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Due to the remarkable flexoelectric effect of nano structures, the electro-mechanical coupling of nano piezoelectric sensors has been studied. This paper studies polarization distribution and induced voltage (or output voltage) of the functionally graded piezoelectric cantilever nanobeam by the generalized variational principle and linear piezoelectric theory. The equilibrium equation and corresponding general boundary condition of functionally graded sensors are obtained. Based on the graded model, the analytic forms of the deformation and output voltage are given. The numerical result reveals gradient parameters and flexoelectric coefficient have the significant influence on the output voltage and electric polarization for the functionally graded sensor. The strong piezoelectric gradient in sensors would cause the significant effective flexoelectricity, which could generate the large output voltage at the large structural size.

Discrete robot manipulators have been a simple combination of several serially connected links and actuated joints. In addition, these manipulators have total degrees of freedom and prove to perform well in many fields. The motion of traditional robot is generated through the movement in discrete position, i.e., joints. A gradient neural network control is proposed for approximating the system uncertainty, such as the tracking of robot manipulators with model-free shown in this paper. Based on the method proposed above, the simulation results testify the validity and accuracy of our models.

In order to give full play to the advantages of UWB, we combine cruise robots with UWB technology to realize the function of indoor robot cruising. This paper proposes the Kalman filtering algorithm for optimizing the positioning fluctuation problem and several design schemes of cruise algorithms based on the PID algorithm, double tags method and electronic compass direction marking method.

Locally repairable code (LRC) in distributed storage system decreases repair degree of failed nodes. LRC with availability is extremely desired in distributed storage system because it permits local repair of failed nodes and parallel access of hot data. In this paper, a novel construction of LRCs with availability is proposed. Explicitly, by matrix iteration, two families of LRCs with all symbol locality and availability are constructed. The first family LRC is SA-LRC and keeps the code structure binary which is convenient to apply. The second family LRC is systematic code and possesses inspiring information rate $\frac{r}{{r + 2}}$. Our construction is concise and explicit parity-check matrices of LRCs are given.

The lungs are the primary organs of the respiratory system in humans. Meanwhile, lungs are also vulnerable and are easily damaged by inflammation or impact lesions during the course of our daily lives. Due to the epidemic of COVID-19 pneumonia, the confirmed and suspected cases often grow rapidly beyond the capabilities of medical institutions, rapid and accurate diagnosis for patients have become the first priority. Hence, ultrasound images have started to be adopted in lung diagnosis as they are more convenient, flexible, cheaper, and without ionizing radiation as compared with CT and CXR. This paper aims to use VGG, ResNet and EfficientNet networks to accurately classify Lung Ultrasound images of pneumonia according to different clinical stages based on self-made LUS datasets. The hyperparameters of the three networks were tuned and their performances were carefully compared. Our results indicate that the EfficientNet model outperformed the others, providing the best classification accuracies for 3 and 4 clinical stages of pneumonia are 94.62% and 91.18%, respectively. The best classification accuracy of 8 imagological features of pneumonia is 82.75%. This result is a proof of the promising potential of the LUS device to be used in pneumonia diagnosis and prove the viability of deep learning for LUS classification of pneumonia.

Fast development of distributed generation alters the electricity transactions and shift the interests of stakeholders in power industry. Transmission pricing for distributed generation transactions is one of many policy tools that can balance the interests among the grid companies, the electricity customers, and the distributed generation suppliers. This paper discusses the costs and benefits of distributed generation from the perspectives of stakeholders, proposes a process to quantify the costs and benefits of distributed generation from the perspective of grid companies in four business aspects: system demand, system operation, grid inspection and maintenance, and grid construction. An optimization model for transmission pricing of distributed generation transactions is proposed to minimize the interests shifting between the grid company and the end users. The proposed method is applied to an actual provincial region. The case study demonstrates that the proposed optimization model is applicable and justified.

The Medium Resolution Imaging Spectrometer (MERSI) onboard FY-3 satellite possesses the Characteristics of wide scanning range, short revisit period and high spectral resolution, which can provide wide-area and long-term sequence data for leaf area index (LAI) retrieval research. Long Short-Term Memory (LSTM) has great advantages of nonlinear fitting and can utilize the relationships between samples, can also solve the problem of large dimension of sample features. It is of great significance to apply it for LAI retrieval. Based on the FY-3B/ MERSI data simulated by hyperspectral data for five stages of maize canopy, this study explored multi-layer LSTM for LAI retrieval. Then, the results were compared with those of stepwise regression, partial least squares regression (PLSR) and single-layer LSTM method. The retrieval accuracies of Multi-layer LSTM model were better than those of other three models. Multi-layer LSTM provides a methodological reference for LAI retrieval studies.

Several discrete MOSFETs have to be connected in parallel to achieve a higher power application, because currently the commercially available GaN HEMT with highest current capability is only 60 A / 650 V. However, current sharing of paralleled GaN HEMT has been still considered as a big challenge issue. This paper presents current sharing analysis approach of paralleled GaN HEMT via feedback theory, which is a new physical insight. As converter designer, it is important that one try replacing some mathematical findings using physical insight. In this respect, a most valuable tool is feedback theory, which provide a feedback loop to help one to understand and learn the contribution of each key parameters such as on-resistance R DS (on) to current sharing of paralleled GaN HEMT. Therefore, several feedback loops about on-resistance R DS (on), gate threshold voltage (V GS (th)), trans-conductance (g m ), the feedback capacitor (C gd )and parasitic inductances have been developed to analysis the influence of paralleled GaN HEMT on current sharing.

With the increase of highway traffic flow, the number of toll lanes of highway toll stations increased. The number of vehicles arriving at the toll stations varies at different times. When the traffic is less, opening all toll lanes will cause unnecessary costs. In this article, based on a certain degree of customers' satisfaction, we use the simulation software to study the minimum number of toll lanes can be opened under different traffic conditions, and study the modes of opening toll lanes of toll station in order to save manpower and reduce costs.

Highway toll square traffic capacity has always been the focus of attention. In this article, in order to reduce the construction costs and increase traffic efficiency, a new design of highway toll square has been proposed. The land cover and use efficiency is used to calculate the construction costs. Then, we compare the data obtained by simulation software, such as the vehicle throughput, the vehicle delay time, the average speed and other indicators. We get the conclusion that the traffic capacity of the proposed model is better than traditional highway toll square.

With the battlefield environment becomes more complicated nowadays, it's difficult to achieve high precision target tracking only using single platform of target tracking system. Especially for maneuvering targets, the application of interactive multiple model (IMM) algorithm based on a variety model becomes necessary and feasible. At the same time, the best linear unbiased estimate (BLUE) filter is much more appropriate and useful than Kalman filter when it comes to deal with nonlinear system. Most of the time, we are blind to the correlation degree of our target during the merge process of tracking. We can track our target with multi-platform with introduction of Cross-Correlation (CI) fusion algorithm which is based on distributed data and proves its effectiveness by simulation.

Circuit aging induced by the negative bias temperature instability (NBTI) has become a major factor of reliability. The NBTI-induced aging of a logic gate can be mitigated by gate replacement technique only when the input gates of a logic gate are of some specific types. A protectability-aware gate replacement technique is proposed in this paper to mitigate NBTI-induced circuit aging. In the proposed technique the critical gates are identified by considering the impact of the types of input gates on their protectability, guaranteeing all the critical gates can be protected from static NBTI fatigue. Experimental results on ISCAS85 benchmark circuits under 45nm transistor model show that, compared with the techniques that neglect the impact of input gates' type, the proposed scheme has up to more than 4, 7 and 10 times, on average, improvement on NBTI-induced delay degradation under timing margin 5%, 10% and 15%.

Objective: To preliminarily investigate the correlation between coronary plaque type and acute coronary syndrome (ACS) using 320-slice volume computed tomography (CT). Methods: Fifty-seven patients who were suspected of having ACS and underwent CT within 30 days of onset were included in this retrospective analysis. All patients underwent 320-slice volume CT coronary image examination and were divided into four groups according to the coronary plaque components: Type I, fully calcified plaque; Type II, mixed plaque (calcification > 50%); Type III, mixed plaque (non-calcification > 50%); Type IV, non-calcified plaque. Results: Coronary plaques were found in 53/57 patients (93%). Of these, 16 (30.2%) had type I, nine (17.0%) had type II, 15 (28.3%) had type III and 13 (24.5%) had type IV plaques, respectively. The presence of Type II-IV non-calcified plaques was significantly associated with ACS (17/53, 32.1%, p 0.05). Conclusion: 320-slice volume CT coronary image can clearly depict the components of coronary plaque. Mixed plaques with non-calcified component > 50% are significantly associated with ACS.

Objective To explore the practicability and optimal dosage of polyaspartic acid (PASP)-surface-modified ultra-small superparamagnetic iron oxide (USPIO) (PASP-USPIO) in normal rabbit brain perfusion. Methods Thirty New Zealand rabbits were randomly divided into groups A1, A2, A3, A4 and C. Animals in groups A1–4 were intravenously injected (i.v.) with 5 μmol/kg, 10 μmol/kg, 20 μmol/kg and 40 μmol/kg PASP-USPIO, while animals in group C were injected (i.v.) with 0.2 mmol/kg gadolinium diethyl triamine-pentoacetic acid (Gd-DTPA), serving as a control group. Each group was subjected to T 2 ∗ Gradient Echo-Echo Planar Imaging (T 2 ∗GRE-EPI)-sequenced perfusion-weighted imaging to obtain signal intensity-time curves, which were used to calculate the regional cerebral blood volume (rCBV), the maximum signal drop percentage (SRR max ), and Q rCBV -Q SRRma X values. Data were compared within and between groups. Results The intra-group rCBV value and SRR max value were significantly different between gray matter and white matter. The inter-group Q rCBV and Q SRRmax values were also significantly different. ANOVA analysis indicated that the Q rCBV and Q SRRmax values in group A4 were significantly different from those in other groups, while there were no significant differences among group A1, A2, A3 and C. Conclusion PASP-USPIO has colloid stability and can be used in normal rabbit MR brain perfusion. The optimal dosage is 10 μmol/kg.

Based on saliency region representation of visual scene, a framework for quantifying the semantic similarity of two video scenes is proposed in this paper. Frame-segment key-frame strategy is used to concisely represent video content in temporal domain. Spatio-temporal conspicuity model for basic visual semantics, a neuromorphic model that simulates human visual system, is used to select dynamic and static spatial salient areas. With pattern classification technique, the basic visual semantics are recognized. Then, the similarity of two visual scenes is calculated according to information theoretic similarity principles and Tversky's set-theoretic similarity. Experiment results demonstrate the framework could compute quantitative semantic similarity of two video scenes.

In modern economic development, people will never doubt the tremendous effects of technology advances to the economic growth. However, as an important factor in promoting economic growth, technology is very different from natural resources, labor and capital. In this paper, the author carried on a quantitative calculation on the role of technology progress in China's economic growth for the past 20 years, using the Cobb-Douglas (C-D) production function and Solow model. The results show that the share of China's technology progress contributing to the economic growth is smaller than that of developed countries. Therefore, this paper suggests that the government establish an effective financial policy to support technology progress, and play a leading role in economic growth.

Frequent itemset mining is a critical step in association rule mining and plays an important role in many data mining tasks including strong rules, correlations and sequential rules. Diffset is an efficient frequent itemset mining algorithm which uses vertical database layout. An efficient hybrid algorithm DiffsetHybrid is brought out. The tests indicate that the new algorithm shows good performance with both sparse datasets and dense datasets.