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Vibration response and safety control for blasting vibration of the existing tunnel with defects

Underground Space 2024年第2期15卷 76-89页

作者： Junying Xia Bo Wang xinxin guo Zhuoxiong Xie Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China College of Environment and Civil Engineering Chengdu University of TechnologyChengdu 610059China Guangdong Communication Planning&Design Institute Group Co. LtdGuangzhou 510507China

Current studies on blasting construction of small clear-distance tunnels have not considered the impact of existing tunnel lining defects when establishing safety *** paper offers a series of study results based on the blasting project of a new tunnel adjacent to the existing defect Xinling tunnel to thoroughly examine the dynamic response,safety control standards,and measures of the existing defect ***,structural models were developed to investigate the influence of the presence or absence of specific defects(like lining cracks and cavities behind the lining)on the dynamic response of the current tunnel lining to identify the most unfavorable defect ***,establish safety control standards for intact linings and those with the most unfavorable ***,two types of control measures,single safe charge and reasonable delay time,were studied based on the established safety control *** particular,the most adverse position of cracks was the wall facing the explosion,the rise in depth was more unfavorable for vibration response,and the impact of the longitudinal crack was restricted to the vicinity of the *** the vault was the most adverse cavity position,the rise in cavity area was more damaging,and the influence range varied with longitudinal cavity ***,the impact of cracks was mainly evident in the amplification effect of stress at the crack *** contrast,cavities had varied degrees of amplification effects on the vibration velocity and stress response and a relatively extensive influence *** control research was conducted,when the tunnel was intact,with a right wall crack,a vault cavity,and both vault cavity and crack for this project,the peak particle velocity(PPV)of the safety control standard for vibration velocity was 13,10,13,and 8 cm/s,respectively,and the respective single safe charge could be adjusted at 64,53,37,and 25 ***,the presence of different defects had a relati

关键词： Existing tunnel Defect Blasting construction Vibration response Control standards and measures

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Magnetic micro-particle conditioning–pressurized vertical electro-osmotic dewatering(MPEOD) of activated sludge： Role and behavior of moisture and organics

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Journal of Environmental Sciences 2018年第12期30卷 147-158页

作者： xinxin guo Xu Qian Yili Wang Huaili Zheng College of Environmental Science and Engineering Beijing Key Lab for Source Control Technology of Water Pollution Beijing Forestry University Beijing 100083 China Water Resource Development Research Center of Taihu Basin Authority Shanghai 200434 China Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment State Ministry of Education Chongqing University Chongqing 400045 China

In this study, a magnetic micro-particle conditioning–pressurized vertical electro-osmotic dewatering（MPEOD） process with magnetic micro-particle conditioning–drainage under gravity–mechanical compression–electrical compression（MMPC–DG–MC–EC） stages was established to study the distribution and migration of water, extracellular polymeric substances（EPS）, and other organic matter in the activated sludge（AS） matrix at each *** showed that the MPEOD process could attain 53.52% water content（WC） in dewatered AS with bound water（BW） and free water（FW） reduction rates of 82.97% and 99.67%,respectively. The coagulation and time-delayed magnetic field effects of magnetic microparticles（MMPs） along the MMPC–DG–MC stages initiated the transformation of partial BW to FW in AS. EC had a coupling driving effect of electro-osmosis and pressure on BW, and the changes in pH and temperature at EC stage induced the aggregation of AS flocs and the release of partial BW. Additionally, MMPs dosing further improved the dewatering performance of AS by acting as skeleton builders to provide water passages. Meanwhile, MMPs could disintegrate sludge cells and EPS fractions, thereby reducing tryptophan-like protein and byproduct-like material concentrations in LB-EPS as well as protein/polysaccharide ratio in AS matrix, which could improve AS filterability. At EC stage, the former four Ex/Em regions of fluorescence regional integration analysis for EPS were obviously reduced, especially the protein-like substances in LB-and TB-EPS, which contributed to improvement of AS dewaterability.

关键词： Activated sludge Magnetic micro-particle Pressurized vertical electro-osmotic dewatering Water distribution Extracellular polymeric substance Fluorescence regional integration analysis

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Microwave assisted digestion followed by ICP-MS for determination of trace metals in atmospheric and lake ecosystem

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Journal of Environmental Sciences 2017年第5期29卷 1-10页

作者： Manan Ahmed Ying Hui Chin xinxin guo Xing-Min Zhao Department of Environmental Engineering Faculty of Engineering and Green TechnologyUniversiti Tunku Abdul Rahman College of Resource and Environment Jilin Agriculture University

The study of trace metals in the atmosphere and lake water is important due to their critical effects on humans, aquatic animals and the geochemical balance of ecosystems. The objective of this study was to investigate the concentration of trace metals in atmospheric and lake water samples during the rainy season （before and after precipitation） between November and December 2015. Typical methods of sample preparation for trace metal determination such as cloud point extraction, solid phase extraction and dispersive liquid- liquid micro-extraction are time-consuming and difficult to perform; therefore, there is a crucial need for development of more effective sample preparation procedure. A convection microwave assisted digestion procedure for extraction of trace metals was developed for use prior to inductively couple plasma-mass spectrometric determination. The result showed that metals like zinc （133.50-419.30 μg/m3） and aluminum （53.58-378.93 μg/m3） had higher concentrations in atmospheric samples as compared to lake samples before precipitation. On the other hand, the concentrations of zinc, aluminum, chromium and arsenic were significantly higher in lake samples after precipitation and lower in atmospheric samples. The relationship between physicochemical parameters （pH and turbidity） and heavy metal concentrations was investigated as well. Furthermore, enrichment factor analysis indicated that anthropogenic sources such as soil dust, biomass burning and fuel combustion influenced the metal concentrations in the atmosphere.

关键词： Trace metals Microwave digestion ICP-MS Atmospheric environment Lake ecosystem

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Composition and source apportionment of dust fall around a natural lake

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Journal of Environmental Sciences 2015年第7期27卷 143-155页

作者： Mohd Talib Latif Sofia Aida Ngah Doreena Dominick Intan Suraya Razak xinxin guo Thunwadee Srithawirat Idris Mushrifah School of Environmental and Natural Resource Sciences Faculty of Science and Technology Universiti Kebangsaan Malaysia Institute for Environment and Development (LESTARI) Universiti Kebangsaan Malaysia Centre for Atmospheric Chemistry University of Wollongong Department of Environmental Engineering Faculty of Engineering and Green Technology Universiti Tunku Abdul Rahman Department of Environmental Science Faculty of Science and Technology Pibulsongkram Rajabhat University Pusat Penyelidikan Tasik Chini (PPTC) Faculty of Science and Technology Universiti Kebangsaan Malaysia

The aim of this study was to determine the source apportionment of dust fall around Lake Chini, Malaysia. Samples were collected monthly between December 2012 and March2013 at seven sampling stations located around Lake Chini. The samples were filtered to separate the dissolved and undissolved solids. The ionic compositions（NO-3, SO2-4, Cl-and NH＋4） were determined using ion chromatography（IC） while major elements（K, Na, Ca and Mg） and trace metals（Zn, Fe, Al, Ni, Mn, Cr, Pb and Cd） were determined using inductively coupled plasma mass spectrometry（ICP-MS）. The results showed that the average concentration of total solids around Lake Chini was 93.49 ± 16.16 mg/（m2·day）. SO2-4, Na and Zn dominated the dissolved portion of the dust fall. The enrichment factors（EF） revealed that the source of the trace metals and major elements in the rain water was anthropogenic, except for Fe. Hierarchical agglomerative cluster analysis（HACA） classified the seven monitoring stations and 16 variables into five groups and three groups respectively. A coupled receptor model, principal component analysis multiple linear regression（PCA-MLR）, revealed that the sources of dust fall in Lake Chini were dominated by agricultural and biomass burning（42%）,followed by the earth＇s crust（28%）, sea spray（16%） and a mixture of soil dust and vehicle emissions（14%）.

关键词： Trace metal Major element Anion Source apportionment Lake Ghini Malaysia

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Structural optimization design on the arc receiver array of forward-looking sonar

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Chinese Journal of Acoustics 2023年第1期42卷 40-57页

作者： ZHAO Dongdong LI Fuzeng CHEN Peng MAO Weibo guo xinxin College of Computer Science and Technology Zhejiang University of TechnologyHangzhou 310023 College of Information Engineering Zhejiang University of TechnologyHangzhou 310023 Institute of Deep-sea Science and Engineering Chinese Academy of SciencesSanya 572000

Aiming at the problems that poor isotropic of linear array and limited effective aperture of semicircular array in forward-looking sonar,an optimized structural design method of arc receiving array is *** to different extent of imaging sector,the central angle of arc receiving array is designed to make all elements participate in beamforming of all *** far and near-field focusing model of arc receiving array is established,and the directivity function of arc receiving array is *** radius of arc receiving array with the best beam performance is calculated according to the threshold condition of the boundary beam grating *** comparison of the beam performance at different sector extent of arc array,linear array and semicircular array shows that,the main lobe performance of the arc receiving array is improved by 8%with the view extent between 90°to 130°,and the grating lobe level of the boundary beam is optimized by 4%.The comparison of simulation images with the view extent of 120°and depth of 100 m shows that the cross-directional resolution depth is increased by 20 m and 45 m compared with linear array and semicircular array,the parameter storage capacity is only 2.7%of the linear *** arc array has the advantages of large effective aperture and isotropic beam,which can effectively improve the detection performance of forward-looking sonar system and reduce difficulty of algorithm implementation.

关键词： receiver beam optimization

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A rare case of giant panda cancer:Pancreatic ductal adenocarcinoma

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Animal Models and Experimental Medicine 2022年第6期5卷 582-586页

作者： Yunsheng Wang Maohua Xia Xiangxiang Li xinxin guo Yan Lu Sufen Zhao Tianchun Pu Wildlife Pathological diagnosis Laboratory Department of Veterinary HospitalBeijing ZooBeijingChina Beijing Key Laboratory of Captive Wildlife Technologies Beijing ZooBeijingChina Wildlife Clinical Laboratory Department of Veterinary HospitalBeijing ZooBeijingChina

Pancreatic ductal adenocarcinoma(PDAC)is a highly malignant cancer of the digestive system common among ***,it is rarely reported in wild *** 2018,a giant panda died in the Beijing *** subsequent histological observation of the pancreas,it was discovered that the glandular epithelial cells had lost the pancreatic acinar structure,tubular areas with obvious structure in the pancreas,and the ductal epithelium was substituted by high columnar mucus *** staining showed that there were several fibrous tissue proliferative reactions around the ductal adenocarcinoma and immunohistochemical staining revealed that CK7 and CK19 were positively expressed in the pancreatic ***,the pathological diagnosis indicated that the panda had *** this paper,the panda’s living conditions and pathological diagnosis results are examined,with the aim of providing a reference point for the future diagnosis of wild animal tumors.

关键词： giant panda pancreatic ductal adenocarcinoma(PDAC) the pathological diagnosis of wild animals

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Serum amylase as a novel prognostic marker of organophosphorus poisoning:a retrospective study

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Emergency and Critical Care Medicine 2024年第3期4卷 111-116页

作者： xinxin guo Zhongwei Chen Ke Feng Siyao Zeng Junfei Zhang Zhe Ma Changda Yuan School of Clinical Medicine Ningxia Medical UniversityYinchuanNingxia Hui Autonomous RegionChina Emergency Department General Hospital of Ningxia Medical UniversityYinchuanNingxia Hui Autonomous RegionChina

Background:This study aims to explore the significance of serum amylase levels in patients with organophosphorus pesticide(OP)poisoning and to provide a new perspective for evaluating the severity and prognosis of OP ***:The clinical data of 67 patients with acute OP poisoning,who had been treated in the emergency department of the General Hospital of Ningxia Medical University between September 2020 and August 2022,were retrospectively *** Spearman rank correlation,serum amylase levels during admission and severity of poisoning correlated with discharge *** on serum amylase levels,receiver operating characteristic curves were plotted to predict the severity and mortality of patients who experience organophosphate *** optimal threshold serum amylase level at admission was determined based on the maximum Youden ***:Using Spearman rank correlation analysis,serum amylase levels at admission positively correlated with the severity of poisoning and discharge outcomes,but the degree of correlation was weak(r_(s):0.344;0.264;P194.1 U/L at admission was 15.944(95%CI:1.825-139.274).Conclusion:Serum amylase levels in patients with organophosphate poisoning correlate with the degree of poisoning and discharge *** serum amylase level was a risk factor for organophosphorus poisoning death.

关键词： Amylase Emergency department Organophosphorus pesticide poisoning Prognosis

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BELT AND ROAD INITIATIVE AND GLOBAL GOVERNANCE UNDER PROFOUND CHANGES UNSEEN IN A CENTURY

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Contemporary World 2020年第2期 10-13页

作者： SHI ZHIQIN guo xinxin Department of International Relations Tsinghua University School of Political Science and Public Administration Wuhan University

The Belt and Road Initiative(BRI)was proposed in 2013 by the Chinese President Xi *** to years of effort,the BRI has been enriched whether in theory or in practice,or as an international *** his speeches at a symposium marking the 5th anniversary of the BRI(held in August 2018)and at the Second Belt and Road Forum of International Cooperation(held in April 2019),Xi Jinping gave in-depth elaboration on the dialectic of the BRI and global governance,setting the course for their integration.

关键词： GLOBAL GOVERNANCE UNDER

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A Visual Indoor Localization Method Based on Efficient Image Retrieval

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Journal of Computer and Communications 2024年第2期12卷 47-66页

作者： Mengyan Lyu xinxin guo Kunpeng Zhang Liye Zhang School of Computer Science and Technology Shandong University of Technology Zibo China

The task of indoor visual localization, utilizing camera visual information for user pose calculation, was a core component of Augmented Reality (AR) and Simultaneous Localization and Mapping (SLAM). Existing indoor localization technologies generally used scene-specific 3D representations or were trained on specific datasets, making it challenging to balance accuracy and cost when applied to new scenes. Addressing this issue, this paper proposed a universal indoor visual localization method based on efficient image retrieval. Initially, a Multi-Layer Perceptron (MLP) was employed to aggregate features from intermediate layers of a convolutional neural network, obtaining a global representation of the image. This approach ensured accurate and rapid retrieval of reference images. Subsequently, a new mechanism using Random Sample Consensus (RANSAC) was designed to resolve relative pose ambiguity caused by the essential matrix decomposition based on the five-point method. Finally, the absolute pose of the queried user image was computed, thereby achieving indoor user pose estimation. The proposed indoor localization method was characterized by its simplicity, flexibility, and excellent cross-scene generalization. Experimental results demonstrated a positioning error of 0.09 m and 2.14° on the 7Scenes dataset, and 0.15 m and 6.37° on the 12Scenes dataset. These results convincingly illustrated the outstanding performance of the proposed indoor localization method.

关键词： Visual Indoor Positioning Feature Point Matching Image Retrieval Position Calculation Five-Point Method

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Scalabilities of LEDs and VCSELs with tunnel-regenerated multi-active region structure

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Frontiers of Optoelectronics 2013年第1期6卷 97-101页

作者： Xia guo xinxin LUAN Wenjuan WANG Chunwei guo Guangdi SHEN Photonic Device Research Laboratory (PDRL) Beijing University of Technology Beijing 100124 China

Scalabilities of light-emitting diodes (LEDs) and vertical-cavity surface-emitting lasers (VCSELs) with tunnel-regenerated multi-active-region (TRMAR) structure were investigated. It was found that the output optical power and quantum efficiency of these new LEDs with TRMAR increased with the number of its active regions, but the threshold gain and threshold current density decreased. However, for VCSELs with TRMAR, the differential quantum efficiency and optical power increased with the number of the active region. The results suggest that LEDs and VCSELs with the TRMAR structure have some potential advantages over the conventional LEDs or VCSELs in high internal quantum efficiency, low heat generation, high round-trip gain, and so on. These advantages will make TRMAR LEDs or VCSELs more attractive for the industrial application.

关键词： tunnel junction cascade scalability lightemitting diodes (LEDs) vertical-cavity surface-emitting lasers (VCSELs)

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