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Article ; Online: Adhesive and Cohesive Cracking Analysis of Asphalt Mastics in Contact with Steel Substrates Using an Energy-Based Crack Initiation Criterion

Zhiyang Liu / Haipeng Wang / Jiangcai Chen / Peng Cui

Sustainability, Vol 15, Iss 4415, p

2023 Volume 4415

Abstract: Adhesive and cohesive properties play a vital role in the durability of asphalt mixtures. As a result of the lack of models characterizing adhesive and cohesive cracking, the occurrence of adhesive and cohesive failure has not been fully formulated by ... ...

Abstract	Adhesive and cohesive properties play a vital role in the durability of asphalt mixtures. As a result of the lack of models characterizing adhesive and cohesive cracking, the occurrence of adhesive and cohesive failure has not been fully formulated by using an explicit mechanical approach. Strain energy density in intact mastics is transformed into adhesive and cohesive surface energies as cracks initiate. This study developed an energy-based crack initiation criterion based on the Griffith model and differentiated adhesive and cohesive cracking. The onset of cracking was identified by the deviation of the measured stress from the linear viscoelastic stress. The released strain energy at the crack initiation balanced the increase in surface energies, thus creating a new adhesive and cohesive surface. Several fracture parameters such as initial crack size, cracking stress, and tensile strength were proposed to analyze the effects of sample thickness, strain rate, temperature, and filler concentration in mastics. Results indicate that the adhesive energy, cohesive energy and strain energy density significantly depend on filler concentration in mastic and test temperature but is independent from sample thickness and strain rate. In particular, the variation of the strain energy density from 20 °C to 35 °C reaches 127.4%, and its decrease is up to 46.9% as the filler concentration in the mastic varies from 0 to 60%. The increase in the sample thickness from 160 μm to 1000 μm results in the 150.0% growth of the initial crack size and 74.4% reduction of the cracking stress. Therefore, increasing the adhesive and cohesive energy can essentially improve the toughness to resist the cracking, and decreasing the mastic thickness enhances the loading capacity. It provides a deep understanding of the mixture cracking from a perspective of adhesive and cohesive surface energies.
Keywords	adhesive and cohesive cracking ; crack initiation ; energy-based crack initiation ; surface energy ; Environmental effects of industries and plants ; TD194-195 ; Renewable energy sources ; TJ807-830 ; Environmental sciences ; GE1-350
Subject code	669
Language	English
Publishing date	2023-03-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Stiffening and Toughening of Asphalt Mastic Induced by Bitumen–Mineral Selective Molecular Adsorption and Nanostructural Reconstruction

Zhiyang Liu / Haipeng Wang / Xiangbing Gong / Peng Cui / Hongrui Wei

Sustainability, Vol 15, Iss 4398, p

2023 Volume 4398

Abstract: Asphalt mastic is the most important binder in asphalt mixtures and its rheology is inevitably influenced by the mineral aggregates. Due to the little consideration that has been paid to aggregates’ effects, the rheological properties of mastic films ... ...

Abstract	Asphalt mastic is the most important binder in asphalt mixtures and its rheology is inevitably influenced by the mineral aggregates. Due to the little consideration that has been paid to aggregates’ effects, the rheological properties of mastic films have not been accurately characterized for the present method. Therefore, this study aimed to investigate the rheological characteristics of mastic affected by mineral aggregates and reveal its fundamental mechanism of interfacial interaction. The results suggest that the aggregates increased the stiffness and toughness of mastic within the linear and nonlinear viscoelastic regions. The mastic on limestone had a higher linear viscoelastic modulus than that on basalt below 35 °C, and its ratio reached up to 1.18. However, the modulus of the mastic on basalt surpassed that on limestone by over 50 °C, and the maximum ratio reached 2.17. The mastic in contact with the limestone had a higher failure strain and failure modulus than that in contact with the basalt, the ratios of which reached 1.60 and 1.32, respectively. The macrorheological characteristics are closely related to the nanostructures and intermolecular interactions of bitumen–mineral systems. The coexistence of a stable bitumen nanostructure and an adsorbed layer on the calcite substrate provided a strong bonding energy and high resistance to external shear deformation, leading to the high stiffness and toughness of the limestone. Abundant metal ions from augite and albite diffused into the bitumen layer and destroyed its nanostructure, decreasing the stability of the mastic–basalt interface system. The non-bond energy of bitumen-calcite was 14.15% higher than that of bitumen-albite, and the ratio of shear stress of the bitumen-calcite to the bitumen-albite reached up to 6.8. Therefore, the calcite in limestone reinforced the bitumen, and the augite and albite in basalt destroyed the bitumen colloidal structure. This provides a fundamental understanding of the rheological characterization of mastic on ...
Keywords	asphalt mastics ; rheology ; mineral aggregates ; nanostructure ; molecular dynamics ; Environmental effects of industries and plants ; TD194-195 ; Renewable energy sources ; TJ807-830 ; Environmental sciences ; GE1-350
Language	English
Publishing date	2023-03-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Delay Minimization in RIS-Assisted URLLC Systems under Reliability Constraints

Xiaoyang Song / Yingxin Zhao / Wannan Zhao / Hong Wu / Zhiyang Liu

Entropy, Vol 25, Iss 857, p

2023 Volume 857

Abstract: The ultra-reliable and low-latency communication (URLLC) systems are expected to support the stringent quality of service (QoS) demands in the Internet of Things (IoT) networks. In order to support the strict latency and reliability constraints, it is ... ...

Abstract	The ultra-reliable and low-latency communication (URLLC) systems are expected to support the stringent quality of service (QoS) demands in the Internet of Things (IoT) networks. In order to support the strict latency and reliability constraints, it is preferable to deploy a reconfigurable intelligent surface (RIS) in the URLLC systems to improve the link quality. In this paper, we focus on the uplink of an RIS-assisted URLLC system, and we propose to minimize the transmission latency under the reliability constraints. To solve the non-convex problem, a low-complexity algorithm is proposed by using the Alternating Direction Method of Multipliers (ADMM) technique. The RIS phase shifts optimization, which is typically non-convex, is efficiently solved by formulating as a Quadratically Constrained Quadratic Programming (QCQP) problem. Simulation results verify that our proposed ADMM-based method is able to achieve better performance than the conventional semi-definite relaxation (SDR)-based method with lower computational complexity. Our proposed RIS-assisted URLLC system is able to significantly reduce the transmission latency, which highlights the great potential in deploying RIS in the IoT networks with strict reliability requirements.
Keywords	URLLC ; RIS ; ADMM ; IoT network ; Science ; Q ; Astrophysics ; QB460-466 ; Physics ; QC1-999
Subject code	000
Language	English
Publishing date	2023-05-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Coordination of Retailer-Led Closed Loop Supply Chain Considering Corporate Social Responsibility

Huanhuan Zhao / Yong Liu / Zhiyang Liu

Sustainability, Vol 14, Iss 10851, p

2022 Volume 10851

Abstract: As resource waste and environmental degradation become increasingly serious, closed-loop supply chains have attracted more and more attention from the public. How to effectively undertake corporate social responsibility (CSR) and alleviate the conflict ... ...

Abstract	As resource waste and environmental degradation become increasingly serious, closed-loop supply chains have attracted more and more attention from the public. How to effectively undertake corporate social responsibility (CSR) and alleviate the conflict of closed-loop supply chains has become an urgent task for managers and researchers to resolve. With respect to the coordination problems of closed-loop supply chains led by retailers, based on Stackelberg game theory, we establish some models considering manufacturer’s CSR, exploit them to compare the optimal decisions under centralized and decentralized decisions, explore the impact of CSR on supply-chain decisions, then design a coordination mechanism through two-step pricing.
Keywords	closed-loop supply chain ; corporate social responsibility (CSR) ; two-step pricing ; coordination mechanism ; Environmental effects of industries and plants ; TD194-195 ; Renewable energy sources ; TJ807-830 ; Environmental sciences ; GE1-350
Subject code	330
Language	English
Publishing date	2022-08-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: The Retrospective Study of Magnetic Resonance Imaging Signal Intensity Ratio in the Quantitative Diagnosis of Temporomandibular Condylar Resorption in Young Female Patients

Shaonan Wan / Qi Sun / Qianyang Xie / Minjun Dong / Zhiyang Liu / Chi Yang

Journal of Personalized Medicine, Vol 13, Iss 378, p

2023 Volume 378

Abstract: According to the literature, there is no reliable and quantitative method available for the diagnosis and prognosis of early or potential temporomandibular joint (TMJ) condylar resorption (CR) thus far. The purpose of this study was to raise a new ... ...

Abstract	According to the literature, there is no reliable and quantitative method available for the diagnosis and prognosis of early or potential temporomandibular joint (TMJ) condylar resorption (CR) thus far. The purpose of this study was to raise a new noninvasive method to quantitatively evaluate condylar quality using the signal intensity ratio (SIR) on magnetic resonance imaging (MRI) in order to assist in the diagnosis of TMJ CR. A retrospective exploratory study was performed to compare the condyle-to-cerebral cortex signal intensity ratios (SIR) on MRI among young female patients. We included 60 patients, and they were divided into three groups: the bilateral normal TMJ group (group 1), the bilateral TMJ anterior disc displacement (ADD) but without CR group (group 2), and the bilateral TMJ anterior disc displacement (ADD) with CR group (group 3). The SIR difference between the three groups was analyzed by the Kruskal–Wallis test (K-W test). The sensitivity, specificity, accuracy, and area under curve (AUC) were calculated by the receiver operating characteristic (ROC) curves. There was high consistency between the surgeon and the radiologist in the evaluation of the magnetic signal intensity with intraclass correlation coefficients of 0.939–0.999. The average SIR was 1.07 in the bilateral normal TMJ group (group 1), 1.03 in the ADD without CR group (group 2), and 0.78 in the ADD with CR group (group 3). It could be found by the K-W test that group 3 was significantly different from group 1 and group 2 ( p < 0.05), while there was no significant difference between group 1 and group 2. The optimal critical SIR value was 0.96 for the diagnosis of CR according to the ROC curves and Youden index ( p < 0.001, AUC = 0.9). The condyle-to-cerebral cortex SIR can be used as a noninvasive diagnostic tool for the quantitative evaluation of condylar quality and diagnosis and prognosis of CR. SIR ≥ 0.96 indicates a healthy condyle, while SIR < 0.96 is considered the optimal critical value for the diagnosis of CR. ...
Keywords	temporomandibular joint ; anterior disc displacement ; magnetic resonance imaging ; condylar resorption ; signal intensity ratio ; Medicine ; R
Subject code	610
Language	English
Publishing date	2023-02-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Antibacterial and Anti-Inflammatory Properties of Peptide KN-17

Qian Zhang / Shuipeng Yu / Meilin Hu / Zhiyang Liu / Pei Yu / Changyi Li / Xi Zhang

Microorganisms, Vol 10, Iss 2114, p

2022 Volume 2114

Abstract: Peri-implantitis, an infectious disease originating from dental biofilm that forms around dental implants, which causes the loss of both osseointegration and bone tissue. KN-17, a truncated cecropin B peptide, demonstrated efficacy against certain ... ...

Abstract	Peri-implantitis, an infectious disease originating from dental biofilm that forms around dental implants, which causes the loss of both osseointegration and bone tissue. KN-17, a truncated cecropin B peptide, demonstrated efficacy against certain bacterial strains associated with peri-implantitis. This study aimed to assess the antibacterial and anti-inflammatory properties and mechanisms of KN-17. The effects of KN-17 on oral pathogenic bacteria were assessed by measuring its minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Moreover, the cytotoxicity and anti-inflammatory effects of KN-17 were evaluated. KN-17 inhibited the growth of Streptococcus gordonii and Fusobacterium nucleatum during in vitro biofilm formation and possessed low toxicity to hBMSCs cells. KN-17 also caused RAW264.7 macrophages to transform from M1 to M2 by downregulating pro-inflammatory and upregulating anti-inflammatory factors. It inhibited the NF-κB signaling pathway by reducing IκBα and P65 protein phosphorylation while promoting IκBα degradation and nuclear P65 translocation. KN-17 might be an efficacious prophylaxis against peri-implant inflammation.
Keywords	antibacterial activity ; anti-inflammatory activity ; antimicrobial peptide ; NF-κB signaling pathway ; peri-implantitis ; Biology (General) ; QH301-705.5
Subject code	571
Language	English
Publishing date	2022-10-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: DUS evaluation of nine intersubgeneric hybrids of Paeonia lactiflora and fingerprint analysis of the chemical components in the roots

Shiyi Xu / Weili Liu / Xiubo Liu / Chen Qin / Lianqing He / Panpan Wang / Lingyang Kong / Xi Chen / Zhiyang Liu / Wei Ma

Frontiers in Chemistry, Vol

2023 Volume 11

Abstract: Intersubgeneric hybrids of Paeonia lactiflora (Paeonia lactiflora pall., P. lactiflora.) cover a huge variety of systems in the genus Paeonia. In recent years, many studies have confirmed that the intersubgeneric hybrids of P. lactiflora. are rich in ... ...

Abstract	Intersubgeneric hybrids of Paeonia lactiflora (Paeonia lactiflora pall., P. lactiflora.) cover a huge variety of systems in the genus Paeonia. In recent years, many studies have confirmed that the intersubgeneric hybrids of P. lactiflora. are rich in paeoniflorin and other medicinal ingredients, however, it has always proved difficult to clarify the medicinal value of the hybrids and whether they can be used for medicinal purposes. In this study, the consistency of the plant population was evaluated through DUS evaluation, in order to clarify whether the selected research materials had stability and consistency within the population and specificity between populations. The differences between the paeoniflorin contents in the roots of the nine intersubgeneric hybrids of the P. lactiflora. varieties and two medicinal varieties were critically compared. The differences in the chemical components of the roots of nine intersubgeneric hybrids of P. lactiflora. and reference medicine substances of P. lactiflora. and Paeonia anomala subsp. veitchii (Lynch) D. Y. Hong and K. Y. Pan (Paeonia veitchii Lynch., P. veitchii.) were explored via stoichiometric and chemical fingerprint high performance liquid chromatography analyses. The results showed that there were significant differences in the chemical compositions between the intersubgeneric hybrids of P. lactiflora. and the medicinal reference materials, and the contents of paeoniflorin were elevated such that the hybrids could be used as the raw material for extraction of paeoniflorin, thus providing an opportunity to explore the medicinal value of the hybrids. This study explored the key differential components among the varieties and provides a reference and basis for the study of the medicinal value and the identification of the intersubgeneric hybrids of the P. lactiflora. varieties.
Keywords	Paeonia lactiflora pall ; DUS ; fingerprint analysis ; intersubgeneric hybrid ; paeoniflorin ; stoichiometric analysis ; Chemistry ; QD1-999
Subject code	540
Language	English
Publishing date	2023-03-01T00:00:00Z
Publisher	Frontiers Media S.A.
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Deep Learning-Based Acute Ischemic Stroke Lesion Segmentation Method on Multimodal MR Images Using a Few Fully Labeled Subjects

Bin Zhao / Zhiyang Liu / Guohua Liu / Chen Cao / Song Jin / Hong Wu / Shuxue Ding

Computational and Mathematical Methods in Medicine, Vol

2021 Volume 2021

Abstract: Acute ischemic stroke (AIS) has been a common threat to human health and may lead to severe outcomes without proper and prompt treatment. To precisely diagnose AIS, it is of paramount importance to quantitatively evaluate the AIS lesions. By adopting a ... ...

Abstract	Acute ischemic stroke (AIS) has been a common threat to human health and may lead to severe outcomes without proper and prompt treatment. To precisely diagnose AIS, it is of paramount importance to quantitatively evaluate the AIS lesions. By adopting a convolutional neural network (CNN), many automatic methods for ischemic stroke lesion segmentation on magnetic resonance imaging (MRI) have been proposed. However, most CNN-based methods should be trained on a large amount of fully labeled subjects, and the label annotation is a labor-intensive and time-consuming task. Therefore, in this paper, we propose to use a mixture of many weakly labeled and a few fully labeled subjects to relieve the thirst of fully labeled subjects. In particular, a multifeature map fusion network (MFMF-Network) with two branches is proposed, where hundreds of weakly labeled subjects are used to train the classification branch, and several fully labeled subjects are adopted to tune the segmentation branch. By training on 398 weakly labeled and 5 fully labeled subjects, the proposed method is able to achieve a mean dice coefficient of 0.699±0.128 on a test set with 179 subjects. The lesion-wise and subject-wise metrics are also evaluated, where a lesion-wise F1 score of 0.886 and a subject-wise detection rate of 1 are achieved.
Keywords	Computer applications to medicine. Medical informatics ; R858-859.7
Subject code	006
Language	English
Publishing date	2021-01-01T00:00:00Z
Publisher	Hindawi Limited
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Automatic Acute Ischemic Stroke Lesion Segmentation Using Semi-supervised Learning

Bin Zhao / Shuxue Ding / Hong Wu / Guohua Liu / Chen Cao / Song Jin / Zhiyang Liu

International Journal of Computational Intelligence Systems, Vol 14, Iss

2021 Volume 1

Abstract: Ischemic stroke has been a common disease in the elderly population, which can cause long-term disability and even death. However, the time window for treatment of ischemic stroke in its acute stage is very short. To fast localize and quantitively ... ...

Abstract	Ischemic stroke has been a common disease in the elderly population, which can cause long-term disability and even death. However, the time window for treatment of ischemic stroke in its acute stage is very short. To fast localize and quantitively evaluate the acute ischemic stroke (AIS) lesions, many deep-learning-based lesion segmentation methods have been proposed in the literature, where a deep convolutional neural network (CNN) was trained on hundreds of fully-labeled subjects with accurate annotations of AIS lesions. Such methods, however, require a large number of subjects with pixel-by-pixel labels, making it very time-consuming in data collection and annotation. Therefore, in this paper, we propose to use a large number of weakly-labeled subjects with easy-obtained slice-level labels and a few fully-labeled ones with pixel-level annotations, and propose a semi-supervised learning method. In particular, a double-path classification network (DPC-Net) was proposed and trained using the weakly-labeled subjects to detect the suspicious AIS lesions. A K-means algorithm was used on the diffusion -weighted images (DWIs) to identify the potential AIS lesions due to the a priori knowledge that the AIS lesions appear as hyperintense. Finally, a region-growing algorithm combines the outputs of the DPC-Net and the K-means to obtain the precise lesion segmentation. By using 460 weakly-labeled subjects and 5 fully-labeled subjects to train and fine-tune the proposed method, our proposed method achieves a mean dice coefficient of 0.642, and a lesion-wise F1 score of 0.822 on a clinical dataset with 150 subjects.
Keywords	Semi-supervised learning ; Acute ischemic stroke lesion segmentation ; Convolutional neural network (CNN) ; K-Means ; Region growing ; Electronic computers. Computer science ; QA75.5-76.95
Subject code	006
Language	English
Publishing date	2021-02-01T00:00:00Z
Publisher	Springer
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Group Sparse Precoding for Cloud-RAN with Multiple User Antennas

Zhiyang Liu / Yingxin Zhao / Hong Wu / Shuxue Ding

Entropy, Vol 20, Iss 2, p

2018 Volume 144

Abstract: Cloud radio access network (C-RAN) has become a promising network architecture to support the massive data traffic in the next generation cellular networks. In a C-RAN, a massive number of low-cost remote antenna ports (RAPs) are connected to a single ... ...

Abstract	Cloud radio access network (C-RAN) has become a promising network architecture to support the massive data traffic in the next generation cellular networks. In a C-RAN, a massive number of low-cost remote antenna ports (RAPs) are connected to a single baseband unit (BBU) pool via high-speed low-latency fronthaul links, which enables efficient resource allocation and interference management. As the RAPs are geographically distributed, group sparse beamforming schemes attract extensive studies, where a subset of RAPs is assigned to be active and a high spectral efficiency can be achieved. However, most studies assume that each user is equipped with a single antenna. How to design the group sparse precoder for the multiple antenna users remains little understood, as it requires the joint optimization of the mutual coupling transmit and receive beamformers. This paper formulates an optimal joint RAP selection and precoding design problem in a C-RAN with multiple antennas at each user. Specifically, we assume a fixed transmit power constraint for each RAP, and investigate the optimal tradeoff between the sum rate and the number of active RAPs. Motivated by the compressive sensing theory, this paper formulates the group sparse precoding problem by inducing the ℓ 0 -norm as a penalty and then uses the reweighted ℓ 1 heuristic to find a solution. By adopting the idea of block diagonalization precoding, the problem can be formulated as a convex optimization, and an efficient algorithm is proposed based on its Lagrangian dual. Simulation results verify that our proposed algorithm can achieve almost the same sum rate as that obtained from an exhaustive search.
Keywords	cloud radio access network ; sparse beamforming ; block diagonalization ; group-sparsity ; antenna selection ; Science ; Q ; Astrophysics ; QB460-466 ; Physics ; QC1-999
Subject code	003
Language	English
Publishing date	2018-02-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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