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Background Prior research has confirmed the efficacy of exercise training (ET) in patients with prediabetes. However, whether the effectiveness of a combination of exercise and psychological intervention (EP) is better than ET alone in prediabetes in terms of physiological function, psychological status and glycometabolism has rarely been investigated. Methods Forty newly diagnosed prediabetes patients (65.3 ± 8.1 years) took part in the study. Subjects were divided into a pure ET group and a combined EP group. Interventions were conducted in 40–50-min sessions twice weekly for 32 weeks. Physiological, psychological and biochemical indicator measurements were taken after pre-, mid- and post-interventions, respectively. Results The main finding confirmed a significant improvement in systolic blood pressure, diastolic blood pressure (DBP) and heart rate, high-density lipoprotein, fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1c) from pre- to mid- and post-test differentially in both groups (P Conclusion Our results suggest that EP might be a promising method lead to more apparent long-term effects on glycometabolism and psychological status for prediabetes patients. Other domains were improved by both interventions, but no typical pattern could be identified. Its underlying mechanisms need further study, and directions for future research are suggested.

Helicobacter pylori (H. pylori) is one of the main factors that cause gastric lesions. The lotus leaf is an edible plant used in traditional Eastern medicine. This study evaluates the intervention effects of lotus leaf flavonoids (LLF) on gastric mucosal lesions in mice infected with H. pylori and explores their mechanism of action. High-performance liquid chromatography analysis reveals that LLF contain kaempferitrin (kaempferol-3,7-dirhamnoside), hypericin, astragalin (kaempferol-3-glucoside), phlorizin, and quercetin. LLF can reduce the number of gastric mucosal lesions and tissue lesions in mice with H. pylori-induced gastric lesions. LLF can increase the levels of somatostatin and vasoactive intestinal peptide in the serum of mice with gastric lesions and decrease the levels of substance P and endothelin-1 to inhibit gastric lesions. LLF can also reduce the levels of interleukin (IL)-6, IL-12, tumor necrosis factor (TNF)-α, and interferon-gamma cytokines in the serum of mice with gastric lesions. Using a quantitative polymerase chain reaction assay it can be seen that LLF can downregulate mRNA expressions of TNF-α, IL-1β, myeloperoxidase, keratin (KRT) 16, KRT6b, and transglutaminase 3 epidermal in the gastric tissues of mice with gastric lesions. Western blot analysis indicates that LLF can downregulate the protein expressions of caspase-1, Nod-like receptor protein 3, IL-1β, TNF-α, and Toll-like receptor 4 in the gastric tissues of mice with gastric lesions. LLF have beneficial effects on gastric lesions induced by H. pylori. Meanwhile LLF is more active in competition with ranitidine. LLF represent an active substance that can inhibit H. pylori-induced gastric lesions. The flavones of LLF may enhance the inhibition of gastric mucosal lesions by promoting the interaction between the compounds.

Accurate and reliable fault detecting plays a key role in application of grid-connected wave power generation systems. This study presents a novel IoT-based approach to condition monitoring of the wave power generation system, which has faster operating rate and lower hardware requirement. The compressed sensing (CS) method is adopted to compress the data, which aims to reduce the data uploaded to cloud platform; and then, the extreme learning machine (ELM) algorithm is used to achieve the condition monitoring of wave power generation system in cloud platform. In order to validate the effectiveness of the proposed method, the IoT-based wave power generation condition monitoring system test platform is established. The experiment results illustrate the high efficiency and reliability of proposed method. The proposed method has a potential of practical applications.

Tidal current turbine, as an effective technical means to contribute to all around the world achieving targets for reducing greenhouse gas emissions and the production of renewable energy, has obtained great concern. It was established that more than 94 TWh per year could be generated in the developable sea area. Many types of tidal current turbine structures and control methods have been proposed, however, the possible increase in power generation must consider parameters such as reliability, cost, and complexity of the control system. The paper presents a review on configuration and control methods of tidal current turbines. The configuration and control methods of tidal current turbines are classified, described and compared, especially for horizontal axis tidal current turbines. Horizontal axis tidal current turbine is more widely used, due to high energy conversion efficiency. Different configuration and corresponding control methods have their advantages and disadvantages, which affect efficiency, maintenance requirements, and the cost of electricity from tidal current.

In order to achieve effective dust suppression during coal cutting process in a fully-mechanized coal mining face by using coal cutter dust removal fans, this study first conducted numerical simulations on the airflow-dustmigration rules. Then, by combining simulation results with experimental measurements and field tests, a novel hydraulic axial-flow dust coal cutter removal fan was developed. Simulation results demonstrated that, during the coal cutting process, high-concentration dust clusters exceeding 1000 mg/m3 were produced 0–20 m away from the coal cutter on the leeward side, which then spread to the operating space along the footway. After using dust removal fans, the concentration of the dust clusters on the leeward side of the coal cutter was reduced to below 500 mg/m3. The dust removal fans were then applied to the 3up705 fully-mechanized coal mining face at seven-five Coal Mine for field measurements. According to the measured results, the use of these dust removal fans can effectively reduce the dust concentration in the operating region around the coal cutter, and the dust removal rates of total dust and respirable dust reached up to 66.5% and 61.8%, respectively. Therefore, the dust removal fans performed well in terms of dust suppression in fully-mechanized coal mining faces.

BackgroundsRectal GISTs are relatively rare and surgical resection is the potential curative treatment for rectal GISTs. However, limited studies addressing the outcomes of minimally invasive surgery for rectal GIST. MethodsA total of 32 rectal GIST patients were retrospective from January 2010 to December 2019 at Xiangya hospital Central South University. The demographic and clinicopathologic data were supplemented by our clinic and pathologic system. Selection bias was eliminated using the propensity score matching (PSM) methods ResultsAfter PSM, 22 patients were finally enrolled in our cohorts, with 11 patients in minimally invasive surgery (MIS) group and 11 patients in open surgery(OPEN) group randomly matched (1:1) by age, gender, body mass index, tumor size, tumor distance above the anal edge. MIS group recived a shorter operating time (108.45±31.56min vs 136.18±28.58min, P=0.043) and lesser blood less(67.27±54.97mL vs 194.55±115.96mL, P=0.004) than OPEN group during the operation. Besides, the MIS group seemed to gain a shorter time to resume borborygmus after operation, flatus passage, resuming oral diet, and hospital stay, but no significantly statistic difference(P＞0.05). Moreover, no differences in rate of 1-year, 3-year, and 5-year Progression Free Survival and overall survival was found between two groups.ConclusionCompared with open surgery, minimally invasive surgery benefits a shorter operating time and lesser blood less in operation in rectal GISTs. Moreover, similar oncologic outcome was found both in minimally invasive surgery and open surgery in rectal GISTs.

Accurate tidal current prediction plays a critical role with increasing utilization of tidal energy. The classical prediction approach of the tidal current velocity adopts the harmonic analysis (HA) method. The performance of the HA approach is not ideal to predict the high frequency components of tidal currents due to the lack of capability processing the non-astronomic factor. Recently, machine learning algorithms have been applied to process the non-astronomic factor in the prediction of tidal current. In this paper, a tidal current velocity prediction considering the effect of the multi-layer current velocity method is proposed. The proposed method adopts three machine learning algorithms to establish the prediction models for comparative investigations, namely long-short term memory (LSTM), back-propagation (BP) neural network, and the Elman regression network. In the case study, the tidal current data collected from the real ocean environment were used to validate the proposed method. The results show that the proposed method combined with the LSTM algorithm had higher accuracy than both the commercial tidal prediction tool (UTide) and the other two algorithms. This paper presents a novel tidal current velocity prediction considering the effect of the multi-layer current velocity method, which improves the accuracy of the power flow prediction and contributes to the research in the field of tidal current velocity prediction and the capture of tidal energy.

The Fe-catalyzed Fischer-Tropsch (FT) synthesis reaction is the core of the coal-to-liquids (CTL) process, which is an efficient route to convert coal into liquid fuels via synthesis gas (a mixture of CO and H2). Conventional Fe-based FT catalysts convert typically 30% of the feed CO to undesirable CO2during the FT step. A decrease of CO2production in FT units can reduce the profitability of the overall CTL process. In this context, we synthesized phase-pure ϵ-Fe-carbide FT catalysts by careful control of the pretreatment and carburization conditions starting from Raney Fe. The resulting phase-pure Fe-carbide exhibits a low CO2selectivity during the Fischer-Tropsch reaction. The developed preparation method can be applied to supported Fe catalysts and does not require expensive starting chemicals. The purity and durability of as-synthesized phase-pure ϵ-Fe-carbide catalyst under FT conditions were characterized in detail by in situ characterization techniques. A bulk phase-pure ϵ-Fe-carbide catalyst operated at 23 bar, 235 °C and a H2/CO ratio of 1.5 shows stable performance with no deactivation during a 150 h pilot test. The catalyst is free of primary CO2formation and presents reduced secondary CO2formation compared to conventional Fe-based FT catalysts. These findings contribute to the development of new Fe-based FT catalysts for CTL processes.

The image collected in the paper defect detection system has lateral gray unevenness. Based on the theory of geometrical optical irradiance, this paper studies the application technology around the uniform distribution of illuminance on the paper detected by the light source module of the paper defect detection system. According to the Sparrow's criterion, the optimal distance function between the LED beads in the light source module is determined. From the perspective of machine vision, the power optimization function of the lamp bead at different positions in the light source array is determined by experimental method. The improvement effect of the light source was verified by using the image gray uniformity index. The experimental results show that the optimization scheme can increase the gray uniformity of the acquired image to 98.61%, which is greatly improved compared with 57.80% before optimization. This effectively improves the image quality of the paper and reduces the difficulty of image processing in the later stage, which is expected to improve the execution efficiency of the application.

The amplitude and distribution of single-phase ground fault current in the original distribution network are affected by the access of distributed generation (DG). In addition to the access capacity of the DG, the influence of the neutral point grounding coordination mode and fault point location between the distribution network side and the DG side on the fault current is more significant and complex. The single-phase grounding fault of the DG after it is tied to the 10kV distribution network is analyzed, and the fault current amplitude and its distribution under different coordination modes of the distribution network side and the neutral point grounding of the DG side are discussed. The simulation results show that the change of the distribution network side grounding mode has little effect on the single-phase grounding fault current, which is mainly reflected in the change of the fault current amplitude, while the change of the distribution generation side grounding mode causes the change of the fault current amplitude and also affects the distribution of the fault current, which brings difficulties to the relay protection setting.

The polish mechanisms for composite material box is produced for polishing box within demanding error range, it is made up of gear system, shaft systems and other transmission parts, the clearance and eccentric in the assembly lead to motion error in the polish mechanism; hence, the error reliability of polish mechanisms should be investigated. The error distributions follow normal distribution, the parameter are defined according to the multi-object software ADAMS simulation experiments results. The position accuracy reliability analysis bases on the Monte-carol method to estimate reliability of the polish equipment. Error distribution parameters are calculated with ADAMS simulation experiments instead of the real experiment, which can spare the experimental cost and time and makes it easy to predict reliability with little consumption. The error analysis focuses on the gear system and shaft system mainly, the other factor from other parts are neglected due to their little influence on the error, the reduced analysis benefits to the rapid obtaining reliability results.

This letter presents a novel wearable thermoelectric generator (TEG) device for powering electronics by harvesting human body heat. The structural design of the TEG device consists of 12 thermoelectric modules, which are connected by copper strips electrically in series and thermally in parallel. A flexible printed circuit board with special hollows’ design is utilized as the bottom electrodes and substrate to enhance the flexibility of the device. The fabrication procedure to make this TEG device is then described. The hot- and cold-sides of TEG are soldered by a thin layer of Sn96.5Ag3Cu0.5 and Sn42Bi58, respectively. Therefore, the developed TEG device features both high flexibility and excellent performance for heat harvesting. Experimental characterization results demonstrated that the TEG device can achieve 23 μ W power and 4.75 μ W/cm2 power density at a temperature difference of 35 K. After wearing on human wrist, this TEG device can generate an open-circuit voltage of 10.5 mV, and the ability of using this TEG for powering a light emitting diode has been demonstrated. Results indicated that the developed wearable TEG device could be used for powering of wearable electronics and/or sensors.

The facial expression recognition is a hot research subject of computer vision, which causes a broad range of application in the domains of human-computer interaction, security and robotics. However, due to the influence of illumination and posture, real-time facial recognition is still a challenge. In this work, a facial expression recognition method based on the parallel convolutional neural network is proposed. Firstly, the face region is extracted from the pre-processed image by the face detector, in accordance with the detected feature points, the face image is cropped into three parts: eyes, noses and mouths. Then, Two CNNs were trained on the original and cropped data sets individually. Finally, the output of the two CNNs is gathered together to complete the classification of the expression. The modified AlexNet, VGGNet and ResNet were used to verify the method on the FER2013 data set. The recognition accuracy of the three models reached 66.672%, 69.407% and 70.744%, respectively. Experiments show that this method has a positive outcome on the recognition of expressions.

A reliable condition monitoring system can help improve the reliability of wind turbines and reduce cost. Condition monitoring method based on supervisory control and data acquisition (SCADA) data has been improved an effective method to achieve fault detection. With the development of machine learning technology, higher accuracy condition monitoring model can be established by using historic data. This paper proposes a novel condition monitoring method for wind turbines based on Long ShortTerm Memory (LSTM) algorithms. In terms of time series data, LSTM model can construct the correlation between the prior-known information and the current environment. The residual signals acquired by comparing the predicted data in a prediction model and the actual measurements from SCADA data can be used to achieve condition monitoring. The effectiveness of the proposed method is validated in the case study.

The primary objective of the present study was to avoid unnecessary prostate biopsy in biopsy-naive patients with Prostate Imaging Reporting and Data System, version 2 (PI-RADS v2), score 3, lesions.We reviewed our prospectively maintained database from January 2012 to July 2018. Logistic regression analyses were performed to test different clinical factors as predictors of clinically significant prostate cancer (CSPCa) and build nomograms. Calibration curves were used to assess the concordance between the predictive value and the true risk. Decision curves were created to measure the overall net benefit.The prostate cancer (PCa) and CSPCa detection rates were 37.2% (81 of 218) and 23.9% (52 of 218) in the PI-RADS v2, score 3, cohort. More PCa cases (61.7%; 50 of 81) and CSPCa cases (75%; 39 of 52) were found in the peripheral zone than in the transitional zone. Multivariate analysis showed that age, prostate-specific antigen density, lesion region, and apparent diffusion coefficient (ADC) were predictive factors for CSPCa and PCa. Internally validated calibration curves showed that the predicted risk of CSPCa was closer to the actual probability when the threshold was60%. Decision curves showed that a better net benefit was achieved when the model was used to guide clinical practice.More cases of PCa and CSPCa were seen in the peripheral zone than in the transitional zone among patients with PI-RADS v2, score 3. The positive predictive value for a positive ADC (900 μm

Ethnopharmacological relevance Intrahepatic cholestasis is a common condition of many liver diseases with few therapies. Yinchenzhufu decoction (YCZFD) is a representative traditional Chinese herbal formula used for treating jaundice and liver disease. Aim of the study To investigate the hepatoprotective effect of YCZFD against cholestatic liver injury and reveal its potential mechanism. Materials and methods Mice with alpha-naphthyl isothiocyanate (ANIT)-induced intrahepatic cholestasis were orally administered YCZFD at doses of 3, 6, and 12g crude drug/kg for 2 weeks followed by subsequent analyses. A serum metabolomics study was then performed to explore the different metabolites influenced by YCZFD using ultra-high-performance liquid chromatography coupled with linear ion trap-Orbitrap hybrid mass spectrometry (UPLC-LTQ-Orbitrap-MS/MS).The levels of individual bile acids in the serum, liver, and bile were determined by UPLC-MS/MS. The expression of metabolic enzymes, transporters, inflammatory factors, and cytokeratin-19 (CK-19) was determined by real-time PCR, western blotting, and immunohistochemistry. Results YCZFD administration decreased the serum biochemical indexes and ameliorated pathological damage, such as hepatic necrosis and inflammatory cell infiltration. Serum metabolomics revealed that the metabolites influenced by YCZFD were mainly associated with bile acid metabolism and inflammation. YCZFD administration effectively ameliorated the disordered bile acid homeostasis. The bile acid transporter, multidrug-resistance associated protein 2 (Mrp2), and the metabolic enzyme, cytochrome P450 2b10 (Cyp2b10), were upregulated in the YCZFD intervention group compared to those in the ANIT-induced group. YCZFD administration also significantly inhibited nuclear factor-κB (NF-κB) and its phosphorylation and decreased the expression of proinflammatory cytokines including tumor necrosis factor-α, interleukin-1β, and intercellular adhesion molecule-1 in ANIT-induced cholestatic mice. Additionally, the level of CK-19 was lower in the YCZFD intervention group than in the ANIT-induced cholestatic mice. Conclusion YCZFD administration ameliorated disordered bile acid homeostasis, inhibited NF-κB pathway-mediated inflammation, and protected the liver from bile duct injury. Therefore, YCZFD exerted a protective effect against cholestatic liver injury.

Background: The prevalence of sudden sensorineural hearing loss in children (CSSNHL) is consistently increasing. However, the pathology and prognosis of CSSNHL are still poorly understood. This retrospective study evaluated clinical characteristics and possible associated factors of CSSNHL. Methods: One hundred and thirty-six CSSNHL patients treated in Department of Otolaryngology-Head and Neck Surgery and Institute of Otolaryngology at Chinese PLA General Hospital between July 2008 and August 2015 were included in this study. These patients were analyzed for clinical characteristics, audiological characteristics, laboratory examinations, and prognostic factors. Results: Among the 136 patients (151 ears), 121 patients (121 ears, 80.1%) were diagnosed with unilaterally CSSNHL, and 15 patients (30 ears, 19.9%) with bilateral CSSNHL. The complete recovery rate of CSSNHL was 9.3%, and the overall recovery rate was 37.7%. We found that initial degree of hearing loss, onset of treatment, tinnitus, the ascending type audiogram, gender, side of hearing loss, the recorded auditory brainstem response (ABR), and distortion product otoacoustic emissions (DPOAEs) had prognostic significance. Age, ear fullness, and vertigo had no significant correlation with recovery. Furthermore, the relevant blood tests showed 30.8% of the children had abnormal white blood cell (WBC) counts, 22.1% had elevated homocysteine levels, 65.8% had high alkaline phosphatase (ALP), 33.8% had high IgE antibody levels, and 86.1% had positive cytomegalovirus (CMV) IgG antibodies. Conclusions: CSSNHL commonly occurs unilaterally and results in severe hearing loss. Initial severe hearing loss and bilateral hearing loss are negative prognostic factors for hearing recovery, while positive prognostic factors include tinnitus, gender, the ascending type audiogram, early treatment, identifiable ABR waves, and DPOAEs. Age, vertigo, and ear fullness are not correlated with the recovery. Some serologic indicators, including the level of WBC, platelet, homocysteine, ALP, positive CMV IgG antibody, fibrinogen, and some immunologic indicators, are closely related to CSSNHL.

The purpose of this work is to introduce and study a novel x-ray beam irradiation pattern for X-ray Luminescence Computed Tomography (XLCT), termed multiple intensity-weighted narrow-beam irradiation. The proposed XLCT imaging method is studied through simulations of x-ray and diffuse lights propagation. The emitted optical photons from X-ray excitable nanophosphors were collected by optical fiber bundles from the right-side surface of the phantom. The implementation of image reconstruction is based on the simulated measurements from 6 or 12 angular projections in terms of 3 or 5 x-ray beams scanning mode. The proposed XLCT imaging method is compared against the constant intensity weighted narrow-beam XLCT. From the reconstructed XLCT images, we found that the Dice similarity and quantitative ratio of targets have a certain degree of improvement. The results demonstrated that the proposed method can offer simultaneously high image quality and fast image acquisition.

TNF-α is a central proinflammatory cytokine contributing to malignant tumor progression in tumor microenvironment. In this study, we found the upregulation of miR-105 in colorectal cancer was associated with aggressive phenotype, and the enhanced expression of miR-105 was required for TNF-α-induced epithelial–mesenchymal transition (EMT). The expression of miR-105 was remarkably stimulated by TNF-α in a time-dependent manner using real-time qPCR analysis. Inhibition of miR-105 remarkably weakened the aggressive effects of TNF-α through preventing the activation of NF-κB signaling and the initiation of EMT. Furthermore, miR-105 was demonstrated directly targeted on the 3′-UTRs of RAP2C, a Rap2 subfamily of small GTP-binding protein. Consistently, suppression of RAP2C stimulated the role of miR-105, which dramatically promoted the invasion and metastasis of CRC cells. Thalidomide, a TNF-α and NF-κB inhibitor, significantly weakened the metastasis and homing capacity of miR-105-overexpressed CRC cells in nude mice. Our investigation initiatively illustrated the modulatory role of miR-105 in TNF-α-induced EMT and further CRC metastasis. We also offer a better understanding of TNFα-induced metastasis and suggest an effective therapeutic strategy against CRC metastasis.

In this study, a highly efficient fluorescent/phosphorescent white organic light-emitting device (WOLED) was fabricated using exciplex light emission. The hole-transport material 4,4ʹ,4ʺ-tris(N-carbazolyl)triphenylamine (TCTA), and electron-transport material, 4,7-diphenyl-1,10-phenanthroline (Bphen), were mixed to afford a blue-emitting exciplex. The WOLED was fabricated with a yellow phosphorescent dye, Ir(III) bis(4-phenylthieno [3,2-c] pyridinato-N,C 2 ʹ ) acetylacetonate (PO-01), combined with the exciplex. In this structure, the energy can be efficiently transferred from the blend layer to the yellow phosphorescent dye, thus improving the efficiency of the utilization of the triplet exciton. The maximum power efficiency of the WOLED reached a value 9.03 lm/W with an external quantum efficiency of 4.3%. The Commission Internationale de I'Eclairage (CIE) color coordinates ( x , y ) of the device were from (0.39, 0.45) to (0.27, 0.31), with a voltage range of 4–9 V.

In recent years, harvesting energy from broadband or low-frequency vibrations via piezoelectric effect has been realized due to worldwide research efforts, however harvesting energy from sway and multi-directional vibrations still present some challenges. To address this interesting issue, this paper reports a design and experimental verification of a beam-roller piezoelectric energy harvester that can scavenge energy from both sway and bi-directional vibrations. The beam-roller harvester is composed of a piezoelectric cantilever beam, a roller, and a frame. The beam and the roller are sensitive to two orthogonal directions of vibrations. The roller is also designed to sense the sway of the frame that acts as the guide rail of the roller. The energy captured by the roller is transferred to the beam via magnetic coupling, and the latter conducts the piezoelectric conversion. The frequency up-conversion is also achieved through this configuration which converts the low-frequency sway and vibration to the higher-frequency vibration of the beam. A lumped parameter model is used to predict the voltage output of the beam and simulate the excitation exerted to the beam by the roller. Experimental studies are performed as well to validate the theoretical predictions and examine the effects of different sway parameters on the performance of the beam-roller harvester. The obtained results indicate that employing a roller to actuate the piezoelectric cantilever beam to function is a feasible way to harvest energy from both the sway and the bi-directional vibrations.

The long term evolution (LTE) is a promising candidate solution for smart grid communication network due to its high data rate, lower latency, high mobility, and large coverage. In this paper, we discuss three resource scheduling algorithms for the LTE-based smart grids, including proportional fairness, round robin, and maximum rate scheduling schemes. In the simulations, we compare these three resource scheduling algorithms, the results show that the proportional fairness scheduler can achieve the best tradeoff between the average sum rate and the fairness among all the users.

Currently, the research of marine dual fuel engine is rare, while the combustion process of marine dual fuel engine is no precise conclusion. This paper built a combustion model of dual fuel engine by AVL FIRE software, and compared experimental data to prove the accuracy of the model, analyzed the characteristics in combustion process of marine dual fuel engines, provided a theoretical basis for the further optimize and design of marine dual fuel engine.

State assessment method of cables with extruded insulation and their accessories, DAC withstand test combined with a diagnostic test (such as PD measurement) has two shortcomings, the output voltage is not high enough for EHV cables, it cannot detect and locate PD effectively when defects are far away from signal acquisition point. This paper focus on DAC voltages up to 250kV and a kind of distributed measurement of PD. Defects existing in arbitrary of tested cable can be accurately measured in theory by installing sensor at intervals along the tested cable. This method has been validated on a long extra high voltage cross-linked polyethylene (XLPE) insulated underground cable circuit and the filed PD test has been completed successfully.

A controversy effect of perioperative statin use for preventing postoperative atrial fibrillation (POAF) and acute kidney injury (AKI) after cardiac surgery still remains. We thus performed current systematic review and meta-analysis to comprehensively evaluate effects of statin in cardiac surgery. 22 RCTs involving 5243 patients were included. Meta-analysis of 18 randomized controlled trials with 3995 participants suggested that perioperative statin use could decrease the risk of POAF (relative risk [RR] 0.69, 95%CI 0.56 to 0.86, P = 0.001), with a moderate heterogeneity (I2 = 65.7%, P H P = 0.884, I2 = 33.9%, P H = 0.157) or myocardial infarction (MI) (RR 0.84, 95%CI 0.58 to 1.23, P = 0.380, I2 = 0%, P H = 0.765), and even an increased trend of AKI was observed in patients with valve surgery. Perioperative statin use could decrease the inflammation response with no impact on clinical outcomes. In conclusion, perioperative statin use is useful in preventing POAF, particularly in patients with CABG, and ameliorate inflammation, while it has no effect on AKI and MI after cardiac surgery.

Harvesting energy from ambient vibrations via piezoelectric effect has been considered as a promising solution for implementing self-sustained low-power electronic devices. Most of the proposed piezoelectric energy harvesters (PEHs) are focused on the energy harvesting from uni-directional vibration. This is a strong limitation because the vibration may come from various directions in practical applications. To address this issue, this paper presents a design and experimental verification of a compact bi-directional nonlinear PEH that is sensitive to two orthogonal directions. This nonlinear PEH is composed of two magnetically coupled piezoelectric cantilever beams with orthogonal directions of deflection. Theoretical analysis and experiments reveal that the proposed PEH can not only harvest vibration energy from various directions but also provide an enhanced output voltage as compared to its linear counterpart. The introduction of magnetic coupling also enables the energy transfer between the two beams, which helps to restrain the excessive deflection of the two beams. Moreover, the advantage of nonlinear PEH is found to be highlighted at low-level excitation, whereas the resonant frequency of the nonlinear PEH drops as the excitation level reduces.

Based on the trip faults data of 10kV and 20kV distribution lines which come from actually power grid in China, this paper has done a large number of statistical analyses and investigations. Trip faults are classified and analyzed by fault positions, monthly changes, fault causes and so on. Preliminary analysis suggests that main factors which lead to trip faults are outer forces, meteorological conditions, improper operation and maintenance, quality of equipment and design processes. Rains, strong winds and lightnings have the worst impact on distribution lines in a period from June to August. External forces caused the most faults on conductors, towers and stay wires. According to different failure reasons, countermeasures are put forward pointedly,so can provide references for improving power supply reliability in distribution network.

The UHF method is one of the most important partial discharge (PD) detection means for GIS, while sensor technique is the key factor of the UHF method. In comparison with external sensors, built-in sensors can achieve higher sensitivity. In this paper, two parameters were quoted to evaluate the performance of the sensor, which are He and S11. He refers to the PD detection sensitivity of sensor; S11 refers to the impedance matching property of the sensor. The paper firstly designed a simulation model of sensor performance evaluation, and then studied the performance differences of four typically used or researched built-in UHF sensors (i.e., disc-type, dipole-type, spiral-type and logarithmic-type) by simulation tools of CST. The conclusions of the paper can provide a reference for performance evaluation and type selection of UHF built-in sensor. Keywords: Gas Insulated Switchgear (GIS), Partial Discharge (PD), UHF, Sensor, Sensitivity

This paper presents the basic principle of gas leak ultrasonic produce, the use of ultrasonic transducer array collecting leak ultrasonic signal, the signal filtering and power spectrum estimation of signal processing algorithms, intelligent gas leak detection system is developed. The detector is convenient to use, can realize quick check gas leak, application of virtual instrument for leakage signal analysis and processing, implementation of gas leak detection and estimation of leakage.

The industrial development has been aggravating the atmospheric pollution increasingly. The pollution flashover has always been one of the most important problems that bother the development of electric power system in China. The key to prevent the happening of pollution flashover accident is that the electric power operation department can timely and correctly master the condition of external insulation of insulator string in operation to take measures before the happening of pollution flashover accident so as to prevent the happening of pollution flashover accident. The thesis introduces a set of pollution flashover voltage evaluation system for porcelain insulator which can anticipate the pollution flashover voltage of insulator and prevent the happening of the pollution flashover accident through monitoring the weather conditions such as the temperature and humidity, electric parameters such as the leakage current and circuit operating conditions such as the voltage class and type of insulator and considering their influences comprehensively. According to the set of pollution flashover evaluation system, we had a mass of tests in the thesis to fully verify the accuracy and reliability of this system that satisfy the requirement of electric power department.

When one side jet engine of the twin jet engines in aircrafts fails, the aircrafts will sideslip relative to y-axis of aircrafts. The nose of the aircrafts will drop and the flight speed of the aircrafts will decrease. In order to maintain the balance of the aircrafts to ensure the safety of flight, the pilot has to carefully manipulate the aircrafts according to the actual situation and the control action. In this paper, dynamic characteristic of the aircrafts with twin jet engines under asymmetric thrust of aircrafts has been analyzed. Several manipulation methods of aircrafts with both the sideslip and bank were discussed to guarantee flight safety of aircrafts with asymmetric thrust. The control measurements to keep the balances of aircrafts were given to manipulate the aircrafts. In this situation, aircrafts will turn back as soon as possible and land at the nearest airport.

This paper reported a low-temperature thin film encapsulation (TFE) process based on atomic layer deposition Al2O3 layer for top-emission organic light-emitting devices (TE-OLEDs). The barrier characteristics of both H2O-based and O3-based Al2O3 films were investigated. O3-based Al2O3 TFE showed lower water vapor transmission rate (WVTR) of 8.7 × 10−6 g/m2 day and longer continuous operation lifetime of 5 folds compared to the device with H2O-based Al2O3 TFE under identical environmental and driving conditions. Furthermore, the extraction of emitting light of the devices with barrier layer was enhanced compared to the bared one. The theory simulation data were consistent with our experimental results and showed the potential for the design of TFE structures optimized for enhancing light transmission.

Mini tracked truck’s working unit is a device constrained by the dual parallelogram. This unit can make the goods remain translational during the process of loading and unloading so as to ensure the work process safe and reliable. Because the device is consisting of two parallelograms in series and using the rail to constrain its trajectory, the institutional force is very complicated. Therefore, this article uses statics method to analyze the force that acts on the working unit, establish the mechanical equations of the main arm cylinder and the lifting arm cylinder. The article respectively gives the simulation of the mechanical properties of the main arm cylinder during the loading process and the lifting arm cylinder during the lifting process basing on MATLAB. Research result provides a theoretical basis for the design of this type of working unit.

A high precision inspection method based on image mosaic was proposed for the final optics inspection in an Inertial Confinement Fusion(ICF).The image mosaic method contains image registration stage and image fusion stage.In the image registration stage,a registration method based on feature matching of local damaged area was used to overcome the exposure difference between the subimages and the lack of image information,and the moving information in the inspection system was used in image matching to improve the inspection precision and inspection efficiency.In the image fusion stage,the Poisson image fusion was adopted to eliminate the "stitching line" caused by an exposure difference and to implement the seamless mosaic.The images of final optics inspected by Final Optics Online Inspection(FOOI)was compared with the proposed method and Scale Invariant FeatureTransform(SIFT)method,and the results show that the proposed method is superior to SIFT method.The 4×4mosaic image shows that the inspection resolution of the FOOI device in the ICF has been improved significantly by proposed method.

In order to meet the crucial requirements of system miniaturization and low power consumption, a high performance digital signal processor for monopulse tracking radar application applying linear frequency modulation (LFM) signal is given. The system functions are partitioned into several time-division stages with software or hardware implementation methods, and then an optimized prototype system and the on-chip processing structure based on system on chip (SoC) concept are respectively proposed and implemented. In our case, the field programmable gate array (FPGA) chip is adopted to integrate all the processing algorithms invoked in the monopulse tracking radar. In the final verification section, the field experimental results fully prove the validity and engineering applicability of the digital signal processor.

Because of the seismic vulnerability of these masonry structures, many strengthened technologies for improving their its seismic performance of masonry panels have been improved in old days. In this paper, a rapid strengthening approach of masonry structures which is diagonal steel strips attached to the masonry panels is proposed. To investigate crack pattern, shear strength, lateral stiffness and ultimate displacement, four Specimens constructed at with 1:2 scale are designed. One specimen was not strengthened by steel strips, and the others strengthen by steel strips with different width and thickness. They are tested under combined constant vertical compression and cyclic lateral loading. The experimental results prove that reinforcement approach could a changed crack pattern. Also, it could significantly increase in the shear strength and lateral stiffness of masonry panels. The width of steel strips is more significant than the thickness of steel strips in strengthening shear strength and lateral stiffness of masonry wall.

We investigated Al2O3 atomic layer deposition growth layer for encapsulation of organic light emitting diodes (OLEDs). It was found that surface properties of these O3-based Al2O3 were superior to those of H2O based Al2O3 grown at relative higher temperatures. Therefore, the water vapor transmission rate of ∼60 nm thick Al2O3 films can be reduced from 4.9 × 10–4 g/(m2 day) (80 °C–H2O) to 8.7 × 10–6 g/(m2 day) (80 °C–O3) under a controlled environment of 20 °C and relative humidity of 60%. Besides, the OLEDs integrated with 80 °C–O3 based Al2O3 film were undamaged, and their luminance decay time was altered to a considerable extent.

In this paper, the mechanical automation system of automobile transmission test platform were designed, it has been used to test the performance of the transmission after the automobile transmission is assembled. The working condition of the analogue automobile is achieved by the mechanical automation test platform.

with high speed development of the digital image processing technology, and computer image processing technology used in scientific research more and more widely. Mineral, resources and environment, and other fields, image processing technology also has a wide range of applications. This paper is the application of digital image processing techniques to realize to study all the features of ore and automatically recognize ore , pattern recognition method applied to mineral recognition and testing field, so as to achieve the goal of mineral appraisal.

The input and output axis equipment is designed in the mechanical automation test platform. The input axis pull (positive pull) completes the noise test of the transmission at different gears. The output axis pull (reverse pull) test the shifting at different gears. The rotate speed adjustment of the input electromotor is done by transducer, and the rotate speed and torque design of the output electromotor is completed by the servo system. The mechanical automation electric control system of automobile transmission assembly test platform was designed. The working condition of the analogue automobile is achieved by means of the electric control systems control over the input electromotor and the output electromotors repeated power switch.

In the course of development, the ceramic art blends to science and technology culture, which forms a distinctive ceramic art and design performance practices. The literary and rhetorical device were applied to the design of ceramic art, making the ceramic works be full of personality, enhancing works infectious and conveys the mood of the effect. In this paper, it focuses on the design elements in the ceramic works, exploring the metaphor, a symbol, and narrative, exaggerated analogy rhetorical devices such as the use of ceramic art design, in order to create a suitable ceramic works.

To tackle the knowledge representation problem in developing intelligent conceptual design system, a BP network based approach is proposed, in which the related knowledge regarded various mechanical transmissions can be acquired and represented with the trained weight and threshold of neural network if they are turned into numerical data, encoded with binary strings, employed as learning samples, and fed into the constructed BP neural network. In a sense, the trained neural network can be used as a knowledge base of expert system to facilitate the choosing process of mechanical transmission. This paper provides a promising approach to deal with the automation of knowledge representation in conceptual design of mechanical transmission.

In our case, an original television (TV) broadcasting monitoring system is proposed and then implemented in order to meet the urgent requirements for rapid development of radio and television industry. The monitoring system involves four primary sub-modules, the functions of which are respectively described as image extraction, network transmission and storage, dispatching and configuration, data analysis, making a major contribution to safe broadcasting for TV stations. Besides, the monitoring system can be applied to various media platforms through system device or network promotion. In the final verification chapter, the loop-locked experimental results in both normal and emergency work modes demonstrate the validity and engineering practicability of designed TV broadcasting monitoring system.