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Is power zero-sum (relative gain/loss) or variable-sum (absolute gain/loss)? The response to this century-old puzzle depends on how power manifests itself during human interactions in diverse conte...

A two-element linear array of hybrid-fractal antennas has been reported in this paper. The center frequency (f r ) of the proposed element is 12.50 GHz, used for the direct broadcast satellite (DBS) application under Ku-band. The hybrid-fractal is derived by conjugately applying a scaling factor of 50% followed by 33.33% on regular circle geometry in its subsequent steps. The antenna gives a satisfactory parametric performance in time-domain analysis for both side-by-side and face-to-face arrangements. In order to achieve improved parametric results, a low level of loss, a high level of isolation between its output ports, and better bandwidth response, the Wilkinson power divider is incorporated to design the array’s feed network. The absolute gain of the antenna and the array are 11.17 and 13.48 dBi, respectively. Both antennas can provide 100% bandwidth coverage for DBS application and give a shallow x-pol level along the entire half-power beamwidth (HPBW)region. Both the antennas provide satisfactory electromagnetic compatibility performance.

We have proved the equivalence of the Kim method and the Omi method that are promising methods in single-cut near-field far-field transformations in spite of the different appearances [1] . The errors of the absolute gain patterns using those methods come from the deviations of the radiation parts from the center of the rotation in the measurements. In this paper, we propose an improved method to reduce the errors from about 1 dB to below 0.1 dB. In addition, the new method does not need to set the phase center of an antenna under test (AUT) at the center of a measurement turntable: this merit is of great value in real measurements for antennas such as Log-periodic dipole antennas (LPDA), of which phase centers are moving according to the measurement frequencies. The proposed method is based on the new Kim-Omi equation as

In late 2020 the U.S. Geological Survey (USGS) began the distribution of Landsat products associated with their collection 2 reprocessing of the archive. Several changes were implemented within the Landsat Product Generation System (LPGS) and the calibration parameters applied to the Landsat imagery for the collection 2 processing. When comparing between collection 1 and collection 2 products, radiometric and geometric differences will be present. One of the most substantial changes between the two collections was an adjustment to the ground control which made the control more accurate from an absolute and relative perspective. Some of the other changes associated with collection 2 processing were to the Digital Elevation Model (DEM) used in terrain correction, the Thermal Infrared Sensor (TIRS) relative gains, TIRS absolute calibration, Operational Land Imagery (OLI) absolute gain model, OLI relative gain, and OLI bias calculation to name a few. Although these changes also have an effect on the differences between the product associated with these two collections, the change in the ground control, although typically less than one 30-meter multispectral pixel in magnitude, will have the largest effect on the differences between the products. This change in ground control is also a spatially dynamic change that although is low in spatial frequency, is nonlinear and is not a change that can be modeled on a global or even on a local Worldwide Reference System-2 (WRS-2) path and row scale. The effects of these ground control changes will be discussed and demonstrated within this paper along with examples showing their effect on specific datasets. This paper demonstrates some of these geometric differences associated with the ground control through both the registration statistics created during product generation and through an example comparison of a set of collection 1 and collection 2 products.

A pseudo-background continuous-time strategy is developed for gain and offset calibration in open-loop inter-stage residue amplifiers of pipeline ADCs. The ping-pong calibration strategy is enhanced for loop gain and accuracy to be utilized for open-loop RAs. Thanks to a reliable technique for preserving analog voltages for long time durations, data conversion continuously proceeds. In addition, other advantages of the foreground techniques, like lower power consumption and smaller area are achieved. The reduction in power consumption due to the elimination of a wide-bit digital processor easily overcomes the increase which stems from the replica residue amplifier. Storing the calibration results in reliable analog storages, the multiplexing frequency and clock frequency within the calibration loop are reduced to 100 KHz, respectively, which result in a significant amount of power reduction. Monte-Carlo analysis for 100 iterations shows that the calibration loop provides an absolute gain of 4 with the median value of 3.996 and standard deviation of 0.003, while the threshold voltages and reference levels experience a Gaussian distribution with 25 mV variations at 3σ. Total power consumption equals 1.8 mW for both the offset and gain calibration at 1.8 V (and 3.3 V for DAC) supply voltage. More than 9-bit accuracy is obtained at 50 mV peak-to-peak residue. Linearity is reduced to 7-bits for full-swing input range. Also, 13 dB and 8 dB improvement in SNDR and SFDR of a 13-bit 100S/s pipeline ADC is achieved when the offset and gain calibration loops are activated. Post-Layout simulation results are presented at all process corners using the BSIM3v3 model of a 0.18 μm CMOS technology.

A novel design of S-band based circularly polarized small satellite patch antenna is presented. It comprises three slots and an overall dimensions of 98 mm x 98 mm. The antenna has been designed for an impedance of 50 ohm and shows optimum performance for frequency range of 2.3 GHz to 2.5 GHz. Absolute gain observed is 7.8 dBi with main lobe at 20 normal to the antenna plane, making it close to unidirectional antenna. A diamond shaped patch with suitable location of coaxial feed allows the antenna to be circular polarized. Additionally, three identical slots were embedded in the radiating patch to obtain the high bandwidth compact antenna with right circular polarization. The variation of feed position allows switching between Left and Right Hand Circular Polarization (LHCP, RHCP) with 5.48 dBi gain. The S11 parameter was measured using Network Analyzer and similar results were obtained as software simulation output. The designed antenna is compatible with CubeSat configuration and hence can be used for various small satellite applications.

Space-division multiplexing (SDM) attracts attention to cladding-pumped optical amplifiers, but they suffer from a low pump power conversion efficiency. To address this issue, ytterbium (Yb3+) and erbium (Er3+) co-doping is considered as an effective approach. However, it changes the gain profile of Er3+-doped fiber amplifiers and induces the gain difference between optical wavelengths in the C-band, significantly limiting the effective band of the dense wavelength-division multiplexed (DWDM) system. This paper is devoted to a detailed study of a cladding-pumped Er3+/Yb3+ co-doped fiber amplifier (EYDFA) through numerical simulations aiming to identify a configuration, before assembling a similar EYDFA in our laboratory premises that ensures the desired performance. The simulation model is based on a commercial double cladding EYDF whose parameters are experimentally extracted and fed to the EYDFA setup for the system-level studies. We investigate the wavelength dependence of the amplifier’s characteristics (absolute gain, gain uniformity, noise figure) and bit error rate (BER) performance for several DWDM channels and their optical power. The obtained results show that a 7 m long EYDF and co-propagating pump direction is preferable for the EYDFA with a 3 W pump source at 975 nm and with the given gain medium characteristics for WDM applications. For instance, it ensures a gain of 19.7–28.3 dB and a noise figure of 3.7–4.2 dB when amplifying 40 DWDM channels with the input power of −20 dBm per channel. Besides, we study EYDFA gain bandwidth and the maximum output power when operating close to the saturation regime and perform a sensitivity analysis showing how the doped fiber’s absorption and emission cross-sections impact the amplification process through energy transfer from Yb3+ to Er3+. Finally, we quantify the power penalty introduced by the EYDFA; the results show that it is not higher than 0.1 dB when amplifying 40 × 10 Gbps non-return-to-zero on-off keying signals from −20 dBm/channel.---//---This work is licensed under a CC BY 4.0 license., This work has been supported by the European Regional Development Fund project No.1.1.1.1/18/A/068. The Institute of Solid State Physics, University of Latvia as a Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2.

Standard horn antennas are widely used in antenna measurement setups for transceiver antennas application, whose absolute gain is necessary to be known in order to finally calculate the gain of antennas under test (AUT). Yet, the gain parameters of these horn antennas are often not provided completely by manufacturers and thus should be measured in our own setup. This paper aims to present an Friis-formula-based experimental method by which the gain of a standard horn antenna operating from 50 GHz to 75 GHz can be acquired. The measured gain parameters of all the standard horns covering the 50 GHz to 325 GHz has been used in our regular tests and proved to be convincible, the correctness of the calculated AUT gain in our antenna measurement setup has therefore been improved.

Generative models in molecular design tend to be richly parameterized, data-hungry neural models, as they must create complex structured objects as outputs. Estimating such models from data may be challenging due to the lack of sufficient training data. In this paper, we propose a surprisingly effective self-training approach for iteratively creating additional molecular targets. We first pre-train the generative model together with a simple property predictor. The property predictor is then used as a likelihood model for filtering candidate structures from the generative model. Additional targets are iteratively produced and used in the course of stochastic EM iterations to maximize the log-likelihood that the candidate structures are accepted. A simple rejection (re-weighting) sampler suffices to draw posterior samples since the generative model is already reasonable after pre-training. We demonstrate significant gains over strong baselines for both unconditional and conditional molecular design. In particular, our approach outperforms the previous state-of-the-art in conditional molecular design by over 10% in absolute gain. Finally, we show that our approach is useful in other domains as well, such as program synthesis., Comment: ICML 2020

Single-stage instance segmentation approaches have recently gained popularity due to their speed and simplicity, but are still lagging behind in accuracy, compared to two-stage methods. We propose a fast single-stage instance segmentation method, called SipMask, that preserves instance-specific spatial information by separating mask prediction of an instance to different sub-regions of a detected bounding-box. Our main contribution is a novel light-weight spatial preservation (SP) module that generates a separate set of spatial coefficients for each sub-region within a bounding-box, leading to improved mask predictions. It also enables accurate delineation of spatially adjacent instances. Further, we introduce a mask alignment weighting loss and a feature alignment scheme to better correlate mask prediction with object detection. On COCO test-dev, our SipMask outperforms the existing single-stage methods. Compared to the state-of-the-art single-stage TensorMask, SipMask obtains an absolute gain of 1.0% (mask AP), while providing a four-fold speedup. In terms of real-time capabilities, SipMask outperforms YOLACT with an absolute gain of 3.0% (mask AP) under similar settings, while operating at comparable speed on a Titan Xp. We also evaluate our SipMask for real-time video instance segmentation, achieving promising results on YouTube-VIS dataset. The source code is available at https://github.com/JialeCao001/SipMask.

Typically an Intelligent Transportation System (ITS) employs various types of infrastructure-based technologies into vehicles and roadways for monitoring traffic. But these solutions have high installation, maintenance, and operational costs. Further, most of these solutions are based on the assumptions of lane-based organized and homogeneous traffic, due to which these are ineffective in less organized traffic conditions which are common in developing countries. In this paper, we have proposed a cost-effective approach to infer the traffic state of the road by analyzing the cumulative acoustic signal collected from the microphone sensor of the user’s smartphone. To capture the distinctive characteristics of various traffic scenes, we explored two different types of features: Mel Frequency Cepstral Coefficients (MFCCs) and Wavelet Packet Transform (WPT). Based on the understanding of acoustic signals of different traffic scenes, various parameters of these features such as window size and MFCC dimensions are tuned for better detection accuracy and robustness. To validate the approach, field experiments were conducted in varied conditions on the roads of City X. Experimental results revealed that for binary traffic scene classification (‘busy-street’ vs. ‘quiet-street’), MFCC features are sufficient to get an overall accuracy of 100%. However, for ‘congestion’ vs. ‘medium-flow’ vs. ‘free-flow’ traffic scene classification, MFCC features yield a bit lower accuracy of 77.64%. In this scenario, it was observed that WPT features can be used to reduce the false positive rate, thereby providing an absolute gain of 11.38% in the classification accuracy over the MFCC baseline. Also, it has been observed that by crowdsourcing the traffic state information from multiple users’ smartphones, an effective accuracy improvement can be achieved for each traffic scene.

In recent years, development of various applications such as IoT and 5G has been carried out, and frequency tightness has occurred. Therefore, there is a demand for technological development beyond the quasi-millimeter wave band. we propose a microstrip antenna employing a square metal ring for quasi-millimeter wave applications. This antenna can improve and control absolute gain by using a square metal ring. It is clear that the gain can be controlled stepwise from 6.9 dBi to 9.5 dBi at 24GHz band by electromagnetic field analysis when the antenna employing square metal ring is configured to change the substrate thickness.

Redirected walking allows for natural locomotion in virtual environments that are larger than a user’s physical environment. The mapping between real and virtual motion is modified by scaling some aspect of motion. As a user traverses the virtual environment these modifications (or gains) must be dynamically adjusted to prevent collision with physical obstacles. A significant body of work has established perceptual thresholds on rates of absolute gain, but the effect of changing gain is little understood. We present the results of a user study on the effects of rate of gain change. A psychophysical experiment was conducted with 21 participants. Each participant completed a series of two-alternative forced choice tasks in which they determined whether their virtual motion differed from their physical motion while experiencing one of three different methods of gain change: sudden gain change, slow gain change and constant gain. Gain thresholds were determined by 3 interleaved 2-up 1-down staircases, one per condition. Our results indicate that slow gain change is significantly harder to detect than sudden gain change.

Detection of low-intensity light relies on the conversion of photons to photoelectrons, which are then multiplied and detected as an electrical signal. To measure the actual intensity of the light, one must know the factor by which the photoelectrons have been multiplied. To obtain this amplification factor, we have developed a procedure for estimating precisely the signal caused by a single photoelectron. The method utilizes the fact that the photoelectrons conform to a Poisson distribution. The average signal produced by a single photoelectron can then be estimated from the number of noise events, without requiring analysis of the distribution of the signal produced by a single photoelectron. The signal produced by one or more photoelectrons can be estimated experimentally without any assumptions. This technique, and an example of the analysis of a signal from a photomultiplier tube, are described in this study., Comment: 18 pages, 6 figures

Metal-halide perovskite-based tandem solar cells show great promise for overcoming the Shockley–Queisser single-junction efficiency limit via low-cost tandem structures, but so far, they employ conventional bottom-cell materials that require stringent processing conditions. Meanwhile, difficulty in achieving low-bandgap ( 11% absolute gain) to the ultimate efficiency via photon recycling. We report an initial experimental demonstration of a solution-processed monolithic perovskite/CQD tandem solar cell, showin...

This article examines a noval series-fed triangular microstrip ring resonator (TMRR) antenna array. Each radiating element is made up of a wavelength-long microstrip line with the two ends joined together to form an isosceles triangle. The antenna array is fed by an N-shaped microstrip feed line and excited by a coaxial feed probe. The operational mechanism of the proposed feed system in terms of its electrodynamics is examined with respect to its relative size occupancy, dispersion along the feed line, and the feed effect on the spatial orientation of the propagated radio waves. The size occupancy of the antenna array is 45 mm2 x 60 mm2 with a measured reflection coefficient S11 of -27.5 dB at a resonant frequency of 5.76 GHz. The simulated S11 is -29.2 dB at a resonant frequency of 5.8 GHz. The measured gain is roughly 10.46 dBi using the absolute gain method. The resulting antenna array is compact in size and exhibits reasonable performance in terms of gain, reflection coefficient, low mass/volume, and weight.

This work investigates in-depth the effects of variation of the compositional ratio of the absorber layer in Cu(In,Ga)Se2 (CIGS) thin-film solar cells. Electrical simulations were carried out in order to propose the most suitable gallium double-grading profile for the high efficiency devices. To keep the model as close as possible to the real behavior of the thin film solar cell a trap model was implemented to describe the bulk defects in the absorber layer. The performance of a solar cell with a standard CIGS layer thickness (2 μm) exhibits a strong dependence on the front grading height (decreasing band gap toward the middle of the CIGS layer). An absolute gain in the efficiency (higher than 1%) is observed by a front grading height of 0.22. Moreover, simulation results show that the position of the plateau (the region characterized by the minimum band gap) should be accurately positioned at a compositional ratio of 20% Ga and 80% In, which corresponds to the region where a lower bulk defect density is expected. The developed model demonstrates that the length of the plateau is not playing a relevant role, causing just a slight change in the solar cell performances. Devices with different absorber layer thicknesses were simulated. The highest efficiency is obtained for a CIGS thin film with thicknesses between 0.8 and 1.1 μm.

Translation quality estimation is a task of growing importance in NLP, due to its potential to reduce post-editing human effort in disruptive ways. However, this potential is currently limited by the relatively low accuracy of existing systems. In this paper, we achieve remarkable improvements by exploiting synergies between the related tasks of word-level quality estimation and automatic post-editing. First, we stack a new, carefully engineered, neural model into a rich feature-based word-level quality estimation system. Then, we use the output of an automatic post-editing system as an extra feature, obtaining striking results on WMT16: a word-level FMULT1 score of 57.47% (an absolute gain of +7.95% over the current state of the art), and a Pearson correlation score of 65.56% for sentence-level HTER prediction (an absolute gain of +13.36%).

Numerous video head impulse test (vHIT) devices are available commercially; however, gain is not calculated uniformly. An evaluation of these devices/algorithms in healthy controls and patients with vestibular loss is necessary for comparing and synthesizing work that utilizes different devices and gain calculations.Using three commercially available vHIT devices/algorithms, the purpose of the present study was to compare: (1) horizontal canal vHIT gain among devices/algorithms in normal control subjects; (2) the effects of age on vHIT gain for each device/algorithm in normal control subjects; and (3) the clinical performance of horizontal canal vHIT gain between devices/algorithms for differentiating normal versus abnormal vestibular function.Prospective.Sixty-one normal control adult subjects (range 20–78) and eleven adults with unilateral or bilateral vestibular loss (range 32–79).vHIT was administered using three different devices/algorithms, randomized in order, for each subject on the same day: (1) Impulse (Otometrics, Schaumberg, IL; monocular eye recording, right eye only; using area under the curve gain), (2) EyeSeeCam (Interacoustics, Denmark; monocular eye recording, left eye only; using instantaneous gain), and (3) VisualEyes (MicroMedical, Chatham, IL, binocular eye recording; using position gain).There was a significant mean difference in vHIT gain among devices/algorithms for both the normal control and vestibular loss groups. vHIT gain was significantly larger in the ipsilateral direction of the eye used to measure gain; however, in spite of the significant mean differences in vHIT gain among devices/algorithms and the significant directional bias, classification of “normal” versus “abnormal” gain is consistent across all compared devices/algorithms, with the exception of instantaneous gain at 40 msec. There was not an effect of age on vHIT gain up to 78 years regardless of the device/algorithm.These findings support that vHIT gain is significantly different between devices/algorithms, suggesting that care should be taken when making direct comparisons of absolute gain values between devices/algorithms.

A modified microstrip Franklin array antenna (MFAA) is proposed for short-range radar applications in vehicle blind spot information systems (BLIS). It is shown that the radiating performance [i.e., absolute gain value and half-power beamwidth (HPBW) angle] can be improved by increasing the number of radiators in the MFAA structure and assigning appropriate values to the antenna geometry parameters. The MFAA possesses a high absolute gain value (>10 dB), good directivity (HPBW 80°) in the H-plane at an operating frequency of 24 GHz. Moreover, the 10-dB impedance bandwidth of the proposed antenna is around 250 MHz. The MFAA is, thus, an ideal candidate for automotive BLIS applications.

A built-in-self-test (BIST) system for wideband phase arrays channels is presented. The BIST is implemented using an on-chip in-phase/quadrature ( $I/Q$ ) receiver with an integrated ring oscillator that provides both the channel test signal and the mixer local oscillator (LO). The BIST achieves wideband accuracy for relative phase and gain measurements at 2–15 GHz with a one-time self-correction algorithm with eight LO phases. The sequential algorithm determines the $I/Q$ errors, such as dc offset, gain and phase imbalances from the $I/Q$ outputs resulting from different LO phase states. An rms power detector network is also implemented for absolute gain measurements. The BIST can operate at rates >1 MHz (less than 1- $\mu \text{s}$ sampling time) with signal-to-noise ratio greater than 50 dB and provides measurements that agree well with the vector network analyzer S-parameter data over a wide frequency range. To the best of our knowledge, this is the first implementation of high accuracy wideband BIST system for phased-array channels.

An integrated top layer with single feed compact size MSA designed for the desired communication like Wireless local area network (WLAN) which combines the network along with wireless technology. Resonant frequency has been achieved by use of simple rectangular patch and circular patch deducted from the top layer. The simulated antenna characteristics designed by using method of moment based EM solution software named IE3D. In this paper we are analyze S11 parameter in dB, beam-width and absolute gain (dBi) for the designed antenna structure.

In this paper, design, simulation, production and measurement of a coplanar broadband microstrip antenna printed on an alumina ceramic substrate is presented. Antenna may be used as an element in a radar applications operating at X-band (8 GHz-12 GHz). The antenna driven system consists of one more directors because of the requirements of directivity. The reason of using high dielectric substrates the antenna can be printed on very small spaces. Antenna in Package structure's temperatures rising up rapidly in radar applications so the use of ceramic substrates also has the advantage of using the antenna in high temperature conditions. The whole structure achieves a measured 52% frequency bandwidth for voltage standing-wave ratio ≤ 2 and 8–10 dBi absolute gain. The minimum line widths on the antenna is about 25 µm so thin film technology is used in the fabrication process importance of the antenna.

In this paper, a miniaturized inverted λ-dipole antenna printed on a miniaturized area of an FR-4 substrate for modern wireless applications including internet of things is investigated in this paper. The antenna dipole is constructed from an inverted λ structure with a reflector connected to the antenna and an inverted short L-ground plane to meet the requirements of the portable miniaturized devices. The used FR-4 substrate thickness is 1.5mm of a rigid structure with er=3.4 and loss tangent of 0.00198. The antenna is lunched to a complementary Split Ring Resonators (SRR) array of 9×9 unit cells to realize an absolute gain enhancement, about 7dBi, over the frequency band, |S11

This paper presents high directive low cross-polarized 4 × 4 antenna array for Ku-band application. It consists of four 2 × 2 subarrays. The single element of the array is designed from the modified Baravelle’s spiral geometry, which resonates at 13.01 GHz. In 2 × 2 subarray, by introducing delay-feed line, the lower elements have a delay compared to upper elements. By using this scheme, a 4 × 4 array has been designed and achieved good side-lobe as well as grating lobe suppression. The feed network of the array is designed in such a manner, to make the structure compact in size and to get a highly directive beam pattern from it. Finally, experiments are carried out to verify the designed prototypes. Measured results show that the single element has a high gain of 9.82 dBi and impedance bandwidth of 6.42 % with a radiation efficiency of 88.70 % . The array gives an absolute gain of 18.40 dBi and impedance bandwidth of 6.78 % . The measured radiation efficiency of the array is 74.54 % . Both the antenna and array gives less than - 40 dB cross-polarization along the boresight ( θ = 0 ° ) direction. Experimental results show that the proposed antennas are suitable for Ku-band applications.

This paper presents millimeter-wave and terahertz double bow-tie slot antennas on a synthesized elliptical silicon lens. Two different antennas are designed to cover 0.1–0.3 and 0.2–0.6 THz, respectively. The double bow-tie slot antenna results in a wide impedance bandwidth and 78–97% Gaussian coupling efficiency over a 3:1 frequency range. A wideband coplanar-waveguide low-pass filter is designed using slow-wave techniques, and the measured filter response shows an S $_{21}$ < −25 dB over a 3:1 frequency range. Absolute gain measurements done at 100–300 GHz and 200–600 GHz confirm the wideband operation of this design. The double bow-tie slot antenna is intended to fill the gap between standard double-slot antennas and log periodic and sinuous antennas, with applications areas in radio astronomy and imaging systems.

A compact CPW-fed metamaterial (MTM)-inspired zeroth-order resonating (ZOR) antenna is presented with backed ground plane. Such MTM antenna consists of thin conducting line and a bow-tie shaped patch connected to CPW feed. The proposed structure shows compact size with radiating element dimensions of $0.095{{\lambda }_{\text{o}}} \times 0.042{{\lambda }_{\text{o}}} \times 0.013{{\lambda }_{o}}$ by introducing ground plane at bottom. As an advantage, resonant frequency is shifted toward left which corresponds to 57.9% miniaturization area with respect to the proposed antenna without backed plane (resonating at 3.7 GHz). The proposed MTM antenna exhibits zeroth-order resonance (ZOR) at 2.4 GHz and has an impedance bandwidth ( ${S11} .) of 25.4%. The proposed structure shows good radiation characteristics with simulated absolute gain of 1.59 dBi and simulated radiation efficiency of 91.5% throughout the operating bandwidth. Now for extending the bandwidth and shifting the resonant frequency to be operated in WiMAX band (3.5–3.57 GHz), electromagnetic band gap (EBG) structures are loaded in upper ground plane. This antenna shows an impedance bandwidth of 54.2% and resonates at 3.3 GHz. The radiation patterns are consistent throughout the working band. The prototype structures have been fabricated and experimentally validated. The designed antennas are suitable for use in LTE, WLAN, and WiMAX (2.5/3.5 GHz).

Application of progeny test breeding values to forecast yield gains at rotation-age in genetically improved stands remains a very challenging yet crucial task for breeders of Douglas-fir and other long-rotation timber species such as western hemlock, white spruce, Norway spruce, and Scots pine. Evaluation of the economic returns on genetic improvement requires reliable estimates of yield gains at rotation age. Large-plot realized gain trials should provide more accurate estimates of yield gain than inferences from progeny tests, but are most dependable when they reach rotation age or at least approach rotation age. A set of coastal Douglas-fir realized genetic gain trials in western Oregon, based on a first-generation breeding program, was measured most recently at plantation ages ranging between 17 and 21 years. The trial was established on five sites at a spacing wide enough (3.6 × 3.6 m) to assume that the trees could be grown to rotation age with no further silvicultural intervention. A growth model, CIPSANON v. 4.0, projected the current tree lists from these trials to plantation age 60 years to facilitate estimation of yield gains at various rotation ages up to 60 years. The following two simulation approaches were explored: (1) apply genetic-gain multipliers developed from a previous study for diameter and height growth, and (2) assume that genetic gain differences were fully represented by plot-level site index expressed at the most recent measurement. The two approaches resulted in similar estimates of realized yield gain at plantation ages up to 60 years. Relative gain decreased over time, but absolute gain (in cubic meters or board feet) increased over time. Relative stand volume gain simulated to the average current rotation age of 50 years was about 30% of the relative realized gain measured at plantation age 10/12 years (birth age 13/15 years) and about 38% of the relative realized gain measured at plantation age 17–21 years (birth age 20–24 years). Several validation needs were identified including magnitude of genetic-gain multipliers, duration of annual multiplier application over the duration of a simulation, adjustment of multipliers as the stand ages, and most appropriate multiplier resolution (tree versus stand). A potentially critical knowledge gap remains about any genetic improvement effects on yield gains associated specifically with increased carrying capacity that would be consistent with the crop ideotype concept.

The gain characteristics of a semiconductor optical amplifier (SOA) that contains forty layers of closely stacked InAs/GaAs quantum dots (QDs) were studied by employing a fiber-to-fiber measurement system. The fiber-to-fiber gain values obtained for transverse-electric (TE)- and transverse-magnetic (TM)-polarized optical input signals exhibited their maxima at a wavelength of 1100 nm, which corresponds to the excited state of the closely stacked QDs. In the wavelength range from 1060 to 1170 nm, the gain obtained for TE-polarized input signal was slightly higher than that for TM-polarized input signal and the absolute gain difference was less than 1 dB for an injection current of 80 mA. The small but non-zero difference of the gain reflects the polarization anisotropy of the optical gain provided by the closely stacked QDs. Our results suggest that closely stacked QDs are suitable for realizing polarization-insensitive SOA device with operation bandwidths of more than 100 nm.

Single-object tracking is a significant and challenging computer vision problem. Recently, discriminative correlation filters (DCF) have shown excellent performance. But there is a theoretical defects that the boundary effect, caused by the periodic assumption of training samples, greatly limit the tracking performance. Spatially regularized DCF (SRDCF) introduces a spatial regularization to penalize the filter coefficients depending on their spatial location, which improves the tracking performance a lot. However, this simple regularization strategy implements unequal penalties for the target area filter coefficients, which makes the filter learn a distorted object appearance model. In this paper, a novel spatial regularization strategy is proposed, utilizing a reliability map to approximate the target area and to keep the penalty coefficients of relevant region consistent. Besides, we introduce a spatial variation regularization component that the second-order difference of the filter, which smooths changes of filter coefficients to prevent the filter over-fitting current frame. Furthermore, an efficient optimization algorithm called alternating direction method of multipliers (ADMM) is developed. Comprehensive experiments are performed on three benchmark datasets: OTB-2013, OTB-2015 and TempleColor-128, and our algorithm achieves a more favorable performance than several state-of-the-art methods. Compared with SRDCF, our approach obtains an absolute gain of 6.6% and 5.1% in mean distance precision on OTB-2013 and OTB-2015, respectively. Our approach runs in real-time on a CPU.

The paper presents simulation results of the C-band digitally controlled active vector-sum phase shifter (VSPS) which is implemented in 0.18 μm SiGe BiCMOS technology. VSPS provides digital 6-bit discrete phase control in the range from 0° to 354.5° with 5.625° step. Power consumption is below 110 mW. Post-layout simulation of VSPS shows absolute phase error

Tandem solar cells (TSCs) based on solution-processable semiconductors, including metal-halide perovskites and organic materials, show great promise for overcoming the Shockley-Queisser efficiency limit at low cost. However, difficulty in obtaining low-bandgap ( 11% absolute gain) to the ultimate efficiency via photon recycling. We emphasize the significance of using materials with high luminescence quantum efficiencies to benefit from this important effect. Initial laboratory demonstration of monolithic TSCs operating in the radiative-coupling regime is currently underway.

International audience; In this paper, a low-cost patch antenna with circular polarization using a FR4 substrate is proposed. The antenna was developed to be used in US standard UHF RFID application, with better impedance matching at 915MHz. The design was concepted and optimized through simulations using the ANSYS HFSS software. The simulation results presented an absolute gain of 5.76dB, an axial ratio of 1.87dB and the return loss (S11) of 48dB at 915MHz. The antenna was manufactured and measurements of the return loss using the Keysight Vector Network Analyzer were made to compare with the simulation results. Furthermore, it was compared to a commercial antenna by reading a commercial tag using a RFID reader in order to validate the proposed antenna application.

An electrically small antenna for future 5G millimeter-wave applications is presented. The proposed antenna has a size of 4×4 mm2, The antenna is semi-circular in shape with an arc slot, resulting in a broadband characteristic. The proposed antenna has a wide impedance bandwidth that ranges from 23 to 37 GHz. The antenna has a maximum absolute gain of 3.44 dBi and is more than 89% efficient. The length of any side is less than 0.49λ 0 at 23 GHz, making it extremely useful for array configuration deployment. Modelled on thin Rogers substrate with attractive characteristics and low-cost fabrication requirements, this antenna becomes an excellent candidate for future 5G communications.

A low-profile tightly coupled phased array antenna with the characteristics of 3:1 bandwidth and $\mathbf{\pm 45^{\circ}scan}$ has been proposed in this paper. The array element consists of three layers of Duroid 5880 substrates and a couple of dipole arms. The novelty of the design is the loaded cross-shaped patch which is employed to avoid the common-mode resonance when unbalanced feeding the balanced dipoles. The obtained results confirm that, the array with 7mm spacing can operate from 7 to 21 GHz with VSWR $\leq 2.5$ for 45°scan in both E-and H-planes. The absolute gain of embedded central element pattern is less than 0.6dB compared with the ideal gain, indicating low loss and good efficiency. It is also worth mentioning that, the whole thickness of the antenna is around 4.5mm, which means it is suitable for conformal platforms.

This paper presents the simulation results of the C-band digitally controlled variable gain amplifier (VGA) which is implemented in 0.18 μm SiGe BiCMOS technology. VGA provides digital 5-bit discrete gain control in the range from 0 to −31 dB with 1 dB step. Noise figure is less than 18 dB. Power consumption is 17.25 mW. The simulation of the VGA shows absolute gain error

In this paper, based on rigid-flex printed circuit board (PCB), a compact solution of Antenna-in-Package (AiP) including RF transmitter and microstrip passive phased antenna array is demonstrated. Apart from the landing of two connectors, the size shrinks down to 35 mm × 32 mm. RF transmitter works at the band of 26.2 GHz to 27.2 GHz, with conversion gain of 13 dB and rejection ratio up to 17.5 dBc. The 1 × 4 microstrip passive phased antenna array integrating 4 × 4 Butler Matrix achieves four scanning angles which are -10°, 30°, -30° and 10° with 20° half power beam width (HPBW), and simulated absolute gain is 13.51 dBi, 12.31 dBi, 12.23 dBi and 13.26 dBi respectively. Minor deviation on scanning angles from simulation data is observed in the testing due to measurement and manufacturing tolerance. However, among operating bandwidth, HPBW, main-to-side lobe ratio and the difference between two scanning angles when port 1, 4 and port 2, 3 are excited respectively are in good agreement with simulation results

Compositional grading has been widely exploited in highly efficient Cu(In,Ga)Se2, CdTe, GaAs, quantum dot solar cells, and this strategy has the potential to improve the performance of emerging perovskite solar cells. However, realizing and maintaining compositionally graded perovskite absorber from solution processing is challenging. Moreover, the operational stability of graded perovskite solar cells under long‐term heat/light soaking has not been demonstrated. In this study, a facile partial ion‐exchange approach is reported to achieve compositionally graded perovskite absorber layers. Incorporating compositional grading improves charge collection and suppresses interface recombination, enabling to fabricate near‐infrared‐transparent perovskite solar cells with power conversion efficiency of 16.8% in substrate configuration, and demonstrate 22.7% tandem efficiency with 3.3% absolute gain when mechanically stacked on a Cu(In,Ga)Se2 bottom cell. Non‐encapsulated graded perovskite device retains over 93% of its initial efficiency after 1000 h operation at maximum power point at 60 °C under equivalent 1 sun illumination. The results open an avenue in exploring partial ion‐exchange to design graded perovskite solar cells with improved efficiency and stability.