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Geometric errors are common in metallic bent tubular parts. Thus, tubes should be inspected and fixed before welding with the joints first. After welding, the relative position of the joints is also necessary to be inspected to judge whether the tube can be assembled reliably. Therefore, the inspection plays an important role in the tube’s assembly. The purpose of this paper is to propose a multi-vision-based system designed to inspect the tube and the relative position of the joints.

For the tube inspection, the small cylinders are taken as the primitives to reconstruct the tube using the multi- vision-based system. Then, any geometric error in the tube can be inspected by comparing the reconstructed models and designed ones. For joints’ inspection, authors designed an adapter with marked points, by which the system can calculate the relative position of the joints.

The reconstruction idea can recognise the line and arc segments of a tube automatically and resolve the textureless deficiency of the tube’s surface. The joints’ inspection method is simple in operation, and any kinds of joints can be inspected by designing the structure of the adapters accordingly.

By experimental verification, the inspection precision of the proposed system was 0.17 mm; the inspection time was within 2 min. Thus, the system developed can inspect a tube effectively and automatically. Moreover, authors can determine how the springback of the arcs behaves, allowing in-process springback prediction and compensation, which can reduce geometric errors in the tubes given the present bending machine accuracy.

The purpose of this paper is to develop a compressive sensing (CS) algorithm for noisy solder joint imagery compression and recovery. A fast gradient-based compressive sensing (FGbCS) approach is proposed based on the convex optimization. The proposed algorithm is able to improve performance in terms of peak signal noise ratio (PSNR) and computational cost.

Unlike traditional CS methods, the authors first transformed a noise solder joint image to a sparse signal by a discrete cosine transform (DCT), so that the reconstruction of noisy solder joint imagery is changed to a convex optimization problem. Then, a so-called gradient-based method is utilized for solving the problem. To improve the method efficiency, the authors assume the problem to be convex with the Lipschitz gradient through the replacement of an iteration parameter by the Lipschitz constant. Moreover, a FGbCS algorithm is proposed to recover the noisy solder joint imagery under different parameters.

Experiments reveal that the proposed algorithm can achieve better results on PNSR with fewer computational costs than classical algorithms like Orthogonal Matching Pursuit (OMP), Greedy Basis Pursuit (GBP), Subspace Pursuit (SP), Compressive Sampling Matching Pursuit (CoSaMP) and Iterative Re-weighted Least Squares (IRLS). Convergence of the proposed algorithm is with a faster rate O(k*k) instead of O(1/k).

This paper provides a novel methodology for the CS of noisy solder joint imagery, and the proposed algorithm can also be used in other imagery compression and recovery.

According to the CS theory, a sparse or compressible signal can be represented by a fewer number of bases than those required by the Nyquist theorem. The new development might provide some fundamental guidelines for noisy imagery compression and recovering.

This paper sets out to give an overview about state‐of‐the‐art optical tomographic image reconstruction algorithms that are based on the equation of radiative transfer (ERT).

An objective function, which describes the discrepancy between measured and numerically predicted light intensity data on the tissue surface, is iteratively minimized to find the unknown spatial distribution of the optical parameters or sources. At each iteration step, the predicted partial current is calculated by a forward model for light propagation based on the ERT. The equation of radiative is solved with either finite difference or finite volume methods.

Tomographic reconstruction algorithms based on the ERT accurately recover the spatial distribution of optical tissue properties and light sources in biological tissue. These tissues either can have small geometries/large absorption coefficients, or can contain void‐like inclusions.

These image reconstruction methods can be employed in small animal imaging for monitoring blood oxygenation, in imaging of tumor growth, in molecular imaging of fluorescent and bioluminescent probes, in imaging of human finger joints for early diagnosis of rheumatoid arthritis, and in functional brain imaging.

This paper aims to provide a shimming method based on scanned data and finite element analysis (FEA) for a wing box assembly involving non-uniform gaps. The effort of the present work is to deal with gap compensation problem using hybrid shims composed of solid and liquid forms.

First, the assembly gaps of the mating components are calculated based on the scanned surfaces. The local gap region is extracted by the seed point and region growth algorithm from the scattered point cloud. Second, with the constraints of hole margin, gap space and shim specification, the optional shimming schemes are designed by the exhaustive searching method. Finally, the three-dimensional model of the real component is reconstructed based on the reverse engineering techniques, such as section lines and sweeping. Using FEA software ABAQUS, the stress distribution and damage status of the joints under tensile load are obtained for optimal scheme selection.

With the scanned mating surfaces, the non-uniform gaps are digitally evaluated with accurate measurement and good visualization. By filling the hybrid shims in the assembly gaps, the joint structures possess similar load capacity but stronger initial stiffness compared to the custom-shimmed structures.

This method has been tested with the interface data of a wing tip, and the results have shown good efficiency and automation of the shimming process.

The proposed method can decrease the manufacturing cost of shims, shorten the shimming process cycle and improve the assembly efficiency.

The purpose of this paper is to investigate the main determinants of consideration in China's non-tradable shares reform. The primary objective is to dig into the institutional factors that affect consideration in China's non-tradable shares reform.

The authors examine a sample of 846 state-owned enterprises (SOEs) that have finished the non-tradable shares reform during 2005-2009. Using the multiple liner regression, the authors discuss the important factors which affect consideration.

The authors find that ownership reconstruction form and capital occupation are very important determinants of consideration. The main factor which affects controlling shareholders’ capital occupation is the form of ownership reconstruction. Capital occupation of incompletely ownership reconstructed companies is more serious than those of complete ownership reconstructed companies. Furthermore, companies of incomplete ownership reconstruction and higher capital occupation paid higher consideration as a compensation for the expropriation of tradable shareholders’ benefit during the shares split period.

This study provides not only a deeper understanding of the reform of non-tradable shares but also an important empirical reference for reform of SOEs in China.

Although proximal row carpectomy, wrist arthrodesis and even total wrist arthroplasty were developed to treat wrist disease using bone and cartilage of the wrist, severe and complicated bone defects caused by ferocious trauma and bone tumors remain a stubborn problem for surgeons. Development and application of the three-dimensional (3D) printing technology may provide possible solutions.

Computed tomography (CT) data of three cases with severe bone defects caused by either trauma or bone tumor were collected and converted into three-dimensional models. Prostheses were designed individually according to the residual anatomical structure of the wrist based on the models. Both the models and prostheses were produced using 3D printing technology. A preoperative design was prepared according to the models and prostheses. Then arthroplasty was performed after preoperative simulation with printed models and prostheses.

The diameter of the stem and radial medullary cavity, the direction and location of the prosthesis, and other components were checked during the preoperative design and simulation process phases. The three cases with 3D printed wrist all regained reconstruction of normal anatomy and part of the function after surgery. The average increasing Cooney score rate of Cases 2 and 3 was 133.34 ± 23.57 per cent, and that of Case 1 reached 85 per cent. The average declining rate of the Gartland and Werley Score in Cases 2 and 3 was 65.21 ± 18.89 per cent, and that of Case 1 dropped to 5 per cent in the last follow-up. The scores indicated that patients experienced pain relief and function regain. In addition, the degree of patient satisfaction improved.

3D printed wrist arthroplasty may provide an effective method for severe and complicated cases without sacrificing other bones. Personal customization can offer better anatomy and function than arthrodesis or other traditional surgical techniques.

The main purpose of this paper is to report the successful treatment modality for patients suffering from arthritis of the metatarsophalangeal joint (MTPJ) of the foot which otherwise could not be treated through traditional surgeries.

The unique capabilities of the computer-aided design and the rapid prototyping (RP) technology are used to develop the customized MTPJ implant (SamKu).

This approach shows good results in the fabrication of the MTPJ implant. Postoperatively, the patient experienced normalcy in the movement of the MTPJ of the foot.

Advanced technologies made it possible to fabricate the customized MTPJ implant (SamKu). The advantage of this approach is that the physical RP model assisted in designing the final metallic implant. It also helped in the surgical planning and the rehearsals.

This case report illustrates the benefits of imaging/computer-aided manufacturing/RP to develop the customized implant and serve those patients who could not be treated in the traditional way. This is a pioneered attempt toward implementation of a customized implant for patients suffering from arthritis of the MTPJ.

The purpose of this paper is to find the optimum inverter type as the solder joint reliability point of view.

In this paper, finite element model(ing) simulations supported with power cycling aging experiments were used to demonstrate the best inverter type as the solder joint reliability point of view.

It was found that inverter types highly affect the solder joint health during its nominal operating.

The authors confirm the originality of this paper.

The war in Croatia has caused very significant damage to chemical and allied industries. This damage has inflicted pollution to soils, groundwaters, major rivers used by third countries for potable water resources, and the Adriatic sea. Emphasizes some of the major issues and indicates remedial action, monitoring requirements, needs for training and joint venture possibilities.

The purpose of this paper is to understand and define the concept of Building Back Better (BBB) and represent it using a comprehensive framework.

Literature related to the concept of BBB were studied to understand the key concepts which constitute BBB. These concepts were analysed and categorised to form the basis of the proposed BBB framework.

Post-disaster recovery in-line with BBB concepts can be achieved by having a holistic view of four key categories: risk reduction entails improving the resilience of the built environment through improvement of structural designs and land-use planning; community recovery includes addressing and supporting psycho-social recovery of communities and supporting economic rejuvenation; implementation addresses ways in which risk reduction and community recovery practices can be put in place in an efficient and effective way; monitoring and evaluation stretches across the first three categories, and calls for putting in place mechanisms to monitor and evaluate recovery activities to ensure compliance with BBB-based concepts and obtain lessons to improve future disaster management practices.

The BBB Framework generated in this study can be used as a foundation to determine best-practice recommendations to implement recovery activities under each of the BBB categories.

The BBB Framework forms a guideline to holistically plan and implement recovery programmes in order to BBB.

A comprehensive guideline or framework which clarified what BBB really means is currently inexistent. This paper addressed this research gap by amalgamating existing information to create a singular framework to simply and comprehensively represent BBB.