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Correlating Connected Vehicle Estimated Deceleration Events with Crash Incidents near Interstate Interchanges

Journal of Transportation Technologies 2023年第4期13卷 674-688页

作者： Jairaj Desai Jijo K. mathew Howell Li justin mukai Rahul Suryakant Sakhare Darcy m. Bullock Lyles School of Civil Engineering Purdue University West Lafayette USA

Historical roadway safety analyses have used labor and time-intensive crash data collection procedures. However, crash reporting is often delayed and crash locations are reported with varying levels of spatial accuracy and detail. Recent advances in connected vehicle (CV) data provide an opportunity for stakeholders to proactively identify areas of safety concerns in near-real time with high spatial precision. Public and private sector stakeholders including automotive original equipment manufacturers (OEm) and insurance providers may independently define acceleration thresholds for reporting unsafe driver behavior. Although some OEms have provided fixed threshold hard-braking event data for a number of years, this varies by OEm and there is no published literature on the best thresholds to use for identifying emerging safety issues. This research proposes a methodology to estimate deceleration events from raw CV trajectory data at varying thresholds that can be scaled to any CV. The estimated deceleration events and crash incident records around 629 interstate exits in Indiana were analyzed for a three-month period from march 1-may 31, 2023. Nearly 20 million estimated deceleration events and 4800 crash records were spatially joined to a 2-mile search radius around each exit ramp. Results showed that deceleration events between -0.5 g and -0.4 g had the highest correlation with an R2 of 0.69. This study also identifies the top 20 interstate exit locations with highest deceleration events. The framework presented in this study enables agencies and transportation professionals to perform safety evaluations on raw trajectory data without the need to integrate external data sources.

关键词： Connected Vehicles Hard-Braking Crashes Safety Deceleration

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Analysis of Flow Dynamics in the High-Flux Gas-Solid Riser Using Trajectory Distances across Attractors Reconstructed from Solid Concentration Signals

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Engineering（科研） 2018年第10期10卷 688-703页

作者： justin m. Jeremiah Samwel V. manyele Abraham K. Temu Jesse-X. Zhu Department of Chemical and mining Engineering University of Dar es Salaam Dar es Salaam Tanzania Department of Chemical and Biochemical Engineering University of Western Ontario London ON Canada

The study of the entrance and wall dynamics of a high-flux gas-solid riser was conducted using trajectory distances of the reconstructed attractors from solid concentration signals collected from a 76 mm internal diameters and 10 m high riser of a circulating fluidized bed (CFB) system. The riser was operated at 4.0 to 10.0 m/s gas velocity and 50 to 550 kg/m2s solids flux. Spent fluid catalytic cracking (FCC) catalyst particles with 67 μm mean diameter and density of 1500 kg/m3 together with 70% to 80% humid air was used. Solid concentration data were analyzed using codes prepared in FORTRAN 2008 to get trajectories of the reconstructed attractors and their distances apart. Trajectory distances were found to increase from the centre towards the wall indicating the expansion of the attractor. The probability density function (PDF) of the trajectory distances changes from single peak at the centre to multiple peaked profiles in the wall region. multiple peaked profiles indicate multifractal flow behaviours. Cumulative distribution functions (CDF) of the trajectory distances changes from single S-shaped at the centre to multiple S-shaped profiles in some locations of the wall region indicating multifractal flow behaviours. The PDF distribution of these distances at the entrance section and in the wall region forms different types of statistical distributions showing differences in gas-solid flow structures in various spatial locations of the wall region and the entrance sections. most of the distributions at the centre fall under the Gumbel max distribution for all flow development sections of the riser, especially at air velocities of 5.5 m/s and 8 m/s showing uniform flow structures. Further, it was found that increase of the number of the phase space reconstruction embedding dimension increases the trajectory distances between the state vectors leading to the expansion of the attractor.

关键词： Trajectory Distance Probability Density Function Cumulative Distribution Function Euclidian Distance High-Flux Riser

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广州市社区人群流感抗体水平与人际接触状况的相关性分析

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中华流行病学杂志 2014年第4期35卷 433-436页

作者：郭健安江朝强谭丽究 justin Lessler Jonathan m.Read 朱华晨管轶 Derek AT.Cummings S.Riley 香港大学公共卫生学院广州市第十二人民医院美国约翰霍普金斯大学公共卫生学院英国利物浦大学汕头大学医学院英国帝国学院公共卫生学院

目的探讨广州市社区人群流感抗体水平与人际接触状况的相关性.方法采用Google数码地图随机抽取广州市行政区域范围内研究点,受检者接受问卷调查并抽取静脉血检测甲型流感（H3N2、H1Nl）抗体.结果（1）Google数码地图随机选取50个点... 详细信息

目的探讨广州市社区人群流感抗体水平与人际接触状况的相关性.方法采用Google数码地图随机抽取广州市行政区域范围内研究点,受检者接受问卷调查并抽取静脉血检测甲型流感（H3N2、H1Nl）抗体.结果（1）Google数码地图随机选取50个点中符合研究入选条件40个（856户家庭2 801人）作为研究对象,实际参加1 821人（65.0％）,乡村和市区人群分别占77.3％（1 407/1 821）和22.7％（414/1 821）,以18～59岁年龄段为主,其次为≥60岁老年人,2～17岁组比例最低;（2）愿意提供血样者占78.1％（1 423/1 821）,H3N2和H1N1流感病毒抗体阳性率与年龄密切相关,以2～17岁年龄组最高;（3）受检人群间皮肤或近距离人际接触频率甚高,每天接触≥10人者高达49.8％～ 72.6％,无零接触者,且以6～17岁组比例最高;相对于工作日,休息日接触人数较少.结论广州地区社区人群H3N2和H1N1流感病毒抗体阳性率以及人际间近距离接触频率均与年龄有关.

关键词：流感抗体水平社区人群人际接触

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Investigation of Entrance and Wall Dynamics of the High-Flux Gas-Solid Riser Using Statistical Analysis of Solids Concentration Signals

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Engineering（科研） 2019年第3期11卷 167-187页

Statistical analysis of the entrance and wall dynamics of a high-flux gas-solid riser was done using solid concentration time series data collected from a 76 mm internal diameter and 10 m high riser of a CFB system with a twin-riser operated at 4.0 to 10.0 m/s gas velocity and 50 to 550 kg/m2s solids flux. Spent fluid catalytic cracking catalyst particles with 67 μm mean diameter and density of 1500 kg/m3 together with 70% to 80% humid air was used. Solid concentration data were analysed using code prepared using FORTRAN 2008 to get statistical parameters and plot their profiles. Results obtained show that the gas-solid suspension flow in the riser is dominated by low solid concentration in the centre region and high solid concentration in the wall region which forms a core-annulus flow structure. The mean solid concentration in the wall region decreases with riser height from the dense bottom section to less dense in the fully developed flow section at the top of the riser. The gas-solid suspension flow in the centre region is dominated with uniform flow structure while the wall region is dominated with high fluctuations in solid concentration. Further, it was found that the entrance and developing flow sections of the riser exhibit high flow non-uniformities than the fully developed flow section of the riser. The flow non-uniformities in the entrance and developing flow section increase with increase in superficial gas velocity at constant solid flux. The wall region, from the entrance to the top sections of the riser along the axial direction exhibits both dilute and dense suspension flow.

关键词： Entrance Section Wall Region Statistical Analysis Flow Non-Uniformities Radial Non-Uniformity Index

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Evaluation of Organic Acid-Based Sanitizers for Reduction of <i>Escherichia coli</i>O157:H7 during Flume-Washing of Organic Leafy Greens

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Food and Nutrition Sciences 2017年第10期8卷 946-960页

作者： Pushpinder Kaur Litt justin Brooks Divya Jaroni Dept. of Animal Science and Robert m. Kerr Food and Agricultural Products Center Oklahoma State University Stillwater Oklahoma USA

Antimicrobial efficacy of three novel organic sanitizers, CHICO WashTm, C8C10 and CG100, was evaluated for the reduction of Escherichia coli O157:H7 during flume-washing of organic leafy greens. Organic formulations at various concentrations: CHICO (C3H8I0C3O7) WashTm (1:20 ratio) and C8C10 and CG100 (0.2 and 0.4%), along with the controls: hydrogen-peroxide and water, were used for washing organic baby and mature spinach and romaine and iceberg lettuce. Leafy greens were inoculated with a 2-strain cocktail of E. coli O157:H7 (6 logs CFU/mL) and washed in each treatment for 1 or 2 minutes. The treated leafy greens were stored at 4°C and surviving pathogen populations determined on days 0, 1, and 3 of storage. Organic sanitizers, for both treatment times, significantly (P E. coli O157:H7 on all the leafy greens during storage. Highest reduction (3.4 logs CFU/g) was observed after treatment with CG100 (0.4%) in romaine lettuce, while CHICO WashTm showed greater than 2 logs CFU/g reduction on all the leafy greens, by day 3. This study demonstrates the potential application of organic sanitizers in flume-washing of organic leafy greens for the reduction of E. coli O157:H7.

关键词： Organic Sanitizers Escherichia coli O157:H7 Organic Leafy Greens Antimicrobials

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mapping Correlation Dimension along the Wall Region of a High-Flux Gas-Solid Riser Using Embedded Solid Concentration Time Series

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Engineering（科研） 2018年第10期10卷 655-679页

Analysis of the entrance and wall dynamics of a high-flux gas-solid riser was conducted using embedded solid concentration time series collected from a 76 mm internal diameter and 10 m high riser of a circulating fluidized bed (CFB) system. The riser was operated at 4.0 to 10.0 m/s air velocity and 50 to 550 kg/m2s solids flux of spent fluid catalytic cracking (FCC) catalyst particles with 67 μm mean diameter and density of 1500 kg/m3. Data were analyzed using prepared FORTRAN 2008 code to get correlation integral followed by determination of correlation dimensions with respect to the hyperspherical radius and their profiles, plots of which were studied. It was found that correlation dimension profiles at the centre have single peak with higher values than the wall region profiles. Towards the wall, these profiles have double or multiple peaks showing bifractal or multifractal flow behaviors. As the velocity increases the wall region profiles become random and irregular. Further it was found that, as the height increases the correlation dimension profiles shift towards higher hyperspherical radius at the centre and towards lower hyperspherical radius in the wall region at r/R = 0.81. The established method of mapping correlation dimension profiles in this study forms a suitable tool for analysis of high-flux riser dynamics compared to other analyses approaches. However, further analysis is recommended to other gas-solid CFB riser of different dimensions operated at high-flux conditions using the established method.

关键词： Correlation Integral mapping Correlation Dimension High-Flux Gas-Solid Riser Embedded Solid Concentration Time Series

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mapping the Wall-Region Dynamics of High-Flux Gas-Solid Riser Using Scaling Regions from the Solid Concentration Time Series

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Engineering（科研） 2019年第1期11卷 74-92页

An experimental study of the gas-solid flow dynamics in the high-flux CFB riser was accomplished by analysing the scaling regions from solid concentration signals collected from a 76 mm internal diameters and 10 m high riser of a circulating fluidized bed (CFB) system. The riser was operated at 4.0 to 10.0 m/s gas velocity and 50 to 550 kg/m2s solids flux. Spent fluid catalytic cracking (FCC) catalyst particles of 67 μm mean diameter and 1500 kg/m3 density together with 70% to 80% humid air was used. Solid concentration data were analysed using codes prepared in FORTRAN 2008 to get correlation integrals at different embedding dimensions and operating conditions and plot their profiles. Scaling regions were identified by visual inspection method and their location on planes determined. Scaling regions were analysed based on operating conditions and riser spatial locations. It was found that scaling regions occupy different locations on the plane depending on the number of embedding dimensions and operating conditions. As the number of embedding dimensions increases the spacing between scaling regions decreases until it saturates towards higher embedding dimensions. Slopes of scaling regions increases with embedding dimensions until saturation where they become constant. Slopes of scaling regions towards the wall decrease while the number of scaling regions for a particular profile increases. The span of the scaling region is wider at the initial values of hyperspherical radius than its final values. The scaling regions in some flow development sections show multifractal behaviour for each embedding dimension which manifests into visible basin which is defined in this study as multifractal basin. Further, the end points of the scaling region for each correlation integral profile differ from each other as the embedding dimension changes. This study suggests that identification of scaling region by visual inspection method is useful in understanding the gas-solid flow d

关键词： Scaling Region Correlation Integral Correlation Dimension Embedding Dimensions multifractal Basin High-Flux Riser

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Outcomes following liver transplantation in intensive care unit patients

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World Journal of Hepatology 2013年第1期5卷 26-32页

作者： Lena Sibulesky michael G Heckman C Burcin Taner Juan m Canabal Nancy N Diehl Dana K Perry Darren L Willingham Surakit Pungpapong Barry G Rosser David J Kramer justin H Nguyen Department of Transplantation Mayo ClinicJacksonvilleFL 32225United States Biostatistics Unit Mayo ClinicJacksonvilleFL 32225United States Departments of Transplantation and Critical Care medicine Mayo ClinicJacksonvilleFL 32225United States Department of Critical Care medicine and Internal medicine Aurora Health CareMilwaukeeWI 53204United States

AIm:To determine feasibility of liver transplantation in patients from the intensive care unit (ICU) by estimating graft and patient ***:This single center retrospective study included 39 patients who had their first liver transplant directly from the intensive care unit and 927 non-ICU patients who were transplanted from hospital ward or home between January 2005 and December ***:In comparison to non-ICU patients,ICU patients had a higher model for end-stage liver disease (mELD) at transplant (median:37 vs 20,P mmediately prior to liver transplantation (LT) with 6 patients (15%) requiring both vasopressin and *** ICU patients (41%) were ventilator dependent immediately prior to LT with 9 patients undergoing percutaneous tracheostomy prior to ***-five ICU patients (64%) required dialysis *** 1,3 and 5 years after LT,graft survival was 76%,68% and 62% in ICU patients vs 90%,81% and 75% in non-ICU *** survival at 1,3 and 5 years after LT was 78%,70% and 65% in ICU patients vs 94%,85% and 79% in non-ICU *** formally comparing graft survival and patient survival between ICU and nonICU patients using Cox proportional hazards regression models,both graft survival [relative risk (RR):1.94,95%CI:1.09-3.48,P=0.026] and patient survival (RR:2.32,95%CI:1.26-4.27,P=0.007) were lower in ICU patients vs non-ICU patients in single variable *** findings were consistent in multivariable *** not statistically significant,graft survival was worse in both patients with cryptogenic cirrhosis (RR:3.29,P=0.056) and patients who received donor after cardiac death (DCD) grafts (RR:3.38,P=0.060).These findings reached statistical significance when considering patient survival,which was worse for patients with cryptogenic cirrhosis (RR:3.97,P=0.031) and patients who were transplanted with DCD livers (

关键词： Donor pool Donor outcomes Onor after cardiac death grafts Liver graft survival Patient survival

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低渗油藏注气提高采收率技术筛选——以辽河油田齐131块为例

低渗油藏注气提高采收率技术筛选——以辽河油田齐131块为例

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作者： Ezekiel,justin Chima 中国石油大学(华东)

学位级别：硕士

辽河油田Q131区块属于低渗水敏轻质油藏,原始地层压力33.4 mPa,油藏温度98-112℃,地质储量(OOIP)253万m3,地层原油粘度0.5 mPa.s。其特征是油层较厚、地层倾角较大,但地层能量不足,初期压力衰竭开采产量较低。由于渗透率低及水敏严重,... 详细信息

辽河油田Q131区块属于低渗水敏轻质油藏,原始地层压力33.4 mPa,油藏温度98-112℃,地质储量(OOIP)253万m3,地层原油粘度0.5 mPa.s。其特征是油层较厚、地层倾角较大,但地层能量不足,初期压力衰竭开采产量较低。由于渗透率低及水敏严重,后期水驱也未收到成效,目前注水困难,注不进采不出”的矛盾突出。因此,该区块正在考虑实施注气提高采收率技术。注气已经成为一种有效的提高采收率方法,其原理主要在于增加或保持地层压力,提高驱油和波及效率,从而提高原油采收率。根据气源情况,有三种注气技术可以应用于Q131区块:注空气、注CO以及注N。本研究针对Q131工况,考虑了注气高效重力稳定驱替方式在Q131应用的优势,在不同注气技术在目标区块提高采收率机理分析的基础上,对三种技术的技术和经济可行性进行了分析。论文对目标区块的生产历史和及实时数据进行了总结分析,并评估了在本区块进行注气提高采收率的可行性。结合理论分析、注气提高采收率机理、现场经验、室内试验研究、PVT分析和油田生产数据历史拟合,运用CmG-STARS数值模拟软件,建立三种注气技术应用的油藏数值模拟模型。然后根据注入不同气体对保持地层压力、提高采收率、经济性、安全性等的影响进行筛选。对于注空气工艺,在实验基础上建立低温氧化动力学模型并应用于油藏模拟中。注空气低渗岩心驱替实验表明注空气可以得到比水驱更高的采收率,并且其采收率随着地层倾角的增加而增加。温度在130-170°C的轻质油低温氧化实验表明,油层内的产生的自发低温氧化反应能完全消耗O并且CO转换率高达58%。油藏数值模拟结果表明,受注入井位置和数量限制,气体注入速率及注气量是影响原油产量的重要因素。累积产油量随着气体注入速度和注入量增加而增加,并有注入量的最优值。注空气过程中,在模拟的注入量下生产井未没有出现O突破的现象。以单井30000m3/day的速度向地层中注入空气、CO和N(4口注入井)30年,原油采收率分别可达到35%,36.5%,35.5%,其中注入CO的开采效果最好。气体早期突破及油井产出气油比太高是注气工艺的重要问题,关闭的高气油比井是降低气体产出的有效手段。敏感性分析表明,在维持相同注入量下,但采用关闭高气油比油井的方法降低气体产出量,其20年的注入空气、CO和N的原油采收率可分别达到33.5%,36%,and 34%,使得注气项目具有更高的经济性。初期的经济性和安全性分析也证明三种注气技术都具有可行性和经济性。其中,由于操作成本低,注空气成为三种方法中最具前景的方法。此外,详细讨论了不同注气技术安全性和防腐问题,也对低渗油藏更有效开发提出了建议。

关键词：注空气注CO2 注N2 低渗油藏提高采收率空气驱低温氧化实验数值模拟经济安全性评价

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Understanding the agronomic impacts of defoliation strategies in“Bulldog 805”Alfalfa+“Tifton 85”bermudagrass mixed stands

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Grassland Research 2023年第4期2卷 251-259页

作者： Lisa L.Baxter justin C.Burt mary Kimberly mullenix Sydney L.Payne Kaylyn R.Reagin Katie m.mason Chris G.Prevatt Jennifer J.Tucker Department of Crop and Soil Science University of GeorgiaTiftonGeorgiaUSA Department of Animal Science Auburn UniversityAuburnAlabamaUSA Department of Animal Science University of TennesseeKnoxvilleTennesseeUSA Beef Cattle and Forage Commodity Director Alabama Farmers Federation MontgomeryMontgomeryAlabamaUSA Department of Animal and Dairy Science University of GeorgiaTiftonGeorgiaUSA

Background:The incorporation of legumes,specifically alfalfa(medicago sativa L.),into bermudagrass(Cynodon spp.)-based pasture systems in the southeastern United States has increased in recent years as an alternative to synthetic nitrogen(N)***:A small plot evaluation was conducted in Shorter,Alabama,and Tifton,Georgia,USA,to evaluate the impact of harvest height(HH)and harvest frequency(HF)on agronomic characteristics of alfalfa+bermudagrass mixtures in southeastern United ***:Results from both locations revealed that the longer the HF and the shorter the HH,the greater the alfalfa retention was in the stand(pmpact any of the reported nutritive value parameters,while longer HF resulted in lower total digestible nutrients,lower crude protein,higher acid detergent fiber,and lower 48 h in vitro dry matter digestibility(pmpacted forage accumulation at both locations(pmed recent findings from comparable evaluations in the southeastern United States,in that increasing HH and decreasing HF improved alfalfa retention while having a negligible effect on nutritive value or forage accumulation.

关键词： alfalfa+bermudagrass mixtures defoliation management forage management

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