Improved Path Flow Estimator for Origin–Destination Trip Tables

2005 ◽  
Vol 1923 (1) ◽  
pp. 9-17 ◽  
Author(s):  
Piya Chootinan ◽  
Anthony Chen ◽  
Will Recker
Keyword(s):  
Error Bounds ◽  
Lagrange Multipliers ◽  
Transportation Network ◽  
Location Theory ◽  
Set Covering ◽  
Traffic Counts ◽  
Minimum Number ◽  
Covering Model ◽  
Path Flow Estimator

Path flow estimator (PFE) is a one-stage network observer that can estimate path flows and path travel times from traffic counts in a transportation network. Because a unique set of path flows is readily available from the PFE, a trip table can be estimated by simply adding up flows on all the paths connecting individual origin–destination (O-D) pairs. In this paper, the effects of the number and locations of traffic counts on the quality of the O-D trip table estimated by PFE are examined. The set-covering model, studied in the location theory, is applied to determine the minimum number of traffic counts and their corresponding locations required to observe the total demand of the study network. Next, the effects of the error bounds used in PFE to handle the inconsistency problem of traffic counts are examined, and a heuristic using the Lagrange multipliers to facilitate the adjustment of such error bounds is provided. Numerical results show that PFE can correctly estimate the total demand of the study area if a sufficient number of traffic counts collected at appropriate locations is provided. The results further indicate that improper specification of the error bounds could lead to biased estimation of total demand utilizing the network.

scholarly journals Q-Learnheuristics: Towards Data-Driven Balanced Metaheuristics

Mathematics ◽  
2021 ◽  
Vol 9 (16) ◽  
pp. 1839
Author(s):  
Broderick Crawford ◽  
Ricardo Soto ◽  
José Lemus-Romani ◽  
Marcelo Becerra-Rozas ◽  
José M. Lanza-Gutiérrez ◽  
...  
Keyword(s):  
Combinatorial Problems ◽  
Set Covering ◽  
Covering Problem ◽  
Integration Framework ◽  
Q Learning ◽  
Whale Optimization ◽  
Sine Cosine Algorithm ◽  
Exploration Exploitation ◽  
Selection Of

One of the central issues that must be resolved for a metaheuristic optimization process to work well is the dilemma of the balance between exploration and exploitation. The metaheuristics (MH) that achieved this balance can be called balanced MH, where a Q-Learning (QL) integration framework was proposed for the selection of metaheuristic operators conducive to this balance, particularly the selection of binarization schemes when a continuous metaheuristic solves binary combinatorial problems. In this work the use of this framework is extended to other recent metaheuristics, demonstrating that the integration of QL in the selection of operators improves the exploration-exploitation balance. Specifically, the Whale Optimization Algorithm and the Sine-Cosine Algorithm are tested by solving the Set Covering Problem, showing statistical improvements in this balance and in the quality of the solutions.

scholarly journals A Mathematical Study of Barcelona Metro Network

Electronics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 557
Author(s):  
Irene Mariñas-Collado ◽  
Elisa Frutos Bernal ◽  
Maria Teresa Santos Martin ◽  
Angel Martín del Rey ◽  
Roberto Casado Vara ◽  
...  
Keyword(s):  
Clustering Analysis ◽  
Transportation Network ◽  
Point Of View ◽  
Statistical Point ◽  
Transport Services ◽  
Urban Public Transport ◽  
The Common ◽  
Subway Stations ◽  
Metro Network

The knowledge of the topological structure and the automatic fare collection systems in urban public transport produce many data that need to be adequately analyzed, processed and presented. These data provide a powerful tool to improve the quality of transport services and plan ahead. This paper aims at studying, from a mathematical and statistical point of view, the Barcelona metro network; specifically: (1) the structural and robustness characteristics of the transportation network are computed and analyzed considering the complex network analysis; and (2) the common characteristics of the different subway stations of Barcelona, based on the passenger hourly entries, are identified through hierarchical clustering analysis. These results will be of great help in planning and restructuring transport to cope with the new social conditions, after the pandemic.

scholarly journals Evaluation of Yield and Quality of Three Jackfruit (Artocarpus heterophyllus L.) Genotypes

2016 ◽  
Vol 14 (1) ◽  
pp. 107-111 ◽  
Author(s):  
M H Rahman ◽  
M M Alam Patwary ◽  
H Barua ◽  
S Nahar ◽  
Abu Noman Faruq Ahmmed
Keyword(s):  
Agricultural Research ◽  
Development Program ◽  
Yield Potential ◽  
Research Station ◽  
Maximum Weight ◽  
Yield And Quality ◽  
Maturity Period ◽  
Minimum Number ◽  
Overall Performance

Yield and quality performances of three jackfruit genotypes were studied at the Agricultural Research Station, Bangladesh Agricultural Research Institute, Pahartali, Chittagong during 2013-2014. Age, growth, maturity period, yield potential and also qualitative characteristics were compared among them.  Based on overall performance with respect to bearing potential, maturity period, fruit and bulb characters, the genotypes AHPah-1 have been found promising for table purpose followed by AHPah-2 and AHPah-3. Minimum days (117) to 1st harvest were observed in AHPah-1. The number of fruits per plant was exceedingly higher (73) in AHPah-1 whereas minimum number (41) was found in AHPah-2. Maximum weight (8.40 kg) per fruit was observed in AHPah-2 and minimum was in AHPah-1(3.40 kg).  The highest single fruit length (37.25cm) was found in AHPah-2 and breadth (27.00cm) was produced by AHPah-3. Maximum number of bulbs (116) was produced in AHPah-1, whereas minimum (63.00) was in AHPah-3. Maximum weight of bulbs per fruit (4.24 kg) was produced in AHPah-2. Individual bulb weight was higher (54.42g) in AHPah -2 whereas, the lowest (16.71) was in AHPah-1. Edible portion was higher (69.27%) in AHPah-1 whereas, the lowest (53.43%) was in AHPah-3. The TSS was the highest (21.00%) in AHPah-1. The highest bulb length and breadth was found in AHPah-3. Highest seeds weight (639g) was produced in AHPah-2. Individual seed weight (8.19 g) was higher in AHPah-2. Therefore, the genotypes can be included in the variety development program after comparing with the already BARI released jackfruit variety.The Agriculturists 2016; 14(1) 107-111

scholarly journals Set Covering Model in Solving Multiple Cutting Stock Problem

2020 ◽  
Vol 5 (4) ◽  
pp. 121
Author(s):  
Sisca Octarina ◽  
Devi Gusmalia Juita ◽  
Ning Eliyati ◽  
Putra Bahtera Jaya Bangun
Keyword(s):  
Column Generation ◽  
Pattern Generation ◽  
Cutting Stock Problem ◽  
Set Covering ◽  
Cutting Stock ◽  
Second Stage ◽  
Generation Technique ◽  
Cutting Pattern ◽  
Covering Model

Cutting Stock Problem (CSP) is the determination of how to cut stocks into items with certain cutting rules. A diverse set of stocks is called multiple stock CSP. This study used Pattern Generation (PG) algorithm to determine cutting pattern, then formulated it into a Gilmore and Gomory model and solved by using Column Generation Technique (CGT). Set Covering model was generated from Gilmore and Gomory model. Based on the results, selected cutting patterns in the first stage can be used in the second stage. The combination of patterns generated from Gilmore and Gomory model showed that the use of stocks was more effective than Set Covering model.  

scholarly journals Sustainable Location Selection of Data Centers: Developing a Multi-Criteria Set-Covering Decision-Making Methodology

2020 ◽  
Vol 19 (03) ◽  
pp. 741-773
Author(s):  
Siamak Kheybari ◽  
Mansoor Davoodi Monfared ◽  
Hadis Farazmand ◽  
Jafar Rezaei
Keyword(s):  
Data Center ◽  
Data Centers ◽  
Social Economic ◽  
Set Covering ◽  
Online Questionnaire ◽  
Location Selection ◽  
Sustainability Criteria ◽  
Proposed Model ◽  
Covering Model ◽  
Selection Of

In this paper, a multi-criteria set-covering methodology is proposed to select suitable locations for a set of data centers. First, a framework of criteria, with social, economic and environmental dimensions, is presented. The framework is used to calculate the suitability of potential data center locations in Iran. To that end, a sample of specialists in Iran was asked to take part in an online questionnaire, based on best–worst method (BWM), to determine the weight of the criteria included in the proposed framework, after which a number of potential locations are evaluated on the basis of the criteria. The proposed model is evaluated under a number of settings. Using the proposed multi-criteria set-covering model, not only the utility of candidate places is evaluated by sustainability criteria but also all service applicants are covered by at least one data center with a specific coverage radius.

scholarly journals Effects of seed tuber size on the yield and quality of seven accessions of potato

2019 ◽  
Vol 17 (2) ◽  
pp. 200-205
Author(s):  
Md. Murad Hossan Chowdhury ◽  
Md. Amirul Islam ◽  
Md. Atikuzzamman ◽  
Maria Akter Sathi ◽  
Sharmin Jahan
Keyword(s):  
Seed Tuber ◽  
Block Design ◽  
Average Diameter ◽  
Tuber Size ◽  
Stem Diameter ◽  
Large Size ◽  
Yield And Quality ◽  
Two Factors ◽  
Minimum Number

A field experiment was carried out at the Horticulture Farm, Bangladesh Agricultural University, Mymensingh during the period from November 2011 to February 2012 to study the effect of seed tuber size on the yield and quality of seven accessions of potato. The experiment was laid out in the Randomized Complete Block Design (RCBD) with three replications. This piece of research consisted of two factors namely, size of seed tubers i.e. three different size of seed tuber i.e. small (10-20 g), medium (21-30 g) and large (31-40 g) and seven accessions of potato i.e. AC10064, AC10076, AC10097, AC10109, AC10123, AC10190 and one check variety Cardinal. The size of individual plot was 1.8 m × 1.2 m. Two adjacent unit plots and blocks were separated by 0.5 m and 0.5 m. A spacing of 60 cm × 30 cm was also used in terms of planting. Data on different yield contributing characters and yield were recorded. The tallest plants were produced by the large size of seed tuber accession AC10109 (120.25 cm) which also took minimum time (6.10 days) to germinate and possessed maximum stem diameter (0.95 cm) while small seed tuber of Cardinal required maximum days (10.23 days) along with shortest height (60.22 cm) as well as stem diameter (0.65 cm). The large size seed tuber of accession AC10109 gave maximum number of main stems/hill (6.4) and small size of seed tuber variety Cardinal gave minimum number of main stems/hill (2.96). The large size of seed tuber accession AC10109 produced maximum number of compound leaves/hill (64.80) and the small size of seed tuber Cardinal produced minimum number of compound leaves/hill (35.74). In terms of yield character large size of seed tuber of AC10109 accession exhibited highest results in tuber number 9.60 with the average diameter of tubers (5.86 cm) and yield was 10.42 t/ha. The accessions differed significantly with respect to all the plant characters studied. J. Bangladesh Agril. Univ. 17(2): 200–205, June 2019

scholarly journals Hybrid Set Covering and Dynamic Modular Covering Location Problem: Application to an Emergency Humanitarian Logistics Problem

2020 ◽  
Vol 10 (20) ◽  
pp. 7110 ◽  
Author(s):  
Roghayyeh Alizadeh ◽  
Tatsushi Nishi
Keyword(s):  
Location Problem ◽  
Set Covering ◽  
Strategic Decisions ◽  
Maximal Covering ◽  
Planning Decisions ◽  
Tactical Decisions ◽  
Covering Model ◽  
Validation Tests ◽  
Capacitated Facilities

This paper presents an extension of the covering location problem as a hybrid covering model that utilizes the set covering and maximal covering location problems. The developed model is a multi-period model that considers strategic and tactical planning decisions. Hybrid covering location problem (HCLP) determines the location of the capacitated facilities by using dynamic set covering location problem as strategic decisions and assigns the constructive units of facilities and allocates the demand points by using dynamic modular capacitated maximal covering location problem as tactical decisions. One of the applications of the proposed model is locating first aid centers in humanitarian logistic services that have been addressed by studying a threat case study in Japan. In addition to validating the developed model, it has been compared to other possible combined problems, and several randomly generated examples have been solved. The results of the case study and model validation tests approve that the main hybrid developed model (HCLP) is capable of providing better coverage percentage compared to conventional covering models and other hybrid variants.

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