scholarly journals Integrated Periodic Timetabling and Vehicle Circulation Scheduling

2021 ◽  
Author(s):  
Rolf N. Van Lieshout
Keyword(s):  
Public Transport ◽  
Computational Study ◽  
Valid Inequalities ◽  
High Quality ◽  
Trade Off ◽  
The Public ◽  
Average Travel Time ◽  
Periodic Timetabling ◽  
The Cost ◽  
The Impact

Periodic timetabling is one of the most well-researched problems in the public transport optimization literature. However, the impact that timetabling has on the number of required vehicles, which directly translates to operator costs, is rarely considered. Therefore, in this paper, we consider the problem of jointly optimizing the timetable and the vehicle circulation schedule, which specifies the cyclic sequences of trips that vehicles perform. In order to obtain high-quality solutions to realistic instances, we improve an earlier proposed formulation by contraction techniques, three new valid inequalities, and symmetry-breaking constraints. Ultimately, this allows us to explore the trade-off between the number of vehicles and the attractiveness of the timetable from the passengers’ perspective. An extensive computational study demonstrates the effectiveness of the improved formulation. Moreover, using this approach, we are able to find timetables requiring substantially fewer vehicles at the cost of minimal increases of the average travel time of passengers.

scholarly journals Exploring the Impact of Early Decisions in Variable Ordering for Constraint Satisfaction Problems

2018 ◽  
Vol 2018 ◽  
pp. 1-14
Author(s):  
José Carlos Ortiz-Bayliss ◽  
Ivan Amaya ◽  
Santiago Enrique Conant-Pablos ◽  
Hugo Terashima-Marín
Keyword(s):  
Constraint Satisfaction ◽  
Constraint Satisfaction Problems ◽  
Search Cost ◽  
High Quality ◽  
Simple Method ◽  
Variable Ordering ◽  
It Performance ◽  
The Cost ◽  
The Impact ◽  
Variable Ordering Heuristics

When solving constraint satisfaction problems (CSPs), it is a common practice to rely on heuristics to decide which variable should be instantiated at each stage of the search. But, this ordering influences the search cost. Even so, and to the best of our knowledge, no earlier work has dealt with how first variable orderings affect the overall cost. In this paper, we explore the cost of finding high-quality orderings of variables within constraint satisfaction problems. We also study differences among the orderings produced by some commonly used heuristics and the way bad first decisions affect the search cost. One of the most important findings of this work confirms the paramount importance of first decisions. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. We propose a simple method to improve early decisions of heuristics. By using it, performance of heuristics increases.

scholarly journals Using Artificial Intelligence to classify Jobseekers: The Accuracy-Equity Trade-off

2020 ◽  
pp. 1-19
Author(s):  
SAM DESIERE ◽  
LUDO STRUYVEN
Keyword(s):  
Artificial Intelligence ◽  
Maximum Level ◽  
Employment Services ◽  
Trade Off ◽  
The Public ◽  
Foreign Origin ◽  
Trade Offs ◽  
Graphical Tool ◽  
The Cost

Abstract Artificial intelligence (AI) is increasingly popular in the public sector to improve the cost-efficiency of service delivery. One example is AI-based profiling models in public employment services (PES), which predict a jobseeker’s probability of finding work and are used to segment jobseekers in groups. Profiling models hold the potential to improve identification of jobseekers at-risk of becoming long-term unemployed, but also induce discrimination. Using a recently developed AI-based profiling model of the Flemish PES, we assess to what extent AI-based profiling ‘discriminates’ against jobseekers of foreign origin compared to traditional rule-based profiling approaches. At a maximum level of accuracy, jobseekers of foreign origin who ultimately find a job are 2.6 times more likely to be misclassified as ‘high-risk’ jobseekers. We argue that it is critical that policymakers and caseworkers understand the inherent trade-offs of profiling models, and consider the limitations when integrating these models in daily operations. We develop a graphical tool to visualize the accuracy-equity trade-off in order to facilitate policy discussions.

scholarly journals BUCHAREST PUBLIC TRANSPORT: CHALLENGES DURING THE COVID-19 PANDEMIC

2021 ◽  
Vol 11 (S.I.2) ◽  
Author(s):  
Andreea Daniela TUDOR
Keyword(s):  
Public Transport ◽  
Public Transportation ◽  
Transport Sector ◽  
Research Database ◽  
Safety Measures ◽  
The Public ◽  
The People ◽  
To Come ◽  
Main Barrier ◽  
The Impact

The COVID-19 pandemic had and it’s still having a big impact on mobility since the end of 2018, when it started. Public transportation was already facing issues in all the big metropolitan cities where many people are in the same space at the same time. If we add the COVID-19 consequences and rules, public transit is the main barrier for community members to go back to their daily routines being safe and comfortable. This paper presents the changes in the public transport sector since COVID-19 started and aims to explore the consequences and possible alternatives to mitigate the impact of the pandemic crisis. As research method I decided to analyze and summarize numerous primary sources along with the public transport operators’ official websites. Both quantitative and qualitative data were used by doing a comprehensive research in ProQuest Central, Coronavirus Research Database, Elsevier ScienceDirect and Web of Science. The results suggest that reduction of mobility has been the first measure to slow the growth of the worldwide COVID-19 cases. However, the transport limitations don’t have the same impact for all modes of transport, public transport having one of the most considerable decline so far. In Bucharest, the public transport operators have imposed safety measures such as mask wearing, periodic cleaning, transparency and access to the information. Those aspects are important, but sometimes not sufficient to fight against the pandemic. What this research does is to come and complete the set of safety measures focusing on mitigating the spread of the SARS-CoV-2 virus and increase the safety of the people while using public transport vehicles.

scholarly journals THE IMPACT OF FINANCIAL INCENTIVES ON THE QUALITY OF EARLY DIAGNOSIS IN THE PRACTICE OF A DENTIST WHO PROVIDES QUALITY TREATMENT

2021 ◽  
Vol 10 (34) ◽  
Author(s):  
S.S GRECHIKHIN ◽  
Keyword(s):  
Early Diagnosis ◽  
Financial Incentives ◽  
Diagnostic Methods ◽  
Quality Level ◽  
X Rays ◽  
High Quality ◽  
Diagnostic Measures ◽  
The Cost ◽  
The Impact

Diagnostics in the practice of a dentist is the key to quality treatment. However, depending on the quality of services provided, the cost of diagnostic methods is set. For a dentist working in a private office, the key to successful diagnostic measures at a high quality level is a priority. However, these methods are expensive for the patient. The purpose of this study is to study the impact of financial incentives on the quality of early diagnosis in the practice of a dentist who provides quality treatment. In the study, we studied clinical cases with full and partial study in terms of diagnostic and neglect x-ray diagnosis from the doctor and from the patient due to a misunderstanding of the importance and necessity of this manipulation. In statistical data analysis, the resulting regression models use a binary variable as a dependent variable on the level of financial costs. Thus, in the course of our research, we found that the number of x-rays significantly increases when dentists receive a fee for services, rather than a salary, and when patients are exempt from paying for additional diagnostic methods. Our results show that financial incentives significantly influence additional high-quality and complete examination of patients.

scholarly journals Conditions for the functioning of regulated competition on the public urban transport market in Poland

2018 ◽  
Vol 80 ◽  
pp. 119-127
Author(s):  
Grzegorz Krawczyk
Keyword(s):  
Large Volume ◽  
Public Transport ◽  
Natural Monopoly ◽  
Urban Transport ◽  
Quality Of Services ◽  
The Public ◽  
Transport Organization ◽  
The Cost ◽  
Regulated Competition

The public urban transport market takes the form of a natural monopoly. In some cases, especially in the situation of supply of a relatively large volume of operation work, the implementation of competitive solutions may result in: improving the quality of services or reducing the cost of vehicle-kilometers. The purpose of the article is to present the determinants of functioning of regulated competition on the public urban transport market in Poland. The conducted analysis focuses on the issue of market openness and access to participation in competitive procedures of private operators. The research covered urban transport markets in cities over 200.000 inhabitants and their characteristics in the scope of: the model of public transport organization (with particular emphasis on the level of opening of markets), the level of competition on the operator market and the method of selecting operators. On the basis of the conducted research, the scope of applying pro-competitive solutions in the scope of contracting services by the largest organizers of public urban transport in Poland was characterized.

scholarly journals Synchronizing vigilance or taking turns as sentinels? The importance of testing coordination

2020 ◽  
Author(s):  
Annemarie van der Marel ◽  
Jane M. Waterman ◽  
Marta López-Darias
Keyword(s):  
Habitat Structure ◽  
High Quality ◽  
Alarm Signal ◽  
Trade Off ◽  
Optimal Activity ◽  
Behavioral Observations ◽  
Individual Survival ◽  
Low Costs ◽  
The Cost ◽  
Diurnal Species

AbstractDiurnal species can reduce the cost of the trade-off between feeding and predation risk by 1) performing low-quality (vigilance while performing another behavior) instead of high-quality vigilance (only performing vigilance) or 2) by vigilance coordination either by taking turns acting as sentinels or by synchronizing vigilance bouts. A sentinel system assumes that sentinels are located at raised positions, alarm signal, and alternate vigilance bouts. However, many species with a described sentinel system have not been tested yet for coordination. We set out to study coordinated behavior and the reasons for this behavior in the invasive Barbary ground squirrel, Atlantoxerus getulus, using behavioral observations and genetic analyses. This species performs a type of vigilance (‘perch behavior’) seemingly similar to sentinel behavior as individuals performed high-quality vigilance at raised locations for over 30 s, but alternating coordination is unknown. Perch behavior was coordinated but synchronized instead of taking turns (sentinel). Both sexes performed perch behavior and individuals performed perch behavior in the absence and presence of kin and offspring. We found that survival or time spent foraging did not decrease for perched individuals, nor that individual survival increased. Perch behavior in the invasive population of A. getulus may be synchronized 1) to perform an optimal activity when satiated (low costs), and, 2) may be an adaptation to habitat structure (large benefits). Our study demonstrates that the cost of the vigilance/foraging trade-off may not be high for invasive species and argued the importance of testing for coordination in species with described sentinel systems.

scholarly journals Assessment of the Impact of Public Transport Accessibility on the Value of Urban Residential Real Estate

2021 ◽  
Vol 20 (1) ◽  
pp. 62-83
Author(s):  
E. V. Leontev ◽  
◽  
I. A. Mayburov ◽  
Keyword(s):  
Real Estate ◽  
Public Transport ◽  
Real Estate Market ◽  
Transport Infrastructure ◽  
Lower Sensitivity ◽  
Residential Real Estate ◽  
Metro Station ◽  
Average Value ◽  
The Cost ◽  
The Impact

Currently, analysis of the impact of public transport on real estate and its value is widely demanded in the world. The analysis is used to plan investments in public transport and the efficiency of public transport networks. In Russia, such studies have been carried out mainly in the framework of the evaluation of specific properties, which does not make it possible to macroanalyze the urban public transport environment and compare them with each other. The aim of the work is to study the influence of the proximity of public transport infrastructure on the cost of urban residential real estate, to determine the average value of such an impact for Yekaterinburg. In this study, we intend to confirm the hypothesis about different influence of the proximity of a public transport stop on the cost of housing, taking into account the different set of attributes that characterize it. The calculations were carried out using the analysis of the supply of the real estate market, carried out with the method of multiple regression, simultaneously with the geo-positioning of real estate units on the map to calculate the distance of each object to the nearest public transport stop of a certain type. Based on the results of the calculations, a global tendency towards a higher cost of the properties that are close to tram stops or metro stations in Yekaterinburg is confirmed, and the share of the value of a property generated by the proximity of a public transport stop was calculated. The authors confirmed the hypothesis about varying sensitivity of residential real estate to the proximity of public transport stops. Newer homes have lower sensitivity to proximity to public transport stops than older ones. The obtained empirical evidence of the influence of public transport infrastructure on the value of residential real estate demonstrates the most significant contribution to the value of a real estate object, the proximity to the metro station in Yekaterinburg (3.0 – 12.0%). The tram infrastructure showed a slightly lower impact on the total cost of the facility (3.2 – 8.8%). The revealed interdependencies make it possible to apply the obtained data to forecasting the growth of the taxable base for property tax during the construction of new transport lines.

scholarly journals Disaster politics: Cyclone politicking and electioneering in the Kingdom of Tonga

Te Kaharoa ◽  
2014 ◽  
Vol 7 (1) ◽  
Author(s):  
Teena Brown Pulu
Keyword(s):  
Prime Minister ◽  
Local Economy ◽  
Public Servants ◽  
Political Spectacle ◽  
The Public ◽  
Finance Minister ◽  
The Right ◽  
The Masses ◽  
The Cost ◽  
The Impact

Entering the new year of 2014 the Kingdom of Tonga had enough to worry about; a local economy choking to near death and a finance minister sacked and replaced in a political spectacle leaving the public baffled over what went wrong between him and the Prime Minister (Fayle, 2014; Lopeti, 2014c; Fonua, 2014b).  People uttered they looked forward to the end of year election tentatively set for Thursday November 27th.  The 2010 register of around forty thousand voters had increased at the 2014 intake by four thousand, mostly voters who had turned the age of suffrage at twenty one years old.  The chorus call from the masses was simple, vote them out.  Then Cyclone Ian struck on Saturday 11 January 2014 aggravating Tonga’s money shortage. Journalist Pesi Fonua wrote “the impact on the Tongan economy of the cyclone and the salary rise for civil servants at this point of time is a matter of great concern” (Fonua, 2014a).  He was right.  The state and taxpayers could not afford economic recovery from Tonga’s cruellest cyclone, a symptom of climate change, let alone paying for a 5% rise in the cost of living allowance for public servants.  As the national debt distress sore became inflamed the Public Service Association decided it was the right time to fight cabinet for a 22% living allowance rise because 5% was not enough (Lopeti, 2014a).  This essay asks a pointed question.  Leading up to the general election of November 2014, how was cyclone politicking being manoeuvred to sway the way people would vote?

scholarly journals Public Transport to the Airport and Its Influence on Handling Process

2019 ◽  
Vol 7 (1) ◽  
pp. 6-11
Author(s):  
Slobodan Stojić ◽  
Vladimir Pazdro ◽  
Roman Vokáč
Keyword(s):  
Public Transport ◽  
Waiting Times ◽  
Control Process ◽  
Business Environment ◽  
Airport Security ◽  
The Czech Republic ◽  
The Public ◽  
Mass Public ◽  
The Impact ◽  
The Given

The paper focuses on several possibilities of the mass public transport to the airport, including analyses of the expected impact on the various airport processes. Within the article, three main transportation system types will be described and compared. Firstly, the problem regarding current bus transfer system to the Václav Havel airport Prague will be analyzed. According to the analysis results the focus now turns to the description of the potential influence of the introduction of the new transfer systems, including the impact on the airport security and passport control process, and other procedures, which include some kind of a queuing process. This airport was chosen as the biggest airport in the Czech Republic, which in today and future business environment could expect problems related to the public transport of the passengers to and from the airport. Besides the description of the current structure, the paper tries to elaborate issues such as calculation of the queue waiting times and to propose a new system, more suitable for the given conditions. Results of the research include various calculations, such dependence of a modal split and intervals of the waiting times within a check-in process.

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