Compliment de les directrius DRIVER dels repositoris cooperatius RACO, RECERCAT i TDX

Aquest informe ha estat elaborat per encàrrec del Consorci de Biblioteques Universitàries de Catalunya (CBUC). El seu objectiu és comprovar si des del punt de vista tècnic, els repositoris cooperatius que el CBUC coordina juntament amb el Centre de Supercomputació de Catalunya (CESCA), es poden integrar dins la infrastructura DRIVER.

Driver scheduling problem modelling

The Drivers Scheduling Problem (DSP) consists of selecting a set of duties for vehicle drivers, for example buses, trains, plane or boat drivers or pilots, for the transportation of passengers or goods. This is a complex problem because it involves several constraints related to labour and company rules and can also present different evaluation criteria and objectives. Being able to develop an adequate model for this problem that can represent the real problem as close as possible is an important research area.The main objective of this research work is to present new mathematical models to the DSP problem that represent all the complexity of the drivers scheduling problem, and also demonstrate that the solutions of these models can be easily implemented in real situations. This issue has been recognized by several authors and as important problem in Public Transportation. The most well-known and general formulation for the DSP is a Set Partition/Set Covering Model (SPP/SCP). However, to a large extend these models simplify some of the specific business aspects and issues of real problems. This makes it difficult to use these models as automatic planning systems because the schedules obtained must be modified manually to be implemented in real situations. Based on extensive passenger transportation experience in bus companies in Portugal, we propose new alternative models to formulate the DSP problem. These models are also based on Set Partitioning/Covering Models; however, they take into account the bus operator issues and the perspective opinions and environment of the user.We follow the steps of the Operations Research Methodology which consist of: Identify the Problem; Understand the System; Formulate a Mathematical Model; Verify the Model; Select the Best Alternative; Present the Results of theAnalysis and Implement and Evaluate. All the processes are done with close participation and involvement of the final users from different transportation companies. The planner s opinion and main criticisms are used to improve the proposed model in a continuous enrichment process. The final objective is to have a model that can be incorporated into an information system to be used as an automatic tool to produce driver schedules. Therefore, the criteria for evaluating the models is the capacity to generate real and useful schedules that can be implemented without many manual adjustments or modifications. We have considered the following as measures of the quality of the model: simplicity, solution quality and applicability. We tested the alternative models with a set of real data obtained from several different transportation companies and analyzed the optimal schedules obtained with respect to the applicability of the solution to the real situation. To do this, the schedules were analyzed by the planners to determine their quality and applicability. The main result of this work is the proposition of new mathematical models for the DSP that better represent the realities of the passenger transportation operators and lead to better schedules that can be implemented directly in real situations.

Metaheuristics for the bus-driver scheduling problem

We present new metaheuristics for solving real crew scheduling problemsin a public transportation bus company. Since the crews of thesecompanies are drivers, we will designate the problem by the bus-driverscheduling problem. Crew scheduling problems are well known and severalmathematical programming based techniques have been proposed to solvethem, in particular using the set-covering formulation. However, inpractice, there exists the need for improvement in terms of computationalefficiency and capacity of solving large-scale instances. Moreover, thereal bus-driver scheduling problems that we consider can present variantaspects of the set covering, as for example a different objectivefunction, implying that alternative solutions methods have to bedeveloped. We propose metaheuristics based on the following approaches:GRASP (greedy randomized adaptive search procedure), tabu search andgenetic algorithms. These metaheuristics also present some innovationfeatures based on and genetic algorithms. These metaheuristics alsopresent some innovation features based on the structure of the crewscheduling problem, that guide the search efficiently and able them tofind good solutions. Some of these new features can also be applied inthe development of heuristics to other combinatorial optimizationproblems. A summary of computational results with real-data problems ispresented.

Driver costs in small firms: Empirical analysis for farms

The agricultural sector has always been characterized by a predominance of small firms. International competition and the consequent need for restraining costs are permanent challenges for farms. This paper performs an empirical investigation of cost behavior in agriculture using panel data analysis. Our results show that transactions caused by complexity influence farm costs with opposite effects for specific and indirect costs. While transactions allow economies of scale in specific costs, they significantly increase indirect costs. However, the main driver for farm costs is volume. In addition, important differences exist for small and big farms, since transactional variables significantly influence the former but not the latter. While sophisticated management tools, such ABC, could provide only limited complementary useful information but no essential allocation bases for farms, they seem inappropriate for small farms

Driver costs in small firms: Empirical analysis for farms

The agricultural sector has always been characterized by a predominance of small firms. International competition and the consequent need for restraining costs are permanent challenges for farms. This paper performs an empirical investigation of cost behavior in agriculture using panel data analysis. Our results show that transactions caused by complexity influence farm costs with opposite effects for specific and indirect costs. While transactions allow economies of scale in specific costs, they significantly increase indirect costs. However, the main driver for farm costs is volume. In addition, important differences exist for small and big farms, since transactional variables significantly influence the former but not the latter. While sophisticated management tools, such ABC, could provide only limited complementary useful information but no essential allocation bases for farms, they seem inappropriate for small farms

Disseny de drivers per a targes de transmissió de senyals

L'objectiu del projecte és poder configurar dues targetes que s'instal∙laran al Sincrotró ALBA. Per a això s'ha desenvolupat un driver per a Linux i una interfície gràfica (GUI). Com a introducció a les targetes, la memòria descriu el Sincrotró, i més específicament el sistema de sincronització (timing) on aquestes s'utilitzaran. També descriu el disseny dels drivers per a Linux2.6 i de la GUI, escrita utilitzant el llenguatge Python amb el framework Qt. Finalment, a la memòria s'exposen els problemes i solucions trobats durant la fase de validació del correcte funcionament de les plaques i dels diferents components del projecte.

Construcció d’un microrobot

Treball de recerca realitzat per un alumne d’ensenyament secundari i guardonat amb un Premi CIRIT per fomentar l'esperit científic del Jovent l’any 2006. La construcció d'un microrobot autònom capaç de realitzar una funció per ell mateix, ha permès exposar una introducció en el món de l'electrònica i la mecànica pràctiques. Es tracta d’un microrobot rastrejador: capaç de seguir una línia pintada al terra, per mitjà d'unes entrades (sensors detectors de llum), una lògica (C.I. operacionals) i uns motors motrius comandats per mitjà d'un C.I. driver. S’adjunten imatges dels resultats.

Learning from Shocks and the Decision to Open

Two claims pervade the literature on the political economy of market reforms: that economic crises cause reforms; and that crises matter because they bring into question the validity of the economic model held to be responsible for them. Economic crises are said to spur a process of learning that is conducive to the abandonment of failing models and to the adoption of successful models. But although these claims have become the conventional wisdom, they have been hardly tested empirically due to the lack of agreement on what constitutes a crisis and to difficulties in measuring learning from them. I propose a model of rational learning from experience and apply it to the decision to open the economy. Using data from 1964 through 1990, I show that learning from the 1982 debt crisis was relevant to the first wave of adoption of an export promotion strategy, but learning was conditional on the high variability of economic outcomes in countries that opened up to trade. Learning was also symbolic in that the sheer number of other countries that liberalized was a more important driver of others’ decisions to follow suit.

Sistema de comunicació sense fils utilitzant Zigbee per PDA

En aquest projecte es presenta el disseny i desenvolupament d'un conjunt d'interfícies per a un sistema de comunicació basat en l'estàndard Zigbee. El sistema està composat per una tarja que integra el mòdul Zigbee, un microcontrolador i una FPGA, que es vol controlar des d'un sistema Pocket PC a través del port SD. La implementació consta d’un driver SDIO per Windows CE 4.2, el controlador SDIO a la FPGA i l'enllaç de comunicació entre la FPGA i el microcontrolador.

A priori ratemaking using bivariate poisson regression models

In automobile insurance, it is useful to achieve a priori ratemaking by resorting to gene- ralized linear models, and here the Poisson regression model constitutes the most widely accepted basis. However, insurance companies distinguish between claims with or without bodily injuries, or claims with full or partial liability of the insured driver. This paper exa- mines an a priori ratemaking procedure when including two di®erent types of claim. When assuming independence between claim types, the premium can be obtained by summing the premiums for each type of guarantee and is dependent on the rating factors chosen. If the independence assumption is relaxed, then it is unclear as to how the tari® system might be a®ected. In order to answer this question, bivariate Poisson regression models, suitable for paired count data exhibiting correlation, are introduced. It is shown that the usual independence assumption is unrealistic here. These models are applied to an automobile insurance claims database containing 80,994 contracts belonging to a Spanish insurance company. Finally, the consequences for pure and loaded premiums when the independence assumption is relaxed by using a bivariate Poisson regression model are analysed.

Does Internationalization Alter the R&D-Productivity Relationship?

R&D investment is an important driver of productivity gains. However, firms differ in their ability to appropiate the returns to their R&D efforts. This paper analyses to what extent firm's internationalization influences the endogenous relation between R&D and productivity. In particular, we assess the contribution of R&D to productivity for a panel of UK firms that differ in their degree of internationalization. We find that, on average, multinationals obtain higher gains from their investment in R&D. However, the influence of internationalization on the contribution of R&D to productivity varies along the distribution of the returns to R&D. Keywords: R&D, Multinationals, Productivity. JEL Codes: C14, D24, F23.

Simulador de conducció enfocat a la investigació

El desenvolupament de sistemes d’assistència a la conducció (ADAS) és, avui dia, una de les àrees de recerca de més interès pel Centre de Visió per Computador. A partir de la informació adquirida per sensors instal·lats en un vehicle, els ADAS assisteixen al conductor per tal d’evitar situacions de perill. La validació d’aquests sistemes però, requereix de l’obtenció "manual" de les dades que defineixen l’entorn de conducció de forma precisa: una tasca costosa i subjecta a l’error humà. Per tal de resoldre aquest problema, en aquest projecte s’ha implementat IOCS, un simulador de conducció creat a partir d’un de robots, capaç de crear entorns realistes de conducció i d’obtenir, simultàniament, les dades sobre l’entorn inferides per un ADAS i les que el descriuen objectivament. Aquesta funcionalitat facilita extremadament el procés de validació actual dels sistemes d’assistència a la conducció.

Instrumentació i control d'actuadors fluídics per a sistemes analítics: sistema de regulació d'una microbomba de precisió a mode de xeringa

En aquest projecte s’ha implementat un sistema de control per a les bombes microfluídiques LPVX de The Lee Company funcionant a mode de xeringa. El sistema consisteix en un circuit controlador basat en el microxip UDN 296 B de Allegro MicroSystems, que conté dos Ponts en H per a controlar motors pas a pas i dos mòduls de Modulació d’Amplada de Polsos (PWM), governat a partir d’un programa de control com a instrument virtual dissenyat sota l’entorn LabVIEW. El programa de control permet indicar la quantitat de volum a aspirar o dispensar per la bomba i escollir entre una execució simple o una de continuada, podent-ne controlar en aquest segona opció el temps entre execució i execució. El programa també permet visualitzar el procés mitjançant la obtenció de la imatge d’una webcam amb DirectShow. Finalment també permet el control remot de l’Instrument Virtual a través de la xarxa d’Internet.

Is it redistribution or centralization? On the determinants of government investment in infrastructure

The dilemma efficiency versus equity, together with political partisan interests, has received increasing attention to explain the territorial allocation of investments. However, centralization intended to introduce or reinforce hierarchization in the political system has not been object as of now of empirical analysis. Our main contribution to the literature is providing evidence that meta-political objectives related to the ordering of political power and administration influence regional investment. In this way, we find evidence that network mode’s (roads and railways) investment programs are influenced by the centralization strategy of investing near to the political capital, while investment effort in no-network modes (airports and ports) appears to be positively related to distance. Since investment in surface transportation infrastructures is much higher than that in airports and ports, and taken into account that regions surrounding the political capital are poorer than the average, we suggest that centralization rather than redistribution has been the driver for the concentration of public investment on these regions.

Public and private learning from prices, strategic substitutability and complementarity, and equilibrium multiplicity

We study a general static noisy rational expectations model where investors have private information about asset payoffs, with common and private components, and about their own exposure to an aggregate risk factor, and derive conditions for existence and uniqueness (or multiplicity) of equilibria. We find that a main driver of the characterization of equilibria is whether the actions of investors are strategic substitutes or complements. This latter property in turn is driven by the strength of a private learning channel from prices, arising from the multidimensional sources of asymmetric information, in relation to the usual public learning channel. When the private learning channel is strong (weak) in relation to the public we have strong (weak) strategic complementarity in actions and potentially multiple (unique) equilibria. The results enable a precise characterization of whether information acquisition decisions are strategic substitutes or complements. We find that the strategic substitutability in information acquisition result obtained in Grossman and Stiglitz (1980) is robust. JEL Classification: D82, D83, G14 Keywords: Rational expectations equilibrium, asymmetric information, risk exposure, hedging, supply information, information acquisition.