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131.
Xu Lang Bhandari Saurabh Chen Jiming Glasgow Jonathan Mavrikakis Manos 《Topics in Catalysis》2020,63(7-8):762-776
Topics in Catalysis - Palladium has been shown to be an effective catalyst for chloroform hydrodechlorination, which serves as a promising treatment method for industrial chloroform waste. To... 相似文献
132.
K. P. Karunakaran Saurabh Agrawal Pankaj D. Vengurlekar Onkar S. Sahasrabudhe Vishal Pushpa Ronald H. Ely 《IIE Transactions》2005,37(4):291-302
Rapid Prototyping (RP) is a technology based on a “divide-and-conquer” strategy that enables automatic physical realization of a design without any special tooling. However, existing RP processes suffer from staircase defects since they are all based on 2.5-axis kinematics. To minimize the error due to staircase defects parts are normally built from very thin layers typically with thickness values of 0.010 to 0.300 mm. Therefore, hundreds of layers are required to produce a typical object making RP a slow and costly process. To overcome these limitations, a new RP process called Segmented Object Manufacturing (SOM) is proposed in this paper. SOM makes use of three-axis kinematics in conjunction with a novel slicing method. Slicing in SOM is based on certain visibility-based considerations and is independent of the part accuracy. Since only a few thick layers are used in the SOM technique, a part can be produced faster and cheaper with an accuracy comparable to that of CNC machining. 相似文献
133.
Here an effort is made to use human electrocardiogram as a tool of biometric analysis for authentication. The proposed method is based on first accurate extraction of characteristic features from each ECG and then design of a suitable classification methodology to comment on the authenticity. As the feature matrix is a huge one, Principal Component Analysis (PCA) is applied to avoid handling of large amount of data. Next, the reduced features from PCA are fitted into a quadratic polynomial model by the method of least square. Then the fitted values for the allowed set of data is obtained and the range over which they vary, provides the signature matrix of a person. Finally the classification is done by a comparison based on nearest neighbor method. The method is tested on ECG of 20 individuals taken from PTB database. This method has accuracy more than 95% with the best fit modeling which becomes only 80% without data modeling proving the importance of best fit modeling of data before classification. This accuracy is comparable with conventional biometric techniques; moreover, ECG biometric can be used with other authentication scheme, with ECG providing liveliness proof. 相似文献
134.
Wireless Personal Communications - The ability to access data from remote locations is meant possible with the help of computer networks. These networks may be wired or wireless. Modern... 相似文献
135.
Wireless Personal Communications - In every walk of life communication plays a vital role. We use five sensory features namely optical, auditory, olfactory, gustatory, and tactile to communicate.... 相似文献
136.
Human bond communication is termed as communicating the observed data by the five sensory organ from one side to the other via proper channel. We have already achieved success in transmission of two types of data which is observed by the two organs, i.e., eye and ear. Still we have not yet succeeded in the transfer of data detected by the rest three organs namely Nose, Tongue, and Touch. “A Novel Standard Strip And Scaling Technique For Transferring Taste” is a proposed novel method through which we can transfer our taste (gustatory) feeling to others.
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139.
OBJECTIVES: To define the incidence and severity of ovarian hyperstimulation syndrome (OHSS) occurring in oocyte donors. METHODS: Women (n = 149) aged 31.3 +/- 4.8 years (mean +/- S.D., range 21-41 years) participated as designated oocyte donors and underwent 400 consecutive cycles of controlled ovarian stimulation using human menopausal gonadotropin following pituitary downregulation with gonadotropin-releasing agonist. Patients were monitored by serial transvaginal ultrasound examinations and serum estradiol (E2) determinations. Oocytes (15.6 +/- 7.5 per aspiration; range 2-57) were harvested by ultrasound-directed transvaginal follicle aspiration 36 h following the intramuscular injection of human chorionic gonadotropin (hCG). Follow-up examination occurred 1 and 2 weeks post-aspiration. RESULTS: On the day of hCG injection E2 levels ranged from 512 to 13,502 pg/ml (mean 2902.7 +/- 1486.9 pg/ml). Over the next few weeks the degree of hyperstimulation in donors was staged: mild 65% (grade I, n = 98; grade II, n = 162); moderate 33.5% (grade III, n = 120; grade IV, n = 14); severe 1.5% (grade V, n = 6; grade VI, n = 0). Associated preaspiration E2 levels were: grade I, 1120 +/- 424 pg/ml; grade II, 2084 +/- 613 pg/ml; grade III, 3785 +/- 1713 pg/ml; grade IV, 5370 +/- 1264 pg/ml; grade V, 4286 +/- 1100 pg/ml. Worsening OHSS was associated with increasing levels of E2. There were no serious complications and hospitalization was not required. All symptoms resolved within 30 days of aspiration, disappearing by the time of the first menstrual flow in women of grade-III or lower stage. CONCLUSION: Although oocyte donors commonly experienced exaggerated levels of serum E2 they rarely (< 2%) developed severe OHSS. This may be attributable to their lack of embryo transfer which avoids exacerbating the illness. 相似文献
140.
Effect of caesium and cerium,l-alanine and caesium +l-alanine impurities are investigated on ferroelectric and pyroelectric properties of TGS crystals. Dielectric constant and loss, pyroelectric coefficient, spontaneous polarization and coercive field measurements of these modified crystals, as a function of temperature are reported. Caesium and cerium did not affect the electrical properties of TGS crystals significantly, whereasl-alanine- and, especially, Cs +l-alanine-doped TGS crystals exhibited promising improvements in pyroelectric properties, up to 48 °C, as compared to pure TGS crystals. 相似文献