The Mkv evolutionary model, based on minor modifications to models of molecular evolution, is being increasingly used to infer phylogenies from discrete morphological data, often producing different ...results from parsimony. The critical difference between Mkv and parsimony is the assumption of a “common mechanism” in the Mkv model, with branch lengths determining that probability of change for all characters increases or decreases at the same tree branches by the same exponential factor. We evaluate whether the assumption of a common mechanism applies to morphology, by testing the implicit prediction that branch lengths calculated from different subsets of characters will be significantly correlated. Our analysis shows that DNA (38 data sets tested) is often compatible with a common mechanism, but morphology (86 data sets tested) generally is not, showing very disparate branch lengths for different character partitions. The low levels of branch length correlation demonstrated for morphology (fitting models without a common mechanism) suggest that the Mkv model is too unrealistic and inadequate for the analysis of most morphological data sets.
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BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This open access book charts how South Africa’s gold mines have systematically suppressed evidence of hazardous work practices and the risks associated with mining. For most of the twentieth century, ...South Africa was the world’s largest producer of gold. Although the country enjoyed a reputation for leading the world in occupational health legislation, the mining companies developed a system of medical surveillance and workers’ compensation which compromised the health of black gold miners, facilitated the spread of tuberculosis, and ravaged the communities and economies of labour-sending states. The culmination of two decades of meticulous archival research, this book exposes the making, contesting, and unravelling of the companies’ capacity to shape – and corrupt – medical knowledge.
In this paper, a mid- to long-term runoff forecast model is developed using an ideal point fuzzy neural network-Markov (NFNN-MKV) hybrid algorithm to improve the forecasting precision. Combining the ...advantages of the new fuzzy neural network and the Markov prediction model, this model can solve the problem of stationary or volatile strong random processes. Defined error statistics algorithms are used to evaluate the performance of models. A runoff prediction for the Si Quan Reservoir is made by utilizing the modelling method and the historical runoff data, with a comprehensive consideration of various runoff-impacting factors such as rainfall. Compared with the traditional fuzzy neural networks and Markov prediction models, the results show that the NFNN-MKV hybrid algorithm has good performance in faster convergence, better forecasting accuracy and significant improvement of neural network generalization. The absolute percentage error of the NFNN-MKV hybrid algorithm is less than 7.0%, MSE is less than 3.9, and qualification rate reaches 100%. For further comparison of the proposed model, the NFNN-MKV model is employed to estimate (training and testing for 120-month-ahead prediction) and predict river discharge for 156 months at Weijiabao on the Weihe River in China. Comparisons among the results of the NFNN-MKV model, the WNN model and the SVR model indicate that the NFNN-MKV model is able to significantly increase prediction accuracy.
Editor D. Koutsoyiannis; Associate editor Y. Gyasi-Agyei
As the technology is achieving a non-feasible zenith of complexity and quality in video, it is important to maintain the related size of each file at a low level to be able to run the video on ...devices with limited space like phones. In this regard, different video codecs and containers have been brought forward so that a lower level of information redundancy and processing delay would be sustained. Currently, five codecs namely VP8, VP9, AVC (advanced video compression), and HEVC (High-Efficiency Video Coding) along with three video containers including MP4, MKV (Matroska Multimedia Container), and AVI (Audio-Video Interleaved) are the most considered video compression standards and containers, respectively. Thus, this work aims at the evaluation of these codecs and also their combination with the containers. Moreover, distinct quality metrics that can show the variation lying in between are studied using different metrics. The performance is obtained in terms of PSNR (Peak Signal-to-Noise Ratio), MSE (Mean Squared Error), SSIM (Structural Similarity Index), and VMAF (Video Multi-Method Assessment Fusion) using FFmpeg in Linux distribution to determine the best selection of the codecs and containers.
Objective: To assess the validity of sexual behaviour data collected from African adolescents using five methods. Methods: 9280 Tanzanian adolescents participated in a biological marker and face to ...face questionnaire survey and 6079 in an assisted self-completion questionnaire survey; 74 participated in in-depth interviews and 56 person weeks of participant observation were conducted. Results: 38% of males and 59% of females reporting sexual activity did so in only one of the two 1998 questionnaires. Only 58% of males and 29% of females with biological markers consistently reported sexual activity in both questionnaires. Nine of 11 (82%) in-depth interview respondents who had had biological markers provided an invalid series of responses about sex in the survey and in-depth interview series. Only one of six female in-depth interview respondents with an STI reported sex in any of the four surveys, but five reported it in the in-depth interviews. Conclusion: In this low prevalence population, biological markers on their own revealed that a few adolescents had had sex, but in combination with in-depth interviews they may be useful in identifying risk factors for STIs. Self-reported sexual behaviour data were fraught with inconsistencies. In-depth interviews seem to be more effective than assisted self-completion questionnaires and face to face questionnaires in promoting honest responses among females with STIs. Participant observation was the most useful method for understanding the nature, complexity, and extent of sexual behaviour.
As an alternative to parsimony analyses, stochastic models have been proposed (
Lewis, 2001; Nylander et al., 2004) for morphological characters, so that maximum likelihood or Bayesian analyses may ...be used for phylogenetic inference. A key feature of these models is that they account for ascertainment bias, in that only varying, or parsimony-informative characters are observed. However, statistical consistency of such model-based inference requires that the model parameters be identifiable from the joint distribution they entail, and this issue has not been addressed.
Here we prove that parameters for several such models, with finite state spaces of arbitrary size, are identifiable, provided the tree has at least eight leaves. If the tree topology is already known, then seven leaves suffice for identifiability of the numerical parameters. The method of proof involves first inferring a full distribution of both parsimony-informative and non-informative pattern joint probabilities from the parsimony-informative ones, using phylogenetic invariants. The failure of identifiability of the tree parameter for four-taxon trees is also investigated.
MKV carrier vehicle sensor calibration
Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE,
04/2009
Conference Proceeding
Multiple Kill Vehicle (MKV) is a new type of ballistic missile interceptor composed of a carry vehicle and multiple kill vehicles to intercept incoming targets during the midcourse phase. During the ...combat of MKV, the allocation of interceptors is the key technology in decision-making strategy. In this paper, an interception revenue model was established as the optimal evaluation criterion of interceptor allocation. And the multi-information particle swarm optimization was proposed to find the scheme with maximum revenue. By introducing neighbor information, the stability and optimal performance of traditional particle swarm optimization is improved. The simulation results show that the proposed MPSO algorithm significantly enhanced the revenue and success rate of interception by preventing premature convergence on local optima.
New fuzzy neural networkMarkov model and application in mid- to long-term runoff forecast Shi, Biao; Chang Hua Huauthor Room 302, Xian Research Institute of High Technology, China; Xin Hua YuauthorCivil and Hydraulic Engineering, Ning Xia University, Yin Chuan750021, Ning Xia, ChinaEngineering Research Centre, Ministry of Education on Water Resources Efficient Use in Arid Modern Agriculture, Yin Chuan750021, China ...
2015
Journal Article
Several steganographic algorithms have been proposed for protecting message secrecy against unauthorized "reads". The most used method for hiding a message relies on embedding the secret message in ...Least Significant Bit (LSB) on the cover object. Though various digital formats have been proposed in literature to be used as cover objects, little attention has been paid on Matroska multimedia containers. In this work, we propose a practical method for applying steganography in these types of files. The proposed method consists of three distinct phases. The first one encrypts the hidden message, the second embeds it to the stego cover, while at the final step the stego cover is attached to a Matroska container. We tested our approach in various scenarios in order to evaluate the introduced overhead. Results shows that the use of several sizes for TXT and WAV files did not introduce considerable overhead. Depending on the file size the introduce overhead can be between 1 to 3 seconds.
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