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On the Downshift of Wave Frequency for Bragg Resonance

China Ocean Engineering 2022年第1期36卷 76-85页

作者： PENG Ji TAO Ai-feng FAN Jun ZHENG Jin-hai liu yu-ming Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing 210098China Quality Supervision Department China Renewable Energy Engineering InstituteBeijing 100120China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridge 02139USA

For surface gravity waves propagating over a horizontal bottom that consists of a patch of sinusoidal ripples,strong wave reflection occurs under the Bragg resonance condition.The critical wave frequency,at which the peak reflection coefficient is obtained,has been observed in both physical experiments and direct numerical simulations to be downshifted from the well-known theoretical prediction.It has long been speculated that the downshift may be attributed to higher-order rippled bottom and free-surface boundary effects,but the intrinsic mechanism remains unclear.By a regular perturbation analysis,we derive the theoretical solution of frequency downshift due to third-order nonlinear effects of both bottom and free-surface boundaries.It is found that the bottom nonlinearity plays the dominant role in frequency downshift while the free-surface nonlinearity actually causes frequency upshift.The frequency downshift/upshift has a quadratic dependence in the bottom/free-surface steepness.Polychromatic bottom leads to a larger frequency downshift relative to the monochromatic bottom.In addition,direct numerical simulations based on the high-order spectral method are conducted to validate the present theory.The theoretical solution of frequency downshift compares well with the numerical simulations and available experimental data.

关键词： gravity surface wave Bragg resonance frequency downshift regular perturbation analysis

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猪肉理化指标的近红外光谱无损检测

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光谱学与光谱分析 2024年第5期44卷 1346-1353页

作者：刘瑜明王巧华陈远哲刘成康范维祝志慧刘世伟华中农业大学工学院湖北武汉430070 华中农业大学深圳营养与健康研究院湖北武汉430070 中国农业科学院深圳农业基因组研究所和岭南现代农业科学与技术广东省实验室深圳分中心广东深圳518124

我国是世界上最大的猪肉生产国,同时也是最大的消费国。猪肉的品质影响着人们摄取蛋白质的质量,目前缺乏有效的快速无损检测方法应对巨大的检测需要。为快速测定冷藏猪肉挥发性盐基氮(TVB-N)、pH值和含水率,提出一种新的猪肉品质检测方... 详细信息

我国是世界上最大的猪肉生产国,同时也是最大的消费国。猪肉的品质影响着人们摄取蛋白质的质量,目前缺乏有效的快速无损检测方法应对巨大的检测需要。为快速测定冷藏猪肉挥发性盐基氮(TVB-N)、pH值和含水率,提出一种新的猪肉品质检测方法,利用近红外光谱技术结合化学计量学方法建立冷藏猪肉TVB-N、pH值和含水率的数学模型。以不同种类的白条猪肉为研究对象,选择排酸完成后的猪最长背部肌肉的切块,采集相应猪肉近红外光谱数据并结合化学计量学试验获取TVB-N、pH和含水率的测量值,对比分析采集到的光谱信息和理化指标,发现在8600~8450、7160~6950、5300~5000 cm^(-1)区域出现显著的吸收峰,而8600~8450 cm^(-1)附近吸收峰的峰值却明显小于其他吸收峰。使用SPXY(sample set partitioning based on joint X-Y distances)算法进行数据集划分,将数据集按照3∶1的比例划分成训练集和测试集。使用蒙特卡罗交叉验证法(MCCV)剔除异常数据,通过偏最小二乘法回归(PLSR)建立TVB-N、pH值、含水率和全波段光谱信息的回归关系。利用数据中心化、Savitzky-Golay(S-G)一阶求导、S-G二阶求导、直接差分二阶求导和多元散射校正等方法对原始光谱进行预处理,探寻合适的预处理方式。结果显示:数据中心化、直接差分二阶求导、二阶求导取得较优的试验效果;故结合竞争性自适应重加权算法(CARS)、非信息变量剔除(UVE)、连续投影算法(SPA)等特征波长提取算法建立PLSR特征波段模型并进行分析。结果显示,TVB-N、pH值、含水率的预测模型结构分别为数据中心化-CARS-PLSR、直接差分二阶求导-CARS-PLSR、二阶求导-CARS-PLSR时具有优异的性能,其中训练集相关系数RC分别为0.9471、0.9988、0.9971,均方根误差(RMSE)分别为1.2088、0.0087、0.0015;测试集相关系数RP分别为0.9275、0.9630、0.9459,RMSE分别为1.6836、0.0517、0.0056。综上可知,近红外波段区域与猪肉TVB-N、pH值、含水率存在显著相关性,利用近红外光谱可以准确预测猪肉中TVB-N、pH值和含水率。

关键词：猪肉近红外光谱 TVB-N pH 含水率

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Rough Set Theory Based Approach for Fault Diagnosis Rule Extraction of Distribution System

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高电压技术 2008年第12期34卷 2713-2718页

作者： ZHOU Yong-yong ZHOU Quan liu Jia-bin liu yu-ming REN Hai-jun SUN Cai-xin liu Xu State Key Laboratory of Power Transmission Equipment & SyStem Security and New Technology Chongqing University Chongqing 400044 China Qinan Power Supply Bureau Chongqing 400800 China Dazhou Power Corporation Dazhou 635000 China

As the first step of service restoration of distribution system,rapid fault diagnosis is a significant task for reducing power outage time,decreasing outage loss,and subsequently improving service reliability and safety.This paper analyzes a fault diagnosis approach by using rough set theory in which how to reduce decision table of data set is a main calculation intensive task.Aiming at this reduction problem,a heuristic reduction algorithm based on attribution length and frequency is proposed.At the same time,the corresponding value reduction method is proposed in order to fulfill the reduction and diagnosis rules extraction.Meanwhile,a Euclid matching method is introduced to solve confliction problems among the extracted rules when some information is lacking.Principal of the whole algorithm is clear and diagnostic rules distilled from the reduction are concise.Moreover,it needs less calculation towards specific discernibility matrix,and thus avoids the corresponding NP hard problem.The whole process is realized by MATLAB programming.A simulation example shows that the method has a fast calculation speed,and the extracted rules can reflect the characteristic of fault with a concise form.The rule database,formed by different reduction of decision table,can diagnose single fault and multi-faults efficiently,and give satisfied results even when the existed information is incomplete.The proposed method has good error-tolerate capability and the potential for on-line fault diagnosis.

关键词：粗糙集理论配电网故障诊断提取方法规则匹配

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环境地质信息系统支持下的城市水文风险评估与管理

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智能建筑与智慧城市 2024年第2期 43-45页

作者：汤江平严军刘玉明湖北省地质局第八地质大队

文章详细论述了环境地质信息系统的体系架构、数据组织以及功能模块,立足环境地质信息系统,分析了其在城市水文风险评估与管理中的应用,从海量、动态、多元的环境地质数据支持,到GIS空间分析方法、数据挖掘算法、人工智能算法等城市水... 详细信息

文章详细论述了环境地质信息系统的体系架构、数据组织以及功能模块,立足环境地质信息系统,分析了其在城市水文风险评估与管理中的应用,从海量、动态、多元的环境地质数据支持,到GIS空间分析方法、数据挖掘算法、人工智能算法等城市水文风险评估方法支持等方面详细论述了城市水文风险评价、分级、管理的应用场景,助力城市水文灾害预测、风险管控、应急管理。

关键词：环境地质信息系统城市水文风险评估 GIS技术

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Erratum to:On the Downshift of Wave Frequency for Bragg Resonance[China Ocean Engineering,2022,36(1),76-85.https://***/10.1007/s13344-022-0006-y]

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China Ocean Engineering 2022年第2期36卷 332-332页

In the original publication of the article(Peng et al.2022),under the section‘Comparisons with experiments and direct numerical simulations’,Fig.4 was not included.The figure is given below:Reference Peng,J.,Tao.,A.F.,Fan,J.,Zheng,J.H.and liu,Y.M.,2022.On the downshift of wave frequency for Bragg resonance,China Ocean Engineering,36(1),76-85.

关键词： Wave wave

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The Establishment of SWAT Database in Guishui River Basin,Beijing,China

The Establishment of SWAT Database in Guishui River Basin,Be...

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2011 International Symposium on Water Resource and Environmental Protection(ISWREP 2011)

作者： liu yu-ming ZHANG Jing Key Lab of Three Dimension Information Acquisition Application Capital Normal University

SWAT model is a long-term distributed hydrologic model which can simulate basins well in China.But its original database is designed for US while it is not fit for China in the research.It has been restricting its development in China.In this paper,the method of establishing a database in Guishui River basin was focused on.Moreover,precipitation interpolation and the conversion of soil and landuse data are discussed.Finally,the calculation of the key data and parameters is presented,like solar radiation data and user weather station parameters.

关键词： SWAT model database precipitation interpolation parameter calculation

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竹山县文峪河流域硫铁矿区不稳定斜坡稳定性分析

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工程建设与设计 2024年第2期 41-43页

作者：汤江平刘玉明曹云健湖北省地质局第八地质大队湖北襄阳441000

竹山县文峪河流域硫铁矿区地质灾害防治工程勘查中,通过对矿区不良地质作用隐患的发育类型、特征进行分析,查明了矿区地质环境条件、地质灾害特征,获取了岩土层物理力学参数,对灾害形成机理及变形影响因素进行分析,对不稳定斜坡体进行... 详细信息

竹山县文峪河流域硫铁矿区地质灾害防治工程勘查中,通过对矿区不良地质作用隐患的发育类型、特征进行分析,查明了矿区地质环境条件、地质灾害特征,获取了岩土层物理力学参数,对灾害形成机理及变形影响因素进行分析,对不稳定斜坡体进行分析评价,为工程治理设计提供了基础数据和防治方案建议,确保了矿区防治工程总体可实施性和安全性。

关键词：地质灾害勘查不稳定斜坡稳定性分析

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Mesenchymal stem cells for repairing glaucomatous optic nerve

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 748-760页

作者： Bai-yu Hu Mei Xin ming Chen Ping yu liu-Zhi Zeng Eye School of Chengdu University of TCM Chengdu 610000Sichuan ProvinceChina Department of Ophthalmology Chengdu First People’s HospitalChengdu 610095Sichuan ProvinceChina

Glaucoma is a common and complex neurodegenerative disease characterized by progressive loss of retinal ganglion cells(RGCs)and axons.Currently,there is no effective method to address the cause of RGCs degeneration.However,studies on neuroprotective strategies for optic neuropathy have increased in recent years.Cell replacement and neuroprotection are major strategies for treating glaucoma and optic neuropathy.Regenerative medicine research into the repair of optic nerve damage using stem cells has Received considerable attention.Stem cells possess the potential for multidirectional differentiation abilities and are capable of producing RGCfriendly microenvironments through paracrine effects.This article reviews a thorough researches of recent advances and approaches in stem cell repair of optic nerve injury,raising the controversies and unresolved issues surrounding the future of stem cells.

关键词： stem cell glaucoma retinal ganglion cell optic nerve axon regeneration

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Causal associations between gastroesophageal reflux disease and essential hypertension: A bidirectional Mendelian randomization study

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World Journal of Clinical Cases 2024年第5期12卷 880-890页

作者： Ning Wei ming-Hui liu yu-Hu Song Department of Gastroenterology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

BACKGROUND Clinical studies have reported that patients with gastroesophageal reflux disease(GERD)have a higher prevalence of hypertension.AIM To performed a bidirectional Mendelian randomization(MR)analysis to investi-gate the causal link between GERD and essential hypertension.METHODS Eligible single nucleotide polymorphisms(SNPs)were selected,and weighted median,inverse variance weighted(IVW)as well as MR egger(MR-Egger)re-gression were used to examine the potential causal association between GERD and hypertension.The MR-Pleiotropy RESidual Sum and Outlier analysis was used to detect and attempt to reduce horizontal pleiotropy by removing outliers SNPs.The MR-Egger intercept test,Cochran’s Q test and“leave-one-out”sen-sitivity analysis were performed to evaluate the horizontal pleiotropy,heterogen-eities,and stability of single instrumental variable.RESULTS IVW analysis exhibited an increased risk of hypertension(OR=1.46,95%CI:1.33-1.59,P=2.14E-16)in GERD patients.And the same result was obtained in replication practice(OR=1.002,95%CI:1.0008-1.003,P=0.000498).Meanwhile,the IVW analysis showed an increased risk of systolic blood pressure(β=0.78,95%CI:0.11-1.44,P=0.021)and hypertensive heart disease(OR=1.68,95%CI:1.36-2.08,P=0.0000016)in GERD patients.Moreover,we found an decreased risk of Barrett's esophagus(OR=0.91,95%CI:0.83-0.99,P=0.043)in essential hypertension patients.CONCLUSION We found that GERD would increase the risk of essential hypertension,which provided a novel prevent and therapeutic perspectives of essential hypertension.

关键词： Gastroesophageal reflux disease Essential hypertension Hypertensive heart disease Mendelian randomization study

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Novel subtype of obesity influencing the outcomes of sleeve gastrectomy:Familial aggregation of obesity

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World Journal of Gastroenterology 2024年第13期30卷 1887-1898页

作者： Ze-yu Wang yun-Fei Qu Tian-ming yu Zeng-Lin liu yu-Gang Cheng ming-Wei Zhong San-yuan Hu Department of General Surgery The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan HospitalJinan 250000Shandong ProvinceChina Department of Postgraduate Shandong First Medical University and Shandong Academy of Medical SciencesJinan 250000Shandong ProvinceChina Department of General Surgery Shandong Provincial Qianfoshan HospitalCheeloo College of Medicine Shandong UniversityJinan 250000Shandong ProvinceChina State Key Laboratory of Integration and Innovation of Classic Formula and Modern Chinese Medicine Lunan Pharmaceutical Group Co.Ltd.Linyi 276005Shandong ProvinceChina

BACKGROUND Differences in the preoperative characteristics and weight loss outcomes after sleeve gastrectomy(SG)between patients with familial aggregation of obesity(FAO)and patients with sporadic obesity(SO)have not been elucidated.AIM To explore the impact of SG on weight loss and the alleviation of obesity-related comorbidities in individuals with FAO.METHODS A total of 193 patients with obesity who underwent SG were selected.Patients with FAO/SO were matched 1:1 by propensity score matching and were categorized into 4 groups based on the number of first-degree relatives with obesity(1 SO vs 1FAO,2SO vs 2FAO).The baseline characteristics,weight loss outcomes,prevalence of obesity-related comorbidities and incidence of major surgeryrelated complications were compared between groups.RESULTS We defined FAO as the presence of two or more first-degree relatives with obesity.Patients with FAO did not initially show significant differences in baseline data,short-term postoperative weight loss,or obesity-related comorbidities when compared to patients with SO preoperatively.However,distinctions between the two groups became evident at the two-year mark,with statistically significant differences in both percentage of total weight loss(P=0.006)and percentage of excess weight loss(P<0.001).The FAO group exhibited weaker remission of type 2 diabetes mellitus(T2DM)(P=0.031),hyperlipidemia(P=0.012),and non-alcoholic fatty liver disease(NAFLD)(P=0.003)as well as a lower incidence of acid reflux(P=0.038).CONCLUSION FAO patients is associated with decreased mid-to-long-term weight loss outcomes;the alleviation of T2DM,hyperlipidemia and NAFLD;and decreased incidence of acid reflux postoperatively.

关键词： Obesity Bariatric surgery Sleeve gastrectomy Family history Weight loss

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