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Additional file 3:. Note. The reason for using the ML tree from the 180s77Gaa dataset under a gene partitioning scheme as the reference tree.

Additional file 2: Fig. S1. The maximum likelihood tree estimated from the 77G180saa based on the gene partition models used as a reference to evaluate conflict and concordance among the 19 plastid datasets trees (Table 2). Pie charts depict conflict amongst the input trees, with the blue, green, red, and gray slices representing, respectively, the proportion of input bipartitions concordant, conflicting (supporting a single main alternative topology), conflicting (supporting various alternative topologies), and uninformative (BS < 80) at each node. The numbers below each branch are ICA values. Fig. S2. The maximum likelihood tree estimated from the SNP-ash dataset used as a reference to evaluate conflict and concordance among the six SNP gene trees (Table 2). Pie charts depict conflict amongst the input trees, with the blue, green, red, and gray slices representing, respectively, the proportion of input bipartitions concordant, conflicting (supporting a single main alternative topology), conflicting (supporting various alternative topologies), and uninformative (BS < 80) at each node. The numbers below each branch are ICA values. Fig. S3. The maximum likelihood tree estimated from the SNP-ash dataset used as a reference to evaluate conflict and concordance among the 41 gene trees using the dividing methods. Pie charts depict conflict amongst the input trees, with the blue, green, red, and gray slices representing, respectively, the proportion of input bipartitions concordant, conflicting (supporting a single main alternative topology), conflicting (supporting various alternative topologies), and uninformative (BS < 80) at each node. The numbers below each branch are ICA values. Fig. S4. The maximum likelihood tree estimated from the 77G180saa based on the gene partition models used as a reference to evaluate conflict and concordance among the 24 trees (plastid datasets and SNP datasets, Table 2). Pie charts depict conflict amongst the input trees, with the blue, green, red, and gray slices representing, respectively, the proportion of input bipartitions concordant, conflicting (supporting a single main alternative topology), conflicting (supporting various alternative topologies), and uninformative (BS < 80) at each node. The numbers below each branch are ICA values. Fig. S5. The divergence time of Oleaceae was estimated by BEAST according to age calibrations of four nodes based on the concatenated 76-coding gene dataset.

A measurement apparatus based on the optical fiber spectrometer is established to measure the directional spectral emissivity in the near infrared band. The sample is heated by a self-designed silicon carbide heater. The measurement angle can be adjusted from 0° to 82° by rotating the fiber collimating lens installed in a motorized rotary stage. The radiation signals of the sample and blackbody can be detected with a micro-optical fiber spectrometer in real time. The spectral emissivities of silicon wafer, silicon carbide, molybdenum, and tungsten are measured to verify the reproducibility and reliability of the apparatus. Furthermore, the directional spectral emissivity of high-purity chromium is investigated in the wavelength range from 950 nm to 1600 nm and the temperature range from 823 K to 1073 K. The influences of wavelength, temperature, and measurement angle on the spectral emissivity are analyzed in detail. It is found that the directional spectral emissivity of chromium decreases with the increasing wavelength and the temperature. The spectral emissivity of chromium rises slowly and then falls sharply with the increasing measurement angle. The combined uncertainty of emissivity measurement is evaluated, which is no more than 3 % for the wavelength and temperature range considered.

Additional file 5: Figure S4. Molecular phylogeny of Lagerstroemia resulting from ML (maximum likelihood) and BI (Bayesian inference) analyses using SSC regions (dataset-6). Maximum likelihood bootstrap values (BS) and posterior probabilities (PP) are shown at nodes. Branches with * indicate 100 % BS and a PP of 1.0.

Additional file 3: Figure S2. Molecular phylogeny of Lagerstroemia resulting from ML (maximum likelihood) and BI (Bayesian inference) analyses using LSC regions (dataset-4). Maximum likelihood bootstrap values (BS) and posterior probabilities (PP) are shown at nodes. Branches with * indicate 100 % BS and a PP of 1.0.

Additional file 4: Figure S3. Molecular phylogeny of Lagerstroemia resulting from ML (maximum likelihood) and BI (Bayesian inference) analyses using IR regions (dataset-5). Maximum likelihood bootstrap values (BS) and posterior probabilities (PP) are shown at nodes. Branches with * indicate 100 % BS and a PP of 1.0.

Additional file 2: Figure S1. ML tree for Lagerstroemia using combined three universal plant DNA barcodes and four highly variable regions.

In this study, the spectral emissivity of aeronautical alloy DD6 at eight temperatures (473 K, 523 K, 573 K, 623 K, 673 K, 723 K, 773 K and 823 K) over the spectral range from 3 μm to 20 μm is systematically studied under argon condition. The multi-temperature calibration method is adopted to accurately obtain the FTIR spectrometer response, and then the improved method that eliminates the disturbances caused by background radiation is used for spectral emissivity determination. The effects of temperature, wavelength and surface roughness on the spectral emissivity of DD6 are investigated. The results show that the spectral emissivity increases with increasing temperature and decreases with increasing wavelength, and the emissivity increases with increasing surface roughness. The fitting relationship between the spectral emissivity and temperature is established, and it is found that the fitting results of the complex model are more consistent than those of other models. To verify the validity of the complex model, the temperature inferred from the model is compared with that measured by the radiometer and thermocouple directly. The modified emissivity model based on the Agababov roughness function is established to infer the spectral emissivity of samples with different surface roughness. The relative combined uncertainty of spectral emissivity is evaluated to be better than 3.2% except for the atmospheric absorption bands.

A new directional polarized spectral emissivity measurement apparatus with the wavelength range of 4–20 μm was established to promote the development of thermal radiation transfer and polarization engineering. The measurement accuracy was improved by eliminating the background radiation with a high emissive thermostatic shutter and precisely determining the sample surface temperature. An accurate expression for directional polarized spectral emissivity was obtained taking into account the multiple reflection between the sample and the chamber. The linearity of spectral response was calibrated respectively in parallel and perpendicular polarized directions. The directional polarized spectral emissivity of a high-purity SiC sample was measured in a controlled environment to validate the capability of the apparatus. The excellent agreement between the measurement result and the literature data proved the reliability of the experiment apparatus and the measurement method. The measurement uncertainty was evaluated for each experiment, and the relative uncertainty was estimated to be less than 4.1%.

A new multi-angular polarized spectrum thermometry based on the optimal inversion wavelength selection method was proposed to accurately measure the surface temperature of optically smooth opaque surface. The surface temperature was inverted from the multi-angular polarized spectral radiance of sample by the least square method. The optimal inversion wavelength was iteratively determined by using the relation of λTS=2410 μm·K. The optimal inversion model was proved to be inverting the refractive index and the extinction coefficient by the ratio model P/S firstly and then calculating the surface temperature by the non-ratio model P+S. A proof-of-principle experiment with a high-purity SiC sample was carried out to validate the reliability of the inversion method. The result shows that the relative deviation of temperature is less than 1% at the optimal wavelength for the calculation performed by the optimal inversion model.

Multi-wavelength radiometric thermometry has a wide application prospect in many fields. However, due to unknown emissivity, the data processing algorithm remains a difficult problem. The Broyden–Fletcher–Goldfarb–Shanno (BFGS) algorithm is proposed to inverse true temperature and spectral emissivity without assuming the emissivity model. The BFGS algorithm can automatically identify the emissivity models of different trends. These simulation results show that given different initial emissivity has no significant influence on the inverse temperature and emissivity. Then, we select 0.5 as the initial emissivity and carry out the simulation experiments at 800 and 900 K, respectively. The maximum absolute error of temperature is less than 3.5 K and the computation time is less than 0.2 s. Thus, the algorithm has high precision and efficiency. Finally, the verification experiment indicates that the BFGS algorithm is effective and reliable. The proposed method can be applied to real-time temperature measurement in many industrial processes.

Finite element analysis model of magnetic flux leakage testing outside pipeline was established with analysis software in this paper. The leakage magnetic field characteristic curves of defects were obtained using this model. Also, the simulation on different diameter and depth of the cylindrical defects was carried out. And influence on flux leakage field, such as depth of defects corrosion defects was gotten. Then, detection device which can do inspection on pipeline with different diameters was manufactured based on the theory and finite element calculation results. The experiments with this device were carried out on the wall thickness of 8 mm and 6 mm pipeline with artificial defects above or under. And the results showed good agreement with simulation which meets engineering application of pipeline inspection.

In the highway traffic abnormal state detection, Support Vector Machine (SVM) algorithm is widely researched in recent years, but it still has some limitations. Aiming at the problem of improper selection of feature vector, the space and time characteristics of highway traffic abnormal state data is summarized, and the feature vectors of SVM are selected by Principal Component Analysis (PCA) properly. To solve the model parameters selection problem, the theory of Genetic algorithm (GA) is used to select SVM model parameters effectively. Also two-class SVM classification is extended to multi-class SVM classification which has a better command of the traffic running state on highway. According to the severity of the traffic incident, the traffic is divided into the state of no event, the state of mild congestion and severe congestion. The test software of SVM algorithm and the improved one are developed by using MATLAB and LIBSVM tool. The experimental result shows that the improved algorithm has a higher accuracy and a higher detection rate.

In this article, an experimental apparatus for measurements of the emissivity of a metal at different temperatures at \(1.5\, \upmu \text{ m }\) has been developed. Using this apparatus, the emissivity of steel 201, 304, and 321 samples has been measured at different temperatures, and the effects of the temperature, composition, and heating time of steel samples on the emissivity are analyzed according to the measured data. The measured data could be fitted to the same exponential function with the linear least-squares technique, and the fitting accuracy reaches relatively high quality. The measurement uncertainty of this experimental apparatus is analyzed. The analyses show that the measured emissivity is reliable.

A Ni 3 Al-Mo intermetallic compound alloy (IC6) was prepared by the multifunctional spray atomization and deposition plant. Tensile properties tests indicate that the spray deposited Ni 3 Al-Mo alloy possesses “ R ” characteristics in the yield strength, that is, the yield strength of the spray deposited IC6 increases with increasing of temperature and it reaches maximum at 760 °C. After that, it decreases with increasing of temperature. Analyses of dislocation structure by TEM reveal the relationship between the microstructure and yield strength. The results show that the change of the yield strength of the alloy with temperature is associated with the condition of dislocation winding, the pattern and quantity of the dislocation pairs and starting degree of the hexahedron slip system inside γ′ and γ phases. The TEM analysis of cracking by stereographic projection shows that with the increase of deformation stress the cracks form at grain boundaries and then quickly propagate, and some different slip bands exist in little planar zones; no matter at room temperature, middle temperature or high temperature, cracks craze along (111) plane octahedron slip.

Shrinkage defects can be formed easily at Critical location during low pressure die casting (LPDC) of aluminum alloy cylinder body. It has harmful effect on the products. Mold fi lling and solidifi cation process of a cylinder body was simulated by using of Z-CAST software. The casting method was improved based on the simulation results. In order to create effective feeding passage, the structure of casting was modifi ed by changing the location of strengthening ribs at the bottom, without causing any adverse effect on the part’s performance. Inserting copper billet at suitable location of the die is a valid way to create suitable solidifi cation sequence that is benefi cial to the feeding. Using these methods, the shrinkage defect was completely eliminated at the critical location.

This thesis involves the study about different processes including the tensile fracture, inter-layer tear or avulsion, as well as the interlaminar shear or split regarding carbon fiber composite materials with the aid of acoustic emission technique. Also, various acoustic emission signals that are released by composite samples in the process of fracture are analyzed. As is indicated by the test results, different acoustic emissive signals that are released by carbon fiber layers in various stages of damage and fracture bear different characteristics. Acoustic detection can effectively monitor the whole stage of elastic deformation, the damage development, and even the accumulation process while figuring out in an efficient manner about the internal activities of the composites, plus the diverse types of damages. In addition, its fabulous application value lies in its relevant structural evaluation as well as the evaluation of integrity with regard to carbon fiber composite.

Liquid ammonia storage leakage accident occurred frequently in recent years. In this paper, the Infrared thermal imaging Technology had been presented by introducing the applications of liquid ammonia storage inspection. It was indicated that the infrared thermal imaging technology had irreplaceable advantages in equipment insulation condition assessment, funneled detection, heat level judgment, electrical equipment failure hidden. The experiments showed that infrared thermal imaging technology could provide scientific references for early diagnosis and preventive maintenance of devices. And it had widely application prospect in the ammonia refrigeration system safety inspections.Copyright © 2014 by ASME

A new structure of multi-ring compound fiber optic rotation velocity measurement approach was researched, in this paper, based on the single ring Rayleigh backscattering type fiber optic rotation sensing principle. N fiber optic ring cavities and N 2×2 single-mode optical fiber coupler were used in this new structure to build a model for measuring changes of scattering. The output signal of optical rotation sensor detected by optical time domain reflectometer was deduced and analyzed in digitization by MATLAB software. And then the structure parameters of the multi-ring cavity lengths and coupling ratios were optimized according to the characteristic of output signal. When the system was constructed based on the optimization simulation results in the same condition that parameters setting were N=3, range of rotate speed measure 0∼0.18rad/s and measurement accuracy 0.01rad/s, the feasibility of the system was verified by measuring the Rayleigh backscattering signal in different speed. The use of compound multiple ring cavities, compared with single ring, improved the measuring signal strength, increased the effective test data, which is helpful to identify.

Mud pulse telemetry is a method used for measurement-while-drilling (MWD) in the oil industry. Information (tool-face orientation, temperature, pressure etc.) which is modulated by means of pulse positioning modulation (PPM) is sent from the bottom of the well to the surface by means of pressure waves in the drilling fluid (the drilling mud). Due to the influence of kinds of noise, the noise removal before decoding is of great importance. Considering the drilling fluid pulse's depending on the position and the width of the pulse to transmit the information, after the description of the mud pulse telemetry system and the analysis of the received signal, a new method based on the digital filter to process the signal received from the down-hole to recover the useful signal is applied. The result and the decoding process indicate that all of the pump noise, the reflection noise and other random noise can be wiped off, and the received signal can be recovered effectively and decoded with low error rate.

Swing scanning Earth sensor (SSES) is one of the key components in Middle Earth Orbit (MEO) satellites and High Earth Orbit (HEO) satellites for attitude sensing. Traditional calibration and test method could only be used in completely installed SSES. According to analysis of the calibration and test task in the uninstalled SSES, a new method and device which constitutes a closed-loop calibration test system in different development stage of SSES is proposed. The experiment and application results show that the method and device presented in this article constitute a better calibration test system for developing and producing the SSES.