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Journal of Earth Science 2021年第6期32卷 1289-1299页

作者： tom Andersen O.Tapani Rämö Department of Geosciences University of OsloN-0316OsloNorway Department of Geosciences and Geography Geology and Geophysics Research ProgramUniversity of Helsinki00014HelsinkiFinland

Dehydration melting of metasupracrustal rocks at mid-to deep-crustal levels can generate water undersaturated granitic *** this study,we evaluate the potential of~1.89–1.88 Ga metasupracrustal rocks of the Precambrian of southern Finland as source rocks for the 1.86–1.79 Ga late-orogenic leucogranites in the region,using the Rhyolite-MELTS *** close in composition to leucogranite is produced over a range of realistic pressures(5 to 8 kbar)and temperatures(800 to 850℃),at 20%–30%of partial melting,allowing separation of melt from unmelted *** solid residue is a dry,enderbitic to charnoenderbitic ganulite depleted in incompatible components,and will only yield further melt above 1000–1050℃,when rapidly increasing fractions of increasingly calcic(granodioritic to tonalitic)melts are *** solid residue after melt extraction is incapable of producing syenogranitic magmas similar to the Mid-Proterozoic,A-type rapakivi granites on further *** granitic fraction of the syenogranitic rapakivi complexes must thus have been formed by a different chain of processes,involving mantle-derived mafic melts and melts from crustal rock types not conditioned by the preceding late-orogenic Svecofennian anatexis.

关键词： leucogranite rapakivi granite anatexis restite depleted granulite Finland

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A class of second-order sliding mode controller for servo systems

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控制理论与应用（英文版） 2012年第2期10卷 268-272页

作者： tom C. KONG Institute of Precision Engineering The Chinese University of Hong Kong

Sliding mode control （SMC） has been widely investigated in recent years. In this paper, a class of second- order SMC is proposed and used to achieve good tracking performance in servo systems. SMC has good robustness to the disturbances, but conventional SMC uses a sign function to drive the error on the sliding surface, which could generate chattering effect. In order to avoid this problem, our improved SMC uses the integral of the sign function. Coupled with an exponential reaching law, the new SMC can better suppress torque disturbances and chatter, This paper first gives the derivation of the new SMC. Simulation and experimental results are then carried out to demonstrate its tracking performance and robustness against torque disturbance and chatter.

关键词： Sliding mode control (SMC) Servo system Position tracking Disturbance suppression

Epidemiology of perforating peptic ulcer:A population-based retrospective study over 40 years

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World Journal of Gastroenterology 2020年第35期26卷 5302-5313页

作者： Aydin Dadfar tom-Harald Edna Department of Surgery Levanger HospitalNord-Trøndelag Hospital TrustLevanger 7600Norway Institute of Clinical and Molecular Medicine Norwegian University of Science and TechnologyTrondheim 7491Norway

BACKGROUND The incidence of peptic ulcer disease has decreased during the last few decades,but the incidence of reported peptic ulcer complications has not *** peptic ulcer(PPU)is a severe form of the *** To assess trends in the incidence,presentation,and outcome of PPU over a period of 40 *** This was a single-centre,retrospective,cohort study of all patients admitted to Levanger Hospital,Norway,with PPU from 1978 to *** patients were identified in the Patient Administrative System of the hospital using International Classification of Diseases(ICD),revision 8,ICD-9,and ICD-10 codes for perforated gastric and duodenal *** reviewed the medical records of the patients to retrieve *** statistics were available for all *** incidence of PPU was analysed using Poisson regression with perforated ulcer as the dependent variable,and sex,age,and calendar year from 1978 to 2017 as *** survival analysis was performed to compare long-term survival over the four *** Two hundred and nine patients were evaluated,including 113(54%)***(22%)patients were older than 80 *** age increased from the first to the last decade(from 63 to 72 years).The incidence rate increased with increasing age,but we measured a decline in recent decades for both sexes.A significant increase in the use of acetylsalicylic acid,from 5%(2/38)to 18%(8/45),was observed during the study *** increased significantly over the 40 years of the study,with 22%(10/45)of the patients having an American Society of Anaesthesiologists(ASA)score 4-5 in the last decade,compared to 5%(2/38)in the first ***-nine percent(81/209)of the patients had one or more postoperative *** 100-day mortality and long-term survival were associated with ASA score,without significant variations between the *** Declining incidence rates occurred in recent years,but the patients were olde

关键词： Perforated peptic ulcer American Society of Anaesthesiologists classification Charlson Comorbidity Index Gastric ulcer Duodenal ulcer Epidemiology Incidence Clavien-Dindo classification of complications Mortality

Quine on Quantification and Existence

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Frontiers of Philosophy in China 2016年第1期11卷 54-72页

作者： tom Stoneham Department of Philosophy University of York YO 10 5DD UK

Quine＇s justly famous paper ＂On What There Is＂ introduced a criterion of ontological commitment which has been almost universally accepted by analytic philosophers ever since. In this paper 1 try to unpack some of the substantive and controversial philosophical commitments that are presupposed by this criterion. The aim is not to show that the criterion is incorrect, but merely that it is not as obvious as it is taken to be by many, and that we might have reasons to explore alternative ways of thinking about ontological commitments.

关键词： determinacy existence identity logic metaphysics ontology,quantification Quine

Discrete Maximum Principle for Poisson Equation with Mixed Boundary Conditions Solved by hp-FEM

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Advances in Applied Mathematics and Mechanics 2009年第2期1卷 201-214页

作者： tomáš Vejchodský Pavel Šolín Institute of Mathematics Czech Academy of SciencesŽitná25CZ-11567 Praha 1Czech Republic Department of Mathematics and Statistics University of NevadaRenoUSAInstitute of ThermomechanicsCzech Academy of SciencesDolejˇskova 5Praha 8CZ-18200Czech Republic

We present a proof of the discrete maximum principle(DMP)for the 1D Poisson equation−u"=f equipped with mixed Dirichlet-Neumann boundary *** problem is discretized using finite elements of arbitrary lengths and polynomial degrees(hp-FEM).We show that the DMP holds on all meshes with no limitations to the sizes and polynomial degrees of the elements.

关键词： Discrete maximum principle hp-FEM Poisson equation mixed boundary conditions

An Efficient and Flexible Deterministic Framework for Multithreaded Programs

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Journal of Computer Science & Technology 2015年第1期30卷 42-56页

作者：卢凯周旭王小平 tom Bergan 陈沉 Science and Technology on Parallel and Distributed Processing Laboratory National University of Defense Technology Changsha 410073 China College of Computer National University of Defense Technology Changsha 410073 China Department of Computer Science and Engineering University of Washington Seattle WA 98195-2350 U.S.A.

Determinism is very useful to multithreaded programs in debugging, testing, etc. Many deterministic ap- proaches have been proposed, such as deterministic multithreading （DMT） and deterministic replay. However, these sys- tems either are inefficient or target a single purpose, which is not flexible. In this paper, we propose an efficient and flexible deterministic framework for multithreaded programs. Our framework implements determinism in two steps： relaxed determinism and strong determinism. Relaxed determinism solves data races eificiently by using a proper weak memory consistency model. After that, we implement strong determinism by solving lock contentions deterministically. Since we can apply different approaches for these two steps independently, our framework provides a spectrum of deterministic choices, including nondeterministic system （fast）, weak deterministic system （fast and conditionally deterministic）, DMT system, and deternfinistic replay system. Our evaluation shows that the DMT configuration of this framework could even outperform a state-of-the-art DMT system.

关键词： determinism multithreading framework flexible

Marx and the Transition Problem

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Frontiers of Philosophy in China 2014年第3期9卷 342-349页

作者： tom Rockmore Department of Philosophy Peking University Beijing 100871 China

Marx is concerned with theory that not only interprets but also changes the world. His central concern lies in the transition from capitalism to communism. This paper examines three ways that he might understand this ... 详细信息

关键词： transition capitalism communism crisis politics proletariat

Polishing and Reviewing ***'s New Book—Chinese Mei Flower Cultivars:An Enlarged Edition of Mei Cultivars in Colour Written by Chen Jun-yu

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北京林业大学学报 2010年第S2期32卷 257-258页

作者： tom Hazenberg Lakehead University

Mei tree(Prunus mume *** Zucc.) is originated in central and western China,being a famous traditional flowering *** is so highly

关键词：责任编辑

Impact of trimming intensity on the growth of mangrove in Iran

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Journal of Arid Land 2024年第12期16卷 1701-1713页

作者： Maryam MOSLEHI Akram AHMADI tom PYPKER Research Division of Natural Resources Hormozgan Agricultural and Natural Resources Research and Education CenterAgricultural ResearchEducation and Extension Organization(AREEO)Bandar Abbas ***Iran Research Division of Natural Resources Golestan Agricultural and Natural Resources Research and Education CenterAREEOGorgan ***Iran Thompson Rivers University Kamloops V2C 0C8Canada

Mangrove forests in southern Iran are of high ecological and economic *** forests are being threatened because of uncontrolled harvesting to provide fodder for *** objective of this study is to provide recommendations for appropriate harvesting intensities by quantifying the effect of different harvesting intensities on vegetative and vigor characteristics of mangrove *** study was conducted using a randomized complete block design comprising four treatments(10.00%,20.00%,and 30.00% trimming,along with a control)replicated three *** characteristics were measured before and after trimming(five-year period)and analyzed using generalized linear model statistical *** growths of the average diameter of canopy,canopy area,canopy volume,canopy height,tree height,and collar diameter in the control treatment were all significantly higher than those in the trimming *** addition,there was a decreasing trend in leaf fresh and dry mass,leaf area index,total area of canopy leaves,and health status of tree in the trimming *** example,the percentage change in fresh and dry leaf mass in the control treatment was positive(29.87% and 38.31%,respectively),whereas the trimming treatments of 10.00%,20.00% and 30.00% had negative effects(-7.01% and -4.79%,-11.32% and -14.30%,and -15.84% and -17.29%,respectively).In addition,the changes in leaf area index in the control(4.95%)and 30.00% trimming(-24.57%)treatments were the highest and lowest,*** percentage change in soil organic matter in the control,10.00%,20.00%,and 30.00% treatments were 22.94%,-9.90%,-16.91%,and -18.68%,*** study demonstrated that gray mangrove trees were highly sensitive to canopy trimming,with even minimal trimming intensities negatively affecting vegetative growth and soil organic ***,it is recommended that cutting and trimming of mangrove trees should be prevented even at low intensity to preserve mangrov

关键词： trimming mangrove ecosystem vegetative characteristic harvest intensity soil organic matter Khamir Port

Recurrence and rejection in liver transplantation for primary sclerosing cholangitis

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World Journal of Gastroenterology 2012年第1期18卷 1-15页

作者： Bjarte Fosby tom H Karlsen Espen Melum Department of Transplantation Surgery Clinic for Specialized Medicine and Surgery Oslo University Hospital Norwegian Primary Sclerosing cholangitis Research Center Clinic for Specialized Medicine and Surgery Oslo University Hospital Research Institute for Internal Medicine Oslo University Hospital

Primary sclerosing cholangitis (PSC) is a chronic progressive inflammatory disease affecting the bile ducts, leading to f ibrosis and eventually cirrhosis in most patients. Its etiology is unknown and so far no effective medical therapy is available. Liver transplantation (LTX) is the only curative treatment and at present PSC is the main indication for LTX in the Scandinavian countries. Close to half of the PSC patients experience one or more episodes of acute cellular rejection (ACR) following transplantation and approximately 1/5 of the transplanted patients develop recurrent disease in the graft. In addition, some reports indicate that ACR early after LTX for PSC can infl uence the risk for recurrent disease. For these important post-transplantation entities affecting PSC patients, we have reviewed the current literature on epidemiology, pathogenesis, treatment and the possible infl uence of rejection on the risk of recurrent disease in the allograft.

关键词： Liver transplantation Primary sclerosing cholangitis Rejection Recurrence