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Many media processing applications create a load that varies significantly over time. Hence, if such an application is assigned a lower processing-time budget than needed in its worst-case load situation, deadline misses are likely to occur. This problem can be dealt with by designing media processing applications in a scalable fashion. A scalable media processing application can run in multiple qualities, leading to correspondingly different resource demands. The problem we consider is to find an accompanying quality control strategy, which minimizes both the number of deadline misses and the number of quality changes, while maximizing the quality of processing. We present an initial approach to the above problem by modeling it as a Markov decision process (MDP). Our model is based on measuring relative progress at milestones. Solving the MDP results in a quality control strategy that can be applied during runtime with only little overhead. We evaluate our approach by means of a practical example, which concerns a scalable MPEG-2 decoder. 相似文献
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Is there a direct relationship between oral astringency and human salivary protein binding? 总被引:1,自引:0,他引:1
For decades, it is believed that astringency is due to the polyphenol-induced complexation of proline-rich salivary proteins
in the oral cavity. In order to compare for the first time the human sensory threshold concentrations and the salivary protein
binding activity of a series of astringent stimuli, human saliva protein was incubated for 5 min at 37 °C in the presence
of astringent food-derived compounds and, after micro-centrifugation, the amount of the target molecules in the supernatant
was quantitatively determined by HPLC-UV/Vis. Significant protein binding was observed for (−)-epigallocatechin-3-gallate,
(−)-gallocatechin-3-gallate, (+)-gallocatechin, and (−)-catechin-3-gallate, all of which containing at least one galloyl moiety
in the molecule and exhibiting rather high sensory thresholds of more than 200 μmol/L. In comparison, (+)-catechin and procyanidin
B2, both lacking in any galloyl function, showed only comparatively low binding activity and, most interestingly, quercetin-3-O-α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside and 3-carboxymethyl-indole-1-N-β-d-glucopyranoside did not show any protein binding at all, although the later N- and O-glycosides exhibited extraordinarily low sensory threshold concentrations of less than 0.001 and 0.0003 μmol/L, respectively.
The data give some first evidence that the quantity of the non-bound, “free” astringent stimulus in the saliva liquid might
be more closely related to the sensory perception of astringency than the amount complexed or precipitated by proteins. It
is therefore questionable as to whether oral perception of astringency is related to the complexation and/or precipitation
of salivary proteins. 相似文献
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Herzog K. Schulte E. Atmanand M. A. Schwarz W. 《Automation Science and Engineering, IEEE Transactions on》2007,4(2):282-286
Tracked vehicles capable of locomotion in the deep sea are used for manganese nodule mining. This requires specific technical solutions in various respects. Locomotion in the soft sea bed is one of them. For the Crawler to safely maneuver, an automatic drive mode with slip control of the driving tracks is essential. Based on experimental studies at IKS, University of Siegen, slip control for the NIOT-IKS mining machine has been developed and implemented. The experimental setup for the development of the slip control along with the logic of the automatic driving mode is described. The system is critically discussed and the test results and future work are briefly outlined. Note to Practitioners-The work is carried out as part of the polymetallic nodule mining program of the Government of India. The technique of slip control is a specific requirement for a tracked vehicle used in the deep sea. Slip is common in many vehicles-tracked and otherwise. Examples are steam engines in the early days and ordinary cars while negotiating slush or snow/ice and dozers working in soft soil. While these are manually controlled by drivers who have firsthand knowledge of the environmental conditions, in the case of a mining machine in deep sea, it has to be completely automatic and, hence, is challenging. The knowledge generated in this work could be effectively used by practitioners in other related areas of automobile engineering for updating their expertise. Also, similar techniques may be used for maneuvering vehicles sent to other planets 相似文献
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Assessments of sewer performance are usually based on a single computation of CSO (combined sewer overflow) volumes using a time series of rainfall as system loads. A shortcoming of this method is that uncertainties in knowledge of sewer system dimensions are not taken into account. Moreover, sewer models are rarely calibrated. This paper presents the impacts of database errors and model calibration on return periods of calculated CSO volumes. The impact of uncertainties is illustrated with two examples. Variability of calculated CSO volumes is estimated using Monte Carlo simulations. The results show that calculated CSO volumes vary considerably due to database errors, especially uncertain dimensions of the catchment area. Furthermore, event-based calibration of a sewer model does not result in more reliable predictions because the calibrated parameters have low portability. However, it enables removal of database errors harmonising model predictions and 'reality'. 相似文献
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OBJECTIVE: To evaluate the efficacy of terazosin, an alpha-blocker, for the treatment of idiopathic oligozoospermia. PATIENTS AND METHODS: Thirty couples with infertility whose only detectable abnormality was male idiopathic subfertility entered the study. The diagnosis of idiopathic subfertility in all males studied, aged 26 to 38 years (mean 28.2 years), was confirmed after exclusion of any iatrogenic, systemic, congenital, infectious, autoimmune or endocrinological cause. In order to start with a baseline value before the study, at least three semen samples were evaluated in accordance with the WHO recommendation. Before initiation of treatment, blood samples were drawn for measurement of FSH, LH, testosterone, prolactin, dihydrotestosterone, and estradiol. Fifteen randomly selected patients (Group A) received 2 mg/d of alpha-blocker (terazosin), while another 15 (Group B) were administered an identically packed placebo tablet. Both groups received therapy for 6 months. RESULTS: The mean seminal volume changed insignificantly between the two groups (4.15 +/- 1.95 vs. 4.10 +/- 1.95). There was a statistically significant increase of the sperm concentration in patients who received the alpha-blocker compared to those receiving placebo (24.76 +/- 9.45 vs. 13.15 +/- 11.55 millions/mL; P < .001). No improvement of the mean percentage of abnormal spermatozoa was observed in the treated patients, nor a statistically significant difference of sperm motility in the treated group compared to the placebo group. Side effects were not observed in the patients receiving terazosin treatment, or were so minimal that therapy was continued. The pregnancy rates did not differ between the two groups to a statistically significant degree. CONCLUSION: The administration of terazosin to patients with idiopathic oligozoospermia has a demonstrably positive effect, especially on sperm concentration. 相似文献