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Exploring Trends in Microcrack Properties of Sedimentary Rocks: An Audit of Dry and Water Saturated Sandstone Core Velocity–Stress Measurements

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International Journal of Geosciences 2012年第4期3卷 822-833页

作者： Doug A. Angus Quentin J. fisher James P. Verdon University of Bristol University of Leeds

Stress dependent rock physics models are being used more routinely to link mechanical deformation and stress perturbations to changes in seismic velocities and seismic anisotropy. In this paper, we invert for the effective non-linear microstructural parameters of 69 dry and saturated sandstone core samples. We evaluate the results in terms of the model input parameters of two non-linear rock physics models: A discrete and an analytic microstructural stress-dependent formulation. The results for the analytic model suggest that the global trend of the initial crack density is lower and initial aspect ratio is larger for the saturated samples compared to the corresponding dry samples. The initial aspect ratios for both the dry and saturated samples are tightly clustered between 0.0002 and 0.001, whereas the initial crack densities show more scatter. The results for the discrete model show higher crack densities for the saturated samples when compared to the corresponding dry samples. With increasing confining stress the crack densities decreases to almost identical values for both the dry and saturated samples. A key result of this paper is that there appears to be a stress dependence of the compliance ratio BN/BT within many of the samples, possibly related to changing microcrack geometry with increasing confining stress. Furthermore, although the compliance ratio BN/BT for dry samples shows a diffuse distribution between 0.4 and 2.0, for saturated samples the distribution is very tightly clustered around 0.5. As confining stresses increase the compliance ratio distributions for the dry and saturated samples become more diffuse but still noticeably different. This result is significant because it reaffirms previous observations that the compliance ratio can be used as an indicator of fluid content within cracks and fractures. From a practical perspective, an overarching purpose of this paper is to investigate the range of input parameters of the microstructural models

关键词： Compliance Ratio Microcrack Properties Saturated Stress Dependent Velocities Ultrasonic

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Prevalence of suicidal behavior following traumatic brain injury

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中华物理医学与康复杂志 2017年第3期39卷 210-210页

作者： fisher LB Pedrelli P Iverson GL

BACKGROUND AND OBJECTIVE Several studies have suggested that,following a traumatic brain injury(TBI),the risk of developing major depressive disorder is elevated,as compared with that of the general *** smaller,isolated studies have suggested an increased risk of suicide as *** study used the TBI Model Systems database(TBIMS)to better understand the rates of depression,

关键词：创伤性脑损伤自杀行为风险水平模型系统抑郁症总人口数据库

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Phosphorus Mass Balance of the Illinois River Watershed in Arkansas and Oklahoma

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Journal of Water Resource and Protection 2013年第6期5卷 591-603页

作者： Bernard Engel Meagan Smith John Berton fisher Roger Olsen Laurent Ahiablame Alexander Consulting 5802 South 129th East Avenue Tulsa USA CDM Inc. 1331 17th Street Denver USA Department of Agricultural and Biological Engineering Purdue University West Lafayette USA Lithochimeia Inc. 110 West 7th St. Tulsa USA

Water quality degradation in the Illinois River Watershed (IRW) has been linked to excess nutrients, primarily phosphorus (P). A mass balance study was performed on the IRW in Oklahoma and Arkansas to quantify the magnitude of P entering the watershed between the closure of Lake Tenkiller’s dam in 1954 to 2006. Results showed that a substantial mass of P was, and is, being imported into the watershed relative to the mass of P leaving the watershed. The study demonstrated that poultry production has been the major contributor of P imported to the watershed since 1964, and is currently responsible for more than 76% of the net annual P additions to the IRW. Between 1949 and 2002, more than 200,000 tonnes of P was added to the IRW. A P delivery ratio for the IRW was computed from the mass balance results and observed loads indicating that 4% of annual P applied to the IRW landscape reached Lake Tenkiller between 1999 and 2006. Allocation of P loads from 1949 to 2002 to Lake Tenkiller computed with the delivery ratio showed that wastewater treatment plant (WWTP) discharges were responsible for more than 50% of P reaching Lake Tenkiller in 1949, followed by dairy cattle (32% of loads). Poultry contribution to P reaching Lake Tenkiller was 5% in 1949 but increased rapidly to become the largest source in 1969 at approximately 49%, and in 2002 at 54%. Both dairy and WWTP portions of the loads declined from 1949 levels with less than 4% attributable to dairy and less than 34% assigned to WWTP in 2002.

关键词： Phosphorus Nonpoint Source Pollution Lake Watershed

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Signalized Corridor Timing Plan Change Assessment Using Connected Vehicle Data

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Journal of Transportation Technologies 2022年第3期12卷 310-322页

作者： Enrique Saldivar-Carranza Howell Li Jijo Mathew Charles fisher Darcy Michael Bullock Purdue University West Lafayette USA Ohio Department of Transportation Columbus USA

Updates to traffic signal timing plans are expected to either improve operations or mitigate the effects of increased volumes. Longitudinal before-after studies are important when validating changes to traffic signal systems, but they have historically required field data collection as well as deployment of extensive detection and communication equipment. These infrastructure-based techniques are costly and hard to scale. This study utilizes commercially available connected vehicle (CV) trajectory data to assess the change in performance between August 2020 and August 2021 on a 22-intersection corridor associated with the implementation of a semi-automated adaptive control system. Approximately 1 million trajectories and 13.5 million GPS points are analyzed for weekdays in August 2020 and August 2021. The vehicle trajectory data is used to compute corridor travel times and linear referenced relative to the far side of each intersection to generate Purdue Probe Diagrams (PPD). Using the PPDs, operational measurements such as arrivals on green (AOG), split failures (SF), and downstream blockage (DSB) are calculated. Additionally, traditional Highway Capacity Manual (HCM) level of service (LOS) is estimated. Even though there was a 35% increase in annual average daily traffic (AADT), the weighted average vehicle delay only increased by two seconds, LOS did not change, AOG improved by 1%, and SF and DSB remained the same. Based on the small changes in operational performance and considering the increase in traffic volume it is concluded that the implementation of the semi-automated adaptive control system had a significant positive impact in the corridor. The presented framework can be utilized by agencies to use CV data to perform before-after studies to evaluate the impact of signal timing plan changes. The presented methodology can be applied to any location where CV trajectory data is available.

关键词： Adaptive Control Traffic Signals Connected Vehicle Trajectories Perfor-mance Measures Before-After

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Influence of fibre and betaine on development of the gastrointestinal tract of broilers between hatch and 14 d of age

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Animal Nutrition 2019年第2期5卷 163-173页

作者： Tiago T.dos Santos Sthéfanie C.Dassi Celia R.C.Franco Cleber R.V.da Costa Sophie A.Lee Ana V.fisher da Silva Universidade Federal do Parana Curtiba81531-900Brazil Department of Cell Biology Universidade Federal do ParanaCuritiba81531-900Brazil AB Vista MarlboroughWiltshireSN8 4ANUnited Kindom Department of Cell Biology Universidade Federal do ParanaCuritiba81531-900Brazil

An experiment was designed to determine the influence of fibre and betaine on the development of the intestine, liver and pancreas of broilers from hatch to 14 d of age. A total of 250-day-old Cobb 500 male broilers were allocated to 16 cages with 15 broilers each. Treatments were arranged in a 2 x 4 factorial design, consisting of 2 feed formulations(low and high fibre diets) and 4 levels of betaine(0,1, 3 or 5 kg/t). At hatch, 10 birds in total were euthanised, and samples of the liver, pancreas, yolk sac and intestine were collected for reference of the analysed parameters before the start of the *** d 4.9 and 14, 5 birds per cage(10 birds per treatment) were selected, euthanised and treated as the same as the birds at hatch. Villus height and width and crypt depth were determined on the duodenum samples, and absorptive area was calculated. The number of enterocytes in mitosis at the villus was determined by a positive reaction to antibody for Ki67 protein, and fused villus was evaluated visually. The relative weight of the yolk sac reduced(P < 0.05) as birds aged while the intestine and liver reached a maximum(P < 0.05) at around d 4 and the pancreas at d 9. Birds fed the high fibre diet had greater feed intake, lower relative weight of the pancreas and higher villus(P < 0.05) than birds fed the low fibre diet. Villus width increased(P < 0.05) at 4 d of age, and this was associated with fused villus. Betaine inclusion reduced(P < 0.05) villus width, increased(P < 0.05) villus size and absorptive area, and reduced(P < 0.05) the number of enterocytes with positive reaction for the antibody *** inclusion reduced the width and increased the absorptive area and the villus height of the duodenum of birds up to 14 d of age. The higher fibre diet increased feed intake and villus height, yet reduced pancreas relative weight, while not affecting body weight gain. This response was possibly due to a dilution effect of the fibre, reducing nutrient absorption

关键词： Broiler Betaine Fibre Intestine maturation Pancreas Liver

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Racial disparity in years of potential life lost to induced abortions

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Open Journal of Preventive Medicine 2014年第1期4卷 8-12页

作者： James Studnicki Sharon J. MacKinnon John W. fisher Department of Public Health Sciences University of North Caro-lina at Charlotte Charlotte USA Doctoral Program in Health Services Research University of North Carolina at Charlotte Charlotte USA

The magnitude of the overall prevalence and racial disparity in induced abortion suggests that it is a major influence on the demographic and socioeconomic composition of the population of the United States (US). However, the years of potential lives averted by induced abortion have not been systematically studied. We applied race-specific intra-uterine death estimates to the induced abortions occurring to non-Hispanic (NH) white and non-Hispanic (NH) black women in the US state of North Carolina in 2008. The resultant estimate of births averted by induced abortion was used to project years of potential life lost. All-cause detailed mortality data were used to compare induced abortion with other contributing causes of years of potential life lost before age 75 (YPLL 75). For NH whites, induced abortions in 2008 contributed 59% of total YPLL 75, and 1.5 times the total YPLL 75 from all other causes combined. For NH blacks, induced abortions in 2008 contributed 76% of total YPLL 75 and 3.2 times the total YPLL 75 from all other causes combined. Induced abortion is the overwhelmingly predominant contributing cause of preventable potential lives lost in the North Carolina population, and NH blacks are disproportionately affected.

关键词： Abortion Years of Potential Life Lost

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Python Software Integrates with Microcontrollers and Electronic Hardware to Ease Development for Open-Source Research and Scientific Applications

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Advances in Internet of Things 2021年第1期11卷 42-58页

作者： Daniel K. fisher Reginald S. Fletcher Saseendran S. Anapalli United States Department of Agriculture Agricultural Research Service Sustainable Water Management Research Unit Stoneville Mississippi USA United States Department of Agriculture Agricultural Research Service Crop Production Systems Research Unit Stoneville Mississippi USA

Many options exist for developing and implementing monitoring systems for research and scientific applications. Commercially, available systems and devices, however, are usually built using proprietary tools and programming instructions, and often offer limited flexibility for end users. The use of open-source hardware and software has been embraced by the research and scientific communities and can be used to target unique data and information requirements. Development based on the Arduino microcontroller project has resulted in many successful applications, and the Arduino hardware and software environment continues to expand and become more powerful but can be intimidating for users with limited electronics or programming experience. The open-source Python language has gained in popularity and is being taught in schools and universities as an introduction to computer programming and software development due to its simple structure, ease of use, and large standard library of functions. A project called CircuitPython was developed to extend the use of Python to programming hardware devices such as programmable microcontrollers and maintains much of the original Python language and features, with additional support for accessing and controlling microcontroller hardware. The objective of the work reported here is to discuss the CircuitPython programming language and demonstrate its use in the development of research and scientific applications. Several open-source sensing and monitoring systems developed using open-source hardware and the open-source CircuitPython programming language are presented and described.

关键词： CircuitPython Python Arduino Agriculture Monitoring System Sensors

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越缠绵越健康越美丽

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现代保健 2004年第10期 74-75页

作者： fisher

饮食男女,人之大于存焉。祖国医学认为,如果没有正常和谐的性生活,会引起人们心理、生理的变异,导致女性内分泌紊乱和男性前列腺疾病的发生。

关键词：健康正常祖国医学性生活前列腺疾病内分泌紊乱饮食心理和谐生理

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血压怕高也怕低

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现代保健 2006年第2期 46-47页

作者： fisher

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Benchmarking the performance of Bayesian optimization across multiple experimental materials science domains

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npj Computational Materials 2021年第1期7卷 1742-1751页

作者： Qiaohao Liang Aldair E.Gongora Zekun Ren Armi Tiihonen Zhe Liu Shijing Sun James R.Deneault Daniil Bash Flore Mekki-Berrada Saif A.Khan Kedar Hippalgaonkar Benji Maruyama Keith A.Brown John fisher III Tonio Buonassisi Massachusetts Institute of Technology CambridgeMAUnited States Boston University BostonMAUnited States Singapore-MIT Alliance for Research and Technology SingaporeSingapore Air Force Research Laboratory DaytonOhioUnited States Agency for Science Technology and Research(A*STAR)SingaporeSingapore National University of Singapore SingaporeSingapore Present address:Aalto University EspooFinland Present address:Northwestern Polytechincal University(NPU) Xi’anShaanxi P.R.China

Bayesian optimization(BO)has been leveraged for guiding autonomous and high-throughput experiments in materials ***,few have evaluated the efficiency of BO across a broad range of experimental materials *** this work,we quantify the performance of BO with a collection of surrogate model and acquisition function pairs across five diverse experimental materials *** defining acceleration and enhancement metrics for materials optimization objectives,we find that surrogate models such as Gaussian Process(GP)with anisotropic kernels and Random Forest(RF)have comparable performance in BO,and both outperform the commonly used GP with isotropic *** with anisotropic kernels has demonstrated the most robustness,yet RF is a close alternative and warrants more consideration because it is free from distribution assumptions,has smaller time complexity,and requires less effort in initial hyperparameter *** also raise awareness about the benefits of using GP with anisotropic kernels in future materials optimization campaigns.

关键词： optimization performance acceleration

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