Industrial and Tramp Ship Routing Problems: Closing the Gap for Real-Scale Instances

Recent studies in maritime logistics have introduced a general ship routing problem and a benchmark suite based on real shipping segments, considering pickups and deliveries, cargo selection, ship-dependent starting locations, travel times and costs, time windows, and incompatibility constraints, among other features. Together, these characteristics pose considerable challenges for exact and heuristic methods, and some cases with as few as 18 cargoes remain unsolved. To face this challenge, we propose an exact branch-and-price (B&P) algorithm and a hybrid metaheuristic. Our exact method generates elementary routes, but exploits decremental state-space relaxation to speed up column generation, heuristic strong branching, as well as advanced preprocessing and route enumeration techniques. Our metaheuristic is a sophisticated extension of the unified hybrid genetic search. It exploits a set-partitioning phase and uses problem-tailored variation operators to efficiently handle all the problem characteristics. As shown in our experimental analyses, the B&P optimally solves 239/240 existing instances within one hour. Scalability experiments on even larger problems demonstrate that it can optimally solve problems with around 60 ships and 200 cargoes (i.e., 400 pickup and delivery services) and find optimality gaps below 1.04% on the largest cases with up to 260 cargoes. The hybrid metaheuristic outperforms all previous heuristics and produces near-optimal solutions within minutes. These results are noteworthy, since these instances are comparable in size with the largest problems routinely solved by shipping companies

The Vehicle Routing Problem with Service Level Constraints

We consider a vehicle routing problem which seeks to minimize cost subject to service level constraints on several groups of deliveries. This problem captures some essential challenges faced by a logistics provider which operates transportation services for a limited number of partners and should respect contractual obligations on service levels. The problem also generalizes several important classes of vehicle routing problems with profits. To solve it, we propose a compact mathematical formulation, a branch-and-price algorithm, and a hybrid genetic algorithm with population management, which relies on problem-tailored solution representation, crossover and local search operators, as well as an adaptive penalization mechanism establishing a good balance between service levels and costs. Our computational experiments show that the proposed heuristic returns very high-quality solutions for this difficult problem, matches all optimal solutions found for small and medium-scale benchmark instances, and improves upon existing algorithms for two important special cases: the vehicle routing problem with private fleet and common carrier, and the capacitated profitable tour problem. The branch-and-price algorithm also produces new optimal solutions for all three problems

Improved bounds for large scale capacitated arc routing problem

AbstractThe Capacitated Arc Routing Problem (CARP) stands among the hardest combinatorial problems to solve or to find high quality solutions. This becomes even more true when dealing with large instances. This paper investigates methods to improve on lower and upper bounds of instances on graphs with over 200 vertices and 300 edges, dimensions that, today, can be considered of large scale. On the lower bound side, we propose to explore the speed of a dual ascent heuristic to generate capacity cuts. These cuts are next improved with a new exact separation enchained to the linear program resolution that follows the dual heuristic. On the upper bound, we implement a modified Iterated Local Search procedure to Capacitated Vehicle Routing Problem (CVRP) instances obtained by applying a transformation from the CARP original instances. Computational experiments were carried out on the set of large instances generated by Brandão and Eglese and also on the regular size sets. The experiments on the latter allow for evaluating the quality of the proposed solution approaches, while those on the former present improved lower and upper bounds for all instances of the corresponding set

Cartas na manga : o circo como conteúdo na educação física infantil

Esse estudo narrativo e autobiográfico aprofunda as aprendizagens construídas ao longo do Estágio de Docência em Educação Física na Educação Infantil. O trabalho foi realizado em uma escola pública de Porto Alegre durante o segundo semestre de 2015 com uma turma de Jardim A que comportava crianças entre quatro e cinco anos de idade. A temática escolhida para ser trabalhada nas aulas de Educação Física foi o Circo, devido a sua abrangência de possibilidade de práticas corporais e da sua aceitação por crianças dessa faixa etária. Nesse relato reflexivo, encontro elementos pedagógicos que foram relevantes a minha prática e os relaciono com as teorias de ensino para essa faixa etária. O trabalho também descreve a rotina escolar e como ela tem influência nas aulas de educação física. O ensino das práticas circenses é descrito não como uma opção pedagógica aonde o aprendizado é focado na técnica em si. No lugar disso, as crianças são estimuladas a vivenciarem e se sentirem parte do universo circense. Dessa maneira coloco também a maneira lúdica como abordei o tema e a influência que o conteúdo teve sobre a minha formação como professor. Por fim, nas conclusões reflito sobre como o Circo teve uma boa aceitação da turma e se mostrou uma excelente estratégia pedagógica para as aulas de Educação Física Infantil nessa experiência. Ele também contribuiu de maneira significativa para a que eu explorasse estratégias pedagógicas que complementassem a minha formação.The final paper is a report from my own experience in the obligatory discipline of lecturing in Child Education. The work took place in a public school in Porto Alegre during the second semester of 2015 with a class of preschoolers aging between 4 and 5 years old. The chosen theme of the Physical Education classes was the circus, due to its range of possibilities of corporal activities and due to its acceptance by the children. In this reflective analysis, I found elements of teaching methodology that were essential to my activity and related them with teaching theories for children of such age. The paper also describes my scholar routine and how it influences on Physical Education classes. The circus activities are not described as a pedagogical option itself for the acquisition of technical movements. Instead, the students are stimulated to experience and to feel part of the circus universe. In this manner I also describe the playful way of which I approached the theme and how it had influence over my formation as a teacher. At last, I reflect in my conclusions about how the circus had a good acceptance in class and ended up becoming a great pedagogical strategy for Physical Education classes for children in this experience. It also had a significant role in my out coming as a teacher

Arc Routing with Time-Dependent Travel Times and Paths

Vehicle routing algorithms usually reformulate the road network into a complete graph in which each arc represents the shortest path between two locations. Studies on time-dependent routing followed this model and therefore defined the speed functions on the complete graph. We argue that this model is often inadequate, in particular for arc routing problems involving services on edges of a road network. To fill this gap, we formally define the time-dependent capacitated arc routing problem (TDCARP), with travel and service speed functions given directly at the network level. Under these assumptions, the quickest path between locations can change over time, leading to a complex problem that challenges the capabilities of current solution methods. We introduce effective algorithms for preprocessing quickest paths in a closed form, efficient data structures for travel time queries during routing optimization, as well as heuristic and exact solution approaches for the TDCARP. Our heuristic uses the hybrid genetic search principle with tailored solution-decoding algorithms and lower bounds for filtering moves. Our branch-and-price algorithm exploits dedicated pricing routines, heuristic dominance rules and completion bounds to find optimal solutions for problem counting up to 75 services. Based on these algorithms, we measure the benefits of time-dependent routing optimization for different levels of travel-speed data accuracy

Arma de fogo desmuniciada: as divergências jurídicas quanto ao tipo de delito cometido

Trabalho de Conclusão de Curso, apresentado como requisito parcial para obtenção do grau de Bacharel no curso de Direito da Universidade do Extremo Sul Catarinense, UNESC.O atual entendimento do Supremo Tribunal Federal entende que a infração do porte de arma de fogo desmuniciada, descrito no art. 14 da Lei. n.º 10.826/03 trata-se de crime de perigo abstrato, o que altera a posição amplamente divulgada até então, pois agora, passa a considerar irrelevantes as circunstâncias da eficácia da arma, se municiada ou não, e de se encontrar à disposição do agente para pronto uso, ou não. O atual entendimento proferido pelo Egrégio gera muitas discussões, visto que nos delitos de perigo abstrato, este é presumido pelo legislador, não se permitindo prova contrária, cujo somente a mera conduta já dispensa a demonstração de que a vítima ficou exposta a uma situação concreta de risco, porém, a esta regra cabem exceções, compreendidas pelo principio da ofensividade, que atualmente está sendo desconsiderado, e junto com esta desconsideração está se excluindo também o chamado crime impossível. Sendo, portanto de grande importância um estudo mais aprofundado sobre o tema, já que a atual decisão do Supremo Tribunal Federal gerou muitas divergências jurídicas, o que reflete diretamente na sociedade

Upsilon \bar BB Couplings, Slope of the Isgur-Wise Function and Improved Estimate of \boldmath{V_{cb}$}}

We estimate the sum of the $\Upsilon \bar BB$ couplings using QCD Spectral Sum Rules (QSSR). Our result implies the phenomenological bound $\xi'(vv'=1) \geq -1.04$ for the slope of the Isgur-Wise function. An analytic estimate of the (physical) slope to two loops within QSSR leads to the accurate value $\xi'(vv'=1) \simeq -(1.00 \pm 0.02)$ due to the (almost) complete cancellations between the perturbative and non-perturbative corrections at the stability points. Then, we deduce, from the present data, the improved estimate \vert V_{cb} \vert \simeq \ga 1.48 \mbox{ps}/\tau_B \dr ^{1/2}(37.3 \pm 1.2 \pm 1.4)\times 10^{-3} where the first error comes from the data analysis and the second one from the different model parametrizations of the Isgur-Wise function.Comment: {{\bf $\bf 10 pages, Latex, (1 Figure on request), CERN-TH-7103/93 (Phys. Lett. B in press

Cobertura de equipes de saúde bucal na Estratégia Saúde da Família e uso de serviços odontológicos em adolescentes de Mato Grosso do Sul, 2019: estudo transversal

Objective: To analyze the association between the coverage of oral health teams in the Family Health Strategy (ESF-SB) and the use of dental services among adolescents aged 12 years in Mato Grosso do Sul, 2019. Methods: This is a cross-sectional study, involving school-based research. The outcome was the use of dental services. Structural equation models were performed to test the association of covariates with the use of services. Results: Of the 615 participants, 74.0% used dental services in the past three years. ESF-SB coverage ≥50% was associated with greater use of public dental services [Standardized Coefficient (SC) = 0.10 – IC95% 0.01;0.18], greater use for treatment (SC = -0.07 – IC95% 0.17;0.01), and greater consumption of unhealthy foods (SC = 0.19 – IC95% 0.11;0.26). Conclusion: Greater coverage of ESF-SB was associated with greater use for treatments and greater inadequate food consumption by adolescents. Oral health teams must organize access and qualify the work process.Objetivo: Analisar a associação entre a cobertura de equipes de saúde bucal na Estratégia Saúde da Família (ESF-SB) e a utilização de serviços odontológicos entre adolescentes de 12 anos, em Mato Grosso do Sul, Brasil, 2019. Métodos: Trata-se de um estudo transversal, cujo desfecho foi a utilização de serviços odontológicos. Modelos de equações estruturais foram construídos para testar a associação das covariáveis com o desfecho. Resultados: Dos 615 participantes, 74,0% utilizaram os serviços odontológicos nos últimos três anos. A cobertura de ESF-SB ≥50% associou-se a maior uso de serviços públicos [coeficiente padronizado (CP) = 0,10 – IC95% 0,01;0,18], menor uso para prevenção (CP = -0,07 – IC95% -0,17;0,01) e maior consumo de alimentos não saudáveis (CP = 0,19 – IC95% 0,11;0,26). Conclusão: Maiores coberturas de ESF-SB associaram-se a menor utilização de serviços para prevenção e maior consumo alimentar não saudável. As equipes devem organizar o acesso e qualificar o processo de trabalho

Light Quark Masses 99

I give a short historical and a critical review of the determinations of light quark masses from QCD at dawn of the next millennium. QCD spectral sum rules combined with ChPT give, to order $\alpha_s^3$, the world average for the running masses: $\bar{m}_s$(2 GeV)= $(118.9\pm 12.2)$ MeV, $\bar{m}_d(2~{GeV})=(6.3\pm 0.8)$ MeV, $\bar{m}_u(2~{GeV})=(3.5\pm 0.4)$ MeV and the corresponding values of the invariant masses given in Eq. 24. Lower and upper bounds derived from the positivity of spectral moments are presented in Tables 2 and 3. For a comparison, we critically review the recent lattice results (section 8 and Table 5) and attempt to deduce the present {\it QCD grand average} determination (Table 6): $\bar{m}_s$(2 GeV)= $(110.9\pm 8.8)$ MeV, to be used with a great care. Then, we deduce the value: $B_6^{1/2}-0.45(\rm resp.~0.32)B_8^{3/2}\simeq 1.6\pm 0.4~(\rm resp.~1.1\pm 0.3)$ and the lower bound $1.1\pm 0.2$ (resp. $0.7\pm 0.1$), for the combination of the penguin operators, governing the CP-violating parameters $\epsilon'/\epsilon$ without (resp. with) the inclusion of the final state interaction effects. The result signals a possible deviation from the leading 1/N prediction by about $1\sim 3\sigma$, which should be tested using accurate non-perturbative calculations.Comment: Latex2e two-column 13 pages 5 Tables + 1 figure. Review talk given at QCD 99 (Montpellier 7-13th July 1999) and plenary talk at QCD Confinement 2000 (Osaka 7-10th March 2000) Report-n0: Montpellier preprint PM/99-50. Updated version and application to epsilon'/epsilo