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Regional carrying capacity: case studies of Bohai Rim area

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Journal of Geographical Sciences 2002年第2期12卷 54-62页

作者： Yu Dan-lin mao han-ying Department of Geography University of Wisconsin Milwaukee USA Institute of Geographic Sciences and Natural Resources Research CAS Beijing China

Carrying capacity research has been carried out for a long time. However, synthesized carrying capacity researches based on systematic views began only in the 1970s. There is even less work done in China. This paper tries to address both synthesized carrying capacity research and its utilization in China. State spaces method from the systematic science was borrowed to construct the conceptual model of regional carrying capacity. Based on the conceptual model and the surveys in the Bohai Rim area, we construct a representative indicators system for quantifying regional carrying capacity in the Bohai Rim. While employing system dynamic models we simulated the evolving trend of both the regional carrying states and regional carrying capacity from 1999 to 2015. The results proved the statement that Bohai Rim is overall over-capacity for a long time and will be over-capacity in the foreseeable future. Among all the restriction factors, water shortage and environmental pollution stand out to be the two primary obstacles for Bohai Rims sustainable development. Regional differentiation analysis further indicates that coastal areas of the Bohai Rim burden more than its overall level. However, Shandong province shows some good signs in addressing the regional carrying capacity issues. The research is successful in addressing the quantification of regional carrying capacity issues, but nonetheless it needs further refinery and more information.

关键词： regional carrying capacity regional carrying state Bohai Rim area state space

Acute extensive portal and mesenteric venous thrombosis after splenectomy:Treated by interventional thrombolysis with transjugular approach

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World Journal of Gastroenterology 2009年第24期15卷 3038-3045页

作者： mao-Qiang Wang han-ying Lin Li-Ping Guo Feng-Yong Liu Feng Duan Zhi-Jun Wang Department of Interventional Radiology Chinese PLA General Hospital Beijing 100853 China

AIM:To present a series of cases with symptomatic acute extensive portal vein(PV)and superior mesenteric vein(SMV)thrombosis after splenectomy treated by transjugular intrahepatic approach catheter-directed thrombolysis. METHODS:A total of 6 patients with acute extensive PV-SMV thrombosis after splenectomy were treated by transjugular approach catheter-directed thrombolysis. The mean age of the patients was 41.2 *** access to the portal system via the transjugular approach,pigtail catheter fragmentation of clots, local urokinase injection,and manual aspiration thrombectomy were used for the initial treatment of PV-SMV thrombosis,followed by continuous thrombolytic therapy via an indwelling infusion catheter in the SMV,which was performed for three to six days. Adequate anticoagulation was given during treatment, throughout hospitalization,and after discharge. RESULTS:Technical success was achieved in all 6 *** improvement was seen in these patients within 12-24 h of the *** complications were *** 6 patients were discharged 6-14 d(8±2.5 d)after *** mean duration of follow-up after hospital discharge was 40±16.5 *** and contrast-enhanced computed tomography confirmed patency of the PV and SMV,and no recurrent episodes of PV-SMV thrombosis developed during the follow-up period. CONCLUSION:Catheter-directed thrombolysis via transjugular intrahepatic access is a safe and effective therapy for the management of patients with symptomatic acute extensive PV-SMV thrombosis.

关键词： Mechanical thrombectomy Portal vein Splenectomy Superior mesenteric vein Thrombolysis Thrombosis

Numerical simulation of transient flow in horizontal drainage systems

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Water Science and Engineering 2009年第1期2卷 74-85页

作者： Ze-yu mao han XIAO ying LIU ying-jun HU Department of Hydraulic Engineering Tsinghua University Beijing 100084 P. R. China

A numerical simulation model based on the characteristic-based finite-difference method with a time-line interpolation scheme was developed for predicting transient free surface flow in horizontal drainage systems. The fundamental accuracy of the numerical model was first clarified by comparison with the experimental results for a single drainage pipe. Boundary conditions for junctions and bends, which are often encountered in drainage systems, were studied both experimentally and numerically. The numerical model was applied to an actual drainage system. Comparison with a full-scale model experiment indicates that the model can be used to accurately predict flow characteristics in actual drainage networks.

关键词： transient flow drainage systems time-line interpolation urbanization

Basic thoughts and practice of China's regional development planning in new period

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Journal of Geographical Sciences 1999年第2期9卷 135-140页

作者： mao han-ying FANG Chuang-lin YUDan-lin (Institute of Geography, Chinese Academy of Sciences, Beliing 100101, China)

Regional development planning is one of the 'hot spots' in the field of human geography in China Based on brief retrospection and reviewing of its development since the 1980s, this paper discusses the basic thoughts of regional development planning under the socialit market economy, i.e.,to work out planning of flexibility, sustainability, multi-objective coordination and high effective practicability. In line with these thoughts, the paper puts forwards boo countermeasure in the practice of working out a high effective regional developmed planning. These countermeasures are to strengthen research on market factors, to take the coordinated development between the economy,society and PRED as the main line of regional development to correctly deal with the relationship between qualitative analysis and quantitative research and to emphasize on researches of regional policies.

关键词： regional development planning China market economy theory

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混沌特征量识别切削颤振的试验研究

振动与冲击 2015年第16期34卷 99-103页

作者：毛汉颖刘畅刘永坚毛汉领广西科技大学汽车与交通学院广西柳州542506 广西大学机械工程学院南宁530004

针对切削颤振具有的非线性,传统信号处理方法不能全面揭示颤振特征及难以识别预报等问题,通过改变切削速度及深度的多组切削试验,获得从平稳切削到颤振状态完整过程的多组振动加速度信号,采用关联维数、最大Lyapunov指数及Kolmogorov熵... 详细信息

针对切削颤振具有的非线性,传统信号处理方法不能全面揭示颤振特征及难以识别预报等问题,通过改变切削速度及深度的多组切削试验,获得从平稳切削到颤振状态完整过程的多组振动加速度信号,采用关联维数、最大Lyapunov指数及Kolmogorov熵等分析测试信号的混沌特征。结果表明,三个混沌特征量均能从不同角度较好揭示切削过程从平稳到颤振的变化规律。多混沌特征可能将是识别预报颤振的新方向。

关键词：切削颤振混沌特征识别

声发射信号检测中谐振传导杆的设计与试验研究

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振动与冲击 2014年第17期33卷 179-183页

作者：毛汉颖黄振峰韦花貌毛汉领广西科技大学汽车系广西柳州542506 广西大学机械学院南宁530004

为了突破条件限制检测微弱声发射信号,常用检测传导杆,但信号有衰减。首次提出了采用共振理论设计声发射检测传导杆的方法,设计研制了不同材料、不同谐振长度的谐振传导杆;断铅模拟声发射信号的试验表明,谐振传导杆对声发射信号具有幅... 详细信息

为了突破条件限制检测微弱声发射信号,常用检测传导杆,但信号有衰减。首次提出了采用共振理论设计声发射检测传导杆的方法,设计研制了不同材料、不同谐振长度的谐振传导杆;断铅模拟声发射信号的试验表明,谐振传导杆对声发射信号具有幅值放大和带通滤波功能,其效果与传导杆的材料和结构尺寸有关。

关键词：声发射检测谐振传导杆幅值放大

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新时期区域规划的理论、方法与实践

地域研究与开发 2005年第6期24卷 1-6页

作者：毛汉英中国科学院地理科学与资源研究所北京100101

文章根据新时期中国区域规划的特点,从促进区域协调发展、政府职能转变与加强空间调控、完善国家规划体系等方面,阐明了加强区域规划的迫切性;探讨了区域规划的理论基础和方法论基础;并根据作者近3年来的实践,对新时期区域规划的内容提... 详细信息

文章根据新时期中国区域规划的特点,从促进区域协调发展、政府职能转变与加强空间调控、完善国家规划体系等方面,阐明了加强区域规划的迫切性;探讨了区域规划的理论基础和方法论基础;并根据作者近3年来的实践,对新时期区域规划的内容提出了有益的建议。

关键词：区域规划理论方法实践

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区域发展规划指标体系建立方法探讨

地理学报 1999年第5期54卷 410-419页

作者：方创琳毛汉英北京大学城市与环境学系北京100871 中国科学院地理研究所北京100101

本文设计出市场经济条件下区域发展规划指标体系的基本框架与内容，探讨了熵技术支持下规划指标体系权系数赋值的层次分析法和专家群民主决策支持下定性指标定量转化的赋权方法，以中国西部地区为例建立了规划指标体系支持下区域发展... 详细信息

本文设计出市场经济条件下区域发展规划指标体系的基本框架与内容，探讨了熵技术支持下规划指标体系权系数赋值的层次分析法和专家群民主决策支持下定性指标定量转化的赋权方法，以中国西部地区为例建立了规划指标体系支持下区域发展水平的多层次多目标模糊综合测度模型，并对区域发展总体水平进行分析讨论。该指标体系有助于掌握区域发展水平的动态变化规律与演变趋势，进而适时适度地调整区域发展方向，是我们有针对性地制定达到特定发展水平区域发展规划，并制定出提高区域发展水平有效途径的重要手段。

关键词：区域发展规划指标体系权系数中国西部地区

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棒料制造齿圈毛坯成形工艺的数值仿真

塑性工程学报 2015年第5期22卷 18-23页

作者：毛汉颖毛汉领叶朋黄振峰广西科技大学汽车与交通学院柳州545006 广西大学机械工程学院南宁530004

为提高生产效率和材料利用率,针对大尺寸齿圈毛坯的特点,提出了以棒料为坯料生产大尺寸齿圈毛坯的新工艺。利用数值仿真分析方法研究其关键成形工艺,对所设计的一次成形可对焊圆环的辊圆成形装置建立数学模型,对棒料成形可对焊圆环过程... 详细信息

为提高生产效率和材料利用率,针对大尺寸齿圈毛坯的特点,提出了以棒料为坯料生产大尺寸齿圈毛坯的新工艺。利用数值仿真分析方法研究其关键成形工艺,对所设计的一次成形可对焊圆环的辊圆成形装置建立数学模型,对棒料成形可对焊圆环过程进行数值模拟并进行实验验证,分析了棒料成形的可行性。模拟和实验结果表明,依据仿真结果设计的辊圆成形装置可实现棒料成形,该装置具有实用性。对齿圈毛坯的模锻过程进行数值仿真,获得了齿圈毛坯成形过程中的关键工艺参数,对实际生产具有指导意义。

关键词：齿圈毛坯数值仿真焊圆环工艺模锻工艺