Performance monitoring of timber structures in underground construction using wireless SmartPlank

Xu, Xiaomin,Soga, Kenichi,Nawaz, Sarfraz,Moss, Neil,Bowers, Keith,Gajia, Mohammed Techno-Press 2015 Smart Structures and Systems, An International Jou Vol.15 No.3

Although timber structures have been extensively used in underground temporary supporting system, their actual performance is poorly understood, resulting in potentially conservative and over-engineered design. In this paper, a novel wireless sensor technology, SmartPlank, is introduced to monitor the field performance of timber structures during underground construction. It consists of a wooden beam equipped with a streamlined wireless sensor node, two thin foil strain gauges and two temperature sensors, which enables to measure the strain and temperature at two sides of the beam, and to transmit this information in real-time over an IPv6 (6LowPan) multi-hop wireless mesh network and Internet. Four SmartPlanks were deployed at the London Underground's Tottenham Court Road (TCR) station redevelopment site during the Stair 14 excavation, together with seven relay nodes and a gateway. The monitoring started from August 2013, and will last for one and a half years until the Central Line possession in 2015. This paper reports both the short-term and long-term performances of the monitored timber structures. The grouting effect on the short-term performance of timber structures is highlighted; the grout injection process creates a large downward pressure on the top surface of the SmartPlank. The short and long term earth pressures applied to the monitored structures are estimated from the measured strains, and the estimated values are compared to the design loads.

Performance monitoring of timber structures in underground construction using wireless SmartPlank

Xiaomin Xu,Kenichi Soga,Sarfraz Nawaz,Neil Moss,Keith Bowers,Mohammed Gajia 국제구조공학회 2015 Smart Structures and Systems, An International Jou Vol.15 No.3

Although timber structures have been extensively used in underground temporary supportingsystem, their actual performance is poorly understood, resulting in potentially conservative andover-engineered design. In this paper, a novel wireless sensor technology, SmartPlank, is introduced tomonitor the field performance of timber structures during underground construction. It consists of a woodenbeam equipped with a streamlined wireless sensor node, two thin foil strain gauges and two temperaturesensors, which enables to measure the strain and temperature at two sides of the beam, and to transmit thisinformation in real-time over an IPv6 (6LowPan) multi-hop wireless mesh network and Internet. FourSmartPlanks were deployed at the London Underground’s Tottenham Court Road (TCR) stationredevelopment site during the Stair 14 excavation, together with seven relay nodes and a gateway. Themonitoring started from August 2013, and will last for one and a half years until the Central Line possessionin 2015. This paper reports both the short-term and long-term performances of the monitored timberstructures. The grouting effect on the short-term performance of timber structures is highlighted; the groutinjection process creates a large downward pressure on the top surface of the SmartPlank. The short and longterm earth pressures applied to the monitored structures are estimated from the measured strains, and theestimated values are compared to the design loads.

Dynamic and motion consistency analysis for a planar parallel mechanism with revolute dry clearance joints

Bicai Xu,Xupeng Wang,Xiaomin Ji,Ruiting Tong,Yanmin Xue 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.7

The aim of the research was to introduce a methodology for dynamic response and motion consistency research on multibody system with multiple revolute clearance joints. An improved impact force model and a modified friction force model were introduced to evaluate the effects of impact and friction in clearance joints. A planar parallel mechanism which has two clearance joints in the left wing and the right wing was also used as an example. From the results based on different conditions, clearance has slight influence on the angular displacement and angular velocity, but obvious effect on angular acceleration. And with same clearance values of left wing and right wing, the motion consistency of the parallel mechanism is very good, which means the dynamic response of two wings is almost symmetrical. When the two clearance joints have different clearance values, the motion consistency and relative error between two wings are much obvious, especially the angular acceleration.

Adaptive low-resolution palmprint image recognition based on channel attention mechanism and modified deep residual network

Xuebin Xu,Kan Meng,Xiaomin Xing,Chen Chen 한국인터넷정보학회 2022 KSII Transactions on Internet and Information Syst Vol.16 No.3

Palmprint recognition has drawn increasingly attentions in the past decade due to its uniqueness and reliability. Traditional palmprint recognition methods usually use high-resolution images as the identification basis so that they can achieve relatively high precision. However, high-resolution images mean more computation cost in the recognition process, which usually cannot be guaranteed in mobile computing. Therefore, this paper proposes an improved low-resolution palmprint image recognition method based on residual networks. The main contributions include: 1) We introduce a channel attention mechanism to refactor the extracted feature maps, which can pay more attention to the informative feature maps and suppress the useless ones. 2) The ResStage group structure proposed by us divides the original residual block into three stages, and we stabilize the signal characteristics before each stage by means of BN normalization operation to enhance the feature channel. Comparison experiments are conducted on a public dataset provided by the Hong Kong Polytechnic University. Experimental results show that the proposed method achieve a rank-1 accuracy of 98.17% when tested on low-resolution images with the size of 12dpi, which outperforms all the compared methods obviously.

The stability and removal of water-dispersed CdSe/CdS core-shell quantum dots from water

Chen, Xu,Ok, Yong Sik,Mohan, Dinesh,Pittman Jr., Charles U.,Dou Jr., Xiaomin Elsevier 2017 CHEMOSPHERE - Vol.185 No.-

<P><B>Abstract</B></P> <P>The increasingly wide use of semiconductor nanocrystals inevitably leads to their release into aquatic environment. The aggregation behaviors of 3-mercaptopropionic acid-capped CdSe/CdS core-shell quantum dots (MPA-QDs) under various water chemistry conditions were examined and their removal using Fe<SUP>3+</SUP> and Al<SUP>3+</SUP> coagulants was evaluated. Cationic species rather than concentrations affected the stability of MPA-QDs. Adding 2 mM Ca<SUP>2+</SUP> led to a much larger ζ-potential decrease and particle size increase than adding 150 mM K<SUP>+</SUP> at each tested solution pH. This indicated that complexation and depletion of surface-bound carboxyl groups by divalent Ca<SUP>2+</SUP> has a more pronounced effect than compression of the electrical double layer by high concentrations of monovalent K<SUP>+</SUP>. The presence of humic acid increased the stability of MPA-QDs, which might increase negative surface charging <I>via</I> overcoating or bind to the surface of MPA-QDs. The nanoparticles exhibited similar aggregation kinetics patterns in tap water and seawater, but varying patterns in the lake water because of the co-existence of 2.3 mM total of Ca<SUP>2+</SUP> and Mg<SUP>2+</SUP>. MPA-QDs (5 mg L<SUP>−1</SUP>) were readily coagulated by 2.4 mM Al<SUP>3+</SUP> or 1.2 mM Fe<SUP>3+</SUP> in tap water. Al<SUP>3+</SUP> and Fe<SUP>3+</SUP> can bind with carboxyl groups of the surface capping ligands, neutralize the negative charges on the surface of MPA-QDs and decrease the electrostatic repulsion forces to induce MPA-QDs aggregation. In addition, MPA-QDs could be bound with and wrapped into the flocs of hydrolysis products of coagulants. The results reported here could help broaden our understanding of the impacts and remediation of water-dispersed core-shell QD nanoparticles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The stability, aggregation and remediation of core/shell QDs were evaluated. </LI> <LI> Ca<SUP>2+</SUP> led to severe aggregation of soluble QDs than K<SUP>+</SUP> at much lower concentrations. </LI> <LI> Depletion of surface bound ligand has a more pronounced effect than compression EDL. </LI> <LI> QDs exhibited different aggregation patterns in tap water, seawater and lake water. </LI> <LI> Both Fe<SUP>3+</SUP> and Al<SUP>3+</SUP> were able to remediate QDs from water but the former was better. </LI> </UL> </P>

Boosting the oxygen evolution reaction activity of a perovskite through introducing multi-element synergy and building an ordered structure

Sun, Hainan,Xu, Xiaomin,Hu, Zhiwei,Tjeng, Liu Hao,Zhao, Jie,Zhang, Qin,Lin, Hong-Ji,Chen, Chien-Te,Chan, Ting-Shan,Zhou, Wei,Shao, Zongping The Royal Society of Chemistry 2019 Journal of Materials Chemistry A Vol.7 No.16

<P>If different active sites in a catalyst have optimal binding to different reaction intermediates and short reaction paths among them, they may work cooperatively to enhance the oxygen evolution reaction (OER) activity. Based on this design principle, in this study, we start with a B-site ordered double perovskite Sr2FeMoO6−δ with poor OER activity as the host material to fulfill the requirement of a short pathway, and then, replace Mo with Ni and Fe with Co to optimize the synergistic interplay of the multi-active sites. Replacing Mo with Ni indeed dramatically enhances the OER activity and structural/operating stability. Further improvement in OER performance is realized by partial substitution of Fe with Co, leading to the development of a material with the nominal composition of Sr2Fe0.8Co0.2Mo0.65Ni0.35O6−δ, which outperforms the noble metal oxide IrO2 and is better than most of the electrocatalysts developed based on a single descriptor, such as Ba0.5Sr0.5Co0.8Fe0.2O3−δ (eg occupancy close to unity), PrBaCo2O5+δ (O 2p-band center relative to the Fermi level), and La0.5Sr0.5CoO3−δ (charge-transfer energy) in many aspects. As a universal method, combined structural and compositional tuning to create a cooperative effect among different active sites for intermediate adsorption and reaction in an ordered structure may provide a new way for the design of superior electrocatalysts for various applications.</P>

Isoforms of wild type proteins often appear as low molecular weight bands on SDS-PAGE.

Zhang, Ju,Lou, Xiaomin,Shen, Haihong,Zellmer, Lucas,Sun, Yuan,Liu, Siqi,Xu, Ningzhi,Liao, D Joshua Wiley 2014 Biotechnology Journal Vol.9 No.8

<P>Immunoblotting, after polyacrylamide gel electrophoresis with sodium dodecyl sulfate (SDS-PAGE), is a technique commonly used to detect specific proteins. SDS-PAGE often results in the visualization of protein band(s) in addition to the one expected based on the theoretical molecular mass (TMM) of the protein of interest. To determine the likelihood of additional band(s) being nonspecific, we used liquid chromatography - mass spectrometry to identify proteins that were extracted from bands with the apparent molecular mass (MM) of 40 and 26 kD, originating from protein extracts derived from non-malignant HEK293 and cancerous MDA-MB231 (MB231) cells separated using SDS-PAGE. In total, approximately 57% and 21% of the MS/MS spectra were annotated as peptides in the two cell samples, respectively. Moreover, approximately 24% and 36.2% of the identified proteins from HEK293 and MB231 cells matched their TMMs. Of the identified proteins, 8% from HEK293 and 26% from MB231 had apparent MMs that were larger than predicted, and 67% from HEK293 and 37% from MB231 exhibited smaller MM values than predicted. These revelations suggest that interpretation of the positive bands of immunoblots should be conducted with caution. This study also shows that protein identification performed by mass spectrometry on bands excised from SDS-PAGE gels could make valuable contributions to the identification of cancer biomarkers, and to cancer-therapy studies.</P>

Recovery of ammonium and phosphate from source-separated urine using the decomposition product of struvite pellet by microwave radiation

Shihua CHEN,Min ZHENG,Xiaomin DOU,Kangning XU 대한환경공학회 2019 대한환경공학회 학술발표논문집 Vol.2019 No.-

Ternary Phase Diagram-Facilitated Rapid Screening of Double Perovskites As Electrocatalysts for the Oxygen Evolution Reaction

Sun, Hainan,Hu, Zhiwei,Xu, Xiaomin,He, Juan,Dai, Jie,Lin, Hong-Ji,Chan, Ting-Shan,Chen, Chien-Te,Tjeng, Liu Hao,Zhou, Wei,Shao, Zongping American Chemical Society 2019 Chemistry of materials Vol.31 No.15

<P>The development of cost-effective, non-noble metal electrocatalysts for the oxygen evolution reaction (OER) is of paramount importance for sustainable technologies. Efficient screening strategies for electrocatalysts can greatly increase the commercialization speed of these advanced technologies. Here, ternary phase diagrams with large-scale tuning and designated-scale tuning strategies are applied for the first time to provide a new method for screening perovskite oxide-based electrocatalysts for OERs. Specifically, the family of double perovskites (Sr<SUB>2</SUB>Fe<SUB>1.5-<I>x</I>-<I>y</I></SUB>Co<SUB><I>x</I></SUB>Ni<SUB><I>y</I></SUB>Mo<SUB>0.5</SUB>O<SUB>6−δ</SUB>, 0 ≤ <I>x</I>, <I>y</I> ≤ 1.5) was utilized to understand the role of transition metals in perovskite oxides. Ternary phase diagrams can facilitate a rapid screening process, provide a straightforward relationship between phase structures and catalytic activities, and help to confirm the effects of various combinations of transition metals on the OER activity. The Fe-Co system (Sr<SUB>2</SUB>Fe<SUB>1.5-<I>x</I></SUB>Co<SUB><I>x</I></SUB>Mo<SUB>0.5</SUB>O<SUB>6−δ</SUB>) improves the catalytic activities, as demonstrated by the reduced Tafel slope and enhanced stability, while the Fe-Ni system (Sr<SUB>2</SUB>Fe<SUB>1.5-<I>y</I></SUB>Ni<SUB><I>y</I></SUB>Mo<SUB>0.5</SUB>O<SUB>6−δ</SUB>) improves the surface kinetic properties of the OER, as demonstrated by its reduced overpotential. Significantly, the Co, Ni, and Fe ternary phase systems can serve as the synergistic coactive sites (Sr<SUB>2</SUB>Fe<SUB>1.5-<I>x</I>-<I>y</I></SUB>Co<SUB><I>x</I></SUB>Ni<SUB><I>y</I></SUB>Mo<SUB>0.5</SUB>O<SUB>6−δ</SUB>) to catalyze the OER, resulting in an improved overall OER performance. This systematic study not only demonstrates a new strategy to allow the rapid screening of double perovskite OER catalysts based on large-scale tuning and designated-scale tuning strategies but, more importantly, also provides an insightful understanding of the use of multitransition metal-based double perovskites for catalysis of the OER.</P> [FIG OMISSION]</BR>

MicroRNA-145-5p Regulates the Epithelial-Mesenchymal Transition in Nasal Polyps by Targeting Smad3

Mengyu Zhang,Manyi Li,Xiaomin Lu,Xiaole Peng,Xiaolong Liang,Wentao Wang,Yuqing Yang,Fan Xu,Dechun Geng 대한이비인후과학회 2024 Clinical and Experimental Otorhinolaryngology Vol.17 No.2

Objectives. The annual prevalence of chronic rhinosinusitis (CRS) is increasing, and the lack of effective treatments imposesa substantial burden on both patients and society. The formation of nasal polyps in patients with CRS is closely relat-ed to tissue remodeling, which is largely driven by the epithelial-mesenchymal transition (EMT). MicroRNA (miRNA)plays a pivotal role in the pathogenesis of numerous diseases through the miRNA-mRNA regulatory network; how-ever, the specific mechanism of the miRNAs involved in the formation of nasal polyps remains unclear. Methods. The expression of EMT markers and Smad3 were detected using western blots, quantitative real-time polymerasechain reaction, and immunohistochemical and immunofluorescence staining. Differentially expressed genes in nasalpolyps and normal tissues were screened through the Gene Expression Omnibus database. To predict the target genesof miR-145-5p, three different miRNA target prediction databases were used. The migratory ability of cells was evalu-ated using cell migration assay and wound healing assays. Results. miR-145-5p was associated with the EMT process and was significantly downregulated in nasal polyp tissues. Invitro experiments revealed that the downregulation of miR-145-5p promoted EMT. Conversely, increasing miR-145-5p levels reversed the EMT induced by transforming growth factor-β1. Bioinformatics analysis suggested that miR-145-5p targets Smad3. Subsequent experiments confirmed that miR-145-5p inhibits Smad3 expression. Conclusion. Overall, miR-145-5p is a promising target to inhibit nasal polyp formation, and the findings of this study pro-vide a theoretical basis for nanoparticle-mediated miR-145-5p delivery for the treatment of nasal polyps.