bluuebunny/crossref_metadata_2025 huggingface dataset:
Las consecuencias económicas de la ocupación napoleónica en Lérida
Authors: Sánchez Carcelén Antoni
Published: February 2014

Este estudio histórico tiene como objetivo analizar las múltiples secuelas económicas derivadas de la conquista y posterior ocupación de Lérida por las tropas francesas. Básicamente, se han utilizado fuentes documentales conservadas en los distintos archivos de la ciudad de Lérida. El texto se ha dividido en epígrafes secundarios dedicados a la contribución de guerra napoleónica de 1810, los suministros en especie y en metálico a la Grande Armée, el abastecimiento de los hospitales militares, el control social mediante una férrea represión y las dificultades financieras derivadas de las cuantiosas imposiciones francesas. Atenuadas a partir de 1812 mediante el proyecto de recuperación económica del nuevo gobernador de Lérida, Alban de Villeneuve. Las pérdidas demográficas y materiales derivadas de la invasión, asalto y dominio napoleónico condicionó la restitución absolutista de Fernando VII y favoreció la proclamación en 1820 del sistema liberal, condicionado también por la herencia del pasado, que no era otra que la de una hacienda municipal arruinada.
Cunhal não foi Carrilo? Estratégia e Táctica do Partido Comunista Português durante a Crise Revolucionária de 1975
Authors: Cardeira Varela Raquel
Published: February 2014

[pt] Vários autores têm acentuado a divergência política entre a estratégia do Partido Comunista Português na Revolução dos Cravos em Portugal (1974-75) e a política ‘eurocomunista’ seguida pelo Partido Comunista de Espanha. Este artigo, realizado a partir de fontes primárias nacionais e internacionais, traça a história da política do PCP durante o «Verão Quente » de 1975. Focar-nos-emos na relação histórica do partido com os movimentos sociais, por um lado, e, por outro, na sua relação com o Governo. Finalmente, compara-se a política do PCP liderado por Álvaro Cunhal e a política do PCE dirigido por Santiago Carrillo, acentuando as semelhanças —defesa da coexistência pacífica, acordo com os partidos socialistas ibéricos, influência nos principais sindicatos— e as diferenças, que na nossa óptica se centram sobretudo na defesa de uma ordem capitalista fortemente regulada por parte do PCP, com a concretização de uma reforma agrária e um processo de nacionalizações de um sector importante da economia, por oposição à aceitação dos Pactos da Moncloa por parte do PCE, que assumem uma forma de economia de mercado de cunho mais liberal. Finalmente, a questão do regime (republicano ou monárquico) distingue também a política dos dois partidos.
Mathematical Modeling and Genetic Algorithms for Product Sequencing in a Cellular System
Authors: Süer Gürsel A. , Yarimoglu Fatih
Published: February 2014

This chapter considers a product-sequencing problem in a synchronized manufacturing environment, which is using a uniform time bucket approach for synchronization. This problem has been observed in a jewelry manufacturing company and is valid in other labor-intensive cellular environments. The scheduling problem handled has two aspects: first, determining manpower allocation; second, sequencing the products in order to minimize the number of periods where available manpower is exceeded. The number of operators needed in a time bucket may exceed the available manpower level as different products have different manpower requirements for different processes. A mathematical model is developed for the manpower allocation part of the problem. To perform product sequencing, two methods are used, namely mathematical modeling and genetic algorithm. A new five-phase GA approach is proposed, and the results show that it outperforms the classical GA. Several experiments have been conducted to find better GA parameters as well. Finally, GA results are compared with mathematical model results. Mathematical Modeling finds optimal result in a reasonable time for small problems. On the other hand, for the bigger problems, genetic algorithm is a feasible approach to use.
Modeling and Control of Production Task Flows using High-Level Activity-Based Petri Nets
Authors: Yasuda Gen’ichi
Published: February 2014

This chapter presents a systematic methodology for modeling and controlling productive tasks at the organization and coordination levels in advanced production systems, especially focusing on design and implementation aspects of lean production systems. Petri nets have been successfully introduced as an effective tool for describing control specifications and realizing the control. Nowadays, large-scale and complex production systems have a hierarchical structure, and the controllers are distributed according to their physical structure. Therefore, it is natural to realize the hierarchical and distributed management and control. In this chapter, to overcome some difficulties in the modeling of production systems with a large number of elements in Petri nets, High-Level Activity-Based Petri Nets (HAPN) are defined based on condition-event Petri nets. The high-level extended net representation of the production task flows can provide more synthetic specifications for consistent management and control of production systems by a top-down refinement methodology.
Implementing Lean in Engineer-to-Order Manufacturing
Authors: Matt Dominik T. , Rauch Erwin
Published: February 2014

This chapter reviews the state of the art in engineer-to-order production and non-repetitive production to give an overview of existing research and applications of Lean in this sector. Afterwards, a real case study at a medium-sized ETO manufacturer shows an approach to implement Lean Production in such a non-repetitive manufacturing environment. The experiences from the case study illustrate that the suitability of certain lean methods, such as value stream mapping or Kanban is limited, while other lean methods, such as 5S, CIP, or a material-oriented layout, brought significant changes. In the consolidation phase of the Lean production system, the authors defined a Lean-Toolset with the most suitable lean methods for engineer-to-order manufacturing systems. A core aspect of the Lean implementation was the desired mind-change of the employees. The chapter closes with a short description of the achieved results in the case study and gives an outlook to further research activities.
A Corporate Perspective on Global Management and Development of Lean Production Systems
Authors: Bellgran Monica
Published: February 2014

The challenge for every multinational manufacturing company with the ambition to implement the lean production concept is how to implement it worldwide within its global manufacturing footprint. There are many decisions that need to be taken from a company group perspective when planning and implementing a lean program. These concern the level of standardization on principles and tools, how to structure and organize additional resources, how to share experiences within the organization, and how to sustain the effort. These factors are elaborated in this chapter from a factory perspective based on the presentation of the lean journey of Gyproc AB, a process industry company within the Gypsum part of the large Saint Gobain group. The company has worked for about ten years with implementing world-class manufacturing and has extensive experience of the issues of starting-up and sustaining the lean-based concept.
Lean Management and Supply Chain Management
Authors: Martínez-Jurado Pedro J. , Moyano-Fuentes José
Published: February 2014

This chapter evaluates the state-of-the-art of research on Lean Management and Supply Chain Management strategies in the aerospace sector using Systematic Literature Review methodology. The complementary aims are: a) to identify the topic set studied and to propose a criterion for classifying the literature, and b) to discuss the empirical evidence that identifies existing interrelationships. The analysis has enabled three main topics to be identified: a) adoption and implementation of lean management, b) development of supply chain management, and c) deployment of lean principles and practices across the supply chain. A number of more specific lines of research are also proposed that have been assigned to each of these three main research topics. Finally, a set of challenges and opportunities for future research are set out, along with a range of academic and professional implications that could be useful not only for the aerospace sector but also for other industrial sectors that share similar contingent factors.
Dynamic Supply Chain Management for Lean Manufacturing
Authors: Tanimizu Yoshitaka
Published: February 2014

Lean is a management philosophy to eliminate waste both in the inside and from the outside of factories. A supply chain strategy is a key issue for the improvement of the outside. Recent information technologies provide even small- and medium-sized supplier companies with a chance for entering into contracts with major supplier companies and large manufacturing companies in different Keiretsu groups, but will give the trouble for surviving in the dynamic supply chain environment at the same time. This chapter proposes a strategy for MTO (Make To Order) companies to find suitable business partners in the dynamic supply chain environment and to enter into proper contracts with the partners as well as to obtain appropriate profits. A supply chain model proposed in the chapter provides a negotiation protocol to determine suitable prices and delivery times for ordered products through the iteration of the negotiation process between the organizations, as well as through the modification processes of production schedules. A two-layered supply chain model is firstly proposed as a basic model for dynamic supply chain management of MTO companies. The model is extended to a three-layered supply chain model for representing the negotiation protocol among multi-layered organizations. A prototype of a supply chain simulation system is developed and computational experiments are carried out to evaluate the effectiveness of changing business partners and negotiating among the partners cooperatively.
The Role of B2B E-Commerce in Market Share
Authors: Milgram-Baleix Juliette , Parravano Melanie , Pedauga Luis Enrique
Published: February 2014

This chapter explores the impact of the Internet and Business to Business (B2B) e-commerce on Spanish manufacturing firms’ market share while most studies focus on innovation and productivity. Using standard panel estimations, the authors find that firms with their own Web domain and that also carry out B2B e-commerce increase their market share, though this effect is not homogeneous among industries. B2B e-purchases have a more significant (and positive effect) on firms’ market share than B2B e-sales have. Unlike other studies, the authors also use a panel threshold regression specification that shows that e-commerce affects market share in a non-linear manner depending on firm’s characteristics. Larger firms and firms with higher share of skilled workers are better at increasing their market shares through Internet-based commerce strategies than other firms.
Internet as a Sales Channel for the Agri-Food Sector
Authors: Jurado Enrique Bernal , Moral Adoración Mozas , Viruel Miguel J. Medina
Published: February 2014

The Spanish market for organic products is notable for a supply side that offers one of the largest ranges in the world and a demand side that can only be termed symbolic. The reasons that have been given for this situation include the few and scattered points of sale, higher prices than for the conventional equivalents, and the consumers' disinformation about this product range. The Internet offers solutions to these barriers that some companies have used to facilitate online transactions in organic products. The case study presented in this chapter focuses on examining a virtual platform managed by an intermediary, not a producer, which puts producers and consumers of organic products in direct contact with each other. Making use of the Internet's advantages as a sales channel, developing a differentiation strategy based on promoting values such as the environment and sustainability, and the company's mutualist relationship with its small-scale suppliers have generated an associate and customer base that ensures the success of this business model.
How to Develop WOM Marketing
Authors: López Manuela , Sicilia María
Published: February 2014

Word of Mouth (WOM) is the most influential and credible information source for consumers. The development of the Internet has enabled consumers to share information easier and easier. Information can be watched by consumers around the world. Companies are increasingly interested in using WOM as a new marketing tool. They are encouraging consumers to spread the word about their products. This intentional influencing of consumer-to-consumer communications via professional marketing techniques is called WOM Marketing (WOMM). Companies are currently in the process of learning how to develop WOMM campaigns. In addition, although more and more studies are analyzing WOMM, the topic is still very recent. Thus, the aim of this chapter is twofold. First, it tries to provide a clearer picture of and existing doubts regarding conceptualization of this new communication tool. Second, the chapter compiles and presents the main gaps found in the literature that future research should investigate for establishing guidelines that could be useful for companies when developing WOMM activities.
New Market Segmentation Paradigms and Electronic Commerce Adoption
Authors: Agudo-Peregrina Ángel F. , Chaparro-Peláez Julián , Hernández-García Ángel
Published: February 2014

The purpose of this chapter is to offer a better understanding of online shoppers’ behaviour, so that virtual shops may improve and adapt their product offering to effectively reach their target segments. In order to achieve this goal, a characterization of motivations to shop online is proposed as a basis for motivation-based customer segmentation. Building upon this segmentation, acceptance models—namely, an adaptation of UTAUT2 to e-commerce—have been used to look further into the purchasing behavior of each identified segment. The results from the empirical study based on responses to an online questionnaire from a sample of 718 Spanish shoppers shows seven different groups of motivations and five different customer segments, and confirms different behavioral patterns in the adoption of e-commerce for different segments of customers, with special influence of effort expectancy, facilitating conditions, and perceived risk in the online shopping behaviour of individuals.
How Can E-Vendors Create Trust in B2C and C2C Contexts?
Authors: San-Martín Sonia , Camarero Carmen
Published: February 2014

One of the most important and the most difficult challenges in the context of an online as opposed to an offline purchase is how to generate consumer trust. It is likely that the signals that generate trust will differ in online C2C auctions from online B2C purchasing through other Websites. This chapter follows signaling theory and presents a model that attempts to capture the effects of Website signals and perceived risk on consumer trust and draws comparisons between C2C and B2C online contexts using multigroup analysis. Using information collected from a sample of online buyers, results show that vendors should stress the quality of information given to the client on C2C Websites, the offer of a wide variety of competitive prices, and the guarantee of meeting deadlines, whereas in the case of B2C sites there seem to be a series of factors that create trust in a balanced way.
Perceived Risk in E-Commerce and the Development of Loyalty
Authors: Alcántara-Pilar Juan Miguel , del Barrio-García Salvador
Published: February 2014

This chapter examines the effect of Website design, the language used on the Website, and the user’s flow state while browsing on processing online information in terms of perceived security and loyalty towards the tourism service being promoted. The results underline the importance of Website design and language on perceived risk online, and of user flow state on the development of loyalty towards the tourist destination in question. It was found that user involvement with the site content is a key moderator in reducing perceived risk and increasing loyalty. In light of the findings, firms are recommended to select content for their Websites that reflect the different types of client motivation so as to make browsing more useful and appealing to users.
Drop-Out Risk Measurement of E-Banking Customers
Authors: Lara-Rubio Juan , Martínez-Fiestas Myriam , Cortés-Romero Antonio M.
Published: February 2014

During the last decade, the national financial markets have shown a great transformation that has failed to reduce the high rate of existing banking in spite of the current financial crisis. This high level of competition makes financial institutions concerned about the loyalty of their customers to maintain or increase their market share and profitability. In this chapter, the authors propose a statistical model that measures the risk of customers dropping out of a Spanish financial institution, and this is a widespread method for the financial sector in general. The risk depends on socio-demographic and economic factors, as well as—most importantly—on the levels of satisfaction and trust that the bank produces in customers. Research shows that the proposed model can help institutions to know which customers have a greater risk of dropping out and, therefore, establish some recommendations for their loyalty.
Overview of Mobile Payment
Authors: Raina Vibha Kaw
Published: February 2014

According to the Mobile Payment Forum, mobile payments are the transactions with a monetary value that is conducted through a mobile telecommunications network through diverse mobile users devices, such as cellular telephones, smart phones or PDAs, and mobile terminals. Mobile payment is a transfer of funds in return for goods or services in which a mobile device is functionally involved in executing and confirming payment. The payer can be standing at a POS or be interacting with a merchant located somewhere else. Mobile payment systems enable customers to purchase and pay for goods or services via mobile phones. Here, each mobile phone is used as the personal payment tool in connection with the remote sales. Payments can take place far away from both the recipient and the bank. This chapter gives an overview of mobile payments.
New Perspectives on Payment Systems
Authors: Ramos de Luna Iviane , Montoro-Ríos Francisco , Liébana-Cabanillas Francisco J.
Published: February 2014

The technological developments in the mobile industry during the last few years have led companies to increase the functionalities of mobile phones. According to many authors in the field, the NFC mobile payment has become one of the payment systems of the future thanks to its numerous advantages. This chapter revises the importance of this payment system within the mobile commerce strategy that many companies are adopting. The model used in the research is based on the classic variables of the technological acceptance model, together with other variables from recent studies. The results obtained in this research show the decisive impact of perceived compatibility, attitude, and subjective norms on the future intention to use this system. Finally, the authors underline the main implications for management, as well as some strategies that strengthen this new business in the context of the new technical developments.
Emerging Technologies for User-Friendly Mobile Payment Applications
Authors: Raina Vibha Kaw
Published: February 2014

The advancement and the evolution of mobile communications and mobile device technology have led to a remarkable growth and tremendous requirement for mobile applications that are carried on mobile phones. These technologies have lead to the deployment of business, communications, and mobile services, and hence, gave rise to mobile payments. The mobile payments are considered as the killer applications and are real-time cashless payments. Mobile payments take place with the help of mobile telephony and communications where maintaining security solutions becomes an important factor. This chapter describes the different emerging technologies carried out between a resource-limited mobile device and a resource-rich computer server over wireless networks.
The role of low volatile organics on secondary organic aerosol formation
Authors: Kokkola H. , Yli-Pirilä P. , Vesterinen M. , Korhonen H. , Keskinen H. , Romakkaniemi S. , Hao L. , Kortelainen A. , Joutsensaari J. , Worsnop D. R. , Virtanen A. , Lehtinen K. E. J.
Published: February 2014

Abstract. Large-scale atmospheric models, which typically describe secondary organic aerosol (SOA) formation based on chamber experiments, tend to systematically underestimate observed organic aerosol burdens. Since SOA constitutes a significant fraction of atmospheric aerosol, this discrepancy translates into an underestimation of SOA contribution to radiative forcing of atmospheric aerosol. Here we show that the underestimation of SOA yields can be partly explained by wall losses of SOA forming compounds during chamber experiments. We present a chamber experiment where α-pinene and ozone are injected into a Teflon chamber. When these two compounds react, we observe rapid formation and growth of new particles. Theoretical analysis of this formation and growth event indicates rapid formation of oxidized volatile organic compounds (OVOC) of very low volatility in the chamber. If these oxidized organic compounds form in the gas phase, their wall losses will have significant implications on their partitioning between the gas and particle phase. Although these OVOCs of very low volatility contribute to the growth of new particles, their mass will almost completely be depleted to the chamber walls during the experiment, while the depletion of OVOCs of higher volatilities is less efficient. According to our model simulations, the volatilities of OVOC contributing to the new particle formation event can be of the order of 10−5 μg m−3.
Spatially resolving methane emissions in California: constraints from the CalNex aircraft campaign and from present (GOSAT, TES) and future (TROPOMI, geostationary) satellite observations
Authors: Wecht K. J. , Jacob D. J. , Sulprizio M. P. , Santoni G. W. , Wofsy S. C. , Parker R. , Bösch H. , Worden J.
Published: February 2014

Abstract. We apply a continental-scale inverse modeling system for North America based on the GEOS-Chem model to optimize California methane emissions at 1/2° × 2/3° horizontal resolution using atmospheric observations from the CalNex aircraft campaign (May–June 2010) and from satellites. Inversion of the CalNex data yields a best estimate for total California methane emissions of 2.86 ± 0.21 Tg yr−1, compared with 1.92 Tg yr−1 in the EDGAR v4.2 emission inventory used as a priori and 1.51 Tg yr−1 in the California Air Resources Board (CARB) inventory used for state regulations of greenhouse gas emissions. These results are consistent with a previous Lagrangian inversion of the CalNex data. Our inversion provides 12 independent pieces of information to constrain the geographical distribution of emissions within California. Attribution to individual source types indicates dominant contributions to emissions from landfills/wastewater (1.1 Tg yr−1), livestock (0.87 Tg yr−1), and gas/oil (0.64 Tg yr−1). EDGAR v4.2 underestimates emissions from livestock while CARB underestimates emissions from landfills/wastewater and gas/oil. Current satellite observations from GOSAT can constrain methane emissions in the Los Angeles Basin but are too sparse to constrain emissions quantitatively elsewhere in California (they can still be qualitatively useful to diagnose inventory biases). Los Angeles Basin emissions derived from CalNex and GOSAT inversions are 0.42 ± 0.08 and 0.31 ± 0.08, respectively. An observation system simulation experiment (OSSE) shows that the future TROPOMI satellite instrument (2015 launch) will be able to constrain California methane emissions at a detail comparable to the CalNex aircraft campaign. Geostationary satellite observations offer even greater potential for constraining methane emissions in the future.
Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) scientific objectives
Authors: Riese M. , Oelhaf H. , Preusse P. , Blank J. , Ern M. , Friedl-Vallon F. , Fischer H. , Guggenmoser T. , Höpfner M. , Hoor P. , Kaufmann M. , Orphal J. , Plöger F. , Spang R. , Suminska-Ebersoldt O. , Ungermann J. , Vogel B. , Woiwode W.
Published: February 2014

Abstract. The upper troposphere/lower stratosphere (UTLS) plays a crucial role in the climate system. Changes in the composition and dynamic structure of this atmospheric region result in particularly large changes in the atmospheric radiation balance. Quantifying the physical and chemical processes that control UTLS composition therefore represents an important task. Currently, there is a lack of UTLS observations with sufficient three-dimensional resolution. The Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) aircraft instrument addresses this observational lack by providing observations of numerous trace constituents as well as temperature and cloud structures with an unprecedented combination of vertical resolution (up to 300 m) and horizontal resolution (up to 20 km × 20 km). As a result, important scientific questions concerning stratosphere–troposphere-exchange, the occurrence of subvisible cirrus clouds in the lowermost stratosphere (LMS), polar chemistry and gravity wave processes can be addressed, as reviewed in this paper.
Spatio-temporal patterns of C : N : P ratios in the northern Benguela upwelling system
Authors: Flohr A. , van der Plas A. K. , Emeis K.-C. , Mohrholz V. , Rixen T.
Published: February 2014

Abstract. On a global scale the ratio of fixed nitrogen (N) and phosphate (P) is characterized by a deficit of N with regard to the classical Redfield ratio of N : P = 16 : 1 reflecting the impact of N loss occurring in the oceanic oxygen minimum zones. The northern Benguela upwelling system (NBUS) is known for losses of N and the accumulation of P in sub- and anoxic bottom waters and sediments of the Namibian shelf resulting in low N : P ratios in the water column. To study the impact of the N : P anomalies on the regional carbon cycle and their consequences for the export of nutrients from the NBUS into the oligotrophic subtropical gyre of the South Atlantic, we measured dissolved inorganic carbon (CT), total alkalinity (AT), oxygen (O2) and nutrient concentrations in February 2011. The results indicate increased P concentrations over the Namibian shelf due to P efflux from sediments resulting in a C : N : P : -O2 ratio of 106 : 16 : 1.6 : 138. N reduction further increase C : N and reduce N : P ratios in those regions where O2 concentrations in bottom waters are < 20 μmol kg−1. However, off the shelf along the continental margin, the mean C : N : P : -O2 ratio is again close to the Redfield stoichiometry. Additional nutrient data measured during two cruises in 2008 and 2009 imply that the amount of excess P, which is created in the bottom waters on the shelf, and its export into the subtropical gyre after upwelling varies through time. The results further reveal an inter-annual variability of excess N within the South Atlantic Central Water (SACW) that flows from the north into the NBUS, with highest N values observed in 2008. It is postulated that the N excess in SACW occurred due to the impact of remineralized organic matter produced by N2 fixation and that the magnitude of excess P formation and its export is governed by inputs of excess N along with SACW flowing into the NBUS. Factors controlling N2 fixation north of the BUS need to be addressed in future studies to better understand the role of the NBUS as a P source and N sink in the coupled C : N : P cycles.
Rapid and sudden advection of warm and dry air in the Mediterranean Basin
Authors: Mazon J. , Pino D. , Barriendos M.
Published: February 2014

Abstract. Rapid advection of extremely warm and dry air is studied during two events in the Mediterranean Basin. On 27 August 2010 a rapid advection of extremely warm and dry air affected the northeast Iberian Peninsula during a few hours. At the Barcelona city center, the temperature reached 39.3 ° C, which is the maximum temperature value recorded during 230 yr of daily data series. On 23 March 2008 a rapid increase of temperature and drop of relative humidity were recorded for a few hours in Heraklion (Crete). During the morning on that day, the recorded temperature reached 34 °C for several hours on the northern coastline of this island. According to the World Meteorological Organization none of these events can be classified as a heat wave, which requires at least two days of abnormally high temperatures; neither are they a heat burst as defined by the American Meteorological Society, where abnormal temperatures take place during a few minutes. For this reason, we suggest naming this type of event flash heat. By using data from automatic weather stations in the Barcelona and Heraklion area and WRF mesoscale numerical simulations, these events are analyzed. Additionally, the primary risks and possible impacts on several fields are presented.
Modeling of fast ground subsidence observed in southern Saskatchewan (Canada) during 2008–2011
Authors: Samsonov S. V. , González P. J. , Tiampo K. F. , d'Oreye N.
Published: February 2014

Abstract. Fast ground subsidence in southern Saskatchewan (Canada) between the city of Saskatoon and Rice Lake was observed with the RADARSAT-2 interferometric synthetic aperture radar (InSAR) during 2008–2011. We collected 23 ascending Multi-Look Fine 3 Far (MF3F) and 15 descending Standard 3 (S3) RADARSAT-2 images and performed time-series analysis utilizing Small Baseline Subset (SBAS) and Multidimensional SBAS (MSBAS) methodologies. We observed two well-defined circular regions located a few kilometers apart and subsiding with the nearly constant rate of about 10 cm yr-1. MSBAS decomposition revealed the presence of both vertical and horizontal ground displacements. For further analysis we selected two highly coherent interferograms spanning from November to December 2009 until April 2010 thanks to particularly favorable ground conditions that displayed superior coherence. We performed modeling and inversion assuming spherical and sill source models in order to determine the source location, depth and strength. The sill source model produced the smallest residual of 0.7 cm yr-1 applied to ascending interferograms and 0.9 cm yr-1 applied to descending interferograms. A residual of 1.0 cm yr-1 was achieved with the sill model when both ascending and descending interferograms were used. This model suggested sources located at 1.3 and 1.2 km depth with radius of 1.0 and 1.3 km for eastern and western areas, respectively. The spherical model suggested slightly shallower sources located at 0.9 and 0.8 km. We could not precisely identify the cause of this deformation, but the observed subsidence rate and source depth suggest mining-related origin. Topographic changes produced by this subsidence rate over a long time may produce shallow groundwater redistribution and flooding of agricultural lands.
Seismic and mechanical studies of the artificially triggered rockfall at the Mount Néron (French Alps, December 2011)
Authors: Bottelin P. , Jongmans D. , Daudon D. , Mathy A. , Helmstetter A. , Bonilla-Sierra V. , Cadet H. , Amitrano D. , Richefeu V. , Lorier L. , Baillet L. , Villard P. , Donzé F.
Published: February 2014

Abstract. The eastern limestone cliff of Mount Néron (French Alps) was the theatre of two medium-size rockfalls between summer and winter 2011. On 14 August 2011, a ~ 2000 m3 rock compartment detached from the cliff, fell 100 m below and propagated down the slope. Although most of the fallen rocks deposited in the upper part of the slope, about 15 meter-size blocks were stopped by a ditch and an earthen barrier after a runout of 800 m. An unstable overhanging ~ 2600 m3 compartment remained attached to the cliff and was blasted on 13 December 2011. During this artificially triggered event, 7 blocks reached the same ditch, with volumes ranging from 0.8 to 12 m3. A semi-permanent seismic array located about 2.5 km from the site recorded the two events, providing a unique opportunity to understand and to compare the seismic phases generated during natural and artificially triggered rockfalls. Both events have signal duration of ~ 100 s with comparable maximum amplitudes recorded at large distances (computed local magnitude of 1.14 and 1.05, respectively), most of the energy lying below 20 Hz. Remote sensing techniques (photogrammetry and LiDAR) were employed before and after the provoked rockfall, allowing the volume and fracturing to be characterized. This event was filmed by two video cameras and the generated ground motions were recorded using two temporary 3C seismic sensors and 3 seismic arrays deployed at the slope toe. Movie and seismogram processing provided estimates of the propagation velocity during the successive rockfall phases, which ranges from 12 m s−1 to 30 m s−1. The main seismic phases were obtained from combined video and seismic signal analyses. The two most energetic phases are related to the ground impact of fallen material after free-fall, and to individual rock block impacts into the ditch and the earthen barrier. These two phases are characterized by similar low-frequency content but show very different particle motions. The discrete element technique allowed reproducing the key features of the rockfall dynamics, yielding propagation velocities compatible with experimental observations.
Large-amplitude electromagnetic waves in magnetized relativistic plasmas with temperature
Authors: Muñoz V. , Asenjo F. A. , Domínguez M. , López R. A. , Valdivia J. A. , Viñas A. , Hada T.
Published: February 2014

Abstract. Propagation of large-amplitude waves in plasmas is subject to several sources of nonlinearity due to relativistic effects, either when particle quiver velocities in the wave field are large, or when thermal velocities are large due to relativistic temperatures. Wave propagation in these conditions has been studied for decades, due to its interest in several contexts such as pulsar emission models, laser-plasma interaction, and extragalactic jets. For large-amplitude circularly polarized waves propagating along a constant magnetic field, an exact solution of the fluid equations can be found for relativistic temperatures. Relativistic thermal effects produce: (a) a decrease in the effective plasma frequency (thus, waves in the electromagnetic branch can propagate for lower frequencies than in the cold case); and (b) a decrease in the upper frequency cutoff for the Alfvén branch (thus, Alfvén waves are confined to a frequency range that is narrower than in the cold case). It is also found that the Alfvén speed decreases with temperature, being zero for infinite temperature. We have also studied the same system, but based on the relativistic Vlasov equation, to include thermal effects along the direction of propagation. It turns out that kinetic and fluid results are qualitatively consistent, with several quantitative differences. Regarding the electromagnetic branch, the effective plasma frequency is always larger in the kinetic model. Thus, kinetic effects reduce the transparency of the plasma. As to the Alfvén branch, there is a critical, nonzero value of the temperature at which the Alfvén speed is zero. For temperatures above this critical value, the Alfvén branch is suppressed; however, if the background magnetic field increases, then Alfvén waves can propagate for larger temperatures. There are at least two ways in which the above results can be improved. First, nonlinear decays of the electromagnetic wave have been neglected; second, the kinetic treatment considers thermal effects only along the direction of propagation. We have approached the first subject by studying the parametric decays of the exact wave solution found in the context of fluid theory. The dispersion relation of the decays has been solved, showing several resonant and nonresonant instabilities whose dependence on the wave amplitude and plasma temperature has been studied systematically. Regarding the second subject, we are currently performing numerical 1-D particle in cell simulations, a work that is still in progress, although preliminary results are consistent with the analytical ones.
Sea-ice extent and its trend provide limited metrics of model performance
Authors: Notz D.
Published: February 2014

Abstract. We examine how the evaluation of modelled sea-ice coverage against reality is affected by uncertainties in the retrieval of sea-ice coverage from satellite, by the usage of sea-ice extent to overcome these uncertainties, and by internal variability. We find that for Arctic summer sea ice, model biases in sea-ice extent can be qualitatively different from biases in sea-ice area. This is because about half of the CMIP5 models and satellite retrievals based on the Bootstrap and the ASI algorithm show a compact ice cover in summer with large areas of high-concentration sea ice, while the other half of the CMIP5 models and satellite retrievals based on the NASA Team algorithm show a loose ice cover. For the Arctic winter sea-ice cover, differences in grid geometry can cause synthetic biases in sea-ice extent that are larger than the observational uncertainty. Comparing the uncertainty arising directly from the satellite retrievals with those that arise from internal variability, we find that the latter by far dominates the uncertainty estimate for trends in sea-ice extent and area: most of the differences between modelled and observed trends can simply be explained by internal variability. For absolute sea-ice area and sea-ice extent, however, internal variability cannot explain the difference between model and observations for about half the CMIP5 models that we analyse here. All models that we examined have regional biases, as expressed by the root-mean-square error in concentration, that are larger than the differences between individual satellite algorithms.
Optical Spectroscopy and Crystal Field Studies of the Mn4+ Ion (3d3) in the Double Perovskite NaLaMgTeO6
Authors: Srivastava Alok M. , Brik Mikhail G. , Camardello Samuel J. , Comanzo Holly A. , Garcia-Santamaria Florencio
Published: February 2014

The spectroscopic properties of the Mn4+ ion (3d3) in the double perovskite NaLaMgTeO6 are reported in this work. Evidence is presented for the occupation by the Mn4+ ion of both the six coordinated Mg2+ and Te6+ sites in the host structure. The Mn4+ energy levels are calculated using the exchange charge model of crystal field theory for both occupied sites. The results of our calculations yield the crystal field splitting and Racah parameters of Dq = 2008 cm−1, B = 790 cm−1, C =2881 cm−1, with C/B=3:65 (Mg2+ site) and Dq=2008 cm−1, B=790 cm−1,C =2949 cm−1, with C/B = 3:73 (Te6+ site). A cross-cutting comparative study of the variations in the crystal field splitting and the Racah parameters of the six-coordinated Mn4+ ion in a series of materials with the perovskite structure are presented.
Synchrotron Radiation Study of Interconfigurational 5d-4f Luminescence of Pr3+ in KLuP2O7
Authors: Trevisani Mattia , Ivanovskikh Konstantin , Piccinelli Fabio , Bettinelli Marco
Published: February 2014

The double phosphate KLuP2O7 doped with Pr3+ ions was prepared by solid-state reaction. The material obtained was characterized by powder X-ray diffraction. The luminescence spectroscopy and the excited state dynamics of this material were studied upon excitation with VUV synchrotron radiation. The 5d-4 f emission of Pr3+ upon both direct and band gap excitation was detected and assigned. The decay kinetics of the Pr3+ 5d-4 f emission is characterized by a decay time of about 20 ns and is nearly temperature independent within the range 8 - 300 K. Both dynamics and energy transfer peculiarities revealed in the study suggested good potentials for application of KLuP2O7:Pr3+ as a fast scintillator material.
Preparation and Characterization of Transparent, Photoluminescent MgAl2O4:Eu2+ Ceramics
Authors: Waetzig Katja , Kinski Isabel
Published: February 2014

The influence of 0.1 mol-% Eu2+ doping in a transparent MgAl2O4 ceramic on the optical properties has been investigated. The goal was to prepare first an Eu3+-doped spinel by a conventional sintering process for a transparent ceramic followed by a reductive densification step yielding an Eu2+-doped product. Commercially available spinel powder was doped with 0.1 mol-% europium using a nitrate salt and afterwards compacted into green bodies. In the following process the specimens were pre-sintered and post-densified using hot isostatic pressing (HIP) in an argon atmosphere. The transparency of the disks was measured optically using UV/Vis and fluorescence spectroscopy. After optimization of the sintering conditions the resulting Eu2+-doped spinel showed a transparency of 77:4% and a conversion of the UV light with a wavelength of 260 nm into blue light with a wavelength of 450 nm.
Efficient Red Emission from Europium Chelate-Silicone Host-Guest Hybrids
Authors: Tran Thanh H. , Bentlage Michael , Lezhnina Marina M. , Kynast Ulrich
Published: February 2014

Due to their ease of fabrication, chemical stability and optical transparency polydimethylsiloxanederived silicones ([O-Si(CH3)2]∞) are excellent matrices to enable optical functions. We here report on the luminescence of silicone hybrids with red-emitting europium diketonate complexes, which have not been described previously in this matrix. The problem of too low solubility of the pure complexes has been resolved by co-coordination with trioctylphosphine oxide (TOPO), which permits complex concentrations of up to 5×10−3 mol L−1, at the same time maintaining complete transparency. Quantum efficiencies in excess of 60% could thus be obtained for benzoyltrifluoroacetonates, and near 50% for thenoyltrifluoroacetonates. These high efficiencies have been confirmed by room-temperature life time measurements, which displayed straight single-exponential decay behavior for both complexes independent of their concentration in the silicone.
Fluorescence-active Waveguides by the Sol-Gel Method. Theory and Application
Authors: Reisfeld Renata
Published: February 2014

Active waveguides can be applied in environmental sensors, telecommunication, medicine, computers and electronic convertors. The sol-gel technology allows formation of planar and fiber waveguides incorporating fluorescent organic and inorganic dopands. Several sol-gel matrices which enable the incorporation of lanthanides and their complexes and fluorescent organic molecules are presented. A short description of the theory of luminescence of lanthanides is outlined and examples of active waveguides known today are given. The mechanisms for infrared to visible light conversion are explained. Suggestions for practical approach to novel active waveguides are given. Increase of fluorescence as a result of an interaction of fluorescent species with metal nanoparticles is presented.
A Simulation Environment for Bio-inspired Heterogeneous Chained Modular Robots
Authors: Brunete Alberto , Hernando Miguel , Gambao Ernesto
Published: February 2014

This paper presents a new simulation environment aimed at heterogeneous chained modular robots. This simulator allows for the testing of the feasibility of the design, the checking of how the modules will perform in the field, and the verifying of the hardware, electronics and communication designs before the prototype is built, saving time and resources. The paper shows how the simulator is built and how it can be set up to adapt to new designs. It also gives some examples of its use showing different heterogeneous modular robots running in different environments.
A Novel Robust Scene Change Detection Algorithm for Autonomous Robots Using Mixtures of Gaussians
Authors: Manso Luis J. , Núñez Pedro , Silva Sidnei da , Drews-Jr Paulo
Published: February 2014

Interest in change detection techniques has considerably increased during recent years in the field of autonomous robotics. This is partly because changes in a robot's working environment are useful for several robotic skills (e.g., spatial cognition, modelling or navigation) and applications (e.g., surveillance or guidance robots). Changes are usually detected by comparing current data provided by the robot's sensors with a previously known map or model of the environment. When the data consists of a large point cloud, dealing with it is a computationally expensive task, mainly due to the amount of points and the redundancy. Using Gaussian Mixture Models (GMM) instead of raw point clouds leads to a more compact feature space that can be used to efficiently process the input data. This allows us to successfully segment the set of 3D points acquired by the sensor and reduce the computational load of the change detection algorithm. However, the segmentation of the environment as a Mixture of Gaussians has some problems that need to be properly addressed. In this paper, a novel change detection algorithm is described in order to improve the robustness and computational cost of previous approaches. The proposal is based on the classic Expectation Maximization (EM) algorithm, for which different selection criteria are evaluated. As demonstrated in the experimental results section, the proposed change detection algorithm achieves the detection of changes in the robot's working environment faster and more accurately than similar approaches.
Online Joint Trajectory Generation of Human-like Biped Walking
Authors: Kim Jong-Wook
Published: February 2014

Biped walking has long been studied in the area of gait analysis and robotic locomotion. The goal of this paper is to establish a systematic methodology for human-like natural walking by fusing the measured human joint data and optimal pattern generation techniques based on a full-body humanoid model. To this end, this paper proposes an adaptive two-stage gait pattern by which the step length and walking velocity can be changed with two scaling factors. In addition, to cope with the situations involving passing over a small obstacle, the joint trajectories of the swing foot can be adjusted with a novel concept of differential angle trajectory using a reliable optimization method, viz. particle swarm optimization. The feasibility of the proposed walking scheme is validated by walking experiments with the robot platform DARwIn-OP.
An Infant Development-inspired Approach to Robot Hand-eye Coordination
Authors: Chao Fei , Lee Mark H. , Jiang Min , Zhou Changle
Published: February 2014

This paper presents a novel developmental learning approach for hand-eye coordination in an autonomous robotic system. Robotic hand-eye coordination plays an important role in dealing with real-time environments. Under the approach, infant developmental patterns are introduced to build our robot's learning system. The method works by first constructing a brain-like computational structure to control the robot, and then by using infant behavioural patterns to build a hand-eye coordination learning algorithm. This work is supported by an experimental evaluation, which shows that the control system is implemented simply, and that the learning approach provides fast and incremental learning of behavioural competence.