bluuebunny/crossref_metadata_2025 huggingface dataset:
BlueDetect: An iBeacon-Enabled Scheme for Accurate and Energy-Efficient Indoor-Outdoor Detection and Seamless Location-Based Service
Authors: Zou Han , Jiang Hao , Luo Yiwen , Zhu Jianjie , Lu Xiaoxuan , Xie Lihua
Published: February 2016

The location and contextual status (indoor or outdoor) is fundamental and critical information for upper-layer applications, such as activity recognition and location-based services (LBS) for individuals. In addition, optimizations of building management systems (BMS), such as the pre-cooling or heating process of the air-conditioning system according to the human traffic entering or exiting a building, can utilize the information, as well. The emerging mobile devices, which are equipped with various sensors, become a feasible and flexible platform to perform indoor-outdoor (IO) detection. However, power-hungry sensors, such as GPS and WiFi, should be used with caution due to the constrained battery storage on mobile device. We propose BlueDetect: an accurate, fast response and energy-efficient scheme for IO detection and seamless LBS running on the mobile device based on the emerging low-power iBeacon technology. By leveraging the on-broad Bluetooth module and our proposed algorithms, BlueDetect provides a precise IO detection service that can turn on/off on-board power-hungry sensors smartly and automatically, optimize their performances and reduce the power consumption of mobile devices simultaneously. Moreover, seamless positioning and navigation services can be realized by it, especially in a semi-outdoor environment, which cannot be achieved by GPS or an indoor positioning system (IPS) easily. We prototype BlueDetect on Android mobile devices and evaluate its performance comprehensively. The experimental results have validated the superiority of BlueDetect in terms of IO detection accuracy, localization accuracy and energy consumption.
Determination of Optimum Window to External Wall Ratio for Offices in a Hot and Humid Climate
Authors: Alibaba Halil
Published: February 2016

Heat loss and gain through windows has a very high impact on the thermal comfort of offices. This paper analyzes a standard low energy consumption university office that has a standard envelope. Dynamic thermal simulations with EDSL Tas software, a predicted mean vote (PMV), and a predicted percentage of dissatisfied (PPD) with all local discomfort as stated in ASHRAE, ISO 7730: 2005, EN 15251: 2007 were used for thermal sensation, in order to optimize the best window to external wall proportion in a hot and humid climate that exists in the Famagusta case study. A simulated office building is oriented east to west in order to take advantage of the wind direction. In May 45% (PPD < 6%–0.7% open window), 93% (PPD < 10–0.2 open window), and 97% (PPD < 15%–0.1% open window) thermal comfort scores are obtained when the window to external wall ratio (WWR) is 10%. In October 43% (PPD < 6%–0.7% open window), 86% (PPD < 10–0.2 open window), and 92% (PPD < 15%–0.1% open window) thermal comfort scores are obtained when the WWR is 10%. In September 49% (PPD < 10% full open window) and 51% (PPD < 15%–0.1% open window) thermal comfort scores are obtained when the WWR is 10%.
Venom of Parasitoid Pteromalus puparum Impairs Host Humoral Antimicrobial Activity by Decreasing Host Cecropin and Lysozyme Gene Expression
Authors: Fang Qi , Wang Bei-Bei , Ye Xin-Hai , Wang Fei , Ye Gong-Yin
Published: February 2016

Insect host/parasitoid interactions are co-evolved systems in which host defenses are balanced by parasitoid mechanisms to disable or hide from host immune effectors. Here, we report that Pteromalus puparum venom impairs the antimicrobial activity of its host Pieris rapae. Inhibition zone results showed that bead injection induced the antimicrobial activity of the host hemolymph but that venom inhibited it. The cDNAs encoding cecropin and lysozyme were screened. Relative quantitative PCR results indicated that all of the microorganisms and bead injections up-regulated the transcript levels of the two genes but that venom down-regulated them. At 8 h post bead challenge, there was a peak in the transcript level of the cecropin gene, whereas the peak of lysozyme gene occurred at 24 h. The transcripts levels of the two genes were higher in the granulocytes and fat body than in other tissues. RNA interference decreased the transcript levels of the two genes and the antimicrobial activity of the pupal hemolymph. Venom injections similarly silenced the expression of the two genes during the first 8 h post-treatment in time- and dose-dependent manners, after which the silence effects abated. Additionally, recombinant cecropin and lysozyme had no significant effect on the emergence rate of pupae that were parasitized by P. puparum females. These findings suggest one mechanism of impairing host antimicrobial activity by parasitoid venom.
Le risque inondation en ville : une impossible territorialisation ? (Urban flood risk : an impossible territorialization ?)
Authors: Meschinet de richemond Nancy
Published: February 2016

A travers l 'étude de risques urbains, et notamment les inondations, un changement de perspective se fait jour à partir des années 1990 dans la manière d'envisager les territoires du risque non plus en fonction de l'aléa mais en fonction des vulnérabilités et des conséquences des catastrophes. Les inondations en ville montrent combien le risque ne se surimpose pas à l 'espace urbain existant mais en constitue une composante intrinsèque. Mais si la gestion des inondations en ville s 'appuie sur des outils qui se veulent aptes à prendre en compte les réalités territoriales contemporaines (PPRI), de nombreux exemples montrent, en pratique, combien cette territorialisation du risque inondation reste marquée par la spatialisation de l'aléa et peine à intégrer les territoires fragmentés de la vulnérabilité.
Prévention du risque inondation par ruissellement en milieu urbain : l'exemple de la métropole lilloise (Preventing runoff flood risk in an urban environment : the example of the Lille metropolis)
Authors: scarwell Helga-Jane , Salvador Pierre-Gil , Schmitt Guillaume
Published: February 2016

A measure -meant as an incentive to encourage provision making, modulated insurance premiums according to the degree of hazard for a risk of identical nature in those municipalities not endowed with a state flood risk prevention plan (PPRi) in the five years prior to any new occurrence of flooding. There followed a wave of PPRi registrations in the Nord-Pas de Calais Region. These PPRis were indifferently framed for one or more types of risk at the municipal level or according to a river basin. As stated by government authorities "some natural catastrophe orders have very possibly been unduly prescribed. However these decrees, for lack of legibility, do not allow yet to identify the areas where PPRIs are to be maintained or lifted" [DDE, June 13 th 2006]. Our project aims at conducting research around risk assessment. The aim being to come up with a model for evaluation which will be both scientifically and technically reproducible as well as to introduce a nomenclature of hierarchized PPRis based on indicators of vulnerability-ultimately helping to discriminate between PPRis : those to be preserved from those which are expendable.
Comparison of goniometric measurements of the stifle joint in seven breeds of normal dogs
Authors: Ocal Mehmet , Sabanci Seyyid
Published: February 2016

Objective: To compare the goniometric measurements of the stifle joint in seven dog breeds, and to determine the relationship among goniometric measurements, age, body weight, tibial plateau angle, crus and thigh circumferences, and widths of quadriceps, hamstring, and gastrocnemius muscles in healthy dogs.

Methods: We used a total of 126 dogs from seven different breeds, and recorded the angle of the stifle joint at standing, extension, and flexion together with the range of motion (ROM). The circumferences of the thigh and crus were also measured. Medio -lateral radiographic projections of the tibia and the femur were obtained from the dogs, and the tibial plateau angles, as well as the widths of quadriceps, hamstring, and gas -trocnemius muscles, were measured from these images.

Results: Neither the sex of the dog nor the differences in the side measured affected the goniometric measurements of the stifle joint. The standing, extension, flexion, and ROM angles were different among the breeds. The standard deviations of the standing and extension angles were small relative to their means, but the standard deviations of the flexion angle were large relative to their means in all breeds. Body weight and muscular measurements were the most influential factors on the stifle flexion angle and ROM.

Clinical significance: Breed differences, body weights, and muscle mass should be taken into consideration during assessment of the stifle function using goniometric measurements.
Computed tomographic arthrography of the normal dromedary camel carpus
Authors: Marzok Mohamed , Eshra Eman , Badawy Adel
Published: February 2016

The aim of this prospective cadaveric study was to provide a detailed computed tomographic (CT) reference of the carpal joint in healthy dromedary camels. Twelve forelimbs of six apparently healthy camels were used. Computed tomographic imaging of 12 normal cadaveric camel carpal joints was performed before and after intra-articular administration of iodinated contrast medium. Transverse CT images were reconstructed in dorsal and parasagittal planes. The six carpal bones, the radial trochlea, and the proximal articular surface of the metacarpal bones were clearly visible on CT images with the bone setting window. Radiocarpal, carpometacarpal, transverse intercarpal, medial and lateral palmer intercarpal, middle intercarpal, accessory carpoulnar and medial and lateral collateral ligaments, carpal canal, joint capsule, and the extensor and flexor tendons were identified on CT images with the soft-tissue setting window. Postcontrast CT images provided better delineation of intercarpal ligaments, the capsular compartments and recesses. Results indicated that the osseous and the clinically important soft tissue structures of the dromedary camel carpal joint could be identified using CT and CT arthrography. The CT data of this study will serve as a basis for diagnosis of carpal problems in camels.
ASAS J083241+2332.4: A NEW EXTREME LOW MASS RATIO OVERCONTACT BINARY SYSTEM
Authors: Sriram K. , Malu S. , Choi C. S. , Vivekananda Rao P.
Published: February 2016

We present the R- and V-band CCD photometry and Hα line studies of an overcontact binary ASAS J083241+2332.4. The light curves exhibit totality along with a trace of the O’Connell effect. The photometric solution indicates that this system falls into the category of extreme low-mass ratio overcontact binaries with a mass ratio, q ∼ 0.06. Although a trace of the O’ Connell effect is observed, constancy of the Hα line along various phases suggest that a relatively higher magnetic activity is needed for it to show a prominent fill-in effect. The study of O–C variations reveals that the period of the binary shows a secular increase at the rate of dP/dt ∼ 0.0765 s years−1, which is superimposed by a low, but significant, sinusoidal modulation with a period of ∼8.25 years. Assuming that the sinusoidal variation is due to the presence of a third body, orbital elements have been derived. There exist three other similar systems, SX Crv, V857 Her, and E53, which have extremely low mass ratios and we conclude that ASAS J083241+2332.4 resembles SX Crv in many respects. Theoretical studies indicate that at a critical mass ratio range, q
critical = 0.07–0.09, overcontact binaries should merge and form a fast rotating star, but it has been suggested that q
critical can continue to fall up to 0.05 depending on the primary's mass and structure. Moreover, the obtained fill-out factors (50%–70%) indicate that mass loss is considerable and hydrodynamical simulations advocate that mass loss from L
2 is mandatory for a successful merging process. Comprehensively, the results indicate that ASAS J083241+2332.4 is at a stage of merger. The pivotal role played by the subtle nature of the derived mass ratio in forming a rapidly rotating star has been discussed.
GLOBAL MODELING OF NEBULAE WITH PARTICLE GROWTH, DRIFT, AND EVAPORATION FRONTS. I. METHODOLOGY AND TYPICAL RESULTS
Authors: Estrada Paul R. , Cuzzi Jeffrey N. , Morgan Demitri A.
Published: February 2016

We model particle growth in a turbulent, viscously evolving protoplanetary nebula, incorporating sticking, bouncing, fragmentation, and mass transfer at high speeds. We treat small particles using a moments method and large particles using a traditional histogram binning, including a probability distribution function of collisional velocities. The fragmentation strength of the particles depends on their composition (icy aggregates are stronger than silicate aggregates). The particle opacity, which controls the nebula thermal structure, evolves as particles grow and mass redistributes. While growing, particles drift radially due to nebula headwind drag. Particles of different compositions evaporate at “evaporation fronts” (EFs) where the midplane temperature exceeds their respective evaporation temperatures. We track the vapor and solid phases of each component, accounting for advection and radial and vertical diffusion. We present characteristic results in evolutions lasting 2 × 105 years. In general, (1) mass is transferred from the outer to the inner nebula in significant amounts, creating radial concentrations of solids at EFs; (2) particle sizes are limited by a combination of fragmentation, bouncing, and drift; (3) “lucky” large particles never represent a significant amount of mass; and (4) restricted radial zones just outside each EF become compositionally enriched in the associated volatiles. We point out implications for millimeter to submillimeter SEDs and the inference of nebula mass, radial banding, the role of opacity on new mechanisms for generating turbulence, the enrichment of meteorites in heavy oxygen isotopes, variable and nonsolar redox conditions, the primary accretion of silicate and icy planetesimals, and the makeup of Jupiter’s core.
NONLINEAR COLOR–METALLICITY RELATIONS OF GLOBULAR CLUSTERS. VI. ON CALCIUM II TRIPLET BASED METALLICITIES OF GLOBULAR CLUSTERS IN EARLY-TYPE GALAXIES
Authors: Chung Chul , Yoon Suk-Jin , Lee Sang-Yoon , Lee Young-Wook
Published: February 2016

The metallicity distribution function of globular clusters (GCs) in galaxies is a key to understanding galactic formation and evolution. The calcium II triplet (CaT) index has recently become a popular metal abundance indicator thanks to its sensitivity to GC metallicity. Here we revisit and assess the reliability of CaT as a metallicity indicator using our new stellar population synthesis simulations based on empirical high-resolution fluxes. The model shows that the CaT strength of old (>10 Gyr) GCs is proportional to [Fe/H] below −0.5. In the modest metal-rich regime, however, CaT does not increase anymore with [Fe/H] due to the little contribution from coolest red giant stars to the CaT absorption. The nonlinear nature of the color–CaT relation is confirmed by the observations of GCs in nearby early-type galaxies. This indicates that the CaT should be used carefully when deriving metallicities of metal-rich stellar populations. Our results offer an explanation for the observed sharp difference between the color and CaT distributions of GCs in the same galaxies. We take this as an analogy to the view that metallicity–color and metallicity–Lick index nonlinearity of GCs is primarily responsible for their observed “bimodal” distributions of colors and absorption indices.
CONVERGING SUPERGRANULAR FLOWS AND THE FORMATION OF CORONAL PLUMES
Authors: Wang Y.-M. , Warren H. P. , Muglach K.
Published: February 2016

Earlier studies have suggested that coronal plumes are energized by magnetic reconnection between unipolar flux concentrations and nearby bipoles, even though magnetograms sometimes show very little minority-polarity flux near the footpoints of plumes. Here we use high-resolution extreme-ultraviolet (EUV) images and magnetograms from the Solar Dynamics Observatory (SDO) to clarify the relationship between plume emission and the underlying photospheric field. We find that plumes form where unipolar network elements inside coronal holes converge to form dense clumps, and fade as the clumps disperse again. The converging flows also carry internetwork fields of both polarities. Although the minority-polarity flux is sometimes barely visible in the magnetograms, the corresponding EUV images almost invariably show loop-like features in the core of the plumes, with the fine structure changing on timescales of minutes or less. We conclude that the SDO observations are consistent with a model in which plume emission originates from interchange reconnection in converging flows, with the plume lifetime being determined by the ∼1 day evolutionary timescale of the supergranular network. Furthermore, the presence of large EUV bright points and/or ephemeral regions is not a necessary precondition for the formation of plumes, which can be energized even by the weak, mixed-polarity internetwork fields swept up by converging flows.
LOFAR, VLA, AND CHANDRA OBSERVATIONS OF THE TOOTHBRUSH GALAXY CLUSTER
Authors: van Weeren R. J. , Brunetti G. , Brüggen M. , Andrade-Santos F. , Ogrean G. A. , Williams W. L. , Röttgering H. J. A. , Dawson W. A. , Forman W. R. , Gasperin F. de , Hardcastle M. J. , Jones C. , Miley G. K. , Rafferty D. A. , Rudnick L. , Sabater J. , Sarazin C. L. , Shimwell T. W. , Bonafede A. , Best P. N. , Bîrzan L. , Cassano R. , Chyży K. T. , Croston J. H. , Dijkema T. J. , Enßlin T. , Ferrari C. , Heald G. , Hoeft M. , Horellou C. , Jarvis M. J. , Kraft R. P. , Mevius M. , Intema H. T. , Murray S. S. , Orrú E. , Pizzo R. , Sridhar S. S. , Simionescu A. , Stroe A. , Tol S. van der , White G. J.
Published: February 2016

We present deep LOFAR observations between 120 and 181 MHz of the “Toothbrush” (RX J0603.3+4214), a cluster that contains one of the brightest radio relic sources known. Our LOFAR observations exploit a new and novel calibration scheme to probe 10 times deeper than any previous study in this relatively unexplored part of the spectrum. The LOFAR observations, when combined with VLA, GMRT, and Chandra X-ray data, provide new information about the nature of cluster merger shocks and their role in re-accelerating relativistic particles. We derive a spectral index of

at the northern edge of the main radio relic, steepening toward the south to

. The spectral index of the radio halo is remarkably uniform (

, with an intrinsic scatter of

). The observed radio relic spectral index gives a Mach number of

, assuming diffusive shock acceleration. However, the gas density jump at the northern edge of the large radio relic implies a much weaker shock (

, with an upper limit of

). The discrepancy between the Mach numbers calculated from the radio and X-rays can be explained if either (i) the relic traces a complex shock surface along the line of sight, or (ii) if the radio relic emission is produced by a re-accelerated population of fossil particles from a radio galaxy. Our results highlight the need for additional theoretical work and numerical simulations of particle acceleration and re-acceleration at cluster merger shocks.
Common Misunderstandings of Electricity: Analysis of Interview- Responses of Electrical Engineering Technology Students
Authors: Goris Tatiana V.
Published: February 2016

In the recent decade the wide body of research on misconceptions focused on establishing understandable schemes of why some scientific concepts are so difficult to understand for students in various Engineering Technology majors. The present interview-based, qualitative study of two student groups opened some interesting insides and explains common struggling of learning the basic electrical concepts. It had been observed that progressing from a freshman to a senior level, students developed strong technical/terminological vocabulary, but often they were unable to clear explain what those terms mean. Both student cohorts (from freshmen to seniors) continuously applied incorrect “water-analogy” to the concepts of current flow. Also, in majority of cases, they perceive electricity ontologically incorrect as a “Substance-that-can-be-used-up”.
How Accreditation Agencies can Help the Necessary Changes of HEIs Towards Sustainable Development Practices
Authors: Jolly Anne Marie , Mahieu Laurent
Published: February 2016

In our society, everybody seems concerned by sustainable development, however, when you discuss with European students, you realize that in many institutions, there is not much done and that for the time being it is always the same European universities that behave as "good students" and answer surveys and enquiries; it is necessary to find a way to make things evolve everywhere! Accreditation agencies are one of the solutions to improve the involvement of all the HEIs. The Commission des Titres d'Ingénieurs (CTI) is in France the body in charge of authorizing engineering universities the right to deliver the title of engineer. It states its own accreditation criteria that can evolve according to CTI's own ongoing reflexion or to the point of view of its stakeholders, as required by ENQA. Regarding social responsibility and SD CTI consulted for 3 years organisations directly concerned by SD and defined in February 2014 the item that must appear in HEI's self evaluation reports. Those points as well the demarche are presented in the paper
Global Diversity and Inclusion in Engineering Education: Developing Platforms toward Global Alignment
Authors: Delaine David Antoine , Tull Renetta , Sigamoney Rovani , Williams Darryl N.
Published: February 2016

This paper presents an exploratory investigation of global scale diversity and inclusion efforts within engineering education. The content is an expansion of work that was shared at the 2015 World Engineering Education Forum’s first special session on “Diversity & Inclusion in Global Engineering.” Diversity and Inclusion (D&I) are contextualized topics that shift objectives from country to country. The role of D&I in engineering education and practice has gained prominence in recent years due to the fact that engineers are facing increased need for global collaborations and are expected to be able to work in highly diverse teams and within different cultures. D&I initiatives in the field of engineering generally include gender, ethnicity, and national origin, and may include persons who are economically underprivileged and persons with disabilities. While the prominence of D&I has increased, international learning outcomes and collaborations within these efforts are limited. Within a global community a common platform would allow for the sharing of best practices and maximize learning opportunities and impact. By examining models from around the world, we can begin to consolidate, optimize, and disseminate the global benefits of D&I. In this work, various programs are reviewed as success cases because they have increased the numbers of underrepresented students who enroll in and graduate from STEM programs. The potential for solidarity amongst Diversity & Inclusion initiatives and programs in different regions of the world is explored. Efforts are made to determine what can be learned from synergies across D&I activities.
Improvement of Multi-Directional Positioning Path Accuracy of Industrial Robots with Rotary Tables
Authors: Schwienbacher Christoph , Meiners Finn , Kötter Tobias , Schüppstuhl Thorsten
Published: February 2016

It is very intricate to determine the parameters for a correct kinematic model to compensate robot inaccuracies by calibration. Whereas non model-based approaches to compensate multi-directional robot pose inaccuracies with the help of a correction matrix have the disadvantage of being time consuming due to the large number of measurements. This paper describes a more efficient non model-based method to compensate tool deviations by defining a minimized subspace for the robot, taking advantage of a rotary table. Necessary measuring poses are identified depending on the commanded paths and the inverse kinematics. The authors present the validation and verification of the method. They quantify and evaluate particularly the multi-directional positioning path accuracy.
Analysis on Chaotic Vibrations of the Magneto-Rheological Suspension System
Authors: Zhang Hai Long , Zhang Ning , Min Fu Hong , Wang En Rong
Published: February 2016

The magneto-rheological(MR) suspension system has been established, by employing the modified Bouc-wen force-velocity (F-v) model of magneto-rheological damper(MRD). The possibility of chaotic motions in MR suspension is discovered by employing nonlinear systems stability theory. With the bifurcation diagram and corresponding Lyapunov exponent spectrum diagrams detected through numerical calculation, we can observe the complex dynamical behaviors and oscillating mechanism of alternating periodic oscillations, quasi-periodic oscillations and chaotic oscillations with different profiles of road excitation, as well as the dynamical evolution to chaos by period-doubling bifurcations, saddle-node bifurcations and reverse period-doubling bifurcations.
Study on Internal Flow Field of the Afflux Device Based on CFD
Authors: Tu Chun Hui , Feng Guo Dong , Ni Jing , Shi Jian Guo , Zhou Hai Jiang
Published: February 2016

In the design of afflux device for the air dryer safety valve, a rational structure can improve the gas flow condition and suppress the pulsation noise as well. This paper designed an afflux device required little installation space, its physical and mathematical model were built up then. The simulation of the internal flow field is processed with the CFD (Computational Fluid Dynamics) software Fluent, which interprets the device inner structure’s impact on the flow field characteristics and silencing performance. The numerical simulation provides the designers with a reliable approach for the design of the afflux device.
Conceptual Design for the Performance Optimization of Compound Coaxial Helicopter
Authors: Cao Fei , Chen Ming , Wu Mei Li Wen
Published: February 2016

The purpose of this paper is to study the conceptual design and optimization of a compound coaxial helicopter. At the conceptual design phase, the compound coaxial helicopter design work was based on the conventional helicopter and fix-wing aircraft design method. The intersection of these aspects makes the design work more complex, thus, a program for the sizing and performance optimization was developed for the aircraft. The program included the total weight design, aerodynamic analysis, flight dynamics analysis, performance calculation and particle swarm optimization analysis. Under the restricted condition of the flight performance requirements, optimize the design parameters which make the weight efficiency factor decrease. Therefore, the study of optimum design process was warranted.
Effect of High Pressure Coolant on Tool Wear Phenomenon during Machining of Titanium Alloy Ti6Al4V
Authors: Pawar Pravin , Patil Sandip , Kekade Swapnil , Pawar Swapnil , Singh Rajkumar
Published: February 2016

Titanium alloys are referred to difficult-to-cut materials because of its some inferior properties like low thermal conductivity and high chemical reactivity. To improve machinability of these alloys one way is to use cutting fluids which removes the heat generated at the chip tool interface during the machining process. But coolant with low pressure and improper delivery is not able to break the vapor barrier created by high cutting temperature. The present work investigates the effect of using high pressure coolant system (50 Bar) on machinability of Ti6Al4V. The machinability was measured in terms of tool wear. The dominant tool wear mechanism was investigated by using scanning electron microscopy and energy dispersive X-ray analysis of worn out cutting tool surfaces. Abrasion wear on flank face and crater wear on the rake face was observed as a dominant tool wear mechanism. Along with this diffusion of titanium from the work surface to tool face is also confirmed.
Verification of the Geometric Parameters of the Ring-Core Method
Authors: Šarga Patrik , Menda František , Trebuňa František
Published: February 2016

The Ring-Core method is a semi-destructive method for residual stress determination inside materials. The evaluation of residual stresses using Ring-Core method requires complex analysis of the geometric parameters. This work deals with the uniformly distributed residual stress components through the material thickness.
Residual Fatigue Lives of Steam Turbine Blades
Authors: Balda Miroslav , Červená Olga
Published: February 2016

The paper deals with an assessment of blade tip movements based on precise time measurement known under abbreviation BTT - Blade Tip Timing. In addition to the common way of BTT data processing, a new Residual Fatigue Lives of Blades system (RFLB) proceeds further up to estimation of blade damages by processing output files generated by BTT systems.
Localized Corrosion in Alloy Steel of Steam Turbines
Authors: Cerny Miroslav
Published: February 2016

The development of effective localized corrosion damage prediction methods is essential for the successful avoidance of unscheduled downtime in steam turbines. It is reported that damage in steam turbines initiates in highly localized areas, most commonly at corrosion pits that act as stress raisers. Therefore, the evaluation of pits distribution and depth is necessary.
Effect of Thermal Loading on Stresses in Defective Surface Layer of Ceramics
Authors: Kuzin Valery V. , Grigoriev S.N. , Portnoy Mike
Published: February 2016

The typical defect based on the experimental study of the ceramic surfaces was defined. Finite element numerical model was used to compute stresses which develop in the ceramic surface layer with single typical defect under the action of thermal loading. The relationship between heat flow and stresses in the defective surface layer of oxide ceramics is identified.
Impact of Increased Temperature on Cohesiveness of Textile Glass Reinforcement with UHPC Matrix
Authors: Bittner Tomáš , Čech Jindřich , Bouška Petr , Vokáč Miroslav , Nenadálová Šárka
Published: February 2016

The contribution is focused on research results of thin elements with UHPC matrix reinforced by textile glass reinforcement. A set of three test samples with size of 1100 x 120 x 20 mm were produced in laboratories of the Klokner Institute. Using accompanying tests the material characteristics of the concrete matrix and the textile glass reinforcement were determined. This reinforcement is modified by a protective epoxy surface layer, co called coating. The reason of the coating is to prevent a formation and a development of corrosive processes on the reinforcement texture. The samples were tested at four-point bend test in a thermal chamber. The thermal chamber is a space where it is possible to gradually regulate the temperature up to 75 °C under a constant value of a loading. In the course of the temperature increasing is using a measuring unit measured mainly bend in the middle of the span in time and the course of an inner and outer temperature. The impact of the increased temperature on the cohesiveness of the non-conventional reinforcement and the UHPC matrix is evaluated from the monitored data.
Pulse Method Used for Non-Destructive Assessment of Glued Laminated Timber Beams
Authors: Klapálek Pavel , Melzerová Lenka , Plachy Tomáš
Published: February 2016

This text is focused on GLULAM (glued laminated timber) beams and determination of their properties. This text is mainly focused just on part of more complex research of glued laminated timber beams. This text is focused on pulse method, which is used to determine the dynamic modulus of elasticity of GLULAM beams. This text will describe how the pulse method works, with basic description, describes the tested material and compare the results of testing. In the conclusion we discuss the results, make conclusions and describe the way of our further research of glued laminated timber beams.
CFRP Strengthening of Damaged Stone Masonry Column
Authors: Kubat Jan
Published: February 2016

The paper deals with the effectiveness of CFRP confinement externally bonded on the surface of damaged stone masonry columns. The experimental measurement carried out within the DF12P01OVV037 research project [1] includes the mechanical behavior, specimen´s strength and failure modes. The results showed that the CFRP confinement may be considered as an effective stabilization technique able to increase the structural safety of damaged stone columns.
The Development of the Fine-Aggregate Concrete Strength with Recycled Cement Powder
Authors: Pavlů Tereza , Šefflová Magdaléna
Published: February 2016

This investigation was focused on possibility of use recycled cement powder originating from the construction and demolition concrete waste as partial replacement of cement in concrete mixture. The main goal of this paper is the study of the mechanical properties development of the fine-aggregate concrete with partial cement replacement at the age 7, 14 and 28 days. The compressive strength and dynamic modulus of elasticity were tested in time. The recycled cement powder from fine recycled concrete, which was used as partial replacement of cement, had the same grain size as cement. The concrete mixtures contained 95 %, 90 % and 85 % of cement and residue has been replaced by recycled cement powder. Mechanical properties were tested on cubic and prismatic specimens.
Experimental Verification of Demountable Precast Column System
Authors: Polák Aleš
Published: February 2016

Relocation of existing concrete structures requires full or partial demolition, which consumes a lot of energy and thus has a negative impact on the environment. From environmental point of view, demountable precast structures are sustainable. They allow “recycling” to the level of precast elements and so they save significant amounts of energy and materials. Another advantage of these structures is quick assembly without wet processes. A characteristic component of precast reinforced concrete construction system for multi-storey buildings are demountable joints of load-bearing precast reinforced concrete elements. This paper is focused on experimental verification of demountable precast column structure and its demountable steel joints. The experimental research was carried out within TA02010837 “Multipurpose dismantleable prefabricated reinforced concrete building system with controlled joint properties and possibility of repeated use”.
Components of Fracture Response of Steel Fibre Reinforced Concrete Specimens
Authors: Havlíková Ivana , Frantík Petr , Schmid Pavel , Šimonová Hana , Veselý Václav , Abdulrahman Alaa , Keršner Zbyněk
Published: February 2016

Records of fracture tests on steel fibre reinforced concrete notched specimens in a three-point bending configuration are evaluated in detail and selected results are discussed in the paper. The values of fracture parameters are determined using work of fracture method and double-K fracture model. Primarily, the role of plain concrete as a matrix in steel fibre reinforced concrete specimens is studied with regard to the recorded fracture response.
Compressive Strength of Lime-Based Mortars Reinforced by Micro Glass Fibers
Authors: Trejbal Jan , Kopecký Lubomír , Potocký Štěpán
Published: February 2016

Glass fiber-reinforced lime-based mortars have been studied. Two different fiber reinforcement amounts were used as an addition to the mixtures. Compressive strength and post-cracking behavior of mortars were observed and compared with reference mixture without any reinforcement (marked R). The fibers were added in the amount of 1.8 kg/m3 (mortar samples MA) and 93.75 kg/m3 (mortar samples MB). Destructive compression tests were chosen to compare the performance of the individual mixtures. The maximum compressive strength reached during the testing was the highest for reference samples, while those samples together with MA exhibited the elastic-brittle behavior. Only MB had post-linear hardening behavior and after reaching the maximum compressive strength a slow softening was present.
Evaluation of the Railway Substructure in the Turnout with the Movable Frog by Help of Decomposition
Authors: Pazdera Lubos , Smutny Jaroslav
Published: February 2016

The aim of the paper is focused on the analysis of the stress measurement in the railway substructure in the turnout with the movable frog prototype designed for a high speed. The evaluations were compared the measurement and the results obtained with theoretical presumptions. The Discrete Wavelet Transformation for the decomposition of the stress measurement and its evaluation is described. Two sections in the turnout with the movable frog were used for the measurement and signal analysis.
Measurement of Volume Changes of High Performance Cement Based Composites
Authors: Kolář Karel , Litoš Jiří , Bažantová Zdeňka , Reiterman Pavel
Published: February 2016

Performed research work is focused on the experimental determination of volume changes of high-performance concrete. Studied topic is an essential problem of all cement based composites because of its influence to mechanical and durability properties due to crack formation. Special high-performance cement based mortars are often used for quick rehabilitation and renovation of current concrete structures where minimal level of total volume changes is required. Interpretation of final results is highly dependent on the way of measuring, as it is documented in the present experimental program.
Cement Composite Reinforced with Synthetic Fibers: Comparison of Three-Point and Four-Point Bending Test Results
Authors: Topič Jaroslav , Bartoš Jan , Kopecký Lubomír , Šeps Karel , Prošek Zdeněk , Trejbal Jan
Published: February 2016

Presented article deals with the influence of PET fiber production on the bending strength of cement-based composite when incorporated into the fresh mortar, and comparison of results of 3-point and 4-point bending test. Cement paste samples were reinforced with 2 wt. % of primary or recycled PET fibers. The bending test was performed on prismatic samples with dimension of 40 × 40 × 160 mm. It was found that samples with recycled PET fibers, compared to primary ones, exhibit a decrease in bending strength. In the case of 4-point bending tests, the samples with recycled PET fibers exhibited higher bending strength than reference samples without any fibers. However, in the case of 3-point bending tests, the samples with recycled PET fibers had lower bending strength than the reference ones. The results suggest that recycled PET fibers could be used as an alternative to reinforce cement-based composites.
Micromechanical Analysis of Dental Implants and their Surface Modification
Authors: Jíra Aleš , Denk František
Published: February 2016

The submitted experimental analysis identifies, defines and compares the micromechanical properties of peripheral and supporting layers of intraosseous parts of dental implants through a nanoindentation method. The aim of the micromechanical tests is determination of elastic modulus and hardness. Investigated implants are characterized by the cylindrical shanks with surface plasma modification by hydroxyapatit. From the evaluated results it is evident that elastic modulus of peripheral layers of the compared samples ranges from 17 GPa to 157 GPa. The submitted work also includes a detailed microscopic analysis of surface morphology and chemical composition.
The Simulation of Collision of Standing Passenger with Rigid and Deformable Floor
Authors: Spirk Stanislav
Published: February 2016

The collision of standing passenger with floor is solved during rail vehicle emergency braking. The fall is serious type of passenger accident. For this purpose the model of rail vehicles interiors floor is created. The simulated behavior of passenger impact can predict useful information for experimental validation of floor properties.
Inflation Test of Developed Biological Composite Reinforced by Polyester Mesh
Authors: Veselý Jan , Chlup Hynek , Krajíček Milan , Žitný Rudolf
Published: February 2016

The inflation-extension tests were performed with developed hybrid composite manufactured from biological collagenous matrix and reinforced with polyester mesh. One sample was made without the mesh. This control specimen showed compliant and almost linear behavior. Tests of samples with integrated mesh in the matrix demonstrated that mechanical properties of final composite could be modulated by placing of its reinforced component in the matrix. It was shown that we can obtain response from stiff and linear to nonlinear and very compliant depending on the position of the mesh within biological matter.
Experimental Analysis of Planetary Transmission Load Sharing
Authors: Berka Ondřej , Dub Martin , Lopot František , Dynybyl Vojtěch
Published: February 2016

This paper is focused on determination of load sharing in planetary transmission during the test and usual operation. Load sharing is one of examined items in transmission. That is investigation of power flow uniformity through satellites in planetary transmission.
Enhanced Frequency Response Function Technique as Tool for Mode Separation in Experimental Modal Analysis
Authors: Huňady Róbert , Hagara Martin
Published: February 2016

The paper deals with mode separation process in experimental modal analysis. The main role in this process plays a technique known as Enhanced Frequency Response Function (EFRF), which allows separate the different modes of a structure. The results of the separation are responses of isolated systems with one degree of freedom by means of which complex poles can be estimated with greater accuracy. The paper describes the basic principle of EFRF technique and also presents its application in experimental modal analysis.
Experimental Analysis and Optimization of Vibrations of a Clamping Device by Using Hyperelastic Elements
Authors: Petrů Michal , Kovář Radovan , Martinec Tomáš , Srb Pavel , Lufinka Aleš , Kulhavý Petr
Published: February 2016

Nowadays composite frames can be used, for its specific properties, in many fields of industry. Lightweight composite frames can be significant structural components in some transportations, flights and military applications. The main problem is how to use automatic applications for winding filaments of the carbon fibres on a closed spatial shaped core of product frames, that has been still doing by the hand manufacturing. For automatic production could be used unique prototype of robotic technology, which allows winding of the carbon fibres on closed shape into the core of a frame. The biggest problem of the clamping device, used for the closed frames, are their vibrations and resonance caused due to the rotary motions. The vibrations and resonance negatively affect the process of carbon fibres winding. Experimental measurements were carried out to determine the acceleration on individual arms of the clamping device, which reaches to 2.5±0.6 g. Minimizing of the vibration was performed by a hyperelastic elements which reduce vibrations to 0.4±0.15g.
A chamber study of the influence of boreal BVOC emissions and sulfuric acid on nanoparticle formation rates at ambient concentrations
Authors: Dal Maso M. , Liao L. , Wildt J. , Kiendler-Scharr A. , Kleist E. , Tillmann R. , Sipilä M. , Hakala J. , Lehtipalo K. , Ehn M. , Kerminen V.-M. , Kulmala M. , Worsnop D. , Mentel T.
Published: February 2016

Abstract. Aerosol formation from biogenic and anthropogenic precursor trace gases in continental background areas affects climate via altering the amount of available cloud condensation nuclei. Significant uncertainty still exists regarding the agents controlling the formation of aerosol nanoparticles. We have performed experiments in the Jülich plant–atmosphere simulation chamber with instrumentation for the detection of sulfuric acid and nanoparticles, and present the first simultaneous chamber observations of nanoparticles, sulfuric acid, and realistic levels and mixtures of biogenic volatile compounds (BVOCs). We present direct laboratory observations of nanoparticle formation from sulfuric acid and realistic BVOC precursor vapour mixtures performed at atmospherically relevant concentration levels. We directly measured particle formation rates separately from particle growth rates. From this, we established that in our experiments, the formation rate was proportional to the product of sulfuric acid and biogenic VOC emission strength. The formation rates were consistent with a mechanism in which nucleating BVOC oxidation products are rapidly formed and activate with sulfuric acid. The growth rate of nanoparticles immediately after birth was best correlated with estimated products resulting from BVOC ozonolysis.
Improved analysis of solar signals for differential reflectivity monitoring
Authors: Huuskonen Asko , Kurri Mikko , Holleman Iwan
Published: February 2016

Abstract. The method for the daily monitoring of the differential reflectivity bias for polarimetric weather radars is developed. Improved quality control is applied to the solar signals detected during the operational scanning of the radar which removes efficiently rain and clutter contamination occurring in the solar hits. The simultaneous reflectivity data are used as a proxy to determine which data points are to be removed. A number of analysis methods are compared, and methods based on surface fitting are found superior to simple averaging. A separate fit to the reflectivity of the horizontal and vertical polarization channels is recommended, because it provides in addition to the differential reflectivity the pointing difference of the polarization channels, the squint angle. Data from the Finnish weather radar network shows that the squint angles are less than 0.02° and that the differential reflectivity bias is stable and determined to better than 0.04 dB. The results are compared to those from measurements at vertical incidence, which allows to determine the differential receiver bias and the transmitter bias.
In situ characterization of mixed phase clouds using the Small Ice Detector and the Particle Phase Discriminator
Authors: Vochezer P. , Järvinen E. , Wagner R. , Kupiszewski P. , Leisner T. , Schnaiter M.
Published: February 2016

Abstract. Mixed phase clouds (MPCs) represent a great source of uncertainty for both climate predictions and weather forecasts. In particular, there is still a lack of understanding on how ice forms in these clouds. In this work we present a technique to analyze in situ measurements of MPCs performed with the latest instruments from the Small Ice Detector family. These instruments record high-resolution scattering patterns of individual small cloud particles. For the analysis of the scattering patterns we developed an algorithm that can discriminate the phase of the cloud particles. In the case of a droplet, a Mie solution is fitted to the recorded pattern and the size of the corresponding particle is obtained, which allows for a size calibration of the instrument. In the case of an ice particle, its shape is deduced from the scattering pattern. We apply our data analysis method to measurements from three distinct MPC types. The results from laboratory measurements demonstrate that our technique can discriminate between droplets and ice particles in the same optical size range. This ability was verified by measurements at a mountain top station where we found an alternation of liquid- and ice-dominated cloud regions. The analysis of results from aircraft-based measurements illustrates the ice detection threshold of the technique.