bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancing Students’ Engagement
Authors: Turner Julianne C. , Christensen Andrea , Kackar-Cam Hayal Z. , Trucano Meg , Fulmer Sara M.
Published: April 2014

All teachers ( N = 32) at one middle school participated in a university-led intervention to improve student engagement. Teachers discussed four principles of motivation and related instructional strategies. Teachers enacted instructional strategies in their classrooms. We observed six randomly selected teachers and their students over 3 years. Analyses of the dynamic patterns of teacher-student interaction (using an application of state space grids) revealed two distinct patterns. The upward group ( n = 3) showed an increase of teacher motivational support and student engagement. The stable group ( n = 3) demonstrated low levels of both teacher motivational support and student engagement. Qualitative analyses of instructional differences between the two groups help explain student engagement. Implications include conceptualizing student engagement as interpersonal classroom activity and measuring change as developmental and dynamic phenomena.
Heat Treatment Effects of Laser Cladded 12 Ni Maraging Tool Steel with Ni-Co-Mo Alloys*
Authors: Bergant Zoran , Grum Janez
Published: April 2014

The aim of the research is to study the effect of a two-stage heat treatment process of two iron based Ni-Co-Mo alloys on microstructure, micro-hardness and residual stress distribution. The laser cladding with multi-jet powder injection was used to deposit different alloys on the 12 % nickel maraging tool steel specimens 1.2799 (SIST EN 10027-2) to study the effect on the material's properties. In Ni-Co-Mo-1 austenite alloy, the precipitation hardening had no effect on hardness even after a prolonged overaging for 16 hours at 720 C. The second alloy Ni-Co-Mo-2 has a chemical composition similar to the maraging steel substrate. After 3 hours of precipitation hardening at 550 C, the alloy hardness increased to the level of base material. The residual stresses were measured using the hole drilling method. The residual stress profiles into the depth show predominantly tensile residual stresses in the Ni-Co-Mo-1 deposit and compressive residual stresses in the Ni-Co-Mo-2 deposit. The results indicate the importance of the chemical composition on microstructure, hardness and residual stresses prior and after heat treatment as well as of the quality of the deposited material on the maraging steel.
Does curricular change improve faculty perceptions of student experiences with the educational environment? A preliminary study in an institution undergoing curricular change
Authors: Shehnaz Syed Ilyas , Sreedharan Jayadevan , Gomathi Kadayam Guruswami
Published: April 2014

Purpose: College of Medicine, Gulf Medical University, United Arab Emirates, underwent a major curriculum change from a discipline-based to an organ system-based integrated curriculum. However, it was not known how the faculty perceived the changes in the educational environment as experienced by the students. In this context, we aimed to compare the faculty perceptions of the student experiences in the discipline-based curriculum with those in the organ system-based integrated curriculum.Methods: The Dundee Ready Education Environment Measure (DREEM) questionnaire was modified to assess faculty perceptions of the student experiences, pilot-tested, and administered to all faculty members (n=28) involved in the discipline-based curriculum (FDC) in January 2009. In the subsequent year, data were collected from the same faculty involved in the new integrated curriculum (FIC). Collected data were transferred to Predictive Analytics Software version 18. Total, domain, and individual statement scores were assessed with the Wilcoxon signed rank test. Percentage agreement, disagreement, and uncertainty were assessed by the McNemar’s test for proportion.Results: The mean total DREEM score was significantly higher (P<0.001) for FIC (139/200) as compared to FDC (119/200). The FIC perceived significantly more positive student experiences with the educational environment as indicated by the domain scores and statement scores. The differences in proportions of agreement between FIC and FDC also reinforced that the FIC perceived more positive student experiences with the educational environment.Conclusion: The study showed that the faculty perceived the organ system-based integrated curriculum as providing a better educational environment for the students than the discipline based curriculum.
Crop Dominance Mapping with IRS-P6 and MODIS 250-m Time Series Data
Authors: Gumma Murali , Pyla Kesava , Thenkabail Prasad , Reddi Venkataramana , Naresh Gundapaka , Mohammed Irshad , Rafi Ismail
Published: April 2014

This paper describes an approach to accurately separate out and quantify crop dominance areas in the major command area in the Krishna River Basin. Classification was performed using IRS-P6 (Indian Remote Sensing Satellite, series P6) and MODIS eight-day time series remote sensing images with a spatial resolution of 23.6 m, 250 m for the year 2005. Temporal variations in the NDVI (Normalized Difference Vegetation Index) pattern obtained in crop dominance classes enables a demarcation between long duration crops and short duration crops. The NDVI pattern was found to be more consistent in long duration crops than in short duration crops due to the continuity of the water supply. Surface water availability, on the other hand, was dependent on canal water release, which affected the time of crop sowing and growth stages, which was, in turn, reflected in the NDVI pattern. The identified crop-wise classes were tested and verified using ground-truth data and state-level census data. The accuracy assessment was performed based on ground-truth data through the error matrix method, with accuracies from 67% to 100% for individual crop dominance classes, with an overall accuracy of 79% for all classes. The derived major crop land areas were highly correlated with the sub-national statistics with R2 values of 87% at the mandal (sub-district) level for 2005–2006. These results suggest that the methods, approaches, algorithms and datasets used in this study are ideal for rapid, accurate and large-scale mapping of paddy rice, as well as for generating their statistics over large areas. This study demonstrates that IRS-P6 23.6-m one-time data fusion with MODIS 250-m time series data is very useful for identifying crop type, the source of irrigation water and, in the case of surface water irrigation, the way in which it is applied. The results from this study have assisted in improving surface water and groundwater irrigated areas of the command area and also provide the basis for better water resource assessments at the basin scale.
Enabling Privacy in Vehicle-to-Grid Interactions for Battery Recharging
Authors: Rottondi Cristina , Fontana Simone , Verticale Giacomo
Published: April 2014

The diffusion of Electric Vehicles (EV) fostered by the evolution of the power system towards the new concept of Smart Grid introduces several technological challenges related to the synergy among electricity-propelled vehicle fleets and the energy grid ecosystem. EVs promise to reduce carbon emissions by exploiting Renewable Energy Sources (RESes) for battery recharge, and could potentially serve as storage bank to flatten the fluctuations of power generation caused by the intermittent nature of RESes by relying on a load aggregator, which intelligently schedules the battery charge/discharge of a fleet of vehicles according to the users’ requests and grid’s needs. However, the introduction of such vehicle-to-grid (V2G) infrastructure rises also privacy concerns: plugging the vehicles in the recharging infrastructures may expose private information regarding the user’s locations and travelling habits. Therefore, this paper proposes a privacy-preserving V2G infrastructure which does not disclose to the aggregator the current battery charge level, the amount of refilled energy, nor the time periods in which the vehicles are actually plugged in. The communication protocol relies on the Shamir Secret Sharing threshold cryptosystem. We evaluate the security properties of our solution and compare its performance to the optimal scheduling achievable by means of an Integer Linear Program (ILP) aimed at maximizing the ratio of the amount of charged/discharged energy to/from the EV’s batteries to the grid power availability/request. This way, we quantify the reduction in the effectiveness of the scheduling strategy due to the preservation of data privacy.
Climate Services to Improve Public Health
Authors: Jancloes Michel , Thomson Madeleine , Costa María , Hewitt Chris , Corvalan Carlos , Dinku Tufa , Lowe Rachel , Hayden Mary
Published: April 2014

A high level expert panel discussed how climate and health services could best collaborate to improve public health. This was on the agenda of the recent Third International Climate Services Conference, held in Montego Bay, Jamaica, 4–6 December 2013. Issues and challenges concerning a demand led approach to serve the health sector needs, were identified and analysed. Important recommendations emerged to ensure that innovative collaboration between climate and health services assist decision-making processes and the management of climate-sensitive health risk. Key recommendations included: a move from risk assessment towards risk management; the engagement of the public health community with both the climate sector and development sectors, whose decisions impact on health, particularly the most vulnerable; to increase operational research on the use of policy-relevant climate information to manage climate- sensitive health risks; and to develop in-country capacities to improve local knowledge (including collection of epidemiological, climate and socio-economic data), along with institutional interaction with policy makers.
An Interactive Wireless Communication System for Visually Impaired People Using City Bus Transport
Authors: Wang Hsiao-Lan , Chen Ya-Ping , Rau Chi-Lun , Yu Chung-Huang
Published: April 2014

Visually impaired people have difficulty accessing information about public transportation systems. Several systems have been developed for assisting visually impaired and blind people to use the city bus. Most systems provide only one-way communication and require high-cost and complex equipment. The purpose of this study is to reduce the difficulties faced by visually impaired people when taking city buses, using an interactive wireless communication system. The system comprised a user module and a bus module to establish a direct one-to-one connection. When the user inputs 4-digit numbers, the user module immediately sends out the information. If the bus module receives the matched bus number, it buzzes and the warning LED flashes to notify the bus driver that someone is waiting to board on the bus. User tests were conducted by two visually impaired people in a simulated vehicle and a city bus. The success rate of interactive wireless communication, recognizing the arrival of the bus and boarding the correct bus reached 100% in all of the tests. The interactive wireless communication aid system is a valid and low-cost device for assisting visually impaired people to use city buses.
Potential Activity of Fevicordin-A from Phaleria macrocarpa (Scheff) Boerl. Seeds as Estrogen Receptor Antagonist Based on Cytotoxicity and Molecular Modelling Studies
Authors: Muchtaridi Muchtaridi , Yusuf Muhammad , Diantini Ajeng , Choi Sy , Al-Najjar Belal , Manurung Jerry , Subarnas Anas , Achmad Tri , Wardhani Savitri , Wahab Habibah
Published: April 2014

Fevicordin-A (FevA) isolated from Phaleria macrocarpa (Scheff) Boerl. seeds was evaluated for its potential anticancer activity by in vitro and in silico approaches. Cytotoxicity studies indicated that FevA was selective against cell lines of human breast adenocarcinoma (MCF-7) with an IC50 value of 6.4 µM. At 11.2 µM, FevA resulted in 76.8% cell death of T-47D human breast cancer cell lines. Critical pharmacophore features amongst human Estrogen Receptor-α (hERα) antagonists were conserved in FevA with regard to a hypothesis that they could make notable contributions to its pharmacological activity. The binding stability as well as the dynamic behavior of FevA towards the hERα receptor in agonist and antagonist binding sites were probed using molecular dynamics (MD) simulation approach. Analysis of MD simulation suggested that the tail of FevA was accountable for the repulsion of the C-terminal of Helix-11 (H11) in both agonist and antagonist receptor forms. The flexibility of loop-534 indicated the ability to disrupt the hydrogen bond zipper network between H3 and H11 in hERα. In addition, MM/GBSA calculation from the molecular dynamic simulations also revealed a stronger binding affinity of FevA in antagonistic action as compared to that of agonistic action. Collectively, both the experimental and computational results indicated that FevA has potential as a candidate for an anticancer agent, which is worth promoting for further preclinical evaluation.
Recent Advances in Bacteria Identification by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Using Nanomaterials as Affinity Probes
Authors: Chiu Tai-Chia
Published: April 2014

Identifying trace amounts of bacteria rapidly, accurately, selectively, and with high sensitivity is important to ensuring the safety of food and diagnosing infectious bacterial diseases. Microbial diseases constitute the major cause of death in many developing and developed countries of the world. The early detection of pathogenic bacteria is crucial in preventing, treating, and containing the spread of infections, and there is an urgent requirement for sensitive, specific, and accurate diagnostic tests. Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is an extremely selective and sensitive analytical tool that can be used to characterize different species of pathogenic bacteria. Various functionalized or unmodified nanomaterials can be used as affinity probes to capture and concentrate microorganisms. Recent developments in bacterial detection using nanomaterials-assisted MALDI-MS approaches are highlighted in this article. A comprehensive table listing MALDI-MS approaches for identifying pathogenic bacteria, categorized by the nanomaterials used, is provided.
Efficient Delivery of Plasmid DNA Using Cholesterol-Based Cationic Lipids Containing Polyamines and Ether Linkages
Authors: Kim Bieong-Kil , Seu Young-Bae , Bae Yun-Ui , Kwak Tae-Won , Kang Hyungu , Moon Ik-Jae , Hwang Guen-Bae , Park So-Young , Doh Kyung-Oh
Published: April 2014

Cationic liposomes are broadly used as non-viral vectors to deliver genetic materials that can be used to treat various diseases including cancer. To circumvent problems associated with cationic liposome-mediated delivery systems such as low transfection efficiency and serum-induced inhibition, cholesterol-based cationic lipids have been synthesized that resist the effects of serum. The introduction of an ether-type linkage and extension of the aminopropyl head group on the cholesterol backbone increased the transfection efficiency and DNA binding affinity compared to a carbamoyl-type linkage and a mono aminopropyl head group, respectively. Under optimal conditions, each liposome formulation showed higher transfection efficiency in AGS and Huh-7 cells than commercially available cationic liposomes, particularly in the presence of serum. The following molecular structures were found to have a positive effect on transfection properties: (i) extended aminopropyl head groups for a strong binding affinity to plasmid DNA; (ii) an ether linkage that favors electrostatic binding to plasmid DNA; and (iii) a cholesterol backbone for serum resistance.
Corrosion of Bronzes by Extended Wetting with Single versus Mixed Acidic Pollutants
Authors: Gianni Liliana , Gigante Giovanni , Cavallini Mauro , Adriaens Annemie
Published: April 2014

The corrosion of bronzes was examined in the context of single-acid versus mixed-acid (as in urban acid rain) solutions. Two bi-component bronzes (copper with either 3% Sn or 7% Sn) that closely represent those of historic artifacts were immersed for five weeks in conditions designed to replicate those experienced by statues and ornaments in cities where rainfall and humidity constantly produce an electrolyte layer on the surfaces of bronzes. Ions, acids, and particles of pollutants can dissolve in this layer, resulting in a variety of harsh corrosion processes. The kinetics of corrosion and the properties of the resulting patinas were monitored weekly by electrochemical impedance spectroscopy and open-circuit potential measurements. The sizes and appearances of the corrosion products were monitored and used to estimate the progress of the corrosion, whose crystalline structures were visualized using scanning electron microscopy with energy dispersive spectroscopy, identified by X-ray diffraction, and characterized by spectrocolorimetry. The electrochemical measurements demonstrated that greater damage (in terms of color change and corrosion product formation) did not correspond to deficiencies in protection. The mixed-acid solution did not corrode the bronzes, as would be expected from the additive effects of the single acids. The postulated mechanisms of metal dissolution appear to be specific to a particular bronze alloy, with the tin component playing an important role.
Optical Systems for Ultra-High-Speed TDM Networking
Authors: Galili Michael , Hu Hao , Mulvad Hans , Medhin Ashenafi , Clausen Anders , Oxenløwe Leif
Published: April 2014

This paper discusses key results in the field of high speed optical networking with particular focus on packet-based systems. Schemes for optical packet labeling, packet switching and packet synchronization will be discussed, along with schemes for optical clock recovery, channel identification and detection of ultra-high-speed optical signals.
Allometric Scaling and Resource Limitations Model of Tree Heights: Part 3. Model Optimization and Testing over Continental China
Authors: Ni Xiliang , Park Taejin , Choi Sungho , Shi Yuli , Cao Chunxiang , Wang Xuejun , Lefsky Michael , Simard Marc , Myneni Ranga
Published: April 2014

The ultimate goal of our multi-article series is to demonstrate the Allometric Scaling and Resource Limitation (ASRL) approach for mapping tree heights and biomass. This third article tests the feasibility of the optimized ASRL model over China at both site (14 meteorological stations) and continental scales. Tree heights from the Geoscience Laser Altimeter System (GLAS) waveform data are used for the model optimizations. Three selected ASRL parameters (area of single leaf, α; exponent for canopy radius, η; and root absorption efficiency, γ) are iteratively adjusted to minimize differences between the references and predicted tree heights. Key climatic variables (e.g., temperature, precipitation, and solar radiation) are needed for the model simulations. We also exploit the independent GLAS and in situ tree heights to examine the model performance. The predicted tree heights at the site scale are evaluated against the GLAS tree heights using a two-fold cross validation (RMSE = 1.72 m; R2 = 0.97) and bootstrapping (RMSE = 4.39 m; R2 = 0.81). The modeled tree heights at the continental scale (1 km spatial resolution) are compared to both GLAS (RMSE = 6.63 m; R2 = 0.63) and in situ (RMSE = 6.70 m; R2 = 0.52) measurements. Further, inter-comparisons against the existing satellite-based forest height maps have resulted in a moderate degree of agreements. Our results show that the optimized ASRL model is capable of satisfactorily retrieving tree heights over continental China at both scales. Subsequent studies will focus on the estimation of woody biomass after alleviating the discussed limitations.
Object-Based Greenhouse Classification from GeoEye-1 and WorldView-2 Stereo Imagery
Authors: Aguilar Manuel , Bianconi Francesco , Aguilar Fernando , Fernández Ismael
Published: April 2014

Remote sensing technologies have been commonly used to perform greenhouse detection and mapping. In this research, stereo pairs acquired by very high-resolution optical satellites GeoEye-1 (GE1) and WorldView-2 (WV2) have been utilized to carry out the land cover classification of an agricultural area through an object-based image analysis approach, paying special attention to greenhouses extraction. The main novelty of this work lies in the joint use of single-source stereo-photogrammetrically derived heights and multispectral information from both panchromatic and pan-sharpened orthoimages. The main features tested in this research can be grouped into different categories, such as basic spectral information, elevation data (normalized digital surface model; nDSM), band indexes and ratios, texture and shape geometry. Furthermore, spectral information was based on both single orthoimages and multiangle orthoimages. The overall accuracy attained by applying nearest neighbor and support vector machine classifiers to the four multispectral bands of GE1 were very similar to those computed from WV2, for either four or eight multispectral bands. Height data, in the form of nDSM, were the most important feature for greenhouse classification. The best overall accuracy values were close to 90%, and they were not improved by using multiangle orthoimages.
Classifying Complex Mountainous Forests with L-Band SAR and Landsat Data Integration: A Comparison among Different Machine Learning Methods in the Hyrcanian Forest
Authors: Attarchi Sara , Gloaguen Richard
Published: April 2014

Forest environment classification in mountain regions based on single-sensor remote sensing approaches is hindered by forest complexity and topographic effects. Temperate broadleaf forests in western Asia such as the Hyrcanian forest in northern Iran have already suffered from intense anthropogenic activities. In those regions, forests mainly extend in rough terrain and comprise different stand structures, which are difficult to discriminate. This paper explores the joint analysis of Landsat7/ETM+, L-band SAR and their derived parameters and the effect of terrain corrections to overcome the challenges of discriminating forest stand age classes in mountain regions. We also verified the performances of three machine learning methods which have recently shown promising results using multisource data; support vector machines (SVM), neural networks (NN), random forest (RF) and one traditional classifier (i.e., maximum likelihood classification (MLC)) as a benchmark. The non-topographically corrected ETM+ data failed to differentiate among different forest stand age classes (average classification accuracy (OA) = 65%). This confirms the need to reduce relief effects prior data classification in mountain regions. SAR backscattering alone cannot properly differentiate among different forest stand age classes (OA = 62%). However, textures and PolSAR features are very efficient for the separation of forest classes (OA = 82%). The highest classification accuracy was achieved by the joint usage of SAR and ETM+ (OA = 86%). However, this shows a slight improvement compared to the ETM+ classification (OA = 84%). The machine learning classifiers proved t o be more robust and accurate compared to MLC. SVM and RF statistically produced better classification results than NN in the exploitation of the considered multi-source data.
Long-Term Land Subsidence Monitoring of Beijing (China) Using the Small Baseline Subset (SBAS) Technique
Authors: Hu Bo , Wang Han-Sheng , Sun Yong-Ling , Hou Jian-Guo , Liang Jun
Published: April 2014

Advanced techniques of multi-temporal InSAR (MT-InSAR) represent a valuable tool in ground subsidence studies allowing remote investigation of the behavior of mass movements in long time intervals by using large datasets of SAR images covering the same area and acquired at different epochs. Beijing is susceptible to subsidence, producing undesirable environmental impacts and affecting dense population. Excessive groundwater withdrawal is thought to be the primary cause of land subsidence, and rapid urbanization and economic development, mass construction of skyscrapers, highways and underground engineering facilities (e.g., subway) are also contributing factors. In this paper, a spatial–temporal analysis of the land subsidence in Beijing was performed using one of the MT-InSAR techniques, referred to as Small Baseline Subset (SBAS). This technique allows monitoring the temporal evolution of a deformation phenomenon, via the generation of mean deformation velocity maps and displacement time series from a data set of acquired SAR images. 52 C-band ENVISAT ASAR images acquired from June 2003 to August 2010 were used to produce a linear deformation rate map and to derive time series of ground deformation. The results show that there are three large subsidence funnels within this study area, which separately located in Balizhuang-Dajiaoting in Chaoyang district, Wangjing-Laiguangying Chaoyang district, Gaoliying Shunyi district. The maximum settlement center is Wangsiying-Tongzhou along the Beijing express; the subsidence velocity exceeds 110 mm/y in the LOS direction. In particular, we compared the achieved results with leveling measurements that are assumed as reference. The estimated long-term subsidence results obtained by SBAS approach agree well with the development of the over-exploitation of ground water, indicating that SBAS techniques is adequate for the retrieval of land subsidence in Beijing from multi-temporal SAR data.
Detection and Characterization of Hedgerows Using TerraSAR-X Imagery
Authors: Betbeder Julie , Nabucet Jean , Pottier Eric , Baudry Jacques , Corgne Samuel , Hubert-Moy Laurence
Published: April 2014

Whilst most hedgerow functions depend upon hedgerow structure and hedgerow network patterns, in many ecological studies information on the fragmentation of hedgerows network and canopy structure is often retrieved in the field in small areas using accurate ground surveys and estimated over landscapes in a semi-quantitative manner. This paper explores the use of radar SAR imagery to (i) detect hedgerow networks; and (ii) describe the hedgerow canopy heterogeneity using TerraSAR-X imagery. The extraction of hedgerow networks was achieved using an object-oriented method using two polarimetric parameters: the Single Bounce and the Shannon Entropy derived from one TerraSAR-X image. The hedgerow canopy heterogeneity estimated from field measurements was compared with two backscattering coefficients and three polarimetric parameters derived from the same image. The results show that the hedgerow network and its fragmentation can be identified with a very good accuracy (Kappa index: 0.92). This study also reveals the high correlation between one polarimetric parameter, the Shannon entropy, and the canopy fragmentation measured in the field. Therefore, VHSR radar images can both precisely detect the presence of wooded hedgerow networks and characterize their structure, which cannot be achieved with optical images.
Surface Temperatures at the Continental Scale: Tracking Changes with Remote Sensing at Unprecedented Detail
Authors: Metz Markus , Rocchini Duccio , Neteler Markus
Published: April 2014

Temperature is a main driver for most ecological processes, and temperature time series provide key environmental indicators for various applications and research fields. High spatial and temporal resolutions are crucial for detailed analyses in various fields of research. A disadvantage of temperature data obtained by satellites is the occurrence of gaps that must be reconstructed. Here, we present a new method to reconstruct high-resolution land surface temperature (LST) time series at the continental scale gaining 250-m spatial resolution and four daily values per pixel. Our method constitutes a unique new combination of weighted temporal averaging with statistical modeling and spatial interpolation. This newly developed reconstruction method has been applied to greater Europe, resulting in complete daily coverage for eleven years. To our knowledge, this new reconstructed LST time series exceeds the level of detail of comparable reconstructed LST datasets by several orders of magnitude. Studies on emerging diseases, parasite risk assessment and temperature anomalies can now be performed on the continental scale, maintaining high spatial and temporal detail. We illustrate a series of applications in this paper. Our dataset is available online for download as time aggregated derivatives for direct usage in GIS-based applications.
A Comparative Study of Information-Based Source Number Estimation Methods and Experimental Validations on Mechanical Systems
Authors: Cheng Wei , Zhang Zhousuo , Cao Hongrui , He Zhengjia , Zhu Guanwen
Published: April 2014

This paper investigates one eigenvalue decomposition-based source number estimation method, and three information-based source number estimation methods, namely the Akaike Information Criterion (AIC), Minimum Description Length (MDL) and Bayesian Information Criterion (BIC), and improves BIC as Improved BIC (IBIC) to make it more efficient and easier for calculation. The performances of the abovementioned source number estimation methods are studied comparatively with numerical case studies, which contain a linear superposition case and a both linear superposition and nonlinear modulation mixing case. A test bed with three sound sources is constructed to test the performances of these methods on mechanical systems, and source separation is carried out to validate the effectiveness of the experimental studies. This work can benefit model order selection, complexity analysis of a system, and applications of source separation to mechanical systems for condition monitoring and fault diagnosis purposes.
An Adaptive Scheme for Robot Localization and Mapping with Dynamically Configurable Inter-Beacon Range Measurements
Authors: Torres-González Arturo , Martinez-de Dios Jose , Ollero Anibal
Published: April 2014

This work is motivated by robot-sensor network cooperation techniques where sensor nodes (beacons) are used as landmarks for range-only (RO) simultaneous localization and mapping (SLAM). This paper presents a RO-SLAM scheme that actuates over the measurement gathering process using mechanisms that dynamically modify the rate and variety of measurements that are integrated in the SLAM filter. It includes a measurement gathering module that can be configured to collect direct robot-beacon and inter-beacon measurements with different inter-beacon depth levels and at different rates. It also includes a supervision module that monitors the SLAM performance and dynamically selects the measurement gathering configuration balancing SLAM accuracy and resource consumption. The proposed scheme has been applied to an extended Kalman filter SLAM with auxiliary particle filters for beacon initialization (PF-EKF SLAM) and validated with experiments performed in the CONET Integrated Testbed. It achieved lower map and robot errors (34% and 14%, respectively) than traditional methods with a lower computational burden (16%) and similar beacon energy consumption.
Muecas: A Multi-Sensor Robotic Head for Affective Human Robot Interaction and Imitation
Authors: Cid Felipe , Moreno Jose , Bustos Pablo , Núñez Pedro
Published: April 2014

This paper presents a multi-sensor humanoid robotic head for human robot interaction. The design of the robotic head, Muecas, is based on ongoing research on the mechanisms of perception and imitation of human expressions and emotions. These mechanisms allow direct interaction between the robot and its human companion through the different natural language modalities: speech, body language and facial expressions. The robotic head has 12 degrees of freedom, in a human-like configuration, including eyes, eyebrows, mouth and neck, and has been designed and built entirely by IADeX (Engineering, Automation and Design of Extremadura) and RoboLab. A detailed description of its kinematics is provided along with the design of the most complex controllers. Muecas can be directly controlled by FACS (Facial Action Coding System), the de facto standard for facial expression recognition and synthesis. This feature facilitates its use by third party platforms and encourages the development of imitation and of goal-based systems. Imitation systems learn from the user, while goal-based ones use planning techniques to drive the user towards a final desired state. To show the flexibility and reliability of the robotic head, the paper presents a software architecture that is able to detect, recognize, classify and generate facial expressions in real time using FACS. This system has been implemented using the robotics framework, RoboComp, which provides hardware-independent access to the sensors in the head. Finally, the paper presents experimental results showing the real-time functioning of the whole system, including recognition and imitation of human facial expressions.
Design and Implementation of Practical Bidirectional Texture Function Measurement Devices Focusing on the Developments at the University of Bonn
Authors: Schwartz Christopher , Sarlette Ralf , Weinmann Michael , Rump Martin , Klein Reinhard
Published: April 2014

Understanding as well as realistic reproduction of the appearance of materials play an important role in computer graphics, computer vision and industry. They enable applications such as digital material design, virtual prototyping and faithful virtual surrogates for entertainment, marketing, education or cultural heritage documentation. A particularly fruitful way to obtain the digital appearance is the acquisition of reflectance from real-world material samples. Therefore, a great variety of devices to perform this task has been proposed. In this work, we investigate their practical usefulness. We first identify a set of necessary attributes and establish a general categorization of different designs that have been realized. Subsequently, we provide an in-depth discussion of three particular implementations by our work group, demonstrating advantages and disadvantages of different system designs with respect to the previously established attributes. Finally, we survey the existing literature to compare our implementation with related approaches.
Vegetation in Bangalore’s Slums: Boosting Livelihoods, Well-Being and Social Capital
Authors: Gopal Divya , Nagendra Harini
Published: April 2014

Urban greenery provides ecosystem services that play an important role in the challenging context of urban deprivation and poverty. This study assesses the social importance of vegetation through empirical assessment of 44 urban slums in the rapidly developing southern city of Bangalore, India. Vegetation played a major role in supporting nutrition by its role in food consumption, and in promoting health through the planting of species with medicinal use. Trees in slums also formed nodes for social activities including conversing and playing, domestic activities such as cooking and washing dishes, and livelihood activities such as the manufacture of broomsticks and tyre repair. Innovative methods of gardening were widely adopted, with kitchen gardens found planted in plastic bags, paint cans, old kitchen utensils and buckets, indicating the importance given to planting in environments with limited finances. Short and narrow trunked trees with medium-sized canopies and high economic value, such as Pongamia, were preferred. A greater focus on greening in slums is needed, and can provide an invaluable, inexpensive and sustainable approach to improve lives in these congested, deprived environments.
Immune Adjuvant Effect of Molecularly-defined Toll-Like Receptor Ligands
Authors: Toussi Deana , Massari Paola
Published: April 2014

Vaccine efficacy is optimized by addition of immune adjuvants. However, although adjuvants have been used for over a century, to date, only few adjuvants are approved for human use, mostly aimed at improving vaccine efficacy and antigen-specific protective antibody production. The mechanism of action of immune adjuvants is diverse, depending on their chemical and molecular nature, ranging from non-specific effects (i.e., antigen depot at the immunization site) to specific activation of immune cells leading to improved host innate and adaptive responses. Although the detailed molecular mechanism of action of many adjuvants is still elusive, the discovery of Toll-like receptors (TLRs) has provided new critical information on immunostimulatory effect of numerous bacterial components that engage TLRs. These ligands have been shown to improve both the quality and the quantity of host adaptive immune responses when used in vaccine formulations targeted to infectious diseases and cancer that require both humoral and cell-mediated immunity. The potential of such TLR adjuvants in improving the design and the outcomes of several vaccines is continuously evolving, as new agonists are discovered and tested in experimental and clinical models of vaccination. In this review, a summary of the recent progress in development of TLR adjuvants is presented.
Active audiences in the regulation of the audiovisual media. Consumer versus citizen in Spain and Mexico
Authors: Fuente-Cobo Carmen , Martínez-Otero Juan-María , del-Prado-Flores Rogelio
Published: April 2014

Media audience has been conceived, traditionally, as a group of citizens or consumers. In the Media environment, citizens exercise their communication rights and participate in the public sphere; consumers, on the other hand, consume audiovisual products in a specific market. In the citizen perspective, audiovisual communication serves the public interest and democratic values; in the consumer one, it serves private and individual interests. This paper studies the main academic positions referred to the dichotomy citizen – consumer, attending particularly to the investigations of Peter Dahlgren on relations between Media and Democracy; of Richard Collins, on Audiovisual Policy; and of Sonia Livingstone on public sphere, audience participation and Media governance. After this theoretical approach, the paper analyzes the presence of these conceptions of the audience in the audiovisual legal systems of two countries: Spain and Mexico. These two countries are modifying their legal framework. As a conclusion, it appears that the different conceptions of the audience –as consumers or as citizens– are in a close relationship with the different ways of Media control and accountability.

Dos han sido los prismas bajo los que se ha concebido tradicionalmente a la audiencia: como ciudadanos, que ante los mensajes de los medios ejercen sus derechos comunicativos y participan en la construcción de una opinión pública libre; o como consumidores o usuarios, que actúan dentro de un mercado de productos audiovisuales. Mientras que la primera perspectiva atiende a la comunicación audiovisual valorando su interés público y su influencia en la construcción de un espacio público de debate y discusión, la segunda atiende a la dimensión más privada e individual de la comunicación audiovisual. En el presente trabajo se abordan las principales posiciones doctrinales sobre dicha dicotomía consumidor-ciudadano, analizando para ello la obra de los autores que más atención han dedicado a estas cuestiones en el ámbito europeo, y en especial los trabajos de Peter Dahlgren sobre las relaciones entre medios y democracia, los de Richard Collins sobre política audiovisual, y los vinculados a Sonia Livingstone sobre esfera pública, participación de las audiencias y gobernanza de los medios. Realizada esta aproximación teórica, se analiza la presencia de dichas concepciones de la audiencia en dos ordenamientos jurídicos audiovisuales que están experimentando modificaciones sustanciales: el español y el mexicano. Como conclusión, se constata que las distintas concepciones de la audiencia están en profunda relación con la forma de concebir el control de los medios y la rendición de cuentas de sus operadores frente al público.
The digital divide in the university: The appropriation of ICT in Higher Education students from Bogota, Colombia
Authors: Berrío-Zapata Cristian , Rojas-Hernández Hernando
Published: April 2014

The growth and integration of ICTs in the global economy has created conditions that profoundly affect our society, dividing communities between those who effectively appropriate these resources and those who do not, the «digital divide». This exploratory study seeks to propose and validate ways of assessing this phenomenon in higher education, from the construction of a model and comprehensive methodology that values contextual conditions, in addition to measuring access factors and motivation for use, that have been employed in previous research. To obtain indications about the behavior of this phenomenon, we developed research with students from three universities in Bogota, administering 566 surveys in four phases that would test the variables proposed in the model. The results show that the variables of the model link causally, with the strongest relations between education, attitude towards ICTs and ICT application. Although students have good access to ICTs and high levels of education, no strong relationship was found in regards to «perceived impact on production». This may be explained by a superficial appropriation of ICT, due to a context that is alien to its conditions of origin (industrialism, innovation), poor quality of education and economies not centered around R&D.

El crecimiento e inserción de las tecnologías de la comunicación (TIC) en la economía mundial, ha generado condiciones que afectan profundamente a nuestra sociedad, dividiéndola entre comunidades que apropian efectivamente estos recursos y aquellos que no lo hacen, situación denominada «brecha digital». Este estudio exploratorio buscó proponer y validar formas de evaluación de tal fenómeno en la educación superior, a partir de la construcción de un modelo y metodología integral que atiendan a las condiciones de contexto, en adición a la medición de elementos de acceso y motivación de uso ya utilizadas en investigaciones anteriores. Se trabajó con estudiantes de tres Universidades de Bogotá para obtener indicios con respecto al comportamiento del fenómeno. 566 encuestas fueron administradas en cuatro fases para probar las variables propuestas por el modelo. Los resultados muestran que las variables del modelo se relacionan de manera encadenada y escalonada; la relación más fuerte se dio entre educación, actitud frente a las TIC y su aplicación. Aun cuando los estudiantes encuestados tienen condiciones óptimas de acceso y formación, no se encontró una relación fuerte con la percepción de impacto productivo; esto puede deberse a una apropiación superficial de las TIC producto de un contexto extraño a sus condiciones de origen (industrialismo, innovación), educación de calidad pobre y economías no centradas en I+D.
Procter & gamble, Edificio Administrativo - Schwalbach. Alemania Federal
Authors: Hentrich-Petschnigg & Partner Arquitectos
Published: April 2014

Próximo a Frankfort, sobre un gran solar de bellas panorámicas, se ha levantado este elegante edificio, que consta de: sótano, una extensa planta baja de carácter representativo y social (salones, vestíbulo, cafetería, etc.); bloque en estrella, de seis plantas, con las circulaciones verticales y los aseos en el centro, destinado, fundamentalmente, a oficinas. En un cuerpo rectangular separado se disponen las instalaciones y calderas. Un espacioso jardín y la zona de aparcamientos completan la ocupación del terreno, en el cual está prevista la posibilidad de cuadruplicar el volumen actualmente edificado. Las plantas se han distribuido con un módulo básico de 1,50 x X 1,50 m.
Construcción fundamental, a base de: estructura metálica, forjados de hormigón sobre encofrados metálicos, cerramientos de hormigón revestido de granito rojo, cristales dobles, parasoles interiores verticales, suelos enmoquetados y aire acondicionado.
Viaducto de Chonta en la autopista Bilbao-Behobia – España
Authors: Aparicio G.
Published: April 2014

Situado en la autopista Bilbao-Behobia, a su paso por Eibar, presenta un trazado en curva y soporta dos calzadas de 11,50 m de anchura. El tablero está constituido por dos tramos ménsula, de 52 m cada uno, fabricados in situ, y por otros dos, de 43 m, formados por cinco vigas prefabricadas pretensadas; los dos estribos son tradicionales.
Destacamos la curiosa construcción de los encofrados, para los tramos in situ, y el lanzamiento de las vigas de 43 m con carro Sicet de 120 t y 45 m, realizada por Ferrovial, S. A.
Las pilas inclinadas —18 m de separación de medianas en su parte alta y 4 en cimientos— son, sin embargo, la nota más original e interesante de esta obra, ya que para poder utilizar los encofrados deslizantes y evitar la construcción de apeos costosos y entorpecedores del tráfico inferior se realizaron en posición vertical, abriéndose, posteriormente, con giro sobre rótulas metálicas. Con este tipo de pilas se reduce la luz inicial de 95 m a 77 m.
Rampa de esquí olímpica en Oberstdorf – Austria
Authors: Editorial Equipo
Published: April 2014

Esta airosa construcción deportiva —la mayor de! mundo en su especie— ha sido realizada a base de hormigón ligero pretensado, anclando fuertemente en la roca la base maciza, de 22 m, que soporta el brazo posterior, cuya proyección horizontal es de 57,80 m. Por el interior de su sección en cajón, con anchura de 2,50 m y altura variable, desde 3,45 m a 10,25 m, transcurre una escalera y una cabina deslizante paralelas. De la parte baja arranca un tablero independiente, apoyado sobre cinco soportes verticales, todo ello también de hormigón armado ligero.
Se han obtenido las máximas utilidad y economía que proporciona este material, después de un minucioso estudio y de cuidadosos cálculos.
Han intervenido en la obra las empresas Dyckerhoff & Widmann y Alfred Kunz & Co., la Oficina de Arquitectura Horle, de Oberstdorf, y los ingenieros Profs. Knittel, Kupfer y Jelinek, con el Dr. Werner; todos ellos de Munich.
Breve estudio comparativo de los modernos medios de transporte terrestre
Authors: De Andrés Conde M. Carmen
Published: April 2014

En este estudio se recopilan y comparan una serie de datos actualmente disponibles sobre modernos medios de transporte terrestre, con objeto de facilitar la elección del más adecuado en cada caso.
Para ayudar a la comprensión de sus condiciones de explotación, se han resumido en las definiciones las características conocidas más destacadas de cada uno de ellos, ordenándolos por orden alfabético.
A partir de algunas de estas características de explotación, como velocidad y capacidad, se han obtenido criterios sobre el campo de aplicación de cada medio de transporte.
Dos obras de la oficina técnica Piguet Ingenieros Cs., S.A.
Authors: Editorial Equipo
Published: April 2014

En este artículo se describen:
1. Dos puentes rectilíneos independientes, mediante los cuales la autopista del Léman N 9 franquea el valle de la Paudèze. Tienen ambos unos 400 m de longitud y una anchura de 12 m, que se componen de dos vías de circulación y una banda de estacionamiento. Altura máxima de 70 m y media de 30 m. Es de destacar que las características de la región molásica del Belmont presentaba unas condiciones geológicas desastrosas, por lo que la cimentación fue motivo de un minucioso y prudente estudio. Todo lo citado anteriormente aconsejó convocar un concurso de proyectos, del que fue ganador el que aquí presentamos.
2. El puente del Lendar, entre Belmont y La Croix, es una corrección de la RC 773, que franquea la RC770.
A fin de evitar cargas excesivas sobre un terreno que presentaba las mismas deficientes características que se han mencionado para los puentes de la Paudèze, se ha construido en curva, a fin de no ceñirse al terraplén, el cual ha sido sujetado mediante un muro de contención de hormigón armado. El puente tiene una longitud total de 152 m —distribuidos en cuatro tramos — y una anchura de 15,60 m.
Ambas obras son de hormigón pretensado.