Time correlation functions in classical liquids at high frequencies (${10}^{12}$ ${\mathrm{sec}}^{\ensuremath{-}1}$) and short wavelengths (${10}^{\ensuremath{-}8}$ cm) are analyzed using linear response theory of Martin Kadanoff. Rigorous expressions, based on dispersion relation, sum rules, limiting behavior long low frequencies, obtained terms damping (or memory) function. Specific assumptions regarding the function then enable numerical results to be which compared with computer...

Icephobic coatings have been extensively studied for decades to overcome the potential damage associated with ice formation in various devices that are operated under harsh weather conditions. Superhydrophobic surface applied icephobic coating applications owing their low energy. In this study, an of a self-formed superhydrophobic using polydimethylsiloxane (PDMS) and SiO2 powder was investigated. The effect superhydrophobicity on icephobicity determined by varying experimental parameters....

Abstract Ice accumulation and proliferation adversely affect the activities of various residential, commercial, polar research stations. Although significant efforts are devoted to preventing ice adhesion surfaces by developing anti‐icing coatings, it is still necessary enhance overall performance durability. Herein, a facile approach proposed for fabricating an icephobic coating on aluminum 6061 (Al) substrate, poly(dimethylsiloxane) (PDMS)/ poly(tetrafluoroethylene) (PTFE) composite...

We have developed an integrated strain array for cell culture enabling high-throughput mechano-transduction studies. Biocompatible chambers were with acrylic pneumatic compartment and microprocessor-based control system. Each element of the consists a deformable membrane supported by cylindrical pillar within well. For user-prescribed waveforms, annular region is pulled into well around under vacuum, causing pillar-supported cultured cells to be stretched biaxially. The optically clear...

The spectral distributions of light scattered under various polarization conditions in liquids composed optically anisotropic molecules are analyzed. Macroscopic equations derived using analogous electric circuits which simulate the viscoelastic behavior due to shear stress, reorientations, and coupling with internal degrees freedom. describe long-wavelength thermal fluctuations liquid form basis a unified calculation depolarized Brillouin scattering. Under condition that relaxation takes...

Unmanned aerial vehicles (UAVs), also known as drones, are a cost-effective alternative to traditional surveying methods, and they can be used collect geospatial data over inaccessible or hard-to-reach locations. UAV-integrated miniaturized remote sensing sensors such hyperspectral LiDAR sensors, which formerly operated on airborne spaceborne platforms, have recently been developed. Their accuracies still guaranteed when incorporating pieces of equipment ground control points (GCPs) field...

This paper details the development of a low-loss, PIN diode single-pole double-throw (SPDT) absorptive switch for an ultra-wideband radar. The fabricated operates with peak power 200 watts at 10% duty cycle. It has insertion loss less than 0.8 dB, return greater 19 and isolates transmitter receiver beyond 37 dB over frequency band (170 MHz-470 MHz) sensitive radar measurements. An external RF limiter low-power CMOS receiving end are used to reduce video leakage from enhance isolation up 80...

In this paper, we present a stretchable microelectrode array for studying cell behavior under mechanical strain. The electrode consists of gold-plated nail-head pins (250 µm tip diameter) or tungsten micro-wires (25.4 in inserted into polydimethylsiloxane (PDMS) platform × 25.4 mm2). Stretchable interconnects to the outside were provided by fusible indium-alloy-filled microchannels. alloy is liquid at room temperature, thus providing necessary stretchability and electrical conductivity. can...

Recently, there is a rising interest on studying bio-inspired robotic fish because of real fish's great maneuverability and high energy efficiency. However, the researches about have not been done so much are still lots problems to use them in environment such as river. This paper describes 'Ichthus' which developed KITECH has 3 DOF propulsive mechanism. We develop dynamic motion equation underwater analyze response characteristics according input parameters tail fin's amplitude oscillation...

Abstract This paper presents a novel high‐gain, miniaturized, and ultra‐wideband tapered‐slot Vivaldi antenna (TSVA) for ice‐sounding radar applications. To miniaturize the improve impedance matching gain of conventional TSVA, tapered slot edge, circular cavity, rectangular inner patch, slit structures are newly designed introduced. The simulation results show that size is reduced by 15% increases peak realized up to 5.1 dBi, compared antenna. optimized was fabricated characterized its...

AbstractAn experimental study is performed to investigate the natural convection heat transfer characteristics and solidification of molten metal pool concurrently with forced convective boiling overlying coolant simulate a severe accident in nuclear power plant. The relationship between Nusselt number (Nu) Rayleigh (Ra) region determined compared correlations literature data subcooled water. Given same Ra condition, present results for Nu liquid are found be higher than those predicted by...

This paper presents an overview of current electricity generation and consumption patterns in the Antarctic. Based on both previously published newly collected data, describes status renewable-energy use at research stations A more detailed view systems is also presented, demonstrating how different types resources may be used combined. The will serve as a guide to various technologies, highlighting well-established praxis, lessons learned, potential ideas for improvement. Several renewable...

Research activities in Antarctica face a number of risk factors, such as cold, strong winds, and isolated or dangerous environments. Among them, crevasses, which are deep cracks glaciers, can cause fatal accidents since they difficult to locate covered with snow. In this paper, we present the development, design, deployment an UGV (Unmanned Ground Vehicle) that explore ice-sheets be used various polar research fields. The developed was customized remotely detect crevasses prevent related...

The two-dimensional deformation of immiscible drop in simple shear flow was investigated using the front tracking method.Interface particles were traced by Runge-Kutta 2 nd order method and boundary immersed used for calculation surface tension force at global mesh.Isothermal, incompressible creeping assumed.The main purpose this research is to analyze effect viscosity ratio elasticity on deformation.Oldroyd-B model as a constitutive equation with stabilizing schemes such DEVSS-G/SUPG matrix...

This paper presents the design and development of a high-sensitivity ultra-wideband radar for sounding imaging 5-km thick polar ice. The is optimized to detect internal layers in ice from surface bed with fine resolution. consists 8 transmitters 16 receivers. Each transmit/receive module designed operate either as standalone system or channel multi-channel radar. subsystem optimized, then integrated. transmitter's output power 53 dBm operates over frequency band 170 - 470 MHz. A push-pull...

AbstractXenon spatial oscillation may give rise to operational difficulties in a nuclear power plant. In this study, order investigate xenon instability for pressurized water reactor, the frequency-domain technique is adopted by using generalized Nyquist criterion, which more general and suitable multi-input/multi-output system. Also linearized modal fluxes are obtained expansion. This model has been implemented test axial stability of KNU 7 unit with changes plant operating parameters.