5,733 research outputs found
Dynamic response of orthogonal 3D woven carbon composites under soft impact
This paper presents an experimental and numerical investigation into the dynamic response of 3D orthogonal woven carbon composites undergoing soft impact. Composite beams of two different fibre architectures, varying only by the density of through-thickness reinforcement, were centrally impacted by metallic foam projectiles. Using high speed photography, the centre-point back-face deflection was measured as a function of projectile impulse. Qualitative comparisons are made with a similar uni-directional laminate material. No visible delamination occurred in orthogonal 3D woven samples, and beam failure was caused by tensile fibre fracture at the gripped ends. This contrasts with uni-direction carbon fibre laminates, which exhibit a combination of wide-spread delamination and tensile fracture. Post-impact clamped-clamped beam bending tests were undertaken across the range of impact velocities tested in order to investigate any internal damage within the material. Increasing impact velocity caused a reduction of beam stiffness: this phenomenon was more pronounced in composites with a higher density of through-thickness reinforcement. A three-dimensional finite element modelling strategy is presented and validated, showing excellent agreement with the experiment in terms of back-face deflection and damage mechanisms. The numerical analyses confirm negligible influence from though-thickness reinforcement in regards to back-face deflection, but significant reductions in delamination damage propagation. Finite element modelling was used to demonstrate the significant structural enhancements provided by the through-the-thickness weave. The contributions to the field made by this research include the characterisation of 3D woven composite materials under high-speed soft impact, and the demonstration of how established finite element modelling methodologies can be applied to the simulation of orthogonal woven textile composite materials undergoing soft impact loading
Prediction of heme binding residues from protein sequences with integrative sequence profiles
Single-Image-Based Deep Learning for Segmentation of Early Esophageal Cancer Lesions
Accurate segmentation of lesions is crucial for diagnosis and treatment of
early esophageal cancer (EEC). However, neither traditional nor deep
learning-based methods up to today can meet the clinical requirements, with the
mean Dice score - the most important metric in medical image analysis - hardly
exceeding 0.75. In this paper, we present a novel deep learning approach for
segmenting EEC lesions. Our approach stands out for its uniqueness, as it
relies solely on a single image coming from one patient, forming the so-called
"You-Only-Have-One" (YOHO) framework. On one hand, this "one-image-one-network"
learning ensures complete patient privacy as it does not use any images from
other patients as the training data. On the other hand, it avoids nearly all
generalization-related problems since each trained network is applied only to
the input image itself. In particular, we can push the training to
"over-fitting" as much as possible to increase the segmentation accuracy. Our
technical details include an interaction with clinical physicians to utilize
their expertise, a geometry-based rendering of a single lesion image to
generate the training set (the \emph{biggest} novelty), and an edge-enhanced
UNet. We have evaluated YOHO over an EEC data-set created by ourselves and
achieved a mean Dice score of 0.888, which represents a significant advance
toward clinical applications
Coordinating a multi-retailer decentralized distribution system with random demand based on buyback and compensation contracts
Purpose: The purpose of this paper is to set up the coordinating mechanism for a
decentralized distribution system consisting of a manufacturer and multiple independent
retailers by means of contracts. It is in the two-stage supply chain system that all retailers sell an
identical product made by the manufacturer and determine their order quantities which directly
affect the expected profit of the supply chain with random demand.
Design/methodology/approach: First comparison of the optimal order quantities in the
centralized and decentralized system shows that the supply chain needs coordination. Then the
coordination model is given based on buyback cost and compensation benefit. Finally the
coordination mechanism is set up in which the manufacturer as the leader uses a buyback policy
to incentive these retailers and the retailers pay profit returns to compensate the manufacturer.
Findings: The results of a numerical example show that the perfect supply chain coordination
and the flexible allocation of the profit can be achieved in the multi-retailer supply chain by the
buyback and compensation contracts.
Research limitations: The results based on assumptions might not completely hold in practice
and the paper only focuses on studying a single product in two-stage supply chain Practical implications: The coordination mechanism is applicable to a realistic supply chain
under a private information setting and the research results is the foundation of further
developing the coordination mechanism for a realistic multi-stage supply chain system with
more products.
Originality/value: This paper focused on studying the coordination mechanism for a
decentralized multi-retailer supply chain by the joint application of the buyback and
compensation contracts. Furthermore the perfect supply chain coordination and the flexible
allocation of the profit are achieved.Peer Reviewe
Coordinating a multi-retailer decentralized distribution system with random demand based on buyback and compensation contracts
Purpose: The purpose of this paper is to set up the coordinating mechanism for a
decentralized distribution system consisting of a manufacturer and multiple independent
retailers by means of contracts. It is in the two-stage supply chain system that all retailers sell an
identical product made by the manufacturer and determine their order quantities which directly
affect the expected profit of the supply chain with random demand.
Design/methodology/approach: First comparison of the optimal order quantities in the
centralized and decentralized system shows that the supply chain needs coordination. Then the
coordination model is given based on buyback cost and compensation benefit. Finally the
coordination mechanism is set up in which the manufacturer as the leader uses a buyback policy
to incentive these retailers and the retailers pay profit returns to compensate the manufacturer.
Findings: The results of a numerical example show that the perfect supply chain coordination
and the flexible allocation of the profit can be achieved in the multi-retailer supply chain by the
buyback and compensation contracts.
Research limitations: The results based on assumptions might not completely hold in practice
and the paper only focuses on studying a single product in two-stage supply chain Practical implications: The coordination mechanism is applicable to a realistic supply chain
under a private information setting and the research results is the foundation of further
developing the coordination mechanism for a realistic multi-stage supply chain system with
more products.
Originality/value: This paper focused on studying the coordination mechanism for a
decentralized multi-retailer supply chain by the joint application of the buyback and
compensation contracts. Furthermore the perfect supply chain coordination and the flexible
allocation of the profit are achieved.Peer Reviewe
2,5-DibromoÂterephthalic acid dihydrate
The asymmetric unit of the title compound, C8H4Br2O4·2H2O, contains one half-molÂecule of 2,5-dibromoÂterephthalic acid (DBTA) and one water molÂecule. The DBTA molÂecule is centrosymmetric. In the crystal structure, interÂmolecular O—Hâ‹ŻO hydrogen bonds link the molÂecules, forming a three-dimensional framework
Construction, expression, and characterization of rSEA-EGF and in vitro evaluation of its antitumor activity against nasopharyngeal cancer
- …