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1.
开展智慧化阅读推广,紧跟时代步伐,有效提升读者多重阅读体验和满意度,增强智慧化阅读推广的价值,促进智慧化阅读推广服务的有效化、规范化、科学化、常态化、长期化发展,已成为当前阅读推广研究中一个重要的切入点。文章基于智慧化阅读研究,结合"新媒体"高新技术环境,提出智慧化阅读推广的内容分析、具体实施、环境构建、推广评估与效果、推广改进等几个方面组成的以读者为中心的核心服务体系。本文分析了智慧化阅读基本方面,以我校图书馆实际运用推广效果,智慧化阅读存在的优、劣势及相应的对策。  相似文献   
2.
Many argue that digital technologies have the potential to enhance the teaching and learning of mathematics. However, the availability of technology is not sufficient to realise this potential. The study reported takes a detailed approach to investigate the utility of the particular offerings of the available technologies in the teaching and learning of a specific area of mathematics, functions. Sixteen affordances identified in the data are described. The complexity of the process involved in resolving a situation where particular affordances would be useful so as they are perceived and enacted is detailed. Finally, a grounded theory framework arising from the data analysis from this study that can be used to explain, predict and guide action in other digital environments is presented.  相似文献   
3.
BackgroundConsidering the growing participation of woman in the labor market and the high prevalence of the musculoskeletal disorders (MSD) in the footwear industry workers, the aim of this study was to evaluate and compare female and male footwear industry workers in relation to their demographics, occupational characteristics, stress levels, MSD symptoms prevalence, physical activity levels, alcohol and tobacco use.MethodsThe study included 175 female and 182 male footwear industry workers. Data was collected using the Perceived Stress Scale – 10, the Standardized Nordic Questionnaire, the International Physical Activity Questionnaire, the Alcohol Use Disorders Identification Test, and the Fagerstrom test for Nicotine Dependence.ResultsThe female workers were younger, had less time in the company and in the current job. They reported more stress (p = 0.001), had less time for physical activity (p = 0.004), higher prevalence of MSD symptoms in the last 12 months (p = 0.003), and consumed less alcohol (p = 0.006) than the male workers.ConclusionsFemale and male footwear industry workers presented significant differences in their demographics, occupational characteristics, stress levels, MSD prevalence, physical activity levels, alcohol and tobacco use. These differences should be taken into consideration in the implementation of intervention programs for optimum outcomes.Relevance to industryFemale footwear industry workers were more stressed, presented higher prevalence of MSD symptoms, and reported less time for physical activity than male footwear industry workers. The differences between male and female workers should be taken into consideration in the implementation of MSD prevention programs.  相似文献   
4.
This paper reports the preparation and the evaluation of the performance of Ni-based powder catalysts with low nickel loading on the CO2 methanation reaction, that is an integral part of the power-to-gas (PtG) technology. CeO2, CeZrO4 and CeO2/SiO2 were selected as possible supports, and the results of this first screening pointed out that 10%Ni/CeO2 catalyst could offer the best reaction performances because of ceria's peculiar characteristics. Moreover, the promotion of this promising formulation with the addition of a small amount of noble metals (Pt, Ru, Rh) was investigated, showing that platinum in particular can enhance the catalyst performances. A further study related to the noble metal loading pointed out that platinum and ruthenium have a different optimum loading condition: this result, together with the activity tests performed on monometallic formulations with only the noble metal, suggested that the two metals are able to catalyse two different reactions, thus promoting two different reaction mechanisms.  相似文献   
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6.
A series of bi-metallic layered double hydroxide derived materials, containing a fixed amount of Ni promoted with various amounts of Fe were obtained by co-precipitation. The synthesized materials were characterized by X-ray diffraction (XRD), temperature-programmed reduction (H2-TPR), temperature-programmed desorption of CO2 (CO2-TPD), elemental analysis and low temperature N2 sorption and tested as catalysts in CO2 methanation at atmospheric pressure. The obtained results confirmed the formation of mixed nano-oxides after thermal decomposition of the precursor and suggest successful introduction of both nickel and iron into the layers of Layered Double Hydroxides (LDHs). The introduction of Fe into the layered double hydroxides changed the interaction between Ni and supports matrix as proven by temperature programmed reduction (H2-TPR). The introduction of low amount of iron influenced positively the catalytic activity in CO2 methanation at 250 °C, with CO2 conversion increasing from 21% to 72% with CH4 selectivity ranging from 97 to 99% at 250 °C. No other products, except CH4 and CO were registered during the experiments. In order to enhance the catalytic activity a non-thermal plasma created by dielectric barrier discharge was applied. The obtained results prove that plasma could replace the need of heating the reactor in a dynamic system working temporarily when excess energy is available.  相似文献   
7.
面源红外诱饵使用的过程中,合理有效的干扰策略是干扰红外制导导弹的关键,针对这一问题,通过理论分析与仿真模拟相结合得到面源红外诱饵对抗红外制导导弹的干扰策略。首先以红外成像制导导弹为例,介绍红外制导导弹的仿真模型,然后将攻击过程分为锁定前与锁定后,以命中率为评价指标,得到两个阶段下的最佳干扰策略,包括诱饵的最佳释放时机、释放间隔以及载机应采取的机动动作等。  相似文献   
8.
Research was undertaken to understand how to provide the most appropriate support for novice designers in engineering design. However, how designers apply their experience and knowledge is not understood and further research in this area is required. This paper describes an observational study to understand how novice and experienced designers approach design tasks. Electronic Publication  相似文献   
9.
Micro assembly injection moulding   总被引:1,自引:0,他引:1  
Injection moulding is established as one of the most common manufacturing processes of thermoplastics due to its high degree of automation and the short cycle times. Micro injection moulding is a rapidly growing technology that allows for the efficient production of very complex micro parts in high series. The “Market Analysis for Microsystems II 2002–2005” of the Nexus Task Force anticipates a yearly growth in the field of micro system technology of about 20% (Wechsung et al. 2002). This study identifies in addition to the continuous miniaturization the growing use of polymers in micro systems (Schneider et al. 2001). No other material group offers this wide range of material properties and permits to choose processing parameters and application properties according to necessities (Gächter 2000). While the production processes of micro technical components are mainly controllable, the assembly of these components to hybrid micro systems is a bottleneck to the industrial large scale production. The assembly itself represents a large fraction of the added product value and gains in importance with growing complexity and miniaturization of the systems.  相似文献   
10.
用PB和ORACLE方法实现身份证号升位   总被引:1,自引:0,他引:1  
陆波 《信息技术》2003,27(6):98-99
在对人员的管理工作中 ,需经常使用姓名和身份证号来进行人员检索。身份证号所具有的唯一性 ,决定了它成为表征一个人信息的准确特征。原有的 15位身份证号存在着“2 0 0 0年”问题 ,需升至 18位。本文分别用PB和ORACLE两种语言方式 ,讲述了实现身份证号升位的方法。  相似文献   
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