Gain Deviation Research Articles

Birthweight, lifetime obesity and physical functioning in mid-adulthood: a nationwide birth cohort study.

Evidence is scant on long-term implications of childhood obesity and body mass index (BMI) gains over the life-course for poor physical functioning (PF). The objective was to establish whether (i) birthweight and BMI across the life-course, (ii) BMI gains at specific life-stages and (iii) age of obesity onset were associated with PF at 50 y. In the 1958 British birth cohort (n = 8674), BMI (kg/m2) was calculated using height and weight [measured (7, 11, 16, 33 and 45 y); self-reported (23 and 50 y)]. PF was assessed at 50 y using the validated PF subscale of the Short-form 36 survey; the bottom (gender-specific) 10% was classified as poor PF. Missing data were imputed via multiple imputation. Associations were examined using logistic regression, adjusting for health and social factors. Birthweight was not associated with PF. At each adult age, odds of poor PF were highest for obese (vs normal), e.g. for 23 y obesity the odds ratio (OR)adjusted for poor PF was 2.28 (1.34, 3.91) and 2.67 (1.72, 4.14) in males and females respectively. BMI gains were associated with poor PF, e.g. for females, ORadjusted per standard deviation (SD) in BMI gain 16-23 y was 1.28 (1.13, 1.46); for BMI gains 45-50 y it was 1.36 (1.11, 1.65). Longer duration of obesity was associated with poor PF, e.g. in males, ORadjusted was 2.32 (1.26, 4.29) for childhood obesity onset and 1.50 (1.16, 1.96) for mid-adulthood onset (vs never obese, P-trend < 0.001). Obesity, BMI gains, and earlier obesity onset were associated with poor PF in mid-adulthood, reinforcing the importance of preventing and delaying obesity onset.

Robust fault detection and estimation observer design for switched systems

The main purpose of this paper is to study the problem of fault detection and estimation for switched systems based on DC–DC converters. Firstly, we transform DC–DC converters into switched systems. Secondly, to achieve the purpose of the fault detection and estimation, we design a sliding mode observer(SMO) to produce residual signal. By comparing the set threshold and the residual produced by SMO, we can detect whether a fault has occurred. Meanwhile, fault estimation is realized through the method of fault reconstruction. Finally, in order to show the feasibility of this sensor fault detection and estimation, the simulation of three sensor faults which include open-circuit, gain deviation and noise abnormity is given in this paper.

Inductor-less PVT robust gain switching balun LNA for multistandard applications

ABSTRACTAn inductor-less single to differential low-noise amplifier (LNA) is proposed for multistandard applications in the frequency band of 0.2–2 GHz. The proposed LNA incorporates noise cancellation and voltage shunt feedback configuration to achieve minimum noise characteristics and low power consumption. In addition to noise cancellation, trans-conductance of common-source stage is scaled to improve the noise performance. In this way, noise figure (NF) of LNA below 3 dB is achieved. An additional capacitor Cc is used to correct the gain and phase imbalance at the output. The gain switching has been enabled with a step size of 4 dB for high linearity and power efficiency. The bias point of all transistors is chosen such that the variation in gm is not more than 10%. The proposed LNA is implemented in UMC 0.18-μm RF CMOS technology. The core area is 182 μm × 181 μm. Moreover, the LNA has better ratio of relevant performance to area. The proposed balun LNA is validated by rigorous Monte Carlo simulation. The 3σ deviation of gain and NF is less than 5%. Finally, the proposed LNA is robust to unavoidable PVT variations.

Sensor fault detection and estimation for switched power electronics systems based on sliding mode observer

In this paper, the problem of sensor fault detection and estimation (FDE) for power electronics systems such as DC-DC buck-boost converter is investigated. Firstly, the power electronics system is modeled, and the fault model is given. Then based on the switched Lyapunov function technique, a sliding mode observer (SMO) is designed for the switched error systems, which can guarantee that the error systems are asymptotically stable with a prescribed H∞ performance index. Next, comparing the set threshold with the residual which is produced by the sliding mode observer, the sensor fault detection can be achieved. Meanwhile, based on the method of fault reconfiguration, fault estimation is realized. Finally, in order to show the feasibility of this sensor fault detection and estimation, the simulation of three kinds of sensor faults including open-circuit, gain deviation and noise abnormity is given in this article.

A Compact Quasi-Isotropic Dielectric Resonator Antenna With Filtering Response

A compact quasi-isotropic dielectric resonator (DR) antenna (DRA) with filtering response is first investigated in this communication. The cylindrical DRA is fed by a microstrip-coupled slot, exciting in its HEM11δ mode which radiates like a magnetic dipole. A small ground plane is used for this DRA and it radiates like an electric dipole. The combination of the two orthogonal dipoles leads to a quasi-isotropic radiation pattern, with gain deviation as low as 5.8 dB in the 360° full space. To integrate the filtering function, the microstrip feed-line and the ground plane are turned upside down, and further two stubs with different lengths are used together to excite the DR. Due to the different loading effects of the feeding stubs, two resonances of the DR HEM11δ mode are excited in the passband, effectively enhancing the bandwidth of DRA (ε <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</sub> = 20) to 7%. Furthermore, two controllable radiation nulls are generated by the DR loaded microstrip feed-line, bringing about high frequency selectivity at the edges of the passband and a quasi-elliptic bandpass response. For demonstration, a prototype operating at 2.4 GHz was fabricated and tested; reasonable agreement is obtained between the simulated and measured results.

Sensor Fault Detection and Fault-Tolerant Control for Buck Converter via Affine Switched Systems

The main purpose of this paper is to study the problem of the sensor fault detection and fault-tolerant control for DC–DC buck converter via affine switched systems. First, the buck converter is model as a switched system model, and a robust fault detection observer with a prescribed <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$H_{\infty }$ </tex-math></inline-formula> performance index is designed to produce a residual signal. The residual signal can be used to construct the residual estimation function. Second, fault detection logic is introduced which compares the threshold with the residual estimation function, and the sensor fault detection can be achieved. Third, once the sensor fault is detected, fault-tolerant control can be achieved through the method of system reconfiguration. This method enables the system to achieve asymptotic stability in a new system under the sensor fault. Finally, to show the feasibility of the fault detection and fault-tolerant control, the simulation results of three kinds of sensor faults including open-circuit, gain deviation, and noise abnormity given in this paper.

A PVT-Robust Analog Baseband With DC Offset Cancellation for FMCW Automotive Radar

This paper presents a process-voltage-temperature (PVT)-robust analog baseband with DC offset cancellation (DCOC) for automotive radar applications. The baseband is composed of three stages of programmable gain amplifier (PGA) and an embedded fifth-order Butterworth filter. A novel embedded Gm-cell based DCOC feedback loop is proposed to achieve fine DC offset rejection and a low high-pass the cut-off frequency with an economic chip area. The proposed embedded Gm-cell based DCOC feedback topology is capable of improving gain error and loop stability simultaneously. Besides, a constant overdrive biasing technique is proposed to strengthen PVT robustness. Implemented in 65-nm CMOS technology, the measured results show that the analog baseband can provide a programmable gain range from 18.2 to 70.6 dB with 5.8 dB per step with a gain error of <;0.2 dB, while the 1-dB bandwidth range is from 200 kHz to 10 MHz. An OIP3 of 7.8 dBm and an input referred noise (IRN) of 15.8 nV/√Hz are obtained. The gain deviation is lower than 2.2 dB across all PVT corners. The core circuit consumes a dc power of 6 mW from a 1.2-V supply and occupies a chip area of 0.1 mm 2 .

Effects of Abdominal Massage on the Weight Gain of Preterm Infants Hospitalized in Selected Hospitals of Isfahan, Iran: A Randomized Controlled Clinical Trial

Background: Birth weight is one of the decisive factors in infant vulnerability and mortality. The impact of a full-body massage on the weight gain of preterm infants has been taken into account. Nevertheless, very few studies have been conducted on effects of abdominal massage. Hence, the current study was carried out to explore effects of abdominal massage on the weight gain of preterm infants hospitalized in neonatal intensive care units. Materials and Methods: This study was a single-blind randomized controlled clinical trial, conducted on 64 preterm infants hospitalized in neonatal intensive care units in selected hospitals of Isfahan. They were randomly categorized into two groups, namely control and intervention. The pre-feeding weight of the infants in the groups was recorded daily. They were fed using an orogastric tube every two hours. One hour after the feeding, a researcher (with a master’s degree in Neonatal Intensive Care Nursing) gave abdominal massage to the infants in the intervention group twice a day, at 2.00 p.m. and 8.00 a.m., for 15 minutes, during a five-day period. However, the control group received the routine care in the unit. Data were analyzed using the SPSS software version 23.0, and analytical as well as descriptive statistical methods. Results: Regarding their gender, 38 infants (59.3%) were male; the mean and standard deviation (SD) of weight gain during five days were more in the intervention group (1480.76±31.29) than in the control group (1365.83±41.93). This difference was statistically significant (p < 0.05). Conclusion According to the results of the present study, abdominal massage seems to improve weight gain in preterm infants and could be substituted for a full-body massage.

Development of a Portable Muography Detector for Infrastructure Degradation Investigation

A portable muography detector was developed for measuring infrastructure degradation and its performance was tested. The detector consists of two muon position sensitive detectors (mu-PSDs) of the area of 140 mm $\times \,\, 140$ mm, placed in a compact light-shielding box. Each mu-PSD consists of plastic scintillating fibers connected to multipixel photon counters (MPPCs). To suppress the gain deviation of the MPPCs, the box was heat insulated and its inner air temperature was maintained by Peltier cooling–heating modules. The mu-PSD pixel size was 8.75 mm $\times \,\, 8.75$ mm and the distance between the two mu-PSDs was set to 100 mm in order to achieve a solid angle resolution of 8 msr when measuring typical pieces of infrastructure at thicknesses of several tens of centimeters. The intensity of cosmic-ray muons was measured as a function of zenith angle on the ground and was found to be in good agreement with the well-known empirical formula for muon intensity at Earth’s surface. The structural interior of a seven-story concrete building was then successfully imaged with the muography detector placed in the building’s basement.

Multi-parameter Nonlinear Gain Correction of X-ray Transition Edge Sensors for the X-ray Integral Field Unit

With its array of 3840 Transition Edge Sensors (TESs), the Athena X-ray Integral Field Unit (X-IFU) will provide spatially resolved high-resolution spectroscopy (2.5 eV up to 7 keV) from 0.2 to 12 keV, with an absolute energy scale accuracy of 0.4 eV. Slight changes in the TES operating environment can cause significant variations in its energy response function, which may result in systematic errors in the absolute energy scale. We plan to monitor such changes at pixel level via onboard X-ray calibration sources and correct the energy scale accordingly using a linear or quadratic interpolation of gain curves obtained during ground calibration. However, this may not be sufficient to meet the 0.4 eV accuracy required for the X-IFU. In this contribution, we introduce a new two-parameter gain correction technique, based on both the pulse-height estimate of a fiducial line and the baseline value of the pixels. Using gain functions that simulate ground calibration data, we show that this technique can accurately correct deviations in detector gain due to changes in TES operating conditions such as heat sink temperature, bias voltage, thermal radiation loading and linear amplifier gain. We also address potential optimisations of the onboard calibration source and compare the performance of this new technique with those previously used.

Pregnancy Weight Gain by Gestational Age in Women with Uncomplicated Dichorionic Twin Pregnancies.

Twin pregnancies are at increased risk for adverse outcomes and are associated with greater gestational weight gain compared to singleton pregnancies. Studies that disentangle the relationship between gestational duration, weight gain and adverse outcomes are needed to inform weight gain guidelines. We created charts of the mean, standard deviation and select percentiles of maternal weight gain-for-gestational age in twin pregnancies and compared them to singleton curves. We abstracted serial prenatal weight measurements of women delivering uncomplicated twin pregnancies at Magee-Womens Hospital (Pittsburgh, PA, 1998-2013) and merged them with the hospital's perinatal database. Hierarchical linear regression was used to express pregnancy weight gain as a smoothed function of gestational age according to pre-pregnancy BMI category. Charts of week- and day-specific values for the mean, standard deviation, and percentiles of maternal weight gain were created. Prenatal weight measurements (median: 11 [interquartile range: 9, 13] per woman) were available for 1109 women (573 normal weight, 287 overweight, and 249 obese). The slope of weight gain was most pronounced in normal weight women and flattened with increasing pre-pregnancy BMI (e.g. 50th percentiles of 6.8, 5.7, and 3.6 kg at 20 weeks and 19.8, 18.1, and 14.4 at 37 weeks in normal weight, overweight, and obese women, respectively). Weight gain patterns in twins diverged from singletons after 17-19 weeks. Our charts provide a tool for the classification of maternal weight gain in twin pregnancies. Future work is needed to identify the range of weight gain associated with optimal pregnancy health outcomes.

Design and Analysis of a Series-Fed Aperture-Coupled Antenna Array With Wideband and High-Efficient Characteristics

In this paper, a new wideband series-fed antenna array is proposed and analyzed. The antenna array structure consists of two antennas with two ports, two antennas with one port, and a wideband 180° coupler. A portion of power is propagated by the antenna with two ports, and the rest is propagated by the antenna with one port. A new wideband 180° coupler is designed in order to make the feed structure as compact as possible and to be integrated with the antenna array. Due to using elements with wideband structure, the overall antenna is wideband with measured bandwidth of 40% with reflection coefficient of 10 dB and 3 dB gain deviation from 3.85 to 5.75 GHz. The measured peak gain of 13.4 dBi has been achieved for the proposed 1 x 4 antenna array. The measured results shows that the efficiency is better than 87% and side lobe level at the frequencies of 4.6 and 5.4 GHz are, respectively, nearly -14 and -12 dB.

Characterization of gain and directivity of exponential horn receivers.

It is difficult and expensive to match the sensitivity of the most sensitive vertebrate ears with off-the-shelf microphones due to the self-noise of the sensor. The extremely small apertures of microelectromechanical microphones create options to use horn waveguides to amplify sound prior to transduction without resulting in an unacceptably narrow directivity. Substantial gain can be achieved at wavelengths larger than the horn. An analytical model of an exponential horn embedded in a rigid spherical housing was formulated to describe the gain relative to a free-field receiver as a function of frequency and angle of arrival. For waves incident on-axis, the analytical model provided an accurate estimate of gain at high frequencies as validated by experimental measurement. Numerical models, using the equivalent source method, can account for higher order modes and comprehensively describe the acoustic scattering within and around the horn for waves arriving from any direction. Results show the directivity of horn receivers were adequately described by the analytical model up to a critical wavelength, and the mechanisms of deviation in gain at high frequencies and large angles of arrival were identified.

Bias-Voltage Stabilizer for HVHF Amplifiers in VHF Pulse-Echo Measurement Systems.

The impact of high-voltage–high-frequency (HVHF) amplifiers on echo-signal quality is greater with very-high-frequency (VHF, ≥100 MHz) ultrasound transducers than with low-frequency (LF, ≤15 MHz) ultrasound transducers. Hence, the bias voltage of an HVHF amplifier must be stabilized to ensure stable echo-signal amplitudes. We propose a bias-voltage stabilizer circuit to maintain stable DC voltages over a wide input range, thus reducing the harmonic-distortion components of the echo signals in VHF pulse-echo measurement systems. To confirm the feasibility of the bias-voltage stabilizer, we measured and compared the deviations in the gain of the HVHF amplifier with and without a bias-voltage stabilizer. Between −13 and 26 dBm, the measured gain deviations of a HVHF amplifier with a bias-voltage stabilizer are less than that of an amplifier without a bias-voltage stabilizer. In order to confirm the feasibility of the bias-voltage stabilizer, we compared the pulse-echo responses of the amplifiers, which are typically used for the evaluation of transducers or electronic components used in pulse-echo measurement systems. From the responses, we observed that the amplitudes of the echo signals of a VHF transducer triggered by the HVHF amplifier with a bias-voltage stabilizer were higher than those of the transducer triggered by the HVHF amplifier alone. The second, third, and fourth harmonic-distortion components of the HVHF amplifier with the bias-voltage stabilizer were also lower than those of the HVHF amplifier alone. Hence, the proposed scheme is a promising method for stabilizing the bias voltage of an HVHF amplifier, and improving the echo-signal quality of VHF transducers.

Analisis Penerapan Process Standard Offset pada Mesin Cetak Lembaran di PT. Percetakan Gramedia Cikarang

The development of printing industry are faster on the digital printing and the Internet are moving online world. This would erode offset printing and industrial markets, is a challenge for the field of printing offset printing media. Steps to answer the challenge was the implementation of Process Standard Offset is expected to maintain the quality is guaranteed and applies to the entire world. ISO 112647‐2 is standard for Offset where PT. Percetakan Gramedia Cikarang already certified for the process. But still encountered obstacles during implementation so that raises the question, whether the application of the Offset Standard PROCESS there are irregularities? So of writing this study can find problems in the application of Process Standard Offset. In this quantitative research data collection taken from the prints in order “A” in the machine KBA Rapida 105 on Coated paper with this parameter measurements on paper color, ink color, dot gain and measured at the color bar and dot step. So that the figures obtained ΔE * and dot gain deviations when compared with ISO 12647‐2. From the analysis of the measured data was found deviations in color and dot gain control, so we need to make improvement to keep the appropriate level of quality expected by the customer.

Scale Control and Quality Management of Printed Image Parameters

The article provides a comparison of the main valuation techniques for a regulated parameter of printability of the offset paper by current standards GOST 24356 and ISO 3783: 2006. The results of development and implementation of a complex test scale for management and control the quality of printed production are represented. The estimation scale is introduced. It includes normalized parameters of print optical density, print uniformity, picking out speed, the value of dot gain, print contrast with the added criteria of minimizing microtexts, a paper slip, resolution threshold and effusing ability of paper surface. The results of analysis allow directionally form surface properties of the substrate to facilitate achieving the required quality of the printed image parameters, i. e. optical density of a print at a predetermined level not less than 1.3, the print uniformity with minimal deviation of dot gain about the order of 10 per cents.

Power MOSFET Linearizer of a High-Voltage Power Amplifier for High-Frequency Pulse-Echo Instrumentation.

A power MOSFET linearizer is proposed for a high-voltage power amplifier (HVPA) used in high-frequency pulse-echo instrumentation. The power MOSFET linearizer is composed of a DC bias-controlled series power MOSFET shunt with parallel inductors and capacitors. The proposed scheme is designed to improve the gain deviation characteristics of the HVPA at higher input powers. By controlling the MOSFET bias voltage in the linearizer, the gain reduction into the HVPA was compensated, thereby reducing the echo harmonic distortion components generated by the ultrasonic transducers. In order to verify the performance improvement of the HVPA implementing the power MOSFET linearizer, we measured and found that the gain deviation of the power MOSFET linearizer integrated with HVPA under 10 V DC bias voltage was reduced (−1.8 and −0.96 dB, respectively) compared to that of the HVPA without the power MOSFET linearizer (−2.95 and −3.0 dB, respectively) when 70 and 80 MHz, three-cycle, and 26 dBm input pulse waveforms are applied, respectively. The input 1-dB compression point (an index of linearity) of the HVPA with power MOSFET linearizer (24.17 and 26.19 dBm at 70 and 80 MHz, respectively) at 10 V DC bias voltage was increased compared to that of HVPA without the power MOSFET linearizer (22.03 and 22.13 dBm at 70 and 80 MHz, respectively). To further verify the reduction of the echo harmonic distortion components generated by the ultrasonic transducers, the pulse-echo responses in the pulse-echo instrumentation were compared when using HVPA with and without the power MOSFET linearizer. When three-cycle 26 dBm input power was applied, the second, third, fourth, and fifth harmonic distortion components of a 75 MHz transducer driven by the HVPA with power MOSFET linearizer (−48.34, −44.21, −48.34, and −46.56 dB, respectively) were lower than that of the HVPA without the power MOSFET linearizer (−45.61, −41.57, −45.01, and −45.51 dB, respectively). When five-cycle 20 dBm input power was applied, the second, third, fourth, and fifth harmonic distortions of the HVPA with the power MOSFET linearizer (−41.54, −41.80, −48.86, and −46.27 dB, respectively) were also lower than that of the HVPA without the power MOSFET linearizer (−25.85, −43.56, −49.04, and −49.24 dB, respectively). Therefore, we conclude that the power MOSFET linearizer could reduce gain deviation of the HVPA, thus reducing the echo signal harmonic distortions generated by the high-frequency ultrasonic transducers in pulse-echo instrumentation.

Design of a compact dualband quasi‐isotropic antenna

A dualband quasi-isotropic antenna is presented. It is based on the split-ring-resonators (SRRs), which provide a quasi-isotropic radiation pattern with an electrically small size. For the dualband operation, the SRRs are placed orthogonally to reduce the mutual coupling between the elements. A folded dipole structure is applied to the SRR, therefore, the input impedance at each band can be easily tuned. Both simulated and measured results are presented. The results show dualband operation (792 and 1124 MHz), high efficiency (higher than 86 and 85.5%), compact size (ka = 0.47 at 792 MHz), moderate gain deviation (4.42 and 5.76 dB) with simple direct feed.

The treatment effect of grade repetitions

ABSTRACTThis paper estimates the treatment effect of grade repetitions in French junior high schools, using a value-added test score as outcome and quarter of birth as instrument. With linear two-stage least squares, local average treatment effect is estimated at around 1.6 times the standard deviation of the achievement gain. With non-linear full-information maximum likelihood, average treatment on the treated ranges between one and one-quarter of the standard deviation of the outcome. Grade repetition in junior high school is also shown to increase the probability of graduating from junior high school by 2.5 probability points.

Effects of gestational weight gain and breastfeeding on postpartum weight retention among women in the BRISA cohort

This study analyzed the effects of gestational weight gain and breastfeeding on postpartum weight retention. The study followed 2,607 women from the BRISA cohort. The variables were age, socioeconomic status, parity, pre-gestational body mass index, gestational weight gain, duration of maternal breastfeeding, length of postpartum follow-up, and postpartum weight gain. Structural equation modeling was used to evaluate the total, direct, and indirect effects of the explanatory variables on postpartum weight retention. An increase of one standard deviation in gestational weight gain corresponded to a significant increase of 0.49 standard deviations in postpartum weight retention (p < 0.001). An increase of one standard deviation in duration of breastfeeding corresponded to mean decrease of 0.10 standard deviations in postpartum weight retention (p < 0.001). Independently of pre-gestational BMI, gestational weight gain is a risk factor and duration of breastfeeding is a protective factor against postpartum weight retention.