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81.
Eighteen new counselor educators shared in‐depth reports of their efforts to establish an early record of scholarly productivity, critical to their success in academe. Analyses of their experiences using consensual qualitative research methods revealed components of both highly positive and highly discouraging program environments and their impact on participants’ research goals.  相似文献   
82.
The aim of this study was to validate a wearable inertial measurement unit (IMU), containing a 3D accelerometer and gyroscope, for the estimation of countermovement jump height. The absolute vertical acceleration of the IMU positioned on the back of the participant at L5 level, compensated for trunk rotations, was used to obtain jump height by applying the equation of free-fall to the motion of the IMU. The methodology was tested on 28 participants performing five countermovement jumps each. A reference value for this quantity was obtained using stereophotogrammetry (35.4 cm, s = 4.9). Jump height scores obtained using the proposed methodology (35.9 cm, s = 5.5) presented no significant difference with respect to stereophotogrammetry (P = 0.61). A low bias of 0.6 cm confirmed the accuracy of the estimate, which also showed a high (r = 0.87) and significant (P < 0.0001) correlation with reference values. Furthermore, without compensating accelerations for trunk rotation, jump height was largely underestimated (P < 0.0001) (bias: -12.7 cm) and poorly associated (r = 0.31) with stereophotogrammetry. The results of this study show that the estimation of jump height using inertial sensors leads to accurate results when the measured accelerations are corrected for trunk rotations.  相似文献   
83.
Product reviews have become an important resource for customers before they make purchase decisions. However, the abundance of reviews makes it difficult for customers to digest them and make informed choices. In our study, we aim to help customers who want to quickly capture the main idea of a lengthy product review before they read the details. In contrast with existing work on review analysis and document summarization, we aim to retrieve a set of real-world user questions to summarize a review. In this way, users would know what questions a given review can address and they may further read the review only if they have similar questions about the product. Specifically, we design a two-stage approach which consists of question selection and question diversification. For question selection phase, we first employ probabilistic retrieval models to locate candidate questions that are relevant to a given review. A Recurrent Neural Network Encoder–Decoder is utilized to measure the “answerability” of questions to a review. We then design a set function to re-rank the questions with the goal of rewarding diversity in the final question set. The set function satisfies submodularity and monotonicity, which results in an efficient greedy algorithm of submodular optimization. Evaluation on product reviews from two categories shows that the proposed approach is effective for discovering meaningful questions that are representative of individual reviews.  相似文献   
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86.
In the cultural heritage area, it is of fundamental importance to characterize and classify the conservation state of the materials constituting ancient monuments, in order to study and monitor their decay. Generally, the decay diagnosis is provided by “naked eye” analysis done by expert scientists “walking around” the artifact and recording the conservation state of each individual element they observe. In this paper, a color image segmentation approach, based on histogram threshold and edge detection techniques is presented, to extract degradation regions, characterized by holes or cavities, from color images of stone-materials. The goal is to provide an aid to the decay diagnosis by segmenting degraded regions from color images, computing quantitative data, such as the area and perimeter of the extracted zones, and processing qualitative information, such as various levels of depth detected into the same zones. Since color is a powerful tool in the distinction between objects, a segmentation technique based on color, instead of intensity only, has been used to provide a clearer discrimination between regions. The study case concerns the impressive remains of the Roman Theatre in the city of Aosta (Italy). In particular, we have processed and analyzed some color images of the theatre puddingstones, acquired by a camera.  相似文献   
87.
This study examined the links among adolescents' representations of their relationships with parents, friends, and romantic partners. Sixty-eight adolescents were interviewed three times to assess their working models for each of these types of relationships. Working models of friendships were related to working models of relationships with parents and romantic partners. Working models of relationships with parents and romantic partners were inconsistently related. A similar pattern of results was obtained for self-report measures of relational styles for the three types of relationships. Perceived experiences were also related. Specifically, support in relationships with parents tended to be related to support in romantic relationships and friendships, but the latter two were unrelated. On the other hand, self and other controlling behaviors in friendships were related to corresponding behaviors in romantic relationships. Negative interactions in the three types of relationships also tended to be related. Taken together, the findings indicate that the representations of the three types of relationships are distinct, yet related. Discussion focuses on the nature of the links among the three.  相似文献   
88.
This study examined how children's literacy interests related to parent literacy‐promoting practices across time. Using a sample of 909 preschool‐age children and the newly developed Child Activities Preference Checklist, literacy interest appeared to be a complex construct, not easily captured by a single measure. In a subsample of 230 children with longitudinal data, parent literacy practices and child literacy interests related concurrently and across time. Parent literacy practices were more stable than child literacy interests, with children's literacy interest continuing to develop over the preschool year. Parent practices of exposing children to literacy and teaching them literacy concepts appeared to be distinct constructs. Exposure to literacy was especially important in the growth of literacy interests and the hypothesis that exposure has a negative effect on children with little initial interest was not fully supported.  相似文献   
89.
Product cycles have long been used in software development, but libraries can also benefit from a structured product life cycle to help manage technology development and acquisition. This article outlines a proposed product cycle for library technology management with information on implementing each step of the cycle. It will also include information for librarians assessing the success of structured technology management.  相似文献   
90.
Photography     
Alexander Gardner, Gardner's Photographic Sketch Book of the Civil War (original edition 1866, reissued in 1959, $4.50, 224 pp.)

Ray Meredith, Mr. Lincoln's Cameraman: Mathew B. Brady (original edition 1946, reissued in slightly revised form in 1974, $6.95, 368 pp.)

Mary Black, Old New York in Early Photographs: 1853-1901 (new publication in 1973 (not a reprint), $6.00, 228 pp.)

Berenice Abbott, New York in the Thirties (original edition 1939, reissued 1973, $3.50, 100 pp.)

William Welling's Collector's Guide to Nineteenth Century Photographs (New York: Macmillan, 1976---$15.95/7.95)

Weston J. Naef and James N. Wood's Era of Exploration: The Rise of Landscape Photography in the American West: 1860---1885 (Boston: New York Graphic Society, 1975---S25.00)

James L. Lager's Leica Illustrated Guide: 1925-1975 (Dobbs Ferry, N.Y.: Morgan and Morgan, Inc., 1975---$7.95, paper)

Mark Jacobs and Ken Kokrda's Photography in Focus (Skokie, Ill.: National Textbook Co., 1975---price not given, paper; with a "Curriculum Guide for Photography" instructor's manual available as well)

Claus-Peter Sdhmid's Photography for Artists and Craftsmen (New York: Van Nostrand Reinhold, 1975---$9.95)  相似文献   
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