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1.
ABSTRACT

The concept of digital game-based learning (DGBL) evolves rapidly together with technological enhancements of virtual reality (VR) and smart phones. However, the mental workload (MWL) that VR-training applications demand and motivational qualities originating from user experience (UX) should be identified in order to create effective and enjoyable training/learning challenges that fit with individual users’ capabilities. This study examined the effects of reality-based interaction (RBI) and VR on measures of student motivation and MWL, in a mental arithmetic game for secondary school pupils. In a randomised controlled trial with sixty school children, a mental arithmetic game was tested with three different interaction and two different presentation methods – VR RBI, VR head-mounted-display tapping and tablet flick-gesture. Results found a significant effect of RBI on MWL but no differences in enjoyment of training were found between VR-experience and tablet training-experience. In fact, adding the gaming-context to the mental arithmetic task created an enjoyable, motivating experience regardless of presentation or interaction-style.  相似文献   
2.
Interest in developing high-performance blends for niche applications has grown significantly in efforts to meet ever-increasing harsh environment demands. In this work, four model poly(aryl-ether-ketone)/polybenzimidazole (PAEK/PBI) blends were chosen to study the influence of premixing methods, processing, and matrix polymers, on their mechanical properties. Among the model poly(ether ether ketone) (PEEK) and PBI blends, mechanical properties are greatly enhanced by melt premixing. The molding process mainly affects the matrix crystallinity, which in turn greatly influences fracture toughness of the blend. Poly(ether ketone ketone) (PEKK) and PBI blend exhibits a slightly lower tensile strength and fracture toughness than PEEK/PBI due to the differences in inherent properties of PEEK and PEKK matrices and their interfacial interaction with PBI. The processing−structure–property relationship of PAEK/PBI blends is established to help guide optimal design of high-performance polymer blends for structural applications. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48966.  相似文献   
3.
Polymers containing a certain amount of long-chain-branching (LCB) structure are expected to possess improved mechanical properties over those of the linear structure counterpart. However, fundamental knowledge on the structure–property relationship in LCB containing polypropylene (PP) is still illusive. In the present study, a set of model PP systems containing an increasing molar fraction of LCB (5–19 mol%) were prepared by reactive extrusion to determine how LCB content may influence the scratch behavior of PP. It is shown that with only 5 mol% of LCB content in PP can improve resistance against scratch-induced fish-scale formation by over 25%. The improvement of scratch resistance is attributed to the increases in entanglement density in LCB-containing PPs, which is evidenced by their creep-recovery behavior. The present study demonstrates that the incorporation of LCB in PP leads to higher viscoelastic recovery and increased tensile strength, which account for the observed improvement in scratch performance. The usefulness of LCB in polymers for improving scratch performance is discussed.  相似文献   
4.
熟练地应用在建筑材料和技术进步方面所积累的知识能够帮助人们灵活运用材料和技术,进而为市民设计活动场所。与先进的建造技术结合,把不同的建设材料视为景观的构成系统和独立要素进行研究和掌握有利于在工程项目中加以利用。对建材和技术创新应用得比较好的例子之一是在建筑物上建造开阔的城市花园和公共空间。为此,欧林事务所开发和不断改进景观构成系统,虽然大部分不为使用者所见,却保证了混凝土的建筑结构之上的绿化茂盛的景观。此外,欧林事务所又研究和开发了一些新技术。利用浇注玻璃和压层玻璃作为室外景观的结构材料。景观设计工作在客户的需求、材料和技术中创造革新,也需要通过支持平凡的独特性,来创造持久、美观而实用的景观场所。  相似文献   
5.
The concept of territoriality and its relationship to the focus and substance of spatial planning is the subject of much interest at the present time and this paper seeks to contribute to the debate by stepping into the sea. The first part of the paper establishes a framework for considering the spatial planning implications of changing conceptions of territoriality, outlining key sources of territorial innovation and their implications in terms of the development of new units and styles of governance, new challenges for planning practice, and the potential for feedback informing the development of planning theory. The application of the framework is then illustrated in the second part of the paper with reference to the emerging field of maritime spatial planning and in particular to the pioneering work that is being undertaken in Europe. This work is testing established notions of territoriality by highlighting the strong and growing connections between the land and the sea. Here some of the key implications for future spatial planning practice are identified. These indicate that there is a growing recognition of the need for innovation in the territorial units of governance in maritime regions and in the themes, processes and methods of spatial planning in these areas. The paper concludes with some observations on the implications of these findings for the theory of spatial planning.  相似文献   
6.
More than 70 % of women with ovarian cancer are diagnosed with advanced-stage disease, which is initially treated with cytoreductive surgery, and combination chemotherapy with platinum-based compounds. Most patients initially respond to platinum-based therapy, but eventually up to 80 % of this responsive cohort becomes refractory due to the development of platinum resistance. This review discusses current and potential therapeutic approaches that exploit biomaterial-based applications to combat platinum resistance either by enhancing the delivery of platinum-based drugs or prodrugs, delivering other toxic non-platinum-based bioactive factors (by themselves or in combination with platinum-based drugs) or by delivering other bioactive factors that re-sensitize resistant ovarian cancer cells to these drugs. The types of materials that are used, the bioactive factors applied (i.e., drug or gene delivery), and the specific agents that are employed to target these types of cancer cells are discussed. We conclude that the unique attributes of biomaterial-based applications can be further explored toward overcoming platinum-resistant ovarian cancer as monotherapy, or in combination with other treatment strategies.  相似文献   
7.
Cyberart incorporates interactive systems within artistic practices. The foundation for a theory of artistic production and creativity becomes expanded on the basis of a biological implication that is not dependent solely on aesthetic judgment. To communicate with computers and their high performance software stimulates artists’ imagination and there are types of interface or hardware that connect the natural system (especially the body) to the internal life of computers.  相似文献   
8.
This article analyzes the possibilities of applying Continuous Improvement principles to the management and maintenance of academic library websites. Current practice is mapped onto Continuous Improvement principles, with evidence distilled from a United Kingdom national survey of academic library web practitioners. The survey data informs a website organizational framework and operational model. The framework describes the setting within which library websites are managed, while the model focuses on library specific aspects to the management and development of their site.  相似文献   
9.
An instrumented hot compression molding apparatus was fabricated to allow real-time monitoring and precise temperature control during the compaction and consolidation of large polyether ether ketone (PEEK) products. The objective was to determine the impact of controlled variables on the properties of the molded article. Four different strategies were designed to control the mold thermal profiles. The average crystallinity in a commercial molding process is restricted due to large thermal masses with low thermal conductivity. In contrast, this research was able to reduce the crystallinity range from 33% to 6% by developing a special controlled apparatus and implementing new processing methodologies. In this study, PEEK showed a significant increase in the modulus compared to typical values measured on commercially produced analogs, and a higher degree of property uniformity. In a single commercially molded PEEK billet, compressive modulus variability was 13% at room temperature, and 21% at 225°C. Properties of billets produced using the laboratory apparatus showed a reduction in variability to 2%.  相似文献   
10.
ABSTRACT: BACKGROUND: The 5-year survival rate for breast cancer among Korean women has increased steadily; however, breast cancer remains the leading cause of cancer mortality among women. One-carbon metabolism, which requires an adequate supply of methyl group donors and B vitamins, may affect the prognosis of breast cancer. This aim of this study was to investigate the associations of dietary intake of vitamin B2, vitamin B6 and folate before diagnosis on the prognosis of breast cancer. METHODS: We assessed the dietary intake using a food frequency questionnaire with 980 women who were newly diagnosed and histopathologically confirmed to have primary breast cancer from hospitals in Korea, and 141 disease progression events occurred. Cox's proportional hazard regression models were used to estimate the hazard ratio (HR) and 95% confidence interval (95% CI) adjusting for age, education, recruitment sites, TNM stage, hormone status, nuclear grade and total calorie. RESULTS: There was no significant association between any one-carbon metabolism related nutrients (vitamin B2, B6 and folate) and the progression of breast cancer overall. However, one-carbon metabolism related nutrients were associated with disease progression in breast cancer patients stratified by subtypes. In ER + and/or PR + breast cancers, no association was observed; however, in ER--/PR-- breast cancers, a high intake of vitamin B2 and folate statistically elevated the HR of breast cancer progression (HR = 2.28; 95% CI, 1.20-4.35, HR = 1.84; 95% CI, 1.02-3.32, respectively) compared to a low intake. This positive association between the ER/PR status and progression of the disease was profound when the nutrient intakes were categorized in a combined score (Pinteraction = 0.018). In ER--/PR-- breast cancers, high combined scores were associated with a significantly poor DFS compared to those belonging to the low score group (HR = 3.84; 95% CI, 1.70-8.71). CONCLUSIONS: In conclusion, our results suggest that one-carbon related nutrients have a role in the prognosis of breast cancer depending on the ER/PR status.  相似文献   
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