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| 1 | Slope reliability and back analysis of failure with geotechnical parameters estimated using Bayesian inference显示文摘A Bayesian approach is proposed for the inference of the geotechnical parameters used in slope design.The methodology involves the construction of posterior probability distributions that combine prior information on the parameter values with typical data from laboratory tests and site investigations used in design.The posterior distributions are often complex,multidimensional functions whose analysis requires the use of Markov chain Monte Carlo(MCMC)methods.These procedures are used to draw representative samples of the parameters investigated,providing information on their best estimate values,variability and correlations.The paper describes the methodology to define the posterior distributions of the input parameters for slope design and the use of these results for evaluation of the reliability of a slope with the first order reliability method(FORM).The reliability analysis corresponds to a forward stability analysis of the slope where the factor of safety(FS)is calculated with a surrogate model from the more likely values of the input parameters.The Bayesian model is also used to update the estimation of the input parameters based on the back analysis of slope failure.In this case,the condition FS?1 is treated as a data point that is compared with the model prediction of FS.The analysis requires a sufficient number of observations of failure to outbalance the effect of the initial input parameters.The parameters are updated according to their uncertainty,which is determined by the amount of data supporting them.The methodology is illustrated with an example of a rock slope characterised with a Hoek-Brown rock mass strength.The example is used to highlight the advantages of using Bayesian methods for the slope reliability analysis and to show the effects of data support on the results of the updating process from back analysis of failure. | Luis-Fernando Contreras Edwin T.Brown | 2019 | Journal of Rock Mechanics and Geotechnical Engineering2019，11，3： | 7 |
| 2 | 草甘膦对可食用蓝藻葛仙米生长和生理的影响(英文)显示文摘葛仙米(N.sphaeroides)的产量和产地面积逐年减少,这可能与当地广泛使用除草剂草甘膦有关。为此,本文测定了不同浓度(0.15、0.30、0.45、0.6mmol/L)的草甘膦处理的葛仙米的颗粒大小、干重、叶绿素荧光、叶绿素浓度。所有测量参数与浓度和时间显著相关:0.15mmol/L处理组的颗粒直径较对照组小15%(2d后);叶绿素a浓度和最大量子产率(Fv/Fm)在最高浓度组(0.6mmol/L)4d后开始受到影响;第8天,相对生长速率(以干重计算,大于0.15mmol/L)、光合作用活性(大于0.3mmol/L)均受显著抑制,其中0.15mmol/L处理组相对生长下降60%,而更高浓度处理组出现负生长,0.6mmol/L组藻体漂白死亡。结合实验结果,文章讨论了草甘膦的毒性机理及其对葛仙米(N.sphaeroides)的潜在影响。 | 阮祚禧 Murray T.Brown | 2008 | 水生生物学报2008，32，4： | 6 |
| 3 | Bayesian data analysis to quantify the uncertainty of intact rock strength显示文摘One of the main difficulties in the geotechnical design process lies in dealing with uncertainty. Uncertainty is associated with natural variation of properties, and the imprecision and unpredictability caused by insufficient information on parameters or models. Probabilistic methods are normally used to quantify uncertainty. However, the frequentist approach commonly used for this purpose has some drawbacks.First, it lacks a formal framework for incorporating knowledge not represented by data. Second, it has limitations in providing a proper measure of the confidence of parameters inferred from data. The Bayesian approach offers a better framework for treating uncertainty in geotechnical design. The advantages of the Bayesian approach for uncertainty quantification are highlighted in this paper with the Bayesian regression analysis of laboratory test data to infer the intact rock strength parameters σ_(ci) and m_i used in the Hoek-Brown strength criterion. Two case examples are used to illustrate different aspects of the Bayesian methodology and to contrast the approach with a frequentist approach represented by the nonlinear least squares(NLLS) method. The paper discusses the use of a Student's t-distribution versus a normal distribution to handle outliers, the consideration of absolute versus relative residuals, and the comparison of quality of fitting results based on standard errors and Bayes factors. Uncertainty quantification with confidence and prediction intervals of the frequentist approach is compared with that based on scatter plots and bands of fitted envelopes of the Bayesian approach. Finally, the Bayesian method is extended to consider two improvements of the fitting analysis. The first is the case in which the Hoek-Brown parameter, a, is treated as a variable to improve the fitting in the triaxial region. The second is the incorporation of the uncertainty in the estimation of the direct tensile strength from Brazilian test results within the overall evaluation of the intact rock strength. | Luis Fernando Contreras Edwin T.Brown Marc Ruest | 2018 | Journal of Rock Mechanics and Geotechnical Engineering2018，10，1： | 4 |
| 4 | Treatment of metastatic sarcoma to the liver with bland embolization显示文摘 | Mary A.Maluccio Anne M.Covey JohannaSchubert Lynn A.Brody Constantinos T.Sofocleous George I.Getrajdman RonaldDeMatteo Karen T.Brown | 2006 | Cancer2006，，7： | 1 |
| 5 | Prospective evaluation of ^(18)F-FDG positron emission tomography in the preoperative staging of patients with hepatic colorectal metastases显示文摘Background:Despite considerable advances in preoperative imaging,up to one-third of patients operatively explored for hepatic colorectal metastases are unexpectedly found to harbor unresectable intrahepatic or extrahepatic disease.Methods:The current study is a prospective,blinded study comparing utility of[18F]2-fluoro-2-deoxyglucose positron emission tomography(18F-FDG-PET)to computed tomography(CT)and CT arterial portography(CTAP)as preoperative staging.Results:The 125 planned subjects were enrolled.Findings seen on FDG-PET alone changed therapy for 23 of 125 patients(18%).FDG-PET confirmed other radiologic findings in 16 cases(13%),for an overall influence on therapy in 39 cases(31%).FDG-PET was the most sensitive diagnostic imaging test for extrahepatic cancer;it was 80-90%sensitive for extrahepatic cancer and 70-90%specific.For the 28 cases of unresectable disease due to extrahepatic disease,FDG-PET findings solely changed therapies in 16 cases(57%)and influenced therapy in seven other cases(25%).Of the 21 unresectable cases due to extent of intrahepatic disease,FDG-PET did not solely change therapy in any.Overall,FDG-PET had the lowest sensitivity for hepatic sites compared with CT or CTAP.In particular,small(<1 cm)liver tumors were particularly poorly detected by FDG-PET.The area under the receiver operating characteristic(ROC)curve for small tumors was 0.58 and for patients on chemotherapy it was 0.66,a modest improvement over no imaging.Conclusions:FDG-PET is an important test for preoperative staging of patients with hepatic colorectal metastases,affecting treatment decisions in nearly one-third of patients.The high yield is due mainly to detection of extrahepatic disease.It is therefore recommended in patients with extrahepatic lesions suspected to be disseminated cancer or those with high risk for extrahepatic disease.It is not a good test for identification of small tumors in the liver. | Tim Akhurst Mithat Gönen Raymond E.Baser Lawrence H.Schwartz Scott Tuorto Lynn A.Brody Anne Covey Karen T.Brown Steven M.Larson Yuman Fong | 2022 | Hepatobiliary Surgery and Nutrition2022，11，4： | 1 |
| 6 | Theory and Evidence on Resolution of Financial Distress显示文摘 | David T.Brown Brian A.Cichetti Timothy J.Riddiough | | 0，，04： | 1 |
| 7 | Graphene-Enhanced Fracture Resistance of Epoxy Nanocomposites for Structural Applications显示文摘The fracture characteristics of graphene nano-platelets(GNP)in epoxy composite under high strain loadings were investigated using impact test at room temperature.The energy required to create a new surface was measured with load cell and the accompanied plain strain fracture toughness was calculated.The investigation covered the effect of the amount of graphene in graphene/epoxy composite material system on the fracture behavior of the material.The results showed that both the manufacturing and experimental procedures developed were excellent to quickly and precisely characterize the response of GNP/epoxy composite to impact loadings.Furthermore,the results showed clear dependencies of the material response on the amount of GNP in epoxy. | O.Aluko M.Vaziri T.Brown G.Knowles | 2020 | Journal of Mechanics Engineering and Automation2020，10，5： | 0 |
| 8 | Experimental Analysis of Epoxy and Graphene Nanoplatelet/Epoxy Composites显示文摘The tensile behavior of graphene nanoplatelets(GNPs)in epoxy composite under tensile loadings was characterized using uniaxial tensile test at various strain rates ranging from 0.0356 to 0.14/min at room temperature.The stresses and the accompanied strains were measured with load cell and an extensometer,respectively.This investigation covers the effect of the amount of graphene in graphene/epoxy composite material system.The uniaxial tensile tests were done to investigate the tensile behavior of the material beyond ultimate tensile strength.The results showed that both the manufacturing and experimental procedure developed are excellent methods to characterize the response of GNP/epoxy composite to tensile loadings.Additionally,the results show a clear strain rate and amount of GNP in epoxy dependencies in the material response. | Z.Broughman N.Park,T.Brown O.Aluko M.Vaziri | 2019 | Journal of Mechanics Engineering and Automation2019，9，2： | 0 |
| 9 | 《可摘局部义齿修复学》显示文摘 | Alan B.Carr Glen P.McGivney David T.Brown 张富强(主译) | 2008 | 实用口腔医学杂志2008，24，1： | 0 |
| 10 | Transcranial electrical stimulation in neurological disease显示文摘Increased lifespan is one of society’s greatest achievements,but this longevity increases the prevalence of diseases of aging,such as neurological disorders.Globally,neurological disorders are the leading cause of disability and the second leading cause of deaths(Feigin et al.,2019).Furthermore,these diseases affect people in low-,medium-,and high-income countries(Feigin et al.,2019).Current technology to modify neurological burden is scarce,which poses numerous challenges for healthcare,global policy,and economic stability(Feigin et al.,2019).To face these challenges,brain stimulation technology,such as transcranial electrical stimulation(TES),has displayed exciting potential.Antal et al.(2017)provide a detailed overview of the safety and application of TES.Commonly,electrodes are attached to the head and a weak current(e.g.,1-2 mA)is applied through the scalp,skull,and into the brain for 10-30 minutes to activate neurons(Antal et al.,2017).The technique is extremely safe with no serious adverse effects reported from thousands of sessions(Antal et al.,2017).The most common side effects are a tingling/itching sensation or redness at the stimulation site(Antal et al.,2017).However,these side effects can be minimized by reducing the electrode-skin impedance,slowly ramping up and ramping down TES,or using topical analgesics(Antal et al.,2017).The development of TES may repair neural dysfunction and stem the oncoming incidence of neurodegenerative disease. | Gregory L.Brown Michael T.Brown | 2022 | Neural Regeneration Research2022，17，10： | 0 |
| 11 | Appraising the Challenge of Reconstructing“Peace”and“Justice”in Post-conflict African States显示文摘Examination of the complexities that countries emerging from authoritarian regimes and civil wars face is timely.Given the extensive physical infrastructure devastation that occurs during conflicts in organised societies,the restoration of peace and justice must be given priority.This study explores the substantial impact of these conflicts on how people perceive and value justice and peace,especially in pluralistic societies where different cultural orientations lead to different points of view.Defining an objective and widely recognised notion of“justice”is difficult when conflicts are associated with ethnic,religious,or economic interests.This complexity is increased in such instances.For post-conflict administrations seeking to reconstruct destroyed state and institutional structures,this problem presents serious challenges.The interpretational biases brought about by the ethnic backgrounds of newly elected political leaders result in perceived favouritism and the marginalisation of minority communities.Furthermore,the efficacy of post-conflict administrations is hampered by ethnic heterogeneity and religious divisions,necessitating a review and reconstruction of constitutional mechanisms for justice and peace.Rebuilding post-conflict communities entails not only the physical infrastructure but also the reestablishment of justice norms.This is especially difficult in Africa because of the continent’s low level of infrastructure development and the complexity of the political,ethnic,religious,and social issues at play.To tackle these problems,legal norms must be followed,communication must be opened,and steps to foster trust amongst ethnic groups must be taken.To secure sustained peace and development,successful restoration requires a careful balancing act between national institutions and international partnerships,with a focus on local ownership.The paper takes a close look at these issues and poses important queries on the best strategies for maintaining growth and stability in transitional regimes.An analysis of social dynamics in post-conflict settings provides a basis for recommending workable solutions to African states facing comparable challenges. | Nlerum S.Okogbule Cleverline T.Brown | 2024 | US-China Law Review2024，21，1： | 0 |
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