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81.
User authentication is one of the fundamental procedures to ensure secure communications over an insecure public network channel. Especially, due to tamper-resistance and convenience in managing a password file, various user authentication schemes using smart cards have been proposed. A smart card however far from ubiquitous because of the high cost of a smart card and the infrastructure requirements. In this paper, we study secure user authentication using only a common storage device such as a universal serial bus (USB) memory, instead of using smart cards. We first show that the existing schemes using smart cards cannot be immediately converted into schemes using a common storage device. We then propose a practical and secure user authentication scheme, capable of supporting the use of the common storage device, which retains all the advantages of schemes using smart cards. 相似文献
82.
83.
To understand the user experience in social media or to facilitate the design of human-centric services by social media, users’ opinions about specific entities in text messages should be captured. A fine-grained named entity recognizer (NER) is an essential module for identifying opinion targets in text messages, and a named-entity (NE) dictionary is a major resource that affects the performance of an NER. However, it is not easy to construct an NE dictionary manually, because human annotation is time-consuming and labor-intensive. To reduce construction time and labor, we propose a semi-automatic system to construct an NE dictionary from the free online resource, Wikipedia. The proposed system constructs a pseudo-document for each Wikipedia NE by using an active-learning technique. It then classifies Wikipedia entries into NE classes based on similarities between the entries and pseudo-documents located in a vector space. In experiments, the proposed system classified 92.3 % of Wikipedia entries into 29 NE classes. It showed a high performance, with a macro-averaging F1-measure of 0.872 and micro-averaging F1-measure of 0.935. 相似文献
84.
Lee Jae-Gu Choi Kyung-Chan Yeon Seung-Ho Kim Jeong Won Ko Young-Woong 《Multimedia Tools and Applications》2017,76(23):25477-25494
Multimedia Tools and Applications - In digital pathology, image similarity algorithms are used to find cancer in tissue cells from medical images. However, it is very difficult to apply image... 相似文献
85.
Stephen G. McGill Seung‐Joon Yi Hak Yi Min Sung Ahn Sanghyun Cho Kevin Liu Daniel Sun Bhoram Lee Heejin Jeong Jinwook Huh Dennis Hong Daniel D. Lee 《野外机器人技术杂志》2017,34(4):775-801
This paper describes Team THOR's approach to human‐in‐the‐loop disaster response robotics for the 2015 DARPA Robotics Challenge (DRC) Finals. Under the duress of unpredictable networking and terrain, fluid operator interactions and dynamic disturbance rejection become major concerns for effective teleoperation. We present a humanoid robot designed to effectively traverse a disaster environment while allowing for a wide range of manipulation abilities. To complement the robot hardware, a hierarchical software foundation implements network strategies that provide real‐time feedback to an operator under restricted bandwidth using layered user interfaces. Our strategy for humanoid locomotion includes a backward‐facing knee configuration paired with specialized toe and heel lifting strategies that allow the robot to traverse difficult surfaces while rejecting external perturbations. With an upper body planner that encodes operator preferences, predictable motion plans are executed in unforeseen circumstances. These plans are critical for manipulation in unknown environments. Our approach was validated during the DRC Finals competition, where Team THOR scored three points in 18 min of operation time, and the results are presented along with an analysis of each task. 相似文献
86.
Young-Seon Jeong Author Vitae Author Vitae Olufemi A. Omitaomu Author Vitae 《Pattern recognition》2011,44(9):2231-2240
Dynamic time warping (DTW), which finds the minimum path by providing non-linear alignments between two time series, has been widely used as a distance measure for time series classification and clustering. However, DTW does not account for the relative importance regarding the phase difference between a reference point and a testing point. This may lead to misclassification especially in applications where the shape similarity between two sequences is a major consideration for an accurate recognition. Therefore, we propose a novel distance measure, called a weighted DTW (WDTW), which is a penalty-based DTW. Our approach penalizes points with higher phase difference between a reference point and a testing point in order to prevent minimum distance distortion caused by outliers. The rationale underlying the proposed distance measure is demonstrated with some illustrative examples. A new weight function, called the modified logistic weight function (MLWF), is also proposed to systematically assign weights as a function of the phase difference between a reference point and a testing point. By applying different weights to adjacent points, the proposed algorithm can enhance the detection of similarity between two time series. We show that some popular distance measures such as DTW and Euclidean distance are special cases of our proposed WDTW measure. We extend the proposed idea to other variants of DTW such as derivative dynamic time warping (DDTW) and propose the weighted version of DDTW. We have compared the performances of our proposed procedures with other popular approaches using public data sets available through the UCR Time Series Data Mining Archive for both time series classification and clustering problems. The experimental results indicate that the proposed approaches can achieve improved accuracy for time series classification and clustering problems. 相似文献
87.
Jeong Eun Min Matthew D. WhitesideFiona S.L. Brinkman Brad McNeneyJinko Graham 《Computational statistics & data analysis》2011,55(1):935-943
Orthologs are genes in different species that have diverged from a common ancestral gene after speciation. In contrast, paralogs are genes that have diverged after a gene duplication event. For many comparative analyses, it is of interest to identify orthologs with similar functions. Such orthologs tend to support species divergence (ssd-orthologs) in the sense that they have diverged only due to speciation, to the same relative degree as their species. However, due to incomplete sequencing or gene loss in a species, predicted orthologs can sometimes be paralogs or other non-ssd-orthologs. To increase the specificity of ssd-ortholog prediction, Fulton et al. [Fulton, D., Li, Y., Laird, M., Horsman, B., Roche, F., Brinkman, F., 2006. Improving the specificity of high-throughput ortholog prediction. BMC Bioinformatics 7 (1), 270] developed Ortholuge, a bioinformatics tool that identifies predicted orthologs with atypical genetic divergence. However, when the initial list of putative orthologs contains a non-negligible number of non-ssd-orthologs, the cut-off values that Ortholuge generates for orthology classification are difficult to interpret and can be too high, leading to decreased specificity of ssd-ortholog prediction. Therefore, we propose a complementary statistical approach to determining cut-off values. A benefit of the proposed approach is that it gives the user an estimated conditional probability that a predicted ortholog pair is unusually diverged. This enables the interpretation and selection of cut-off values based on a direct measure of the relative composition of ssd-orthologs versus non-ssd-orthologs. In a simulation comparison of the two approaches, we find that the statistical approach provides more stable cut-off values and improves the specificity of ssd-ortholog prediction for low-quality data sets of predicted orthologs. 相似文献
88.
Chi‐Woo Kim Chang‐Oh Jeong Jean‐Ho Song Hyung‐Guel Kim 《Journal of the Society for Information Display》2001,9(3):139-143
Abstract— TFT‐LCD panels for notebook‐PC applications requires a thin and light form factor, low power consumption, and good display quality, whereas the desktop monitor has different requirements such as large panel size, wide viewing angle, high resolution, brightness, etc. However, for the fifth‐generation of mass production, current panel technologies have to improve in order to cope with these requirements. In this article, various approaches to the manufacturing technologies of next‐generation TFT‐LCDs are discussed. 相似文献
89.
A feature relies on three dimensions (space, theme, and time) for its representation. Even though spatiotemporal models have
been proposed, they have principally focused on the spatial changes of a feature. In this paper, a feature-based temporal
model is proposed to represent the changes of both space and theme independently. The proposed model modifies the ISO’s temporal
schema and adds new explicit temporal relationship structure that stores temporal topological relationship with the ISO’s
temporal primitives of a feature in order to keep track feature history. The explicit temporal relationship can enhance query
performance on feature history by removing topological comparison during query process. Further, a prototype system has been
developed to test a proposed feature-based temporal model by querying land parcel history in Athens, Georgia. The result of
temporal query on individual feature history shows the efficiency of the explicit temporal relationship structure.
相似文献
E. Lynn UseryEmail: |
90.
A sparser but more efficient connection rule (called a bond-cutoff method) for a simplified alpha-carbon coarse-grained elastic network model is presented. One of conventional connection rules for elastic network models is the distance-cutoff method, where virtual springs connect an alpha-carbon with all neighbor alpha-carbons within predefined distance-cutoff value. However, though the maximum interaction distance between alpha-carbons is reported as 7 angstroms, this cutoff value can make the elastic network unstable in many cases of protein structures. Thus, a larger cutoff value (>11 angstroms) is often used to establish a stable elastic network model in previous researches. To overcome this problem, a connection rule for backbone model is proposed, which satisfies the minimum condition to stabilize an elastic network. Based on the backbone connections, each type of chemical interactions is considered and added to the elastic network model: disulfide bonds, hydrogen bonds, and salt-bridges. In addition, the van der Waals forces between alpha-carbons are modeled by using the distance-cutoff method. With the proposed connection rule, one can make an elastic network model with less than 7 angstroms distance cutoff, which can reveal protein flexibility more sharply. Moreover, the normal modes from the new elastic network model can reflect conformational changes of a given protein better than ones by the distance-cutoff method. This method can save the computational cost when calculating normal modes of a given protein structure, because it can reduce the total number of connections. As a validation, six example proteins are tested. Computational times and the overlap values between the conformational change and infinitesimal motion calculated by normal mode analysis are presented. Those animations are also available at UMass Morph Server (http://biomechanics.ecs.umass.edu/umms.html). 相似文献