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921.
区域自识别医用观片灯控制系统设计   总被引:1,自引:0,他引:1  
基于嵌入式控制技术,提出一种具有区域自识别功能的新型医用观片灯系统结构。该系统以超高亮白光LED构成分布均匀的LED阵列,通过嵌入式控制器识别X光片的规格及覆盖区域,并控制该区域的LED灯阵列发光。本系统所采用的分区LED灯光控制技术不仅可以有效节约电能,大幅延长观片灯寿命,而且还能改善医务工作者观察的舒适度。  相似文献   
922.
以ZY13Sens12SB传感器技术实验台为平台,以振动梁为对象,利用应变传感器检测振动梁的振动。给出了系统硬件设计原理框图、各模块之间的接口连接,通过调节实验台上音频振荡器的频率,达到调制和改变振动梁的振动频率,可实现振动梁以不同频率和幅度振动,利用示波器可实时观察振动波形。  相似文献   
923.
ABSTRACT

A review of existing Electronic Commerce adoption literature reveals that the prevailing theoretical frameworks implicitly assume that organizations are independent and have complete control over their decisions to adopt innovations. Given the fact that organizations are often constrained by and depend on their environment and exchange partners to survive, this paper proposes that Resource Dependency can either be a facilitator or inhibitor of the role of Technological, Organizational, and Environmental (TOE) motivating factors. Using 239 valid responses from supply chain managers in Jordan, the study found partial support for the role of Resource Dependency as a moderator. The findings provide insights on how Resource Dependency between partners drives different patterns of innovation acceptance among potential adopters, regardless of several technological and organizational motivations to innovate. The results suggest that predicting how innovation is diffused within a market needs a detailed understanding of the inter-dependence structure among the supply chain members.  相似文献   
924.
925.
This study examined the question, ‘What is the impact of a digital math intervention on secondary ELL students’ mathematical capabilities and perceptions of their future possibilities?’ The hypothesis was that through its direct effect on increasing students’ math ability and its indirect effect on increasing students’ perceived math self-efficacy, the digital intervention affects students’ perceptions of their functionings and future possibilities. A path analysis, with qualitative data nested into the design, was used to analyze the conceptualized relationships. The study was conducted with 50 ninth-and-10th-grade Hispanic students in a Colorado high school, over 6 months. The primary finding was that through its direct effect on increasing students’ math ability and its indirect effect on increasing students’ perceived math self-efficacy, the digital intervention improved students’ perceptions of their functionings and future possibilities. What this study specifically underscores is the importance of taking a coherent and purposeful approach toward the design of digital student-directed educational technology, especially for ELL students who may have specific learning needs.  相似文献   
926.
In recent years, educators and students are increasingly employing online collaboration applications such as Google Docs™ and PBWorks™ for group projects and assignments. Yet, the effectiveness of these emerging technologies has not been rigorously examined. Anchoring upon and informed by the existing literature, two design characteristics – sociability and visibility, and two human characteristics – gender and age, are focused on, which are salient in online collaboration applications. A field experiment was conducted to examine the direct and moderating effects of design and human characteristics on learning outcomes. The research found that sociability improved process satisfaction and positive social environment while visibility enhanced academic performance and solution satisfaction of learners. Males had higher solution satisfaction while older learners had higher academic performance. Moderating effects were also found. Both theoretical and practical implications are drawn. In particular, a rubric for online collaboration application selection for academic performance is conceived. This study provides empirical support for online collaboration application effectiveness in education which will augur well for future adoption, use and evolution.  相似文献   
927.
Recent technological developments made various many-core hardware platforms widely accessible. These massively parallel architectures have been used to significantly accelerate many computation demanding tasks. In this paper, we show how the algorithms for LTL model checking can be redesigned in order to accelerate LTL model checking on many-core GPU platforms. Our detailed experimental evaluation demonstrates that using the NVIDIA CUDA technology results in a significant speedup of the verification process. Together with state space generation based on shared hash-table and DFS exploration, our CUDA accelerated model checker is the fastest among state-of-the-art shared memory model checking tools.  相似文献   
928.
This paper presents a semiotic technique as a means of exploring meaning and understanding in interface design and use. This is examined through a study of the interaction between the ‘file’ metaphor and ‘save as’ command metaphor. The behaviour of these (from a functional or computational basis) do not exactly match, or map onto, the meaning of the metaphor. We examine both the denotation of a term to the user, i.e. its literal meaning to that person, and the term's connotations, i.e. any other meanings associated with the term. We suggest that the technique applied is useful in predicting future problems with understanding the use of metaphor at the interface and with designing appropriate signification for human-computer interaction. Variation in connotation was expected but a more fundamental difference in denotation was also uncovered. Moreover, the results clearly demonstrate that consistency in the denotation of a term is critical in achieving a good user understanding of the command.  相似文献   
929.
ABSTRACT

This study proposes design, uniqueness, and screen size as the key components of aesthetic appeal and investigates their role in influencing the use behaviour of current smartwatch users and purchase intentions of potential users. Hypotheses were tested using SmartPLS to analyze data collected from 377 current smartwatch users and 361 potential users. Design aesthetics was found to be the most important factor influencing the behavioural intentions of both user groups. Screen size and uniqueness had significant effects on current users’ use behaviour and potential users’ purchase intentions, respectively. Gender moderated the effect of design on the use behaviour of current smartwatch users, such that female users’ behaviour was more likely to be influenced than male users. A subsequent analysis on the moderating effect of brand revealed that the design aesthetics of smartwatches mattered more for Apple than Samsung in terms of promoting use behaviour.  相似文献   
930.
This study investigates how workers' gender, work experience, designated division, and appointment affect (i) their perception of information technology (IT) within the organisation, (ii) their self-perceived capacity in knowledge management (KM), and (iii) their perception of organisational performance (OP). Furthermore, the study also examines the correlation among the above three dimensions by using t-test, one-way Analysis of Variance (ANOVA), Pearson correlation and stepwise regression analysis. These results show a positive correlation among IT application, KM capacity, and OP. In addition, the study discovers that (i) adequate IT investment and acceptance will improve employees' KM capacity, (ii) appropriate IT investment and training and employees' knowledge replication ability can better predict organisational outcomes, and (iii) employees' KM capacity is a better predictor of OP than IT application. Results also show that personal factors do affect workers' perception of the organisation's IT application, their KM capacity, and overall OP.  相似文献   
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