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71.
Reports an error in "What is in a word? No versus Yes differentially engage the lateral orbitofrontal cortex" by Nelly Alia-Klein, Rita Z. Goldstein, Dardo Tomasi, Lei Zhang, Stephanie Fagin-Jones, Frank Telang, Gene-Jack Wang, Joanna S. Fowler and Nora D. Volkow (Emotion, 2007[Aug], Vol 7[3], 649-659). The supplemental materials link should appear as follows: http://dx.doi.org/10.1037/1528-3542.7.3.649.supp. (The following abstract of the original article appeared in record 2007-11660-018.) The words "No" and "Yes" are involved in conditioning to prohibit or encourage behavior, respectively. The authors, therefore, hypothesized that these words would be attributed to endogenous valence, activating neuronal circuits involved with valence and emotional control. Functional MRI (fMRI) at 4 Tesla was used to record regional brain activity while participants were exposed to emphatic vocalizations of the words. Results showed that No and Yes were associated with opposite brain-behavior responses; while No was negatively valenced, produced slower response times, and evoked a negative signal in the right lateral orbitofrontal cortex (OFC), Yes was positively valenced, produced faster response times, and evoked a positive signal in a contiguous region of the OFC. Attribution of negative valence to No and trait anger control were associated with increased responsivity of the OFC to No. Inasmuch as sensitivity to the prohibitive command No develops during childhood through interaction with primary caregivers as the first social objects, our findings may implicate the lateral OFC in the neurobiology of emotion regulation and subsequent social development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
FAST     
We propose Frontier Allocation Synchronized by Token passing (FAST), a distributed algorithm for online terrain coverage using multiple mobile robots, ensuring mutually exclusive selection of frontier cells. Many existing approaches cover the terrain in an irregular fashion, without considering the usability of the already covered region. For instance, in the task of floor cleaning in an office building, these approaches do not guarantee the cleanliness of large unbroken areas until a majority of the task is complete. FAST on the other hand, incrementally traverses the terrain generating structured trajectories for each robot. Following a structured trajectory for coverage path planning is proven to be a very powerful approach in literature. This renders large portions of the terrain usable even before the completion of the coverage task. The novel map representation techniques used in FAST render it scalable to large terrains, without affecting the volume of communication among robots. Moreover, the distributed nature of FAST allows incorporation of fault-tolerance mechanisms. Empirical investigations on maps of varied complexities and sizes both in simulation and on an experimental test-bed demonstrate that the proposed algorithm performs better than some of the benchmark approaches in terms of coverage completion time and less redundant coverage.  相似文献   
73.
Fowler, M. L., Phase-Based Frequency Estimation: A Review, Digital Signal Processing12 (2002) 590–615This paper provides a review of efficient frequency estimation methods that use only the phases of the signal samples. Such methods continue to attract attention in various applications such as radar, electronic warfare, and next-generation communication systems. We present the details of the basic phase-based method, including its theoretical basis and its performance characterization, and provide an integrated presentation of its threshold behavior. In addition, we review several improvements, implementations, and extensions of the basic method and give some new results and viewpoints. In particular, the paper shows that Kay's method is equivalent to Tretter's method together with a simple phase unwrapping algorithm (thus, Kay's method does not really avoid phase unwrapping errors). We also show that a phase-based method for estimating chirp parameters has an advantage when applied to sinusoids: improved threshold behavior. We present a method that, unlike most of the other phase-based methods, can start processing the signal before knowing the number of samples.  相似文献   
74.
Fowler  M. 《Software, IEEE》2003,20(1):12-13
When I started programming computers, I began with fairly primitive languages, such as Fortran 4 and various early flavors of Basic. One of the first things you learn using such languages - indeed, even using more up-to-date languages - is which types your language supports. Being oriented toward number crunching, Fortran supported integer and real types, with the interesting rule that any variable whose name started with the letters I through N was an integer, and all other variables were floats. I'm glad that convention hasn't caught on, although Perl is close. Furthermore, using object-oriented languages, you can define your own types and in the best languages, they act just as well as built-in ones.  相似文献   
75.
As machines and programs have become more complex, the process of programming applications that can exploit the power of high-performance systems has become more difficult and correspondingly more labor-intensive. This has substantially widened the software gap—the discrepancy between the need for new software and the aggregate capacity of the workforce to produce it. This problem has been compounded by the slow growth of programming productivity, especially for high-performance programs, over the past two decades. One way to bridge this gap is to make it possible for end users to develop programs in high-level domain-specific programming systems. In the past, a major impediment to the acceptance of such systems has been the poor performance of the resulting applications. To address this problem, we are developing a new compiler-based infrastructure, called TeleGen, that will make it practical to construct efficient domain-specific high-level languages from annotated component libraries. We call these languages telescoping languages, because they can be nested within one another. For programs written in telescoping languages, high performance and reasonable compilation times can be achieved by exhaustively analyzing the component libraries in advance to produce a language processor that recognizes and optimizes library operations as primitives in the language. The key to making this strategy practical is to keep compile times low by generating a custom compiler with extensive built-in knowledge of the underlying libraries. The goal is to achieve compile times that are linearly proportional to the size of the program presented by the user, rather than to the aggregate size of that program plus the base libraries.  相似文献   
76.
The mathematical concept of the d-code and its associated contact graph give a model for sterically constrained addition patterns in fullerene derivatives C60Xm and C70Xm. In combination with simple electronic arguments, the stoichiometries, symmetries, and location of addends can be predicted, yielding a small number of candidates for further study. For example, sterically and optimal solutions C60Xm with pairwise separation of d bonds between addends are found at m(d) = 24(2), 12(3), 6(4,5), 2(6 to 9). The solution for C60X24 is unique, and the model selects 12 candidates for C60X12 from a starting set of 11661527060 possibilities.  相似文献   
77.
78.
Variant design for mechanical artifacts: A state-of-the-art survey   总被引:11,自引:0,他引:11  
Variant design refers, to the technique of adapting existing design specifications to satisfy new design goals and constraints. Specific support of variant design techniques in current computer aided design systems would help to realize a rapid response manufacturing environment. A survey of approaches supporting variant design is presented. Capabilities used in current commercial computer aided design systems are discussed along with approaches used in recent research efforts. Information standards applicable to variant design are also identified. Barriers to variant design in current systems are identified and ideas are presented for augmentation of current systems to support variant design.  相似文献   
79.
B Fowler  E Pang  I Mitchell 《Human factors》1992,34(1):115-120
Ten subjects breathed experimental mixtures of 20% and 35% nitrous oxide (N2O) balanced with oxygen and then aligned a pointer with a target using vision, kinesthesis, or combinations of these senses. In a prior session the subjects had been trained on the task with feedback while breathing N2O. The results showed that N2O did not influence variable error (VE), constant error, (CE), or absolute CE, but perceptual conditions influenced VE and absolute CE. These results suggest that the demonstration by Legge (1965) of changes in the variability and accuracy of matching on this task under N2O are indicative of changes in response bias and/or attention rather than perceptual sensitivity. It is argued that narcosis slows rather than distorts information processing. Slowing is accompanied by strategic changes that may be maladaptive. This suggests that, contrary to conventional wisdom, the safety and efficiency of divers exposed to narcosis could be improved with training.  相似文献   
80.
NURBS (non-uniform rational b-spline) modelling has become a ubiquitous tool within architectural design praxis. In this article I examine three projects that utilise NURBS modelling as a means for which a musical system's inherent spatiality is visualised. There are numerous precedents for which architectural form is a derivation of a musical system, or a musical system is proportionally informed by architectonic gesture. I propose in this article three NURBS modelling methodologies: for the spatial analysis of Karlheinz Stockhausen's sound projection geometries in Pole für 2; for a spatial realisation of John Cage's indeterminate work Variations III; and for the generation of a surface manifold informed by musically derived soundscape data from the Japanese garden Kyu Furukawa Teien. Rather than seeking to translate music into inhabitable architecture, or architectonic form into music, I highlight an approach that produces an interstitial territory between discourses on architecture and music analysis.  相似文献   
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