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Importance of Input and Interaction in Second Language Acquisition 被引量:3
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作者 秦英 《魅力中国》 2009年第28期64-65,共2页
Nowadays,SLA(Second Language Acquisition) is a hot topic and is attached great importance at both home and abroad.Input and interaction are taken as two very important factors have great impact on the learners' L2... Nowadays,SLA(Second Language Acquisition) is a hot topic and is attached great importance at both home and abroad.Input and interaction are taken as two very important factors have great impact on the learners' L2 acquisition level and quality.The former research on the above two factors is productive and a lot of research on the importance of input and interaction in SLA is being conducted.Krashen's Input Hypoth-esis and Long's Interaction Hypothesis are the two most influ-ential ones.This thesis first giv... 展开更多
关键词 Second Language Acquisition input INTERACTION
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Factor input structure,environmental policies,and the export quality upgrade:a perspective of heterogeneity 被引量:3
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作者 Jiayue Liu Jing Xie 《Chinese Journal of Population,Resources and Environment》 2018年第1期67-76,共10页
In the analysis of how environmental regulation affects the comparative advantage of trade,existing literature ignores industry's inherent heterogeneity, which draws remarkably different conclusions. In view of th... In the analysis of how environmental regulation affects the comparative advantage of trade,existing literature ignores industry's inherent heterogeneity, which draws remarkably different conclusions. In view of this, the paper analyzed the mechanism of environmental regulation on the export quality of different industries from the perspective of factor input structure heterogeneity. Based on the panel data of China's manufacturing industry, the paper used the system generalized method of moments method to examine the heterogeneity influence of environmental regulation on manufacturing export quality. The study found that, first, environmental regulation affected the export quality upgrade of the manufacturing sector through offset effect and compensation effect, and the direction of the impact would mainly depend on the industry's factor input structure. Second, for industries with larger fixed-asset investment(FAI) ratio in the factor input structure, the current environmental regulation policy was not conducive to the export quality upgrading of the industries. However, there was a significant U-shaped dynamic relationship between them. As environmental regulations became stricter, when regulatory stringency went beyond the inflection point, the policy would promote the upgrading of export quality. But for industries with smaller proportion of FAI, environmental regulation exerted a favorable impact on the export quality upgrade, following a J-shaped marginal growth curve.Third, for industries with different factor input structure, their export quality had been effectively upgraded as expected by factors like human capital investment, independent R&D, technology introduction, and foreign direct investment; but raising per capita capital stock and expanding enterprise size did not produce significant direct impact on export quality upgrade. These conclusions remained robust after using different measurement methods and replacing with other variables. Therefore, this paper suggests that governments should take industry heterogeneity into consideration and formulate differentiated hierarchical environmental policies.Besides, they should strengthen the enforcement of the current environmental regulation policies. By doing so, enterprises are forced to improve their technology and product quality so that they can better cope with rising compliance costs, eliminate backward industries, and resolve excess capacity. In this way, the economic structure would be transformed and upgraded from the supply side. 展开更多
关键词 Environmental regulation export quality factor input structure industry heterogeneity
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The Importance of Input and Interaction in SLA
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作者 党春花 《魅力中国》 2009年第28期14-15,共2页
As is known to us,input and interaction play the cru-cial roles in second language acquisition(SLA).Different linguis-tic schools have different explanations to input and interaction.Behaviorist theories hold a view t... As is known to us,input and interaction play the cru-cial roles in second language acquisition(SLA).Different linguis-tic schools have different explanations to input and interaction.Behaviorist theories hold a view that input is composed of stim-uli and response,putting more emphasis on the importance of input,while mentalist theories find input is a necessary condi-tion to SLA,not a sufficient condition.At present,social inter-action theories,which is one type of cognitive linguistics,sug-gests that besid... 展开更多
关键词 input interaction second language acquisition
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A Novel Approach for Inferring the Proportion of Terrestrial Organic Matter Input to Marine Sediments on the Basis of TOC:TN and δ<sup>13</sup>C<sub>org</sub>Signatures
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作者 Antonio Fernando Menezes Freire Marcelo Costa Monteiro 《Open Journal of Marine Science》 2013年第2期74-92,共19页
The ratio of total organic carbon to total nitrogen (TOC:TN) and the stable carbon isotope ratio of organic matter (δ13Corg) are widely applied for inferring the origin of organic matter (OM) in Quaternary marine sed... The ratio of total organic carbon to total nitrogen (TOC:TN) and the stable carbon isotope ratio of organic matter (δ13Corg) are widely applied for inferring the origin of organic matter (OM) in Quaternary marine sediments. A plot of TOC:TN vs. δ13Corg is useful for such studies but is strongly based on qualitative constraints. This study is based on the qualitative characterization of the source of Quaternary OM via analysis of TOC:TN and δ13Corg signatures, but also proposes a probability parameter, which combines both signatures, to infer the amount of Terrestrial OM Input (TOMI). This index provides a method for quantifying the proportion of terrestrial OM vs. marine OMin a more comprehensive manner. The TOMI index concept was applied to a study area in theJoetsuBasin, eastern margin of theJapanSea, where previous studies have characterized theOMfrom the Last Glacial Maximum (LGM) to the present. The upwards increase in TOC indicates thatOMproduction during the Holocene was higher than during the LGM. The enriched δ13Corg signature upwards and decrease in TOC:TN suggest predominantly marine phytoplankton OM during the Holocene. Throughout the LGM, low OM production with depleted δ13Corg values and high TOC:TN values in the sediments suggest a predominantly C3 terrestrial plant source for the OM. Using these data, it was possible to calculate a proxy for a sea level variation curve during that period and to investigate the influence of the proximity of the coastal line to the continental slope on the input of terrestrial material to the basin. The proposal provides information for the application of sequence stratigraphic concepts. The TOMI index could confirm that the proximity to the shoreline and shelf break has a strong influence on the input of terrestrial material during lowstand periods. 展开更多
关键词 δ13Corg Joetsu Basin Japan Sea Terrestrial Organic Matter input TOMI Index TOC:TN
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A Novel Three-Port Converter for Wide-input-voltage-range Application 被引量:10
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作者 CHEN Runruo WU Hongfei XING Yan 《中国电机工程学报》 EI CSCD 北大核心 2012年第27期I0015-I0015,191,共1页
提出一种适用于宽电压范围的H桥三端口变换器。在H桥升降压变换器的基础上引入变压器副边整流滤波电路,形成变换器的第3个输出端口,从而构造出H桥三端口变换器;变换器包括两个双向输入/输出端和一个隔离输出端,分别与输入源、蓄电... 提出一种适用于宽电压范围的H桥三端口变换器。在H桥升降压变换器的基础上引入变压器副边整流滤波电路,形成变换器的第3个输出端口,从而构造出H桥三端口变换器;变换器包括两个双向输入/输出端和一个隔离输出端,分别与输入源、蓄电池和负载相连,同时实现三者的功率控制;变换器的原边电路等效为H桥升降压变换器,可以适应输入源电压宽范围变化的应用需求。详细分析变换器的工作状态及开关模态,分析开关时序对变压器直流偏置电流的影响,提出优化的开关时序控制方式,最后通过实验验证理论分析的正确性。 展开更多
关键词 电压范围 应用程序 转换器 三端口 输入 可再生能源 发电系统 存储元件
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Vibration Control of A Flexible Marine Riser System Subject to Input Dead Zone and Extraneous Disturbances 被引量:1
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作者 ZHOU Li WANG Guo-rong WAN Min 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期271-284,共14页
An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control... An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller. 展开更多
关键词 adaptive backstepping control disturbance observer flexible marine riser input dead zone vibration control
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循证护理在降低肺癌患者PORT并发症中的应用效果
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作者 张德红 杨燕 +1 位作者 左靖芳 谷爱花 《医药前沿》 2024年第19期86-88,共3页
目的:评估循证护理在降低肺癌患者植入式静脉输液港(PORT)相关并发症中的应用效果。方法:选取2021年1月—2023年6月江苏省肿瘤医院确诊肺癌并行PORT植入化疗的150例患者,根据护理方式的不同分为对照组和观察组,每组75例。对照组给予常... 目的:评估循证护理在降低肺癌患者植入式静脉输液港(PORT)相关并发症中的应用效果。方法:选取2021年1月—2023年6月江苏省肿瘤医院确诊肺癌并行PORT植入化疗的150例患者,根据护理方式的不同分为对照组和观察组,每组75例。对照组给予常规护理,观察组给予循证护理。比较两组的并发症发生率、情绪状态、知识掌握度评分。结果:观察组PORT相关性并发症总发生率低于对照组,差异有统计学意义(P<0.05)。护理前,两组不良情绪评分比较,差异无统计学意义(P>0.05);护理后,观察组焦虑自评量表(SAS)、抑郁自评量表(SDS)评分低于对照组,差异有统计学意义(P<0.05)。观察组知识掌握度评分均高于对照组,差异有统计学意义(P<0.05)。结论:循证护理在降低肺癌患者PORT并发症发生率、改善患者心理状态和生活质量方面效果显著,值得临床中应用。 展开更多
关键词 肿瘤护理 循证医学 port并发症 心理状态
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Fuzzy identification of nonlinear dynamic system based on selection of important input variables
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作者 LYU Jinfeng LIU Fucai REN Yaxue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第3期737-747,共11页
Input variables selection(IVS) is proved to be pivotal in nonlinear dynamic system modeling. In order to optimize the model of the nonlinear dynamic system, a fuzzy modeling method for determining the premise structur... Input variables selection(IVS) is proved to be pivotal in nonlinear dynamic system modeling. In order to optimize the model of the nonlinear dynamic system, a fuzzy modeling method for determining the premise structure by selecting important inputs of the system is studied. Firstly, a simplified two stage fuzzy curves method is proposed, which is employed to sort all possible inputs by their relevance with outputs, select the important input variables of the system and identify the structure.Secondly, in order to reduce the complexity of the model, the standard fuzzy c-means clustering algorithm and the recursive least squares algorithm are used to identify the premise parameters and conclusion parameters, respectively. Then, the effectiveness of IVS is verified by two well-known issues. Finally, the proposed identification method is applied to a realistic variable load pneumatic system. The simulation experiments indi cate that the IVS method in this paper has a positive influence on the approximation performance of the Takagi-Sugeno(T-S) fuzzy modeling. 展开更多
关键词 Takagi-Sugeno(T-S)fuzzy modeling input variable selection(IVS) fuzzy identification fuzzy c-means clustering algorithm
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A Study on the Importance of Language Input in Second Language Acquisition(SLA)
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作者 闵瑞华 《海外英语》 2020年第23期275-277,284,共4页
Input theory as a theoretical foundation in language teaching plays an important role in SLA.Though a wealth of re⁃search has been done by linguists to demonstrate the importance of language input in SLA,little has be... Input theory as a theoretical foundation in language teaching plays an important role in SLA.Though a wealth of re⁃search has been done by linguists to demonstrate the importance of language input in SLA,little has been written about the type and amount of language input for successful SLA,especially its processing model while acquiring a second language.This paper first discusses the Krashen’s input hypothesis in language learning,and then an introduction to Chaudron’s processing model of in⁃put is made.In the final part,the author explains the acquisition process based on word acquisition and grammar acquisition and concludes that in the process of acquiring a second language,the language learners reconstruct a new cognitive model by taking in consistent comprehensible language input. 展开更多
关键词 language input SLA processing model of input acquisition process
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基于port write事件触发的RapidIO节点动态管理方法
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作者 费霞 高逸龙 《集成电路与嵌入式系统》 2024年第6期67-70,共4页
针对现有大规模的综合化电子信息系统中RapidIO节点管理实时性不强、CPU资源占用多的问题,提出了一种基于port write事件触发的RapidIO节点动态管理方法。该方法利用RapidIO交换芯片的port write包上报退网或者入网的节点信息,通过该信... 针对现有大规模的综合化电子信息系统中RapidIO节点管理实时性不强、CPU资源占用多的问题,提出了一种基于port write事件触发的RapidIO节点动态管理方法。该方法利用RapidIO交换芯片的port write包上报退网或者入网的节点信息,通过该信息动态管理RapidIO网络中的所有节点。工程应用实测结果表明,该方法实时性高,CPU资源占用少。 展开更多
关键词 port write包 RAPIDIO 动态管理 事件触发
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Basilic vein variation encountered during surgery for arm vein port:A case report
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作者 Cheng-Da Hu Rui Lv +3 位作者 Ya-Xin Zhao Ming-Hao Zhang Hong-Dou Zeng Yi-Wen Mao 《World Journal of Clinical Cases》 SCIE 2024年第12期2086-2091,共6页
BACKGROUND Venous variations are uncommon and usually hard to identify,and basilic vein variation is particularly rare.Basilic vein variation usually presents without any clinical symptoms and is often regarded as a b... BACKGROUND Venous variations are uncommon and usually hard to identify,and basilic vein variation is particularly rare.Basilic vein variation usually presents without any clinical symptoms and is often regarded as a benign alteration.This case was a patient with congenital basilic vein variation encountered during surgery for an infusion port.CASE SUMMARY We documented and analyzed an uncommon anatomical variation in the basilic vein encountered during arm port insertion.This peculiarity has hitherto remained undescribed in the literature.We offer remedial strategies for addressing this anomaly in the future and precautionary measures to circumvent its occurrence.We conducted a comprehensive review of analogous cases in the literature,offering pertinent therapeutic recommendations and solutions,with the aim of enhancing the efficacy and safety of future arm port implantations.CONCLUSION Venous variation is rare and requires detailed intraoperative and postoperative examination to ensure accuracy,so as not to affect subsequent treatment. 展开更多
关键词 Totally implantable venous access ports Arm ports Venous variation Postoperative breast cancer Systematic review Case report
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The Impact of Privatization on Terminal Efficiency: A Case Study of Tema Port
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作者 Bernard Kwei Tetteh Calvin Elorm Atsunyo Alex Boateng 《Journal of Transportation Technologies》 2024年第3期358-371,共14页
Port and terminal efficiency are of utmost importance to the container shipping industry due to their significance in enhancing the competitive advantage of ports within a region. Consequently, there have always been ... Port and terminal efficiency are of utmost importance to the container shipping industry due to their significance in enhancing the competitive advantage of ports within a region. Consequently, there have always been notable variations of studies around it. This paper analyzes the impact of privatization on terminal efficiency using the Port of Tema as a Case Study. The main objective of this paper is to analyze the efficiency trends of the public and private terminals in the port over the years. To achieve this objective, DEA-CCR methodology was employed to calculate the annual technical efficiency trends of the private and public terminals using four input variables and three output variables. The main results of the paper indicated that the public and private terminals were efficient for multiple years. However, the efficiency scores over the years demonstrated inconsistency, exhibiting notable fluctuations. The findings of this study will aid policymakers across the region on policies relating to the efficiency and ownership structure of ports and terminals. 展开更多
关键词 PRIVATIZATION Terminal Efficiency DEA Tema port
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Incidence of Acute Allergic Conjunctivitis in Workers at the Port of Santos
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作者 Fernanda Daroz Paulo Colombo-Barboza Elizabeth Barbosa Oliveira-Sales +2 位作者 Edgar Maquigussa Guilherme Nôvoa Colombo-Barboza Mirian Aparecida Boim 《Occupational Diseases and Environmental Medicine》 2024年第4期265-272,共8页
Objective: To evaluate the incidence of acute atopic conjunctivitis in the port environment. Methods: This is a descriptive, retrospective study involving 365 worker patients from the Port of Santos and 365 patients n... Objective: To evaluate the incidence of acute atopic conjunctivitis in the port environment. Methods: This is a descriptive, retrospective study involving 365 worker patients from the Port of Santos and 365 patients not related with port activities (control group). All patients were seen at the same private hospital in the city of Santos. Data were obtained by reviewing the electronic medical records of each patient related to the admission exam (initial) and to any assistance due to ocular allergic symptoms (red eyes) between 2019 and 2021. The analyzed data included age, sex, port section (port workers), refraction, time of symptom onset, disease history, treatment, and clinical outcome. Data were statistically assessed by the Chi-square test. Results: All patents were male. The mean age (34 ± 12 vs 35 ± 11 years) and the prevalence of refractive errors were similar between groups. In contrast, ocular allergic symptoms were significantly higher in group of port workers (34%) compared with non-port workers (17%), p < 0.0001. Likewise, episodes related to ocular allergy were more frequent in port workers, p < 0.05. Workers with activities related to bulk handling were the most affected. Conclusions: The incidence of acute allergic conjunctivitis in port workers requires attention from health authorities. This may lead to prevention and a better understanding of the epidemiology of the disease. 展开更多
关键词 REFRACTION Allergic Conjunctivitis port Activities
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A Fractional-Order Ultra-Local Model-Based Adaptive Neural Network Sliding Mode Control of n-DOF Upper-Limb Exoskeleton With Input Deadzone
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作者 Dingxin He HaoPing Wang +1 位作者 Yang Tian Yida Guo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期760-781,共22页
This paper proposes an adaptive neural network sliding mode control based on fractional-order ultra-local model for n-DOF upper-limb exoskeleton in presence of uncertainties,external disturbances and input deadzone.Co... This paper proposes an adaptive neural network sliding mode control based on fractional-order ultra-local model for n-DOF upper-limb exoskeleton in presence of uncertainties,external disturbances and input deadzone.Considering the model complexity and input deadzone,a fractional-order ultra-local model is proposed to formulate the original dynamic system for simple controller design.Firstly,the control gain of ultra-local model is considered as a constant.The fractional-order sliding mode technique is designed to stabilize the closed-loop system,while fractional-order time-delay estimation is combined with neural network to estimate the lumped disturbance.Correspondingly,a fractional-order ultra-local model-based neural network sliding mode controller(FO-NNSMC) is proposed.Secondly,to avoid disadvantageous effect of improper gain selection on the control performance,the control gain of ultra-local model is considered as an unknown parameter.Then,the Nussbaum technique is introduced into the FO-NNSMC to deal with the stability problem with unknown gain.Correspondingly,a fractional-order ultra-local model-based adaptive neural network sliding mode controller(FO-ANNSMC) is proposed.Moreover,the stability analysis of the closed-loop system with the proposed method is presented by using the Lyapunov theory.Finally,with the co-simulations on virtual prototype of 7-DOF iReHave upper-limb exoskeleton and experiments on 2-DOF upper-limb exoskeleton,the obtained compared results illustrate the effectiveness and superiority of the proposed method. 展开更多
关键词 Adaptive control input deadzone model-free control n-DOF upper-limb exoskeleton neural network
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AGV Scheduling Optimization of Automated Port Based on Disruption Management
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作者 Ching-Kuei Kao Qi-Er Ke +1 位作者 King-Zoo Tang Peng-Jung Lin 《Journal of Transportation Technologies》 2024年第3期423-444,共22页
The recent rapid development of China’s foreign trade has led to the significant increase in waterway transportation and automated container ports. Automated terminals can significantly improve the loading and unload... The recent rapid development of China’s foreign trade has led to the significant increase in waterway transportation and automated container ports. Automated terminals can significantly improve the loading and unloading efficiency of container terminals. These terminals can also increase the port’s transportation volume while ensuring the quality of cargo loading and unloading, which has become an inevitable trend in the future development of ports. However, the continuous growth of the port’s transportation volume has increased the horizontal transportation pressure on the automated terminal, and the problems of route conflicts and road locks faced by automated guided vehicles (AGV) have become increasingly prominent. Accordingly, this work takes Xiamen Yuanhai automated container terminal as an example. This work focuses on analyzing the interference problem of path conflict in its horizontal transportation AGV scheduling. Results show that path conflict, the most prominent interference factor, will cause AGV scheduling to be unable to execute the original plan. Consequently, the disruption management was used to establish a disturbance recovery model, and the Dijkstra algorithm for combining with time windows is adopted to plan a conflict-free path. Based on the comparison with the rescheduling method, the research obtains that the deviation of the transportation path and the deviation degree of the transportation path under the disruption management method are much lower than those of the rescheduling method. The transportation path deviation degree of the disruption management method is only 5.56%. Meanwhile, the deviation degree of the transportation path under the rescheduling method is 44.44%. 展开更多
关键词 Automated port Disruption Management Automated Guided Vehicle Scheduling Dijkstra Algorithm
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Influence of heat input on the microhardness and microstructure of the welding interface between nickel-based alloy and low-alloy steel
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作者 ZHU Min 《Baosteel Technical Research》 CAS 2024年第3期33-38,共6页
The evolution of microstructure and local properties near the welding interface is essential for the service safety of dissimilar metal welded joints between nickel-based alloy(NA) and low-alloy steel(LA).In this work... The evolution of microstructure and local properties near the welding interface is essential for the service safety of dissimilar metal welded joints between nickel-based alloy(NA) and low-alloy steel(LA).In this work,NA filler metal was deposited on LA substrate under different heat inputs by tungsten inert gas(TIG) welding.Microstructural characterization and microhardness tests were carried out near the prepared cladding interfaces.Optical and scanning electron microscopes show the lack of evident hardening transition layer along the welding interface.As the heat input increases,the mean hardness of the deposited layer also increases remarkably due to the rising dilution rate.Microstructural characterization shows a significant composition gradient across the cladding interface,but the diffusion gradient is limited to a small range.Under high heat input,a planar grain zone is generated along the interface due to the large temperature gradient across the interface region. 展开更多
关键词 welding interface heat input MICROSTRUCTURE MICROHARDNESS
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Seroprevalence Survey of HIV and Hepatitis B Virus and Behavioral Characteristics among Heavy Truck Drivers along Port Sudan-Khartoum Highways
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作者 Sara S. Osman Adam A. Mattar Omnia M. Hamid 《Open Journal of Medical Microbiology》 2024年第1期11-22,共12页
The prevalence of human immunodeficiency virus (AIDS) and hepatitis B virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The pr... The prevalence of human immunodeficiency virus (AIDS) and hepatitis B virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The present study aimed to screen for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and behavioral characteristics among heavy truck drivers in Port Sudan. A cross-sectional study was conducted on 274 heavy truck drivers and their assistants who used the highway Port Sudan-Khartoum in Port Sudan city during 2019-2021. Data on behavioral characteristics and substance use habits were collected using a structured questionnaire, and an ELISA test was used to screen for HIV and HBV infections in the study participants. The chi-square test, odds ratio, and confidence intervals were used to find the association between behavioral characteristics and seropositive HIV/HBV. Of the 274 enrolled participants, the seroprevalence rates of HIV were 2.7% and HBV was 23.7%. Ninety-four (34.3%) of them had a history of high-risk sexual behavior outside of marriage;only two (0.7%) used condoms;14.2% of participants reported alcohol use;and 1.1% reported drug use. Univariate analysis revealed that having a sex history outside of marriage with ≥1 sex partner and never using a condom with a spouse or casual partner were significant risk factors for HIV and HBV among drivers. Fortunately, we found that most of the drivers reported low alcohol and drug use. Concerning this study, the seroprevalence of HIV and HBV is highly associated with a history of having sex outside of marriage and sexual behavior among truck drivers and assistances. Additional studies are needed to further investigate other STIs and behavioral characteristics associated with factors in truck drivers/assistance in different truck stop regions in Sudan. 展开更多
关键词 Sexual Transmitted Infection port Sudan Truck Drivers/Assistance
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Influence of heat input on microhardness and microstructure across the welding interface between stainless steel and low alloy steel
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作者 ZHU Min 《Baosteel Technical Research》 CAS 2024年第1期14-21,共8页
The welding interface is crucial to the service safety of dissimilar metal weld(DMW)joints between stainless steel(SS)and low alloy(LA)steel.Different status of welding interfaces was prepared by cladding SS consumabl... The welding interface is crucial to the service safety of dissimilar metal weld(DMW)joints between stainless steel(SS)and low alloy(LA)steel.Different status of welding interfaces was prepared by cladding SS consumables to LA steel substrates with different heat inputs via tungsten inert gas arc welding(TIG),followed by a series of microstructural characterizations and hardness tests.Results showed that a hardening and transition layer(TL)would be generated along the welding interface,and the width and hardening degree of the TL would increase with the heat input.Meanwhile,heavy load hardness tests showed that highly severe inhomogeneous plastic deformation and the microcrack would be generated in the interfacial region and the welding interface respectively in the highest heat input sample(1.03 kJ/mm).These results indicate that the increase in heat input would deteriorate the bonding performance of DMW joints.Further microstructural observations showed that the higher hardening degree of the highest heat input sample was mainly attributed to the stronger grain boundary,solution,and dislocation strengthening effects. 展开更多
关键词 welding interface transition layer heat input MICROSTRUCTURE hardness
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Dynamic Event-Triggered Consensus Control for Input Constrained Multi-Agent Systems With a Designable Minimum Inter-Event Time
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作者 Meilin Li Yue Long +2 位作者 Tieshan Li Hongjing Liang C.L.Philip Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期649-660,共12页
This paper investigates the consensus control of multi-agent systems(MASs) with constrained input using the dynamic event-triggered mechanism(ETM).Consider the MASs with small-scale networks where a centralized dynami... This paper investigates the consensus control of multi-agent systems(MASs) with constrained input using the dynamic event-triggered mechanism(ETM).Consider the MASs with small-scale networks where a centralized dynamic ETM with global information of the MASs is first designed.Then,a distributed dynamic ETM which only uses local information is developed for the MASs with large-scale networks.It is shown that the semi-global consensus of the MASs can be achieved by the designed bounded control protocol where the Zeno phenomenon is eliminated by a designable minimum inter-event time.In addition,it is easier to find a trade-off between the convergence rate and the minimum inter-event time by an adjustable parameter.Furthermore,the results are extended to regional consensus of the MASs with the bounded control protocol.Numerical simulations show the effectiveness of the proposed approach. 展开更多
关键词 Constrained input designable minimum inter-event time directed communication topology dynamic event-triggered mechanism MASs consensus control
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Function Evolution and Landscape Planning Strategy of Inland Rivers in Beilun Port City of Ningbo
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作者 ZHONG Guoqing 《Journal of Landscape Research》 2024年第1期12-16,21,共6页
In the history, the main roles of inland rivers in Beilun Port City of Ningbo were desalination,blocking tides, shipping, and flood control. Nowadays, with the continuous spread and deepening ofurbanization, the ecolo... In the history, the main roles of inland rivers in Beilun Port City of Ningbo were desalination,blocking tides, shipping, and flood control. Nowadays, with the continuous spread and deepening ofurbanization, the ecological environment of river courses has been destroyed. In the past, remediationmeasures based on engineering and technology played a certain role, but can not “cure the root cause”. Itshould respect the historical evolution process of river courses, and highlight the ecological service functionand leisure tourism value of river courses from the coordination perspective of urban and rural ecologicalenvironment, economic industries, society and culture in the planning ideas of ecology, production, andlife integration. Four aspects of the measures are as below: protecting and repairing the ecological matrixof river courses;building green space system and maintaining flood control functions through the waternetwork;protecting cultural heritage along the rivers;developing waterfront leisure tourism scenic area. 展开更多
关键词 Beilun port City Inland river Function evolution Landscape planning
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