In this letter, we use squared iterative method with parameter checking to accelerate the convergence rate of expectation/conditional maximization (ECM) algorithm when estimating the channel parameters blindly in flat...
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In this letter, we use squared iterative method with parameter checking to accelerate the convergence rate of expectation/conditional maximization (ECM) algorithm when estimating the channel parameters blindly in flat fading nonGaussian channels, and further, we proposed automatic modulation classification (AMC) in flat fading non-Gaussian channels based on the proposed maximum likelihood estimator. The numerical results show that the proposed method can accelerate the convergence rate of ECM algorithm, and AMC based on the proposed method is faster than that based on ECM, while the accuracy of the former shows nearly no loss compared with that of the latter.
We used Gaussian modeling to depict the changes in finger photoplethysmographic (PPG) pulse during pregnancy in healthy women. We enrolled 70 healthy pregnant women and recorded their PPG pulses in 11-13 gestational w...
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We used Gaussian modeling to depict the changes in finger photoplethysmographic (PPG) pulse during pregnancy in healthy women. We enrolled 70 healthy pregnant women and recorded their PPG pulses in 11-13 gestational weeks, 20-22 gestational weeks, and 37-39 gestational weeks. Three independent positive Gaussian functions were utilized to decompose the pulses, and each Gaussian function extracted three key parameters: the peak amplitude (H), the peak position (T), and the half-width (W). The method of ANOVA and post-hoc multiple comparisons of mathematical statistics were utilized to study the differences of these parameters between the three trimesters. We found that in the first trimester H-1 increased significantly (H-1 : 49.7 +/- 10.3 versus 52.9 +/- 6.9, p < 0.05). T-2 and T-3 increased in the first trimester (T-2 : 28.1 +/- 2.8 versus 28.4 +/- 2.2, p > 0.05;T-3: 54.3 +/- 4.2 versus 56.3 +/- 4.3, p < 0.01), then decreased significantly (T-2 : 28.4 +/- 2.2 versus 27.3 +/- 2.2, T-3: 56.3 +/- 4.3 versus 54.7 +/- 5.2, p < 0.05). H-1 is associated with cardiac output, and T-2 and T-3 are associated with peripheral vascular resistance. The results of this study were consistent with the conclusion that healthy pregnant women exhibited high flow state of the cardiovascular system and their peripheral vascular resistance decreased first and then gradually recovered during pregnancy. This study indicated that PPG pulse could also reflect the changes in the maternal cardiovascular system during pregnancy.
In the process design and reuse of marine component products, there are a lot of heterogeneous models, causing the problem that the process knowledge and process design experience contained in them are difficult to ex...
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Room temperature ferromagnetism (RTFM) was observed in unirradiated rutile TiO2 single crystals prepared by the floating zone method due to oxygen vacancy (V-O) defects. D-D neutrons mainly collide elastically with Ti...
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Room temperature ferromagnetism (RTFM) was observed in unirradiated rutile TiO2 single crystals prepared by the floating zone method due to oxygen vacancy (V-O) defects. D-D neutrons mainly collide elastically with TiO2, producing V-O, titanium vacancies (V-Ti) and other point defects;the density and kind of defect is related to the neutron irradiation fluence. D-D neutron irradiation is used to regulate the concentration and type of defect, avoiding impurity elements. As the irradiation fluence increases, the saturation magnetization (M-s) first increases, then decreases and then increases. To verify the origin of RTFM, the CASTEP module was used to calculate the magnetic and structural properties of point defects in TiO2. V-O induces a 2.39 mu(B) magnetic moment, Ti3+ and F+ induce 1.28 mu(B) and 1.70 mu(B) magnetic moments, respectively, while V-Ti induces a magnetic moment of similar to 4 mu(B). Combining experimental and theoretical results, increases in V-O concentration lead to M-s increases;more V-O combine with electrons to form F+, inducing a smaller magnetic moment. V-O and V-Ti play a key role and M-s changes accordingly with larger fluence. V-O, F+ and V-Ti are the most likely origins of RTFM.
作者：
liu, JingyuanLegg, Jason C.Mo, MayZhang, xuwenXiamen Univ
Sch Econ Wang Yanan Inst Studies Econ Dept StatMOE Key Lab Econometr 422 Siming South Rd Xiamen 361005 Fujian Peoples R China Xiamen Univ
Fujian Key Lab Stat Sci 422 Siming South Rd Xiamen 361005 Fujian Peoples R China Amgen Inc
Global Biostat Sci Newbury Pk CA USA
Many treatments and drugs are intended to reduce the occurrence of negative events of interest, control the severity of the events, accelerate recovery from the events, or a combination of these effects. While assessi...
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Many treatments and drugs are intended to reduce the occurrence of negative events of interest, control the severity of the events, accelerate recovery from the events, or a combination of these effects. While assessing the clinical effect is typically the primary objective of a trial, testing the treatment effect on the health status of patients based on patient reported outcome (PRO) can be a useful component in determining the value of a treatment. Analysis of PROs in this setting, however, face the following challenges: the PRO value immediately after the event occurrence is often not captured, and the effect of the event on health status measured by the PRO is transient as subjects recover over time. Therefore, traditional statistical methods used to assess treatment effects suffer from low power for PROs. In this manuscript, we apply a kernel smoothing technique to estimate before- and after-event PRO values. We also propose new test outcomes based on observed and estimated PRO values and evaluate tests that focus on the tail distributions. We demonstrate that the tail distribution tests using the new outcomes can achieve high power under certain conditions.
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