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why ecosystem characteristics predicted from remotely sensed data are unbiased and biased at the same time-and how this affects applications

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Forest Ecosystems 2024年第1期11卷 24-31页

作者： Goran Ståhl Terje Gobakken Svetlana Saarela Henrik J.Persson Magnus Ekstrom Sean P.Healey Zhiqiang Yang Johan Holmgren Eva Lindberg Kenneth Nystrom Emanuele Papucci Patrik Ulvdal Hans OleØrka Erik Næsset Zhengyang Hou Håkan Olsson ronald E.McRoberts Department of Forest Resource Management Swedish University of Agricultural Sciences90183UmeåSweden Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life SciencesÅsNorway USDA Forest Service Rocky Mountain Research StationOgdenUTUSA The Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing100083China Department of Forest Resources University of MinnesotaSt.PaulMNUSA

Remotely sensed data are frequently used for predicting and mapping ecosystem characteristics,and spatially explicit wall-to-wall information is sometimes proposed as the best possible source of information for ***,wall-to-wall information typically relies on model-based prediction,and several features of model-based prediction should be understood before extensively relying on this type of *** such feature is that model-based predictors can be considered both unbiased and biased at the same time,which has important implications in several areas of *** this discussion paper,we first describe the conventional model-unbiasedness paradigm that underpins most prediction techniques using remotely sensed(or other)auxiliary *** this point of view,model-based predictors are typically ***,we show that for specific domains,identified based on their true values,the same model-based predictors can be considered biased,and sometimes severely *** suggest distinguishing between conventional model-bias,defined in the statistical literature as the difference between the expected value of a predictor and the expected value of the quantity being predicted,and design-bias of model-based estimators,defined as the difference between the expected value of a model-based estimator and the true value of the quantity being *** show that model-based estimators(or predictors)are typically design-biased,and that there is a trend in the design-bias from overestimating small true values to underestimating large true ***,we give examples of applications where this is important to acknowledge and to potentially make adjustments to correct for the design-bias *** argue that relying entirely on conventional model-unbiasedness may lead to mistakes in several areas of application that use predictions from remotely sensed data.

关键词： Bias Model-based inference Design-based inference

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Hepatocellular carcinoma: Advances in diagnosis, management, and long term outcome

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world Journal of Hepatology 2015年第9期7卷 1157-1167页

作者： Adam S Bodzin ronald w.busuttil Department of Surgery University of California

Hepatocellular carcinoma(HCC) remains a common and lethal malignancy worldwide and arises in the setting of a host of diseases. The incidence continues to increase despite multiple vaccines and therapies for viruses such as the hepatitis B and C viruses. In addition, due to the growing incidence of obesity in western society, there is anticipation that there will be a growing population with HCC due to non-alcoholic fatty liver disease. Due to the growing frequency of this disease, screening is recommended using ultrasound with further imaging using magnetic resonance imaging and multi-detector computed tomography used for further characterization of masses. Great advances have been made to help with the early diagnosis of small lesions leading to potential curative resection or transplantation. Resection and transplantation maybe used in a variety of patients that are carefully selected based on underlying liver disease. Using certain guidelines and clinical acumen patients may have good outcomes with either resection or transplantation however many patients are inoperable at time of presentation. Fortunately, the use of new locoregional therapies has made down staging patients a potential option making them potential surgical candidates. Despite a growing population with HCC, new advances in viral therapies, chemotherapeutics, and an expanding population of surgical and transplant candidates might all contribute to improved long-term survival of these patients.

关键词： Hepatocellular carcinoma Transplantation Survival Locoregional therapy Resection

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Finite Complements in English

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外国语 2008年第1期31卷 2-35页

作者： ronald w. Langacker University of California San Diego USA

This paper explores the conceptual basis of finite complementation in English. It first considers the distinguishing property of a finite clause,namely grounding,effected by tense and the modals. Notions crucial for clausal grounding—including a reality conception and the striving for control at the effective and epistemic levels—also figure in the semantic import of complementation. An essential feature of complement constructions is the involvement of multiple conceptualizers,each with their own conception of reality. The different types of complement and their grammatical markings can be characterized on this basis. Finite complements differ from other types by virtue of expressing an autonomous proposition capable of being apprehended by multiple conceptualizers,each from their own vantage point. A cognitive model representing phases in the striving for epistemic control provides a partial basis for the semantic description of predicates taking finite complements. The same model supports the description of both personal and impersonal complement constructions.

关键词：英语认知文法补语谓词限定从句

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Access,Activation,and Overlap:Focusing on the Differential

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外国语 2012年第1期35卷 2-25页

作者： ronald w.Langacker University of California San DiegoU.S.A.

As a long term goal,Cognitive Grammar envisages a unified account of linguistic structure,processing,and discourse.A key requirement is that it properly reflect the dynamicity of language,in all its aspects(including grammar).Consisting as it does in patterns of activity,language is something that happens: it unfolds through time,and how it does so is essential for its *** structure involves the complex interplay of serial and hierarchical *** theory has generally overemphasized the latter,as witnessed by the predominant role of grammatical constituency based on the metaphor of composition("building" a complex structure out of smaller "pieces").More promising for a unified treatment of structure,processing,and discourse is an alternative metaphor,in which a "moving window" of attention allows serial access to complex conceptions that are mostly already in *** processing proceeds concurrently on different time scales,in windows of different *** provides a dynamic basis for hierarchical *** arises when conceptions accessed in windows on one time scale figure in a distinct and more elaborate conception(with its own,emergent properties) accessed in a single window on a larger time *** on the alternative metaphor,an approach is outlined that features serial access,windows of attention,levels of activation,and conceptual *** is then applied,in exploratory fashion,to a number of grammatical *** "access-and-activation" approach directly accommodates reference point relationships,the basis for possessive and topic *** lends itself quite well to the characterization of informational focus,marked in English by unreduced *** requisite descriptive notions are then extended and adapted for ellipsis,which has rather different *** same notions prove useful for handling problematic aspects of coordinate ***,they provide a straig

关键词： attention conceptual overlap discourse dynamicity seriality vs.hierarchy

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Metonymy in Grammar

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外国语 2004年第6期27卷 2-24页

作者： ronald w.Langacker UniversityofCalifornia

An assumption usually made in syntactic theory and description is that particular elements combine with one another in very specific and determinate ways. Syntactically, for example, the sentence Alice likes Bill involves a specific structural configuration, with the elements Alice, likes, and Bill inserted in particular slots. Semantically, the predicate LIKE has two arguments, which ALICE and BILL instantiate in accordance with their syntactic roles.

关键词：转喻语法造句法语句构成修辞方法英语

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ERROR REDUCTION IN ADAPTIVE FINITE ELEMENT APPROXIMATIONS OF ELLIPTIC OBSTACLE PROBLEMS

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Journal of Computational Mathematics 2009年第2期27卷 148-169页

作者： Dietrich Braess Carsten Carstensen ronald H.w.Hoppe Faculty of Mathematics Ruhr University BochumD-44780 BochumGermany Institute of Mathematics Humboldt University of BerlinD-10099 BerlinGermany Department of Mathematics University of HoustonHoustonTX 77204-3008USA Institute of Mathematics University at AugsburgD-86159 AugsburgGermany

we consider an adaptive finite element method （AFEM） for obstacle problems associated with linear second order elliptic boundary value problems and prove a reduction in the energy norm of the discretization error which leads to R-linear convergence. This result is shown to hold up to a consistency error due to the extension of the discrete multipliers （point functionals） to H^-1 and a possible mismatch between the continuous and discrete coincidence and noncoincidence sets. The AFEM is based on a residual-type error estimator consisting of element and edge residuals. The a posteriori error analysis reveals that the significant difference to the unconstrained case lies in the fact that these residuals only have to be taken into account within the discrete noncoincidence set. The proof of the error reduction property uses the reliability and the discrete local efficiency of the estimator as well as a perturbed Galerkin orthogonality. Numerical results are given illustrating the performance of the AFEM.

关键词： Adaptive finite element methods Elliptic obstacle problems Convergence analysis

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EFFECTS OF RIVER ICE ON STAGE-DISCHARGE RELATIONSHIPS——A CASE STUDY OF THE YELLOw RIVER

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International Journal of Sediment Research 2007年第4期22卷 263-272页

作者： ronald THRING Bryan w. KARNEY Prof. Environmental Engineering University of Northern British Columbia 3333 University Way Prince George BC Canada V2N 4Z9 Prof. Department of Civil Engineering University of Toronto 35 St. George Street Toronto ON Canada M5S 1A4

Using field observations at four gauging stations along the Inner Mongolia Reach of the Yellow River in China, this paper explores effects of the ice on the hydraulics of this river reach for four different conditions, namely: under open channel flow, during ice-running period, the ice-covered period, and the river break-up period. The rating curves were found to be well recognized under open channel situations, but were sometimes poorly defined and extremely variable under ice conditions. The results also show that the water level is insensitive to flowing ice prior to freeze-up. However, significant, but hardly surprising, variations were observed during ice-covered conditions. The rating curves for both the ice covered condition and river ice breakup period are developed and some related hydraulic issues are examined. Additionally, the impacts of the ice accumulation and associated riverbed deformation during ice period on the rating curves are discussed.

关键词： Ice-running period Ice covered period Rating curve Riverbed deformation River ice break-up

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wEAK-DUALITY BASED ADAPTIVE FINITE ELEMENT METHODS FOR PDE-CONSTRAINED OPTIMIZATION wITH POINTwISE GRADIENT STATE-CONSTRAINTS

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Journal of Computational Mathematics 2012年第2期30卷 101-123页

作者： M. Hintermuer Michael Hinze ronald H.w. Hoppe Department of Mathematics Humboldt-University of Berlin Germany Department of Mathematics University of Hamburg Germany Department of Mathematics University of Augsburg Germany and Department of MathematicsUniversity of Houston USA

Adaptive finite element methods for optimization problems for second order linear el- liptic partial differential equations subject to pointwise constraints on the l2-norm of the gradient of the state are considered. In a weak duality setting, i.e. without assuming a constraint qualification such as the existence of a Slater point, residual based a posteriori error estimators are derived. To overcome the lack in constraint qualification on the continuous level, the weak Fenchel dual is utilized. Several numerical tests illustrate the performance of the proposed error *** subject classification： 65N30, 90C46, 65N50, 49K20, 49N15, 65K10.

关键词： Adaptive finite element method A posteriori errors Dualization Low regu-larity Pointwise gradient constraints State constraints weak solutions.

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Minimum spouting velocity of flat-base spouted fluid bed

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Particuology 2018年第1期16卷 27-36页

作者： Esmail R. Monazam ronald w. Breault Justin weber Ky Layfield National Energy Technology Laboratory U. S. Department of Energy 3610 Collins Ferry Rd. Morgantown WV26507-0880 USA REM Engineering Services PLLC 3537 Collins Ferry Rd. Morgantown WV26505 USA

Experiments were performed on spout characteristics of a cylindrical spout-fluidized bed （I.D. = 10 cm） with different static heights and two materials （A1203 and high density polyethylene）. Results of minimum spouting velocity obtained in this study were compared with reported correlations for both spouted and spout-fluidized beds. Considerable discrepancies were found between the values obtained using different model equations as well as with respect to experimental results. Based on the Mathur-Gishler correlation, a new correlation is proposed for calculating the minimum spouting velocity that introduces the ratio U/Umf. It was found that the minimum spouting velocity decreases with increasing fluidizing gas velocity （U/Umf）. The pressure drop at the point of minimum spouting velocity is also correlated using this dimensionless group and is presented in this work. This investigation demonstrates that the use of correlations reported in the literature that focus primarily on conical bottom spouted beds are not applicable to fiat-bottom spouted and spout-fluidized beds.

关键词： Spouted bed Spout-fluidized bed Minimum spouting velocity Flat-bottom spouted bed

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Functional Outcomes of Adult Tibia Shaft Fractures Treated with Solid Intramedullary Nails versus Hollow Nails: A Systematic Review

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Open Journal of Orthopedics 2024年第3期14卷 149-172页

作者： Kwadwo Aning Abu Bernard Hammond Mohammed Issah Suglo Bukari Kizito Kakra Vormawor ronald Awoonor-williams David Anyitey-Kokor Paa Kwesi Baidoo Dominic Konadu-Yeboah Department of Orthopaedics St. John of God Hospital Duayaw Nkwanta Ghana Directorate of Trauma and Orthopaedics Komfo Anokye Teaching Hospital Kumasi Ghana Department of Surgery Tamale Teaching Hospital Tamale Ghana Department of Orthopadics and Trauma Seventh Day Adventist Hospital Asamang Ghana

Introduction: The management of fractures of the tibia shaft is an important aspect of orthopaedic care, and the selection of the surgical method for fixation can substantially impact patient outcomes. The current review aims to compare the outcomes of adult tibia fractures treated with solid nails to those treated with hollow nails. Methods: A search on Scopus, PubMed, and Cochrane Library, using three keywords (Outcome, Tibia shaft fractures, Nail) was conducted in April 2023. Results were compiled and two independent reviewers screened and selected eligible articles After removing duplicates, titles and abstracts were read to exclude ineligible studies. Full-text articles of the remaining papers were read to select eligible studies which were further critically appraised to ascertain their methodological quality. The data extracted from the selected papers were synthesized using a combination of pooling of results, tests of statistical difference (t-test and chi-square) and narrative synthesis methods. Results: A total of 2295 articles were obtained from the databases and citation searching. A total of 9 papers were identified as eligible and included in the review. Findings revealed that there is no statistical difference in the outcomes of tibia fractures treated with either solid or hollow nail groups such as duration of surgery (p = 0.541), rate of delayed and non-union (p = 0.342), and rate of surgical site infections (p = 0.395). Conclusion: Intramedullary nailing of tibia shaft fractures with either solid or hollow nails have similar functional outcomes.

关键词： Tibia Shaft Fractures Functional Outcome SIGN Nail Hollow Nail

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