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Strongly seasonal Proterozoic glacial climate in low palaeolatitudes:Radically different climate system on the pre-Ediacaran Earth

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Geoscience Frontiers 2016年第4期7卷 555-571页

作者： George E.Williams phillip W.Schmidt Grant M.Young Department of Earth Sciences University of AdelaideSA 5005Australia CSIRO Mineral Resources Flagship PO Box 52North RydeNSW 16FOAustralia Department of Earth Sciences University of Western OntarioLondonOntario N6A 5B7Canada

Proterozoic （pre-Ediacaran） glaciations occurred under strongly seasonal climates near sea level in low palaeolatitudes. Metre-scale primary sand wedges in Cryogenian periglacial deposits are identical to those actively forming, through the infilling of seasonal （winter） thermal contraction-cracks in perma- frost by windblown sand, in present-day polar regions with a mean monthly air temperature range of 40 ~C and mean annual air temperatures of -20 ~C or lower. Varve-like rhythmites with dropstones in Proterozoic glacial successions are consistent with an active seasonal freeze-thaw cycle. The seasonal （annual） oscillation of sea level recorded by tidal rhythmites in Cryogenian glacial successions indicates a significant seasonal cycle and extensive open seas. Palaeomagnetic data determined directly for Prote- rozoic glacial deposits and closely associated rocks indicate low palaeolatitudes： Cryogenian deposits in South Australia accumulated at 〈10% most other Cryogenian deposits at 〈20~ and Palaeoproterozoic deposits at 〈15~ palaeolatitude. Palaeomagnetic data imply that the Proterozoic geomagnetic field approximated a geocentric axial dipole, hence palaeolatitudes represent geographic latitudes. The Cry- ogenian glacial environment included glacier-flee, continental permafrost regions with ground frozen on a kyr time-scale, aeolian sand-sheets, extensive and long-lived open seas, and an active hydrological cycle. This palaeoenvironment confiicts with the ＇snowball Earth＇ and ＇slushball Earth＇ hypotheses, which cannot accommodate large seasonal changes of temperature near the equator. Consequently, their proponents have attempted to refute the evidence for strong seasonality by introducing Popperian ＇auxiliary assumptions＇. However, non-actualistic arguments that the Cryogenian sand wedges indicate diurnal or weakly seasonal temperature changes are based on misunderstandings of periglacial pro- cesses. Modelling of a strongly seasonal climate for a frozen-over Ear

关键词： Proterozoic Glaciation Periglacial structures Varves Paleoclimate Paleomagetism

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Relation between the permeability and the degree of coil overlap of polymer in the bulk state

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Chinese Chemical Letters 2007年第11期18卷 1423-1426页

作者： Quan Fu An Jin Wen Qian Meng Wang Yin Lu phillip Choi Key Laboratory of Macromolecule Synthesis and Functionalization （Ministry of Education） Zhejiang University Hangzhou 310027 PR China Faculty of Science Ningbo University Ningbo 315211 PR China Department of Chemical and Materials Engineering University of Alberta Edmonton Alberta T6G 2G6 Canada

Based on the expression of the index of coil interpenetration （i.e., the degree of coil overlap, ξb） of amorphous polymers in the bulk state proposed by Qian, the ξb was rewritten as ξb = ρb [η]θ/1.66 via Hory＇s intrinsic viscosity equation at them conditions. The ξb ofpoly （vinyl chloride）（PVC） dense membranes with different molecular weights and cellulose diacetate （CA） dense membranes prepared using different solvents were determined. The permeability, permeation coefficient （P） of nitrogen and permeation flux （J） of liquid through both membranes, respectively, was measured. P and J decreased exponentially with increasing ξb for PVC and CA membranes were revealed.

关键词： Degree of coil overlap Permeability Dense polymer membranes

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Comparison of performance of statistical models in forecasting monthly streamflow of Kizil River,China

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Water Science and Engineering 2010年第3期3卷 269-281页

作者： Shalamu ABUDU Chun-liang CUI James phillip KING Kaiser ABUDUKADEER Xinjiang Water Resources Research Institute Urumqi 830049 P. R. China Civil Engineering Department New Mexico State University NM 88001 USA Xinjiang Water Resources Bureau Urumqi 830000 P. R. China

This paper presents the application of autoregressive integrated moving average （ARIMA）, seasonal ARIMA （SARIMA）, and Jordan-Elman artificial neural networks （ANN） models in forecasting the monthly streamflow of the Kizil River in Xinjiang, China. Two different types of monthly streamflow data （original and deseasonalized data） were used to develop time series and Jordan-Elman ANN models using previous flow conditions as predictors. The one-month-ahead forecasting performances of all models for the testing period （1998-2005） were compared using the average monthly flow data from the Kalabeili gaging station on the Kizil River. The Jordan-Elman ANN models, using previous flow conditions as inputs, resulted in no significant improvement over time series models in one-month-ahead forecasting. The results suggest that the simple time series models （ARIMA and SARIMA） can be used in one-month-ahead streamflow forecasting at the study site with a simple and explicit model structure and a model performance similar to the Jordan-Elman ANN models.

关键词： time series model Jordan-Elman artificial neural networks model monthly streamflow forecasting

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Safe operation of online learning data driven model predictive control of building energy systems

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Energy and AI 2023年第4期14卷 536-549页

作者： phillip Stoffel Patrick Henkel Martin Ratz Alexander Kumpel Dirk Muller RWTH Aachen University E.ON Energy Research CenterInstitute for Energy Efficient Buildings and Indoor ClimateMathieustraße 10Aachen52074Germany

Model predictive control is a promising approach to reduce the CO 2 emissions in the building ***,the vast modeling effort hampers the widescale practical ***,data-driven process models,like artificial neural networks,are well-suited to automatize the ***,the underlying data set strongly determines the quality and reliability of artificial neural *** general,the validity domain of a machine learning model is limited to the data that was used to train *** based on system states outside that domain,so-called extrapolations,are unreliable and can negatively influence the control *** present a safe operation approach combined with online learning to deal with extrapolation in data-driven model predictive ***,the k-nearest neighbor algorithm is used to detect extrapolation to switch to a robust fallback *** continuously retraining the artificial neural networks during operation,we successively increase the validity domain of the artificial neural networks and the control *** apply the approach to control a building energy system provided by the BOPTEST *** compare controllers based on two data sets,one with extensive system excitation and one with baseline *** system is controlled to a fixed temperature set point in baseline ***,the artificial neural networks trained on this data set tend to extrapolate in other operating *** show that safe operation in combination with online learning significantly improves performance.

关键词： Data-driven model predictive control Online learning Novelty detection Artificial neural networks Building energy systems

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Cultural code

Cultural code

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作者： Penix-Tadsen phillip

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Lessons in bridge damage learned from the Wenchuan earthquake

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Earthquake Engineering and Engineering Vibration 2009年第2期8卷 275-285页

作者： W. phillip Yen Genda Chen Mark Yashinski Youssef Hashash Curtis Holu Wang Kehai GuoXiaodong Turner-Fairbank Highway Research Center of Federal Highway Administration （FWHA） Center for Transportation Infrastructure and Safety （CTIS） a National University Transportation Center at Missouri University of Science and Technology California Department of Transportation Representing the Earthquake Engineering Research Institute （EERI） University of Illinois at Urbana Champaign and Representing Geo-Engineering Earthquake Reconnaissance （GEER） Mid-America Earthquake Center （MAE） University of Illinois at Urbana Champaign Research Institute of Highway the Ministry of Communication of China Sichuan Province Highway Planning Survey Design and Research Institute China

A strong earthquake occurred in Wenchuan County, Sichuan Province, China, on May 12, 2008. Shortly after the earthquake, the Turner-Fairbank Highway Research Center of the Federal Highway Administration, in partnership with the Research Institute of Highways, the Ministry of Communication of China, led a reconnaissance team to conduct a post-earthquake bridge performance investigation of the transportation system in the earthquake affected areas. The U.S. transportation system reconnaissance team visited the area during July 20 24, 2008. This paper presents the findings and lessons learned by the team.

关键词： earthquake engineering bridge engineering post earthquake investigation

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Modeling of daily pan evaporation using partial least squares regression

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Science China(Technological Sciences) 2011年第1期54卷 163-174页

作者： ABUDU Shalamu CUI ChunLiang J. phillip KING Jimmy MORENO A. Salim BAWAZIR Xinjiang Water Resources Research Institute Urumqi 830049 China Civil Engineering Department New Mexico State University Las Cruces New Mexico 88001 USA

This study presented the application of partial least squares regression （PLSR） in estimating daily pan evaporation by utilizing the unique feature of PLSR in eliminating collinearity issues in predictor variables. The climate variables and daily pan evaporation data measured at two weather stations located near Elephant Butte Reservoir, New Mexico, USA and a weather station located in Shanshan County, Xinjiang, China were used in the study. The nonlinear relationship between climate variables and daily pan evaporation was successfully modeled using PLSR approach by solving collinearity that exists in the climate variables. The modeling results were compared to artificial neural networks （ANN） models with the same input variables. The resuits showed that the nonlinear equations developed using PLSR has similar performance with complex ANN approach for the study sites. The modeling process was straightforward and the equations were simpler and more explicit than the ANN black-box models.

关键词： modeling daily pan evaporation partial least squares regression artificial neural networks meteorological data

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An efficient semi-blind source extraction algorithm and its applications to biomedical signal extraction

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Science in China(Series F) 2009年第10期52卷 1863-1874页

作者： YE YaLan SHEU phillip C-Y ZENG JiaZhi WANG Gang LUKe School of Computer Science and Engineering University of Electronic Science and Technology of China Chengdu 610054 China Department of Electrical Engineering and Computer Science University of California Irvine CA 92697-2625 USA School of Life Science and Technology University of Electronic Science and Technology of China Chengdu 610054 China

In many applications, such as biomedical engineering, it is often required to extract a desired signal instead of all source signals. This can be achieved by blind source extraction （BSE） or semi-blind source extraction, which is a powerful technique emerging from the neural network field. In this paper, we propose an efficient semi-blind source extraction algorithm to extract a desired source signal as its first output signal by using a priori information about its kurtosis range. The algorithm is robust to outliers and spiky noise because of adopting a classical robust contrast function. And it is also robust to the estimation errors of the kurtosis range of the desired signal providing the estimation errors are not large. The algorithm has good extraction performance, even in some poor situations when the kurtosis values of some source signals are very close to each other. Its convergence stability and robustness are theoretically analyzed. Simulations and experiments on artificial generated data and real-world data have confirmed these results.

关键词： blind source extraction blind source separation independent component analysis electrocardiogram fetal ECG Atrial Fibrillation

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Robotic-assisted cholecystectomy: Current status and future application

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Laparoscopic, Endoscopic and Robotic Surgery 2022年第3期5卷 85-91页

作者： Simran Chandhok phillip Chao Jonathan Koea Sanket Srinivasa Upper GI Unit Department of SurgeryNorth Shore HospitalUniversity of AucklandAuckland 0620New Zealand

Robotic-assisted cholecystectomy(RC)is increasingly ***,its exact role remains unde-fined,with multiport conventional laparoscopic cholecystectomy(LC)being regarded as the established gold *** review aims to provide an overview of the evidence for RC and to define its current and future role.A literature search was performed on the PubMed and Medline databases to identify relevant articles published between 1994 and February *** evidence obtained was summarised in a narrative *** emphasis was placed on recent 10-year articles and studies of higher meth-odological *** is noninferior to *** robotic platform facilitates the application of minimally invasive surgery in a way conventional laparoscopy *** remains appropriate for the majority of patients requiring *** advantages of RC include inherent technical benefits,facilitating the learning of new surgical technology and its potential to reduce the risk of open conversion and bile leakage in certain populations(Mirizzi syndrome,complicated calculous disease,chronic liver disease and possibly malignancy).It also has increasing applicability to related biliary *** limitations include cost,loss of tactile feedback and the learning curve associated with initial *** applications of robotic surgical systems include utilisation in difficult cholecystectomy,cases of biliary malignancy,telerobotic surgery and telementoring.

关键词： Robotic-assisted cholecystectomy Laparoscopic cholecystectomy Bile duct injury repair

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Patterns of sperm use by twice-mated female Queensland fruit flies

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Insect Science 2022年第4期29卷 1159-1169页

作者： Jason Shadmany Siu F.Lee Thu N.M.Nguyen phillip W.Taylor Applied BioSciences Macquarie UniversityNorth RydeNSWAustralia CSIRO Land and Water Black MountainACTAustralia School of BioSciences University of MelbourneParkvilleVictoriaAustralia

Multiple mating by females,polyandry,is common in insects,including in tephritid fruit *** insects that remate commonly store sperm of multiple *** the sperm of different males contribute to paternity is an important element of sexual *** behavior and reproduction of the Queensland fruit fly(Qfly),Bactrocera tryoni,has been extensively investigated both in relation to understanding this economically important species’reproductive biology and in relation to implications for Sterile Insect Technique(SIT),whereby sterile flies are released to constrain reproduction of pest *** numerous studies of pre-and postcopulatory sexual selection in Qfly,there have been no direct studies of paternity patterns in polyandrous female *** used two morphologically distinguishable lines to investigate patterns of sperm use in *** two lines showed comparable mating performance evidenced by similar mating and remating frequency,copula duration,and proportion of second mate paternity(P2)between reciprocal *** mechanism of sperm usage,with P2 close to 0.5 immediately after the second mating followed by gradual decrease of P2 as females aged,is most consistent with stratification or repositioning of *** observed in the present study are compared with the available information from other tephritid fruit flies,and are discussed in relation to this species’reproductive biology,known patterns of sperm storage,and SIT.

关键词： muliple mating polyandry sperm competition sperm pecedence Tephritidac

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