Self-confocal NIR-II fluorescence microscopy for in vivo imaging

Benefiting from low scatter of NIR-II light in biological tissues and high spatial resolution of confocal microscopy, NIR-II fluorescence confocal microscopy has been developed recently and achieve deep imaging in vivo. However, independence of excitation point and detection point makes this system difficult to be adjusted. New, improved, self-confocal NIR-II fluorescence confocal systems are created in this work. Based on a shared pinhole for excitation light and fluorescence, the system is easy and controlled to be adjusted. The fiber-pinhole confocal system is constructed for cerebrovascular and hepatocellular NIR-II fluorescence intensity imaging. The air-pinhole confocal system is constructed for cerebrovascular NIR-II fluorescence intensity imaging, hepatic NIR-II fluorescence lifetime imaging, and hepatic multiphoton imaging.

An Inductive Active Filtering Method for Low-Voltage Distribution Networks

Three-phase unbalanced and nonlinear loads aggravate harmonic problems in low-voltage distribution networks. In this paper, a hybrid inductive and active filter (HIAF) system with a Ddy converter transformer is proposed. By establishing the circuit and corresponding mathematical models, the working mechanism of the HIAF system in harmonic suppression is analyzed. In the designed HIAF system, we install the detection point on the grid-side winding and the compensation point on the filtering winding. Since both windings have the same connection, no phase compensation between the harmonic detection point and compensation point is demanded. Eventually, we apply a harmonic damping control and zero-value impedance control strategy to realize harmonic suppression under both balanced and unbalanced loads. The simulation results show that the HIAF system can effectively suppress harmonics under various load conditions.

Development of a Low-Cost Data Acquisition System for Very Short-Term Photovoltaic Power Forecasting

The rising adoption of renewable energy sources means we must turn our eyes to limitations in traditional energy systems. Intermittency, if left unaddressed, may lead to several power-quality and energy-efficiency issues. The objective of this work is to develop a working tool to support photovoltaic energy forecast models for real-time operation applications. The current paradigm of intra-hour solar-power forecasting is to use image-based approaches to predict the state of cloud composition for short time horizons. Since the objective of intra-minute forecasting is to address high-frequency intermittency, data must provide information on and surrounding these events. For that purpose, acquisition by exception was chosen as the guiding principle. The system performs power measurements at 1 Hz frequency, and whenever it detects variations over a certain threshold, it saves the data 10 s before and 4 s after the detection point. A multilayer perceptron neural network was used to determine its relevance to the forecasting problem. With a thorough selection of attributes and network structures, the results show very low error with R2 greater than 0.93 for both input variables tested with a time horizon of 60 s. In conclusion, the data provided by the acquisition system yielded relevant information for forecasts up to 60 s ahead.

Research on Fault Location of Distribution Lines Based on the Standing Wave Principle

Aiming at the fast and accurate location of a single-phase ground fault in the distribution network, a single terminal injection signal location method, based on the standing wave principle, is proposed. Firstly, the double conductor standing wave principle formation, based on uniform transmission line theory, is analyzed, and the mathematical model of the fault distance algorithm is established. Secondly, a fault detection circuit is built by simulation, and the distribution trend of the standing wave and its relationship with unit capacitance and unit inductance are studied. By setting the source signal frequency and detection point interval and other parameters, the fault location of this method under direct grounding fault and through grounding resistance fault is simulated and studied. Finally, the fault distance is calculated and located by an experiment. The results show that the positioning accuracy is high, which verifies the effectiveness of the standing wave positioning method.

Heal nodes specification improvement using modified CHEF method for group based detection point network

Purpose The purpose of the paper is to make use of multiple parameters namely; residual energy, closeness to centre and mobility of detection point (DP) for the selection of detection point network (DPN). In the novel method proposed, the path will have less number of DPs participating in the entire DPN. Design/methodology/approach The proposed novel method will find out the special detection point (SDP) based on three criteria, namely, the amount of mobility for DP, the amount of remaining energy and the amount of distance between two DPs. This proposed method is an attempt to resolve the network lifetime problems during the communication of DPs over a period of time. It is developed for increasing the lifetime ratio, throughput, residual energy, number of alive nodes. Findings The simulation results of the novel method show the improvement over the existing methods investigated based on the lifetime ratio, throughput, remaining energy and alive nodes. Practical implications In the proposed method, the communication is done between different DPs in the network. The commutation is done using SDPs only from one cluster to another cluster. It is proposed for the implementation of energy efficient data sensing in mobile communication networks. Originality/value It is a significant mechanism for energy efficient data sensing of one DP to another DP of different clusters in the network. The total energy consumed for a period of time by the network is significantly reduced from the novel method.

Calculation Methods of Solution Chemical Potential and Application in Emulsion Microencapsulation

Several new biased sampling methods were summarized for solution chemical potential calculation methods in the field of emulsion microencapsulation. The principles, features, and calculation efficiencies of various biased Widom insertion sampling methods were introduced, including volume detection bias, simulation ensemble bias, and particle insertion bias. The proper matches between various types of solution in emulsion and biased Widom methods were suggested, following detailed analyses on the biased insertion techniques. The volume detection bias methods effectively improved the accuracy of the data and the calculation efficiency by inserting detection particles and were suggested to be used for the calculation of solvent chemical potential for the homogeneous aqueous phase of the emulsion. The chemical potential of water, argon, and fluorobenzene (a typical solvent of the oil phase in double emulsion) was calculated by a new, optimized volume detection bias proposed by this work. The recently developed Well-Tempered(WT)-Metadynamics method skillfully constructed low-density regions for particle insertion and dynamically adjusted the system configuration according to the potential energy around the detection point, and hence, could be used for the oil-polymer mixtures of microencapsulation emulsion. For the macromolecule solutes in the oil or aqueous phase of the emulsion, the particle insertion bias could be applied to greatly increase the success rate of Widom insertions. Readers were expected to choose appropriate biased Widom methods to carry out their calculations on chemical potential, fugacity, and solubility of solutions based on the system molecular properties, inspired by this paper.

Analysis of the skin wrinkling in out-of-plane joints of CFRP hat-shaped structure

Out-of-plane joints, between hat (omega) stiffeners and skin panels are asymmetric parts of the composite structure. Studies show that physical-mechanical conditions in these joints significantly affect skin forming quality. In the present article, aimed to investigate the mechanism of the skin wrinkle in the joints of carbon fiber reinforced plastics (CFRP) hat-shaped structure, the pressure testing apparatus based on the Pascal principle is used to surveillance the resin pressure dynamically in out-of-plane joints. In this regard, several influencing factors such as first-order holding time, forming pressure and relative volume of unidirectional fillers are studied. Obtained results show that increasing the first stage holding time can prolong the viscous flow state of the resin, and time to achieve pressure equalization at each detection point, thereby improving the dispersion of the pressure and reducing the possibility of wrinkles. It is found that as the forming pressure increases, the degree of skin wrinkles in the out-of-plane joints ameliorates. Moreover, for fillers with a relative volume within the range of 0–50%, the pressure transfer effect and the skin flatness is relatively dissatisfactory. It is concluded that the filler with a relative volume of 80–120% improves the skin wrinkle in out-of-plane joints.

Delamination Detection in Bimetallic Composite Using Laser Ultrasonic Bulk Waves

In this study, a method based on laser ultrasonic bulk waves is used to detect delamination in a bimetallic composite. For this purpose, several artificial delamination defects were created in a copper-aluminum sample using wire-electrode cutting. The research includes numerical simulation and experimental analysis. The propagation process of laser ultrasonic in Cu/Al bimetallic composite, the interaction between bulk waves and composite interface, and the effect of delamination defects on the ultrasound field were studied by numerical simulation. Suitable parameters and features were determined by numerical simulation, which provided a basis for the parameter selection of experimental research. The reflected shear waves from the composite interface can act as a sensitive feature to detect the delamination in Cu/Al bimetallic composites. The distance between the detection point and the excitation point was set to 2 mm to take into account the detection resolution and efficiency. The experimental results were in good agreement with the simulation results, and the C-scan image can intuitively show the location and size of delamination defects. The detection method based on laser ultrasonic bulk waves can effectively detect the delamination in Cu/Al bimetallic composite, which is suitable for the on-line detection of the rolling composite process.

Neurocognitive dynamics of near-threshold voice signal detection and affective voice evaluation

Communication and voice signal detection in noisy environments are universal tasks for many species. The fundamental problem of detecting voice signals in noise (VIN) is underinvestigated especially in its temporal dynamic properties. We investigated VIN as a dynamic signal-to-noise ratio (SNR) problem to determine the neurocognitive dynamics of subthreshold evidence accrual and near-threshold voice signal detection. Experiment 1 showed that dynamic VIN, including a varying SNR and subthreshold sensory evidence accrual, is superior to similar conditions with nondynamic SNRs or with acoustically matched sounds. Furthermore, voice signals with affective meaning have a detection advantage during VIN. Experiment 2 demonstrated that VIN is driven by an effective neural integration in an auditory cortical-limbic network at and beyond the near-threshold detection point, which is preceded by activity in subcortical auditory nuclei. This demonstrates the superior recognition advantage of communication signals in dynamic noise contexts, especially when carrying socio-affective meaning.

Evaluation of the Posterior Superior Alveolar Artery Prior to Sinus Floor Elevation via Lateral Window Technique: A Cone-Beam Computed Tomography Study

Aim: To evaluate the prevalence, diameter, localization of the posterior superior alveolar artery (PSAA) and the relationship between PSAA and the floor of the maxillary sinus and the thickness of the maxillary sinus lateral wall using cone-beam computed tomography (CBCT). Material and Methods: In this retrospective study, more than 500 CBCT images were retrieved. Out of them 156 CBCT images were related to the sinus floor elevation, among which 120 CBCT images were enrolled in the study based on the inclusion criteria, and 36 CBCT images were excluded. A total of 120 CBCT images of the PSSA from 60 patients comprising 32 (53.3%) men and 28 (46.7%) women were analyzed. Statistical data were analyzed using SPSS for Windows version 22. Descriptive statistics (mean, standard deviation, frequency) were used for the analyses. Results: The ages of the participants ranged between 26 and 76 years and the mean age was 54.48 ± 10.92 years. The PSAA was detected on the right side in 95% of the CBCT scans and on the left side in 85% of the maxillary sinuses. At the first detection point (FDP) and last detection point (LDP), the mean values of the distance between the inferior border of the PSAA and the floor of the maxillary sinus were 9.54 ± 4.27 mm and 7.91 ± 4.75 mm, respectively. The mean diameters of the PSAA at the FDP and LDP were 1.36 ± 0.46 mm and 1.12 ± 0.35 mm, respectively. Conclusion: Detection of the characteristics of the PSAA by using CBCT is crucial for handling the sinus floor elevation procedures uneventfully.