Miracle-dz/UniFAR-FTUs huggingface dataset:
A study of some frameworks used by pupils aged 11 to 13 years in the interpretation of air pressure

Summaries English When children interpret experiments concerning the physical properties of gases, they generally use frameworks from the field of mechanics. In reality, these experiments give them the opportunity of expressing relationships between movement, equilibrium and mechanical dimensions, such as forces. In their experimental interpretations, children aged 11 to 13 years emphasize in most cases those stages of an experiment which involve movement: movement as a cause of pressure change of a gas, and movement as the effect of this pressure change. This leads them to express frameworks which have been similarly observed by Piaget and other authors. For example, movement of air in one direction is thought to cause or to be caused by a specific force in one direction; similarly, the state of equilibrium and thus the immobility at the end of the experiment, are characterized by an absence of forces. The interpretations of several experiments relating to air pressure are analysed using the commentaries.
Mechanism of sound production by the Chinese grasshopper Acrida cinerea (Orthoptera: Acrididae) during flight

Many species of grasshoppers in subfamilies Oedipodinae, Gomphocerinae and Acridinae make sounds when they escape by flying. We carried out four kinds of experiments with the Chinese grasshopper, Acrida cinerea (Orthoptera: Acrididae: Acridinae), whose males often make sounds while flying, to examine the mechanism of sound production during flight by grasshoppers. First, we recorded high‐speed video and audio of the tethered flight of the males and found that they produced sounds when they clapped their hindwings together at the end of the upstroke. Second, we recorded the tethered flights of the males when we prevented them from clapping their hindwings to clarify whether the hindwing clapping produced the sounds, and we found that the obstruction of clapping hindwings prevented sound production by the males. Third, we recorded the free flight of the males and determined whether the sound produced by clapping hindwings was not specific to the tethered condition. The males clapped their hindwings during free flight, and sounds were produced when they clapped their hindwings. Finally, we observed the tethered and free flights of the females because the possibility of crepitation flight by the females existed, and we found that sound was produced by females clapping their hindwings during flight. These results showed that male A. cinerea make sounds during flight by clapping their hindwings, and females also have the ability to make sounds by using the same mechanism. This study provides the first experimental evidence on the mechanism of sound production during flight through observing the behaviors of grasshoppers.
Case Studies of Leak Detection and Location in Water Pipe Systems by Inverse Transient Analysis

The current paper aims at the assessment of the effectiveness of a popular transient-based technique—inverse transient analysis (ITA)—for leak detection in water pipe systems using physical data. Data were collected from two pipe systems made of polyethylene: a laboratory facility at Imperial College London and a quasi-field system at Thames Water Utilities. A hydraulic transient solver especially developed for viscoelastic pipes (typically made of polyethylene) and an optimization algorithm for the simultaneous creep calibration and leak location have been developed for the application of this technique. The evaluation of the presence, location, and size of leaks was carried out using collected data. ITA allowed for the identification of the approximate location of leaks as long as the physical characteristics of the pipeline are well known, the transient is generated by a fast change of flow conditions, the leak has a “reasonable size,” and the transient solver is accurate enough to describe the transie.
Sliding Mode Control Scheme for Tele-Operation Manipulator

Master and slave manipulator has been widely used because it can work easily in the working environment where the human beings can hardly work. In order to make the manipulator control system have good tracking performance, a control strategy based on sliding mode control was proposed for master-slave manipulator control system. Considering that the quality and stability of servo system will be affected by the chattering phenomenon in the SMC, a reaching law approach was used to reduce the chattering phenomenon. The proposed control strategy can make the master and slave manipulator have good performances on force and position tracking, and the chattering problem has also been alleviated. Simulation and experiments results show that the proposed control strategy can produce good performances on the force and position tracking, the problem of chattering has also been inhibited significantly, and the stability and quality of the master and slave manipulator has been improved as well.
Protective effects of endothelial progenitor cell microvesicles on Ang II-induced rat kidney cell injury

Chronic hypertension can lead to kidney damage, known as hypertensive nephropathy or hypertensive nephrosclerosis. Further understanding of the molecular mechanisms via which hypertensive nephropathy develops is essential for effective diagnosis and treatment. The present study investigated the mechanisms by which endothelial progenitor cells (EPCs) repair primary rat kidney cells (PRKs). ELISA, Cell Counting Kit-8 and flow cytometry assays were used to analyze the effects of EPCs or EPC-MVs on the oxidative stress, inflammation, cell proliferation, apoptosis and cycle of PRKs induced by AngII. A PRK injury model was established using angiotensin II (Ang II). After Ang II induction, PRK proliferation was decreased, apoptosis was increased and the cell cycle was blocked at the G1 phase before entering the S phase. It was found that the levels of reactive oxygen species and malondialdehyde were increased, while the levels of glutathione peroxidase and superoxide dismutase were decreased. Moreover, the levels of the inflammatory cytokines IL-1β, IL-6 and TNF-α were significantly increased. Thus, Ang II damaged PRKs by stimulating oxidative stress and promoting the inflammatory response. However, when PRKs were co-cultured with EPCs, the damage induced by Ang II was significantly reduced. The current study collected the microvesicles (MVs) secreted by EPCs and co-cultured them with Ang II-induced PRKs, and identified that EPC-MVs retained their protective effect on PRKs. In conclusion, EPCs protect PRKs from Ang II-induced damage via secreted MVs.
A numerical approach for the static analysis of the body of pressurized dry gas holders

In this paper, a numerical method is developed to calculate deformations and stresses of the body of dry gas holders under gas pressure. The deformations of the wall plates are decomposed into out-of-plane bending and in-plane deformation. The out-of-plane bending of the wall plates is described by the theory of orthotropic plates and the in-plane deformation by the biharmonic equation of flat plates under plane stress. The theories of beam columns and beams are employed to analyze the columns and corridors, respectively. By considering compatibility conditions between the members and boundary conditions, equations for the determination of deformations and stresses of dry gas holders under gas pressure are obtained. Both the proposed approach and the finite element method are used to investigate the deformations and stresses of the body of a dry gas holder under gas pressure. The results from the proposed method agree with those from the finite element method. Because far fewer unknowns are involved, the .
Design and Development of a Nine Stage Axial Flow Compressor for Industrial Gas Turbines

A nine stage industrial axial flow compressor with a pressure ratio of 9.1:1 was designed, built and rig tested. The modern technology and design tools developed by government/aircraft engine compressor technologists were used for an industrial gas turbine application. The compressor was designed with “arbitrary” airfoil blading including CFD analysis in all blade rows. Flowpath contouring in the hub region of the rotors was used to decrease losses. The compressor rig was tested at the Compressor Research Facility at Wright Patterson Air Force Base in Dayton, Ohio. Extensive testing included determining the impact of stator leading edge instrumentation on performance. The compressor demonstrated excellent efficiency and stall margin in its first build. This paper describes the aerodynamic design, test instrumentation and test results.Copyright © 1998 by ASME
Filament Development for Laser Assisted FFF 3D Printing

The aim of this paper was to develop filaments which can be used for laser assisted fused filament fabrication (FFF) 3D printing in order to increase the inter-layer bonding strength of the printed part. The filaments were developed from the most commonly used filament materials, acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) with the addition of different polymer additives. After performing near infrared (NIR) absorption tests, graphite was selected for further development as it possesses excellent NIR absorption capabilities whilst resulting in consistent filaments’ diameter and being economically viable. A conventional FFF 3D printer was initially used to test the printability of the developed filaments. Afterwards, a fiber couple laser diode was integrated within the printing head to heat up the previously extruded layer. The produced filaments were used to 3D print specimens for shear and tensile testing. With the laser heating, an increase of 14.5% in the elastic modulus and an increase of 27.8% in the tensile strength of the printed parts were noticed. This showed that adding additives into filament materials for localized laser heating is an effective method of increasing the inter-layer bonding, and therefore, the overall strength and durability of FFF 3D printed parts.
Low frequency electromagnetic signals from underground explosions: On-site inspections research progress report

We are investigating the characteristics of extremely low frequency (ELF) electromagnetic pulse (EMW) phenomena from underground nuclear and chemical explosions and from surface chemical explosions as they may be applied in an On-Site Inspection (OSI) context under a Comprehensive Test-Ban Treaty (CTBT). The principal application of these phenomena is for discrimination among underground chemical explosions, underground nuclear explosions, and earthquakes. Underground chemical and nuclear explosions both generate low-frequency EMP signals (about 1 Hz) that are observable within several kilometers of ground zero. During this fiscal year we have been gathering data from explosions of opportunity to see if ELF EMP signals are observable from large ripple-fired blasts and from smaller dedicated explosions such as those occurring at the NTS. In addition, we are continuing to review data from the Henderson Mine deployment that took place during FY94 and data from previous underground nuclear tests including Hunter`s Trophy and past underground nuclear tests have been analyzed and we here make estimates of the properties of the EMP ftom underground nuclear ard chemical explosions, including detectability, dependence on yield, and dependence on distance from the source. Data from the Henderson Mine provide information about detection of EMP from typical moderate size underground chemical explosions in hard rock and problems related to detection of EMP in a mine environment located at high elevations. Data from the Carlin Mine site provide information about EMP from surface ripple-fired chemical explosions and detection in an open-pit mine environment. Data from the Kuchen experiment at NTS provide additional data about small underground chemical explosions in a setting similar to that for underground nuclear tests at the NTS.
Cryo-EM Map of the CFA/I Pilus Rod

Enterotoxigenic Escherichia coli (ETEC) are common agents of diarrhea for travelers and a major cause of mortality in children in developing countries. To attach to intestinal cells ETEC express colonization factors, among them CFA/I, which are the most prevalent factors and are the archetypical representative of Class 5 pili. Due to their helical quaternary structure that can be unwound and works as a damper of force, CFA/I pili help ETEC bacteria withstand intestinal fluid motion. We report in this work the CFA/I pilus structure at 4.0 Å resolution and report details of the donor strand complementation. The density map allows us to identify the buried surface area between subunits, and these regions are correlated to quaternary structural stability in class 5 and Chaperone-Usher pili. In addition, from the EM map we also predicted that residue 13 (proline) of the N-terminal β-strand could have a major impact on the filament’s structural stability. Therefore, we used optical tweezers to measure and compare the stability of the quaternary structure of wild type CFA/I and point-mutated CFA/I in which proline 13 was changed to a non-polar residue, phenylalanine. We found that pili with this mutated CFA/I require a lower force to unwind, supporting our hypothesis that Pro 13 is important for structural stability. The high-resolution CFA/I pilus structure presented in this work and the analysis of structural stability will be useful for the development of novel antimicrobial drugs that target the pilus structure to reduce its damping properties, which are needed for initial attachment and sustained adhesion of ETEC. Synopsis The structure of a common virulence factor expressed on the surface of diarrheacausing bacteria, CFA/I pili, has been determined at 4.0 Å resolution. The role of proline 13 in stabilizing the pilus structure has been confirmed using force-measuring optical tweezers on wild type and point-mutated pili.
Multiobjective optimal controller design with genetic algorithms

Finding a controller for a given plant in order to achieve a number of design objectives is a common control design problem. As well as closed loop plant stability, design objectives often include measures such as rise time, settling time, overshoot, asymptotic tracking, decoupling and regulation, gain and phase margins, small disturbance response and bounds on frequency response magnitudes. Genetic algorithms have previously been shown to be useful in addressing ill-behaved optimization problems, being able to cope with discontinuities, multimodality and uncertain function evaluations, and their single objective formulation has been extended by the authors to include multiple objectives. The paper shows how genetic search can be interactively used to design controllers of given complexity, in a multiobjective sense, while learning about the trade-off between the design objectives. >
Statistical design of experimental analysis of TiN films deposited by ion metal plasma PVD for sub-0.25-um IC process applications

A Vectra IMPTM (Ion Metal Plasma) source was used to deposit TiN films for application such as W plug liner and Al wetting layer. The process is based on conventional magnetron sputtering with the addition of a higher density, inductively coupled RF plasma between the sputtering cathode and the substrate. This new technology enables deposition of the films into deep submicron contacts with >50% bottom coverage. In addition to enhancing step coverage of metal films, such as Ti and TiN, this process also has significant effects on the materials properties of the films. The film properties of the TiN films were studied as a function of the fundamental process parameters, namely DC target power, RF coil power, and chamber process pressure, using statistical DOE technique. The study shows that a high degree of control over the film properties can be obtained in the IMP process.
On Jacobson â€“ Small Submodules

Let R be an associative ring with identity and let M be a unitary left Râ€“module. As a generalization of small submodule , we introduce Jacobsonâ€“small submodule (briefly Jâ€“small submodule ) . We state the main properties of Jâ€“small submodules and supplying examples and remarks for this concept . Several properties of these submodules are given . Also we introduce Jacobsonâ€“hollow modules ( briefly Jâ€“hollow ) . We give a characterization of Jâ€“hollow modules and gives conditions under which the direct sum of Jâ€“hollow modules is Jâ€“hollow . We define Jâ€“supplemented modules and some types of modules that are related to Jâ€“supplemented modules and introduce properties of this types of modules . Also we discuss the relation between them with examples and remarks are needed in our work.
Design of lowpass filter using a novel split‐ring resonator defected ground structure

A novel square split‐ring resonator (SRR) defected ground structure (DGS) cell model is presented and analyzed in detail. Then an improved SRR DGS cell model loaded with open stubs is proposed in order to enhance the out‐band suppression. Based on this structure, an S‐band microstrip lowpass filter with low in‐band loss and high out‐band suppression is designed and fabricated effectively. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 288–291, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22111
Developments in Assessing the Structural Integrity of Applied Surfaces to Concrete Buildings

Debonding, leading to the subsequent detachment of applied finishes to concrete buildings, is becoming a serious problem in many parts of the world. Checking building elevations by employing the technique of Infra‐red Thermography using a process developed by the writer can give advance warning of potential defects. This can enable early remedial action to be undertaken to repair a building surface before it becomes detached from the concrete substrate, possibly resulting in a hazard to passers‐by. The thermographic test method has been compared with other more traditionally used NDT methods including sounding, rebound hammer, and ultrasonic pulse velocity measurements. Although the thermographic equipment is initially more expensive, the surveying method can be shown to be faster and more accurate than any other technique currently available for this type of building evaluation.
LITSEA ANAMALAYANA (LAURACEAE) A NEW SPECIES FROM NELLIYAMPATHY HILLS, INDIA.

The new species Litsea anamalayana Robi & Udayan, from Kerala, India, is described and illustrated. A detailed description is given, together with information on its distribution and ecology. Photographs of the new species are provided, as well as a comparison with the morphologically similar L. glabrata (Wall. ex Nees) Hook.f.
Research on Attack Model for Cognitive Network Based on Scientific Analysis of Network Material System

Cognitive attacks, which influence the user’s perceptions and behavior, are more serious than physical or even syntactic attacks. We construct an attack model for cognitive Network based on scientific analysis of Network material system to visualize cognitive attack. The cognitive attack model consists of two parts: attackers and netizens. We formalize each element of the model. The cognitive attack example analysis illustrates the rationality of the model.
Ultimate Capacity of Doubler Plate–Reinforced Tubular Joints

To ensure structural integrity after modification and/or retrofitting, the behavior of strengthened tubular joints needs to be understood. The finite-element method is a useful tool for studying the problem. However, this numerical technique has to be verified by experimental results before being used extensively. In this paper, the ultimate capacity of doubler plate–reinforced tubular joints is studied. To establish a reference point, a doubler plate–reinforced tubular T-joint was fabricated, instrumented, and tested to failure under axial compression brace loading. The structural behaviors were observed and analyzed. It was found that the ultimate capacity was greatly improved by the inclusion of the doubler plate. The experimental load-displacement curves were compared with the finite-element predictions and good agreement was obtained. The finite-element techniques were then verified and could be used to study the ultimate capacity. A behavioral study was then conducted by applying various types of br.
The Design and Optimization of Nonwoven Composite Boards on Sound Absorption Performance

This study aims to investigate the optimal value of design parameters for the sound-absorbing nonwoven composite board. The number of laminated layers and thickness of polyester fiber are viewed as the design parameters for fabricating the nonwoven composite board. The 2D, 7D and 12D polyester fibers are individually mixed with 4D low-melting point polyester fiber to produce 2D polyester nonwoven fabric (2D-PETF), 7D polyester nonwoven fabric (7D-PETF) and 12D polyester nonwoven fabric (12D-PETF) respectively. The developed nonwoven fabrics are then used to fabricate 2D-PET, 7D-PET and 12D-PET nonwoven composite boards through the multiple needle-punching and thermal bonding techniques. The sound absorption performance of each PET composite board is carefully examined. The experimental results reveal that the 7D-PET composite board with 10 laminated layers has the optimal sound absorption performance.
An Experimental Platform Based on Transfer Learning Paradigm for Mobile Robots

The transfer learning paradigm promises to improve the adaptability of mobile robots which apply machine learning (ML) algorithms for perception and localization. An system framework based on transfer learning paradigm for mobile robots was proposed. The keys of the framework are 1) how to arrange the knowledge database, 2) how to select the source data, source model and priori knowledge, 3) the method to achieve the target model and 4) the method to gain new samples. An experimental platform was built up in order to gain data to verify the framework, whose underpan is the same as the Freescale Cup, MCUs core is ARM Cortex-M4, raw data is stored in a SD card and model is trained offline by a more powerful computer using ML algorithms. The MCU communicates with the powerful computer by Zigbee or WiFi. The experimental platform is cheap and feasible, which is validated by data collection and model training experiments.
Understanding the partial discharge activity of conducting particles in GIS under DC voltages using the UHF technique

The major cause of failure of DC-GIS is due to presence of foreign particles causing partial discharges in the insulation structure. The particle movement in gas insulated system (GIS) radiates electromagnetic waves and the bandwidth of the signal lies in the range 1–2 GHz. Increase in applied DC voltage/pressure has not altered the frequency content of the ultra high frequency (UHF) signal generated due to partial discharge formed by particle movement. The UHF sensor could recognize the breakdown of sulfur-hexa-fluoride (SF6) gas under DC and Lightning impulse voltages and the frequency content of the signal captured by the UHF sensor lies up to 500 MHz. Mounting UHF sensor in GIS could allow one to classify internal partial discharges from breakdown, at the time of testing/during operation. Copyright © 2009 John Wiley & Sons, Ltd.
An analysis of positive and negative resistance characteristics in the high-current-density region of Schottky diodes

A number of different diode characteristics are observed in small-area silicon Schottky diodes under forward-biased and high-current-density conditions. These characteristics, such as positive resistance, negative resistance, and normal diode characteristics, are analyzed. The analysis demonstrates that the variations are due to the minority-carrier accumulation in the epitaxial region of the diodes, which is mainly controlled by Schottky barrier heights and the resistivity of the semiconductor epitaxial region. >