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Basic Lithofacies-Succession Model for the Wumishan Cyclothems: Their Markov Chain Analysis and Regularly Vertical Stacking Patterns in the Third-Order Sequences 被引量:19
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作者 MEI Mingxiang, MA Yongsheng and GUO Qingyin Institute of Earth Sciences and Natural Resources, China University of Geosciences, Beijing 100083 China Petrochemical Corporation (SINOPEC), Beijing 100029 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第4期421-431,共11页
The Mesoproterozoic Wumishan Formation in the Jixian section of Tianjin is a succession of 3300-m-thick carbonate strata formed in a period of about 100 Ma (1310±20 Ma-1207±10 Ma). In this succession of stra... The Mesoproterozoic Wumishan Formation in the Jixian section of Tianjin is a succession of 3300-m-thick carbonate strata formed in a period of about 100 Ma (1310±20 Ma-1207±10 Ma). In this succession of strata, the carbonate metre-scale cyclic sequences belonging to peritidal type with an approximately symmetrical lithofacies-succession are best developed. The wide development of 1:4 stacking patterns shows that these metre-scale cyclic sequences are genetically related to the short-eccentricity cycles, which are called the Wumishan cyclothems that could truly represent sedimentary cycles. Generally, massive and thick-bedded calcareous dolomites and dolomitic limestones of stromatolite biostromes and thrombolite bioherms constitute the central part of the Wumishan cyclothems. The lower and upper parts consist of tidal flat dolostones, sandy-muddy dolostone and the top part is composed of lagoonal facies dolomitic shales with a paleosol cap. Therefore, an approximately symmetrical lithofacies-succession is formed. Many features such as the clear deepening and shoaling vectors of cyclothems, and all kinds of marks of fresh-water diagenesis indicate that the Wumishan cyclothems are the product of autocyclic sedimentation governed by allocyclic high-frequency sea-level changes. The results of a Markov chain analysis reaffirm the existence of the lithofacies-succession model of the Wumishan cyclothems. The boundaries of the Wumishan cyclothems are marked by the instantaneous exposed punctuated surface, which leads to the discrepancy between the cyclothems and the parasequences of the sequence stratigraphy terminology system. It is difficult to form a judgment that the time span of the Milankovitch cycles in the Precambrian is certainly equal to that of the Phanerozoic, but the regularly vertical stacking patterns of the seventh-order rhythms, sixth-order cyclothems and fifth-order parasequence sets still indicate their consistency with the duration of the Milankovitch cycles in the Phanerozoic. 展开更多
关键词 Wumishan cyclothems markov chain analysis MESOPROTEROZOIC Jixian section TIANJIN
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New Approach to Calculate the Unavailability of Identical Spares in Cold Spare Configuration
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作者 NYAN Win-aung 魏海军 柳霆 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期863-869,共7页
Cold spare is the most common configuration amongst the three types of configuration for systems used on board and for power generation systems. A new approach to calculate the unavailability of systems composed of id... Cold spare is the most common configuration amongst the three types of configuration for systems used on board and for power generation systems. A new approach to calculate the unavailability of systems composed of identical spares in cold spare configuration was proposed in this study. Instead of using the spare gate of dynamic fault tree( DFT) and the Markov analysis,AND gate of static fault tree used for calculating the unavailability of cold spare systems was proposed in this paper. By using this approach,unavailability of identical cold spare systems composed of nonrepairable spare components can be calculated exactly and systems composed of both repairable and nonreparable identical spare components can be estimated without building large Markov state diagram. 展开更多
关键词 cold spare spare gate AND gate failure percentage(FP) fault tree analysis markov analysis
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On essential topics of BYY harmony learning: Current status, challenging issues, and gene analysis applications 被引量:4
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作者 Lei XU 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2012年第1期147-196,共50页
As a supplementary of [Xu L. Front. Electr. Electron. Eng. China, 2010, 5(3): 281-328], this paper outlines current status of efforts made on Bayesian Ying- Yang (BYY) harmony learning, plus gene analysis appli- ... As a supplementary of [Xu L. Front. Electr. Electron. Eng. China, 2010, 5(3): 281-328], this paper outlines current status of efforts made on Bayesian Ying- Yang (BYY) harmony learning, plus gene analysis appli- cations. At the beginning, a bird's-eye view is provided via Gaussian mixture in comparison with typical learn- ing algorithms and model selection criteria. Particularly, semi-supervised learning is covered simply via choosing a scalar parameter. Then, essential topics and demand- ing issues about BYY system design and BYY harmony learning are systematically outlined, with a modern per- spective on Yin-Yang viewpoint discussed, another Yang factorization addressed, and coordinations across and within Ying-Yang summarized. The BYY system acts as a unified framework to accommodate unsupervised, su- pervised, and semi-supervised learning all in one formu- lation, while the best harmony learning provides novelty and strength to automatic model selection. Also, mathe- matical formulation of harmony functional has been ad- dressed as a unified scheme for measuring the proximity to be considered in a BYY system, and used as the best choice among others. Moreover, efforts are made on a number of learning tasks, including a mode-switching factor analysis proposed as a semi-blind learning frame- work for several types of independent factor analysis, a hidden Markov model (HMM) gated temporal fac- tor analysis suggested for modeling piecewise stationary temporal dependence, and a two-level hierarchical Gaus- sian mixture extended to cover semi-supervised learning, as well as a manifold learning modified to facilitate au- tomatic model selection. Finally, studies are applied to the problems of gene analysis, such as genome-wide asso- ciation, exome sequencing analysis, and gene transcrip- tional regulation. 展开更多
关键词 Bayesian Ying-Yang (BYY) harmonylearning harmony functional automatic model selec-tion Gaussian mixture hidden markov model (HMM)gated temporal factor analysis hierarchical Gaussianmixture manifold learning semi-supervised learning semi-blind learning genome-wide association exome se-quencing analysis gene transcriptional regulation
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Multiple hierarchy risk assessment with hybrid model for safety enhancing of unmanned subscale BWB demonstrator flight test 被引量:2
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作者 Yi LU Shuguang ZHANG +3 位作者 Zejing ZHANG Xuan ZHANG Peng TANG Shan FU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第12期2612-2626,共15页
To explore the low-speed characteristics of the Blended-Wing-Body(BWB)configuration for future civil aircraft,a series of unmanned subscale demonstrators have been developed and tested by our research team.During thi... To explore the low-speed characteristics of the Blended-Wing-Body(BWB)configuration for future civil aircraft,a series of unmanned subscale demonstrators have been developed and tested by our research team.During this process,specific safety risks deriving from uncertain design features,system unreliability,and insufficient personnel experience caused continuous flight test mishaps and the risk mechanism was not clear.Local and trial-and-error learning driven safety improvements took few effects on mishap prevention,so our focus was turned to look for systematic safety strategies.This paper establishes a systems theory based hybrid model to integrate the physical system reliability analysis techniques with the system dynamics method for illustrating the multiple risk interactions of the demonstrator flight test involving organizational,human resource and technical system factors.Using the prior BB-5 demonstrator as a case,the hybrid model simulation represents its historical risk evolution process,which verifies the model rationality.Derived risk control strategies reduced the mishap rate of a new demonstrator called BB-6 Sprit.The paper also shows the extended hybrid model can be applied on safety management of unmanned aerial vehicles from the initial period of vehicle development. 展开更多
关键词 Blended-wing-body Demonstration flight test markov analysis Risk assessment Strategy experiment System dynamics Systems theory
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Nerve decompression in diabetics with chronic nerve compression:update 2022
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作者 Arnold Lee Dellon 《Plastic and Aesthetic Research》 2022年第1期105-119,共15页
The number of people with diabetes worldwide has reached epidemic proportions.Diabetics are well-known to have chronic nerve compressions,and the prevalence of compressions exceeds 50% in those with neuropathy.The los... The number of people with diabetes worldwide has reached epidemic proportions.Diabetics are well-known to have chronic nerve compressions,and the prevalence of compressions exceeds 50% in those with neuropathy.The loss of sensation in the feet of people with diabetic neuropathy is the primary cause of their ulceration and amputation,as well as pain.The aim of this article is to update the reader on the current status of lower extremity nerve decompression in patients with diabetic neuropathy.A review of the history and literature related to the current approach to the patient with chronic nerve compression plus diabetic neuropathy was undertaken.The current evidence is overwhelmingly clear,in diabetics with neuropathy and a positive Tinel sign over the tibial nerve at the tarsal tunnel,that decompression,by neurolysis of lower extremity nerves,can relieve pain,restore sensation,and prevent ulceration and amputation.Furthermore,economic cost-benefit analysis by the Markov technique demonstrates that lower extremity nerve compression is not only cost-effective compared to standard medical care,but also increases the quality of life and life expectancy.The remaining barriers to acceptance and implementation of this proven surgical approach must lie in the education of physicians in training and re-education of diabetes educators,primary care providers and endocrinologists. 展开更多
关键词 Diabetic neuropathy NEUROLYSIS DECOMPRESSION markov analysis AMPUTATION
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