Optical microscopes are typically designed as versatile tools that are capable of imaging at various modalities with different resolutions in respective
visual fields. A large extend of versatility causes increased complexity, size, and the cost. Imaging of tissue sections is a routine procedure in clinics and
research laboratories. Tissue staining consumables, required time for staining along with the cost of the imaging systems are the limiting factors for
widespread use. A multimode imaging system with enhanced resolution performance and automation is generally superfluous for the coarse resolution
imaging of tissue sections. A dedicated system for label free tissue section imaging is presented. Label free imaging with high contrast is provided in form
of quantitative phase. Earlier demonstrations of quantitative phase imaging of tissue sections utilized modified microscopes with different modalities
for correlated imaging and motorized stages for field enlargement. Here, the system follows an off-axis digital holographic imaging configuration for the
acquisition of quantitative phase at single shot. The system compromises from the resolution and magnification of a traditional microscope for the size
of visual field, ease of use, and relative cost due to the exclusion of sample stages. A software level stitching further enlarges the effective field of view.
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Lightning continues to possess threats to the reliable supply of electrical energy by causing damages to electrical equipment. Lightning transient
causes outages either by directly hitting electrical equipment or by the electromagnetic interference induced by it upon hitting the ground near to the
equipment. An electrical equipment which is witnessing a rise in application over the years are the insulated power cables. Use of these cables are not
only confined to transferring electrical energy over distances but they are also used as transformer winding in a type of transformer pioneered by ABB
called powerformers. Using XLPE insulated power cables as a case in point, the present study seeks to unravel the trajectory of research undertaken so
far in this area of transient behaviour of insulated power cables against lightning transients. In particular, attention has been focused on the response
of insulated power cables against non-standard lightning transient voltage waveforms. This review brings to the light that while transients response
against standard 1.2/50 µs lightning waveform is relatively well studied but more work needs to be further undertaken to fully appreciate the behaviour
of insulted power cables against the non-standard lightning transient waveforms which are more prevalent in actual field.
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A loop distribution system is mostly preferred in the distribution network rather than the radial one for reliable power and satisfaction of the customers
with comparably less power loss. This paper proposes a method to achieve line loss minimization by installing a “Sen” Transformer (ST) in a loop
distribution system. An ST works as a series voltage regulator or impedance regulator in the loop distribution system to address power quality issues with
better economic impact by inserting the compensating voltage or virtual impedance in the line. In the present work, the use of an ST is proposed in the
loop distribution system with two different control schemes for balanced power flow with a reduction in line loss. The total minimization in line loss can
be obtained if the summation of the all voltage drop across the line inductor in the loop distribution system tends to be zero. The total reduction in line
loss can be realized by installing the ST in the line that eliminates the circulating current by injecting the compensating voltage. Validation of the present
work has been done by the simulating loop distribution system with an ST and the loop current is eliminated to address the line loss minimization
problem with two different control schemes, line voltage compensation scheme (LVCS) and line inductance compensation scheme (LICS).
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This study presents a nonlinear observer that estimates structured and unstructured uncertainties based on a control methodology that is an adaptive
backstepping sliding mode controller to aim wheel slip tracking of a car-like robot. In the vehicle system, the scaling factor for the lengthwise force between
tire and road contact is considered as unknown, then adaptation law with Lyapunov-based analysis is derived for the unknown parameter. The lump
uncertainties estimated values that are estimated by the nonlinear disturbance observer and the scaling factor estimated values are directly applied in the
control input. The closed-loop system stability under the proposed controller is proven using Lyapunov’s stability analysis. Then, the adaptive backstepping
sliding mode controller's performance with the nonlinear disturbance observer is verified through simulations by comparing to the neural network (radial
basis function) observer, which is estimated as the lump uncertainties on quarter-vehicle dynamics
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In this study, a novel resonance-based single-switch and single-stage power factor correction (PFC) converter is proposed. This converter achieves soft
switching (SS), thereby minimizing switching losses. The converter draws current from the line in a sinusoidal form during each switching period, which
provides high PFC with decreased electromagnetic interference. Furthermore, the proposed converter transfers most of the input energy directly to the
output, providing direct power transfer with high efficiency using a forward-flyback converter. The rest of the input energy is transferred to the output via a
flyback converter to obtain high output regulation. At this converter, PFC circuit, forward and flyback converters share only one switch. The theoretical analysis
of this resonance-based single-switch and single-stage PFC converter is verified by a prototype output of 200 W/120 V with a 100-kHz switching frequency
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In this paper, we propose and investigate two types of algorithms for improving energy efficiency in wireless sensor networks. Clustering sensors in
wireless sensor networks is considered an effective approach to prolonging network lifetime. In this paper, we divide the study area into clusters at
30-m2 intervals. In each cluster, the sensor that is the closest to the cluster center and has the highest residual energy is selected as the cluster head. In
addition, a mobile sink is used to reduce the energy consumption of the cluster heads. The mobile sink travels to all clusters starting with the nearest
cluster and collects data from the cluster heads. In the first model, cluster head selection is performed and the mobile sink route is calculated using a
greedy approach. In the second model, cluster head selection is performed using an artificial neural network, and the mobile sink route is calculated
using a greedy approach. We compared our models with the energy-efficient scalable routing algorithm by the first node dies parameter, all nodes die,
and the residual energy of the network for each round condition. The simulation results demonstrated that the proposed models improved the energy
efficiency and extended the network lifetime
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The authors use goniophotometer to experimentally measure the light flux distribution of a wall-mounted luminaire with a luminous light bulb, a
direct-replacement light-emitting diode (LED) lamp, and a three-dimensional LED module with a heat pipe-based cooling system. The change dynamics
of integral characteristics of the light flux is determined. The stabilized light flux for different types of light sources at different power supply voltages
is measured. The obtained experimental data are used to calculate the luminous efficacy of the luminaire with the direct-replacement lamps and to
determine its dependence on the supply voltage. The thermal conditions for using LEDs in direct-replacement lamps and in lamps with an original
cooling system based on heat pipes are also determined.
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This paper investigates a chaotic communication system based on the combination of high-efficiency differential-chaos-shift-keying (HEDCSK) scheme
and multiple-input multiple-output technique, which aims at exploiting multi-path propagation to improve the system performance. Operation and
discrete model of the system with the use of modulation/demodulation of HEDCSK and Alamouti space-time coding/decoding for 2×2 antennas are
described. The bit error rate (BER) in the presence of an additive white Gaussian noise (AWGN) and Rayleigh fading is theoretically analyzed and verified
by numerical simulations. Obtained results show the improvement of the BER performance of the proposed scheme compared to other related systems
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This study proposes a new energy-efficient and high data-rated communication technique by combining media-based modulation (MBM) and
differential chaos shift keying technique (DCSK), called DCSK–MBM. The MBM technique, which forms the infrastructure of this proposed system, is one of
the newest members of the index modulation family, while DCSK offers considerable performance improvements for fading channels. Communication
comprises two stages in the DCSK system. In the first stage, only the reference symbol is transmitted to the receiver side, whereas in the second
stage, information is carried along with the reference symbol. The negative aspect of this method is that it reduces both transmission data rate and
spectral efficiency. The MBM technique provides a significant increase in both spectral efficiency and data rate because it performs index modulation
with reconfigurable antennas and transmits extra information bits. To minimize the disadvantages of the DCSK technique and create a more energyefficient and high data-rated technique, the MBM technique is combined with the DCSK technique. Thus, considerable progress is made. All performance
analyses are performed over Rayleigh fading channels for M-ary phase shift keying/quadrature amplitude modulation
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A broadband-slotted ring/lumped resistor-based metamaterial absorber (MA) is presented in this study for Ku
-band microwave applications. Numerical
results of the MA indicate that it can achieve a broadband absorption ratio of more than 85% in the frequency range of 12.4–17.6 GHz and has active
polarization insensitivity and wide incidence-angle response over the entire operation band between 12.4-17.6 GHz. The designed MA is ultrathin
around λ/14.7 in terms of wavelength at its lowest operation frequency, corresponding to 1.7 mm. The proposed unit-cell structure of the MA is novel,
consisting of a slotted ring with eight symmetrically-located lumped resistors, FR-4 material, and a metallic ground, which is compatible with low-cost
PCB fabrication; therefore, the MA is suitable for practical microwave applications in the Ku
-band
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