Simple Splicing Research Articles

Pressure and temperature sensors based on an over-discharged spliced polarization-maintaining photonic crystal fiber.

A polarization maintaining-photonic crystal fiber (PM-PCF) sensor for air pressure and temperature measurement is proposed by over-discharge splicing a section of PM-PCF to a single-mode fiber. This simple splicing procedure generates an air bubble in the PM-PCF at the splicing spot. The bubble and the PM-PCF cavities cascading sensor operates on three beams interference and demonstrates an envelope in the reflection spectrum. The pressure measurement results show that the resonance wavelength is linearly red shift with the gas pressure increasing, and the pressure sensitivity is nonlinearly increasing as the bubble length increases. A maximum sensitivity of the resonance wavelength shift is 4.05 nm/MPa in the range of 0.1 ∼ 0.9 MPa obtained with a sensor sample with 65µm bubble length. This sensor also shows 25.3 times more sensitivity amplification than the non-bubble PM-PCF sensor. Besides, the sensor also shows response to temperature, in the temperature range of 25 ∼ 500°C, the maximum sensitivity with 10pm/°C is obtained. Additionally, the proposed sensor also shows good repeatability and stability. In conclusion, the simple PM-PCF sensor can be applied in high-pressure and high-temperature monitoring in harsh environments.

DS-Former: A dual-stream encoding-based transformer for 3D medical image segmentation

Models that utilize self-attention mechanisms, including but not limited to Vision Transformers (ViTs), have shown promising performance in visual tasks like semantic segmentation. This is attributed to their capacity to capture global features of images, enabling them to learn more comprehensive representations. However, transformer-based models typically demand a considerable amount of training data to achieve satisfactory performance, while being deficient in the ability to efficiently extract local image features. As a result, these models may not be as effective in some computer vision tasks that involve small-scale datasets, like medical image segmentation. To address these issues, this paper proposes a dual-stream encoding-based transformer dubbed as Dual-stream Transformer (DS-Former). The dual-stream module in DS-Former can simultaneously acquire local and global features in the image and construct relation between the two kinds of features via self-attention. Compared with the simple splicing or serial connection, the dual-stream module can extract more comprehensive and hierarchical feature information from the fusion interaction of the two features. Our method is evaluated on the UK Biobank (UKBB) cardiac magnetic resonance imaging (CMR) dataset and The Beyond the Cranial Vault (BTCV) abdominal challenge dataset. The experimental results indicate that our DS-Former outperforms other state-of-the-art approaches on both datasets, indicating its potential for medical images semantic segmentation.

A Novel Multistage Back Projection Fast Imaging Algorithm for Terahertz Video Synthetic Aperture Radar

Terahertz video synthetic aperture radar (THz-ViSAR) has tremendous research and application value due to its high resolution and high frame rate imaging benefits. However, it requires more efficient imaging algorithms. Thus, a novel multistage back projection fast imaging algorithm for the THz-ViSAR system is proposed in this paper to enable continuous playback of images like video. The radar echo data of the entire aperture is first divided into multiple sub-apertures, as with the fast-factorized back projection algorithm (FFBP). However, there are two improvements in sub-aperture imaging. On the one hand, the back projection algorithm (BPA) is replaced by the polar format algorithm (PFA) to improve the sub-aperture imaging efficiency. The imaging process, on the other hand, uses the global Cartesian coordinate system rather than the local polar coordinate system, and the wavenumber domain data of the full aperture are obtained step by step through simple splicing and fusion, avoiding the amount of two-dimensional (2D) interpolation operations required for local polar coordinate system transformation in FFBP. Finally, 2D interpolation for full-resolution images is carried out to image the ground object targets in the same coordinate system due to the geometric distortion caused by linear phase error (LPE) and the mismatch of coordinate systems in different imaging frames. The simulation experiments of point targets and surface targets both verify the effectiveness and superiority of the proposed algorithm. Under the same conditions, the running time of the proposed algorithm is only about 6% of FFBP, while the imaging quality is guaranteed.

Multimodal Emotion Analysis Model based on Interactive Attention Mechanism

In traditional multi-modal sentiment analysis, feature fusion is usually achieved by simple splicing, and multi-modal sentiment analysis is only trained as a single task, without considering the contribution of inter-modal information interaction to sentiment analysis and the correlation and constraint relationship between multi-modal and single-modal (text, video and audio) tasks. Therefore, a multi-task model based on interactive attention mechanism is proposed in this paper, which uses inter-modal attention mechanism and single-modal self-attention mechanism to train multi-modal sentiment analysis and single-modal sentiment analysis together, so as to make full use of inter-modal and inter-task information sharing, mutual complement, and reduce noise to improve the overall recognition performance. Experiments show that the proposed model performs well on MOSI and MOSEI common data sets for multimodal sentiment analysis.

Dual determination of strain and temperature using cascaded fiber Fabry–Perot interferometers with wavelength and phase demodulation

A strain and temperature dual-parameter measurement device using cascaded optical fiber Fabry–Perot interferometers (FPIs) is reported in which both wavelength demodulation and phase demodulation are employed with the the parameters. A single-mode fiber (SMF), a short length of hollow-core fiber (HCF), a short section of SMF, and an HCF are spliced together to form the cascaded FPIs. In this structure, two dominant interference cavities are formed and two FPIs are generated, which are an air-cavity FPI and an air-silica cavity FPI. The sensitivities of the air-cavity FPI and the air-silica cavity FPI to strain or temperature are different, allowing the measurement of both parameters. In terms of wavelength demodulation, the temperature sensitivity of the air-cavity FPI (designated as FPI1) is 1.39 pm/°C and that of the air-silica cavity (designated as FPI2) is 8.56 pm/°C from 25 to 85 °C. In the strain range from 0 to 800 με, the strain sensitivity of FPI1 is 0.5 pm/με and that of FPI2 is 1.13 pm/με. Based on the sensitivity difference of the two FPIs, fixing the sensitivity matrix allows for simultaneous strain and temperature measurements. In addition, the dual parameters may also be measured by tracking the phase variations corresponding to the two FPIs. The reported sensor offers a simple splicing process, easy manufacture, low cost, and stable performance and provides a reference for dual-parameter dynamic measurements.

TERQA: Question answering over knowledge graph considering precise dependencies of temporal information on vectors

Time questions involve explicit and implicit constraints as well as complex time interval interactions, making them critical criteria for measuring the effect of knowledge base question answering. Although attention to temporal questions has spurred the development of temporal knowledge graphs, existing studies have focused on the simple splicing and fusion of temporal information with question or knowledge base embeddings, losing sight of the hidden interaction features between temporal information and embedded vectors. In this paper, we proposed TERQA, a temporal knowledge base question-answering approach to explore precise spatial dependencies between temporal information and embedded vectors. The exploration of the deep dependency between time and embedded vectors was divided into two stages. In the first stage, the Transformer model of depth extraction was employed to extract richer features from questions and the representation was enhanced with temporal information; in the second stage, high-level capsules were adopted to extract the low-level vector features for detailed pose determination, allowing a more precise deep dependency of temporal facts on embedded vectors. We conducted an experiment using two temporal question answering datasets, TempQuestions and CronQuestions, and the results showed that accuracy for TERQA improved 11.3% from baseline on the dataset TempQuestions with higher annotated information. Additionally, the adapted TERQA also showed varying degrees of improvements over the baseline in the larger but simply annotated dataset CronQuestions.

Strain and Temperature Discrimination Based on a Mach-Zehnder Interferometer With Cascaded Single Mode Fibers

An in-fiber Mach-Zehnder interferometer is proposed for the discrimination of strain and temperature. The sensor is based on two cascaded standard single mode fibers using three peanut tapers fabricated by simple splicing. The cascaded structure excites more frequency components, which induce four sets of interference dips in the transmission spectrum. One set of the spectrum dips have different sensitivities to temperature and strain from those of the other three. The sensor can discriminate strain and temperature by monitoring the wavelength shifts of two spectrum dips. Repeated experiments are taken both for strain and temperature increasing and decreasing scenarios. Experimental results show that Dip 1 has an average strain sensitivity of −0.911 pm/µε and an average temperature sensitivity of 49.98 pm/°C. The strain sensitivity for Dip 2 is negligible and its average temperature sensitivity is 60.52 pm/°C The strain and temperature resolutions are ±3.82 µε and ±0.33 °C.

A strain reflection-based fiber optic sensor using thin core and standard single-mode fibers

We propose and demonstrate a fiber optic strain sensor based on a simple splice between a thin core fiber and a piece of conventional single-mode fiber. Mode dispersion generates an interference reflection spectrum sensitive to strain and temperature. The sensor offers a competitive strain sensitivity of 2.4 pm/μɛ, good linearity (R2=0.9969), and a cursory repeatability analysis yielded variation. The thermal studies indicate minimal cross-sensitivity (2.9 μɛ/°C). The sensor offers a simple implementation without any intricate manufacturing.

Eurocode-compliant Topology optimisation and analysis of a steel Cover-plate in a splice moment connection

Advanced manufacturing has been supported in industries such as automotive, aerospace materials and medical devices, among others, by using Computer-aided Topology Optimisation (TO). However, civil engineering and, mainly, steel construction have been far from experiencing a similar revolution. This can be attributed to the lack of design methodologies, the difficulty in simultaneously optimising parts to non-conventional topologies while complying with design codes, and the advanced computational skill required. Motivated by these circumstances, this research synthetises Eurocode 3 design criteria for simple splice connections into geometrical constraints and optimises the topology of a landmark moment connection. To such an end, the Solid Isotropic Material with Penalisation (SIMP) method was used, and the Energy Stiffness Measure minimisation was established as the objective function. It has been found that both flanges cover-plates, as well as web cover-plates, could be optimised so that an overall reduction of 58% of the original weight was achieved, suggesting a remarkable potential for Topology Optimisation on structural steel connections while meeting the design standards requirements.

Bending behavior of splice connection for corner-supported steel modular buildings

Splice connection consisting of slip-critical high strength bolt and side plate is a promising connection type for future modular construction. However, recognitions on basic performance for this connection are still limited. To fill this gap, this paper conducted a comprehensive research on basic bending behavior of a simple splice connection proposed by the authors for corner-supported steel modular building. The basic bending behavior of the proposed splice connection was analyzed in details by combined experiments and numerical simulations. It is found that the proposed splice connection can achieve a favorable ductile behavior in bending. Bilinear profile with two stages is clearly observed in the relationship between moment and connection rotation. These two stages have different stiffness but the applied load can keep increasing in the second stage with excessive deformation of the specimen. Such phenomenon reveals adequate reserve of bending resistance for the proposed splice connection under large deformation scenario. Based on method of farthest point, a transition point is defined and determined in the relationship between moment and connection rotation. This transition point represents an important change in the bending behavior, which is valuable for practical design. Numerical simulations are also introduced to supplement the tests. The analyses on stress states of components and variation in bolt pre-tension force properly explains anisotropy in resistance at the transition point for different loading directions. A parametric study is further conducted. Results indicate that the proposed splice connection possesses satisfactory tolerance for loss of bolt pre-tension force in the practical construction.

Nanoindentation mechanical properties of CoCrFeNi high entropy alloy films

ABSTRACT CoCrFeNi high-entropy alloy films were deposited under different substrate bias by magnetron sputtering using a simple splicing target. The hardness, elastic modulus and creep properties of the films were measured by nanoindentation. The results showed that with the increase in substrate bias, CoCrFeNi films were always mainly composed of FCC phase and demonstrated smooth and dense surface with uniform distribution of elements, but the preferred orientation of the films changed from FCC (200) to no preferred and then to FCC (111). The hardness and elastic modulus of CoCrFeNi films were not sensitive to the strain rate of nanoindentation (0.05–0.15 s−1). The maximum hardness of the film was about 10.4 GPa under the substrate bias of –50 V, while the maximum elastic modulus of 249.8 GPa appeared under the substrate bias of –200 V. The applied negative substrate bias (−50 V ~ –200 V) could improve the elastic modulus and creep properties of the films.

An analytical model for the loading capacity of splice-retrofitted slender timber columns

Retrofitting timber columns in traditional timber structures with a steel jacketed splice joint has advantages of aesthetic appearance and similar mechanic performance to the intact columns as compared to conventional simple splice columns. The axial compression behavior of such retrofitted splice columns has been studied experimentally in detail. However, there is still a lack of a calculation model for their axial compressive strength and general guideline for their design. The objective of this study is to establish a theoretical calculation model for this type of retrofitted splice columns. Firstly, a theoretical model for the axial compressive strength of splice columns retrofitted with a steel jacket is proposed considering the contact stresses at a splice joint and the relevant stability theory. Secondly, the buckling modes of splice columns and the actual stress distributions at the splice joints (i.e. the compressive stresses at the steel-timber and timber-timber interfaces) are thoroughly investigated. Finally, the theoretical model is validated by the experimental data and finite element analysis results with different splice parameters. Comparisons show that the theoretical calculations in terms of the bearing capacity and stability coefficient agree well with the experimental results. The proposed theoretical model is also shown to be suitable for predicting the axial compressive strength of a retrofitted splice column with the location of the splice from the column end ranging from 1/5 to 1/2 of the column length. The relative errors in the theoretical bearing capacities with respect to the finite element results are found to be less than that using the stability coefficient. From the analysis results, the length of the splice and the total length of the steel jacket are recommended to be in the range of 0.5~1.5 and 2~4.5 times of the column diameter, respectively. This proposed theoretical model can be applied in the retrofitting design of timber columns in historical timber structures, and it can also be applied in the development of new large-space timber structures where splice columns may be incorporated.

A method of controlling adaptive optical system combined with image restoration technology

In the field of astronomical high resolution imaging, adaptive optical correction and image restoration are necessary, and these two techniques can be used either separately or jointly to improve the quality of observed images. However, for a long time, adaptive optics and image restoration technology have been developing independently because they belong to different research fields, and even though they are combined together, it is just a simple splicing of the two technologies, with no crossover between the two. Such a control method results in adaptive optical correction producing only the best possible intermediate result—optical imaging, but is out of control for the final result—restored image. Therefore, it is of great significance to study a control method that combines the two methods in order to obtain the high-quality restored image. In this paper, the traditional hybrid method (adaptive optics + image post-deconvolution) is analyzed and its defects are expounded. The idea of combining adaptive optics and image restoration for system analysis is proposed for the first time, and the concept of correction degree of deformable mirror (the scaling ratio of control voltage of deformable mirror to that of traditional control voltage) is proposed. By changing the degree of correction, the correction residual of the deformation mirror and the detection error of the wavefront sensor can be adjusted. It is proved that there exists an optimal value of the quality of the reconstructed image in the direction of reducing correction degree, and a new control method is obtained by using the optimal correction degree to correct the control voltage of the deformation mirror. For the application in point target imaging, the simulations are carried out with 37-element and 61-element deformable mirrors under several typical wavefront aberrations, and the results show that this method can obtain a better restoration image than traditional methods. This method has more potential applications in adaptive optical systems with large fitting residuals. The idea that adaptive optics and image restoration are considered as a whole, has not been reported in the literature before, so the work of this paper provides a new way of thinking for the research in related fields.

Experimental Demonstration of Temperature Sensing with Packaged Glass Bottle Microresonators.

Whispering gallery mode (WGM) glass bottle microresonators are potential highly sensitive structures for a variety of physical and bio-chemical sensing applications. In this paper, we experimentally demonstrate the practical use of glass bottle resonators as temperature sensors. The basic parameters, such as WGM resonance wavelengths, free spectral ranges, and Q factors, have been investigated by coupling light from a tapered fiber to the bottle structure. We show the spectral characteristics of the WGMs by choosing different bottle dimensions and taper diameters. For practical measurements, a robust 3D-printed package that includes the bottle resonator and the tapered fiber has been proposed. The packaged bottle has a central diameter Dc = 207 µm and a length L = 300 µm. Temperature sensing experiments were also performed. A linear response of the WGM shifts as a function of the temperature is confirmed. The fitted experimental data indicate a temperature sensitivity of 10.5 pm/K at λ ~ 1550 nm, resulting in a limit of detection of 0.06 K. These values can be compared with values reported for other WGM resonators. Additionally, bottle resonators are made with simple splicing methods and their assembly method can be easily defined due to large coupling tolerances.

Practical splicing of poly-methyl-methacrylate plastic optical fibers.

This Engineering and Laboratory Note describes a simple, fast, cost-effective, and practical splicing technique for poly-methyl-methacrylate (PMMA) plastic optical fibers. We believe this technique can be useful for home networks, laboratory research, and educational uses. It employs a widely available, low-cost transparent adhesive combined with a suitable alignment sleeve. The fiber tips did not need to be cleaned or polished, and the polyethylene jacket did not need to be removed. The alignment between the cleaved fibers was performed by means of the jacket. Low insertion losses were measured for the main PMMA-based fiber types.

Strain measurement at high temperature environment based on Fabry-Perot interferometer cascaded fiber regeneration grating

In this paper, a Fabry-Perot interferometer structure (FPIS) cascaded with a regenerated grating (RG) is proposed for strain measurement in a high temperature environment. The FPIS is fabricated by splicing a section of simplified hollow-core fiber (HCF) between two single-mode fibers (SMFs). Simple splicing and cleaving techniques are used to optimize the interferometer in order to produce the FPIS with the properties of lower temperature sensitivity and high strain sensitivity. The optimized FPIS is cascaded with a seed grating and then subjected to a thermal annealing process in order to activate the RG. Experimental results indicate that the proposed sensor can be used for simultaneous measurement of strain and temperature over ranges of 0μe to 600με and 19°C to 600°C, respectively, and consists of a matrix with a low condition number of 12.09.

Nano-displacement sensor based on photonic crystal fiber modal interferometer.

A stable nano-displacement sensor based on large mode area photonic crystal fiber (PCF) modal interferometer is presented. The compact setup requires simple splicing of a small piece of PCF with a single mode fiber (SMF). The excitation and recombination of modes is carried out in a single splice. The use of a reflecting target creates an extra cavity that discretizes the interference pattern of the mode interferometer, boosting the displacement resolution to nanometer level. The proposed modal interferometric based displacement sensor is highly stable and shows sensitivity of 32 pm/nm.

Detection of recurrent alternative splicing switches in tumor samples reveals novel signatures of cancer.

The determination of the alternative splicing isoforms expressed in cancer is fundamental for the development of tumor-specific molecular targets for prognosis and therapy, but it is hindered by the heterogeneity of tumors and the variability across patients. We developed a new computational method, robust to biological and technical variability, which identifies significant transcript isoform changes across multiple samples. We applied this method to more than 4000 samples from the The Cancer Genome Atlas project to obtain novel splicing signatures that are predictive for nine different cancer types, and find a specific signature for basal-like breast tumors involving the tumor-driver CTNND1. Additionally, our method identifies 244 isoform switches, for which the change occurs in the most abundant transcript. Some of these switches occur in known tumor drivers, including PPARG, CCND3, RALGDS, MITF, PRDM1, ABI1 and MYH11, for which the switch implies a change in the protein product. Moreover, some of the switches cannot be described with simple splicing events. Surprisingly, isoform switches are independent of somatic mutations, except for the tumor-suppressor FBLN2 and the oncogene MYH11. Our method reveals novel signatures of cancer in terms of transcript isoforms specifically expressed in tumors, providing novel potential molecular targets for prognosis and therapy. Data and software are available at: http://dx.doi.org/10.6084/m9.figshare.1061917 and https://bitbucket.org/regulatorygenomicsupf/iso-ktsp.

A New Relation of Second Order Limit Language in Simple and Semi-Simple Splicing System

Splicing system, which is an abstraction of operations on DNA molecules, can be modelled mathematically under the framework of formal language theory and informational macromolecules. The recombinant behavior of the set of double-stranded DNA molecules under the influence of restriction enzyme and ligase further lead to the cut and paste phenomenon in splicing system. The theoretical study of splicing language has contributed to a new type of splicing language known as a second order limit language, which is an extension of limit language. Some types of splicing system can produce second order limit language. Y-G splicing system is chosen among other models to model the DNA splicing process as this model preserves the biological traits and presents the transparent behavior of the DNA splicing process. In this paper, the relation between second order limit language with simple splicing and semi-simple splicing system are presented.

Recognition of Simple Splicing Systems using SHAutomaton

Splicing language is the language which results from a splicing system. Splicing system was first introduced by Tom Head in 1987 as the mathematical model of systems of restriction enzymes acting on initial DNA molecules. Splicing languages are closely related to automata theory. Simple splicing systems can be recognized by SH-automata diagrams due to the regularity of splicing languages. SH-automaton defines exactly one language which is the language generated by the simple splicing system. In this paper, the concept of firm and maximal firm subwords are introduced. Some examples are then given to illustrate the maximal firm subwords of a word in a simple splicing system. Taking the SH-automata concept, which is a short compact way of encoding normal non-deterministicautomata in the special case of SH systems, the maximal firm subwords of the initial words of an SH systems serve as the labels for the associated SH-automaton. Some examples which will show the maximal firm subwords of the words in the initial set I, the regular expression for the language generated by the given splicing system and the simplest non-deterministic automaton that recognizes the corresponding splicing system are also given