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Diamond Interchange performance measures Using Connected Vehicle Data

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Journal of Transportation Technologies 2022年第3期12卷 475-497页

作者： Enrique Saldivar-Carranza Steven Rogers Howell Li Darcy Michael Bullock Purdue University West Lafayette USA

Diamond interchanges are frequently used where a freeway intersects a two-way surface street. Most of the techniques to evaluate the performance of diamond interchanges rely on the Highway Capacity Manual (HCM), simulation, Automated Traffic Signal performance measures (ATSPMs), and historical crash data. HCM and simulation techniques require on-site data collection to obtain models’ inputs. ATSPMs need high-resolution controller event data acquired from roadway sensing equipment. Safety studies typically need 3 to 5 years of crash data to provide statistically significant results. This study utilizes commercially available connected vehicle (CV) data to assess the performance and operation of a three- and four-phase diamond interchange located in Indianapolis, Indiana, and Dallas, Texas, respectively. Over 92,000 trajectories and 1,400,000 GPS points are analyzed from August 2020 weekdays CV data. Trajectories are linear-referenced to generate Purdue Probe Diagrams (PPDs) from which arrivals on green (AOG), split failures, downstream blockage, and movement-based control delay are estimated. In addition, an extension of the PPD is presented that characterizes the complete journey of a vehicle travelling through both signals of the diamond interchange. This enhanced PPD is a significant contribution as it provides an analytical framework and graphical summary of the operational characteristics of how the external movements traverse the entire system. The four-phase control showed high internal progression (99% AOG) compared to the moderate internal progression of the three-phase operation (64% AOG). This is consistent with the design objectives of three- and four-phase control models, but historically these quantitative AOG measures were not possible to obtain with just detector data. Additionally, a graphical summary that illustrates the spatial distribution of hard-braking and hard-acceleration events is also provided. The presented techniques can be used by any ag

关键词： performance measures Safety Connected Vehicle Trajectories Diamond Interchange

Diverging Diamond Interchange performance measures Using Connected Vehicle Data

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Journal of Transportation Technologies 2021年第4期11卷 628-643页

作者： Enrique D. Saldivar-Carranza Howell Li Darcy M. Bullock Purdue University West Lafayette USA

Since the first Diverging Diamond Interchange (DDI) implementation in 2009, most of the performance studies developed for this type of interchange have been based on simulations and historical crash data, with a small number of studies using Automated Traffic Signal Performance Measures (ATSPM). Simulation models require considerable effort to collect volumes and to model actual controller operations. Safety studies based on historical crashes usually require from 3 to 5 years of data collection. ATSPMs rely on sensing equipment. This study describes the use of connected vehicle trajectory data to analyze the performance of a DDI located in the metropolitan area of Fort Wayne, IN. An extension of the Purdue Probe Diagram (PPD) is proposed to assess the levels of delay, progression, and saturation. Further, an additional PPD variation is presented that provides a convenient visualization to qualitatively understand progression patterns and to evaluate queue length for spillback in the critical interior crossover. Over 7000 trajectories and 130,000 GPS points were analyzed between the 7th and the 11th of June 2021 from 5:00 AM to 10:00 PM to estimate the DDI’s arrivals on green, level of service, split failures, and downstream blockage. Although this technique was demonstrated for weekdays, the ubiquity of connected vehicle data makes it very easy to adapt these techniques to analysis during special events, winter storms, and weekends. Furthermore, the methodologies presented in this paper can be applied by any agency wanting to assess the performance of any DDI in their jurisdiction.

关键词： Diverging Diamond Interchange performance measures Connected Vehicle Big Data

Congruity of Multiple performance measures

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Journal of Modern Accounting and Auditing 2005年第2期1卷 30-41页

作者： Guanghua Yuan Zengbiao Yu Tsinghua University

In multi-action situation, there are losses of efficiency due to noise effect and incongruity effect. To isolate noise effect, we prove that the loss of efficiency is zero if and only if the objective of the principal is a linear representation of the performance measures when the performance measures are noiseless. Using this result, several definitions of incongruity are given. Our definitions extend the single performance definition given in Feltham and Xie （1994） to multiple performance measures situation, and reconcile the conflict between the definition given in Datar et al. （2001） and that in Feltham and Xie （1994）. A numeric example is analyzed to show the way that the variances of measures and correlation coefficient between measures affect the utility of the principal.

关键词： congruity performance measures principal-agent theory

Continuous Flow Intersection performance measures Using Connected Vehicle Data

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Journal of Transportation Technologies 2022年第4期12卷 861-875页

作者： Enrique Saldivar-Carranza Howell Li Mark Taylor Darcy Michael Bullock Purdue University West Lafayette USA Utah Department of Transportation Salt Lake City USA

Continuous flow intersections (CFIs), also known as displaced left turns (DLTs), are a type of alternative intersection designed to improve operations at locations with heavy left-turn movements by reallocating these vehicles to the left side of opposing traffic. Currently, simulation is commonly used to evaluate operational performance of CFIs. However, this approach requires significant on-site data collection and is highly dependent on the analyst’s ability to correctly model the intersection and driver behavior. Recently, connected vehicle (CV) trajectory data has become widely available and presents opportunities for the direct measurement of traffic signal performance measures. This study utilizes CV trajectory data to analyze the performance of a CFI located in West Valley City, UT. Over 4500 trajectories and 105,000 GPS points are analyzed from August 2021 weekday data. Trajectories are linear-referenced to generate Purdue Probe Diagrams (PPDs) and extended PPDs to estimate split failures (SF), arrivals on green (AOG), traditional Highway Capacity Manual (HCM) level of service (LOS), and the distribution of stops. The estimated operational performance showed effective progression during the PM peak period at all the critical internal storage areas with AOG levels at exit traffic signals between 83% and 100%. In contrast, all external approaches with longer queue storage areas had AOG values ranging from 2% to 81% during the same time period. The presented analytical techniques and summary graphics provide practitioners with tools to evaluate the performance of any CFI where CV trajectories are available without the need for on-site data collection.

关键词： performance measures Connected Vehicles Trajectories Continuous Flow Intersection Displaced Left Turn

Analysis of Historic Pavement and Bridge Conditions and Alternative Funding Levels for the Michigan Department of Transportation

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Journal of Traffic and Transportation Engineering 2024年第3期12卷 107-118页

作者： William Robert Spy Pond Partners LLCArlingtonMA 02474USA

In 1997 the Michigan Department of Transportation (MDOT) established an ambitious set of condition targets for its pavements and bridges, and the Department received increased revenue from a 4-cent-per-gallon increase in the state motor fuels tax to help meet its targets. However, over time, actual revenue was less than both what was initially estimated as needed to meet the targets and what was projected from the tax increase. Consequently, actual conditions were projected to fall short of the target levels, so the department issued bonds to address the shortfall through 2012. To support deliberations on future funding, in 2013 MDOT performed an analysis of historic conditions to determine what additional fuel tax revenues would have been required beginning in 1997 to: replace bond revenues used to fund pavement and bridge projects from 1997 to 2012;and enable MDOT to meet its condition targets. The analysis was performed using data on actual pavement and bridge funding and conditions;as well as predicted funding and conditions for different hypothetical increases in fuel taxes. The analysis concluded that, in addition to the actual increase of 4 cents per gallon, a fuel tax increase of another 10 cents per gallon would have been required in 1997 to replace bond revenue used for pavement and bridges and allow MDOT to meet its condition targets. The analysis results were used to help inform the discussion of Michigan’s target asset conditions and funding, and demonstrate application of MDOT’s pavement and bridge management systems for performing historic analyses.

关键词： Transportation asset management transportation finance performance measures pavement management bridge management

Predicting protein subchloroplast locations:the 10th anniversary

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Frontiers of Computer Science 2021年第2期15卷 1-11页

作者： Jian SUN Pu-Feng DU College of Intelligence and Computing Tianjin UniversityTianjin300350China

Chloroplast is a type of subcellular organelle in green plants and *** is the main subcellular organelle for conducting photosynthetic *** proteins,which localize within the chloroplast,are responsible for the photosynthetic process at molecular *** chloroplast can be further divided into several *** in different compartments are related to different steps in the photosynthetic *** the molecular function of a protein is highly correlated to the exact cellular localization,pinpointing the subchloroplast location of a chloroplast protein is an important step towards the understanding of its role in the photosynthetic *** process for determining protein subchloroplast location is always costly and time ***,computational approaches were developed to predict the protein subchloroplast locations from the primary *** the last decades,more than a dozen studies have tried to predict protein subchloroplast locations with machine learning *** sequence features and various machine learning algorithms have been introduced in this research *** this review,we collected the comprehensive information of all existing studies regarding the prediction of protein subchloroplast *** compare these studies in the aspects of benchmarking datasets,sequence features,machine learning algorithms,predictive performances,and the implementation *** summarized the progress and current status in this special research *** also try to figure out the most possible future works in predicting protein subchloroplast *** hope this review not only list all existing works,but also serve the readers as a useful resource for quickly grasping the big picture of this research *** also hope this review work can be a starting point of future methodology studies regarding the prediction of protein subchloroplast locations.

关键词： subchloroplast locations sequence features performance measures online services machine learning

Classification Model for IDS Using Auto Cryptographic Denoising Technique

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Computer Systems Science & Engineering 2023年第4期45卷 671-685页

作者： N.Karthikeyan P.Sivaprakash S.Karthik Department of Computer Science&Engineering PPG Institute of TechnologyCoimbatoreTamilnaduIndia Department of Computer Science&Engineering SNS College of TechnologyCoimbatoreTamilnaduIndia

Intrusion detection systems(IDS)are one of the most promising ways for securing data and networks;In recent decades,IDS has used a variety of categorization *** classifiers,on the other hand,do not work effectively unless they are combined with additional algorithms that can alter the classifier’s parameters or select the optimal sub-set of features for the *** are used in tandem with classifiers to increase the stability and with efficiency of the classifiers in detecting *** algorithms,on the other hand,have a number of limitations,particularly when used to detect new types of *** this paper,the NSL KDD dataset and KDD Cup 99 is used to find the performance of the proposed classifier model and compared;These two IDS dataset is preprocessed,then Auto Cryptographic Denoising(ACD)adopted to remove noise in the feature of the IDS dataset;the classifier algorithms,K-Means and Neural network classifies the dataset with adam *** classifier is evaluated by measuring performance measures like f-measure,recall,precision,detection rate and *** neural network obtained the highest classifying accuracy as 91.12%with drop-out function that shows the efficiency of the classifier model with drop-out function for KDD Cup99 *** their power and limitations in the proposed methodology that could be used in future works in the IDS area.

关键词： Auto cryptographic denoising(ACD) classifier intrusion detection system(IDS) optimizer performance measures

A Fully Adaptive Active Queue Management Method for Congestion Prevention at the Router Buffer

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Computers, Materials & Continua 2023年第11期77卷 1679-1698页

作者： Ali Alshahrani Ahmad Adel Abu-Shareha Qusai Y.Shambour Basil Al-Kasasbeh Faculty of Computer Studies Arab Open UniversityRiyadh11681Saudi Arabia Faculty of Information Technology Al-Ahliyya Amman UniversityAmman19111Jordan

Active queue management(AQM)methods manage the queued packets at the router buffer,prevent buffer congestion,and stabilize the network *** bursty nature of the traffic passing by the network routers and the slake behavior of the existing AQM methods leads to unnecessary packet *** paper proposes a fully adaptive active queue management(AAQM)method to maintain stable network performance,avoid congestion and packet loss,and eliminate unnecessary packet *** proposed AAQM method is based on load and queue length indicators and uses an adaptive mechanism to adjust the dropping probability based on the buffer *** proposed AAQM method adapts to single and multiclass traffic *** simulation results over two types of traffic showed that the proposed method achieved the best results compared to the existing methods,including Random Early Detection(RED),BLUE,Effective RED(ERED),Fuzzy RED(FRED),Fuzzy Gentle RED(FGRED),and Fuzzy BLUE(FBLUE).The proposed and compared methods achieved similar results with low or moderate traffic ***,under high traffic load,the proposed AAQM method achieved the best rate of zero loss,similar to BLUE,compared to 0.01 for RED,0.27 for ERED,0.04 for FRED,0.12 for FGRED,and 0.44 for *** throughput,the proposed AAQM method achieved the highest rate of 0.54,surpassing the BLUE method’s throughput of *** delay,the proposed AAQM method achieved the second-best delay of 28.51,while the BLUE method achieved the best delay of 13.18;however,the BLUE results are insufficient because of the low ***,the proposed AAQM method outperformed the compared methods with its superior throughput and acceptable delay.

关键词： Active queue management dropping rate delay loss performance measures

Modeling discrete-time analytical models based on random early detection: Exponential and linear

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International Journal of Modeling, Simulation, and Scientific Computing 2015年第3期6卷 85-106页

作者： Hussein Abdel-Jaber Fadi Thabtah Mike Woodward Department of Information Technology and Computing Faculty of Computer Studies Arab Open University Kingdom of Saudi Arabia Ebusiness Department Canadian University of DubaiUAE Department of Computing University of Bradford Bradford BD71DPUK

Congestion control is among primary topics in computer network in which random early detection(RED)method is one of its common ***,RED suffers from drawbacks in particular when its“average queue length”is set below the buffer’s“minimum threshold”position which makes the router buffer quickly *** deal with this issue,this paper proposes two discrete-time queue analytical models that aim to utilize an instant queue length parameter as a congestion *** assigns mean queue length(mql)and average queueing delay smaller values than those for RED and eventually reduces buffers overflow.A comparison between RED and the proposed analytical models was conducted to identify the model that offers better *** proposed models outperform the classic RED in regards to mql and average queueing delay measures when congestion *** work also compares one of the proposed models(RED-Linear)with another analytical model named threshold-based linear reduction of arrival rate(TLRAR).The results of the mql,average queueing delay and the probability of packet loss for TLRAR are deteriorated when heavy congestion occurs,whereas,the results of our RED-Linear were not impacted and this shows superiority of our model.

关键词： Analytical modeling congestion control discrete-time queues performance measures simulation