The Effect of Tin Content on the Strength of a Carbon Fiber/Al-Sn-Matrix Composite Wire

The effect of tin content in an Al-Sn alloy in the range from 0 to 100 at.% on its mechanical properties was studied. An increase in the tin content leads to a monotonic decrease in the microhardness and conditional yield stress of the Al-Sn alloy from 305 to 63 MPa and from 32 to 5 MPa, respectively. In addition, Young’s modulus and the shear modulus of the Al-Sn alloy decreases from 65 to 52 GPa and from 24 to 20 GPa, respectively. The effect of tin content in the Al-Sn matrix alloy in the range from 0 to 50 at.% on the strength of a carbon fiber/aluminum-tin-matrix (CF/Al-Sn) composite wire subject to three-point bending was also investigated. Increasing tin content up to 50 at.% leads to a linear increase in the composite wire strength from 1450 to 2365 MPa, which is due to an increase in the effective fiber strength from 65 to 89 at.%. The addition of tin up to 50 at.% to the matrix alloy leads to the formation of weak boundaries between the matrix and the fiber. An increase in the composite wire strength is accompanied by an increase in the average length of the fibers pulled out at the fracture surface. A qualitative model of the relationship between the above parameters is proposed.

BGM-Net: Boundary-Guided Multiscale Network for Breast Lesion Segmentation in Ultrasound

Automatic and accurate segmentation of breast lesion regions from ultrasonography is an essential step for ultrasound-guided diagnosis and treatment. However, developing a desirable segmentation method is very difficult due to strong imaging artifacts e.g., speckle noise, low contrast and intensity inhomogeneity, in breast ultrasound images. To solve this problem, this paper proposes a novel boundary-guided multiscale network (BGM-Net) to boost the performance of breast lesion segmentation from ultrasound images based on the feature pyramid network (FPN). First, we develop a boundary-guided feature enhancement (BGFE) module to enhance the feature map for each FPN layer by learning a boundary map of breast lesion regions. The BGFE module improves the boundary detection capability of the FPN framework so that weak boundaries in ambiguous regions can be correctly identified. Second, we design a multiscale scheme to leverage the information from different image scales in order to tackle ultrasound artifacts. Specifically, we downsample each testing image into a coarse counterpart, and both the testing image and its coarse counterpart are input into BGM-Net to predict a fine and a coarse segmentation maps, respectively. The segmentation result is then produced by fusing the fine and the coarse segmentation maps so that breast lesion regions are accurately segmented from ultrasound images and false detections are effectively removed attributing to boundary feature enhancement and multiscale image information. We validate the performance of the proposed approach on two challenging breast ultrasound datasets, and experimental results demonstrate that our approach outperforms state-of-the-art methods.

Electrochemical Deposition of SiO2-Coatings on a Carbon Fiber

Research on carbon fiber oxide coatings is primarily focused on metal matrix composites. Such coatings act as a diffusion barrier between a matrix and a fiber and, in addition, they can be weak boundaries that significantly increase the mechanical properties of metal matrix composites. A simple and economical method of coating deposition is the sol–gel method. However, it does not allow for control of the thickness of the carbon fiber coating. To eliminate this limitation, a combined method is used that includes sol–gel technology and electrochemical deposition. The paper presents the results of studies on the production of SiO2 coatings on carbon fibers by the above method. The effect of current density, deposition time, salt concentration, pH of the reaction medium, TEOS/H2O molar ratio, and alcohol concentration in the reaction medium on the structure and thickness of the coatings was studied.

OH + OKAY in informing sequences: On fuzzy boundaries in a particle combination

This study explores fuzzy boundaries, or weak cesuras, in the particle combination OH + OKAY as used in informing sequences in ordinary English talk-in-interaction. The focus is on the third position in such sequences, where OH + OKAY responds to information that has been solicited by the speaker in a prior turn. Based on a collection of approximately 45 instances of OH + OKAY in recent American English telephone and face-to-face interactions, this study adopts the methodology of Conversation Analysis and Interactional Linguistics to examine the prosody and phonetics of OH + OKAY as a feature of turn design. It asks: (i) when does the speaker use a combination of OH and OKAY in the third position rather than a simple OH or OKAY? and (ii) to what extent does the prosodic–phonetic delivery of OH + OKAY contribute to an interpretation of what the turn is doing? The study finds that (i) OH + OKAY is used when responding to a solicited informing that not only supplies information but also accomplishes another action with consequences for the recipient and (ii) if OH + OKAY is delivered with a strong cesura between its parts, its actions are distributed in separate turn-constructional units, creating a multi-unit turn that proposes sequence closure. If the cesura in OH + OKAY is weak, the component parts are fused into a compound particle that can preface more talk by the same speaker. Weak boundaries between OH and OKAY can be exploited by participants for the purposes of turn construction and epistemic positioning.

Osłabiona granica – ekspresje świata demonicznego w przestrzeni domu na podstawie przekazów folklorystycznych i etnograficznych z XIX i XX wieku

Weakened Border – Expressions of Demonic World in the House Space in the Folklore and Ethnographic Materials from the 19th and the 20th Century The article focuses on three issues: folk beliefs related to the house, magic protecting the house against demonic creatures, and the so‑called “weak boundaries”. “Weak boundaries” are places through which demonic figures enter the human world. These are mostly slits – slots in the walls, a chimney, a keyhole or a window. Small holes can be interpreted as symbols of inversion and amorphousness of the underworld.

Radon Transform based Modified Nonlinear Access for Segmentation of Mammogram Application

In this paper a novel and application oriented mammogram segmentation using Nonlinear level set method and Radon Transform proposed. Handling medical images as a part of segmentation issues plays a critical phase. The proposed approach of nonlinear method of segmentation for which specific images of mammogram are consideredusing probability weighted force stopping function and Bayesian rules to extract the weak boundaries. This proposed method leads to get true extract boundaries and also minimizes the boundary leakagesusing this approach.The experiment demonstration with suitable images are performed on LSF

Transformational leadership and polychronicity as antecedents of work-home boundaries

Purpose This paper aims to bring together leadership and boundary theories to conceptualize how transformational leadership behaviors and polychronicity might impact our life satisfaction through the boundaries we maintain around our work and home domains. It is argued that transformational behavior of the supervisor will be negatively associated with the strength of boundary that the followers construct around their home domain but will be positively associated with the boundary strength around the work domain. Additionally, it is posited that polychronicity will be negatively associated with the boundary strengths at home and at work but will be positively related with life satisfaction. Design/methodology/approach The concepts of leadership, polychronicity and work-home boundaries are explained, and logical arguments are presented to develop a conceptual framework incorporating these constructs. Findings The conceptual exploration of this study denotes that transformational leadership of supervisors would positively impact the life satisfaction of employees, directly as well as through the boundaries around their work and home domains. Specifically, transformational leadership behaviors of supervisors are expected to be associated with followers’ strong work boundaries but with weak home boundaries. At the same time, highly polychronic individuals are expected to keep weak boundaries around their work and home domains and to have higher life satisfaction. Research limitations/implications The conceptualization of this paper focused on constructs that have not been linked before in one framework. As such, empirical research is suggested to validate the model. Practical implications Understanding the antecedents of life satisfaction of employees is of crucial interest to managers at workplaces. It is suggested that managers should engage employees in co-constructing their work and home boundaries, with a view to increasing the life satisfaction of employees. Further, it seems possible that the hitherto prevalent practice of fostering strong boundaries at work may be hindering the well-being of employees. Social implications Variables active at workplaces, such as polychronicity, also affect the non-work domain and, thereby, the life satisfaction of employees. Originality/value Through this conceptualization, this paper has attempted to fill a gap in boundary management literature by linking transformational leadership of the supervisor to the work and home boundaries of the followers. This study also situates polychronicity as an important player in the work-home interface and life satisfaction of employees. This research links transformational leadership, polychronicity, boundary management and life satisfaction in one model. It thereby contributes to the leadership literature and extends the nomological network of work-non-work boundary management.

Fracture Segmentation Method Based on Contour Evolution and Gradient Direction Consistency in Sequence of Coal Rock CT Images

The coal rock exhibits obvious heterogeneity and anisotropy after a long-term geological evolution in nature. Therefore, the coal rock CT (computed tomography) image shows uneven grey scale, low contrast, and the fractures with weak boundaries. The accurate segmentation of the coal rock fracture networks is challenging. In this paper, a segmentation method of fractures based on contour evolution and gradient direction consistency is proposed to accurately segment the fracture networks in the sequence of coal rock CT images. According to the contour variation rule of the fractures in the discrete 3D (three dimensional) space formed by the sequence of CT images, the fracture contour evolution model (FCEM) is constructed and the preliminary segmentation results of fractures are obtained from FCEM. A 3D adaptive median filtering (3DAMF) and a 3D bilateral filtering (3DBF) are proposed. The high density miscellaneous point noises in the coal rock CT images are filtered by the 3DAMF. And the boundaries of fractures are enhanced by 3DBF. According to the similarity of the preliminary segmentation results of fractures and the real contours of fractures, the preliminary segmentation results of fractures are optimized based on the gradient direction consistency model (GDCM) proposed in this paper to obtain the accurate boundaries of fractures. The fracture segmentation method proposed in this paper can obtain accurate boundaries of fractures with weak boundaries, and the experimental results show that the segmentation efficiency for sequence is high and adaptability is strong.

Image Segmentation Using Contour Models

Image segmentation is an important task in image processing, which is widely used in medical applications such as abnormality detection and after treatment progress monitoring. Conventionally, texture, region, and edge information are used for segmentation. Recently, the majority of image segmentation uses contour-based models. The problem of efficient segmentation in medical images is of great importance in disease diagnosis. Medical images suffer from weak boundaries, and placement of initial contour is a major issue. Level method is an effective method for segmentation of image as it has ability to tackle complex geometries. It helps to detect the precise location of the target region and help to prevent the boundary leakage problem. This chapter presents an overview of the advanced region and edge-based level set segmentation algorithms and their application in the dental x-ray images. Computer-aided diagnosis from x-ray images are of interest to clinicians in detection and accurate decision making. Case studies of multiple region segmentation from dental x-rays are presented.