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An assessment model of water pipe condition using Bayesian inference

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第7期11卷 495-504页

作者： Chen-wan WANG zhi-guang niu Hui JIA Hong-wei ZHANG School of Environment Science and Technology 27anjin University Tianjin 300072 China School of Environment and Chemical Engineering Tianjin Polytechnic University Tianjin 300160 China

An accurate understanding of the condition of a pipe is important for maintaining acceptable levels of service and providing appropriate strategies for maintenance and rehabilitation in water supply systems. Many factors contribute to pipe deterioration. To consolidate information on these factors to assess the condition of water pipes, this study employed a new ap-proach based on Bayesian configuration against pipe condition to generate factor weights. Ten pipe factors from three pipe ma-terials (cast iron, ductile cast iron and steel) were used in this study. The factors included size, age, inner coating, outer coating, soil condition, bedding condition, trench depth, electrical recharge, the number of road lanes, material, and operational pressure. To address identification problems that arise when switching from pipe factor information to actual pipe condition, informative prior factor weight distribution based on the literature and previous knowledge of water pipe assessment was used. The influence of each factor on the results of pipe assessment was estimated. Results suggested that factors that with smaller weight values or with weights having relative stable posterior means and narrow uncertainty bounds, would have less influence on pipe conditions. The model was the most sensitive to variations of pipe age. Using numerical experiments of different factor combinations, a simplified model, excluding factors such as trench depth, electrical recharge, and the number of road lanes, is provided. The proposed Bayesian inference approach provides a more reliable assessment of pipe deterioration.

关键词： Bayesian inference Condition assessment Pipe factor Water distribution system Weight

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Study on heavy metal concentrations in river sediments through the total amount evaluation method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第5期12卷 399-404页

作者： Chen-chen WANG zhi-guang niu Yan LI Jie SUN Fang WANG School of Environment Science and Technology Tianjin University Tianjin 300072 China Yangtze River Waterway Bureau Encamped in the Binhai Office Tianjin 300072 China Tianjin Urban Construction Design Institute Co. Ltd Tianjin 300072 China

A quantitative method to evaluate the amounts of heavy metals in river sediments is established. Using the BT Drainage River in North China as a study object, six representative cross sections were selected for measurement of heavy metal indicators in sediments, and then the main contamination indicators were determined by performing a potential ecological risk assessment. Using a section of this river as an example, the total amounts of the main pollution indicators and those of their harmful forms are estimated by the Surfer software, which simulates the pollution status within the downstream sediments of the outfall at this section. The calculation results could provide a theoretical guideline and data support for pollution treatment of the BT Drainage River.

关键词： Total amount evaluation Heavy metal pollution River sediments Surfer software

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哈尔滨东部海西期钾长花岗岩的锆石U-Pb年代学及其地质意义

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成都理工大学学报（自然科学版） 2016年第5期43卷 555-563页

作者：牛延宏周志广牛文治王果胜赵孝旗李红英李家亮黑龙江省地质调查研究总院齐齐哈尔分院哈尔滨150036 中国地质大学地球科学与资源学院北京100083

通过对哈尔滨东部地区海西期钾长花岗岩年代学、地球化学特征的研究,讨论兴蒙造山带的演化。研究区钾长花岗岩呈肉红色细粒,主要由钾长石、斜长石、石英和黑云母组成。岩石中SiO_2的质量分数为74.70%~75.70%,为酸性岩。Al_2O_3的质量分... 详细信息

通过对哈尔滨东部地区海西期钾长花岗岩年代学、地球化学特征的研究,讨论兴蒙造山带的演化。研究区钾长花岗岩呈肉红色细粒,主要由钾长石、斜长石、石英和黑云母组成。岩石中SiO_2的质量分数为74.70%~75.70%,为酸性岩。Al_2O_3的质量分数为12.07%~13.18%;Na_2O+K_2O的质量分数为7.78%~8.09%,K_2O/Na_2O为0.93%~1.60%。里特曼指数为1.85~2.06。∑REE的质量分数为96.32×10^(-6)~172.83×10^(-6),δEu为0.21~0.77,为铕负异常;铝饱和指数为0.88~1.12,属于高钾钙碱性花岗岩,与造山带垮塌导致的大规模岩石圈伸展作用有关。该花岗岩LA-ICP-MS锆石U-Pb年龄为(298.54±0.86)Ma(MSWD=0.94),属于晚石炭世,形成于古亚洲洋闭合后兴安地块和松嫩地块碰撞拼合后的伸展作用。

关键词：哈尔滨钾长花岗岩锆石U-Pb年龄海西期地质意义

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C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway as a therapeutic target and regulatory mechanism for spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2231-2244页

作者： Xiangzi Wang Xiaofei niu Yingkai Wang Yang Liu Cheng Yang Xuyi Chen Zhongquan Qi School of Medicine Guangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Graduate School of Tianjin University of Traditional Chinese Medicine TianjinChina Characteristic Medical Center of People’s Armed Police Forces TianjinChina Fujian Maternity and Child Health Hospital FuzhouFujian ProvinceChina

Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory *** expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after *** studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for *** review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord ***,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted ***,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury.

关键词： apoptosis C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway C-C motif chemokine receptor 2 antagonists chemokine ligand 2 chemokine receptor 2 inflammation macrophage microglia spinal cord injury therapeutic method

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Bidirectional regulation of the brain-gut-microbiota axis following traumatic brain injury

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Neural Regeneration Research 2025年第8期20卷 2153-2168页

作者： Xinyu You Lin niu Jiafeng Fu Shining Ge Jiangwei Shi Yanjun Zhang Pengwei Zhuang National Key Laboratory of Chinese Medicine Modernization Tianjin University of Traditional Chinese MedicineTianjinChina Haihe Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjinChina First Teaching Hospital of Tianjin University of Traditional Chinese Medicine TianjinChina National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion TianjinChina

Traumatic brain injury is a prevalent disorder of the central nervous *** addition to primary brain parenchymal damage,the enduring biological consequences of traumatic brain injury pose long-term risks for patients with traumatic brain injury;however,the underlying pathogenesis remains unclear,and effective intervention methods are *** dysfunction is a significant consequence of traumatic brain *** the most densely innervated peripheral tissue in the body,the gut possesses multiple pathways for the establishment of a bidirectional“brain-gut axis”with the central nervous *** gut harbors a vast microbial community,and alterations of the gut niche contribute to the progression of traumatic brain injury and its unfavorable prognosis through neuronal,hormonal,and immune pathways.A comprehensive understanding of microbiota-mediated peripheral neuroimmunomodulation mechanisms is needed to enhance treatment strategies for traumatic brain injury and its associated *** comprehensively reviewed alterations in the gut microecological environment following traumatic brain injury,with a specific focus on the complex biological processes of peripheral nerves,immunity,and microbes triggered by traumatic brain injury,encompassing autonomic dysfunction,neuroendocrine disturbances,peripheral immunosuppression,increased intestinal barrier permeability,compromised responses of sensory nerves to microorganisms,and potential effector nuclei in the central nervous system influenced by gut ***,we reviewed the mechanisms underlying secondary biological injury and the dynamic pathological responses that occur following injury to enhance our current understanding of how peripheral pathways impact the outcome of patients with traumatic brain *** review aimed to propose a conceptual model for future risk assessment of central nervous system-related diseases while elucidating novel insights into the bidirectional effec

关键词： traumatic brain injury brain-gut-microbiome axis gut microbiota neuroimmune immunosuppression host defense vagal afferents bacterial infection dorsal root ganglia nociception neural circuitry

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Liposomes as versatile agents for the management of traumatic and nontraumatic central nervous system disorders:drug stability,targeting efficiency,and safety

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Neural Regeneration Research 2025年第7期20卷 1883-1899页

作者： Mingyu Zhang Chunyu Xiang Renrui niu Xiaodong He Wenqi Luo Wanguo Liu Rui Gu Department of Orthopedic Surgery China-Japan Union Hospital of Jilin UniversityChangchunJilin ProvinceChina

Various nanoparticle-based drug delivery systems for the treatment of neurological disorders have been widely ***,their inability to cross the blood–brain barrier hampers the clinical translation of these therapeutic *** are nanoparticles composed of lipid bilayers,which can effectively encapsulate drugs and improve drug delivery across the blood–brain barrier and into brain tissue through their targeting and ***,they can potentially treat traumatic and nontraumatic central nervous system *** this review,we outlined the common properties and preparation methods of liposomes,including thin-film hydration,reverse-phase evaporation,solvent injection techniques,detergent removal methods,and microfluidics ***,we comprehensively discussed the current applications of liposomes in central nervous system diseases,such as Alzheimer's disease,Parkinson's disease,Huntington's disease,amyotrophic lateral sclerosis,traumatic brain injury,spinal cord injury,and brain *** studies related to liposomes are still in the laboratory stage and have not yet entered clinical ***,their application as drug delivery systems in clinical practice faces challenges such as drug stability,targeting efficiency,and ***,we proposed development strategies related to liposomes to further promote their development in neurological disease research.

关键词： Alzheimer's disease amyotrophic lateral sclerosis brain tumors central nervous system Huntington's disease liposome drug delivery neurological disorders Parkinson's disease spinal cord injury traumatic brain injury

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Multiphysics simulation and optimization of the in-situ beneficiation process of ilmenite minerals from lunar regolith

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Science China Earth Sciences 2025年第1期 195-207页

作者： Peng ZHANG Xin LIU guanghui LIU Wei DAI Hanzhe YANG Haibo ZHENG zhi WANG Ran niu Yifan BAI Yang ZHANG Chengbao LIU Ge YANG Junwei YANG guang ZHANG Technology and Engineering Center for Space Utilization Chinese Academy of Sciences Beijing Hegong Simulation Co. Ltd

The exploration and utilization of lunar resources have become the major objectives of future lunar exploration missions. The classified collection and processing of lunar minerals is the basic prerequisite for the in-situ exploration and utilization of lunar resources. In this study, we propose a scheme for in-situ separation of magnetic minerals from lunar soils using the dry magnetic separation method. The scheme can realize the purpose of separating magnetic minerals from lunar regolith by altering the motion trajectory of lunar regolith particles with different magnetic properties. Detailed modeling of the dry magnetic separation device is conducted, and the three-dimensional distribution of magnetic parameters is calculated and analyzed. Based on the characterization and analysis of the Chang E-5's samples, the morphologies and physical parameters of lunar regolith particles are modeled and simulated. A discrete element simulation of the motion process of lunar regolith particles under multi-physical field conditions is performed, and the influences of key parameters on the beneficiation performance of lunar magnetic minerals are investigated. Our results indicate that optimal separation and beneficiation of lunar regolith particles can be achieved under specific conditions of magnetic field strength and drum speed. Additionally, we analyze the effects of lunar weak gravity conditions and the charged nature of lunar particles on the beneficiation process, showing that these factors can obviously enhance the beneficiation process of lunar ilmenites. This study demonstrates the feasibility of using the dry magnetic separation method for the beneficiation of magnetic minerals from lunar regolith, providing a theoretical basis for the scientific tasks of collecting, processing, and utilizing lunar mineral resources.

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JPEG stream soft-decoding technique based on autoregressive modeling

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The Journal of China Universities of Posts and Telecommunications 2012年第5期19卷 115-123页

作者： niu Yi SHI guang-ming WANG Xiao-tian WANG Li-zhi GAO Da-hua School of Electronic Engineering Xidian University Xi'an 710071 China ECE McMaster University Hamilton L8S 4KI Canada School of Science Air Force Engineering University Xi'an 710051 China

This paper introduces a new model-based soft decoding techniqt, e to restore the widely used joint photographic expert group （JPEG） streams. The image is modeled as a two dimensional （2D） piecewise stationary autoregressive process, and the decoding task is formulated as a constrained optimization problem. All the constraints are given by the quantization intervals which available at the decoder freely. The autoregressive model serves as an important regularization term of the objective function of the optimization, and the model parameters are solved on the decoded image locally using a weighted total least square method. In addition, a novel bilateral dualside weighting scheme is proposed to minimize the influence of the blocking artifact on the accuracy of parameter estimation. Extensive experimental results suggest that the proposed algorithm systematically improves the quality of JPEG images and also outperforms existing JPEG postprocessing algorithms in a wide bit-rate range both in terms of peak signal-to-noise ratio （PSNR） and subjective quality

关键词： image deblocking autoregressive modeling constrained optimization total least squares bilateral weighting

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Models to predict sunlight-induced photodegradation rates of contaminants in wastewater stabilisation ponds and clarifiers

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Water Science and Engineering 2019年第4期12卷 293-297页

作者： Xi-zhi niu Department of Chemical and Environmental Engineering and Arizona Laboratory for Emerging Contaminants University of Arizona

Two kinetic models were established for conservative estimates of photodegradation rates of contaminants under sunlight irradiation,in particular for wastewater stabilisation ponds and clarifiers in conventional wastewater treatment *** two models were designated for(1)contaminants with high photolytic rates or high photolytic quantum yields,whose photodegradation is unlikely to be enhanced by aquatic photosensitisers;and(2)contaminants withstanding direct photolysis in sunlit waters but subjected to indirect *** effortlessly intelligible prediction procedure involves sampling and analysis of real water samples,simulated solar experiments in the laboratory,and transfer of the laboratory results to realise water treatment using the prediction *** similar models have been widely used for laboratory studies,this paper provides a preliminary example of translating laboratory results to the photochemical fate of contaminants in real waters.

关键词： Sunlight irradiation Photodegradation Contaminants Stabilisation ponds Solar water treatment

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Phase noise sensitivity analysis of lattice constellation

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The Journal of China Universities of Posts and Telecommunications 2010年第2期17卷 36-40页

作者： YU guang-wei niu Kai HE zhi-qiang WANG Xu-zhen LIN Jia-ru Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Based on the assumption of large number of constellation points and high signal-to-noise ratio （SNR）, phase noise sensitivity of lattice constellation is analyzed. The upper bound of symbol error rate （SER） in additive white Gaussian noise （AWGN） channel is derived from pairwise error probability. For small phase noise, phase noise channel is transformed to AWGN channel. With the aid of Wiener model, the obtained upper bound can be extended to phase noise channel. The proposed upper bound can be used as performance criterion to analyze the sensitivity of phase noise in multi-dimensional lattice constellation. Simulation results show that with the same normalized spectral efficiency, higher dimensional lattice constellations are more sensitive than lower ones in phase noise channel. It is also shown that with the same dimension of constellation, larger normalized spectral efficiency means more performance loss in phase noise channel.

关键词： lattice constellation symbol error rate (SER) phase noise

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