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51.
52.
Marvin C. McCallum John L. Campbell Joel B. Richman James L. Brown Emily Wiese 《International Journal of Speech Technology》2004,7(1):25-33
Speech Recognition is frequently cited as a potential remedy to distraction resulting from drivers' operation of in-vehicle devices. This position typically assumes that the introduction of speech recognition will result in reduced cognitive workload and improved driving performance. Past research neither fully supports nor fully discounts this assumption. However, it is difficult to compare many of these studies, due to differences in device operation tasks, the pacing of those tasks, speech recognition system performance, and system interface designs. In an effort to directly address the effect of voice recognition on driver distraction, the present authors developed a capability to manipulate the performance characteristics of a speech recognition system through a Wizard of Oz speech recognition system and installed this system in a simulated driving environment. The sensitivity of the simulated driving environment and speech recognition accuracy manipulation were evaluated in an initial study comparing driver cognitive workload and driving performance during self-paced simulated operation of a personal digital assistant (PDA) during no PDA use, manual control of the PDA, and speech control of the PDA. In the Speech PDA condition, speech recognition accuracy was varied between drivers. Analysis of drivers' emergency braking response times and rated cognitive workload revealed significantly lower cognitive demand and better performance in the No PDA condition when compared to the Manual PDA condition. The Speech PDA condition resulted in response times and rated cognitive workload levels that were between the No PDA and Manual PDA conditions, but not significantly different from either of these conditions. Further analysis of emergency braking performance revealed a non-significant trend towards better performance in conjunction with higher speech recognition accuracy levels. The potential for reducing driver distraction through the careful development and evaluation of speech recognition systems is discussed. 相似文献
53.
Antoine Tran Tan Joel Falcou Daniel Etiemble Hartmut Kaiser 《International journal of parallel programming》2016,44(3):449-465
Providing high level tools for parallel programming while sustaining a high level of performance has been a challenge that techniques like Domain Specific Embedded Languages try to solve. In previous works, we investigated the design of such a DSEL—NT\(^2\)—providing a Matlab -like syntax for parallel numerical computations inside a C++ library. In this paper, we show how NT\(^2\!\) has been redesigned for shared memory systems in an extensible and portable way. The new NT\(^2\!\) design relies on a tiered Parallel Skeleton system built using asynchronous task management and automatic compile-time taskification of user level code. We describe how this system can operate various shared memory runtimes and evaluate the design by using two benchmarks implementing linear algebra algorithms. 相似文献
54.
Three shear turbulence resuspension mesocosms (STORM tanks) were used to examine the release of polychlorinated biphenyls (PCBs) from resuspended Hudson River sediment. Twenty-two percent of the resuspended PCBs desorbed after 2 h, and 35% +/- 8% of PCBs were in the dissolved phase after apparent steady state was reached in 2 days. After the first resuspension event, the solids were allowed to settle and the quiescent time was varied to determine whether the labile pool of PCBs is recharged during sediment consolidation. The steady-state log Koc values for the third subsequent resuspension were higher than for the first event due to lower dissolved PCB concentrations; the particulate PCB concentrations were constant between events. With 1 day of consolidation between resuspension events, the dissolved concentration of all congeners decreased an average of 8% +/- 5% between subsequent resuspension events. With 4 days between events, only the dissolved pentachlorinated PCBs decreased significantly (p = 0.002), suggesting that the easily desorbable PCBs recharge when there is sufficient time between resuspension events. 相似文献
55.
Kay MK Cartwright EJ Maceachern D McCullough J Barzilay E Mintz E Duchin JS Macdonald K Turnsek M Tarr C Talkington D Newton A Marfin AA 《Journal of food protection》2012,75(4):762-764
We report a cluster of severe diarrheal disease caused by Vibrio mimicus infection among four persons who had consumed leftover crayfish the day after a private crayfish boil. Gastrointestinal illness caused by Vibrio mimicus has not been reported previously in Washington State. Three cases were laboratory confirmed by stool culture; using PCR, isolates were found to have ctx genes that encode cholera toxin (CT). Two of the cases were hospitalized under intensive care with a cholera-like illness. The illnesses were most likely caused by cross-contamination of cooked crayfish with uncooked crayfish; however, V. mimicus was not isolated nor were CT genes detected by PCR in leftover samples of frozen crayfish. Clinicians should be aware that V. mimicus can produce CT and that V. mimicus infection can cause severe illness. 相似文献
56.
Joel G. Manathara P. B. Sujit Randal W. Beard 《Journal of Intelligent and Robotic Systems》2011,62(1):125-158
Unmanned aerial vehicles (UAVs) have the potential to carry resources in support of search and prosecute operations. Often
to completely prosecute a target, UAVs may have to simultaneously attack the target with various resources with different
capacities. However, the UAVs are capable of carrying only limited resources in small quantities, hence, a group of UAVs (coalition) needs to be assigned that satisfies the target resource requirement. The assigned coalition must be such that it minimizes
the target prosecution delay and the size of the coalition. The problem of forming coalitions is computationally intensive
due to the combinatorial nature of the problem, but for real-time applications computationally cheap solutions are required.
In this paper, we propose decentralized sub-optimal (polynomial time) and decentralized optimal coalition formation algorithms
that generate coalitions for a single target with low computational complexity. We compare the performance of the proposed
algorithms to that of a global optimal solution for which we need to solve a centralized combinatorial optimization problem.
This problem is computationally intensive because the solution has to (a) provide a coalition for each target, (b) design
a sequence in which targets need to be prosecuted, and (c) take into account reduction of UAV resources with usage. To solve
this problem we use the Particle Swarm Optimization (PSO) technique. Through simulations, we study the performance of the proposed algorithms in terms of mission performance,
complexity of the algorithms and the time taken to form the coalition. The simulation results show that the solution provided
by the proposed algorithms is close to the global optimal solution and requires far less computational resources. 相似文献
57.
Adsorption of sulfonamide antimicrobial agents to clay minerals 总被引:9,自引:0,他引:9
Adsorption of three sulfonamide antimicrobials to clay minerals was investigated as a function of pH, ionic strength, and type of exchangeable cation. Sulfonamide antimicrobial adsorption exhibited pronounced pH dependence consistent with sorbate speciation and clay properties. Sulfonamide antimicrobials did not intercalate into montmorillonite, and surface charge density influenced sorption by determining adsorption domain size. Adsorption edge data were best fit to a model including terms for the cationic and uncharged species. Adsorption of uncharged sulfamethazine to montmorillonite was relatively insensitive to pH, ionic strength, and type of exchangeable cation, while that to kaolinite was highly sensitive to ionic strength. Adsorption of cationic sulfamethazine to montmorillonite exceeded that of the neutral species by 1-2 orders of magnitude, but was unimportant for kaolinite atthe pH values examined. Cation exchange appeared to contribute to sorption of cationic sulfonamide species to montmorillonite. Anionic sulfamethazine adsorption was negligible. The nature of the sulfonamide R group influenced the degree of adsorption of cationic and neutral species. Our results highlight the importance of considering sulfonamide speciation and clay surface charge density in predicting the transport of these antimicrobials. 相似文献
58.
The relationships between the alcohol yield obtainable from different malts and some readily measurable parameters have been investigated. Gel filtration studies clearly show that melanoidin-type condensation products, which were previously suggested as a cause of low fermentability, are not produced in significant amounts in highly modified malts. These studies also show important details relating to the hydrolysis of dextrins in distillers' worts and washes. Measurement of the limit dextrinase activity of a range of distillers' malts has indicated that this enzyme is not a limiting factor in determining wort fermentability and its concentration does not correlate with the overall spirit yield. There may be a relationship between the whole amylase complex, as expressed by the diastatic power and wort fermentability. From a study of the reducing sugar contents of worts, it was confirmed that the major factor controlling fermentable extract in malt is the relative amounts of starch-derived sugars in the wort. It now appears possible to determine the fermentability of distilling wort by the standard extract and the reducing power of the wort obtained by the standard I.O.B. extraction. 相似文献
59.
60.
Joel. L. Plawsky William N. Gill Ravi S. Achanta 《Journal of Materials Science: Materials in Electronics》2012,23(1):48-55
Copper solubility in low-k dielectrics has been shown to be a major factor in decreasing the useful lifetime of an interconnect.
A number of groups have shown experimentally that increased surface oxygen concentration, increased moisture content in the
dielectric, and an increase in interfacial copper concentration from chemical–mechanical polishing all contribute to accelerated
failure. Here, we assumed that all these processes led to an increase in the solubility of metal at the SiO2/metal. We systematically varied the value of the interfacial solubility, Ce over a wide range and showed that the solubility strongly affects the distribution of copper and the local electric field
within the dielectric. This changes the mechanism by which failure occurs from one where copper must penetrate all the way
through the dielectric to one where copper penetration is limited to a thin layer near the surface. The solubility levels
required to alter the failure mechanism, 1026–1027 atoms/m3, are within the realm of possibility and have been reported in the context of fabricating Cu-SiO2 resistive switching elements for memory applications. 相似文献