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921.
依据国际数据管理协会数据管理知识体系(DMBOK)中的数据质量管理过程,分析了电动汽车多源信息
决策支持系统中的数据特点以及建设中存在的问题,提出改进建议,并初步构建适用于电动汽车多源信息决策支持系
统的数据质量管理流程。 相似文献
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A previous study showed that pairs of students interacting in a second language produced more words when they were assigned a fictitious expert position in a specific competence dimension than when they were assigned a nonexpert position. It has also been shown that the usual level of expertise has an impact on the assigned fictitious expertise effect. The present study was designed to determine whether the processing capacity allotted to the current task could partly determine performance. A given position of expertise may demand a large or small attentional capacity. Two experiments were conducted using a dual-task paradigm. As expected, the different expertise positions led to different reaction times on the secondary task. The second experiment showed that the impact of assigning a position of expertise to students depends on their usual academic standing. This study supports the idea that in interactive situations, performance variations as a function of the expertise position can be partially explained by differences in the processing resources allocated to the task. Implications for teaching are discussed. 相似文献
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Yunlong CHENG Shu LIAN Shuhui LI Yusheng LU Jie WANG Xiaoxiao DENG Shengyi ZHAI Lee JIA 《Journal of Zhejiang University. Science. B》2022,23(11):943
ObjectivePrimary tumor treatment through surgical resection and adjuvant therapy has been extensively studied, but there is a lack of effective strategies and drugs for the treatment of tumor metastases. Here, we describe a functional product based on a combination of compounds, which can be used as an adjuvant therapy and has well-known mechanisms for inhibiting cancer metastases, improving anti-cancer treatment, and enhancing immunity and antioxidant capacity. Our designed combination, named MVBL, consists of four inexpensive compounds: L-selenium-methylselenocysteine (MSC), D-α-tocopheryl succinic acid (VES), β-carotene (β-Ca), and L-lysine (Lys).MethodsThe effects of MVBL on cell viability, cell cycle, cell apoptosis, cell migration, cell invasion, reactive oxygen species (ROS), and paclitaxel (PTX)-combined treatment were studied in vitro. The inhibition of tumor metastasis, antioxidation, and immune enhancement capacity of MVBL were determined in vivo.ResultsMVBL exhibited higher toxicity to tumor cells than to normal cells. It did not significantly affect the cell cycle of cancer cells, but increased their apoptosis. Wound healing, adhesion, and transwell assays showed that MVBL significantly inhibited tumor cell migration, adhesion, and invasion. MVBL sensitized MDA-MB-231 breast cancer cells to PTX, indicating that it can be used as an adjuvant to enhance the therapeutic effect of chemotherapy drugs. In mice, experimental data showed that MVBL inhibited tumor metastasis, prolonged their survival time, and enhanced their antioxidant capacity and immune function.ConclusionsThis study revealed the roles of MVBL in improving immunity and antioxidation, preventing tumor growth, and inhibiting metastasis in vitro and in vivo. MVBL may be used as an adjuvant drug in cancer therapy for improving the survival and quality of life of cancer patients. 相似文献
926.
为剖析技术创业企业商业模式创新多重前因的联动效应,基于商业模式冰山理论构建了商业模式创新的前因要素模型,以31家技术创业企业为样本,采用模糊集定性比较分析方法,分析了技术创业企业商业模式创新多重前因的联动效应。研究结果表明:(1)技术创业企业商业模式创新具有"多重并发"和"殊途同归"的特点,单一要素难以构成商业模式创新的必要条件;(2)网络嵌入与资源整合能力的协同作用对技术创业企业商业模式创新至关重要;(3)在高度的环境不确定情况下,资源整合能力和机会识别能力的协同作用,以及网络嵌入和战略柔性的协同作用是技术创业企业商业模式创新的重要途径。本研究进一步发展了商业模式冰山理论,丰富了商业模式创新前因的研究成果,为解释既有研究的分歧提供了新视角,也为技术创业企业根植自身情境实现商业模式创新提供了理论指导。 相似文献
927.
资源发现与交互技术是普适计算的基础。通过在系统级和应用级分析资源发现与交互技术需要解决的问题,在此基础上对现有的协议进行横向比较分析,包括资源描述、发布、查找、状态质询、选择、交互,以及异构性、安全性、自动配置、QoS等方面。基于比较分析结果提出了目前还没有解决的具体问题。 相似文献
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Averil Coxhead Emma McLaughlin Aleeshea Reid 《Journal of Vocational Education & Training》2019,71(2):175-200
Learners in the trades are faced with learning a large amount of technical vocabulary along with the content of their field, but they do not tend to encounter this language outside their courses of study. This technical vocabulary is a core element in their developing knowledge of their trade and their learner identity. This article focuses first on identifying technical vocabulary in Fabrication using specialised written and spoken corpora, and through extensive checking with experts in the field as well as reference sources. A technical word list of 1079 types was developed, along with a list of common abbreviations and their meanings and a list of proper nouns. The technical word list covers over 30% of the vocabulary in the written Fabrication corpus and just over 9% of the spoken Fabrication corpus. The second part of the article discusses this vocabulary in light of the concept of vocational thresholds and provides suggestions for incorporating the word list into pedagogy, including an apprenticeship approach in which a focus on literacy/literacy acquisition is embedded into content teaching. Suggestions for future research are also included. 相似文献