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HRES (Hybrid Renewable Energy Systems) has been designed because of the increasing demand for environmentally friendly and sustainable energy. In this study, an Improved Subtraction-Average-Based Optimizer (ISABO) is presented for optimizing the HRES system by wind power, fuel cells, and solar energy. The suggested approach, by introducing adaptive mechanisms and enhancing processes, improves the performance of the traditional subtraction-average-based optimization. Optimization aims to provide reliable and efficient energy while lowering system expenses. The efficacy of ISABO is evaluated for this goal and compared with other optimization techniques. According to the findings, The ISABO algorithm, when equipped with adaptive mechanisms, surpasses conventional optimization techniques by achieving a 12 % decrease in Net Present Cost (NPC) and Levelized Cost of Electricity (LCOE) along with a 45 % cost reduction in electrolyzers. Through simulations, it has been shown that the ISABO algorithm ensures the lowest average NPC at $1,357,018.15 while also upholding system reliability with just a 0.8 % decline in Load Point Supply Probability (LPSP) in the event of a PV unit failure. This research validates that hybrid PV/wind/fuel cell systems present superior cost-effectiveness and reliability, thereby opening doors for more economical renewable energy solutions. The study reveals hybrid PV/wind/fuel cell systems are more cost-effective than purely wind, PV, or fuel cell systems. This advancement in HRES design and optimization techniques will enable more cost-effective renewable energy options.

The focus of this work is to investigate the ticking noise produced by the vibro-impacts between piston pin and connecting rod small head bearing. Numerical calculation and experimental verification methods were adopted and a novel method to control this intermittent noise was proposed. The dynamic model of crankshaft connecting rod piston with full floating piston pin was established and the essence of piston pin ticking was analyzed. The occurrence time of the ticking corresponded to the crankshaft angle when the resultant force of piston pin passed through the 0 axis. At the moment of impact, the peak hydraulic pressure of lubricating oil was found to be proportional to the impact strength. In order to suppress this noise, the oil groove on the bearing was designed considering the minimum oil film. After adding the oil groove, the impact intensity was significantly reduced and the noise was even eliminated. The calculated results were in good agreement with the experimental tests, and the research of this work provided a reference for controlling the ticking noise of piston pin.

To reduce the heating of the Terfenol-D rod and evaluate its working efficiency, six kinds of Terfenol-D rods were designed, and the temperature field of the rods was simulated and calculated using the finite element method to obtain the temperature distribution. The results showed that the untreated rod had the highest temperature; the temperature was higher in the middle and lower at both ends; higher on the outer diameter surface; and lower on the inside. When compared to the untreated rod, the temperatures of sliced rods and slit rods decreased, and the temperature of sliced rods was lower than that of slit rods; the temperature of slit rods was higher in the middle and lower at both ends; the temperature distribution of sliced rods was more uniform relatively; the slice treatment rod had the lowest temperature and the best heat suppression effect. Three structural rods were chosen and manufactured from a total of six that were tested. It shows that the temperature of all rods was higher in the middle and lower at both ends after 30 min of operation. The actual temperature of untreated rod was 34 °C, the actual temperature of radially slit rod was 32 °C, and the actual temperature of sliced rod at both ends was 28 °C. The tested temperature distributions of three rods agreed with the calculated ones.

Biomarker discovery and its clinical use have attracted considerable attention since early cancer diagnosis can significantly decrease mortality. Cancer biomarkers include a wide range of biomolecules, such as nucleic acids, proteins, metabolites, sugars, and cytogenetic substances present in human biofluids. Except for free-circulating biomarkers, tumor-extracellular vesicles (tEVs) and circulating tumor cells (CTCs) can serve as biomarkers for the diagnosis and prognosis of various cancers. Considering the potential of tumor biomarkers in clinical settings, several bioinspired detection systems based on nanotechnologies are in the spotlight for detection. However, tremendous challenges remain in detection because of massive contamination, unstable signal-to-noise ratios due to heterogeneity, nonspecific bindings, or a lack of efficient amplification. To date, many approaches are under development to improve the sensitivity and specificity of tumor biomarker isolation and detection. Particularly, the exploration of natural materials in biological frames has encouraged researchers to develop new bioinspired and biomimetic nanostructures, which can mimic the natural processes to facilitate biomarker capture and detection in clinical settings. These platforms have substantial influence in biomedical applications, owing to their capture ability, significant contrast increase, high sensitivity, and specificity. In this review, we first describe the potential of tumor biomarkers in a liquid biopsy and then provide an overview of the progress of biomimetic nanostructure platforms to isolate and detect tumor biomarkers, including in vitro and in vivo studies. Capture efficiency, scale, amplification, sensitivity, and specificity are the criteria that will be further discussed for evaluating the capability of platforms. Bioinspired and biomimetic systems appear to have a bright future to settle obstacles encountered in tumor biomarker detection, thus enhancing effective cancer diagnosis.

With the continuous development of deep learning, its drawbacks are also beginning to appear. As an alternative to deep learning, broad learning is emerging. However, the level of broad learning model is shallow, so feature learning is not sufficient. In order to solve two problems of small samples whose dimensions are not very high in network model training, it cannot be adequately trained in the deep learning model and the features of input data cannot be fully learned in the broad learning model. This paper attempts to add a hidden layer on the enhancement nodes of the broad learning model and do shallow learning for the enhanced features to learn the hierarchical features again. This improved broad learning model also provides a new idea for solving the problem of small samples. From the perspective of regression and classification, this paper proves that for small samples whose dimensions are not very high, the effect of the improved broad learning model is better than that of the original broad learning model and also proves that the improved broad learning model has a good ability of application. This shows that the broad learning model based on enhanced features learning has the necessity and feasibility of further research.

By developing new mathematical descriptions of 4q (integer q 2) quadrature amplitude modulation (QAM) constellation, a novel construction producing 4q-QAM complementary sequences (CSs) of length 2m (integer m 2) is presented. The proposed sequences include the known 4q-QAM CSs constructed from Cases Ito III constructions, proposed by Li, as special cases. For 16-QAM CSs, the number of the resultant sequences is determined precisely. New sequences have a larger family size so as to increase the code rates. When used in orthogonal frequency-division multiplexing (OFDM) systems, new sequences possess the same peak envelope power (PEP) upper bounds as those of the known sequences referred to above.

Liquid biopsy has the great potential of detecting early diseases before deterioration and is valued for screening abnormalities at early stage. In oncology, circulating DNA derived from shed cancer cells reflects the tissue of origin, so it could be used to locate tissue sites during early screening. However, the heterogenous parameters of different types limit the clinical application, making it inaccessible to encompass all the cancer types. Instead, for reproducible scenario as pregnancy, fetal cell-free DNA has been well utilized for screening aneuploidies. Noninvasive and convenient as is, it would be of great value in the next decades far more than early diagnosis. This review recapitulates the discovery and development of tumor and fetal cell-free DNA. The common factors are also present that could be taken into consideration when collecting, transporting, and preserving samples. Meanwhile, several protocols used for purifying cell-free DNA, either classic ones or through commercial kits, are compared carefully. In addition, the development of technologies for analyzing cell-free DNA have been summarized and discussed in detail, especially some up-to-date approaches. At the end, the potential prospect of circulating DNA is bravely depicted. In summary, although there would be a lot of efforts before it’s prevalent, cell-free DNA remains a promising tool in point-of-care diagnostic medicine.

A square flat-plate radiator driven by a longitudinal vibrator at the resonant frequency of its fourth-order natural vibration mode at its center for the generation of highly directional ultrasonic radiation in air is studied herein. The radiator was able to create a bending vibration mode whose four straight nodal lines were located at a 45° angle on each side. To obtain highly directional sound, the surrounding area of the four right isosceles triangles formed by a nodal line and two sides is modified to be raised one by half the wavelength of sound radiated in the propagation medium so that surface elements vibrate in phase. Then, the relation among the frequencies, nodal lines of the rhombus mode, and geometrical dimensions of the radiator is determined. The calculated directivity pattern of the stepped-plate radiator is equivalent to that of its corresponding theoretical piston, i.e., a stepped plate is a piston-like radiator. Results show that the measured vibrational-mode shape of the stepped-plate radiator is consistent with the calculated one, and the calculated directivity pattern is almost similar to the measured one.

Each pixel in the hyperspectral unmixing process is modeled as a linear combination of endmembers, which can be expressed in the form of linear combinations of a number of pure spectral signatures that are known in advance. However, the limitation of Gaussian random variables on its computational complexity or sparsity affects the efficiency and accuracy. This paper proposes a novel approach for the optimization of measurement matrix in compressive sensing (CS) theory for hyperspectral unmixing. Firstly, a new Toeplitz-structured chaotic measurement matrix (TSCMM) is formed by pseudo-random chaotic elements, which can be implemented by a simple hardware; secondly, rank revealing QR factorization with eigenvalue decomposition is presented to speed up the measurement time; finally, orthogonal gradient descent method for measurement matrix optimization is used to achieve optimal incoherence. Experimental results demonstrate that the proposed approach can lead to better CS reconstruction performance with low extra computational cost in hyperspectral unmixing.

This paper presents a new scheme to improve the performance of finger-vein identification systems. Firstly, a vein pattern extraction method to extract the finger-vein shape and orientation features is proposed. Secondly, to accommodate the potential local and global variations at the same time, a region-based matching scheme is investigated by employing the Scale Invariant Feature Transform (SIFT) matching method. Finally, the finger-vein shape, orientation and SIFT features are combined to further enhance the performance. The experimental results on databases of 426 and 170 fingers demonstrate the consistent superiority of the proposed approach.

To prevent important items from being replaced by a forgery, an ultrasonic fingerprint identification algorithm is proposed and an identification program is developed. A virtual prototype for the ultrasonic identification of ceramics is developed based on an ultrasonic detection card. This virtual prototype allows for the simultaneous transmission and acquisition of signals. Numerous experimental tests were conducted using this virtual prototype. The results demonstrate that the virtual prototype achieves accurate identification of ceramics. This virtual prototype lays a good foundation for the development of intelligent, automated, integrated, and miniaturized ultrasonic identification systems. [ABSTRACT FROM AUTHOR]

To efficiently use Terfenol-D rods, six of its structures were studied. Finite element analysis was used to estimate and compare the hysteresis, eddy current, and coil resistance losses of the six Terfenol-D rods. The loss factors of the rods were calculated and analyzed. Furthermore, three structures of Terfenol-D rods were manufactured, and the loss factors of the rods were measured. The results showed that an untreated rod had the largest hysteresis and eddy current losses on the outer diameter surface, and the overall hysteresis loss of the rod was the smallest. Compared with the untreated rod, the eddy current and hysteresis losses on the outer diameter surface of sliced and slit rods reduced, the overall hysteresis loss of sliced and slit rods increased, and the overall eddy current loss of sliced rods reduced; the hysteresis and eddy current losses on the surface of the sliced rods were less than that of the slit rods, and the overall eddy current loss of the sliced rods was less than that of the slit rods; moreover, the eddy current loss of each rod was larger than its hysteresis loss. The numerical calculation values of the coil resistance loss basically agreed with the theoretical calculation values. The finite element simulation calculation values of the loss factors of the Terfenol-D rods agreed with the experimental test values. [ABSTRACT FROM AUTHOR]