experimental data, the SWANA model models methane production much better than the LandGEM V3.02 model. It was noted that the poor consistency of the experimental data justifies these low coefficients, and that they can be improved in the future thanks to ongoing in situ measurements. According to the SWANA model prediction, in 27 years of operation a biogas plant with 33% electrical efficiency using biogas from the Polesgo landfill would avoid 1,340 GgCO2e. Also, the evaluation of revenues due to electricity and carbon credit gave a total revenue derived from methane production of US$27.38 million at a cost of US$10.5/tonne CO2e. 展开更多
关键词 first-Order Decay METHANE Modeling LANDFILL Renewable Energy
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Community Knowledge about Bleeding Control in Jazan, KSA: Is There a Need for First Aid Educational Programs
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作者 Md Mazharul Hoque Hamoud Yahya Alsuriha +10 位作者 Mohamed E. Moukhyer Bahja Siddig Mohamed Mubarak Almaki Amna Moukhyer Fawaz Yahya Masswadi Mofareh Salman Harubi Elias Yosef Modabish Talal Omar Khasawi Yaser Mohammed Hantool Mohammed Awaji Mohammed Madkhali Aziza Mukhayer 《Journal of Biosciences and Medicines》 2024年第6期64-84,共21页
The current study aimed to evaluate the first aid knowledge and general awareness of bleeding control, and their relations with different variables among the population of Jazan City, Saudi Arabia, in 2023. A cross-se... The current study aimed to evaluate the first aid knowledge and general awareness of bleeding control, and their relations with different variables among the population of Jazan City, Saudi Arabia, in 2023. A cross-sectional study was conducted in Jazan City, Saudi Arabia between April 2023 and May 2023. Participants, >13 years old, living in Jazan City, were self-enrolled. Data collection was carried out by distributing a self-reported online survey questionnaire via email and social media apps. A validated, pretested online self-report questionnaire was used for data collection, with data analysis performed using (MS) Excel 2022 and SPSS version 26. A Chi-square test was used to determine the association of sociodemographic variables and Bleeding Control (BC) knowledge with, significance set at p < 0.05. A total of 250 participants completed the questionnaire, predominantly aged between 16 - 25 years, with 152 (60.8%) being male, and about 90% being Saudi citizens. Only 53 (21.2%) participated in previous first aid training concentrating on bleeding control. Only 76 (30.4%) of participants had good knowledge, while 131 (52.4%) exhibited positive attitude towards BC first aid. There were no statistically significant associations between BC knowledge and age, gender, occupation, nationality, and education. However, a significant association was observed between previous BC training and knowledge (Chi-test = 40.373, d.f = 1, p = 0.000) at p < 0.05. Conclusion: The prevalence of poor knowledge of bleeding control among community members in Jazan City was high. The findings of this study should be carefully considered by various healthcare organizations to implement educational first-aid programs and activities aimed at enhancing community awareness and knowledge of bleeding control. 展开更多
关键词 INJURY Uncontrolled Bleeding first Aid Knowledge ATTITUDE Jazan City
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First-Principles Investigation of Charge Transfer Mechanism of B-Doped 3C-SiC Semiconductor Material
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作者 Abdullahi Alkali Dauda Muhammad Yusuf Onimisi +7 位作者 Adeyemi Joshua Owolabi Hameed Adeneyi Lawal Hassan Muhammad Gambo Bashir Mohammed Aliyu Surajo Bala Muhammad Lamido Madugu Muhammad Abdurrahman Nainna Johnson Akinade Bamikole 《World Journal of Condensed Matter Physics》 CAS 2024年第2期35-44,共10页
This study delves into the charge transfer mechanism of boron (B)-doped 3C-SiC through first-principles investigations. We explore the effects of B doping on the electronic properties of 3C-SiC, focusing on a 12.5% im... This study delves into the charge transfer mechanism of boron (B)-doped 3C-SiC through first-principles investigations. We explore the effects of B doping on the electronic properties of 3C-SiC, focusing on a 12.5% impurity concentration. Our comprehensive analysis encompasses structural properties, electronic band structures, and charge density distributions. The optimized lattice constant and band gap energy of 3C-SiC were found to be 4.373 Å and 1.36 eV respectively, which is in agreement with previous research (Bui, 2012;Muchiri et al., 2018). Our results show that B doping narrows the band gap, enhances electrical conductivity, and influences charge transfer interactions. The charge density analysis reveals substantial interactions between B dopants and surrounding carbon atoms. This work not only enhances our understanding of the material’s electronic properties, but also highlights the importance of charge density analysis for characterizing charge transfer mechanisms and their implications in the 3C-SiC semiconductors. 展开更多
关键词 first-Principles Calculations DFT Boron (B)-Doped 3C-SiC Charge Transfer
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Research Progress of Radical Treatment of Helicobacter Pylori Based on Drug Sensitivity Test as First-Line Treatment
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作者 Dong Luo Haidong Zhou +8 位作者 Changtai Luo Wei Wang Luchang Chen Wujia Yang Xianqi Qin Song Huang Wenzhao Zhang Jiahou Xu Jihua Wei 《Journal of Biosciences and Medicines》 2024年第8期30-39,共10页
Helicobacter pylori (HP) infection is a global problem that affects about half of the world’s population and requires sufficient attention in clinical and scientific work. Due to differences in economic and medical c... Helicobacter pylori (HP) infection is a global problem that affects about half of the world’s population and requires sufficient attention in clinical and scientific work. Due to differences in economic and medical conditions among countries around the world, there is currently no unified treatment plan for anti-HP. In China, empirical quadruple therapy is mainly used. With the abuse of antibiotics, many patients face the problem of secondary eradication after failure, and the resistance rate of HP is gradually increasing. After eradication failure, drug sensitivity cultivation is carried out to choose sensitive antibiotics for treatment. A new strategy is currently needed to address how to improve the eradication rate of HP during the first eradication. This article aims to discuss the first-line treatment plans and research progress for eradicating HP based on drug sensitivity testing before eradication. Compared with traditional empirical therapies, treatment based on drug sensitivity results can effectively improve the eradication rate of HP, and reduce drug resistance rates, and adverse reactions, among other benefits. . 展开更多
关键词 Drug Susceptibility Test Helicobacter Pylori (HP) Infection first-Line Treatment HP Culture
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A Survey on the Current Situation of Prehospital First Aid about Knowledge, Belief and Behavior among University Students in Jingzhou
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作者 Tianyue Zhang Hong Zhou +1 位作者 Chenyang Xu Juan Zhou 《Open Journal of Applied Sciences》 2024年第5期1251-1261,共11页
Objective: To understand the current situation of prehospital first aid knowledge, attitude and behavior of university students in Jingzhou City. Methods: A prehospital first aid knowledge questionnaire and the conven... Objective: To understand the current situation of prehospital first aid knowledge, attitude and behavior of university students in Jingzhou City. Methods: A prehospital first aid knowledge questionnaire and the convenience sampling method were used to survey 307 university students in Jingzhou City. Results: The mean score of prehospital first aid knowledge of university students in Jingzhou City was 12.85 ± 2.643, the mean score of attitude was 50.73 ± 4.114, and the mean score of behavior was 39.05 ± 8.898;There was a statistically significant difference in the scores of prehospital first aid knowledge, attitude, and behavior of university students depending on whether or not they had received prehospital first aid training (P P Conclusion: Jingzhou University students have a positive attitude toward pre-hospital first aid, but the knowledge level and behavior are low, which suggests that the government, society and the school should create good conditions to promote the improvement of pre-hospital first aid knowledge and ability. 展开更多
关键词 Prehospital first Aid University Student KNOWLEDGE ATTITUDE BEHAVIORS
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Comparative Studies between Picard’s and Taylor’s Methods of Numerical Solutions of First Ordinary Order Differential Equations Arising from Real-Life Problems
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作者 Khalid Abd Elrazig Awad Alla Elnour 《Journal of Applied Mathematics and Physics》 2024年第3期877-896,共20页
To solve the first-order differential equation derived from the problem of a free-falling object and the problem arising from Newton’s law of cooling, the study compares the numerical solutions obtained from Picard’... To solve the first-order differential equation derived from the problem of a free-falling object and the problem arising from Newton’s law of cooling, the study compares the numerical solutions obtained from Picard’s and Taylor’s series methods. We have carried out a descriptive analysis using the MATLAB software. Picard’s and Taylor’s techniques for deriving numerical solutions are both strong mathematical instruments that behave similarly. All first-order differential equations in standard form that have a constant function on the right-hand side share this similarity. As a result, we can conclude that Taylor’s approach is simpler to use, more effective, and more accurate. We will contrast Rung Kutta and Taylor’s methods in more detail in the following section. 展开更多
关键词 first-Order Differential Equations Picard Method Taylor Series Method Numerical Solutions Numerical Examples MATLAB Software
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论古代希腊宗教中的first-fruits——从极北人送给提洛岛的供物说起 被引量:1
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作者 张良军 《浙江外国语学院学报》 2018年第6期84-92,共9页
first-fruits是古代希腊宗教献祭中常见的一种祭品,它有着丰富的内涵和象征意义,与现代意义上的first-fruits存在很大差异,把它仅仅理解为收获后的初果实际上是一种误读。古代希腊宗教中的first-fruits更强调对神祇的虔敬,并且在不同的... first-fruits是古代希腊宗教献祭中常见的一种祭品,它有着丰富的内涵和象征意义,与现代意义上的first-fruits存在很大差异,把它仅仅理解为收获后的初果实际上是一种误读。古代希腊宗教中的first-fruits更强调对神祇的虔敬,并且在不同的语境下,它的能指呈现出多样性。厄琉西斯first-fruits法令的颁布改变了献祭first-fruits的原始性质,把firstfruits变成雅典强制盟邦缴纳的宗教赋税什一税,法令体现出雅典与提洛同盟中其他城邦之间的不平等关系。 展开更多
关键词 古希腊宗教 first-fruits供物 极北人 厄琉西斯first-fruits法令
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数据分布型sort-first并行图形绘制系统的研究与实现 被引量:11
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作者 金哲凡 林海 石教英 《计算机研究与发展》 EI CSCD 北大核心 2004年第2期376-382,共7页
sort first体系结构常用来构建高性能并行图形绘制系统 基于immediate mode的数据集中型sort first系统 ,对网络带宽高度依赖 ,网络带宽和归属计算易成为系统瓶颈 提出了一个基于retain mode的数据分布型并行绘制系统 ,工作原理是将... sort first体系结构常用来构建高性能并行图形绘制系统 基于immediate mode的数据集中型sort first系统 ,对网络带宽高度依赖 ,网络带宽和归属计算易成为系统瓶颈 提出了一个基于retain mode的数据分布型并行绘制系统 ,工作原理是将几何数据分布于绘制结点 ,并利用帧间相似性动态调整绘制结点上的数据分布以适应视角的改变 ,有效地降低了数据分布所需的传输开销 系统利用Cell结构来控制并行粒度 展开更多
关键词 SORT-first 并行绘制 数据分布 粒度 帧间相似性
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FIRST和FOLLOW集合的并行算法设计 被引量:1
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作者 孙玉强 刘三阳 +1 位作者 张英丽 马正华 《计算机工程》 EI CAS CSCD 北大核心 2004年第21期71-73,125,共4页
描述了多处理机环境中 FIRST 和 FOLLOW 集合求解的一种并行处理方法,并讨论了 FIRST 和 FOLLOW 集合的并行算法设计思想和它的实现策略,在构造文法 G 的 LL(1)分析表以及判定文法 G 是否 LL(1)文法时,求解 FIRST 和 FOLLOW 集合是很重... 描述了多处理机环境中 FIRST 和 FOLLOW 集合求解的一种并行处理方法,并讨论了 FIRST 和 FOLLOW 集合的并行算法设计思想和它的实现策略,在构造文法 G 的 LL(1)分析表以及判定文法 G 是否 LL(1)文法时,求解 FIRST 和 FOLLOW 集合是很重要的内容,由于文法中终结符和非终结符个数很多,考虑 FIRST 和 FOLLOW 集合的并行处理方法,对并行编译处理和提高效率有其理论和现实意义。 展开更多
关键词 first集合 FOLLOW集合 关系矩阵 并行算法
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基于绘制历史的sort-first集群绘制负载平衡方法 被引量:1
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作者 沈兵虎 金哲凡 潘瑞芳 《计算机应用》 CSCD 北大核心 2006年第12期2843-2847,共5页
负载平衡对sort-first集群并行绘制系统的性能有很大影响,但静态负载平衡方法适应性较差。而动态方法中,基于几何数据遍历的方法不具备实用性,基于粗粒度几何数据组织的方法在实际中得到应用,但依赖于对几何数据的预处理。为此,提出了... 负载平衡对sort-first集群并行绘制系统的性能有很大影响,但静态负载平衡方法适应性较差。而动态方法中,基于几何数据遍历的方法不具备实用性,基于粗粒度几何数据组织的方法在实际中得到应用,但依赖于对几何数据的预处理。为此,提出了一种实用的、基于绘制历史的负载平衡方法:它不依赖于几何数据,用以前帧的绘制时间和负载分布信息作为未来帧绘制负载分配计算的输入。在集群绘制平台上的测试和比较表明,该方法有很好的效果。 展开更多
关键词 集群绘制 sort—first 负载平衡 绘制历史
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基于有向图的FIRST集合求解算法
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作者 卢伟 李堂秋 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1998年第4期488-492,共5页
引入文法的首符集图概念,据此提出一种求解上下文无文法FIRST集合的有效算法.
关键词 首符集图 first集合 数据结构 有向图
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Correlation between Polymorphism of Neuropeptide Y Gene and Traits at First Laying of Wenchang Chicken
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作者 朱文奇 李慧芳 +5 位作者 吴蓉蓉 宋卫涛 徐文娟 于吉英 肖小君 陈宽维 《Animal Husbandry and Feed Science》 CAS 2009年第2期5-7,12,共4页
[ Objective] The paper presents the polymorphism of neuropeptide Y gene (NPY) and its relationship with traits at first laying in Wen- chang chicken in order to provide information for breeding of high-yielding Wenc... [ Objective] The paper presents the polymorphism of neuropeptide Y gene (NPY) and its relationship with traits at first laying in Wen- chang chicken in order to provide information for breeding of high-yielding Wenchang chicken. [Method] The polymorphism of NPYgene at Dra I site was detected by PCR-RFLP, and the genotypes and the genetic stability were determined. The correlation between the polymorphism and traits at first laying (age, body weight and egg weight) was also analyzed. [Result] There were three kinds of genotype of NPYgene at Dra I site in Wenchang chicken, designated as AA, AB and BB; the distribution of these genotypes was consistent with the Hardy -Weinberg law; age and egg weight were not significantly different among the three genotypes ( P 〉0.05), and body weight was extremely significantly different ( P 〈0.01 ). [ Conclusion] The NPYgene of Wenchang chicken is in Hardy -Weinberg equilibrium at Dra I site, and its genetic polymorphism affects body weight at first laying. 展开更多
关键词 Wenchang chicken NPY gene Traits at first laying
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语言中“近取诸身”与“Me-First Orientation”的认知比较研究 被引量:1
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作者 朱晓琴 《西南科技大学学报(哲学社会科学版)》 2008年第3期82-86,共5页
"近取诸身"是中国古人许慎提出的,"Me-First Orientation"是当代英国人Cooper&Ross提出的,是认知方式,也是语言现象。"近取诸身"的认知方式主要是隐喻和转喻,"Me-First Orientation"主要... "近取诸身"是中国古人许慎提出的,"Me-First Orientation"是当代英国人Cooper&Ross提出的,是认知方式,也是语言现象。"近取诸身"的认知方式主要是隐喻和转喻,"Me-First Orientation"主要是以典型人物作为概念参照点;"近取诸身"语言现象表现为人体或与人体相关的词用于其它事物,因而是词义发展的动因;"Me-First O-rientation"则为解释语言中一些词汇固定的顺序提供了解释依据。 展开更多
关键词 近取诸身 Me—first ORIENTATION 认知方式 比较研究
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The Effect of Queuing Mechanisms First in First out (FIFO), Priority Queuing (PQ) and Weighted Fair Queuing (WFQ) on Network’s Routers and Applications 被引量:4
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作者 Mustafa El Gili Mustafa Samani A. Talab 《Wireless Sensor Network》 2016年第5期77-84,共8页
The paper presents the simulation results of the comparison of three Queuing Mechanisms, First in First out (FIFO), Priority Queuing (PQ), and Weighted Fair Queuing (WFQ). Depending on their effects on the network’s ... The paper presents the simulation results of the comparison of three Queuing Mechanisms, First in First out (FIFO), Priority Queuing (PQ), and Weighted Fair Queuing (WFQ). Depending on their effects on the network’s Routers, the load of any algorithm of them over Router’s CPUs and memory usage, the delay occurred between routers when any algorithm has been used and the network application throughput. This comparison explains that, PQ doesn’t need high specification hardware (memory and CPU) but when used it is not fair, because it serves one application and ignore the other application and FIFO mechanism has smaller queuing delay, otherwise PQ has bigger delay. 展开更多
关键词 Queuing Mechanisms QoS first in first out (FIFO) Priority Queuing (PQ) Weighted Fair Queuing (WFQ)
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基于传递闭包的First集合的求解算法
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作者 田胜利 李娟 《许昌学院学报》 CAS 2007年第2期103-106,共4页
介绍了求解First集合的传统算法和求解传递闭包的Warshall算法.针对Warshall算法进行改进,减少了整个运算过程的赋值环节.并把改进后的Warshall算法应用到First集合的求解算法中.与传统的First集合的求解算法相比,降低了时间复杂度,提... 介绍了求解First集合的传统算法和求解传递闭包的Warshall算法.针对Warshall算法进行改进,减少了整个运算过程的赋值环节.并把改进后的Warshall算法应用到First集合的求解算法中.与传统的First集合的求解算法相比,降低了时间复杂度,提高了运算效率. 展开更多
关键词 传递闭包 WARSHALL算法 first集合
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Warm Dark Matter and the Formation of First Galaxies 被引量:2
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作者 Bruce Hoeneisen 《Journal of Modern Physics》 2022年第6期932-948,共17页
By numerical integration of hydro-dynamical equations, we study the formation of elliptical and spiral galaxies starting from primordial linear density-velocity-gravitational perturbations. Both dark matter and baryon... By numerical integration of hydro-dynamical equations, we study the formation of elliptical and spiral galaxies starting from primordial linear density-velocity-gravitational perturbations. Both dark matter and baryons are included. Warm dark matter perturbations acquire two low mass cut-offs: the free-streaming cut-off due to the power spectrum free-streaming cut-off factor &tau;<sup>2</sup>(k), and the velocity dispersion cut-off. The Press-Schechter mass distribution does not include velocity dispersion, and should not be used below the velocity dispersion cut-off mass. From the formation of first galaxies and reionization, we estimate limits on the non-relativistic warm dark matter velocity dispersion at expansion parameter , with . 展开更多
关键词 Warm Dark Matter first Galaxies first Stars Population III Stars Reioniza-tion
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Arrival time measurements of first arrival phases P and PKIKP using the method of fixed scale wavelet transformation ratio
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作者 何小波 周蕙兰 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2005年第4期410-418,499,共10页
The arrival times of first teleseismic phases are difficult to be measured precisely because of slowly and gradually changed onsets and weak amplitudes. The arrival times measured manually are usually behind the real ... The arrival times of first teleseismic phases are difficult to be measured precisely because of slowly and gradually changed onsets and weak amplitudes. The arrival times measured manually are usually behind the real ones. In this paper, using the ratio method of fixed scale wavelet transformations improved by us, the arrival times for the first arrival phases (such as P and PKIKP) at the teleseismic and far-teleseismic distances were measured. The results are reasonable and reliable based on the analysis and discussion of the reliabilities and errors. 展开更多
关键词 Morlet wavelet wavelet transformation ratio first arrival phase first arrival time signal to noise ratio
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The Role of First Language in the Second Language Acquisition
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作者 李永秀 薛薇 《海外英语》 2012年第10X期243-245,共3页
In the linguistic field,L1transfer is a complex and controversial field in second language acquisition.In this article,Firstly,it will discuss some historical theories of L1 transfer.Secondly,it will analyze some mani... In the linguistic field,L1transfer is a complex and controversial field in second language acquisition.In this article,Firstly,it will discuss some historical theories of L1 transfer.Secondly,it will analyze some manifestations of L1 transfer.Thirdly,it will explain the struc tural and the nonstructural factors in L1 transfer.Fourthly,it will discuss the problems in the study of L1transfer.Finally,it will give some my opinions of L1transfer. 展开更多
关键词 the ROLE first LANGUAGE SECOND LANGUAGE acquisitio
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