Development and Validation of Improved Impedance Functions for Roads with Mixed Traffic Using Taxi GPS Trajectory Data and Simulation

This paper proposes an improved impedance function for roads with mixed traffic. It is known that only limited studies consider the impact of nonmotorized traffic on travel impedance of a road segment, and a comparison of the impedance considering nonmotorized traffic with the classic BPR function, which does not consider the former, is scarce. Most of the previous studies targeted road conditions in developed countries, where the presence of nonmotorized traffic is negligible, and therefore limited efforts have been invested to develop improved impedance function considering mixed traffic. To overcome this limitation, this paper develops an improved impedance function and carries out a case study for a road in the city of Wuhan, China. The improved impedance function explicitly considers the interaction between motorized and nonmotorized traffic. Taxi GPS data from the case study road is used to extract and analyze the travel time of the “probe vehicles” running through the sampled segment at any time during a sampling day. The capacity of the road segment is measured, and the traffic flow of motorized vehicles and nonmotorized vehicles on the segment is counted. Based on the above data, the classic BPR function and the improved one proposed in this paper are calibrated. After comparing and analyzing the observed road impedance based on both analytical and simulation results, the classic BPR function and the proposed impedance function, the proposed impedance function is found to be more accurate to simulate the observed road impedance, with the error reducing from 14.83 s with the classic BPR impedance function to 6.50 s with the improved function. The proposed impedance function possesses a simple structure and high flexibility, and the parameters calibrated in this paper can be applied to similar roads to provide more realistic impedance than the previous ones based on the classic BPR function. The calibrated improved impedance function’s transferability to other similar roads is validated by applying it to another road and the results show that the percentage error between the predicted travel times and the observed ones is only 3.8%.

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Gender and feminist considerations in Artificial Intelligence from a developing-world perspective, with India as a case study

10.31124/advance.17054936 ◽

2021 ◽

Author(s):

SANGHAMITRA CHOUDHURY ◽

Shailendra Kumar

Keyword(s):

Artificial Intelligence ◽

Developing Countries ◽

Developing World ◽

Developed Countries ◽

High Level ◽

The Impact ◽

The Relationship ◽

Precarious Situation ◽

And Robotics

<p>The relationship between women, technology manifestation, and likely prospects in the developing world is discussed in this manuscript. Using India as a case study, the paper goes on to discuss how ontology and epistemology views utilised in AI (Artificial Intelligence) and robotics will affect women's prospects in developing countries. Women in developing countries, notably in South Asia, are perceived as doing domestic work and are underrepresented in high-level professions. They are disproportionately underemployed and face prejudice in the workplace. The purpose of this study is to determine if the introduction of AI would exacerbate the already precarious situation of women in the developing world or if it would serve as a liberating force. While studies on the impact of AI on women have been undertaken in developed countries, there has been less research in developing countries. This manuscript attempts to fill that need.</p>

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Saturation Flow Model for Signalized Intersection under Mixed Traffic Condition

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198118777407 ◽

2018 ◽

Vol 2672 (15) ◽

pp. 55-65 ◽

Cited By ~ 7

Author(s):

Sabyasachi Biswas ◽

Souvik Chakraborty ◽

Indrajit Ghosh ◽

Satish Chandra

Keyword(s):

Conventional Method ◽

Detailed Comparison ◽

Heterogeneous Traffic ◽

Signalized Intersection ◽

Percentage Error ◽

Mixed Traffic ◽

Kriging Method ◽

Traffic Condition ◽

Saturation Flow ◽

The Impact

Saturation flow is one of the most important functional parameters at signalized intersections. It is to be noted that saturation flow is a functional measure of the intersection operation, which indicates the probable capacity if working in an ideal situation. However, determination of the saturation flow is a challenging task in developing countries like India where vehicles with diverse static and dynamic characteristics use the same carriageway. At the same time, it is influenced by several other factors. In this context, the present research is carried out to examine the effects of traffic composition, approach width and right-turning movements on saturation flow under heterogeneous traffic conditions. This paper proposes a model for computing saturation flow at the signalized intersection under mixed traffic condition based on Kriging approach. A detailed comparison of the mean saturation flow values obtained by the conventional method, regression method, and Kriging method has also been presented. Low mean absolute percentage error values (<5%) have been obtained for saturation flow by Kriging method with respect to the conventional method. Finally, the proposed models are used to evaluate the impact of right-turning vehicles on saturation flow under shared lane condition.

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The Impact of the 2008 World Financial Crisis on Homelessness in Developed Countries : The Case Study of New York City = أثر الأزمة المالية العالمية عام 2008 على ظاهرة التشرد في الدول المتحضرة : دراسة حال مدينة نيويورك

Dirasat Human and Social Sciences ◽

10.12816/0040582 ◽

2017 ◽

Vol 44 (3) ◽

pp. 269-280

Author(s):

Hussaen A. H. Kahachi

Keyword(s):

New York ◽

New York City ◽

Financial Crisis ◽

York City ◽

Developed Countries ◽

The Impact

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The impact of the multinational corporations on leading issues and policy making in less developed countries : (a case study on Kenya)

10.15760/etd.5135 ◽

1985 ◽

Author(s):

Wamukota Wambalaba

Keyword(s):

Multinational Corporations ◽

Policy Making ◽

Developed Countries ◽

Less Developed Countries ◽

The Impact

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Productivity Effect Evaluation on Market-Type Environmental Regulation: A Case Study of SO2 Emission Trading Pilot in China

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17218027 ◽

2020 ◽

Vol 17 (21) ◽

pp. 8027

Author(s):

Yanhong Feng ◽

Shuanglian Chen ◽

Pierre Failler

Keyword(s):

Environmental Regulation ◽

Large Scale ◽

Emission Trading ◽

Moderating Effects ◽

So2 Emissions ◽

Productivity Level ◽

Productivity Effect ◽

High Flexibility ◽

The Impact

Taking China’s SO2 emissions trading pilot (ETP) in 2007, a large-scale market-based environmental regulation as its target, this paper reexamines the strong Porter hypothesis by adopting the method of propensity score matching-differences-in-differences. Research shows the following results: first, SO2 ETP which provides high flexibility for enterprises in the process of emission reduction, improves total factor productivity (TFP) significantly on the whole. Second, the productivity effect of market-based environmental regulation varies from the productivity level of enterprise. For example, the SO2 ETP has a significant effect on TFP only at 40–80 percent quantile of TFP, and the effect increases at first and then decreases. Third, the financing constraints and bargaining power of enterprises have significant negative moderating effects on the impact of SO2 ETP on TFP, and the moderating effects between state-owned and non-state-owned enterprises exist heterogeneity. In conclusion, it provides reference for the formulation of market-type environmental regulations and the realization of high-quality development for developing countries.

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Operational safety of automated and human driving in mixed traffic environments: A perspective of car-following behavior

Proceedings of the Institution of Mechanical Engineers Part O Journal of Risk and Reliability ◽

10.1177/1748006x211050696 ◽

2021 ◽

pp. 1748006X2110506

Author(s):

Tao Li ◽

Xu Han ◽

Jiaqi Ma ◽

Marilia Ramos ◽

Changju Lee

Keyword(s):

Traffic Safety ◽

Risk Mitigation ◽

Safety Evaluation ◽

Mixed Traffic ◽

Trajectory Data ◽

Road Transportation ◽

Baseline Model ◽

Car Following ◽

On The Road ◽

The Impact

The advent of automated vehicles (AVs) will provide opportunities for safer, smoother, and smarter road transportation. During the transition from the current human-driven vehicle (HV) to a fully AV traffic environment, there will be a mixed traffic flow including both HVs and AVs. The impact of introducing AVs into existing traffic, however, has not yet been fully understood. In this paper, we advance this understanding by conducting mixed traffic safety evaluation from the perspective of car-following behavior using real-world AV operational data of mixed traffic. To understand how the AVs impact other vehicles on the road, we analyzed the operational behaviors of HV-following-HV, AV-following-HV, and HV-following-AV. A selected car-following model is calibrated, and results show that there are significant differences between the HV-following-HV and the other two groups, indicating safe AV behavior and changes in HV behavior (i.e. less aggressive, safer) after the introduction of AVs into the traffic. Additionally, to understand AV behavioral safety, we investigate behavior predictions (one of the most critical inputs for AVs to make car-following decisions) of AVs and their surrounding vehicles using a mature baseline model and a new Conditional Variational Autoencoder (CVAE) framework. The result shows potential risks of inaccurate predictions of the baseline model and the necessity to consider additional factors, such as vehicle interactions and driver behavior, into the prediction for risk mitigation. Arterial vehicle trajectory data from the Lyft Level 5 Dataset is applied to test the proposed methodological framework to understand the car-following safety risks of HVs and AVs in the mixed traffic stream.

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Academic consulting – income stream, impact and brand building

International Journal of Innovation Science ◽

10.1108/ijis-08-2017-0075 ◽

2018 ◽

Vol 10 (2) ◽

pp. 143-159 ◽

Cited By ~ 1

Author(s):

Heidi Kinnunen ◽

Emmi Holm ◽

Anna-Maria Nordman ◽

Solveig Roschier

Keyword(s):

Knowledge Exchange ◽

Developed Countries ◽

Content Type ◽

Brand Building ◽

International Benchmarking ◽

Income Stream ◽

Corporate Funding ◽

The Impact ◽

Time Limitations

Purpose Universities are expected to accelerate and optimize their role as economic growth engines. Technology transfer is a traditional way of expanding knowledge exchange, and it is typically used in hard sciences. This paper aims to discuss academic consultancy as a novel way to bring especially social sciences, humanities and arts (SSHA sciences) knowledge into the society. In addition, it seeks practical ways to combine both university’s and individual researcher’s needs in consultancy. Design/methodology/approach A case study comprising interviews at two Finnish universities was conducted. Literature on academic consulting was used as background knowledge. International benchmarking was done through interviews and desk top studies. Some background statistics was extracted from the financial database for received research funding from businesses and ministries. Findings Corporate funding is most prominent in hard sciences, and SSHA sciences seem to get their funding mainly from public sources. SSHA researchers provide services for firms, but these relationships are generally private. According to interviews, there is will to consult firms through university, but researcher’s time limitations, remuneration and academic merit related to consultancy are important factors when consultancy guidelines are drawn. The administration view is expanded from only research staff to include the entire university knowledge production ecosystem and its members. Originality/value Acknowledging the value of SSHA sciences is topical because the respect towards humanities and social studies seems to be in decline in some developed countries. However, according to this study, academic consulting could have great potential in bringing the human perspective into the digitalized society. The quantification of knowledge exchange would benefit from formal, institutionalized consultancy sales. More studies are needed to assess the impact of academic consultancy on society.

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Organizational Culture and Employees’ Performance: A Case Study of Independent General Directorate of Kochies (Nomads) in Afghanistan

Addaiyan Journal of Arts, Humanities and Social Sciences - Volume-1: Issue-10 (December, 2019) ◽

10.36099/ajahss.2.1.5 ◽

2020 ◽

Vol 2 (1) ◽

pp. 36-46

Author(s):

Mirwais Ahmadzai

Keyword(s):

Organizational Culture ◽

Job Performance ◽

Employee Performance ◽

Pearson Correlation ◽

Developed Countries ◽

Managing Change ◽

The Developed Countries ◽

The Impact ◽

Cultural Strength

The aim of the study is to examine the positive relationshipbetween organizational culture and employees’ performance. The studyfurther assessed the impact of five facets of organizational culture onemployees’ job performance. The study used an adapted questionnaire forthe purpose of data collection. All the staff of the Independent GeneralDirectorate of Kochies (IGDK) at the central office was taken as thesample. The result of the Pearson correlation revealed a positiverelationship between organizational culture and employees’ jobperformance. The result of regression analysis revealed that the four facetsof organizational culture namely managing change, achieving goals,coordinating teamwork and cultural strength positively and significantlycontributed towards employees’ performance whereas the fifth facetclients’ orientation does not contribute towards employee performance. Asa majority of the available literature on the topic in hand was carried outin the developed countries, therefore, this research tried to assess it in thecontext of developing countries like Afghanistan.

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