The Impact of Implied Constraints on MaxSAT B2B Instances

The B2B scheduling optimization problem consists of finding a schedule of a set of meetings between pairs of participants, minimizing their number of idle time periods. Recent works have shown that SAT-based approaches are state-of-the-art on this problem. One interesting feature of such approaches is the use of implied constraints. In this work, we provide an experimental setting to study the impact of using these implied constraints in MaxSAT B2B instances. To this purpose and due to the reduced number of existing real-world B2B instances, we propose a random B2B instance generation model, which reproduces certain features of these problems. In our experimental analysis, we show that the impact of using some implied constraints in the MaxSAT encodings depends on the characteristics of the problem, and we also analyze the benefits of combining them. Finally, we give some insights on how a MaxSAT solver is able to exploit these implied constraints.Spanish Government RTI2018-095609-B-I00French National Research Agency (ANR) ANR-19-CHIA-0013-01Juan de la Cierva program - MCIN IJC2019040489-IAE

Estudi de noves varietats de mongeta pel seu ús com a mongeta tendra

The green bean (Phaseolus vulgaris L.) depending on the variety shows different types of growth, being the most important of them the determinate growth (type I) and the undetermined growth habit (type IV). This fact makes the production costs fluctuate, because a cultivation with determinate plants require less labor in comparison to one with undetermined plants, and so the production costs are lower. Nowadays, the farmers use a variety with a high agronomic and sensorial value but this variety have an undetermined growth habit, which leads us to obtain a material, which its final price is less competitive than varieties cultivated outside Catalonia. The objective of this work is to obtain a variety that adjusts to the idiotype proposed by thy farmers, which include a new variety with determinate growth habit. Varieties selected from a commercial germoplasm research process have been agro-morphologically and sensory characterized. With the results obtained, on one hand, it has been possible to check the possibility of finding a variety in the market that adjusts to the proposed idiotype. On the other hand, it has enabled us to select the varieties that will allow us to start the genetic improvement program in order to introduce the fin gen (determinate growth gen). To sensory characterize the candidates, a new cooking protocol for the green been has been developed and a new tasting panel which incorporates characteristics attributes from the green bean was created. Finally, during the characterization process, we made the crossings of the first generation from the selected varieties of the improvement program.La mongeta tendra (Phaseolus vulgaris L.) presenta, segons la varietat, diferents tipus de creixement, els més importants són el determinat (mata baixa) i el indeterminat (mata alta). Aquest aspecte fa variar molt els costos de producció, ja que les varietats de mata baixa requereixen molta menys mà d'obra en comparació amb les de mata alta, i per tant, els costos de producció són molt inferiors. Actualment els agricultors disposen d'una varietat de gran valor agronòmic i sensorial però de creixement indeterminat, fet que provoca que el preu final del producte, sigui poc competitiu amb material vingut de fora de Catalunya. Per aquest motiu, l'objectiu d'aquest treball és l'obtenció d'una varietat que s'ajusti a l'idiotip proposat pels agricultors, que inclou el creixement determinat de la nova varietat. S'han caracteritzat agromorfològica i sensorialment varietats sorgides d'un procés de recerca de germoplasma comercial. Amb aquestes dades, s'ha descartat la possibilitat que en el mercat existís una varietat que s'ajustés a l'idiotip proposat i per altra banda ha permès seleccionar les varietats amb les quals s'iniciarà el programa de millora per tal d'introduir el gen fin (donador de creixement determinat) en aquelles varietats de mata alta que presentin característiques agromorfològiques i sensorials pròximes a l'idiotip Per tal de caracteritzar sensorialment les varietats candidates s'ha desenvolupat un protocol de cocció per mongeta tendre i alhora s'ha creat la fitxa de tast que incorpora el atributs característics de la mongeta tendre. Finalment s'han realitzat els encreuaments de la primera generació de selecció del programa de millora d'aquelles varietats seleccionades durant el procés de caracterització.La judía verde (Phaseolus vulgaris L.) presenta, según la variedad, diferentes tipos de crecimiento, los más importantes son el determinado (mata baja) y el indeterminado (mata alta). Este aspecto hace variar mucho los costes de producción, ya que las variedades de mata baja requieren mucha menos mano de obra en comparación con las de mata alta, y por lo tanto, los costes de producción son muy inferiores. Actualmente los agricultores disponen de una variedad de gran valor agronómico y sensorial pero de crecimiento indeterminado, hecho que provoca que el precio final del producto, sea poco competitivo con el material procedente de fuera de Cataluña. Por este motivo, el objetivo de este trabajo es la obtención de una variedad que se ajuste al ideotipo propuesto por los agricultores, que incluye el crecimiento determinado de la nueva variedad. Se han caracterizado agromorfológica y sensorialmente variedades que han surgido de un proceso de búsqueda de germoplasma comercial. Con estos datos, se ha descartado la posibilidad que en el mercado existiera una variedad que se ajustara al ideotipo propuesto y por otro bando ha permitido seleccionar las variedades con las cuales se iniciará el programa de mejora para introducir el gen fin (donador de crecimiento determinado) en aquella variedades cuyas características agromorfológicas y sensoriales se aproximen al ideotipo. Por tal de caracterizar sensorialmente las variedades candidatas se ha desarrollado un protocolo de cocción para judía verde y a la vez se ha creado la ficha de cata que incorpora los atributos característicos de la judía verde. Finalmente se ha realizado los cruzamientos de la primera generación de selección del programa de mejora de las variedades seleccionadas durante el proceso de caracterización

The Complexity of 3-Valued Lukasiewicz Rules

It is known that determining the satisfiability of n-valued Łukasiewicz rules is NP-complete for n ≥ 4, as well as that it can be solved in time linear in the length of the formula in the Boolean case (when n = 2). However, the complexity for n = 3 is an open problem. In this paper we formally prove that the satisfiability problem for 3-valued Łukasiewicz rules is NP-complete. Moreover, we also prove that when the consequent of the rule has at most one element, the problem is polynomially solvable. © Springer International Publishing Switzerland 2015.Research partially supported by the Generalitat de Catalunya grant AGAUR 2014-SGR-118, and the Ministerio de Economía y Competividad projects AT CONSOLIDER CSD2007-0022, INGENIO 2010, CO-PRIVACY TIN2011-27076-C03-03, EDETRI TIN2012-39348-C02-01 and HeLo TIN2012-33042. The second author was supported by Mobility Grant PRX14/00195 of the Ministerio de Educación, Cultura y DeportePeer reviewe

Automatic Proving of Fuzzy Formulae with Fuzzy Logic Programming and SMT

In this paper we deal with propositional fuzzy formulae containing severalpropositional symbols linked with connectives defined in a lattice of truth degrees more complex than Bool. We firstly recall an SMT (Satisfiability Modulo Theories) based method for automatically proving theorems in relevant infinitely valued (including Łukasiewicz and G¨odel) logics. Next, instead of focusing on satisfiability (i.e., proving the existence of at least one model) or unsatisfiability, our interest moves to the problem of finding the whole set of models (with a finite domain) for a given fuzzy formula. We propose an alternative method based on fuzzy logic programming where the formula is conceived as a goal whose derivation tree contains on its leaves all the models of the original formula, by exhaustively interpreting each propositional symbol in all the possible forms according the whole setof values collected on the underlying lattice of truth-degrees

Enzymatic synthesis of vanillin catalysed by an eugenol oxidase

Vanillin is one of the most important flavours produced in the world. Due to its increasing value and its demand, mainly in the food industry, several ways to obtain it at lower prices are under study. One of the routes is based on the oxidation of vanillyl alcohol by Eugenol oxidase (EUGO), which has high potential to be used at industrial scale owing to the high space time yields that can be obtained at lab scale (2.9 g L−1 h−1 of vanillin). Additionally, EUGO can be immobilised efficiently onto different supports (MANA-agarose, Epoxy-agarose and Purolite 8204F) which can be reused several times to perform the oxidation preserving good stability and improving more than 3-fold the biocatalyst yield

Implementation of the K-Means Algorithm on Heterogeneous Devices: A Use Case Based on an Industrial Dataset

This paper presents and analyzes a heterogeneous implementation of an industrial use case based on K-means that targets symmetric multiprocessing (SMP), GPUs and FPGAs. We present how the application can be optimized from an algorithmic point of view and how this optimization performs on two heterogeneous platforms. The presented implementation relies on the OmpSs programming model, which introduces a simplified pragma-based syntax for the communication between the main processor and the accelerators. Performance improvement can be achieved by the programmer explicitly specifying the data memory accesses or copies. As expected, the newer SMP+GPU system studied is more powerful than the older SMP+FPGA system. However the latter is enough to fulfill the requirements of our use case and we show that uses less energy when considering only the active power of the execution.This work is partially supported by the European Union H2020 project AXIOM (grant agreement n. 645496), HiPEAC (grant agreement n. 687698), and Mont-Blanc (grant agreements n. 288777, 610402 and 671697), the Spanish Government Programa Severo Ochoa (SEV-2015-0493), the Spanish Ministry of Science and Technology (TIN2015- 65316-P) and the Departament d’Innovació, Universitats i Empresa de la Generalitat de Catalunya, under project MPEXPAR: Models de Programaci´o i Entorns d’Execució Paral·lels (2014-SGR-1051).Peer ReviewedPostprint (author's final draft

Relaxing non-interference requirements in parallel plans

Funding: UK EPSRC (EP/P015638/1).The aim of being able to reason about quantities, time or space has been the main objective of the many efforts on the integration of propositional planning with extensions to handle different theories. Planning modulo theories (PMTs) are an approximation inspired by satisfiability modulo theories (SMTs) that generalize the integration of arbitrary theories with propositional planning. Parallel plans are crucial to reduce plan lengths and hence the time needed to reach a feasible plan in many approaches. Parallelization of actions relies on the notion of (non-)interference, which is usually determined syntactically at compile time. In this paper we define a semantic notion of interference between actions in PMT. Apart from being strictly stronger than any syntactic notion of interference, we show how semantic interference can be easily and efficiently checked by calling an off-the-shelf SMT solver at compile time, constituting a technique orthogonal to the solving method.Publisher PDFPeer reviewe

Application Acceleration on FPGAs with OmpSs@FPGA

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.OmpSs@FPGA is the flavor of OmpSs that allows offloading application functionality to FPGAs. Similarly to OpenMP, it is based on compiler directives. While the OpenMP specification also includes support for heterogeneous execution, we use OmpSs and OmpSs@FPGA as prototype implementation to develop new ideas for OpenMP. OmpSs@FPGA implements the tasking model with runtime support to automatically exploit all SMP and FPGA resources available in the execution platform. In this paper, we present the OmpSs@FPGA ecosystem, based on the Mercurium compiler and the Nanos++ runtime system. We show how the applications are transformed to run on the SMP cores and the FPGA. The application kernels defined as tasks to be accelerated, using the OmpSs directives are: 1) transformed by the compiler into kernels connected with the proper synchronization and communication ports, 2) extracted to intermediate files, 3) compiled through the FPGA vendor HLS tool, and 4) used to configure the FPGA. Our Nanos++ runtime system schedules the application tasks on the platform, being able to use the SMP cores and the FPGA accelerators at the same time. We present the evaluation of the OmpSs@FPGA environment with the Matrix Multiplication, Cholesky and N-Body benchmarks, showing the internal details of the execution, and the performance obtained on a Zynq Ultrascale+ MPSoC (up to 128x). The source code uses OmpSs@FPGA annotations and different Vivado HLS optimization directives are applied for acceleration.This work is partially supported by the European Union H2020 program through the EuroEXA project (grant 754337), and HiPEAC (GA 687698), by the Spanish Government through Programa Severo Ochoa (SEV-2015- 0493), by the Spanish Ministry of Science and Technology (TIN2015-65316-P) and the Departament d’Innovació Universitats i Empresa de la Generalitat de Catalunya, under project MPEXPAR: Models de Programació i Entorns d’Execució Paral·lels (2014-SGR-1051).Peer ReviewedPostprint (author's final draft

L'Elecció de centre escolar a Catalunya : elements per a un debat

Seminari Elecció de centre escolar celebrat a Can Bordoi els dies 9 i 10 de setembre de 2008Aquesta Finestra Oberta és fruit dels debats i deltreball realitzat en el marc del Seminari Internacional sobre Elecció de Centre Escolar que va tenir lloc els dies 9 i 10 de setembre de 2008 a Can Bordoi, i que va comptar amb la participació d'una trentena de per sones, entre les quals hi havia responsables d'administracions i organismes municipals i del Departament d'Educació; investigadors i professors universitaris; associacions de mares i pares; patronals del sector educatiu concertat, i persones d'altres organismes de la comunitat educativa del país