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This paper synthesises a recent research that includes opinion dynamics models and experiments suggested by the model results. The mathematical analysis establishes that the model's emergent behaviours derives from cognitive biases that should appear in quite general conditions. Moreover, it seems that psychologists have not yet detected these biases. The experimental side of the research therefore includes specifically designed experiments that detect these biases in human subjects. The paper discusses the role of the model in this case, which is revealing phenomena that are almost impossible to observe without its simulations. [ABSTRACT FROM AUTHOR]

The development of the relay protection based on open architecture is a relevant direction of electrical and electronic engineering. The paper presents the problem of the modern microprocessor-based relay protection that consists in the impossibility of the element replacement with alternatives from other manufacturers. The literature review on the reed switches application for relay protection, traditional and open-source solutions are given. Τhe structural scheme of the processes and relay protection device with different modules and the use of open-source communication and Industrial Internet of Things is demonstrated. The goal of the further research of sensibility, selectivity and reliability is set. [ABSTRACT FROM AUTHOR]

The objective of this paper is to obtain an excellent structure of a rotational hydrodynamic cavitation reactor (RHCR) by a numerical method and then to investigate the cavitating flow characteristics of the optimized RHCR experimentally. The RNG k-ε turbulence model combined with the Zwart cavitation model was applied to analyze the influence of the straight blade number, the baffle position and the baffle shape on the pressure field, bubble distribution and turbulence kinetic energy of the RHCR. The results show that compared to the original model, an RHCR with a straight blade number of 6, a baffle position of 0.74 and a triangular baffle offers better cavitation performance. Moreover, the energy performance and the cavitation development process of the optimized RHCR were studied experimentally. The results indicate that the multiscale bubbles are induced by straight blades and baffles of the optimized RHCR, accompanied by the twice quasi-periodic shedding dynamics in one cycle. The findings of this study have positive significance for the design and optimization of RHCRs. [ABSTRACT FROM AUTHOR]

Debates about the planet’s recent entrance into an epoch of earth history now characterized by the destructive effects of humankind’s having become a planetary force to rival plate tectonics, super volcanos and asteroid impacts should have the effect of placing Theodor W. Adorno and Walter Benjamin’s conception of natural history in a new light. For what it is perhaps most striking about this conception is not only its proximity to a present made newly aware of nature and history’s total interpenetration, but just how precisely its understanding of natural history’s essential transitoriness accords with what is now everywhere observable: that ever-accelerating process of disintegration through which it becomes clear that the life of phenomena can only be known today if also understood in terms of that reality of disappearance to which the current age daily testifies. For Adorno and Benjamin, such a conception of natural history had very real consequences for how philosophical cognition and construction would have to be remade, leading both to pursue far-reaching experiments in intellectual production that it is the task of this paper to reconstruct in the light of its possible relevance for the theory and practice of critical theory today. To draw out the stakes of these experiments will first require a reconsideration of current efforts at contending with some of the most practical problems of our own present. Setting out from Alexander Kluge’s demonstration that the kind of “learning processes” necessary for effective resistance often fail because they are simply far slower than the combined force and velocity achieved by prevailing systems of domination, exploitation and extraction, this paper will then ask how a critical theory informed by natural history might today confront the contemporary problem of tactics and strategies at a time when the forces of organized destruction have themselves changed so dramatically. For now that older, more traditional systems of coercion have long since given way to a novel system of overwhelming planetary exploitation, extraction and extermination, it is necessary to ask again how such transformations in the forms of organized violence might be met by corresponding transformations in the theory and practice of critical theory in this new time of extinction. In response, this paper will seek to reconstruct the history of debates in critical theory about theory and praxis, tactics and strategies in the light of more recent discussions about how to combat a system whose result is the continuing and exponential increase in destruction brought about by global warming. The paper will then conclude by setting Adorno and Benjamin’s conception of natural history in relation to more systematic conceptions of contemporary society by turning to those writers, like Wolfgang Streeck and Andreas Malm, who have recently begun to consider how the many contradictions and forces of destruction inbuilt to present-day society may well require a fundamental reconsideration of the contemporary status of various inherited forms of political resistance. [ABSTRACT FROM AUTHOR]

Copyright of Caderno Brasileiro de Ensino de Física is the property of Caderno Brasileiro de Ensino de Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Interest in firearms has been increasing recently, and it is, therefore, necessary to deal with the possible firearms injuries that these weapons can cause. Gunshot wounds depend on the wounding potential which firearms can cause. The wounding potential is commonly tested on the replacement material. In this paper, an experimental measurement is used. The first measurement is based on the post-firing products left on the paper, and the second one is based on the depth of the shot of two types of pellets fired from the airgun. To prove or disprove the ability of the wounding potential of the investigated weapons, it is then necessary to determine the possible degree of injury caused to the soft tissue of the human body. The results are essential for further investigation and future research of gunshot wounds caused by tested weapons. [ABSTRACT FROM AUTHOR]

This paper examines the effect of an intensive counseling program to promote college access of students who are eligible for college. Using data from an experimental panel study, we examine the average effect on university enrollment directly after high school graduation and the effect heterogeneity by educational background. No positive effect of participation is found. We discuss these results in relation to the potential of reducing inequalities by individual counseling in Germany. [ABSTRACT FROM AUTHOR]

Digital forensics (DF) is becoming one of the most prestigious research areas in computer science due to its inherent nature of providing a means to acquire, examine, analyze, and report evidence to be used in legal processes. To successfully perform it, novel techniques, approaches, and tools have been proposed, experimented on, and evaluated by researchers. However, the experimentation process is not a trivial task in this area as substantial evidence is not accepted in court. Therefore, the experimentation process has to be improved in DF, especially its documentation and data sharing to enable its reproducibility. The objective of this paper is to characterize the stateof- the-art research on DF experiments. We conducted a Systematic Mapping Study (SMS), analyzing 107 primary studies reporting DF experiments. We demonstrate that DF experimentation somehow fails at documenting the most essential elements of an experiment, such as hypothesis, variables, design, instrumentation, validity evaluation, setup, training, datasets and benchmarks, statistical techniques (descriptive, hypothesis, and effect-size test), limitations, and data sharing. In this work, we also propose a set of recommendations to improve experimentation in DF, especially regarding its replication and reproducibility. DF experimentation should evolve if the community intends to provide reliable and reproducible studies. By embracing this, both academicians and practitioners might benefit from such experiments and evidence. [ABSTRACT FROM AUTHOR]

• The rock failure volume model under particle jet impact is put forward and established. • Damage evolution and failure volume under particle jet impact are dynamically simulated and analyzed. • The correctness and applicability of mathematical model were verified by comparative analysis with experiment and simulation. There are some difficult problems in deep and ultra-deep oil and natural gas drilling process due to the complex stress environment and hard formation, such as slow drilling speed, well deviation and high cost. As one of the important parameters to measure rock-breaking efficiency, mathematical model of failure volume is proposed in this paper, which is suitable for deep-well rock-breaking technology. First, the particle jet impact rock-breaking laboratory experiment was conducted based on the self-developed experimental platform, and the strength of rock specimen was tested. Then, the failure volume model of particle jet impact rock-breaking which varied with particle size, and water-jet velocity was established based on contact mechanics. Meanwhile, the simulation model and method of particle jet impact rock was carried out and introduced, and damage evolution was dynamical simulated. Comparative analysis of experiment results, model calculation and dynamic simulation was used to analyze the failure volume, and it showed, failure volume would increase linearly with increase of water-jet velocity, while particle size has little effect on failure volume under the condition of constant nozzle diameter. The comparison results of theoretical modeling and rock-breaking experiment are basically consistent, which proves the correctness and applicability of failure volume model. [ABSTRACT FROM AUTHOR]

The paper deals with spectators induced vibration on a grandstand and monitoring of fans behavior during ice hockey games. The previous experiments focused on the football spectators behavior and grandstand vibrations were carried out at the AC Sparta football stadium in Prague in 2013 and in 2015 [1–3] . The followed experiments described in the paper continued on above mentioned ones. The topic is the same, only fans are different – ice hockey fans. The experiments were realized at the ice hockey stadium in Pilsen and compared the behavior of spectators during two matches of the same two teams but in different phases of the competition – the regular season and playoffs. The experiment was focused on the part of the stadium where the most active fans of the home team are usually concentrated. The observed grandstand vibrations were substantially smaller than at the football stadium. It was caused partially by the different grandstand structural systems and also by the dissimilar behavior of football and ice hockey spectators. [ABSTRACT FROM AUTHOR]

This paper presents the results of an experiment, conducted on a sample of computer science students, using the adaptive learning system called ALS_CORR[LP]1. Indeed, unlike the traditional LMS, adaptive learning systems provide a personalized learning experience based on specific objectives, prerequisites and learning styles, generating thereby a specific learning path. However, the main issue resides in the fact that they assume that the generated learning path is supposedly the leading one, which is far from being true, as we can always detect some failure cases during the evaluation phase. In this paper we will conduct a learning experiment using the system ALS_CORR[LP], which has the ability to correct the generated learning path by recommending the most relevant learning objects, and update the learner model based on a calculation of similarity in behavior between the struggling learner and the succeeding ones. We will later analyze the results of behavior tracking within the system. [ABSTRACT FROM AUTHOR]

Sandwich panels, usually used as members of wall or roof cladding, can provide lateral and torsional restraint to metal members of the substructure along their spans. They can positively influence the buckling resistance of the metal members. Lateral restraint given by sandwich panels can be considered for downward as well as uplift load applied on the surface of the panels. Torsional restraint can normally be utilized in case of downward load only. The uplift load causes the reduction of the contact area between the panels and metal members which is assumed to result in small (or conservatively zero) values of rotational stiffness which corresponds to the torsional restraint. There is a lack of data regarding torsional restraint under uplift load. Certain values of torsional stiffness can be considered when metal members of cold-formed cross-sections are utilized. The paper focuses on experimental verification of torsional restraint given to steel purlins of thin-walled cold-formed cross-sections by sandwich panels under uplift load. As the test setup for verification of the torsional restraint provided to metal members by planar members according to the actual standard for design of steel structures does not cover the influence of external load applied on the surface of the panels, a special test setup taking the external load into account had to be used. The paper describes the specimens, the test setup and the procedure of testing and summarizes selected relevant results of the series of performed tests. [ABSTRACT FROM AUTHOR]

The analysis of machine tools shows that, despite sufficient cooling capacity, thermo-elastic deformation is insufficiently compensated because component dependent heat losses and heat dissipation are poorly coordinated in time and location. This leads to impairments of machine performance and production quality. The paper summarizes experimental and simulative investigations on cooling in machine tools. At component level, convection in the channel is modelled to derive measures for effective cooling. Moreover, thermo-energetic properties of a machining center are measured. This is used to develop a thermo-hydraulic network model for cooling and to investigate various measures for structure and control optimization. Finally, these results are validated on test-rigs. [ABSTRACT FROM AUTHOR]

The simulation and process research on additive manufacturing nickel three-dimensional microstructure by maskless localized electrodeposition with cone-shaped micro anode and micro fluidic electrolyte were carried out in this paper. The boundary conditions were set according to the process parameters of the maskless localized electrodeposition, the micro electrodepositing area was numerically simulated by using COMSOL Multiphysics software to analyze the influence of flow field distribution and electric field distribution on actual processing, the simulation results show that the factors affecting localized electrodeposition are as follow: Among the three factors, the interelectrode voltage has the greatest effect on the process, the duty cycle has the smallest effect, and the effect of the interelectrode gap is moderate. The CAD modelling and slice processing of 3D microstructure, and the movement path optimizing of electrode were completed with reference to the additive manufacturing method. The effects of main process parameters such as interelectrode voltage, pulse duty cycle and interelectrode gap on experimental results were studied by controlling single variable method and orthogonal experiment method. Study results demonstrate: Electrode shape, interelectrode voltage, pulse current duty cycle and interelectrode gap have different effects on microdeposition rate, surface morphology of microstructure and consistency of deposition rate. The optimized process parameters after orthogonal experiments are as follow: Interelectrode voltage(4V), pulse duty cycle(0.4), interelectrode gap(5μm), pulse frequency(10KHz), the movement speed of coordinate table's X and Y axis are both 1μm/s, and Z axis is 5μm/s. The better electrodepositing results have been obtained: the electrodepositing rate may reach 460μm3/s and the simple nickel microstructure (nickel cylinder) has a maximum aspect ratio of 7:1. [ABSTRACT FROM AUTHOR]

This paper presents calculation model enabling determination of the leakage rate in labyrinth seals. Described model is based on the Saint-Venant equation. It includes a new type of flow coefficient, which was determined based on experimental tests and described depending on the Reynolds number and the radial clearance. The structure of this calculation model can be applied to determine the leakage rate in straight through, staggered labyrinth seals as well as with various number of clearances. This model enables determining distribution of thermodynamic and flow parameters of the gas along the seal length. Results obtained from this model were next compared with experimental data for various types of seals. It enabled determination of kinetic energy carry-over coefficient in geometries under investigation. The value of this coefficient was then compared with the value of the coefficient from the Scharrer's, Neumann's and Hodkinson's models. Obtained results indicate that the value of the kinetic energy carry-over coefficient depends not only on the seal geometry, but also on the pressure decrease. [ABSTRACT FROM AUTHOR]

In many areas of research/ production, a lot of factors are combined to obtain a desired product. To be able to analyze which factors (or combinations of factors and at what level) are significant, the experiment has to be replicated. For economic or practical reasons, it may not be feasible to perform the experiment more than once therefore unreplicated factorial designs are often employed. This is especially true in the field of Medicine, Pharmacy and Industrial production units. The traditional method of analysis of variance (ANOVA) cannot be employed in unreplicated factorial designs, therefore many methods have been proposed in literature. In this paper, a new method of analyzing unreplicated factorial designs is proposed and was compared with some of the existing methods. The four existing methods considered were: Lenth, Berk and Picard, Juan and Pena, and Dong. The comparison was performed using Monte Carlo simulation method. The criteria used in evaluating the performances of the methods are Power and Individual Error Rate (IER). Using these criteria of evaluation, the results showed that on overall performance, Dong method is the best among the four existing methods considered and was closely followed by Berk and Picard, Lenth, then Juan and Pena methods in that order. It was also found that not only is the proposed method simpler to compute, it competed favourably with Dong and even performed better than all the others when IER is used for assessment. [ABSTRACT FROM AUTHOR]

The structure, cooling principle and operation characteristics of transformer split type cooling system was different from conventional cooling systems. Such as the research work of simulation test equipment in the field was few, causing a lack of scientific basis for the equivalence of simulation test, and parameters set of split type cooling system without scientific and professional analysis. The result is that so many features and operation characteristics were not fully grasped before. Therefore, it was necessary to carry out the corresponding research work. The experimental study was carried out in this paper. This paper would research the simulation test method of split cooling system based on a 10kV distribution transformer. The test device can realize the flexible regulation for the vertical and horizontal position. According to the temperature-rise test method of transformers, performance test of split type cooling system was carried out based on the change of oil flow or radiator location. Finally, the research results of different pipe diameter, height and horizontal distribution were proposed. The study would provide more references for operation instruction of large power transformer's split type cooling devices. [ABSTRACT FROM AUTHOR]

The authors of this paper have developed and tested a novel modular power unit with the variable drawbar pull category 1.4-3 (1.4-3 tf) (drawbar pull based classification approach is used in Ukraine and some other countries) under the mark MPU-80. In this paper the proposed results of experimental, field and laboratory research of the ploughing unit based on this power unit are listed. [ABSTRACT FROM AUTHOR]

Composite structural elements can serve dual purposes of transferring the load and insulating the buildings. This paper presents and discusses the results of experimental study carried out to understand the flexural behavior of prototype precast insulated concrete sandwich panels using truss-shaped continuous shear connectors. Experimental study consisted of four prototype concrete sandwich panels tested under four-point bending simulating one-way slab action. Panel thickness and size of wire mesh used as reinforcement in concrete wythes are the major parameters considered. Test results indicate that the truss-shaped shear connectors are effective to achieve composite action of the panels until failure. Test results also indicate that the panel thickness affects the flexural load carrying capacity, and size of wire mesh affects the ductility. Experimental and analytical studies are required in this area towards developing guidelines for design of concrete sandwich panels for field applications. [ABSTRACT FROM AUTHOR]

Proton Exchange Membrane fuel cells (PEMFC) has emerged as the most widely-used type among fuel cells, due to various advantages. Bipolar plates play a major role in the performance of PEMFC. Flow fields in the bipolar plates distribute fuel and oxidant over the reactive sites of the membrane electrode assembly. Bipolar plates are typically graphite with parallel or serpentine channels as flow fields. Graphite is heavy and has fabrication inaccuracy; it is also costly and brittle. In this paper, open-cell aluminium foam is experimentally investigated as a flow field for a new bipolar plate design made from solid aluminium. The performance of the conventional bipolar plate/flow field was directly compared to that of the aluminium-foam novel design at the same operational conditions. Results show that the cell current, voltage and power density were improved. As importantly, the conversion efficiency was higher for the aluminium-foam design, and the fuel consumption was reduced. [ABSTRACT FROM AUTHOR]

Precast concrete sandwich panels can serve dual purposes of transferring loads and insulating the structure. A survey of the literature indicates that feasibility studies on the use of precast concrete sandwich panels to resist punching load are not reported. This paper presents the results and discussions of experimental and analytical studies conducted on two prototype precast concrete sandwich panels to determine and compare the behavior of precast concrete sandwich panels under punching and bending loads. The precast concrete sandwich panels consisted of top and bottom reinforced concrete wythes connected using continuous truss-type shear connectors and expanded polystyrene as the core. During the experiments, load-deflection curves and strains in concrete surfaces and wire mesh and reinforcing bars were monitored until panel failure. Test results indicate that the type of flexural loading conditions has a significant effect on the flexural behavior of these types of sandwich panels, in particular the failure mode, after a specific applied load magnitude and bending moment. Analytical studies indicate that the ultimate flexural load capacity predicted using the ACI 318-11 strength equation is comparable to that of experimental ultimate flexural load of the panel subjected to punching. Further studies are required in this area, in particular, developing design guidelines to use these panels as floor panels in housing systems. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the thermal performance of serpentine pipe flat plate collectors with different pipe diameters and pipe spacings was tested by experiments. On this basis, two phase change materials with high melting point (70 °C) and low melting point (15 °C) were laid on the upper and lower parts of the pipeline to enhance the frost resistance and high temperature resistance of the collector. The experimental results show that under strong solar radiation conditions, high-melting phase change materials can absorb a lot of heat when the water temperature of the collector is high, thereby slowing down the water temperature rise and avoiding overheating, and when the collector is cooled, phase change can be effectively utilized to slows down the rate of temperature drop of the collector, so as to achieve reasonable utilization of the overheating of the collector; in the low temperature environment, the low melting point phase change material can significantly reduce the cooling of the collector and improve the frost resistance of the collector. The placement of the two kinds of different melting point phase change materials was investigated, and the results show that the low-melting phase change material under the pipe is more conducive to the collector antifreezing. However, for the hot regions, the high-melting phase change material placed at the top of the pipe is more conducive to preventing overheating. [ABSTRACT FROM AUTHOR]

This paper deals with the analysis of the shear strength of reinforced concrete elements, with loads on the upper side near edge of the support. The reinforced concrete elements are designed according to EN 1992-1-1:2004. Results of the calculated shear strength are compared with the results of the experimental research of the reinforced concrete beams that were made of high-strength concrete and normal-strength concrete, comparatively. Analysis is related to the beams for which ratio between shear span (a v ), measured from the inner edge of the support, and effective depth of the cross-section (d), is smaller than 2.0. In that case, for design of the shear strength according to EN 1992-1-1:2004, provision that shear force should be reduced by the coefficient β=a v /2d is prescribed. Results of the experimental research, in correlation with shear strength calculated according to EN 1992-1-1:2004, are being analyzed in this paper. It has been established that the proposed reduction gives a significantly reduced magnitude of the design value of the load, which do not provide the necessary safety of calculation. [ABSTRACT FROM AUTHOR]

This paper deals with the analysis of the shear strength of reinforced concrete elements, with loads on the upper side near edge of the support. The reinforced concrete elements are designed according to EN 1992-1-1:2004. Results of the calculated shear strength are compared with the results of the experimental research of the reinforced concrete beams that were made of highstrength concrete and normal-strength concrete, comparatively. Analysis is related to the beams for which ratio between shear span (av), measured from the inner edge of the support, and effective depth of the cross-section (d), is smaller than 2.0. In that case, for design of the shear strength according to EN 1992-1-1:2004, provision that shear force should be reduced by the coefficient β=av/2d is prescribed. Results of the experimental research, in correlation with shear strength calculated according to EN 1992-1-1:2004, are being analyzed in this paper. It has been established that the proposed reduction gives a significantly reduced magnitude of the design value of the load, which do not provide the necessary safety of calculation. [ABSTRACT FROM AUTHOR]

Abstract: There is a lot of usefulness measures of patterns in data mining. This paper is focused on the measures used in Formal Concept Analysis (FCA). In particular, concept stability is a popular relevancy measure in FCA. Experimental results of this paper show that high stability of a pattern in a given dataset derived from the general population suggests that the stability of that pattern is high in another dataset derived from the same population. At the second part of the paper, a new estimate of stability is introduced and studied. It es performance is evaluated experimentally. And it is shown that it is more efficient. [Copyright &y& Elsevier]

In this paper we study an opportunistic geographically constrained information sharing paradigm known under the name Floating Content (FC), considering two different mobility models that describe the behavior of pedestrians. We assume that users carrying their smartphones walk from one location to another and then stop for a while. Information transfers take place in the periods when users pause between movements. We develop analytical models to compute the performance metrics that characterize FC in this case and we validate analytical results with data collected during an experiment performed in a university campus. The comparison proves the accuracy of our analytical models. Moreover, results unveil the key relevance for FC performance of group dynamics in user movements. [ABSTRACT FROM AUTHOR]

This is the age of globalization and technological advancements. Globalization and technological advancement brought plenty of opportunities and career options to the under graduating and post graduating population in India. English has emerged as the major language of this age. It has become a global language in the present era. Millions of people want to learn English language today. As far as India is concerned, English is the second language in India. However, it is found that most of the students of undergraduate classes and postgraduate classes are poor in English. So as teachers, we have to take lots of efforts for making students use the language in their day today use in and outside of the classroom. We also need to take technological help. This paper is an attempt to find out how mobile applications (Apps) can be useful in the classroom to teach English language. [ABSTRACT FROM AUTHOR]

Due to environmental safety and miniaturization requirement along with better temperature matching with heat source, CO 2 transcritical power cycle (CTPC) has recently been gaining a lot of attention for application to waste heat recovery from internal combustion engines. In this paper, a constructed kW-scale CTPC system was dynamically tested to extract energy from exhaust gas of a heavy-duty diesel engine. The preliminary experiments were conducted under engine condition (1100 rpm, 50% load) with two operating modes: the constant valve opening and the constant pump speed. In order to characterise the dynamic process, the measuring system recorded data every second and also time constant and settling time are employed in data processing. The results show that valve inlet pressure follows the external changes timely, while temperatures respond a little slowly. The time constant of the current system is rather small showing from 20 to 25 seconds, which indicates an excellent capability of CTPC system of dealing with highly transient heat sources. In addition, predicted net power output and thermal efficiency show an upward trend with the increase of pressure ratio. Within the scope of these tests, CTPC system expects a maximum net power output of 1.34 kW and a maximum thermal efficiency of 3.54%. [ABSTRACT FROM AUTHOR]

The vacuum membrane dehumidification and dew point evaporative cooling are potential technologies to handle the latent and sensible heat of the air, respectively. This paper proposes a hybrid system of vacuum membrane dehumidifier and dew point evaporative cooler for air conditioning. A horizontal counter-flow dew point evaporative cooler was designed and developed. The transient and steady-state characteristics of the cooler were judiciously examined. The cooling potential of the cooler itself and the combined system with a membrane dehumidifier were then investigated and compared. Key findings that emerged from this study include: (1) the dew point evaporative cooler alone delivers the product air temperature at 24.8 °C under the hot and humid condition, with the wet bulb effectiveness of 1.05; (2) the hybrid cooling system is able to reduce the ambient humidity to 8.2 g/kg, and the ambient temperature is cooled to below 18.5 °C. [ABSTRACT FROM AUTHOR]

The dew point evaporative cooling technology is a potential substitute for the conventional vapor compression chillers in the air conditioning systems. Most of the existing studies focus on the thermodynamic analysis of the dew point evaporative cooler under various conditions. As the dominant physical mechanism, the in-depth heat and mass transfer phenomena have yet been studied. In this paper, we propose a detailed investigation on the heat and mass transfer process of the counter-flow dew point evaporative cooler. An experimental setup was established to measure the temperature or humidity distributions of the supply air, working air and water film. The heat and mass transfer coefficients were calculated via the temperature and humidity distributions. Concurrently, a 2-D mathematical model was developed to predict the experimental results of the cooler based on the momentum, continuity, energy and species balance equations. Key results that emerged from this study include: (1) the governing dimensionless numbers/groups in the cooling process are determined; (2) the Nusselt number and Sherwood number, which reveal the intensity of the convective heat and mass transfer, are studied with reference to those dimensionless groups. [ABSTRACT FROM AUTHOR]

With advances in information and communication technologies (ICT), organizations of various forms now deploy an increasing number of ICT-enabled persuasive systems in several domains. Traditional computer-mediated communication (CMC) theories mainly focus on the effectiveness of media in the synchronous/asynchronous spectrum for effectively matching medium with communication task. The contemporary communication environment is rich with asynchronous channels such as email, Web, and text messaging, which makes it important to go beyond synchronicity and determine the nuances among various asynchronous channels. No rigorous research has compared the effectiveness of these channels in the persuasive systems domain where organizations use technology to persuade users to modify their behavior in a direction that they mutually agree to be desirable. In this paper, we study the effectiveness of CMC and the strategy used to frame the persuasive message. We explore persuasive strategies of praising, reminding, suggesting, and rewarding for health behavior and promotion. We model user experience as a mediator between channel strategy combinations and persuasive effectiveness. Through controlled user studies, we compared sixteen combinations of communication channel and persuasive strategy with or without emoticons. We found that channel/strategy combinations affect persuasive effectiveness (mediated by user experience) in varying degrees. Our findings contribute to the body of CMC and persuasive system knowledge and have practical implications for online advertising, health promotion, and persuasive technology design. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a simple velocity-headway relation is used to describe the pedestrian following behavior in the single-file passageway. Single-file pedestrian movement experiment was conducted to obtain the distance headway-velocity data and nonlinear curve fitting to the data are executed to gain a good form of the velocity-headway equation. Referring to the ideas of car-following models, the velocity- headway relation is used as the fundamental optimal velocity function and then we adopts the optimal velocity model to study the pedestrian following behavior. Linear stability analyses give the phase diagram of the distance headway-sensitivity. Corresponding simulations are executed and the fundamental diagrams of the mean velocities are compared with the results of experiments carried out in China and Germany, and it is found that the model proposed in this paper is applicable for pedestrian following behavior. Simulation result also verifies the different physiological body sizes or psychological space requirements will have significant influence on the mean velocity. It is hoped for that this study would be useful for the evaluation of pedestrian movement in public buildings or egress passageways and the development of evacuation models. [Copyright &y& Elsevier]

Abstract: In this study, a very basic experiment of single-file bicycles moving in a circle passage was conducted. A video processing method was used to extract the relevant data such as trajectories, velocity, density, flow rate, time headway and so on. Afterwards, the relations between them were explained in detail. The relation between the flow rate and the density indicated that the flow rate is in proportion with the density before the congestion appears. It is also found that the interval between two bicycles is long but the time headway decreased as the density increased when the bicycles can move freely, while the situation is opposite when congestion occurs. Some of the results in this paper consist with those of other researchers. The purpose of this experiment is to provide basic experimental data and fundamental diagrams for single-file bicycles’ following movement. Results provided in this paper might be useful for validating related models and designing facility. [Copyright &y& Elsevier]

Abstract: Firstly this paper designs solar heating biogas fermentation system, its volume is 6m3, and than calculates digester''s heat load based on Hohhot''s weather data. Finally, a U-tube collector system was carried out for 5 month experiment, this paper use October''s experimental data, looking for the heat matching relationship between the solar collector system and biogas fermentation system. We can conclude that at Hohhot, in October, the heat was absorbed by 2m2 solar collectors that was ran 8hours can met the 6m3 digester ‘s fermentation heat demands. [Copyright &y& Elsevier]

Abstract: A non-linear PID controller based on single-point suspension system was designed at first in this paper, and it was analyzed that its gain is higher than that of linear PID controller with little error. It is indicated by simulation that the dynamic performance of closed-loop system was satisfying when its load changed, so its robust performance of nonlinear PID controller is better than that of PID controller. Refined computation of levitation damping was discussed according to robust observer, which included normalization and digital processing of input signals. It was validated by experiment that single-bogy system can be stabilized by using the non-linear PID controller and damping designed in this paper, and the vehicle-coupled-guideway vibration was restrained, which proved that computation method of damping in this paper is correctly. [Copyright &y& Elsevier]

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One of the most rapidly growing fields within modern economics is so-called behavioural economics, which stems from an effort to enrich the methodological and conceptual apparatus of traditional economics with approaches and concepts originating in psychology. This paper belongs to this research stream, but the focus of the paper specifically on the decision-making of buyers makes it relevant also for marketing. In traditional economics, buyer behaviour is usually modelled under the assumption of full information either on prices and their locations within the market or at least on the probability distribution of prices in the market. Neither of these assumptions seems appropriate in some cases such as when the buyer enters the specific market only very infrequently (e.g., markets for durables, but in the opposite role also the labour market). This paper, using the method of an economic experiment, studies the search rules that buyers might use in this case of extreme lack of information on prices. The paper identifies three general search heuristics: Adaptation Heuristic (a priori idea of the highest acceptabe price changes in the light of actual price quotes observed during the search), Bargain Heuristic (idea of the highest acceptabe price is located at a certain distance below the estimated average price calculated from price quotes observed during the search) and Improvement Heuristic (idea of the highest acceptabe price is equla to the forecast of the price quote to be observed in the next search step, increased by the cost of this step). On the bais of these three heuristics, the paper derives three specific search rules and, using data from a small-scale experiment, estimates parameters of the rules. [ABSTRACT FROM AUTHOR]

In the first part of the article I have dealt with the role and place of behavioral economics in the economic sciences. Classical economic theories are criticized by the behavioral economy. We think we are rational beings and that we make logical decisions based on the information we have at our disposal. In fact, we have our own cognitive limitations that can lead to hasty decisions or confusing judgments; the real individual is a complex person, with actions that result in failures and incomprehensible behaviors for the economics Behavioral economics is trying to explain why individuals often make irrational choices, and why decisions they take do not follow exactly the patterns predicted by classical and neoclassical economic models. This paper is trying to assess the individual behavior involved in the decision making process in the university space. This article describes aloso a series of experiments on behavioral economics. The experiments are from university life and contest the hypothesis of the perfectly rational person's existence in making decisions and the neoclassical economic theories and models that are based only on the premise of the existence of homo oeconomicus rationalis. Observations and experiments conducted with students at Constantin Brancusi University in Târgu-Jiu are relevant in challenging the hypothesis of perfect rationality, preference stability, perfect information and market efficiency. The research method used in this article is the experiment. Study results are useful for academic management. [ABSTRACT FROM AUTHOR]

Vibration problems concerning lightweight, flexible long-span floors and cantilever grandstands structures in engineering practice generally arise from crowd loading. Predicting the dynamic response of these structures due to crowd bouncing load has therefore become a critical aspect of structural vibration serviceability evaluation during live concerts or other large entertainments in public structures. This paper experimentally investigates synchronization of crowd bouncing. A crowd of approximately 50 persons participated in the experiment with each individual wearing three reflective markers on his/her clavicle. Verification experiments confirmed that the mean value of trajectories of the three markers can be employed to represent movement of center-of-mass of the person. Trajectories of all markers on all test participants were recorded simultaneously through a three-dimensional motion capture system consisting of 18 cameras. Various crowd densities and bouncing frequencies ranging from 1.5Hz to 3.5Hz with an interval of 0.1Hz were considered in the experiment. Moreover, various special test cases were conducted wherein each test participant was asked to wear an eye-patch avoid any visual influences. Preliminary analysis on the experimental data shows that for any of the fixed-frequency test cases the bouncing crowd can’t be perfectly synchronized. Each individual’s bouncing frequency in a crowd is found as following a normal distribution. [ABSTRACT FROM AUTHOR]

Currently used design methods for solution of lateral torsional buckling are based on critical moment approach. This solution is also implemented in design codes but it is limited for use of single symmetric cross section only. The analytical solution of mono symmetric cross-section by critical moment is patterned on the theory of thin walled elastic beams by Vlasov [1] . In spite of the fact that this theory is known for many decades, the practical elaborated approach for solution of asymmetrical cross section is still the actual problem to solve. Nowadays the FEM based numerical models are the powerful instrument for detailed analysis of such kind of structure. However, there are still problems with definition of all imperfections and boundary conditions. Also the modelling of load effects during the loading procedure remains usually difficult. The most valuable source of information is the experiment. The goal of research which is presented in this paper is the experimental and theoretical analysis of cross section which can be asymmetrical. Particularly there are experimental test of several beams of selected cross-section shapes described and analysed. The main idea of those experiments was to observe the differences in behaviour between single symmetric cross-section and the slightly asymmetric one. Results of those experiments will serve as a base for further theoretical part of the research. [ABSTRACT FROM AUTHOR]

The paper points to links between the scientific - technological development of structures of passenger cars of the recovery and hydraulic equipment used in rescue operations in the Fire and Rescue Service. At the same time it presents the results of an experiment that aimed to determine the time dependence of cutouts on the type and size of materials used in passenger cars. The experiment was applied to the pillars A and B and is based on the possibility of approach to optimizing technical procedures for rescue operations in road accidents in road transport. [ABSTRACT FROM AUTHOR]

The paper refers to the strengthening of doubly symmetric columns under load by welded plates. A validated numerical study containing more than 500 models was performed to question the currently used design procedures. These procedures are not unified but vary greatly in different countries. The overly conservative design approach used in the Czech Republic contrasts with the approach completely neglecting the effect of preload commonly used in the USA. The effect of various parameters on the flexural buckling resistance of columns strengthened under load was investigated. The selected parameters were the thickness of the strengthening flange, the column length, the initial bow imperfection, the preload magnitude and the direction of the axis which is pinned while the other axis is fixed. Several conclusions were reached from provided results and a simple analytical method is proposed. The load under which the column is strengthened weakens the column but only slightly. [ABSTRACT FROM AUTHOR]

The sandwich panels have been widely used as members of roof and wall cladding. In addition to their primary function, they can provide lateral and torsional restraints to the supporting members and therefore contribute to their buckling resistance. The availability of the provided restraints is influenced by the direction of the load applied to the surfaces of the panels. For the uplift load, no torsional restraint is conservatively considered due to reduction of the contact area between the panels and the supporting metal members. Possible small rate of the torsional restraint should be verified by experimental investigation. The paper focuses on the experimental verification of the torsional restraint provided to steel purlins of thin-walled cold-formed cross-sections by adjacent sandwich panels. For the first series of tests a simple test set-up with no external load applied to the surface of the panel was utilized. The second series comprises tests of the torsional restraint provided to steel purlins by sandwich panels under uplift load. A complex test set-up taking into account the external load applied to the surfaces of the panels was used. The results of both test approaches are compared and the influence of the uplift load on the torsional restraint for the tested specimens is evaluated. [ABSTRACT FROM AUTHOR]

This paper deals with the modeling of the load test of vertical resistance of reinforced concrete piles. The pile is a part of a group of piles with reinforced concrete heads. The head is pressed with steel arches of a bridge on highway Jablonov - Studenec. Pile model is created in ANSYS with several models of foundation having properties found out from geotechnical survey. Finally some crucial results obtained from computer models are presented and compared with these obtained from experiment. [ABSTRACT FROM AUTHOR]

This paper deals with experimental research of stability behaviour of laminated structural glass beams. The purpose of the research is the evaluation of lateral-torsional buckling resistance and actual behaviour of the beams due to absence of standards for design of glass load-bearing structures. The experimental research follows the previous one focusing on measuring of initial geometrical imperfections of glass members and experimental evaluation of flexural buckling resistance of structural glass columns. Within the frame of the research 9 specimens were tested. All of them were of the same dimensions - length 2400 mm and width 280 mm but different thicknesses - 12, 16, 20 mm. All the beams were composed of two annealed glass panes bonded together by PVB foil. Beams were loaded by couple of forces symmetrically situated to the mid-span and supports complied with fork boundary conditions. Specimens were loaded by constantly increasing force up to failure. During testing lateral deflection, vertical deflection, angle of torsion and normal stresses at mid-span were measured. Maximum bending moment achieved during testing has been adopted as lateral-torsional buckling resistance. From these values were calculated characteristics and design values according to the EN 1990. Experiment results were compared with lateral torsional buckling resistance calculated according to the buckling curves approach. [ABSTRACT FROM AUTHOR]

The article reports the results of a test of the Spiral of Silence Theory that was introduced by Elizabeth Noelle-Neumann. The real process of the spiral of silence assumes that people (in the putative position of a minority) do not express their opinion or join the opinion of the majority because they have a fear of isolation. Tamás Bodor has argued that the theory does not function in all tests when (1) the process is timelimited, meaning that we can observe a public debate of an actual problem only for a short time and with the condition that the public forms two opposing opinion camps and (2) the key dependent variable is measured in an inappropriate way (e.g. researchers interview participants using a questionnaire on the hypothetical willingness to speak out). The solutions used with our test were: (1) we used four controversial themes, resulting in a greater probability of finding the functional process of the increased silence of the minority, and (2) we measured the key dependent variable as speaking behaviour during the laboratory experiment. Two laboratory experiments were part of this research; the first contained 42 and the second contained 43 students from the University of West Bohemia in Pilsen. The experiments had the same design: (1) measuring of attitudes through a questionnaire (phase 1); (2) discussion on an internet blog (an anonymous online environment); and (3) discussion in a focus group (an offline environment). The first half of the respondents discussed anonymously online (phase 2) and thereafter offline (phase 4), and the other half participated in the experiment in the reverse order of environments. We measured attitudes again in phase 3 and at the end of the experiment (phase 5). The article investigates whether participants with minority attitudes are more frequently silent and how this relationship is moderated by fear of isolation and by the communication environment. Our results prove that the probability a participant will speak her opinion rises in an anonymous online environment. The results support the Spiral of Silence Theory - participants expressing minority attitudes are more frequently silent, but only when they express higher fear of isolation. Participants expressing lower fear of isolation are not influenced by minority or majority attitudes regarding the speaking of their opinion. Finally, the main contribution of our paper is the experimental replication of results obtained through hypothetical measures. [ABSTRACT FROM AUTHOR]

The paper deals with method for dynamic experiment of parts of car radial tyres. The aim of research work of authors is also propose and evaluate the experimental procedures for cyclic loading of selected parts of tyres with textile reinforcement and rubber matrix. The universal testing device Autograph AG-X plus 5 kN – Schimadzu with video-extensometer with test mode Control of software Trapenzium X was used for experiments. The five cycle loop were used. Every cycle loop consisted of five cycles, every cycle is defined as loading to certain percent of elongation and unloading to certain percent of elongation. The fifth cycle can be used as steady state for comparison of behaviour between specimens with different cord angle. Knowledge about characteristics of dynamic experiment such as cyclic tensile loading is necessary for the verification analysis between experiments and computational modeling of tyres by FEA. Also the determination of material parameters from experimental data will be used as input data to computational modeling of tyres. The results will be also applied in the case of the composites with the woven and nonwoven textile reinforcement and moreover, these results can be used in such conditions where the mentioned composites are exposed to the cyclic loading at unsteady temperature: tyre casing, conveyor belts, etc. [ABSTRACT FROM AUTHOR]

Egon Brunswik coined and defined the concepts of ecological validity and representative design, which are both essential to achieve external validity. However, research in HCI has inconsistently and incorrectly used Brunswik's concept of ecological validity, which prevents the field from developing cumulative science and from generalizing the findings of user experience (UX) evaluations. In this paper, I present ECOVAL, a framework I built on Brunswik's ideas. On the one hand, ECOVAL helps HCI researchers describe and assess the ecological validity of cues in UX evaluations. On the other hand, ECOVAL guidelines--formulated as a step-by-step procedure--help HCI researchers achieve representative design and, therefore, increase external validity. An industrial case study demonstrates the relevance of ECOVAL for achieving representative design while conducting formative UX testing. In discussing the case study, I describe how ECOVAL can help HCI researchers assess and increase the validity of UX experiments and generalize UX findings. I also illustrate the trade-offs between internal and external validities and UX resources that inevitably arise when one conducts UX experiments. From the results, I sketch avenues for future research and discuss the related challenges that future work should address. [ABSTRACT FROM AUTHOR]

The first CO 2 monitoring field lab at the Ressacada Farm, in the Southern region of Brazil, started in 2011 and until 2015 offered an excellent opportunity to run controlled CO 2 releases experiments in soil and shallow subsurface through vertical injection wells. This paper focus on the presentation and comparison of the results obtained at the last campaign realized at this site in August 2015. The results integrate a time-lapse monitoring experiment of CO 2 migration in both saturated and unsaturated sand-rich sediments and soil, using soil CO 2 flux measurements and subsurface gas analyses through CO 2 concentrations (ppm) and carbon isotope ratios (δ 13 C of CO 2 ). The CO 2 flux results in the studied area showed an increase in the flux values according to the increasing of injection rate and along the campaign are directed to the southwest portion of the area. However, even by injecting large amounts of CO 2 , fluxes are greatly reduced when it rains. The gas analysis also showed an increase in CO 2 concentrations according to the increasing of the injection rate mainly in the superficial levels of the monitoring wells (0.5m and 2m depth). The δ 13 C of CO 2 found on the 3 rd injection day showed the presence of CO 2 injected and demonstrate that the sampling methodology with vacutainer vial was effective, since there is no atmospheric contamination. The correlation of isotopic analysis were consistent with the results of concentrations and CO 2 fluxes and thus, it is clear that the CO 2 breakthrough occurred from the 3 rd day of injection, while were obtained the largest CO 2 fluxes, the higher gas concentrations in the subsurface, as well as the industrial origin of δ 13 C of CO 2 . [ABSTRACT FROM AUTHOR]

In the last years, several innovations have been introduced in the field of building envelope research and development. To bridge the gap between research and commercially available products, one of the key step is to evaluate these technologies in 1:1 scale and under real boundary conditions. For this purpose, test in outdoor full-scale facilities in complement with dynamic numerical simulation, allow to assess the performances of these complex envelope components, systems or whole building. In this framework a new versatile facility, named FACT (FACade Tool), is under construction in the south-eastern France (CEA- INES platform – Le Bourget du Lac) for building envelope components test. This new full-scale tool will be dedicated to infield evaluation of: opaque and transparent elements, light-weight and massive façades, different thickness and heights and different geometry of the indoor environment. In this paper it is presented the design phase, the concept and the working principle of the facility. The layout definition was supported by preliminary simulations and the results of this modelling activity are discussed in order to guide the construction of the facility and to outline the experimental protocol for the next campaigns in FACT. [ABSTRACT FROM AUTHOR]