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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

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

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

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

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

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

Interaction design for paediatric emergency VR training

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Virtual Reality & Intelligent Hardware 2020年第4期2卷 330-344页

作者： TJ MATTHEWS Feng TIAN tom DOLBY Centre for Digital Entertainment Bournemouth UniversityUK Faculty of Science&Technology Bournemouth UniversityUK Head of Simulations AiSolveUK

Background Virtual reality(VR)in healthcare training has increased adoption and support,but efforts are still required to mitigate usability *** This study conducted a usability study of an in-use emergency medicine VR training application,available on commercially available VR hardware and with a standard interaction *** users without prior VR experience but with relevant medical expertise completed two simulation scenarios for a total of 18 recorded *** completed NASA Task Load Index and System Usability Scale questionnaires after each session,and their performance was recorded for the tracking of user *** and Conclusions Our results showed a medium(and potentially optimal)Workload and an above average System Usability *** was significant improvement in several factors between users'first and second sessions,notably increased Performance *** errors with the strongest correlation to usability were not directly tied to interaction design,however,but to a limited'possibility space'.Suggestions for closing this'gulf of execution'were presented,including'voice control'and'hand-tracking',which are only feasible for this commercial product now with the availability of the Oculus Quest ***,wider implications for VR medical training were outlined,and potential next steps towards a standardized design identified.

关键词： Virtual reality Medical training Human-Centred design Interaction design

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

Final Cut Express HD 3.5 Editing Workshop 3

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