bluuebunny/crossref_metadata_2025 huggingface dataset:
One-Step Synthesis of Metal/Oxide Nanocomposites by Gas Phase Condensation
Authors: Patelli Nicola , Migliori Andrea , Morandi Vittorio , Pasquini Luca
Published: February 2019

Metallic nanoparticles (NPs), either supported on a porous oxide framework or finely dispersed within an oxide matrix, find applications in catalysis, plasmonics, nanomagnetism and energy conversion, among others. The development of synthetic routes that enable to control the morphology, chemical composition, crystal structure and mutual interaction of metallic and oxide phases is necessary in order to tailor the properties of this class of nanomaterials. With this work, we aim at developing a novel method for the synthesis of metal/oxide nanocomposites based on the assembly of NPs formed by gas phase condensation of metal vapors in a He/O2 atmosphere. This new approach relies on the independent evaporation of two metallic precursors with strongly different oxidation enthalpies. Our goal is to show that the precursor with less negative enthalpy gives birth to metallic NPs, while the other to oxide NPs. The selected case study for this work is the synthesis of a Fe-Co/TiOx nanocomposite, a system of great interest for its catalytic and magnetic properties. By exploiting the new concept, we achieve the desired target, i.e., a nanoscale dispersion of metallic alloy NPs within titanium oxide NPs, the structure of which can be tailored into TiO1-δ or TiO2 by controlling the synthesis and processing atmosphere. The proposed synthesis technique is versatile and scalable for the production of many NPs-assembled metal/oxide nanocomposites.
Origin of Room-Temperature Ferromagnetism in Hydrogenated Epitaxial Graphene on Silicon Carbide
Authors: Ridene Mohamed , Najafi Ameneh , Flipse Kees
Published: February 2019

The discovery of room-temperature ferromagnetism of hydrogenated epitaxial graphene on silicon carbide challenges for a fundamental understanding of this long-range phenomenon. Carbon allotropes with their dispersive electron states at the Fermi level and a small spin-orbit coupling are not an obvious candidate for ferromagnetism. Here we show that the origin of ferromagnetism in hydrogenated epitaxial graphene with a relatively high Curie temperature (>300 K) lies in the formation of curved specific carbon site regions in the graphene layer, induced by the underlying Si-dangling bonds and by the hydrogen bonding. Hydrogen adsorption is therefore more favourable at only one sublattice site, resulting in a localized state at the Fermi energy that can be attributed to a pseudo-Landau level splitting. This n = 0 level forms a spin-polarized narrow band at the Fermi energy leading to a high Curie temperature and larger magnetic moment can be achieved due to the presence of Si dangling bonds underneath the hydrogenated graphene layer.
The Contribution of Magnetic Nanoparticles to Ferrogel Biophysical Properties
Authors: Blyakhman Felix A. , Makarova Emilia B. , Fadeyev Fedor A. , Lugovets Daiana V. , Safronov Alexander P. , Shabadrov Pavel A. , Shklyar Tatyana F. , Melnikov Grigory Yu. , Orue Iñaki , Kurlyandskaya Galina V.
Published: February 2019

Iron oxide γ-Fe2O3 magnetic nanoparticles (MNPs) were fabricated by laser target evaporation technique (LTE) and their structure and magnetic properties were studied. Polyacrylamide (PAAm) gels with different cross-linking density of the polymer network and polyacrylamide-based ferrogel with embedded LTE MNPs (0.34 wt.%) were synthesized. Their adhesive and proliferative potential with respect to human dermal fibroblasts were studied. At the same value of Young modulus, the adhesive and proliferative activities of the human dermal fibroblasts on the surface of ferrogel were unexpectedly much higher in comparison with the surface of PAAm gel. Properties of PAAm-100 + γ-Fe2O3 MNPs composites were discussed with focus on creation of a new generation of drug delivery systems combined in multifunctional devices, including magnetic field assisted delivery, positioning, and biosensing. Although exact applications are still under development, the obtained results show a high potential of LTE MNPs to be applied for cellular technologies and tissue engineering. PAAm-100 ferrogel with very low concentration of γ-Fe2O3 MNPs results in significant improvement of the cells’ compatibility to the gel-based scaffold.
A Robotic Recording and Playback Platform for Training Surgeons and Learning Autonomous Behaviors Using the da Vinci Surgical System
Authors: Pandya Abhilash , Eslamian Shahab , Ying Hao , Nokleby Matthew , Reisner Luke A.
Published: February 2019

This paper describes a recording and playback system developed using a da Vinci Standard Surgical System and research kit. The system records stereo laparoscopic videos, robot arm joint angles, and surgeon–console interactions in a synchronized manner. A user can then, on-demand and at adjustable speeds, watch stereo videos and feel recorded movements on the hand controllers of entire procedures or sub procedures. Currently, there is no reported comprehensive ability to capture expert surgeon movements and insights and reproduce them on hardware directly. This system has important applications in several areas: (1) training of surgeons, (2) collection of learning data for the development of advanced control algorithms and intelligent autonomous behaviors, and (3) use as a “black box” for retrospective error analysis. We show a prototype of such an immersive system on a clinically-relevant platform along with its recording and playback fidelity. Lastly, we convey possible research avenues to create better systems for training and assisting robotic surgeons.
Hierarchical Clustering-Aligning Framework Based Fast Large-Scale 3D Reconstruction Using Aerial Imagery
Authors: Xie Xiuchuan , Yang Tao , Li Dongdong , Li Zhi , Zhang Yanning
Published: February 2019

With extensive applications of Unmanned Aircraft Vehicle (UAV) in the field of remote sensing, 3D reconstruction using aerial images has been a vibrant area of research. However, fast large-scale 3D reconstruction is a challenging task. For aerial image datasets, large scale means that the number and resolution of images are enormous, which brings significant computational cost to the 3D reconstruction, especially in the process of Structure from Motion (SfM). In this paper, for fast large-scale SfM, we propose a clustering-aligning framework that hierarchically merges partial structures to reconstruct the full scene. Through image clustering, an overlapping relationship between image subsets is established. With the overlapping relationship, we propose a similarity transformation estimation method based on joint camera poses of common images. Finally, we introduce the closed-loop constraint and propose a similarity transformation-based hybrid optimization method to make the merged complete scene seamless. The advantage of the proposed method is a significant efficiency improvement without a marginal loss in accuracy. Experimental results on the Qinling dataset captured over Qinling mountain covering 57 square kilometers demonstrate the efficiency and robustness of the proposed method.
Precise Antenna Pointing Determination in Elevation for Spaceborne SAR Systems Using Coherent Pattern Differences
Authors: Reimann Jens , Schwerdt Marco , Schmidt Kersten , Klenk Patrick T. P. , Steinbrecher Ulrich , Breit Helko
Published: February 2019

The precise determination of the SAR (synthetic aperture radar) antenna pointing is an essential task initially performed during the commissioning phase of a spaceborne SAR system and is permanently monitored during the whole mission life-time. Besides a correct illumination of the scene during data acquisition, antenna pointing is required for proper compensation of the radiation pattern for radiometric correction during SAR data processing. The Amazon rainforest is a well-established target area for antenna pointing estimation in elevation as proven by many past and current SAR missions. Several new SAR systems are now proposed which are using long wavelengths, i.e., L- and P-bands, which will be implemented using reflector-based antenna systems. These reflectors have, in contrast to planar phased array antennas, no completely rigid connection to the satellite body and, hence, a more volatile antenna pointing. Due to the huge dimensions of such reflector antennas required for the envisaged long wavelengths and the finite stiffness of the boom, the antenna pointing may change significantly along the orbit. Such variation cannot be tracked using the common Amazon rainforest approach only, as this measurement opportunity exists only at two positions along the orbit (ascending and descending). Here, the performance of an alternative technique is presented which mitigates the influence of the underlying SAR scene by employing two coherent SAR datasets acquired simultaneously with different antenna patterns. This allows the use of amplitude and phase information for pointing estimation. No assumption upon the homogeneity of the underlying scene is required and, hence, pointing estimation becomes feasible at nearly any point along the orbit. This paper outlines the technique, describes simulation results and presents outcomes from first experimental acquisitions performed with the TerraSAR-X satellite.
Variability of the Great Whirl and Its Impacts on Atmospheric Processes
Authors: Wang Sen , Zhu Weijun , Ma Jing , Ji Jinlin , Yang Jingsong , Dong Changming
Published: February 2019

Using satellite remote sensing data and re-analysis products for the period of 1993–2015, the variation of a large anticyclonic eddy, the so-called Great Whirl (GW), located in the Northwest Indian Ocean off the coast of Somali, and its impacts on atmosphere were investigated. The GW is generated in early summer and decays in late fall every year. The center of the GW is located at 7.73°N, 53.20°E. The mean lifetime, sea level anomaly (SLA) difference, sea surface temperature anomaly (SSTA), radius, normalized vorticity, eddy kinetic energy (EKE), and deformation rate are 169 days, 0.07 m, 0.83 °C, 116.86 km, −0.53, 0.08 m 2 · s − 2 , and 0.58, respectively. All these variables exhibit interannual variations. Composite analyses show that the maximum values of sea surface temperature (SST), wind, and water vapor anomalies occur in the northwest of the GW center. The fitting coefficient between the SST and wind speed anomaly is 1.1, indicating that, corresponding to 1 °C increases of the SST, the wind speed increases by about 1.1 m · s − 1 , and the fitting coefficient between the SST and water vapor anomaly is 0.45, indicating that water vapor increases by about 0.45 mm in response to 1 °C increases in the SST. In the vertical direction, the maximum and minimum values of vertical velocity anomalies and vertical transport of transient zonal momentum occur over the GW at about 900 hPa, and wind speed anomalies occur at about 950 hPa. Both the positive transport anomalies of transient zonal momentum and the positive vertical velocity anomalies on the west side of the GW can accelerate the wind speed in the lower level.
An Unmixing-Based Bayesian Model for Spatio-Temporal Satellite Image Fusion in Heterogeneous Landscapes
Authors: Xue Jie , Leung Yee , Fung Tung
Published: February 2019

Studies of land surface dynamics in heterogeneous landscapes often require satellite images with a high resolution, both in time and space. However, the design of satellite sensors often inherently limits the availability of such images. Images with high spatial resolution tend to have relatively low temporal resolution, and vice versa. Therefore, fusion of the two types of images provides a useful way to generate data high in both spatial and temporal resolutions. A Bayesian data fusion framework can produce the target high-resolution image based on a rigorous statistical foundation. However, existing Bayesian data fusion algorithms, such as STBDF (spatio-temporal Bayesian data fusion) -I and -II, do not fully incorporate the mixed information contained in low-spatial-resolution pixels, which in turn might limit their fusion ability in heterogeneous landscapes. To enhance the capability of existing STBDF models in handling heterogeneous areas, this study proposes two improved Bayesian data fusion approaches, coined ISTBDF-I and ISTBDF-II, which incorporate an unmixing-based algorithm into the existing STBDF framework. The performance of the proposed algorithms is visually and quantitatively compared with STBDF-II using simulated data and real satellite images. Experimental results show that the proposed algorithms generate improved spatio-temporal-resolution images over STBDF-II, especially in heterogeneous areas. They shed light on the way to further enhance our fusion capability.
Integration of Multiple Spectral Indices and a Neural Network for Burned Area Mapping Based on MODIS Data
Authors: Ba Rui , Song Weiguo , Li Xiaolian , Xie Zixi , Lo Siuming
Published: February 2019

Since wildfires have occurred frequently in recent years, accurate burned area mapping is required for wildfire severity assessment and burned land reconstruction. Satellite remote sensing is an effective technology that can provide valuable information for wildfire assessment. However, the common approaches based on using a single satellite image to promptly detect the burned areas have low accuracy and limited applicability. This paper develops a new burned area mapping method that surpasses the detection accuracy of previous methods, while still using a single Moderate Resolution Imaging Spectroradiometer (MODIS) sensor image. The key innovation is integrating optimal spectral indices and a neural network algorithm. We used the traditional empirical formula method, multi-threshold method and visual interpretation method to extract the sample sets of five typical types (burned area, vegetation, cloud, bare soil, and cloud shadow) from the MODIS data of several wildfires in the American states of Nevada, Washington and California in 2016. Afterward, the separability index M was adopted to assess the capacity of seven spectral bands and 13 spectral indices to distinguish the burned area from four unburned land cover types. Based on the separability analysis between the burned area and unburned areas, the spectral indices with an M value higher than 1.0 were employed to generate the training sample sets that were assessed to have an overall accuracy of 98.68% and Kappa coefficient of 97.46%. Finally, we utilized a back-propagation neural network (BPNN) to learn the spectral differences of different types from the training sample sets and obtain the output burned area map. The proposed method was applied to three wildfire cases in the American states of Idaho, Nevada and Oregon in 2017. A comparison of detection results between the new MODIS-based burned area map and the reference burned area map compiled from Landsat-8 Operational Land Imager (OLI) data indicates that the proposed method can effectively exploit the spectral characteristics of various land cover types. Also, this new method can achieve higher accuracy with the reduction of commission error (CE, >10%) and omission error (OE, >6%) compared to the traditional empirical formula method. The new burned area mapping method could help managers and the public perform more effective wildfire assessments and emergency management.
Design and Development of a Bio-Inspired UHF Sensor for Partial Discharge Detection in Power Transformers
Authors: Nobrega Luiz A. M. M. , Xavier George V. R. , Aquino Marcus V. D. , Serres Alexandre J. R. , Albuquerque Camila C. R. , Costa Edson G.
Published: February 2019

In this paper, the design and development of a bio-inspired UHF sensor for partial discharge detection in power transformers is presented. The UHF sensor was developed for external use in dielectric windows of power transformers. For this purpose, a microstrip antenna was designed with a radiating element shape based on the leaf of the Jatropha mollissima (Pohl) Baill plant. Then, an epoxy coating and an aluminium enclosure were developed to protect the antenna against corrosion and to provide mechanical support, external noise immunity, and a lifetime compatibility with power transformers. In order to verify the electrical parameters of the developed sensor, measurements of the gain and the reflection coefficient were performed in an anechoic chamber. Lastly, the antenna sensitivity for denominated partial discharge (PD) detection was compared with the IEC 60270 standard method. For this purpose, simultaneous tests were carried out in a partial discharge generator setup, composed of an oil cell with needle-plane electrodes. The experimental tests demonstrated the effectiveness of the sensor for detecting PD signals with apparent charge values higher than 35 pC.
Wireless Sensor Network Combined with Cloud Computing for Air Quality Monitoring
Authors: Arroyo Patricia , Herrero José Luis , Suárez José Ignacio , Lozano Jesús
Published: February 2019

Low-cost air pollution wireless sensors are emerging in densely distributed networks that provide more spatial resolution than typical traditional systems for monitoring ambient air quality. This paper presents an air quality measurement system that is composed of a distributed sensor network connected to a cloud system forming a wireless sensor network (WSN). Sensor nodes are based on low-power ZigBee motes, and transmit field measurement data to the cloud through a gateway. An optimized cloud computing system has been implemented to store, monitor, process, and visualize the data received from the sensor network. Data processing and analysis is performed in the cloud by applying artificial intelligence techniques to optimize the detection of compounds and contaminants. This proposed system is a low-cost, low-size, and low-power consumption method that can greatly enhance the efficiency of air quality measurements, since a great number of nodes could be deployed and provide relevant information for air quality distribution in different areas. Finally, a laboratory case study demonstrates the applicability of the proposed system for the detection of some common volatile organic compounds, including: benzene, toluene, ethylbenzene, and xylene. Principal component analysis, a multilayer perceptron with backpropagation learning algorithm, and support vector machine have been applied for data processing. The results obtained suggest good performance in discriminating and quantifying the concentration of the volatile organic compounds.
Optimised Extraction of Trypsin Inhibitors from Defatted Gac (Momordica cochinchinensis Spreng) Seeds for Production of a Trypsin Inhibitor-Enriched Freeze Dried Powder
Authors: Le Anh V. , Parks Sophie E. , Nguyen Minh H. , Roach Paul D.
Published: February 2019

The seeds of the Gac fruit, Momordica cochinchinensis Spreng, are rich in trypsin inhibitors (TIs) but their optimal extraction and the effects of freeze drying are not established. This study aims to (1) compare aqueous solvents (DI water, 0.1 M NaCl, 0.02 M NaOH and ACN)/water/FA, 25:24:1) for extracting TIs from defatted Gac seed kernel powder, (2) to optimise the extraction in terms of solvent, time and material to solvent ratio and (3) to produce a TI-enriched freeze-dried powder (FD-TIP) with good characteristics. Based on the specific TI activity (TIA), the optimal extraction was 1 h using a ratio of 2.0 g of defatted powder in 30 mL of 0.05 M NaCl. The optimisation improved the TIA and specific TIA by 8% and 13%, respectively. The FD-TIP had a high specific TIA (1.57 ± 0.17 mg trypsin/mg protein), although it also contained saponins (43.6 ± 2.3 mg AE/g) and phenolics (10.5 ± 0.3 mg GAE/g). The FD-TIP was likely stable during storage due to its very low moisture content (0.43 ± 0.08%) and water activity (0.18 ± 0.07) and its ability to be easily reconstituted in water due to its high solubility index (92.4 ± 1.5%). Therefore, the optimal conditions for the extraction of TIs from defatted Gac seed kernel powder followed by freeze drying gave a high quality powder in terms of its highly specific TIA and physical properties.
Measuring Micrometers of Matter and Inventing Indices: Entangling Social Perception within Discrete and Continuous Measurements of Air Quality
Authors: Schmitt Edwin
Published: February 2019

Environmental protection agencies around the globe are establishing different methods for measuring particulates, and then integrating those measurements into a single air quality index with other pollutants. At the same time, scientific inquiry has also shifted to a theory of measurement that incorporates discrete and continuous measurement. This article reviews the relationship between discrete measurements and indices, while also speculating on the way that the continuous measurement of air pollution could stimulate awareness and action. The paper argues that continuous measurement must include the way people of different backgrounds perceive air pollution in their lives. After reviewing the methods of measuring particulates and their inclusion into various indices, the article argues that in order to take action to mitigate the health impacts of air pollution, we must allow for the social perception of air pollution to become entangled within our scientific measurements.
Assessing the Financial Sustainability of the Pension Plan in China: The Role of Fertility Policy Adjustment and Retirement Delay
Authors: Wang Huan , Huang Jianyuan , Yang Qi
Published: February 2019

Population aging is creating serious challenges for the sustainability of China’s pension system. To mitigate the adverse impact of the demographic shift, China has recently introduced fertility and retirement policy reforms. The research presented in this paper primarily evaluates the impacts of recent reforms on the financial sustainability of China’s Urban Employees’ Pension Plan (UEPP). By using the Leslie matrix and actuarial models, the financial sustainability of the UEPP from 2019 to 2070 is projected and evaluated under a set of assumed policy reform scenarios. The results indicate that an imbalance in the pension fund would occur in the early 2020s and then expand under existing policies. Fertility adjustment, retirement delay, or combination reforms would not fundamentally solve this financial crisis in the long term. When 100% of couples have a second child and the retirement age is increased to 65, the current and accumulated pension deficits would drop by 50.05–67.56% and 35.88–54.23% between 2040 and 2070, respectively. Supplementary policy measures should be designed to encourage childbearing and retirement delay, including family support policies and top-designed pension system reform policies.
Status of Background-Independent Coarse Graining in Tensor Models for Quantum Gravity
Authors: Eichhorn Astrid , Koslowski Tim , Pereira Antonio D.
Published: February 2019

A background-independent route towards a universal continuum limit in discrete models of quantum gravity proceeds through a background-independent form of coarse graining. This review provides a pedagogical introduction to the conceptual ideas underlying the use of the number of degrees of freedom as a scale for a Renormalization Group flow. We focus on tensor models, for which we explain how the tensor size serves as the scale for a background-independent coarse-graining flow. This flow provides a new probe of a universal continuum limit in tensor models. We review the development and setup of this tool and summarize results in the two- and three-dimensional case. Moreover, we provide a step-by-step guide to the practical implementation of these ideas and tools by deriving the flow of couplings in a rank-4-tensor model. We discuss the phenomenon of dimensional reduction in these models and find tentative first hints for an interacting fixed point with potential relevance for the continuum limit in four-dimensional quantum gravity.
Chaos Stabilization and Tracking Recovery of a Faulty Humanoid Robot Arm in a Cooperative Scenario
Authors: Khan Said G. , Bendoukha Samir , Abdelmalek Salem
Published: February 2019

Synchronised motion is an important requirement for two cooperating humanoid robot arms. In this work a cooperative scenario is considered where two humanoid robot arms (using 4DOF each, namely Shoulder Flexion Joint, Shoulder abduction Joint, Humeral rotation joint and Elbow Flexion Joint) motion are synchronized. The master robot arm is controlled by a sliding mode controller and the slave robot arm is synchronized using a basic PD plus adaptive control, employing the position and velocity errors between the master and the slave. During the operation, if a joint of the slave robot arm saturates or malfunctions (for instance, Elbow flexion joint does not respond or free swinging), consequently, slave robot arm will go into chaos (i.e., chaotic motion of the end effector). In this case, a chaos controller kicks in to recover and re-synchronize the motion of the slave robot arm end effector. This re-synchronization is extremely important to complete the task in hand to address any safety issues arising from any joint malfunction of the slave robot. Effectiveness of the scheme is tested in simulation using Bristol Robotics Laboratory Humanoid BERT II arms.
Constructing the Ecological Security Pattern for Sponge City: A Case Study in Zhengzhou, China
Authors: Dong Rencai , Zhang Xueqi , Li Huanhuan
Published: February 2019

Waterlogging is becoming a severe and universal phenomenon in China, so the construction of sponge cities is proposed to address urban water problems abiding by the overall principles of ecological priority and low-impact development. The ecological security pattern (ESP) is an effective way to balance rapid urbanization and ecological protection. Taking Zhengzhou as an example, this study, performed a geographic information system (GIS) modeling, which constructed a targeted ESP for the construction of a sponge city based on comprehensive analysis of multi-factor water ecological sensitivity. Compared to previous studies of ESP, some improvements were made in the identification method of ecological sources, corridors, and nodes. By analyzing the ESP, the study divided the whole city into different construction zone. Through different protection and planning strategies for these areas, the integration and connectivity of the ecological sources can be improved, and thus, urban ecological security can be improved. The ESP for sponge city is a relatively more systematic and scientific way to guide the construction of a sponge city, and can be used for reference to other cities in the process of sponge city construction.
Total Internal Reflection of Deep-Ultraviolet Light in a Water Waveguide and Its Application to Water Disinfection Technologies
Authors: Matsumoto Takahiro , Kikojima Rika , Fukuoka Tomomi , Tatsuno Ichiro , Hasegawa Tadao
Published: February 2019

We propose a new disinfection technology based on a novel concept involving the use of a small, deep-ultraviolet light-emitting diode (DUV-LED); the 265-nm DUV light is coupled to a running-water stream and is guided to a distant position without diffusion due to the total internal reflection of the DUV light inside the water stream. We demonstrate here the effect of the water waveguide disinfection technique by showing significant inactivation of a contaminated surface with indicator bacteria; this was verified by comparing the results of three disinfection methods: (i) disinfection with DUV light, (ii) disinfection with running water, and (iii) disinfection with the water-waveguide method. We believe that the marriage of the point-source nature of DUV-LED emission and the water-waveguide effect paves the way towards new applications such as water washing technologies that can reduce water consumption more than one order of magnitude without using additional chemicals in a simple manner.
Improving control of carbide-derived carbon microstructure by immobilization of a transition-metal catalyst within the shell of carbide/carbon core–shell structures
Authors: Ariyanto Teguh , Glaesel Jan , Kern Andreas , Zhang Gui-Rong , Etzold Bastian J M
Published: February 2019

Carbon materials for electrical energy devices, such as battery electrodes or fuel-cell catalysts, require the combination of the contradicting properties of graphitic microstructure and porosity. The usage of graphitization catalysts during the synthesis of carbide-derived carbon materials results in materials that combine the required properties, but controlling the microstructure during synthesis remains a challenge. In this work, the controllability of the synthesis route is enhanced by immobilizing the transition-metal graphitization catalyst on a porous carbon shell covering the carbide precursor prior to conversion of the carbide core to carbon. The catalyst loading was varied and the influence on the final material properties was characterized by using physisorption analysis with nitrogen as well as carbon dioxide, X-ray diffraction, temperature-programmed oxidation (TPO), Raman spectroscopy, SEM and TEM. The results showed that this improved route allows one to greatly vary the crystallinity and pore structure of the resulting carbide-derived carbon materials. In this sense, the content of graphitic carbon could be varied from 10–90 wt % as estimated from TPO measurements and resulting in a specific surface area ranging from 1500 to 300 m2·g−1.
METHOD FOR FORECASTING THE TIME STANDARD OF MULTI‐CHARACTERISTIC ITEM
Authors: Hadad Yossi , Friedman Lea
Published: February 2019

The purpose of this paper is to propose a method for determining the time standard of items based on several characters, where part of them is quantitative and some of them are qualitative (dichotomic). The method of determining the time standard of an item is based on Multiple Linear Regression where the dependent variable is the time standard for the production of a lot size of item and the characters of the item are the independent or regressor variables. In this paper we introduce the method for determining the time standard of an item, the way for measuring the qualitative independent variable. The method is illustrated on a case study in an Israeli plant in its research department of materials and processes. In this department a great variety of items were produced, each item has different characters.
AGREEMENT OF EXPERT ESTIMATES
Authors: Podvezko Valentinas
Published: February 2019

The application of multicriteria methods largely depends on the calculation of the criteria weights based on expert evaluation. The results obtained can be used for practical purposes if expert judgments are in good agreement. This may be determined by the concordance of a coefficient obtained by ranking the available alternatives. The paper considers a possibility to apply the concordance coefficient in cases when expert evaluation is not based on ranking. The calculations reveal the dependence of the agreement of expert estimates on a particular method used. The highest degree of agreement has been obtained by using the direct ranking method. The effect of equally assessed criteria, i. e. the tied ranks on the concordance coefficient and thereby on the level of expert judgments agreement is usually insignificant and cannot change the results of rating.
EVALUATION OF CONTRACTORS BY USING COPRAS - THE MULTIPLE CRITERIA METHOD
Authors: Andruškevičius Algirdas
Published: February 2019

Some methods allowing for the selection of the most suitable contractor based on 26 criteria are offered. The bidding procedures of FIDIC, the international organization of consulting engineers are assessed. Contractors are evaluated by a multicriteria decision method COPRAS. The significance of the contractor evaluation criteria is determined by ranking. A description of the criteria and their rankings according to 100‐point scale are provided. A case study of selecting the contractor for the construction of a trade and entertainment centre out often bidders is also described.
THE SELECTION OF RATIONAL CONSTRUCTIONAL TECHNOLOGY PROCESSES VARIANTS USING COPRAS METHOD
Authors: Malinauskas Pranas , Kalibatas Darius
Published: February 2019

The article analyses the manner of selection an optimal building technological project which would pander the majority of the concerned members (architects, customers, designers, contractors and so on) interests. Assessment technique is being considered and its features as well. The need to value the expenses associated not only with the construction period, but also with the exploitation period is explaned. A few examples are given about choosing a rational project considering not only the cost, but also some value factors that influence job quality or exploitation.
VERBAL ANALYSIS OF ENGINEERING AND CONSTRUCTIONAL SOLUTIONS
Authors: Ustinovičius Leonas , Andruškevičius Algirdas , Kutut Vladislavas , Balcevič Robert , Barvidas Arūnas
Published: February 2019

The construction contracts which meet the interests of all the sides involved are the core element of every successful constructural project. That is why the advise of how to sign the accurate and effective contract has growing importance. International construction contractors are often faced with the situation of working in unfamiliar construction environment. One potential source of risk is the contractual requirements embodied in the general conditions of contracts. Authors aim to analize construction contracts being used and to define their effectiveness using the method of verbal analysis.
SHAPE DETERMINING OF A LOADED CABLE VIA TOTAL DISPLACEMENTS
Authors: Juozapaitis Algirdas , Norkus Arnoldas
Published: February 2019

Cable structures are very efficient (in economic aspect) when applied to cover large spans. The cable structure consists of a single cable or a network of cables. The cable attractive feature is the highest ratio of strength to weight amongst other carrying structural elements, usually applied in engineering practice. But a cable is a specific structural element able to response only one type of deforming ‐ tension (flexural rigidity actually vanishes). Therefore, when loaded a cable shapes the form to resist tension only. This adaptation is followed by large nonlinear displacements. Thus, the nature of geometrical nonlinear cable behavior is quitie a different from that of rigid structural elements. Both elements response via small deformations when loaded, but large displacements of a cable are conditioned by its adaptation to loading, and those of rigid structural elements ‐ by actual deformations. One can also note that deformations of a cable are significantly less than those of rigid structural elements, but at the same time actual cable displacements are significantly larger. Thus, the main disadvantage of a cable structure is its response to loading by large displacements caused by asymmetric loading component (usually met in engineering practice, e.g. the design of suspension bridges, coverings of stadium, etc). Therefore stiffness conditions predominate in the actual codified cable design. Having identified governing factors conditioning displacement magnitudes one can introduce the constructional means/solutions assigned to reduce them if required. Therefore the evaluation of cable displacements by a reliable and sufficiently exact method compatible with the calculation of actual engineering structures is under current necessity. When analyzing total displacements the principle of superposition is employed in a special sequence. Total displacement is split into two components: kinematic and elastic. The first component represents cable form shaping the loading, the second one is conditioned by elastic deformations. Any point displacement of an asymmetrically loaded cable can be expressed via its middle span. The developed analytical expressions to evaluate middle span displacements are presented. They enable to identify maximal displacements and their locations. The developed analytical method for total displacements evaluation is tested numerically. The comparative analysis in respect of the influence of various parameters conditioning displacement magnitudes is performed. The displacement evaluation errors, their causality conditioned by the application of approximate‐ widely applied engineering methods, are discussed.
FINANCIAL DEVELOPMENT AND ECONOMIC GROWTH IN POLAND 1990-2018
Authors: Škare Marinko , Sinković Dean , Porada-Rochoń Małgorzata
Published: February 2019

The aim of the paper is to study finance-economic growth nexus in Poland using a time series approach. We find evidence of the existence of the finance-economic growth link in Poland. Most empirical studies do not consider the lending structure of the financial sector (share of households’ vs firms in total credits). The obtained results show that when using the share of households and companies in total credits, the long run empirical relationship in VECM is statistically significant and larger. Empirical studies using total private credit share in the GDP or the value/volume of total credits tend to undervalue the impact of financial development on economic growth. In the case of Poland, empirical evidence that supports this hypothesis was found, and therefore policymakers and researchers should take bank lending structure into account. Furthermore, the study shows that financial series may possibly have long memory properties and that researching the financial development-growth nexus could require using fractional integration methods. The reported evidence suggests financial development plays a significant role in both economic growth and credit growth. Due to data limitation, this study focuses on a single country case – Poland with the need for further research (larger sample).
Using Hα Filaments to Probe Active Galactic Nuclei Feedback in Galaxy Clusters
Authors: Qiu 邱 Yu 宇 , Bogdanović Tamara , Li Yuan , McDonald Michael
Published: February 2019

Recent observations of giant ellipticals and brightest cluster galaxies (BCGs) provide tentative evidence for a correlation between the luminosity of the Hα-emitting gas filaments and the strength of feedback associated with the active galactic nucleus (AGN). Motivated by this, we use 3D radiation-hydrodynamic simulations with the code Enzo to examine and quantify the relationship between the observable properties of the Hα filaments and the kinetic and radiative feedback from supermassive black holes in BCGs. We find that the spatial extent and total mass of the filaments show positive correlations with AGN feedback power and can therefore be used as probes of the AGN activity. We also examine the relationship between the AGN feedback power and velocity dispersion of the Hα filaments and find that the kinetic luminosity shows a statistically significant correlation with the component of the velocity dispersion along the jet axis, but not the components perpendicular to it.
Young adults’ interaction with online news and advertising
Authors: Martínez-Costa María-del-Pilar , Serrano-Puche Javier , Portilla Idoia , Sánchez-Blanco Cristina
Published: February 2019

This research aims to portray the way young adult people interact with news and how their consumption is affected by advertising and personal data sharing. 'Digital News Report Spain 2018', a questionnaire on the consumption of digital media undertaken by a national panel of 2,023 Internet users, is used as a main source. Among the users mentioned, there were 293 young people from 25 to 34 years old who belong to the Millennial generation. Data from this report was completed with a qualitative study in which two focus groups were held, featuring people of that age frame residing in Navarre. The paper concludes that young adult people are generally interested in news, which they access mainly via mobile devices. Their interest grows when the content affects them directly, but also if they empathize with the topic. On the other hand, their familiar background and social routines shape the way they receive information. Young adult people still make use of traditional media, although they consider it ideologically biased. Advertising is something annoying, although they generally have little knowledge and even less intention to use ad-blockers. Finally, their review of the personalized services is negative, but they tend to give away personal data to media if this facilitates their news access.

Esta investigación tiene como objetivo caracterizar cómo interactúan los jóvenes adultos con las noticias, en qué medida su consumo se ve condicionado por la presencia de publicidad y si se preocupan por la cesión de datos personales. Para ello, se toma como punto de partida el «Digital News Report Spain 2018», informe elaborado a partir de un cuestionario sobre consumo de medios digitales a un panel nacional de 2.023 internautas; de ellos, 293 son jóvenes de 25-34 años, que pertenecen a la generación «millennials». Estos datos se completaron con un estudio cualitativo, realizando dos grupos de discusión con personas de esa franja de edad residentes en la Comunidad Foral de Navarra. Entre las conclusiones de la investigación se señala que los jóvenes adultos se interesan por las noticias, a las que acceden de manera prioritaria por dispositivos móviles. Este interés es mayor cuando el contenido les afecta directamente o si empatizan con la temática de la noticia. Por otra parte, el entorno familiar y las rutinas sociales condicionan su manera de informarse. Siguen accediendo a medios tradicionales, aunque los consideran ideologizados. La publicidad la perciben como molesta, si bien no hay conocimiento ni un uso generalizado de bloqueadores. Finalmente, valoran negativamente los servicios de personalización actuales, aunque ceden algunos datos personales a los medios si le facilita el acceso a la información.
Reading and informal learning trends on YouTube: The booktuber
Authors: Vizcaíno-Verdú Arantxa , Contreras-Pulido Paloma , Guzmán-Franco María-Dolores
Published: February 2019

The digital era has perpetuated new pedagogies of collective participation in networks that requires reflection in the conventional education area, because of YouTube, as audiovisual platform of outstanding international recognition, concentrates an extensive repertoire of informal learning practices among young people. In this case, the research focuses on a form of literary expression driven by the new Booktube community, which is dedicated to the recommendation of books and the promotion of reading by focusing their messages through the videoblog format. This aspect, closely popularized in the platform, allow us to deepen new youth practices outside classroom that refer to the promotion of books and critical and judicious expression on aspects related to content, formats, genres and authors in a context supported by the media ecology. In order to deepen the reasons why youth reads currently, we developed a literature review starting with the transmedia literacy concept evaluating narrative and aesthetic competences and applying a content analysis and a case study that collects channels of two Spanish booktubers with high impact and community: Javier Ruescas and Fly like a Butterfly. Results discern an affinity space linked to the opinion of peers that promotes reading and writing, and the ability to interpret, describe, compare and reflect about the literary context.

La era digital ha perpetuado nuevas pedagogías de participación colectiva en red que requieren una reflexión en el área educativa, en tanto que YouTube, como plataforma audiovisual de sobresaliente reconocimiento, concentra un extenso repertorio de prácticas de aprendizaje informal y juvenil. En este caso, la investigación se centra en una forma de expresión literaria impulsada por la comunidad Booktube, que se dedica a la recomendación de libros y al fomento de la lectura focalizando sus mensajes a través del formato videoblog. Dicha vertiente, estrechamente popularizada en la plataforma, nos permite profundizar en nuevas prácticas juveniles fuera del aula que remiten a la promoción de libros y a la expresión crítica y juiciosa sobre aspectos relacionados con el contenido, los formatos, los géneros y los autores en un contexto auspiciado por la ecología mediática. Con el objetivo de profundizar en los motivos por los que la juventud lee actualmente, desarrollamos una revisión bibliográfica a partir del alfabetismo transmedia evaluando las competencias narrativas y estéticas, y aplicamos un análisis de contenidos mediante un estudio de caso que recoge los canales de dos booktubers españoles con amplia repercusión y comunidad: Javier Ruescas y Fly like a Butterfly. Los resultados atisban un espacio de afinidad ligado a la opinión entre pares que promueve la lectura y escritura, y a la capacidad para interpretar, describir, comparar y reflexionar sobre el contexto literario.
Les multiples facettes de l’entrepreneuriat scientifique de James Lovelock dans les années 1960-70 : développement d’instruments, consultance sur les pollutions et hypothèse Gaïa
Authors: Briday Régis , Dutreuil Sébastien
Published: February 2019

Chimiste célèbre pour avoir élaboré l’hypothèse Gaïa, James Lovelock (1919-…) se présente comme un « scientifique indépendant » installé dans son laboratoire-maison, retiré dans la campagne anglaise. À rebours de ce récit, les auteurs décrivent son parcours dans les années 1960-70 comme celui d’un « scientifique entrepreneur ». Après vingt ans comme ingénieur-fonctionnaire dans le domaine biomédical, Lovelock délaisse cette position pour s’établir à son compte. Son expertise dans le domaine de la chromatographie et l’invention d’instruments font de lui un consultant courtisé, aussi bien par de grandes entreprises chimiques et pétrolières que par de prestigieuses institutions scientifiques publiques. De grandes synergies, mais aussi des tensions, s’opèrent entre ses activités d’expert sur des questions environnementales, de consultant pour des entreprises et de théoricien élaborant une nouvelle conception de la Terre et de la vie. Lovelock ne doit plus uniquement être regardé comme l’un des pères des sciences du système Terre et un acteur important des mutations culturelles autour de l’environnement depuis les années 1960, mais également comme une incarnation précoce de scientifique entrepreneur avec un pied dans la recherche publique sur l’environnement et l’autre dans la recherche industrielle. Classification JEL : L26, O31, I23
La crise identitaire du Parti démocrate face à l’avènement de l’aristocratie blanche
Authors: Richomme Olivier
Published: February 2019

Le capitalisme financier américain et les mécanismes d’accumulation de richesse sur plusieurs générations ont crée une nouvelle forme d’aristocratie qui est presque exclusivement blanche. Cette stratification ethno-raciale, et sa mesure statistique, change la perspective que les Américains ont des inégalités. Cet article propose dans un premier temps d’examiner dans quelle mesure affiliation ethno-raciale et appartenance à une classe sociale sont imbriquées. Dans un second temps, nous exposons le dilemme stratégique du Parti démocrate en réponse à l’avènement de cette aristocratie blanche. Le parti, fortement divisé quant aux leçons à tirer de l’élection de 2016, se trouve poussé, presque malgré lui, vers une certaine forme d’intersectionalité par des contraintes électorales fortes.
Obama et le Affordable Care Act : un nouveau discours pour une nouvelle approche politique
Authors: Stephan Lea
Published: February 2019

Cet article propose une analyse du discours de Barack Obama concernant la politique de santé et les politiques sociales. L’analyse met en avant une nouvelle approche discursive centrée sur l’union par intérêt économique des différentes populations raciales des classes moyenne et ouvrière en puisant dans une rhétorique de transcendance raciale et de populisme économique. Le discours d’Obama est une réponse méticuleuse au discours conservateur et néolibéral (qui favorise la division raciale et le désengagement de l’État) afin de créer un nouvel environnement discursif favorable à la réforme de santé. Il est ensuite montré comment l’approche idéologique d’Obama se reflète dans le Affordable Care Act .