Comparing Mixed & Integer Programming vs. Constraint Programming by solving Job-Shop Scheduling Problems

Scheduling is a key factor for operations management as well as for business success. From industrial Job-shop Scheduling problems (JSSP), many optimization challenges have emerged since de 1960s when improvements have been continuously required such as bottlenecks allocation, lead-time reductions and reducing response time to requests.  With this in perspective, this work aims to discuss 3 different optimization models for minimizing Makespan. Those 3 models were applied on 17 classical problems of examples JSSP and produced different outputs.  The first model resorts on Mixed and Integer Programming (MIP) and it resulted on optimizing 60% of the studied problems. The other models were based on Constraint Programming (CP) and approached the problem in two different ways: a) model CP1 is a standard IBM algorithm whereof restrictions have an interval structure that fail to solve 53% of the proposed instances, b) Model CP-2 approaches the problem with disjunctive constraints and optimized 88% of the instances. In this work, each model is individually analyzed and then compared considering: i) Optimization success performance, ii) Computational processing time, iii) Greatest Resource Utilization and, iv) Minimum Work-in-process Inventory. Results demonstrated that CP-2 presented best results on criteria i and ii, but MIP was superior on criteria iii and iv and those findings are discussed at the final section of this work

Quality and safety conditions of flocked oats (Avena sativa L.) stored in bags: Poster

Oats (Avena sativa L.) have reached the healthy food market worldwide due to its special nutrients composition and fiber high quality. Therefore, quality & safety control is a must, both during the storage and commercialization stages. The current study evaluated the physicochemical characteristics (flakes size/variation %, pH, moisture content-mc, water activity-aw), living organisms (insects & mites / mycoflora - fungi load& genera identification), mycotoxins(ochratoxin A – OTA / zearalenone – ZON / aflatoxins – AFLs / esterigmatocistin – EST)andthe storage conditions of flocked oats stored inbags.Regarding the oats physicochemical characteristics, flakes particle size varied, however most of the samples present size uniformityand only one sample had high percentage of residue. That indicates high insects and other living organisms activity (consumption / proliferation) of oats starch and other nutrients. The analysis through stereomicroscope showed intense presence of insects and mites. Samples were seen also sheltering those living organisms (27%), which are not allowed by regulation (no soils, parasites and larvae presence). As expected, mc (10.8-13.2%) and/or aw (0.61-0.90) varied, however they kept on the safer levels (< 13% / 0.90) insects/mites and fungi growth wise. With respect to pH, it varied from4.1to 5.85, indicating some rancidity/fermentation reactions taking place, thus changes in organoleptic parameters. The total fungi load ranged from 3x102 to 1.29x105 CFU/g, with Aspergillus and Rhizopusthe genera more identified. Only one sample was toxin contaminated (OTA - 80 µg/kg). Insects are known vectors of fungal spores and can spread their hyphae on their dead/live skeleton, apart from mites that can trigger allergies in humans and animals. Therefore, current data demonstrate that despite the storage conditions control application, living organisms can occur in flocked oats (stored in bags) and it is necessary to apply decontamination methods to control/prevent their proliferation.Oats (Avena sativa L.) have reached the healthy food market worldwide due to its special nutrients composition and fiber high quality. Therefore, quality & safety control is a must, both during the storage and commercialization stages. The current study evaluated the physicochemical characteristics (flakes size/variation %, pH, moisture content-mc, water activity-aw), living organisms (insects & mites / mycoflora - fungi load& genera identification), mycotoxins(ochratoxin A – OTA / zearalenone – ZON / aflatoxins – AFLs / esterigmatocistin – EST)andthe storage conditions of flocked oats stored inbags.Regarding the oats physicochemical characteristics, flakes particle size varied, however most of the samples present size uniformityand only one sample had high percentage of residue. That indicates high insects and other living organisms activity (consumption / proliferation) of oats starch and other nutrients. The analysis through stereomicroscope showed intense presence of insects and mites. Samples were seen also sheltering those living organisms (27%), which are not allowed by regulation (no soils, parasites and larvae presence). As expected, mc (10.8-13.2%) and/or aw (0.61-0.90) varied, however they kept on the safer levels (< 13% / 0.90) insects/mites and fungi growth wise. With respect to pH, it varied from4.1to 5.85, indicating some rancidity/fermentation reactions taking place, thus changes in organoleptic parameters. The total fungi load ranged from 3x102 to 1.29x105 CFU/g, with Aspergillus and Rhizopusthe genera more identified. Only one sample was toxin contaminated (OTA - 80 µg/kg). Insects are known vectors of fungal spores and can spread their hyphae on their dead/live skeleton, apart from mites that can trigger allergies in humans and animals. Therefore, current data demonstrate that despite the storage conditions control application, living organisms can occur in flocked oats (stored in bags) and it is necessary to apply decontamination methods to control/prevent their proliferation

Differences in risk factors for incident and recurrent preterm birth: a population-based linkage of 3.5 million births from the CIDACS birth cohort.

BACKGROUND: Preterm birth (PTB) is a syndrome resulting from a complex list of underlying causes and factors, and whether these risk factors differ in the context of prior PTB history is less understood. The aim of this study was to explore whether PTB risk factors in a second pregnancy were different in women with versus without previous PTB. METHODS: We conducted a population-based cohort study using data from the birth cohort of the Center for Data and Knowledge Integration for Health (CIDACS) for the period 2001 to 2015. We used longitudinal transition models with multivariate logistic regression to investigate whether risk factors varied between incident and recurrent PTB. RESULTS: A total of 3,528,050 live births from 1,764,025 multiparous women were analyzed. We identified different risk factors (Pdifference <0.05) between incident and recurrent PTB. The following were associated with an increased chance for PTB incidence, but not recurrent: household overcrowding (OR 1.09), maternal race/ethnicity [(Black/mixed-OR 1.04) and (indigenous-OR 1.34)], young maternal age (14 to 19 years-OR 1.16), and cesarean delivery (OR 1.09). The following were associated with both incident and recurrent PTB, respectively: single marital status (OR 0.85 vs 0.90), reduced number of prenatal visits [(no visit-OR 2.56 vs OR 2.16) and (1 to 3 visits-OR 2.44 vs OR 2.24)], short interbirth interval [(12 to 23 months-OR 1.04 vs OR 1.22) and (<12 months, OR 1.89, 95 vs OR 2.58)], and advanced maternal age (35-49 years-OR 1.42 vs OR 1.45). For most risk factors, the point estimates were higher for incident PTB than recurrent PTB. CONCLUSIONS: The risk factors for PTB in the second pregnancy differed according to women's first pregnancy PTB status. The findings give the basis for the development of specific prevention strategies for PTB in a subsequent pregnancy

Evidence of contamination by oil and oil products in the Santos-Sao Vicente estuary, Sao Paulo, Brazil

Different components of the mixed function oxidase (MFO) system and the levels of fluorescent aromatic compounds in bile (FACs) were measured in Cathorops spixii in order to assess the impact of polycyclic aromatic hydrocarbons (PAHs). Fish were sampled in an estuary (Santos/Sao Vicente) with a history of contamination by PAHs, mainly due to the presence of the industrial complex of Cubatao city and of another of low anthropogenic influence (Cananeia) on the Brazilian coast. FACs were higher in fish from the polluted site, and the PAH 5 and 6-ring metabolites were the most frequent - with 14% and 15%, respectively. Levels of the different components of the MFO system showed the same variation profile as the FACs for both estuaries. Therefore, the values found for somatic indexes and biomarkers with data of bile PAH metabolites indicate the presence of organic contaminants, especially in the area subject to the influence of the industrial complex on the Santos/Sao Vicente estuary.CAPES (Brazilian Agency for Science and Technology); Oceanographic Institute of Sao Paulo University; Laboratory of Ecotoxicology and Environmental Chemistry of the University of Algarve; CAPES-PDEE [BEX 2176/07-6]info:eu-repo/semantics/publishedVersio