1,721,231 research outputs found
Design of MEMS resonator array for minimization of mode localization factor subject to random fabrication error
No full text학위논문(석사) - 한국과학기술원 : 기계공학전공, 2005.2, [ xiii, 77 p. ]반복 구조물 형태를 이루는 MEMS 공진기의 제조 공정에서 발생하는 랜덤 오차에 의한 모드 변화 현상을 최소화 하기 위한 최적 설계를 하였다. 우선 반복 구조물에서 가장 흔하게 발생하는 문제인 모드 편재현상을 MAC, 섭동법을 이용하여 모드 변화량으로 정의하였다. 발생한 랜덤 오차에 대한 모드 편재계수의 기대치를 최소화하는 최적 형상을 구하고 이를 공진기의 초기 설계시에 적용하여 공진기의 강건성을 증명하였다.한국과학기술원 : 기계공학전공
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Statistical Modeling of Inter-Frame Prediction Error and Its Adaptive Transform
No full textMost video coding standards use the discrete cosine transform, known to be near optimal for original images, to transform prediction errors. Since the statistical characteristics of prediction errors are quite different from those of original images, a more suitable transform for prediction errors has to be devised. In this letter, we introduce a novel statistical model for inter-frame prediction error and propose an adaptive transform based on the model. In addition, in order to reduce the computation time, a fast and efficient algorithm is developed. Experiments on well-known image sequences confirm that our proposed transform can improve the performance of transform coding significantly
Self-Regulation of Infrared Using a Liquid Crystal Mixture Doped with Push-Pull Azobenzene for Energy-Saving Smart Windows
No full textA self-regulating liquid crystal (LC) smart window whose reflectance changes with ambient conditions is demonstrated. Thermally or optically induced switching between the transparent state and a near-infrared (NIR) reflective state can be used for energy-saving windows. Reflection of NIR can reduce the energy used for cooling, while remaining transparent to visible light. By changing the initial alignment of LCs, the window can be switched between hazy-opaque and IR-reflective states to be used for privacy windows.11Nsciescopu
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
A simulation of diffractive liquid crystal smart window for privacy application
No full textUsing a single substrate, we demonstrate a simple two-dimensional (2-D) phase grating cell with an octothorp electrode. Owing to the large spatial phase difference in any direction, the proposed grating cell has a high haze value in the opaque state (76.7%); Moreover, it has the advantages of a one-dimensional (1-D) phase grating cell, such as high fabricability, fast response time, and low operating voltage. Furthermore, the proposed grating cell has a faster response time than the 2-D grating cell (comparable to a 1-D grating cell). All the electro-optic parameters have been calculated using a commercial modeling tool. Consequently, we expect our proposed grating cell to find applications in virtual reality (VR)/augmented reality (AR) systems or window displays with fast response times
Endurable Transient Inconsistency in Byte-Addressable Persistent B+-Tree
No full textWith the emergence of byte-addressable persistent memory (PM), a cache line, instead of a page, is expected to be the unit of data transfer between volatile and nonvolatile devices, but the failure-atomicity of write operations is guaranteed in the granularity of 8 bytes rather than cache lines. This granularity mismatch problem has generated interest in redesigning block-based data structures such as B+-trees. However, various methods of modifying B+-trees for PM degrade the efficiency of B+trees, and attempts have been made to use in-memory data structures for PM. In this study, we develop Failure-Atomic ShifT (FAST) and Failure-Atomic In-place Rebalance (FAIR) algorithms to resolve the granularity mismatch problem. Every 8-byte store instruction used in the FAST and FAIR algorithms transforms a B+-tree into another consistent state or a transient inconsistent state that read operations can tolerate. By making read operations tolerate transient inconsistency, we can avoid expensive copy-on-write, logging, and even the necessity of read latches so that read transactions can be non-blocking. Our experimental results show that legacy B+-trees with FAST and FAIR schemes outperform the state-of-the-art persistent indexing structures by a large margin
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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