A Heuristic Algorithm for Solving a Large-scale Real-world Territory Design Problem

Omega ◽  
2021 ◽  
pp. 102442
Author(s):  
Lin Zhou ◽  
Lu Zhen ◽  
Roberto Baldacci ◽  
Marco Boschetti ◽  
Ying Dai ◽  
...  
Author(s):  
Fabian Lopez

Small geographic basic units (BU) are grouped into larger geographic territories on a Territory Design Problem (TDP). Proposed approach to solve a TDP is presented through a study case developed on a large soft drinks company which operates in the city of Monterrey, México. Each BU of our TDP is defined by three activity measures: (1) number of customers, (2) sales volume and (3) workload. Some geographic issues about contiguity and compactness for the territories to be constructed are considered. An optimal solution is obtained when the constructed territories are well balanced taking into consideration each activity measure simultaneously. In particular, contiguity is hard to be represented mathematically. All previous research work indicates that this NP-Hard problem is not suitable for solving on large-scale instances. A new strategy which is based on a hybrid-mixed integer programming (HMIP) approach is developed. Specifically, our implementation is based on a Cut-Generation Strategy. We take advantage from territory centers obtained through a relaxation of a P-median based model. This model has a very high degree of connectivity. Thus, small number of iterations to find connected solutions is required. The authors detail out their methodology and then they proceed to its computational implementation. Experimental results show the effectiveness of our method in finding near-optimal solutions for very large instances up to 10,000 BU’s in short computational times (less than 10 minutes). Nowadays, this model is being used by the firm with important economical benefits.


2006 ◽  
Vol 12 (1) ◽  
pp. 18-22
Author(s):  
Luca Coslovich ◽  
Raffaele Pesenti ◽  
Walter Ukovich

In this paper we consider large‐scale set partitioning problems. Our main purpose is to show that real‐world set partitioning problems originating from the container‐trucking industry are easier to tackle in respect to general ones. We show such different behavior through computational experiments: in particular, we have applied both a heuristic algorithm and some exact solution approaches to real‐world instances as well as to benchmark instances from Beasley OR‐library. Moreover, in order to gain an insight into the structure of the real-world instances, we have performed and evaluated various instance perturbations.


Diabetes ◽  
2020 ◽  
Vol 69 (Supplement 1) ◽  
pp. 1588-P ◽  
Author(s):  
ROMIK GHOSH ◽  
ASHOK K. DAS ◽  
AMBRISH MITHAL ◽  
SHASHANK JOSHI ◽  
K.M. PRASANNA KUMAR ◽  
...  

Diabetes ◽  
2020 ◽  
Vol 69 (Supplement 1) ◽  
pp. 2258-PUB
Author(s):  
ROMIK GHOSH ◽  
ASHOK K. DAS ◽  
SHASHANK JOSHI ◽  
AMBRISH MITHAL ◽  
K.M. PRASANNA KUMAR ◽  
...  

Author(s):  
С. Л. Подвальный ◽  
О. А. Сотникова ◽  
Я. А. Золотухина

Постановка задачи. В настоящее время формирование современной комфортной городской среды приобретает особое социально-экономическое значение и выдвигается в число приоритетных государственных масштабных программ. В связи с этим необходимо разработать концепцию благоустройства ключевого общественного пространства, а именно: определить основные и сопутствующие функции данной территории, создать эскизное предложение проекта благоустройства с учетом всех необходимых норм и стандартов, внедрить современные технологии. Результаты. Выполнен эскизный дизайн-проект «Аллеи архитекторов» по ул. Орджоникидзе г. Воронеж, включающий в себя основные элементы по зонированию территории, проектированию акцентных объектов и внедрению инновационных технологий «умного города», позволяющих повысить уровень комфорта горожан. Выводы. Благоустройство населенных мест приобретает особое значение в условиях дискомфорта среды. С выполнением комплекса мероприятий, направленных на благоустройство, и с внедрением современных технологий значительно улучшается экологическое состояние, внешний облик города. Оздоровление и модернизация среды, которая окружает человека в городе, благотворно влияет на психофизическое состояние, что особенно важно в период интенсивного роста городов. Statement of the problem. Currently the formation of the modern comfortable urban environment is gaining a special social and economic value and moving forward in the priorities of state large-scale programs. The purpose of development of the concept of improvement of public space is definition of the main and accompanying functions of this territory, design of the outline offer of the project of improvement considering all necessary norms and standards and implementation of modern technologies. Results. The conceptual project of “Alley of Architects” includes the basic elements of territory zoning, design of accent objects and implementation of technologies of a “smart-city”. These elements allow one to increase the level of comfort of inhabitants. Conclusions. Improvement of the inhabited places is of particular importance in the conditions of discomfort of the environment. Carrying out a complex of the actions directed to gardening and improvement, introducing modern technologies, the ecological condition, the physical appearance of the city considerably improves. Improvement and modernization of the environment which surrounds the person in the city influences a psychophysical state well that especially important during intensive growth of the cities.


2021 ◽  
Vol 51 (3) ◽  
pp. 9-16
Author(s):  
José Suárez-Varela ◽  
Miquel Ferriol-Galmés ◽  
Albert López ◽  
Paul Almasan ◽  
Guillermo Bernárdez ◽  
...  

During the last decade, Machine Learning (ML) has increasingly become a hot topic in the field of Computer Networks and is expected to be gradually adopted for a plethora of control, monitoring and management tasks in real-world deployments. This poses the need to count on new generations of students, researchers and practitioners with a solid background in ML applied to networks. During 2020, the International Telecommunication Union (ITU) has organized the "ITU AI/ML in 5G challenge", an open global competition that has introduced to a broad audience some of the current main challenges in ML for networks. This large-scale initiative has gathered 23 different challenges proposed by network operators, equipment manufacturers and academia, and has attracted a total of 1300+ participants from 60+ countries. This paper narrates our experience organizing one of the proposed challenges: the "Graph Neural Networking Challenge 2020". We describe the problem presented to participants, the tools and resources provided, some organization aspects and participation statistics, an outline of the top-3 awarded solutions, and a summary with some lessons learned during all this journey. As a result, this challenge leaves a curated set of educational resources openly available to anyone interested in the topic.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Seyed Hossein Jafari ◽  
Amir Mahdi Abdolhosseini-Qomi ◽  
Masoud Asadpour ◽  
Maseud Rahgozar ◽  
Naser Yazdani

AbstractThe entities of real-world networks are connected via different types of connections (i.e., layers). The task of link prediction in multiplex networks is about finding missing connections based on both intra-layer and inter-layer correlations. Our observations confirm that in a wide range of real-world multiplex networks, from social to biological and technological, a positive correlation exists between connection probability in one layer and similarity in other layers. Accordingly, a similarity-based automatic general-purpose multiplex link prediction method—SimBins—is devised that quantifies the amount of connection uncertainty based on observed inter-layer correlations in a multiplex network. Moreover, SimBins enhances the prediction quality in the target layer by incorporating the effect of link overlap across layers. Applying SimBins to various datasets from diverse domains, our findings indicate that SimBins outperforms the compared methods (both baseline and state-of-the-art methods) in most instances when predicting links. Furthermore, it is discussed that SimBins imposes minor computational overhead to the base similarity measures making it a potentially fast method, suitable for large-scale multiplex networks.


2021 ◽  
Vol 14 (7) ◽  
pp. 700
Author(s):  
Theodoros Mavridis ◽  
Christina I. Deligianni ◽  
Georgios Karagiorgis ◽  
Ariadne Daponte ◽  
Marianthi Breza ◽  
...  

Now more than ever is the time of monoclonal antibody use in neurology. In headaches, disease-specific and mechanism-based treatments existed only for symptomatic management of migraines (i.e., triptans), while the standard prophylactic anti-migraine treatments consist of non-specific and repurposed drugs that share limited safety profiles and high risk for interactions with other medications, resulting in rundown adherence rates. Recent advances in headache science have increased our understanding of the role of calcitonin gene relate peptide (CGRP) and pituitary adenylate cyclase-activating polypeptide (PACAP) pathways in cephalic pain neurotransmission and peripheral or central sensitization, leading to the development of monoclonal antibodies (mAbs) or small molecules targeting these neuropeptides or their receptors. Large scale randomized clinical trials confirmed that inhibition of the CGRP system attenuates migraine, while the PACAP mediated nociception is still under scientific and clinical investigation. In this review, we provide the latest clinical evidence for the use of anti-CGRP in migraine prevention with emphasis on efficacy and safety outcomes from Phase III and real-world studies.


Sign in / Sign up

Export Citation Format

Share Document