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111.
This study evaluates the current application of United States copyright law in music sampling cases and used the Danger Mouse's Grey Album as a case in point. The following research questions structured the investigation: Are the current applications of United States copyright law appropriate for digital sampling in an international intellectual property environment? Is the practice of digital sampling stealing or recycling? How might the American legislature change copyright law to more clearly guide musical artists on the use of digital sampling? The research includes a review of sampling and its history, international and American copyright history, and the applicable elements of the Copyright Act of 1976, as well as interviews with legal professionals and musicians. The research suggests that the Copyright Act of 1976 is not adequate to address the technology and practices of digital sampling musicians, and that Congress needs to act precisely to amend the law and meet international legal standards. 相似文献
112.
The authors analyzed data from the 2002 National Study of the Changing Workforce (N = 3,504) to investigate relationships among availability of formal organizational family support (family benefits and alternative schedules), job autonomy, informal organizational support (work-family culture, supervisor support, and coworker support), perceived control, and employee attitudes and well-being. Using hierarchical regression, the authors found that the availability of family benefits was associated with stress, life satisfaction, and turnover intentions, and the availability of alternative schedules was not related to any of the outcomes. Job autonomy and informal organizational support were associated with almost all the outcomes, including positive spillover. Perceived control mediated most of the relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
113.
Andrés Bruhn Joachim Weickert Christoph Schnörr 《International Journal of Computer Vision》2005,61(3):211-231
Differential methods belong to the most widely used techniques for optic flow computation in image sequences. They can be classified into local methods such as the Lucas–Kanade technique or Bigün's structure tensor method, and into global methods such as the Horn/Schunck approach and its extensions. Often local methods are more robust under noise, while global techniques yield dense flow fields. The goal of this paper is to contribute to a better understanding and the design of novel differential methods in four ways; (i) We juxtapose the role of smoothing/regularisation processes that are required in local and global differential methods for optic flow computation. (ii) This discussion motivates us to describe and evaluate a novel method that combines important advantages of local and global approaches: It yields dense flow fields that are robust against noise. (iii) Spatiotemporal and nonlinear extensions as well as multiresolution frameworks are presented for this hybrid method. (iv) We propose a simple confidence measure for optic flow methods that minimise energy functionals. It allows to sparsify a dense flow field gradually, depending on the reliability required for the resulting flow. Comparisons with experiments from the literature demonstrate the favourable performance of the proposed methods and the confidence measure. 相似文献
114.
Christian Feddern Joachim Weickert Bernhard Burgeth Martin Welk 《International Journal of Computer Vision》2006,69(1):93-107
Matrix-valued data sets arise in a number of applications including diffusion tensor magnetic resonance imaging (DT-MRI) and
physical measurements of anisotropic behaviour. Consequently, there arises the need to filter and segment such tensor fields.
In order to detect edge-like structures in tensor fields, we first generalise Di Zenzo’s concept of a structure tensor for
vector-valued images to tensor-valued data. This structure tensor allows us to extend scalar-valued mean curvature motion
and self-snakes to the tensor setting. We present both two-dimensional and three-dimensional formulations, and we prove that
these filters maintain positive semidefiniteness if the initial matrix data are positive semidefinite. We give an interpretation
of tensorial mean curvature motion as a process for which the corresponding curve evolution of each generalised level line
is the gradient descent of its total length. Moreover, we propose a geodesic active contour model for segmenting tensor fields
and interpret it as a minimiser of a suitable energy functional with a metric induced by the tensor image. Since tensorial
active contours incorporate information from all channels, they give a contour representation that is highly robust under
noise. Experiments on three-dimensional DT-MRI data and an indefinite tensor field from fluid dynamics show that the proposed
methods inherit the essential properties of their scalar-valued counterparts. 相似文献
115.
John Sheffield Thomas M. Antonsen Jr. Lee A. Berry Michael R. Brown Jill P. Dahlburg Ronald C. Davidson Martin Greenwald Chris C. Hegna William McCurdy David E. Newman Claudio Pellegrini Cynthia K. Phillips Douglass E. Post Marshall N. Rosenbluth Thomas C. Simonen James Van Dam 《Journal of Fusion Energy》2000,19(3-4):229-244
This Panel was set up by the Fusion Energy Sciences Advisory Committee (FESAC) at its November 2000 meeting for the purpose of addressing questions from the Department of Energy concerning the theory and computing/simulation program of the Office of Fusion Energy Sciences. Although the Panel primarily addressed programmatic questions, it acknowledges that the theory and computing in fusion energy sciences has a stellar record of research successes. (A recent FESAC report entitled Opportunities in the Fusion Energy Sciences Program listed a number of theory and computing research highlights.) Last year the National Research Council performed an assessment of the quality of the fusion energy sciences program—including theory and computing—and concluded that the quality of its research is on a par with that of other leading areas of contemporary physical science. 相似文献
116.
Daley Shannon E.; Hammen Constance; Davila Joanne; Burge Dorli 《Canadian Metallurgical Quarterly》1998,66(4):595
This study examined 2 models of the relationship between personality disorder symptomatology and depression, incorporating life stress as an intervening variable. In a community sample of late adolescent women, symptoms of Cluster B disorders predicted interpersonal chronic stress and self-generated episodic stress over 2 years, controlling for initial depression. Cluster A symptoms also predicted subsequent chronic interpersonal stress, over initial depression. Cluster C pathology did not predict subsequent stress. Personality disorder symptomatology was also associated with partner reported relationship dissatisfaction. Support was found for a mediation model whereby women with higher levels of initial personality disturbance in Clusters A and B generated excessive amounts of episodic stress and interpersonal chronic stress in the next 2 years, which, in turn, increased vulnerability for depressive symptoms. A moderation model, whereby the presence of greater personality disorder symptoms would increase the likelihood of depression in response to stress, was not supported. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
117.
QUE, QUerying the Expert system, is designed to provide a collaborative exploratory environment for a variety of types of users of expert systems. Explanation in intelligent systems has long been the subject of research from a number of different approaches, each of which has shown promise as well as problems. This paper describes how QUE, which is currently under development, approaches the problem of providing explanation by providing tools for both developers and users that enable explanation and user understanding of the underlying expert system's reasoning. 相似文献
118.
J Jordan JR Shannon BK Black SY Paranjape J Barwise D Robertson 《Canadian Metallurgical Quarterly》1998,32(4):699-704
We examined the gelatinolytic activity in human oral squamous-cell carcinoma tissues in order to evaluate the capability of intravasation and extravasation of cancer cells. By a microdissection-zymography, we demonstrated separately the gelatinolytic activities in cancer cell nests and stroma adjacent to the cancer cells. The gelatinolytic activities, such as pro-matrix metalloproteinase (MMP)9 and active-MMP2 in most of cancer cell nests were much higher than those of normal gingival epithelium. Moreover, the activities of active-MMP2 in cancer cell nests of metastatic cancers were significantly higher than those of non-metastatic cancers (p<0.05). These results suggest that active-MMP2 in cancer cells can be a predictive marker for metastasis formation in oral squamous-cell carcinoma patients. 相似文献
119.
Cynthia K. Whitney 《Journal of Manufacturing Systems》1985,4(2):157-167
Flexible manufacturing systems present a setting in which application of control concepts can be crucial. Today, some concepts are in place where needed, some are waiting to be applied, and some are yet to be created. This paper is a status report on FMS control technology, based on ongoing work at the The Charles Stark Draper Laboratory in the development of decision support systems for FMSs. 相似文献
120.
Relaxation of extrinsic and intrinsic stresses in germanium substrates with silicon films 总被引:1,自引:0,他引:1
Cynthia G. Madras Peter Y. Wong Ioannis N. Miaoulis Lee Goldman Ralph Korenstein 《Thin solid films》1998,320(2):260-263
Si films were deposited on Ge substrates at 400°C by two different Physical Vapor Deposition techniques: (A) ion beam sputtering and (B) magnetron sputtering. The intrinsic stresses in the as-deposited films were measured to be compressive and much greater in samples (A), about −1500 to −2000 MPa than in samples (B), about −300 to −500 MPa. The substrates were subsequently exposed to thermal treatments for varying times at 800°C. In the lower stressed (B) samples, the films had relaxed and reduced the overall curvature of the structure whereas in the high stresses (A) samples, an irreversible large increase in the substrate curvature was found to occur. This indicated that plastic deformation in the Ge substrates itself had occurred. 相似文献