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21.
The NESPOLE! System is a speech communication system designed to support multilingual interaction between common users and providers of e-commerce services over the Internet. The core of the system is a distributed interlingua-based speech-to-speech translation system, which is supported by multimodal capabilities that allow the two parties participating in the communication to share Web pages and graphical content which can be annotated using gestures. We describe the unique features and considerations behind the design and implementation of this system, and evaluate these within the context of a constructed full prototype of the system that was developed for the domain of travel planning.  相似文献   
22.
Morphologically rich languages pose a challenge for statistical machine translation (SMT). This challenge is magnified when translating into a morphologically rich language. In this work we address this challenge in the framework of a broad-coverage English-to-Arabic phrase based statistical machine translation (PBSMT). We explore the largest-to-date set of Arabic segmentation schemes ranging from full word form to fully segmented forms and examine the effects on system performance. Our results show a difference of 2.31 BLEU points averaged over all test sets between the best and worst segmentation schemes indicating that the choice of the segmentation scheme has a significant effect on the performance of an English-to-Arabic PBSMT system in a large data scenario. We show that a simple segmentation scheme can perform as well as the best and more complicated segmentation scheme. An in-depth analysis on the effect of segmentation choices on the components of a PBSMT system reveals that text fragmentation has a negative effect on the perplexity of the language models and that aggressive segmentation can significantly increase the size of the phrase table and the uncertainty in choosing the candidate translation phrases during decoding. An investigation conducted on the output of the different systems, reveals the complementary nature of the output and the great potential in combining them.  相似文献   
23.
In this paper, delamination initiation and propagation of reinforced fibrous composite laminate, in single and mixed mode, are numerically predicted by taking into account the existence of imperfect interfaces between the plies. The bonding conditions between layers are characterised by jumps in displacements which are proportional to the traction stresses. In order to describe the interface damage an approach based on the indirect use of fracture mechanics considering a softening stress-relative displacements law is presented. The accuracy of the predictions is evaluated in single-mode delamination tests, in the mixed-mode bending test, and in a structural configuration consisting of the debonding of a new woven laminated composite reinforced by particles of date cores for orthopedic use. The interface is regarded as being a whole of several interfacial bonds. Each bond is supposed to be made up of three stiffnesses acting in the three directions.  相似文献   
24.
We describe a 14 year-old boy with a pineal germ cell tumor which secreted beta HCG. Serum testosterone levels were markedly elevated with concomitant decreased LH secretion. 24-h serum melatonin levels were suppressed and lacked the normal nocturnal rise. Pineal radiation therapy was followed by tumor regression and the diminution of beta HCG stimulated testosterone, which in turn inhibited melatonin and LH. When beta HCG and testosterone were normalized after tumor radiation, a recovery of normal melatonin and LH secretory pattern occurred. These results indicate that circulating testosterone down-regulates pineal melatonin.  相似文献   
25.
Stellate ganglion block (SGB) is considered to increase blood flow to the governing area, but recent studies have shown the decrease of common carotid arterial blood flow in the unblocked side following SGB. We investigated the influence of SGB on bilateral cerebral blood flow and oxygenation using a regional oxygen saturation (rSO2) monitor, TOS-96 (TOSTEC, Japan). The changes of blood volume (hemoglobin index: Hb I) and rSO2 were measured in twenty adult patients who underwent SGB at the transverse process of the C 6 vertebra. Prior to the investigation, two sensors were calibrated and placed on either side of each patient's forehead in order to see the difference. There were significant increases in rSO2 and Hb I in the blocked side and decreases in rSO2 and Hb I in the contralateral side. These results suggest that blood flow in the blocked side following SGB increases with decreased blood flow in the unblocked side. Patients with cerebral vascular disease undergoing SGB might be at risk of a decrease in cerebral blood flow in the unblocked area.  相似文献   
26.
Fixed beds, exchanging mass or energy with a flowing fluid according to a linear phenomenological law, are considered. When the plant is alternated periodically between two sets of operating conditions, the state of the fixed bed converges to a limit cycle. The nature of this cycle is explored for co-current and counter-current operation.  相似文献   
27.
Withanolide D, the major component of the leaves of Withania somnifera chemotype II, is a steroidal lactone of the withanolide type, isomeric with withaferin A. It has been identified as 5, 6β-epoxy-4β, 20α-dihydroxy-1-oxo-(5β)witha-2, 24-dienolide. The structure has been elucidated by NMR measurements and by chemical degradation to 4β-acetoxy-5,6β-epoxy (5β) pregnan-1, 20-dione.  相似文献   
28.
This research evaluates the aesthetics and usability of various in-vehicle electronic navigation map configurations. Study 1 adapted the aesthetics scale (Lavie and Tractinsky, 2004) to accommodate evaluations of map displays. Study 2 examined map displays that vary in the amount of data presented, their abstraction level and color schema, using objective and subjective usability measures. Maps with minimal detail produced best performances and highest evaluations. Abstractions were found to be advantageous when combined with reduced amount of detail and specific color schemas. Moderate abstractions were sufficient for obtaining the desired benefits. The color schema mainly affected the objective measures, pointing to the importance of good contrast between the cursor and the map colors. Study 3 further examined map schemas. Color schemas again had no effect on the perceptions of aesthetics and usability. Overall, similar results and high correlations were found for the perceived aesthetics and usability scales, indicating the connection between perceived aesthetics and usability. Lower correlations were found between the actual usability (performance) and the aesthetics scale. Finally, users’ usability evaluations were not always in line with their actual performance, pointing to the importance of using objective usability measures.  相似文献   
29.
STUDY OBJECTIVE: To evaluate the clinical relevance of circulating tumor necrosis factor-alpha (TNF alpha) in subjects with advanced acutely decompensated congestive heart failure (CHF) and to determine the modulatory effect of clinical interventions on short-term elaboration of this cytokine. DESIGN: Prospective, case-controlled study. SETTING: Inpatient and outpatient (hospital and clinic), at regional academic medical center. PATIENT INTERVENTIONS: Plasma concentrations of TNF alpha were determined in 25 healthy, normal control subjects and in 29 noncachectic patients with advanced CHF (mean ejection fraction = 16 +/- 6%) who required hospitalization for i.v. diuretic and/or inotropic therapy despite optimization of oral medical regimens. CHF patients were divided into two groups: diuretic responsive (group A; n = 6) and diuretic resistant requiring inotropic support (group B; n = 23). Group B was randomly allocated to receive either i.v. dobutamine (n = 13) or milrinone (n = 10) for 72 h. TNF alpha levels in CHF patients were measured serially at baseline, at 6 h, at 48 h, at 72 h, and at 1-week follow-up after hospital discharge. RESULTS: Plasma TNF alpha levels at baseline in CHF patients were 4.0 +/- 1.1 pg/mL (range, 0.5 to 6.5 pg/ mL) and 2.5 +/- 0.6 pg/mL (range, 0.5 to 6.8 pg/mL) in groups A and B, respectively, which were significantly different (p < 0.002) from normal subjects (0.89 +/- 0.40 pg/mL; range, 0.5 to 9.7 pg/mL). Despite clinically successful therapy with i.v. diuretics, dobutamine, or milrinone, plasma levels of this cytokine remained unchanged. Plasma TNF alpha in CHF patients measured in recovery (1 week after hospital discharge) was 5.1 +/- 1.2 pg/mL (range, 1.0 to 9.9 pg/mL) and 3.9 +/- 0.8 pg/mL (range, 0.5 to 8.7 pg/mL) in groups A and B, respectively. CONCLUSION: These findings suggest that although noncachectic patients with chronic heart failure who suffer acute decompensation elaborate significantly higher circulating levels of TNF alpha compared with healthy control subjects, no significant reduction or alteration in circulating TNF alpha is noted in the short-term follow-up despite clinical improvement.  相似文献   
30.
The theoretical predictions of doubled overall efficiency for plate distillation columns operated in the controlled cycling mode have not been confirmed by pilot scale experiments. In an attempt to circumvent the hydrodynamic problems causing this failure, we have found a new periodic operating mode where the liquid flow is manipulated directly, and not indirectly through pulsations of the vapour flow rate (as in controlled cycling).In this paper we present the theory of stepwise periodic distillation, under assumptions allowing a comparison with known results for controlled cycling. We show that the two processes have the same asymptotic efficiencies for large values of the number of trays while periodic stepwise distillation is slightly more efficient than controlled cycling for a finite number of trays  相似文献   
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