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11.
ABSTRACT. This study is the first to investigate the amount and type of information about children's services described in Japanese public library websites, with particular reference to the Web pages intended for children, and the extent to which usability is taken into account in the design of these websites. Further, the study analyzes what kinds of content are more prevalent in children's services as described in Japanese public library websites in comparison with the actual delivery of these services. Finally, the study considers the usability of children's Web pages from the perspectives of how easy they are to read and understand. 相似文献
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Siqi Wang Mervin Zhao Changjian Zhang Sui Yang Yuan Wang Kenji Watanabe Takashi Taniguchi James Hone Xiang Zhang 《国家科学评论(英文版)》2020,7(2):248
Band structure determines the motion of electrons in a solid, giving rise to exotic phenomena when properly engineered. Drawing an analogy between electrons and photons, artificially designed optical lattices indicate the possibility of a similar band modulation effect in graphene systems. Yet due to the fermionic nature of electrons, modulated electronic systems promise far richer categories of behaviors than those found in optical lattices. Here, we uncovered a strong modulation of electronic states in bilayer graphene subject to periodic potentials. We observed for the first time the hybridization of electron and hole sub-bands, resulting in local band gaps at both primary and secondary charge neutrality points. Such hybridization leads to the formation of flat bands, enabling the study of correlated effects in graphene systems. This work may provide a novel way to manipulate electronic states in layered systems, which is important to both fundamental research and application. 相似文献
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Shuang Wang Chen-Yu Wang Pengfei Wang Cong Wang Zhu-An Li Chen Pan Yitong Dai Anyuan Gao Chuan Liu Jian Liu Huafeng Yang Xiaowei Liu Bin Cheng Kunji Chen Zhenlin Wang Kenji Watanabe Takashi Taniguchi Shi-Jun Liang Feng Miao 《国家科学评论(英文版)》2021,8(2)
Compared to human vision, conventional machine vision composed of an image sensor and processor suffers from high latency and large power consumption due to physically separated image sensing and processing. A neuromorphic vision system with brain-inspired visual perception provides a promising solution to the problem. Here we propose and demonstrate a prototype neuromorphic vision system by networking a retinomorphic sensor with a memristive crossbar. We fabricate the retinomorphic sensor by using WSe2/h-BN/Al2O3 van der Waals heterostructures with gate-tunable photoresponses, to closely mimic the human retinal capabilities in simultaneously sensing and processing images. We then network the sensor with a large-scale Pt/Ta/HfO2/Ta one-transistor-one-resistor (1T1R) memristive crossbar, which plays a similar role to the visual cortex in the human brain. The realized neuromorphic vision system allows for fast letter recognition and object tracking, indicating the capabilities of image sensing, processing and recognition in the full analog regime. Our work suggests that such a neuromorphic vision system may open up unprecedented opportunities in future visual perception applications. 相似文献
14.
A featured microchip owning three big reservoirs and long turned geometry channel was designed to improve the detection limit of DNA fragments by using floating electrokinetic supercharging (FEKS) method. The novel design matches the FEKS preconcentration needs of a large sample volume introduction with electrokinetic injection (EKI), as well as long duration of isotachophoresis (ITP) process to enrich low concentration sample. In the curved channel [∼45.6 mm long between port 1 (P1) and the intersection point of two channels], EKI and ITP were performed while the side port 3 (P3) was electrically floated. The turn-induced band broadening with or without ITP process was investigated by a computer simulation (using CFD-ACE+ software) when the analytes traveling through the U-shaped geometry. It was found that the channel curvature determined the extent of band broadening, however, which could be effectively eliminated by the way of ITP. After the ITP-stacked zones passed the intersection point from P1, they were rapidly destacked for separation and detection from ITP to zone electrophoresis by using leading ions from P3. The FEKS carried on the novel chip successfully contributed to higher sensitivities of DNA fragments in comparison with our previous results realized on either a single channel or a cross microchip. The analysis of low concentration 50 bp DNA step ladders (0.23 μg∕ml after 1500-fold diluted) was achieved with normal UV detection at 260 nm. The obtained limit of detections (LODs) were on average 100 times better than using conventional pinched injection, down to several ng∕ml for individual DNA fragment. 相似文献
15.
Takuya Sekiguchi Haruki Momma Masahiro Tsuchiya Kaoru Kuroki Kenji Kanazawa 《Journal of sports sciences》2018,36(16):1801-1807
Youth athletes are known to be at high risk of musculoskeletal (MSK) injuries. Children in developed countries are increasingly adopting a sedentary lifestyle. Although some risk factors related to sports activities have been reported, the effect of lifestyle (i.e. screen time behaviour) on MSK pain in youth athletes is not well known. This study aimed to examine the association of game playing and TV viewing with MSK pain among youth athletes. A self-administered questionnaire was mailed to youth athletes belonging to the Miyagi Amateur Sports Association. The final study population included 6,143 youth athletes (male, 71.1%; age range, 6–15 years). Multiple logistic regression analysis was used to examine the association of game playing and TV viewing behaviour with MSK pain. The point prevalence of MSK pain was 25.5%. The longest category of game playing time (≥3 h) was significantly associated with MSK pain as compared with the shortest category (<1 h) (odds ratio, 1.39; 95% confidence interval, 1.12–1.73, p = 0.003). There was no significant association between TV viewing time and MSK pain. These results suggest that game playing time might be an associated factor for MSK pain among youth athletes. 相似文献
16.
Midori Kanazawa 《Public Library Quarterly》2018,37(2):209-221
ABSTRACTBoth Children’s services and Young Adult (YA) services have been recognized as essential in Japanese public libraries. This article reports on the present status of Children’s services and YA services in Japanese public libraries, based on the results of several investigations. These studies show that children’s services in Japanese public libraries already are generally popular. On the other hand, this article indicates that YA services in Japanese public libraries are gradually improving, due to the national recognition of the importance of YA library services. Examples of good practices in Children’s and YA services in Japanese public libraries are described and analyzed to identify the common themes that flow through these innovations. This article concludes with observations about the future involving library services for children and YAs, from the viewpoints of face-to-face traditional services and indirect services through their official websites. 相似文献
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This paper proposes a method to improve retrieval performance of the vector space model (VSM) in part by utilizing user-supplied information of those documents that are relevant to the query in question. In addition to the user's relevance feedback information, information such as original document similarities is incorporated into the retrieval model, which is built by using a sequence of linear transformations. High-dimensional and sparse vectors are then reduced by singular value decomposition (SVD) and transformed into a low-dimensional vector space, namely the space representing the latent semantic meanings of words. The method has been tested with two test collections, the Medline collection and the Cranfield collection. In order to train the model, multiple partitions are created for each collection. Improvement of average precision of the averages over all partitions, compared with the latent semantic indexing (LSI) model, are 20.57% (Medline) and 22.23% (Cranfield) for the two training data sets, and 0.47% (Medline) and 4.78% (Cranfield) for the test data, respectively. The proposed method provides an approach that makes it possible to preserve user-supplied relevance information for the long term in the system in order to use it later. 相似文献
19.
For people who live in the knowledge society which have rapidly been changing, learning in the widest sense becomes indispensable in all phases of working, living and playing. The construction of an environment, to meet the demands of people who need to acquire new knowledge and skills as the need arises, and enlighten each other regularly, is becoming very important. Thus, we hope to make the best use of the advantages of a rich e-learning environment which aims at ＂anytime, anywhere and anybody＂ learning, because participants in lifelong learning for the knowledge society demand to learn at the right place and right time, and with learning content, they can select themselves. However, in a general e-learning environment so far, because the situation is usual in which the instructor is absent and has the asynchronous access without an immediate communication with others, the participants tend to be solitude and it is difficult to maintain the learning motivation. Therefore, the creation of a new e-learning environment becomes extremely important in which various participants can learn and enlighten each other through an occasional and helpful interaction among them in appropriate learning communities in the network environment. In this paper, we present 5 points as basic requirements for the construction of an e-learning environment which can satisfy the various learning demands of the knowledge society, and discuss how to realize them. The key point here is the extension of the usual ＂strong＂ collaborative learning to effective ＂weak collaborative learning＂. In addition, the evolution of ＂symbiotic learning＂ for the knowledge society, that is, the necessity of ＂symbiotic e-learning environment based on occasional collaborative relationship＂ and its effective realization are discussed. 相似文献
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Christiane Perme Theresa Nalty Chris Winkelman Ricardo Kenji Nawa Faisal Masud 《Cardiopulmonary Physical Therapy Journal》2013,24(2):12-17