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Seitaro Kumamoto Kenshiro Nakatake Souichiro Fukuyama Keiichiro Yasuda Yusuke Kitamura Masaaki Iwatsuki Hideo Baba Toshihiro Ihara Yoshitaka Nakanishi Yuta Nakashima 《Biomicrofluidics》2020,14(6)
To study an environmental or biological solution, it is essential to separate its constituents. In this study, a 3D-deformable dynamic microfilter was developed to selectively separate the target substance from a solution. This microfilter is a fine metallic nickel structure fabricated using photolithography and electroplating techniques. It is gold-coated across its entire surface with multiple slits of 10–20 μm in width. Its two-dimensional shape is deformed into a three-dimensional shape when used for fluid separation due to hydrodynamic forces. By adjusting the pressure applied to the microfilter, the size of the gap created by deformation can be changed. To effectively isolate the target substance, the relationship between the solution flow rate and the extent of microfilter deformation was investigated. The filtration experiments demonstrated the microfilter’s ability to isolate the target substance with elastic deformation without undergoing plastic deformation. Additionally, modification of the microfilter surface with nucleic acid aptamers resulted in the selective isolation of the target cell, which further demonstrates the potential application of microfilters in the isolation of specific components of heterogeneous solutions. 相似文献
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Hai-Tao Yu Adam Jatowt Roi Blanco Hideo Joho Joemon M. Jose Long Chen Fajie Yuan 《Information processing & management》2018,54(4):507-528
To cope with ambiguous and/or underspecified queries, search result diversification (SRD) is a key technique that has attracted a lot of attention. This paper focuses on implicit SRD, where the subtopics underlying a query are unknown. Many existing methods appeal to the greedy strategy for generating diversified results. A common practice is using a heuristic criterion for making the locally optimal choice at each round. As a result, it is difficult to know whether the failures are caused by the optimization criterion or the setting of parameters. Different from previous studies, we formulate implicit SRD as a process of selecting and ranking k exemplar documents through integer linear programming (ILP). The key idea is that: for a specific query, we expect to maximize the overall relevance of the k exemplar documents. Meanwhile, we wish to maximize the representativeness of the selected exemplar documents with respect to the non-selected documents. Intuitively, if the selected exemplar documents concisely represent the entire set of documents, the novelty and diversity will naturally arise. Moreover, we propose two approaches ILP4ID (Integer Linear Programming for Implicit SRD) and AP4ID (Affinity Propagation for Implicit SRD) for solving the proposed formulation of implicit SRD. In particular, ILP4ID appeals to the strategy of bound-and-branch and is able to obtain the optimal solution. AP4ID being an approximate method transforms the target problem as a maximum-a-posteriori inference problem, and the message passing algorithm is adopted to find the solution. Furthermore, we investigate the differences and connections between the proposed models and prior models by casting them as different variants of the cluster-based paradigm for implicit SRD. To validate the effectiveness and efficiency of the proposed approaches, we conduct a series of experiments on four benchmark TREC diversity collections. The experimental results demonstrate that: (1) The proposed methods, especially ILP4ID, can achieve substantially improved performance over the state-of-the-art unsupervised methods for implicit SRD. (2) The initial runs, the number of input documents, query types, the ways of computing document similarity, the pre-defined cluster number and the optimization algorithm significantly affect the performance of diversification models. Careful examinations of these factors are highly recommended in the development of implicit SRD methods. Based on the in-depth study of different types of methods for implicit SRD, we provide additional insight into the cluster-based paradigm for implicit SRD. In particular, how the methods relying on greedy strategies impact the performance of implicit SRD, and how a particular diversification model should be fine-tuned. 相似文献
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Tupeni L. Baba Barry J. Fraser 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1983,29(4):465-483
A sample of 834 seventh grade students in Fiji participated in an evaluation of the UNDP Social Science curriculum by responding to questionnaires measuring attitudes to or perceptions of three important curriculum process criteria (Interest, Ease and Adequacy of Time). The three major purposes of the evaluation were to provide formative information to guide curriculum revision, to provide summative information about the overall efficacy of the curriculum, and to explore the differential suitability of the curriculum for students varying in personal and environmental characteristics. Examination of means on individual questionnaire items led to the identification of certain curriculum activities requiring modification to improve their level of Interest, Ease, or Adequacy of Time. The finding that the mean score was relatively high for most questionnaire items suggested that the majority of activities in the curriculum were perceived by students as interesting and easy and having sufficient time for completion. Multiple regression analyses revealed that a block of personal variables and a block of environmental variables, but not a block of person-environment interactions, accounted for a significant amount of variance in the three process criteria. In particular, it was found that student attitudes to the curriculum varied systematically with certain personal variables (e.g., student general interest in social science, student ethnicity) and environmental variables (e.g., school location, teacher training).
Zusammenfassung Eine Stichprobe von 834 Schülern des siebten Schuljahres auf den Fidschi-Inseln, die an einer Auswertung des UNDP sozialwissenschaftlichen Curriculums teilnahmen, indem sie Fragebogen beantworteten, welche die Einstellungen oder Wahrnehmungen dreier wichtiger Curriculumentwicklungskriterien (Interesse, Schwierigkeitsgrad und Angemessenheit des Zeitansatzes) maßen. Die drei Hauptziele der Auswertung waren, Hinweise zur Gestaltung als Anleitung zur Curriculumsüberarbeitung zu geben, zusammenfassende Information über die Gesamtwirkung des Curriculums zu erteilen, und die unterschiedliche Eignung des Curriculums für Schüler zu untersuchen, die in persönlichen und umweltbedingten Merkmalen abweichen. Die Untersuchung der Werte der individuellen Fragebogenpunkte führte zur Identifikation bestimmter Curriculumaktivitäten, die Veränderungen erforderten, um das Interessenniveau, den Schwierigkeitsgrad oder die Angemessenheit des Zeitansatzes zu verbessern. Die Feststellung, daß die durchschnittliche Punktzahl für die meisten Fragebogenpunkte relativ hoch war, legte nahe, daß die Mehrzahl der Aktivitäten im Curriculum von den Schülern als interessant, leicht und als zeitausreichend empfunden wurde. Multiple Regressionsanalysen zeigten, daß ein Block von persönlichen Variablen und ein Block von Umweltvariablen, aber kein Block von Person-, Umwelt-Interaktionen, Rechenschaft ablegten über einen signifikanten Betrag von Varianz in den drei Entwicklungskriterien. Im besonderen stellte sich heraus, daß die Einstellungen von Schülern zum Curriculum sich systematisch veränderten mit bestimmten persönlichen Variablen (z.B. allgemeines Interesse der Schüler an Sozialwissenschaften, ethnische Zugehörigkeit der Schüler) und durch Umweltvariablen (z.B. Schulstandort, Lehrerausbildung).
Résumé Aux îles Fidgi, un échantillon de 834 élèves du 7ième degré a participé à une évaluation du curriculum des sciences sociales de l'UNDP en remplissant des questionnaires qui mesuraient leurs attitudes vis-à-vis de trois critères importants du processus curriculaire ainsi que leurs perceptions de ces critères (intérêt, facilité et convenance du temps alloué). Les trois principaux objectifs de l'évaluation consistaient à apporter une information formative pour guider la révision du curriculum, à donner ensuite une information globale sur l'ensemble de l'efficacité du curriculum et enfin à explorer la convenance différentielle du curriculum pour les étudiants qui présentent des caractéristiques personnelles différentes et dont l'environnement diffère. L'examen des données moyennes de certains points du questionnaire a conduit à l'identification de certaines activités du curriculum qui ont nécessité une modification pour améliorer leur niveau d'intérêt, de facilité et de convenance du temps alloué. Le fait que la moyenne était relativement élevée pour la plupart des points du questionnaire laissait supposer que la majorité des activités de ce curriculum étaient intéressantes, faciles pour les étudiants et réalisables dans le temps alloué. Plusieurs analyses régressives ont montré qu'un bloc de variables personnelles et un bloc de variables liées à l'environnement, mais non pas un bloc d'interactions entre personnes et environnement, étaient responsables d'une grande variation des trois critères du processus. Il s'est avéré en particulier que les attitudes des étudiants vis-à-vis du curriculum variaient systématiquement en fonction de certaines variables personnelles (intérêt général des étudiants pour les sciences sociales, l'origine des étudiants) et de variables liées à l'environnement (emplacement de l'école, formation des enseignants).相似文献
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The presentation of search results on the web has been dominated by the textual form of document representation. On the other hand, the document’s visual aspects such as the layout, colour scheme, or presence of images have been studied in a limited context with regard to their effectiveness of search result presentation. This article presents a comparative evaluation of textual and visual forms of document representation as additional components of document surrogates. A total of 24 people were recruited for our task-based user study. The experimental results suggest that an increased level of document representation available in the search results can facilitate users’ interaction with a search interface. The results also suggest that the two forms of additional representations are likely beneficial to users’ information searching process in different contexts. 相似文献
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利用最新的GRAIL月球重力数据和LRO地形数据,计算重力/地形导纳及其相关性。结果表明,最新的测月数据能够在球谐系数达到500阶的时候依然保持比较高的相关性,精度得到很大的提高。全月重力/地形导纳在50阶以下（波长大于~220 km）,之后迅速增加,维持在110 mgal/km附近。利用Gauss-Newton迭代法计算得到全月弹性平均厚度Te=11.7 km,表明很有可能月球地形在月球早期就已经形成。 相似文献
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Tippins Deborah J. Kemp Andy Ogura Yasushi Akiyama Mikio Ikeda Hideo Isozaki Tetsuo Ochiai Hiroshi Ohshika Kiyoyuki Takemura Shigekazu Bryan Lynn Keys Carolyn Padilla Michael Riley Joseph P. Thomson Norman 《Journal of Science Teacher Education》2000,11(3):189-206
Journal of Science Teacher Education - 相似文献
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Thiolene-based microfluidic devices have been coupled with surface plasmon resonance imaging (SPRI) to provide an integrated platform to study interfacial interactions in both aqueous and organic solutions. In this work, we develop a photolithographic method that interfaces commercially available thiolene resin to gold and glass substrates to generate microfluidic channels with excellent adhesion that leave the underlying sensor surface free from contamination and readily available for surface modification through self-assembly. These devices can sustain high flow rates and have excellent solvent compatibility even with several organic solvents. To demonstrate the versatility of these devices, we have conducted nanomolar detection of streptavidin-biotin interactions using in situ SPRI. 相似文献
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The purpose of this paper is to trace the history of JUAA and its relationship with the central government in the realm of university evaluation. The role of JUAA has changed considerably during the course of university development in the past half century. It has taken two major turns. Initially, JUAA emerged as a strong candidate for governing universities in 1947. However, during the 1950s until the mid‐1980s, the Japanese government set up centralised education policies causing JUAA's prospects to fade. Now, JUAA's role has become increasingly important, because it has focused itself as an agent for enhancing the quality of higher education. 相似文献