Miracle-dz/UniFAR-FTUs huggingface dataset:
Power-Linked Predictive Control Strategy for Power Electronic Traction Transformer

Power electronic traction transformer (PETT) is a module-cascaded converter with high-frequency-link technology to realize high-power conversion. A typical structure of PETT contains a single-phase cascaded H-bridge rectifier in the first stage and several dual active full-bridge (DAB) dc–dc converters in the second stage. For PETT adopting such a complex topological structure, the control strategy also becomes complicated and should be carefully designed. In this article, a power-linked predictive control (PLPC) strategy for PETT is proposed based on the predictive controls of the H-bridge rectifier and DAB dc–dc converter. A power link is brought into the control strategy to connect the H-bridge rectifier with a dc–dc converter, through which the input power of PETT can match the output power. Moreover, the voltage balance control and power balance control are also combined with predictive control by the PLPC strategy. Using such a strategy, the fluctuation of the H-bridge rectifier dc voltage is suppressed, the circumfluence among modules is reduced, and the dynamic and steady-state performances are both improved compared with traditional strategy. Simulation and experimentation platforms with both resistance load and motor load are built to show the effectiveness and correctness of the PLPC strategy.
Improvement and Experience in Suture Methods for Rat Model of Focal Cerebral Ischemia

To establish a simple,stable and reliable model of focal cerebral ischemia.Methods Along with Zealonga method and modified method,the models of middle cerebral artery occlusion were created.Then after 24 h of operation,these two kinds of model were evaluated by four aspects: the neurological behavior,the cerebral infarction ratio,the relative standard deviation(RSD) of cerebral infarction ratio and the achievement ratio of model.Results All the survival rats demonstrated neurological deficit symptom after 24 h of operation.The cerebral infarction ratio between the two groups was not significant.The RSD of cerebral infarction ratio in the modified group was lower than that in the Zea-longa group while the success rate in the modified group were higher than that in the Zealonga group(χ2 = 4.37,P 0.05). Conclusion The modified method of focal cerebral ischemia model is easier to carry out and more reliable.And it is an ideal method for model of MCAO with higher success rate.
Nonlinear Analysis and Performance of Electret-Based Microcantilever Energy Harvesters

An energy harvester composed of a microcantilever beam with a tip mass and a fixed electrode covered with an electret layer is investigated when subject to an external harmonic base excitation. The tip mass and fixed electrode form a variable capacitor connected to a load resistance. A single-degree-of-freedom model, derived based on Newton’s and Kirshoff’s laws, shows that the tip mass displacement and charge in the variable capacitor are nonlinearly coupled. Analysis of the eigenvalue problem indicates the influence of the electret surface voltage and electrical load resistance on the harvester linear characteristics, namely the harvester coupled frequency and electromechanical damping. Then, the frequency–response curves are obtained numerically for a range of load resistance, electret voltage and base excitation amplitudes. A softening nonlinear effect is observed as a result of decreasing the load resistance and increasing the electret voltage. It is found that there is an optimal electret voltage with the highest harvested electrical power. Below this optimal value, the bandwidth is very small, whereas the bandwidth is large when the electret voltage is above this optimal value. In addition, it is noted that for a certain excitation frequency, the harvested power decreases or increases as a function of electrical load resistance when the coupled frequency is closer to short- or open-circuit frequency, respectively. However, when the coupled frequency is between the short-circuit and open-circuit frequencies, the harvested power has an optimal resistance with the highest power. Increasing the excitation amplitude to raise the harvested power could be accompanied with dynamic pull-in instability and/or softening behavior depending on the electrical load resistance and electret voltage. However, large softening behavior would prevent the pull-in instability, increase the level of the harvested power, and broaden the bandwidth. These observations give a deeper insight into the behavior of such energy harvesters and are of great importance to the designers of electrostatic energy harvesters.
Vascularization in tissue engineering: fundamentals and state-of-art

Vascularization is among the top challenges that impede the clinical application of engineered tissues. This challenge has spurred tremendous research endeavor, defined as vascular tissue engineering (VTE) in this article, to establish a pre-existing vascular network inside the tissue engineered graft prior to implantation. Ideally, the engineered vasculature can be integrated into the host vasculature via anastomosis to supply nutrient to all cells instantaneously after surgery. Moreover, sufficient vascularization is of great significance in regenerative medicine from many other perspectives. Due to the critical role of vascularization in successful tissue engineering, we aim to provide an up-to-date overview of the fundamentals and VTE strategies in this article, including angiogenic cells, biomaterial/bio-scaffold design and bio-fabrication approaches, along with the reported utility of vascularized tissue complex in regenerative medicine. We will also share our opinion on the future perspective of this field.
Improvement of moving least squares transformation in distance cartogram construction

Distance cartograms are deformed maps in which the distance of each of the preselected point pairs in the geographic map is changed in step with a specified value. They are constructed through two steps: locating the points included in the preselected pairs, and locating other points. A technique of moving least squares transformation is used in the second step. In this letter, the above technique is improved to maintain homeomorphism in the cartogram. The weight function used in the transformation is modified. Experimental results show the effectiveness of the proposed approach. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Load shifting of a supplier-based demand response of multi-class subscribers in smart grid

: We propose a demand response (DR) solution approach for a real-time pricing model with multi-class users to determine the electricity supply mix. The model aims to address the problem of power consumption overloading in peak hours using the real-time information obtained from the interaction between suppliers and users in a smart grid. The proposed DR algorithm allocates the overloaded demand assigned to a supplier to other electricity suppliers in order to satisfy all users’ demand while the supplier ensures to maximize the utility or reserved demand of users. Furthermore, a priority approach based on different user groups is developed for allocating the extra demand to other suppliers. Numerical experiments have been conducted to analyze the performance of the algorithm and compare the real-time electricity price with the fixed price.
Experimental Study of Sand Production during Depressurization Exploitation in Hydrate Silty-Clay Sediments

Silty-clay reservoirs are a weak point in sand production and sand control studies due to their low economy. However, China’s marine natural gas hydrates (NGH) mostly exist in silty-clay sediments, which restrict the sustainable and efficient development of NGH. In order to study the sand production of hydrate silty-clay sediments, hydrate production experiments in vertical wells and horizontal wells were carried out using a self-developed hydrate sand production and sand control simulation device. The results showed a great difference between the hydrate silty-clay sediments and hydrate sand sediments. The significant differences in production pressure and production temperature between the different layers indicated the low permeability and low heterogeneity of the hydrate silty-clay sediments. The sliding settlement of the overall depression in the horizontal well and overall subsidence in the vertical well of the hydrate silty-clay reservoir would easily lead to silty-clay flow and large-scale sand production. When water rates decreased, the property of “silty-clay sediment filtration and wall building” was found, which formed a “mud cake” around the wellbore. The good strength of adhesion and fracture permeability of the “mud cake” provided ideas for reservoir reformation. This study further discusses sand production and sediment reformation in hydrate silty-clay sediments.
Implementing digital technologies in one New Zealand school : challenges and opportunities

ii Acknowledgements . iii CHAPTER ONE: INTRODUCTION . 1 1.1 Background . 1 1.2 Context . 2 1.3 Research Aims and Questions . 4 1.4 Rationale . 5 1.5 Thesis Outline . 7 CHAPTER TWO: LITERATURE REVIEW . 9 2.
A Stator Flux Observer With Phase Self-Tuning for Direct Torque Control of Permanent Magnet Synchronous Motor

Owing to simple implementation and excellent performance, the conventional stator flux observer based on active flux concept is considered as a competitive scheme for direct torque control system of a permanent magnet synchronous motor. However, it is constructed by a large number of motor parameters, which may vary with the operating points. This leads to weak robustness. To improve its performance, a stator flux observer with phase self-tuning is proposed as an improved version in this article. First, relationship between the stator flux observed values obtained by current and voltage models and observed error of rotor position angle is analyzed. Then, according to the aforementioned analysis, a phase self-tuning link constructed by a proportional-integral regulator is proposed to ensure that the observed coordinate system converges to the actual one even under motor parameters vary conditions. Consequently, the robustness and accuracy of the stator flux observer can be improved. Finally, the stability of the proposed phase self-tuning link is analyzed. Experimental comparison between the conventional stator flux observer based on active flux concept and the proposed improved stator flux observer has been done, and the results verify the feasibility and effectiveness of the proposed stator flux observer.
Curriculum design and application of nursing safety management course

Objective To design a safety management course,in order to improve nurses' safety awareness and reduce medical disputes due to lack of safety awareness.Methods Based on the basic framework of nursing safety training in America and in reference of international literatures and expert consultation,a nursing safety management course was formulated and implemented.Results After training by the safety management course,nurses' safety awareness,reporting of adverse events and patient safety culture perception attitudes increased significantly(P0.05). Conclusion Systematic safety management curriculum and training can improve nurses' safety awareness.
Performance optimisation of a pharmaceutical production line by integrated simulation and data envelopment analysis

It seems that the use of mathematical models is not suitable for pharmaceutical production line optimisation and the use of simulation leads to better outputs and provides more flexibility than mathematical models. Therefore, in this study, a novel methodology based on the integration of simulation and data envelopment analysis is developed for performance optimisation of a pharmaceutical production line. For this purpose, first, an actual pharmaceutical production line was simulated, verified and validated. Afterwards, Data Envelopment Analysis (DEA) was developed for the scenario analysis. Finally, the weight of each indicator is identified through paired t-test. Results suggested that all the indicators are significant in the production unit. Optimisation model suggested that certain inputs and outputs had to be improved for the performance optimisation of the pharmaceutical unit. This is the first study in which an integrated simulation DEA is used for the performance optimisation of a pharmaceutical unit.
Study of Sweet Wormwood Compound on Pharmacodynamics of Preventing RA

Objective: To study the phannacological function of southernwood compound in treating rheumatoid arthritis ,RA. Methods: The effects of southernwood compound to feet swelling, granuloma, pain response and adjuvant arthritis were observed in rats. Results: The compound inhibited the feet swelling and granuloma distinctly (P 0.05, P 0.01), decreased the pain response induced by heat and chemical stumulation( P 0.05 , P0.01) and restrained the adjuvant arthritis distinctly(P 0.05, P0.01). Conclusion: Southernwood compound is effective for anti - inflammation, detumescence and removing pain.
Reconfigurable FET Biosensor for a Wide Detection Range and Electrostatically Tunable Sensing Response

The nanoscale field effect transistors have emerged as promising candidates for highly sensitive bio/chemical detection. Despite the massive progress, current FET biosensing technologies have limitations in terms of adaptability, versatility and throughput. Herein, we present an approach to dynamically tune the sensing performance of a FET biosensor by local electrostatic gating of the metal-semiconductor junctions. Depending upon the bias applied at the local gates, the device switches its operation configurations to deliver functionalities with markedly different sensing characteristics. Such reconfigurability at the runtime allows application suitability on the go, a feature non-existent in the state-of-art FET biosensors. The results of numerical simulations, based on framework validated against the experimental results, reveal promising sensing performance in terms of a high detection sensitivity (~105) with 104-fold tunable sensitivity window and a wide overall dynamic range spanning >4 orders of magnitude using a single device (a ~100-fold improvement over a conventional FET biosensor). The wide dynamic range is also established through a simple analytical approach based on 1:1 binding kinetics for antibody-antigen system. Taken together, the results strongly suggest that the proposed sensor design, representing the first approach of purely electrostatic phenomenon based tuning of sensing performance, has a considerable potential to enable the future development of more compact, multifunctional and adaptive biosensing platforms.
Potential Analysis of Hybrid Renewable Energy Systems for Self-Sufficient Residential Use in Germany and the Czech Republic

Independence from the power grid can be pursued by achieving total self-sufficient electricity supply. Such an energy supply model might be particularly interesting for settlements located in rural areas where enough space is available for energy generation installations. This article evaluates how and at what cost electricity demand of residential users across Germany and the Czech Republic could be covered by hybrid renewable energy generation systems consisting of photovoltaics, micro-generation wind turbines and batteries. High-resolution reanalysis data are used to calculate necessary system sizes over a large area by simultaneously accounting for the temporal variability of renewable energy. For every potential location in the research area, the hybrid system requirements for clusters of 50 self-sufficient single-family houses are calculated. The results indicate no general trend regarding the size of the respective technologies, although larger areas where PV-wind power complementarity enables lowering the total system costs and required storage capacities were determined. Assuming that the cluster of households could be constituted and depending on the location, the total installation and operation costs for the proposed systems for a lifetime of 20 years range between EUR 1.8 Million and EUR 5 Million without considering costs of financing. Regions with the lowest costs were identified mainly in the south of Germany.
Propagation Characteristics of Supercritical Carbon Dioxide Induced Fractures under True Tri-Axial Stresses

Supercritical carbon dioxide (SC-CO2) fracturing is a non-aqueous fracturing technology, which has attracted considerable attention on exploiting shale gas. In this study, shale specimens and artificial sandstone specimens were used to conduct SC-CO2 fracturing and water fracturing experiments to investigate the characteristics of SC-CO2 induced fractures. An acoustic emission (AE) monitoring device was employed to monitor the AE energy release rate during the experiment. The experiment results indicate that the breakdown pressure of SC-CO2 fracturing is lower than that of water fracturing under the same conditions, and the AE energy release rate of SC-CO2 fracturing is 1–2 orders of magnitude higher than that of water fracturing. In artificial sandstone, which is homogeneous, the main fracture mainly propagates along the directions perpendicular to the minimum principal stress, no matter if using SC-CO2 or water as the fracturing fluid, but in shale with weak structural planes, the propagation direction of the fracture is controlled by the combined effect of a weak structural plane and in-situ stress.
A Charge-Domain Switched-Gm-C Band-Pass Filter Using Interleaved Semi-Passive Charge-Sharing Technique

A highly reconfigurable charge-domain switched-<inline-formula> <tex-math notation="LaTeX">$g_{\mathrm {m}}$ </tex-math></inline-formula>-C biquad band-pass filter (BPF) topology that utilizes an interleaved semi-passive charge-sharing technique is proposed. It uses only switches, capacitors, linearity-enhanced <inline-formula> <tex-math notation="LaTeX">$g_{\mathrm {m}}$ </tex-math></inline-formula>-stages and digital circuitry for a 3-phase non-overlapping clock scheme. Flexible tunability in both center frequency and −3dB bandwidth is achieved with a scaling-compatible implementation. A 4<sup>th</sup>-order BPF prototype operating at a 1.2GS/s sampling rate is designed with a cascade of two reconfigurable biquad stages in a 65nm LPE CMOS process. A tunable center frequency of 35–70MHz is measured with programmable bandwidths and a maximum stop-band rejection of 72dB. The measured in-band IIP3 is +12.5dBm. The filter prototype consumes 7.5mW total power from a 1.2V supply voltage, and occupies an active area of 0.17mm<sup>2</sup>.
A Novel Deep Learning Approach for Machinery Prognostics Based on Time Windows

Remaining useful life (RUL) prediction is a challenging research task in prognostics and receives extensive attention from academia to industry. This paper proposes a novel deep convolutional neural network (CNN) for RUL prediction. Unlike health indicator-based methods which require the long-term tracking of sensor data from the initial stage, the proposed network aims to utilize data from consecutive time samples at any time interval for RUL prediction. Additionally, a new kernel module for prognostics is designed where the kernels are selected automatically, which can further enhance the feature extraction ability of the network. The effectiveness of the proposed network is validated using the C-MAPSS dataset for aircraft engines provided by NASA. Compared with the state-of-the-art results on the same dataset, the prediction results demonstrate the superiority of the proposed network.
The diagnostic value of 64-multislice CT in patients with peripheral arterial occlusive diseases:comparison with digital subtraction angiography

Objective To compare CT angiography with 64-slice CT and digital subtraction angiography(DSA) in the diagnostic accuracy and specificity of peripheral vascular diseases.Methods Thirty patients with peripheral vascular diseases were referred for selective digital subtraction angiography(DSA)and also undergone CT angiography.Findings were graded according to 5 categories:1,normal(0% stenosis);2,mild(1%-49% stenosis);3,moderate(50%-74% stenosis);4,severe(75%-99% stenosis);5,occluded.CT angiography findings were compared with those of DSA for every equivalent arterial segment;taking the outcomes of DSA as gold standard and analizing the sensitivity and specificity etc.Results In all 30 patients,720 vessel segments were evaluated with both imaging modalities.Comparing with DSA,the sensitivity of CTA to diagnose significant stenosis was 98.5% and specificity 99.2%;with positive predictive value(PPV) of 99.1% and negative predictive value(NPV) of 98.7%. Conclusion 64-slice spiral CT angiography is an accurate,safe,noninvasive technique for diagnosing peripheral vascular stenotic diseases.
WaterGrid-Sense: A LoRa-Based Sensor Node for Industrial IoT Applications

A Wireless sensor-network is used in the industry to monitor critical parameters. However, its industrial usage in harsh environments presents some challenges to the wireless communication signals such as noise, interference, etc. which contribute to poor quality of service. This paper presents analysis of WaterGrid-Sense, as a full-stack node based on LoRa deployed on a smart water management system. It has a smart interface platform and the ability to monitor and control in real-time. To determine its effectiveness for industrial usage, we conducted experiments to evaluate its power consumption rate and the reliability of the communication link while deployed in a harsh environment. The results obtained show that the sensor node can operate effectively with a battery for a long period of time until a cut-off voltage of 3.2 V. Moreover, despite the harsh environment, the received signals were sufficiently reliable. Thus, a WaterGrid-Sense could be deployed for industrial usage with great reliability and less maintenance costs.
Real-time object detection based on R-FCN network under structured scene of high-speed railway

In recent years, the object detection technology based on deep learning has made great breakthroughs, greatly improving the detection accuracy. However, most of the existing deep learning detection models are designed for multi-class object detection in natural scenes, which may lead to over-fitting when applied in structured specific railway scenes. Secondly, in order to meet the real-time detection requirements of high-speed comprehensive detection train with a speed of 350 km/h, the detection speed is put forward with extremely high requirements, and the existing deep learning model is difficult to meet the timeliness of high-speed detection. In this paper, we propose an optimized structured regions fully convolutional Networks (SR-FCN), which change the multiple small objects detection problem into single structured region location problem. The structured prior information of rail track is fused into the various processes of deep learning network including that sample construction, proposal region generation, network building and loss function constraint. By optimizing the regional proposal network as well as the anchor’s traversal number, the locating speed of the railway objects is greatly improved, and the locating error caused by local missing or background interference is avoided, which improves the robustness of detection. The experimental results show that the proposed SR-FCN network can not only achieve a high detection accuracy up to 99.99%, but also maintain a fast detection speed, which can meet the real-time detection at the high speed of 350 km/h.