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In this paper, a fiber optic sensor was designed and implemented to detect the change in refractive index of sodium chloride salt solution based on the local surface plasmon resonance (LSPR) phenomenon. This sensor was manufactured using a plastic optical fiber (POF), this optical fiber was bent in a U-shape with 0.5cm bending diameter, and then the cladding and part from core of the fiber were removed by polishing at the sensor head to become as a D-shape in cross section. The sensor was coated with 30 nm thickness of gold nano particles (GNPs) by DC plasms coating technology and it was tested with sodium chloride solution, the detection sensitivity was 466.66 nm/RIU. To enhancement the sensitivity, the latest sensor was coated with 20nm thickness of graphene nano material and retested with same samples of sodium chloride solutions. It was found that graphene improved the sensitivity by an excellent amount, where shift in wavelength was 20nm and highest sensitivity obtained was 666.666 nm/RIU.

Fourier transform profilometry (FTP) is widely used for real-time three-dimensional (3-D) surface shape measurement with a single frame of projection fringe pattern. The band-pass filter is very im...

A highly sensitive refractive index (RI) sensor based on the surface plasmon resonance (SPR) phenomenon is proposed and demonstrated. The sensor is composed of a quasi D-shape ten-fold photonic qua...

The article focuses on a numerical analysis of the projected use of the T-15MD tokamak machine after its physical launch for generating a configuration with negative triangularity of the plasma filament cross section (an inverted D shape) on the installed magnetic field coils. The study is of interest in connection with recent experiments on several tokamaks that have demonstrated a distinct improvement achieved with such operating regimes compared with standard plasma containment configurations.

Stress is a normal physiological and behavioral response to a stimulus that somehow disturbs the maintenance of homeostasis, leading to changes in cortisol levels. When stress is persistent and uncontrolled, it can severely affect several areas, such as human health and some marine biology sectors, including aquaculture production. Currently, the detection of cortisol is performed in laboratories using conventional techniques with several disadvantages, one of them being the long waiting time for a response. Therefore, it is essential the development of miniaturized analytical devices capable of monitoring in real-time, detecting and quantifying cortisol in point of care (POC). Special optical fiber structure, in this case, D-shape in silica optical fibers (SOF) and polymeric optical fibers (POF) coated with gold (Au) were used in this work for the development of immunosensors based on surface plasmon resonance (SPR) for cortisol (stress hormone) detection. In the laboratory, Au coated SOF (Au-SOF) and Au coated POF (Au-POF) were initially characterized at refractive index (RI) with eight glucose concentrations ranging from 1.333 to 1.386 RI units (RIU). The obtained sensitivities were, respectively, 1646.67 ± 91.66 nm/RIU, being lower than the simulated one with 2138.95 ± 142.65 nm/RIU, and 1566.81 ± 96.87 nm/RIU. Subsequently, the fibers were functionalized with anti-cortisol antibodies using cysteamine as the intermediate linker to allow the immobilization of the antibodies to the Au surface. After this procedure, both immunosensors were tested for cortisol concentrations ranging from 0.1 to 100 ng/ml to compare the performances, in which the Au-SOF and Au-POF immunosensors presented a total resonance wavelength shift of 3.22 and 2.10 nm, and sensitivities of 1.08 ± 0.21 nm/log(ng/mL) and 0.52 ± 0.03 nm/log(ng/mL), respectively. Different limits of detection (LODs) were calculated using different methods for each type of immunosensor. One method consisted in performing a Hill fitting to the results and another considering the response of the control interferents. For Au-SOF and Au-POF, the LODs attained through the first method were 0.12 and 0.13 ng/mL (considering the resonance wavelength shift), respectively, and 0.14 ng/mL considering the intensity variation of Au-POF. The second method enabled a LOD of 1.75 and 1.97 ng/mL for Au-SOF and Au-POF, respectively.

Different plasma materials have a great influence on the sensing performance of the surface plasmon resonance temperature sensor based on photonic crystal fiber (PCF-SPR). According to existing research, titanium dioxide is an excellent auxiliary plasma material. In this paper, a high-sensitivity D-shape PCF-SPR temperature sensor has been proposed based on finite element method simulations. The PCF-SPR temperature sensor based on Au–TiO2 and Ag–TiO2 plasma materials was numerically analyzed. The sensor was optimized by adjusting the thickness of the metal layer and pore radius. On the surface of the results, the proposed PCF-SPR temperature sensor has a higher sensitivity when coated out of Au–TiO2, and a better linear relationship when coated out of Ag–TiO2. The temperature sensor works mainly in the infrared band, and the maximum sensitivity is 4.5 nm/°C, 4.0 nm/°C in the detection temperature range of − 15–35 °C. The sensor has the advantages of miniaturization, high integration, and high sensitivity, and can be used in biomedicine chemical detection and agriculture, and other fields. At the same time, the feasibility of the square air hole is verified at the simulation level, which is of great significance to the development of photonic crystal fiber.

A D-shape elliptical stoma photonic crystal fiber (PCF) based on surface plasmon resonance is proposed and investigated with finite element method. The gold film is deposited on the D-shaped surface, avoiding metal and analyte filling into air holes. Moreover, SPR effect has strong local field enhancement effect, which improves the sensing and filtering performance. The birefringence of PCF is improved by designing elliptical air holes. The transmission mode field and coupling phenomenon are analyzed. The results show that the SPR PCF can realize both communication window filtering and refractive index sensing. At 1.48 μm, the loss of y- polarization is 784 dB/cm, while that of x-polarization is only 0.43 dB/cm. The refractive index sensing sensitivity can reach 4494 nm/RIU as the detection range is from 1.345 to 1.375. The highest sensitivity is 9508 nm/RIU as the detection range is from 1.42 to 1.44. Our proposed PCF has excellent sensing and filtering, and has a good application prospect.

The phase coding plus sinusoidal fringe method involves embedding the codeword into the phase domain, and is suitable for different contrast variation surfaces. However, as the number of phase codi...

In this paper, the forming mechanism of the 2-D shape and position error for turning workpiece was discussed and an on-line detecting and analyzing method was designed. Firstly, two laser displacement sensors were orthogonally distributed on both sides of the workpiece to obtain the distance data from each measuring point of the rotating workpiece to the sensor. Then, according to the geometric position relationship, the synchronous error, asynchronous error and surface roughness were solved by the method of stepwise error separation, and the inverse calculation was carried out. The simulation results under different parameters were analyzed. The results show that the shape and position error obtained by the simulation method are consistent with the verification results of inverse calculation. The results of this method are relatively stable. Therefore, the simulation analysis method has good practicability and maneuverability. Finally, the feasibility and correctness of the algorithm were verified by experiments.

In this paper, we propose a method to realize real-time three-dimensional (3-D) measurement with a radial spatial carrier phase shifting algorithm. The circular fringe patterns are continuously projected onto the moving object; the distorted fringe patterns are recorded by CCD. In the 3-D reconstruction process, three patterns consisting of one recorded image and two artificial phase shifting fringe patterns are used to implement phase shifting, where the two artificial patterns are formed by numerically shifting the recorded image along the radial direction. Compared with traditional carrier phase shifting method, the proposed method possesses lower phase error and higher accuracy. The simulations and two experiments are carried out to testify the proposed method. From the experimental results of the static object, we find that the standard deviation of the proposed method is better than that of the traditional one. The dynamic experiment of a moving lampshade shows that the time resolution of our method is the same as the CCD. As a real-time quantitative dynamic measurement method, it can be applied in various fields.

In this research, we aim to develop a method to recognize three dimensional shape of stacked rubbles each by each for rubble withdrawal rescue robots. Shapes, masses, states of stacked rubbles and so on are various and unknown at disaster areas. Then, grasping positions on rubbles and ways to remove them have to be considered for not breaking down the stacked rubbles and falling them down on victims. Thus, it is necessary to recognize stacked rubble individually and to identify their features, such as shapes, masses, center of gravity positions and so on. In this paper, we propose a 3-D object shape recognition system with a RGB-D sensor and a 3-D reference marker. Moreover, we also propose an extraction method of rubbles using the SSD (Single Shot Multi Box Detector) of the AI (Artificial Intelligence). Experiments were performed to confirm the validity of the proposed method with our constructed prototype of a rescue robot. Through the experiments, it is shown that target stacked rubbles were recognized individually.

We propose a design for a high sensitivity plasmon resonance (SPR) sensor based on photonic crystal fiber (PCF) and analyze the sensor using finite element software (FEM). By introducing a D-shape hole instead of a circular hole in the first ring of the photonic crystal fiber, which increases the coupling effect and proficient infiltration of the sensing, resulting in enhance the performance of the sensor due to the flat structure of the D-shape hole and the homogeneous metal coating facility. We study the influence of the parameters of the D-shape hole on the sensing performance and analyze the sensor performance based on the wavelength and amplitude sensitivity. The results show that the proposed sensor is capable of detecting analyte refractive index ranging from 1.30 to 1.42, and the maximum sensitivities of 14,600 nm/RIU and 1475 RIU−1 can be achieved in this sensing range, respectively. The largest sensor resolutions for wavelength and amplitude sensing are 6.84 × 10 − 6 and 6.78 × 10 − 6 RIU , and the maximum figure of merits (FOM) of the proposed sensor being 618.

Sacrococcigeal pilonidalis disease (SPD) recurrence is a major factor influencing surgical outcomes. Several different surgical treatments have been reported, however, there is a lack of long-term data on reoperation. Aim of this study was to analyze outcomes of a single center adopting a standardized off-midline asymmetric procedure (D-shape). Analytic longitudinal assessment of 83 patients (median age 35years, range 23–59years) with recurrent SPD that completed the 5-year study design following D-shape reoperation. Among a cohort of 607 patients, we enrolled 83 recurrent SPD. After D-shape reoperation, second recurrence rate was 9.6% (8/83). Second recurrence rate was not statistically significantly different among patients undergone D-shape as first surgery compared to patients of symmetric excision group (11.8% vs. 7.4%, p = 0.57). Similarly, there was no statistical difference among patients who underwent D-shape as first surgery compared to patients who underwent symmetric excision elsewhere (11.8% vs. 9.1%, p =.75). D-shape is a safe and effective when adopted as revisional surgery at a long-term follow-up. Comparative evaluation is warranted to establish the potential superiority over different surgical surgery in case of recurrence.

We present a novel active learning approach for shape cosegmentation based on graph convolutional networks (GCNs). The premise of our approach is to represent the collections of three-dimensional shapes as graph-structured data, where each node in the graph corresponds to a primitive patch of an oversegmented shape, and is associated with a representation initialized by extracting features. Then, the GCN operates directly on the graph to update the representation of each node based on a layer-wise propagation rule, which aggregates information from its neighbors, and predicts the labels for unlabeled nodes. Additionally, we further suggest an active learning strategy that queries the most informative samples to extend the initial training samples of GCN to generate more accurate predictions of our method. Our experimental results on the Shape COSEG dataset demonstrate the effectiveness of our approach.

Our study aimed to correlate the overall 3-dimensional (3-D) shape of the breast to the compensation depth to produce a homogeneous dose distribution using the electronic tissue compensation (ECOMP) treatment technique. The study involved creating a number of semioval water phantoms with the diameter of the larger axis representing the breast separation and the shorter axis representing the distance from the chest wall to the apex of the breast. Multiple plans with 2 tangential fields were created for each phantom using different transmission penetration depths (TPDs) to determine the optimum TPD value based on the evaluation of dose uniformity and maximum hot spot. Optimum TPD values from the semioval water phantom plans were plotted on a graph as a function of separation and radius and were used as guidelines to choose the optimum TPD for the breast patient's cases. A total of 10 patients who had been treated with radiation therapy using ECOMP tangential fields were randomly selected. The separation and the radius of the breast were measured for 3 regions (superior, middle, and inferior) to retrospectively determine the optimum TPD from the graph for each region. These TPD values were then used to plan the breast cases. For all the patients studied, the optimized TPD technique produced a lower average homogeneity index (HI) value of 0.658 than the standard ECOMP technique of 0.856. These results showed that optimized TPD technique produced a more homogeneous dose distribution than the standard ECOMP technique. By measuring the breast size based on breast separation and the chest wall-to-apex distance at different locations along the superior-inferior axis of the breast, the optimum TPD can be determined at each location to provide a homogeneous dose distribution. A module can be created within the planning system to automatically assign the optimum TPD for both tangential fields so uniform fluence maps can be achieved throughout the whole breast volume. This method can serve as a guideline in ECOMP during the treatment planning to obtain a homogeneous dose distribution.

We present a probabilistic framework for detailed 3-D shape estimation and tracking using only vision measurements. Vision detections are processed via a bird’s eye view representation, creating accurate detections at far ranges. A probabilistic model of the vision based point cloud measurements is learned and used in the framework. A 3-D shape model is developed by fusing a set of point cloud detections via a recursive Best Linear Unbiased Estimator (BLUE). The point cloud fusion accounts for noisy and inaccurate measurements, as well as minimizing growth of points in the 3-D shape. The use of a tracking algorithm and sensor pose enables 3-D shape estimation of dynamic objects from a moving car. Results are analyzed on experimental data, demonstrating the ability of our approach to produce more accurate and cleaner shape estimates.

The microstructure of Sn-Ag-Cu (SAC) solder joints plays an important role in the reliability of electronics, and interlaced twinning has been linked with improved performance. Here, we study the three-dimensional (3-D) shape of interlaced regions in Sn-3.0Ag-0.5Cu (SAC305) solder balls by combining serial sectioning with electron backscatter diffraction. In solder balls without large Ag3Sn plates, we show that the interlaced volume can be reasonably approximated as a hollow double cone with the common 〈100〉 twinning axis as the cone axis, and the 〈110〉 from all three twinned orientations making up the cone sides. This 3-D morphology can explain a range of partially interlaced morphologies in past work on 2-D cross-sections.

D-shape SÌ3N4 waveguides are fabricated by dielectric lift-off process. We measure ultra-low loss for a 90nm-thick core of 2.42 dB/m at 1550 nm and a loaded Q-factor of 1.12x106 for a 0.8 mm radius resonator.

With the nano-composite materials gaining momentum in the optical field, a new nano-composite filled D shape Photonic Crystal Fiber (PCF) is designed and the various optical properties are investigated with help of Finite Element Method. In the proposed structure the D-shape PCF is made up of silica with embedded silver nanoparticles and air holes are distributed along the fibre. The designed fibre shows various optical properties such as dispersion, birefringence, beat length and loss with respect to wavelength and compared with different filling factor like 0.1, 0.3 and 0.5. From our estimation and comparative analysis, it has been proved that the fibre loss has been decreased with increasing filling factor. Further this also showed flat dispersion at maximum filling factor. Keywords: Nanoparticles, Nano-composite, Dispersion, Birefringence, Beat length

We propose an elliptic core effective D-shaped fiber with air hole assistant for birefringence applications. The proposed birefringent fiber works on the principle of asymmetric core region. The birefringence of the proposed D-shaped fiber has been numerically investigated in detail. The designed fiber has effective mode areas of 16.04 μm2 and 16.06 μm2 for x-and y-polarization modes, respectively, at a wavelength of 1550 nm. Our numerical results reveal a birefringence and confinement loss of 2.25 × 10−4 and 6.66 × 10−3 dB/m respectively at 1550 nm wavelength. The proposed fiber exhibits a dispersion variation of 1.3 ps/km-nm and 1.57 ps/km-nm respectively for x-and y-polarizations over a wavelength band of 200 nm ranging from 1.4 to 1.6 μm. We have also investigated the influence of variation in the fiber parameters on the birefringence and dispersion. Furthermore, we have calculated the fabrication tolerances, the variation of birefringence value is very small by varying the air hole diameters of the fiber. We believe that the reported results have potential importance in the design and development of polarization control devices applicable in fiber-optic sensors.

The 3-D measurement of rail shape is important for the safety of railway transportation. Phase Measurement Profilometry (PMP) is chosen to measure rail shape in this paper for its advantages of non-contact, high accuracy and fast speed. In traditional Phase Measurement Profilometry (T-PMP), the setting of the reference plane plate plays an important role, and it is a critical step to capture the reference fringe pattern projected onto the reference plane plate. However, it is sometimes difficult to choose or place the physical reference plane plate in practical applications with complex environments, such as in rail shape measurement. In this paper, a novel PMP based on virtual reference fringe (VRF-PMP) is proposed to deal with the problem. The virtual reference fringe is obtained through extending a partial undeformed fringe pattern intercepted from the whole fringe pattern using image interpolation methods, including Nearest Interpolation, Bilinear Interpolation, Bicubic Interpolation and a proposed One-dimensional New Edge-directed Interpolation (ONEDI). Simulation and experimental results show that VRF-PMP can reconstruct the 3-D shape of rail effectively without a physical reference plane plate. This paper provides a new suggestion for actual detection by PMP.

The first sector of the ITER vacuum vessel (VV) has been delivered to the ITER Organization. One of the critical manufacturing steps is d -shape assembly. The manufactured four poloidal segments (PS 1, 2, 3, 4) are assembled, and then form the d -shape structure with a height of 11.4 m. Each PS is a complex and heavy double-wall structure with an inner shell and outer shell, poloidal and toroidal ribs, and in-wall shielding blocks are filled inside of the double wall as radiation shield. Thus, it is quite difficult to handle for assembly in keeping with the segment final dimensional status, so that it is necessary to set a practical plan. Before conducting actual assembly, the d -shape is virtually fitted using all results of final 3D metrology on each PS. In detail, each inner shell as-built result on four interfaces, plus a margin for welding shrinkage and gap for welding are considered to set the d -shape fit-up reference. To set each PS in the right position as comparing the fit-up reference, the fiducial posts (FPs) on each PS are measured using a 3D metrology system. After done the fit-up on the assembly plate, whole FPs (55 ea.) are checked as verification. As a result, the PS2 and PS4 are shifted Avg 7.4 mm and Avg 7 mm to the poloidal way, respectively. After finished inner shell welding, the whole FPs are also measured. The PS2 and PS4 are still shifted Avg 1.4 mm and Avg 0.8 mm to poloidal way, respectively. Eventually, the as-built dimension on the important part is evaluated with given tolerance as a preliminary prediction of the final d -shape result.

Considering the complex electromagnetic environments of the D shape vacuum vessel (VV) with plasma facing components (PFCs), it’s necessary to build a monitoring system to obtain the strain and temperature data. This work presents a preliminary study on measuring temperature, strain and displacement of PFCs using Fiber Bragg Grating (FBG) sensors. In this experiment, a sub-system with ten FBG sensors was built to research the multi-parameters measurement in high temperature and vacuum conditions. The data of stain, temperature and deformation were acquired successfully with a high precision. In order to prove the results of the experiment, thermomechanical analyses have been carried out and the calculation results were consistent with the experimental results, which provides a base for the further work.

The light irradiated into a translucent object is multi-reflected inside and then emitted from a position different from the incident position. This behavior is called subsurface scattering. Understanding subsurface scattering behavior is very important in the measurement of three-dimensional (3-D) shapes and CG representations of translucent objects. In this study, we simulated the subsurface scattering of translucent objects using the ray tracing method, and examined a shape-measurement method for 3-D translucent objects by the spotlight projection method using the simulation results.

At present, the numerical simulation on the aerodynamic response and force of the iced conductor are mainly based on the quasi steady criterion, which ignored the interaction between the conductor and the flow field. This paper presents a numerical study of three kinds of fluid-structure interaction models for D-shape conductor. The effects of reduced velocity, degree of freedom and wind attack angle on aerodynamic response of the iced conductor are discussed. The results show that the rotational freedom has certain influence on the across-wind vibration. The mean value of drag coefficient decreases with the increase of wind attack angle, while the lift and moment coefficient increase with the increase of wind attack angle. When the maximum amplitude of vibration displacement occurs, the corresponding reduced velocity is not entirely consistent with that of the maximum aerodynamic force.

We propose a deformed microcavity laser, where a high-Q mode group emits unidirectionally. The cavity comprises three circular arcs and one linear section. To minimize diffraction effects from the boundary, three circular arcs and one linear section are tangentially connected. By adjusting the sizes and the positions of the two sub-circular arcs, unidirectionality is maximized. In an experiment with an InP based InGaAsP semiconductor microcavity laser, a lasing mode group localized on aperiod-7 unstable periodic orbit emits unidirectionally. In our resonance calculation, a high-Q factor is confirmed.

Robotic grinding is a promising technique to generate the final shape of blades. It can relieve human from participating in dirty and noisy environments, improve product quality, and lower production costs. One important task in robotic grinding is 3-D shape matching. However, existing matching methods do not consider the requirements associated with different grinding allowances, which can potentially lead to an unstable grinding force. This paper proposes a novel shape matching method for robotic grinding. The goal is to define a new objective function considering different allowance weights for stable grinding, and address incorrect shape matching from the missing points or uneven density points. The main contribution of this paper is the application of variance minimization to construct an objective function, from which the required shape matching parameters are iteratively calculated. This method balances the contributions of all the measured points, weighs the allowances for the pressure and suction surfaces of a blade, and avoids incorrect matching tendencies for high-density points. It is advantageous to maintaining a relatively stable grinding force. The effectiveness of this method is verified through simulations and scanning/grinding experiments of different blades.

A novel surface plasmon resonance sensor (SPR) based on D-shaped photonic crystal fiber (PCF) is designed for sensing low refractive indexes, and its performance is investigated numerically by the finite element method (FEM). Indium tin oxide (ITO) is chosen as the plasmonic materials to expand the operating wavelength range of the PCF-SPR sensor to the infrared region. Spectral sensitivities of 2000–15000 nm/RIU for refractive indexes of 1.22-1.33 are validated in the wavelength range of 1200–2250 nm,and the maximum amplitude sensitivity up to 442.47 RIU−1 is obtained at 2,010 nm with a high resolution of 6.67 × 1 0 − 6 RIU. Therefore, the sensor can effectively monitor subtle variations of low refractive indexes and, has enormous commercial value for biomedical and organic detection and related applications.

We designed a temperature sensor by using a D-shape fiber coated with indium tin oxide as a sensing probe. D-shape fiber was fabricated out of conventional single mode fiber by a homemade setup using wheel polishing technique. Insertion loss of D-shape fiber was about 3.5 dB. ITO was deposited over the D-shape fiber by electron-beam deposition technique to have precise deposition of 60nm thin film over the D-shape region of fiber to be utilized as a sensor. It is observed that the transmitted power increased with the increase in temperature with a sensitivity of 0. 0013 dBm/°C. The proposed sensor also provides a good linearity and stability.

We demonstrated a Q-switched Erbium-doped fiber laser (EDFL) using indium-tin-oxide (ITO) deposited onto D-shape fiber as a saturable absorber (SA). The D-shaped fiber was prepared using polishing wheel technique while the ITO was deposited onto the polished surface using electron beam deposition technique to establish excellent evanescent field interaction between the material and light on the surface of the polished region. The SA device was deployed into EDFL ring cavity to generate Q-switched pulses operating at 1566.4 nm. It was able to initiate pulses as short as 2.3 µs with the highest repetition rate of 52.77 kHz. Stability of the SA is proven as it produced stable pulses within the pump power of 55.2–96.4 mW with signal to noise ratio of 58.6 dB. Q-switched EDFL generates pulses with the output power of 300 µW and pulse energy of 5.68 nJ at 96.4 mW pump power. Therefore, ITO deposited onto D-shape fiber can be deployed as SA in EDFL cavity for portable Q-switched laser source.

We demonstrate precise passive rotational alignment of multi-core fibres (MCFs) with double-D-shape cladding on V-groove arrey. Eight MCFs were simultaneously aligned with small rotational misalignments, and achieved the insertion losses of < 0.5 dB in 16 outer cores.

The deformable warhead is a common type of anti-missile warheads, and the geometric configuration of deformable warhead is close to D shape under the lateral blast loading of auxiliary charge. In this article, the spatial distribution of fragments is taken as the research object, and an empirical model for evaluating the spatial distribution of fragments is expected to be established. First, the empirical model was designed based on dimensional analysis and quadratic interpolation. Then, three different D-shaped structures (D-90°, D-120°, D-150°) were studied by the numerical simulations and experiments. In order to minimize the influence of the axial sparse waves at both ends, only the middlemost layer of fragments was researched. The relationships among d / r , sin α , and sin β were obtained (where d represents the initiation distance, α represents the initial position angle, and β represents the scattering angle). With the scattering angle β and target distance l , the spatial distribution of fragments can be deduced. Based on the fitting formula and the parameters of D-shaped structures, the relationships between d / r , sin α , and sin β of arbitrary D-shaped casing (D- θ ) were obtained using quadratic interpolation. Finally, D-105° structure was verified by numerical simulation and empirical formula, both of which coincided well with each other. Therefore, the empirical model can be used to rapidly evaluate the spatial distribution of fragments, especially suitable for the D-shaped structure with a large length–diameter ratio.

Robot-assisted deployment of fenestrated stent grafts in Fenestrated Endovascular Aortic Repair (FEVAR) requires accurate geometrical alignment. Currently, this process is guided by 2D fluoroscopy, which is uninformative and error prone. In this paper, a real-time framework is proposed to instantiate the 3D shape of a fenestrated stent graft based on only a single low-dose 2D fluoroscopic image. Firstly, the fenestrated stent graft was placed with markers. Secondly, the 3D pose of each stent segment was instantiated by the RPnP (Robust Perspective-n-Point) method. Thirdly, the 3D shape of the whole stent graft was instantiated via graft gap interpolation. Focal-Unet was proposed to segment the markers from 2D fluoroscopic images to achieve semi-automatic marker detection. The proposed framework was validated on five patient-specific 3D printed phantoms of aortic aneurysms and three stent grafts with new marker placements, showing an average distance error of 1-3mm and an average angle error of 4 degree., Comment: 7 pages, 10 figures

The fluorescence in situ (FISH) belongs to the most often used molecular cytogenetic techniques, applied in many areas of diagnosis and research. The analysis of FISH images relies on localization and counting the red and green spots in order to determine HER2 status of the breast cancer samples. The algorithm of spot localization presented in the paper is based on 3-D shape analysis of the image objects. The subsequent regions of the image are matched to the reference pattern and the results of this matching influence localization of spots. The paper compares different shapes of the reference pattern and their efficiency in spot localization. The numerical experiments have been performed on the basis of 12 cases (patients), each represented by three images. Few thousands of cells have been analysed. The quantitative analyses comparing different versions of algorithm are presented and compared to the expert results. The best version of the procedure provides the absolute relative difference to the expert results smaller than 3%. These results confirm high efficiency of the proposed approach to the spot identification. The proposed method of FISH image analysis improves the efficiency of detecting fluorescent signals in FISH images. The evaluation results are encouraging for further testing of the developed automatic system directed to application in medical practice.

This letter introduces a robust representation of 3-D shapes, named DeepPano, learned with deep convolutional neural networks (CNN). Firstly, each 3-D shape is converted into a panoramic view, namely a cylinder projection around its principle axis. Then, a variant of CNN is specifically designed for learning the deep representations directly from such views. Different from typical CNN, a row-wise max-pooling layer is inserted between the convolution and fully-connected layers, making the learned representations invariant to the rotation around a principle axis. Our approach achieves state-of-the-art retrieval/classification results on two large-scale 3-D model datasets (ModelNet-10 and ModelNet-40), outperforming typical methods by a large margin.