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Development of a closed fly wheel based energy system is a concept for generating energy free that is emission free like the renewable energy sources. It comprises a fly wheel 315kg, 2.5Hp 220volts DC motor,10Hp 250volt Alternator, locally developed hub powered with pump for cooling and hydrodynamic lubrication of the flywheel shaft, charge controller, and smart system. The concept of the design and development of a fossil fuel free generator is driven from the high energy stored in fly wheels. An ecofriendly power generation is needed to reduce emissions that have led to the well-discussed global warming and depletion of ecosystem. The momentary motion of any fly wheel is a function of its mass and its velocity as it affect the duration of its rotation before coming to rest. The interconnectivity among the flywheel, generator, a battery and a DC motor can lead production of a reasonable amount of Electrical Energy. Inertia laws and momentum were used in the design of the flywheel. The use of charging controllers and battery management system (BMS) as well as rectifier are used to maintain steady supply and battery life Generation principles, identification of areas of loses, power stability, energy bank, electronic energy booster (fondly known as electronic gear) and smart system for energy management and sustainability.

Due to the accelerated development of social science and technology, the development of modern science and technology is in urgent need of a large number of innovative scientific and technological talents, and the CDIO teaching mode based on the combination of practice and theory is receiving more and more attention in undergraduate teaching. CDIO teaching mode is a new education mode that has achieved remarkable results in the current higher engineering education. It always aims to train a new generation of international modern engineers. This paper introduces the proposal, background and application of CDIO, and embodies the effect of combining with the talent training program of biopharmaceutical engineering.

We performed a meta-analysis to evaluate the effect of negative pressure wound therapy compared with conventional wound dressings on closed incisions in orthopaedic trauma surgery. A systematic literature search up to October 2021 was done and 12 studies included 3555 subjects with closed incisions in orthopaedic trauma surgery at the start of the study: 1833 of them were provided with negative pressure wound therapy and 1722 were conventional wound dressings. They were reporting relationships about the effect of negative pressure wound therapy compared with conventional wound dressings on closed incisions in orthopaedic trauma surgery. We calculated the odds ratio (OR) and mean difference (MD) with 95% confidence intervals (CIs) to assess the effect of negative pressure wound therapy compared with conventional wound dressings on closed incisions in orthopaedic trauma surgery using the dichotomous and continuous methods with a random or fixed-effect model. Negative pressure wound therapy had significantly lower deep surgical site infection (OR, 0.65; 95% CI, 0.48-0.88, P = .005), superficial surgical site infection (OR, 0.23; 95% CI, 0.11-0.49, P = .31), and wound dehiscence (OR, 0.41; 95% CI, 0.21-0.80, P = .009) compared with conventional wound dressings in subjects with closed incisions in orthopaedic trauma surgery. However, negative pressure wound therapy had no significant effect on the length of hospital stay (MD, 0.29; 95% CI, -2.00- 2.58, P = .80) compared with conventional wound dressings in subjects with closed incisions in orthopaedic trauma surgery. Negative pressure wound therapy had significantly lower deep surgical site infection, superficial surgical site infection, and wound dehiscence; however, negative pressure wound therapy had no beneficial effect on the length of hospital stay compared with conventional wound dressings in subjects with closed incisions in orthopaedic trauma surgery. Further studies are required to validate these findings.

The C2 domain family proteins in plants has been recently shown to be involved in the response to abiotic stress such as salt and drought stress. However, less information on C2 domain family members has been reported inThe online version contains supplementary material available at 10.1007/s12298-022-01222-3.

In this paper, a sparse estimation algorithm for the radar target range and direction under strong mainlobe blanket jamming conditions is presented. This algorithm can effectively suppress multiple strong mainlobe blanket jammings (multi-MLJs) and extract the information about target distance and direction. First, the space domain adaptive processing for the received signal in each row (or column) is adopted to suppress multi-MLJs. Second, the sparse Bayesian learning is employed to obtain the information of the target distance and elevation (or azimuth). In addition, the proposed method still has an effective performance under the error condition and the applicable conditions of the new algorithm based on the performance analysis are provided in this paper.

Major abiotic stresses such as drought and salinity affect the growth and yield of crops. NAC (NAM, ATAF1/2, and CUC2) is a plant-specific gene family that has been demonstrated to contribute to responses and adaption to abiotic stress in plants. The specific NAC transcription factors (TFs) that play important roles in the response to abiotic stress in sorghum are unknown. Here, we characterized a sorghum TF, SbNAC2, that can be strongly induced by abiotic stresses, including polyethylene glycol (PEG)-simulated dehydration stress treatment, salt treatment, and 4 °C chilling. Knockdown of SbNAC2 in sorghum seedlings by virus-induced gene silencing (VIGS) weakened the drought tolerance of plants. Heterologous overexpression of SbNAC2 in Arabidopsis and rice can induce plant antioxidant enzyme activity under abiotic stress conditions. Furthermore, SbNAC2 directly activates the expression of a stress responsive AP2/ERF type TF gene, SbAP37, by binding to the TTNCGTA motif of its promoter. These results indicate that SbNAC2 functions as a potentially important regulator in response to abiotic stresses and that it may possibly be used for molecular breeding to enhance crop yields under adverse environmental conditions.

ObjectivesThis study aimed to evaluate the association between early-life exposure to the Great Chinese Famine (1959–1961) and the prevalence of poor physical function in midlife.DesignA population-based historical prospective study was performed as part of a wider cross-sectional survey. Exposure to famine was defined by birthdate, and participants were divided into non-exposed group, fetal-exposed group and infant-exposed group.Setting and participantsA total of 3595 subjects were enrolled into the study from the China Health and Retirement Longitudinal Study (CHARLS) 2015 based on random selection of households that had at least one member aged 45 years old and older in 28 provinces of mainland China.Main outcome measuresPhysical function status was assessed by a six-item self-report on the Barthel scale which rated basic activities of daily living (BADL).Results743 (20.7%) out of all participants were exposed to the Great Chinese Famine in their fetal periods, while 1550 (43.1%) participants were exposed at the age of an infant. The prevalence of poor physical function in the non-exposed group, fetal period-exposed group and infant period-exposed group were 12.3%, 15.5% and 17.0%, respectively. Among males, after stratification by gender and severity of famine, the prevalence of poor physical function in the fetal period was significantly higher (OR 2.40, 95% CI 1.18 to 4.89, p=0.015) than the non-exposed group in severely affected areas, even after adjusting for the number of chronic diseases, place of residence, smoking and alcohol drinking habits, marital status, educational level and body mass index. A similar connection between prenatal and early postnatal exposure to the Great Chinese Famine and the prevalence of poor physical function in midlife, however, was not observed from female adults.ConclusionsMales who were exposed to the Great Chinese Famine (1959–1961) present considerably decreased physical function in their later life.

Basis pursuit of sparse decomposition is adopted to discriminate and identify the target echo with two kinds of mainlobe jamming named time-delay repeater jamming and smeared spectrum (SMSP) jamming, which can produce multiple false targets. The main idea is to extract their pulsed differences. The signal model is first transformed to an underdetermined matrix equation, the dictionary is constructed by the function form of the target echo, and then the matrix equation is solved by replacing the l 0 norm problem via the l 1 norm problem. The identification of time-delay repeater jamming and the target echo is by the difference of the pulse width. Identifying SMSP jamming and the target echo is by the difference of the chirp rate. The proposed algorithm is particularly relevant to the case that the signals are overlapped. Finally, simulation results demonstrate the efficacy of the proposed method and they show that the method outperforms the conventional time–frequency representation method.

According to the idea of cognitive radar, the frequency increment in frequency diverse array (FDA) needs to be adaptively adjusted to the changed environments so that the FDA’s anti-jamming performance always is optimal. The nonlinear frequency increment can eliminate the traditional FDA beam’s periodicity in range and form a single peak beam, which is helpful to the detection of the target. In view of this, this paper presents a nonlinear FDA optimal frequency increment selection method. 2It derives the intrinsic relationship between the output SINR and the frequency increment. Within a coherent processing interval (CPI), the frequency increment can be adaptively selected corresponding to the minimum modulus of the array weight vector and then it is fed back to the transmitter and applied to the next CPI. Both the theories and simulations show that FDA has a better anti-interference ability after taking optimal frequency increment by this method.

Only in the presence of sidelobe jamming (SLJ), can the conventional adaptive monopulse technique null the jamming effectively and maintain the monopulse angle estimation accuracy simultaneously. While mainlobe jamming (MLJ) exists, the mainlobe of adaptive pattern will subject to serious distortion, which results in a failure of detecting and tracking targets by monopulse technique. Therefore, a monopulse angle estimation algorithm based on combining sum-difference beam and auxiliary beam is presented. This algorithm utilizes both high gain difference beams and high gain auxiliary beams for cancelling the mainlobe jammer and multiple sidelobe jammers (SLJs) while keeping an adaptive monopulse ratio. Theoretical analysis and simulation results indicate that the serious invalidation of monopulse technique in MLJ and SLJs scenarios is resolved well, which improves the monopulse angle accuracy greatly. Furthermore, the proposed algorithm is of simple implementation and low computational complexity.

It is common to use Moving Target Detection (MTD) to compete with passive clutter. When there are jamming and clutter at the same time, it is necessary to apply Adaptive Sidelobe Canceller (ASLC) before MTD. However, the weight noise caused by ASLC brings about the large surplus of clutter in the MTD process, which affects the performance of MTD. Therefore, two methods, diagonal loading based (DL-based) ASLC and MTD processing ahead of ASLC, are proposed in this paper to solve this problem. Simulation results indicate that the proposed methods can improve the performance of MTD.

In this paper, to suppress the digital radio frequency memory (DRFM) false target jamming, we introduce a jamming recognition-based method. The method first extracts mixed target and jamming samples, then computes adaptive weights by subsections of mixed samples, finally recognizes the jamming samples according to the adaptive power residue (APR) criterion. Numerical examples are provided which verify the effectiveness of the proposed method.

The basis pursuit algorithm of sparse decomposition is used to recover and discriminate the target echo and the jamming signal which have different time-delay and pulse width. The key is to construct an atomic dictionary. The recoveries in both the noiseless case and in the noisy case are considered. The noiseless case adopts linear programming. The noisy case adopts quadratic programming. Since the recovery is sensitive to the noise, the solution to the noisy case is unstable. More importantly, densely false targets, including the case that two signals are overlapped in the temporal domain, can also be recovered. Finally, simulations verifies the results.

When a mainlobe jamming (MLJ) exists, the mainlobe of adaptive pattern will be subject to serious distortion, which results in a failure of monopulse angle estimation performance. And as we all know, phased array radar often has tens of thousands of elements. If we use general adaptive processing, it needs to place a receiving channel on each element. However, it results in much complex system, high cost of hardware and the difficulty to meet the real-time requirement. Therefore, we need adaptive dimension-reduced processing based on perfect monopulse technology. Thus, an adaptive monopulse algorithm based on combining sum-difference and auxiliary beam at subarray level for anti-jamming is presented in this paper. This new algorithm can not only suppress the MLJ and sidelobe jamming (SLJ)s while maintaining monopulse ratio undistorted, but also successfully solves the problem from phased array system to make it easy for implement in engineering.

The conventional adaptive beamforming will lead to a severe distortion of monopulse ratio curve in the presence of mainlobe jamming(MLJ), which results in a failure of angle estimation and tacking of a target. This paper presents an constrained adaptive sum-difference monopulse algorithm based on penalty function. This adaptive algorithm can not only suppress the MLJ while maintaining monopulse ratio undistorted, but also lower the sidelobe levels of adaptive pattern. Especially, the sidelobe of difference beam can be suppressed very well.

The conventional adaptive beamforming will lead to a severe distortion of monopulse ratio curve in the presence of mainlobe jamming(MLJ), which results in a failure of angle estimation and tacking of a target. An adaptive algorithm based on multipoint constraint is presented in this paper. This technique can suppress the MLJ while maintaining monopulse ratio undistorted, which greatly improves the performance of angular estimation.

PD mode is usually adopted in airborne phased array radar. However, there are two problems which severely degrade the performance of adaptive beamforming. One is the ground clutter return in the training data, the other is the target return in the training data. Therefore, in this paper, the two problems above are analyzed in detail, and then the methods suitable for engineering realization are presented. Computer simulation results are presented for illustration.

To avoiding two-dimensional search for the incoming angle of jamming while constructing two-dimensional auxiliary beams, an adaptive-adaptive beamforming algorithm of planar array based on one-dimensional auxiliary beam is presented in this paper. Owing to only need to estimate one-dimensional spatial angle of jamming, computational complexity of searching for the incoming angle of jamming can be reduced greatly. Thus, the approach is fit for engineering implementation. Computer simulations demonstrate the validity finally.

By constructing an extended interference covariance matrix and the auxiliary beamspace，an improved adaptive-adaptive array processing method is presented based on nulls widening in this paper. It resolves an issue that the adaptive-adaptive algorithm can’t reject interference effectively when the perturbation or the rapid motion of jammers occurs, which improves robustness greatly. As a partially adaptive beamforming algorithm, it is more suitable for the practical engineering application. Computer simulations demonstrate the validity of the approach.

The direct data domain least squares (D3LS) approach using a single snapshot is capable of handling a highly nonstationary environment, particularly in the case of blinking jammers and coherent jammers. In addition to advantages, however, there exist some drawbacks such that the degrees of freedom are reduced, the main beam of the array antenna is often deviated from the direction of the desired signal and the sidelobe level rise relatively high. Hence, this paper addresses a modified D3LS method on a snapshot-by-snapshot basis to overcome these disadvantages. The simulation experiments demonstrate the effectiveness of the proposed approach.

Blanket deception jamming is characteristic of both noise jamming and deception jamming, which cause some traditional anti-jamming measures invalid such as sidelobe canceling and sidelobe blanking and so on. In this work, an approach of time-space cascade adaptive sidelobe canceling based on jamming sample recognition is presented. Even when the number of jammings is more than that of auxiliary channels, the suppression results is still very good. The computer simulations demonstrate the validity.

In this paper, the performance of mutual coupling compensation in adaptive arrays is studied. It is indicated that the adaptive array after mutual coupling compensation can suppress interference thoroughly. However, the output power of noise changes with the direction of desired signal, which causes the degradation of the output signal-to-interference-plus-noise ratio (SINR). Therefore, the thermal noise is mainly responsible for the output SINR degradation after mutual coupling compensation. This conclusion derived from the paper is expected to be valuable for the engineering application of an adaptive array. The simulation results demonstrate further the conclusions.