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Comparative Analysis of Metro Passengers’Mobility Patterns and Jobs-housing Balance of Metropolitan
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作者 HUANG Yiman ZHANG Anshu +1 位作者 SU Yuezhu SHI Wenzhong 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第2期1-17,共17页
The advent of the big data era has provided many types of transportation datasets,such as metro smart card data,for studying residents’mobility and understanding how their mobility has been shaped and is shaping the ... The advent of the big data era has provided many types of transportation datasets,such as metro smart card data,for studying residents’mobility and understanding how their mobility has been shaped and is shaping the urban space.In this paper,we use metro smart card data from two Chinese metropolises,Shanghai and Shenzhen.Five metro mobility indicators are introduced,and association rules are established to explore the mobility patterns.The proportion of people entering and exiting the station is used to measure the jobs-housing balance.It is found that the average travel distance and duration of Shanghai passengers are higher than those of Shenzhen,and the proportion of metro commuters in Shanghai is higher than that of Shenzhen.The jobs-housing spatial relationship in Shenzhen based on metro travel is more balanced than that in Shanghai.The fundamental reason for the differences between the two cities is the difference in urban morphology.Compared with the monocentric structure of Shanghai,the polycentric structure of Shenzhen results in more scattered travel hotspots and more diverse travel routes,which helps Shenzhen to have a better jobs-housing balance.This paper fills a gap in comparative research among Chinese cities based on transportation big data analysis.The results provide support for planning metro routes,adjusting urban structure and land use to form a more reasonable metro network,and balancing the jobs-housing spatial relationship. 展开更多
关键词 metro smart card data mobility patterns association rules jobs-housing balance
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Balance control during gait initiation: State-of-the-art and research perspectives 被引量:2
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作者 Eric Yiou Teddy Caderby +2 位作者 Arnaud Delafontaine Paul Fourcade Jean-Louis Honeine 《World Journal of Orthopedics》 2017年第11期815-828,共14页
It is well known that balance control is affected by aging, neurological and orthopedic conditions. Poor balance control during gait and postural maintenance are associated with disability, falls and increased mortali... It is well known that balance control is affected by aging, neurological and orthopedic conditions. Poor balance control during gait and postural maintenance are associated with disability, falls and increased mortality. Gait initiation-the transient period between the quiet standing posture and steady state walking-is a functional task that is classically used in the literature to investigate how the central nervous system(CNS) controls balance during a whole-body movement involving change in the base of support dimensions and center of mass progression. Understanding how the CNS in able-bodied subjects exerts this control during such a challenging task is a prerequisite to identifying motor disorders in populations with specific impairments of the postural system. It may also provide clinicians with objective measures to assess the efficiency of rehabilitation programs and better target interventions according to individual impairments. The present review thus proposes a state-of-the-art analysis on:(1) the balance control mechanisms in play during gait initiation in able bodied subjects and in the case of some frail populations; and(2) the biomechanical parameters used in the literature to quantify dynamic stability during gait initiation. Balance control mechanisms reviewed in this article included anticipatory postural adjustments, stance leg stiffness, foot placement, lateral ankle strategy, swing foot strike pattern and vertical center of mass braking. Based on this review, the following viewpoints were put forward:(1) dynamic stability during gait initiation may share a principle of homeostatic regulation similar to most physiological variables, where separate mechanisms need to be coordinated to ensure stabilization of vital variables, and consequently; and(2) rehabilitation interventions which focus on separate or isolated components of posture, balance, or gait may limit the effectiveness of current clinical practices. 展开更多
关键词 balance control Anticipatory POSTURAL ADJUSTMENTS Leg stiffness FOOT placement Lateral ANKLE strategy FOOT STRIKE pattern Vertical center of mass braking Dynamic stability Gait initiation Biomechanics
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China's Sovereign Balance Sheet and Its Risk Assessment 被引量:1
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作者 李扬 张晓晶 +2 位作者 常欣 汤铎铎 李成 《China Economist》 2012年第6期78-89,共12页
Using available data and necessary estimations, this paper provides a tentative picture of the balance sheet of China's sovereign account between 2000 and 2010. The main findings indicate that the net worth of China... Using available data and necessary estimations, this paper provides a tentative picture of the balance sheet of China's sovereign account between 2000 and 2010. The main findings indicate that the net worth of China's sovereign assets had been positive and increasing during the period under review. This implies that the Chinese government has sufficient sovereign assets to cover its sovereign liabilities, therefore the likelihood of a sovereign debt crisis in China is extremely low in the near term. Moreover, although China's leverage ratio (total liabilities/GDP) is far lower compared to advanced economies, it seems higher than that of other major emerging economies such as Brazil, Russia, and India (BRIC). In fact, the leverage ratio has been increasing rapidly over recent years and requires special attention. In particular, according to sector-specific analysis, high corporate liability ratios (percentage to GDP) constitute a major concern of China's national balance sheet. In 2010, this liability ratio exceeded l OO percent, which exceeds the 90 percent level observed in OECD countries. Lastly, this paper concludes that a sustainable economic growth and structural transformation of growth model are the fundamental means to taming China's balance sheet risks. 展开更多
关键词 balance sheet approach sovereign balance sheet leverage ratio transformation of development pattern.
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新疆北部城市碳排放时空分异与碳平衡分区
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作者 冶建明 翟梦瑶 +1 位作者 陈志新 李禹慷 《上海国土资源》 2024年第1期93-101,共9页
研究城市土地利用碳排放时空格局与碳平衡分区,对实现碳减排和“双碳”目标至关重要。以新疆北部46个县市为研究区,利用土地利用与能源数据,通过碳排放系数法计算2000—2020年土地利用碳排放,分析碳排放量时空演变情况,对各县市进行碳... 研究城市土地利用碳排放时空格局与碳平衡分区,对实现碳减排和“双碳”目标至关重要。以新疆北部46个县市为研究区,利用土地利用与能源数据,通过碳排放系数法计算2000—2020年土地利用碳排放,分析碳排放量时空演变情况,对各县市进行碳平衡分区。结果表明:(1)碳排放量呈总体上升趋势,2016—2020年呈现指数型上升的趋势,碳吸收量缓慢下降,碳排放强度先下降后上升,碳排放量远大于碳吸收量。(2)碳排放主要来源于建设用地,天山北坡城市为主要碳排放城市,碳吸收主要来源于草地与林地,伊犁河谷地区、阿尔泰山南部等地城市为主要碳吸收城市。(3)碳排放空间相关性逐渐减弱,热点区集中分布在克拉玛依市附近,冷点区集中分布在伊犁州与阿勒泰地区。(4)依据经济承载力系数、生态承载力系数以及碳排放量划分为碳汇功能区、碳汇优化区、低碳经济区、碳源优化区和高碳控制区五个碳平衡分区。 展开更多
关键词 土地利用碳排放 时空格局 碳平衡分区 新疆北部
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面向时空轨迹流的共同运动模式分布式挖掘算法
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作者 余舒鹏 吴春雨 +1 位作者 赵斌 吉根林 《数据采集与处理》 CSCD 北大核心 2024年第5期1163-1181,共19页
从轨迹流中挖掘共同运动模式指在同一时间内发现具有相同运动行为的移动对象群体,在交通物流、疫情防控等方面具有重要意义。然而,现有研究面对大规模轨迹流数据难以做到快速响应。因此,本文首先提出了基于滑动窗口的分布式时空轨迹流... 从轨迹流中挖掘共同运动模式指在同一时间内发现具有相同运动行为的移动对象群体,在交通物流、疫情防控等方面具有重要意义。然而,现有研究面对大规模轨迹流数据难以做到快速响应。因此,本文首先提出了基于滑动窗口的分布式时空轨迹流共同运动模式挖掘算法,使用滑动窗口计算模型代替快照计算模型,利用增量式更新代替重新计算,使算法更适用于无界且快速到达的轨迹流数据,在效率和有效性方面呈现更好的性能。其次,针对分布式流处理系统中由于负载不均导致性能下降问题,提出了自适应多级动态数据分发策略,该策略能够适应轨迹流数据的动态变化,实时监测系统负载情况并根据负载不均的程度做出适当调整。最后,基于分布式流处理平台Flink实现了上述功能,并通过真实数据集的实验证明本文提出的算法比基准方法具有更快的响应速度和更低的延迟。 展开更多
关键词 时空轨迹流 共同运动模式 分布式系统 滑动窗口 负载均衡
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NFV场景下基于协议和目的端口的负载均衡策略
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作者 张人杰 李頔 +1 位作者 王方 刘慧 《湖南邮电职业技术学院学报》 2024年第3期1-7,共7页
网络功能虚拟化(NFV)技术为网络安全设施的灵活性和可扩展性提供了创新解决方案。以Snort作为研究核心,深入分析其快速模式匹配器的实现机制,并基于此提出了一种创新的负载均衡策略。该策略通过优化流量处理机制,以较小的内存占用实现... 网络功能虚拟化(NFV)技术为网络安全设施的灵活性和可扩展性提供了创新解决方案。以Snort作为研究核心,深入分析其快速模式匹配器的实现机制,并基于此提出了一种创新的负载均衡策略。该策略通过优化流量处理机制,以较小的内存占用实现高效的流量检测,显著减少了硬件资源需求。通过实验验证,该策略在NFV环境中相较于传统五元组哈希策略实现了超过50%的性能提升。 展开更多
关键词 网络功能虚拟化 负载均衡 快速模式匹配器
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八段锦摇头摆尾式联合PNF运动模式对脑卒中患者平衡功能的影响
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作者 肖伯恒 马丽虹 张振国 《山东中医杂志》 2024年第11期1261-1266,共6页
目的:观察八段锦摇头摆尾式联合PNF颈部运动模式对脑卒中患者平衡功能的影响。方法:筛选60例符合纳入标准的脑卒中患者,采用随机数字表法分为对照组和观察组各30例。对照组患者接受常规康复治疗,观察组在对照组基础上联合运用八段锦摇... 目的:观察八段锦摇头摆尾式联合PNF颈部运动模式对脑卒中患者平衡功能的影响。方法:筛选60例符合纳入标准的脑卒中患者,采用随机数字表法分为对照组和观察组各30例。对照组患者接受常规康复治疗,观察组在对照组基础上联合运用八段锦摇头摆尾式及PNF颈部运动模式,两组患者均接受治疗3周。分别于治疗前后进行脑卒中患者姿势评定量表(PASS)评分、躯干损伤量表(TIS)评分、Berg平衡量表(BBS)评分评定。结果:治疗3周后,两组PASS评分、TIS评分、BBS评分均较治疗前明显提高(P<0.01),且观察组评分改善较对照组更明显(P<0.05)。TIS评分分项中静态坐位平衡及动态坐位平衡观察组与对照组改善差异有统计学意义(P<0.05),协调分项观察组与对照组改善差异无统计学意义(P>0.05)。结论:八段锦摇头摆尾式与PNF颈部运动模式相结合,可有效提升脑卒中患者姿势控制及平衡功能,较常规治疗展现出更佳的疗效。 展开更多
关键词 八段锦 摇头摆尾式 PNF颈部运动模式 脑卒中 姿势控制 平衡功能
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基于GIS空间洛伦兹曲线的中小学均衡性和公平性分析与评价研究
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作者 曾超华 韩岳芳 +2 位作者 何冰 程春梅 姚姣凤 《测绘与空间地理信息》 2024年第5期48-51,共4页
利用GIS空间分析中分布模式的测度,对浙江省杭州市区内中小学的空间分布进行均衡性分析,并结合洛伦兹曲线和基尼系数对公平性进行研究,进而对区域中小学均衡性和公平性进行评价。结果表明:杭州市中小学教育资源空间上整体呈现显著聚集情... 利用GIS空间分析中分布模式的测度,对浙江省杭州市区内中小学的空间分布进行均衡性分析,并结合洛伦兹曲线和基尼系数对公平性进行研究,进而对区域中小学均衡性和公平性进行评价。结果表明:杭州市中小学教育资源空间上整体呈现显著聚集情况,存在明显的不均衡,但在整体公平性上表现出较平均的情况。该方法可为今后区域的规划、优化教育资源的配置,提供科学依据。 展开更多
关键词 分布模式的测度 中小学 洛伦兹曲线 基尼系数 均衡性和公平性
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“动—静”结合视角下黄河中下游粮食生产全周期碳平衡测度及分区
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作者 路昌 王之语 +3 位作者 郭沁林 蔡雪芹 郝灿书 孙增禹 《中国土地科学》 CSSCI CSCD 北大核心 2024年第8期109-123,共15页
研究目的:构建粮食生产全周期碳收支体系,基于“动—静”结合视角测算黄河中下游粮食生产碳平衡水平,针对不同碳平衡水平分区提出差异化调控策略,可为全面反映粮食生产碳平衡水平、协同推进粮食绿色生产提供支持与参考。研究方法:生命... 研究目的:构建粮食生产全周期碳收支体系,基于“动—静”结合视角测算黄河中下游粮食生产碳平衡水平,针对不同碳平衡水平分区提出差异化调控策略,可为全面反映粮食生产碳平衡水平、协同推进粮食绿色生产提供支持与参考。研究方法:生命周期评价法,碳转化系数法,经验公式法,静态平衡指数,动态平衡指数,信息熵模型。研究结果:(1)黄河中下游粮食生产碳排放和碳吸收均为增长趋势,空间上均呈“西北低,东南高”态势。(2)黄河中下游粮食生产碳收支静态平衡指数呈“西北低,东南高”分布,地区均值波动下降,各地市存在直升型、直降型、U型和倒U型4种演变趋势,粮食生产碳收支动态平衡指数具有显著时空异质性。(3)黄河中下游粮食生产碳平衡水平分区呈“西北失衡,东南平衡”分布,格局结构有序性历经“较有序—较无序—有序—无序”波动。研究结论:贡献度视角下黄河中下游部分地市粮食生产碳收支仍存在失衡情况,需进一步施行针对性和差异性的粮食绿色生产策略。 展开更多
关键词 粮食生产碳平衡 静态平衡水平 动态平衡水平 生命周期评价法 分区格局 黄河中下游
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Tilt Angle Optimality Criteria for Stand Alone PV Systems
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作者 Mohammad Abu-Naser 《Journal of Power and Energy Engineering》 2024年第3期1-18,共18页
The conventional approach to optimizing tilt angles for fixed solar panels aims to maximize energy generation over the entire year. However, in the context of a supply controlled electric grid, where solar energy avai... The conventional approach to optimizing tilt angles for fixed solar panels aims to maximize energy generation over the entire year. However, in the context of a supply controlled electric grid, where solar energy availability varies, this criterion may not be optimal. This study explores two alternative optimization criteria focused on maximizing baseload supply potential and minimizing required storage capacity to address seasonality in energy generation. The optimal tilt angles determined for these criteria differed significantly from the standard approach. This research highlights additional factors crucial for designing solar power systems beyond gross energy generation, essential for the global transition towards a fully renewable energy-based electric grid in the future. 展开更多
关键词 Electric Grid Fixed Solar Panels Optimal PV Tilt Angle Seasonal Solar Variability Renewable Energy supply-demand balance
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优质均衡视域下新优质学校的价值意蕴和实践样态
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作者 成文辉 《当代教育理论与实践》 2024年第3期46-53,共8页
推进义务教育优质均衡发展,是实现从“有学上”到“上好学”的迫切需要,是建设高质量教育体系的关键环节。从本质上来说,优质均衡就是要追求优质的学校教育。新优质学校办学不看分数,评价不看升学率,而是关注每位学生的成长,关注如何让... 推进义务教育优质均衡发展,是实现从“有学上”到“上好学”的迫切需要,是建设高质量教育体系的关键环节。从本质上来说,优质均衡就是要追求优质的学校教育。新优质学校办学不看分数,评价不看升学率,而是关注每位学生的成长,关注如何让教育更加有效、师生关系更加融洽、学生个性化学习需求更加满足,在学校育人目标、德育工作、学生发展、课程教学、队伍建设、学校文化、教育数字化等方面都会表现出独特的内涵与特征。 展开更多
关键词 新优质学校 义务教育 均衡发展 实践样态
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基于对称与均衡形式美法则的壮族背带纹样在女装设计中的应用
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作者 覃清华 《武汉纺织大学学报》 2024年第2期56-62,共7页
壮族背带纹样是壮族生活物化的精神载体,凝结着壮族的智慧与美好生活的向往,为更好的传承和提升壮族背带纹样与当代设计的多元融合。文章通过分析国内外女装品牌服饰中纹样装饰的方式及效果,归纳总结出基于对称与均衡形式美法则视角下,... 壮族背带纹样是壮族生活物化的精神载体,凝结着壮族的智慧与美好生活的向往,为更好的传承和提升壮族背带纹样与当代设计的多元融合。文章通过分析国内外女装品牌服饰中纹样装饰的方式及效果,归纳总结出基于对称与均衡形式美法则视角下,壮族背带纹样与女装设计多元融合的理论依据和实践路径。研究表明:基于对称与均衡的形式美法则能够有效的实现壮族背带纹样的文化价值和装饰审美,为壮族背带纹样传承与创新设计应用提供系统性的转化思路。 展开更多
关键词 壮族背带纹样 对称与均衡形式美法则 多元融合 设计应用
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Spatial patterns of ecological carrying capacity supply-demand balance in China at county level 被引量:27
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作者 LIU Dong FENG Zhiming YANG Yanzhao YOU Zhen 《Journal of Geographical Sciences》 SCIE CSCD 2011年第5期833-844,共12页
A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependenci... A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependencies between human and nature.China's ecological balance between supply and demand has become a global concern and is widely debated.In this study the 'Ecological Footprint' method was used to analyze the supply-demand balance of China's ecological carrying capacity.Firstly,the ecological supply and demand balance was calculated and evaluated,and secondly,the ecological carrying capacity index (ECCI) was derived for each county of China in 2007,and finally this paper systematically evaluated the ecological carrying capacity supply-demand balance of China.The results showed that ecological deficit appeared to be the main characteristic of ecological carrying capacity supply-demand balance in 2007 of China at county scale.In general,more than four-fifths of the Chinese population was concentrated in less than one-third of the land area and more than two-thirds of the land area was inhabited by less than one-fifth of the population.The spatial distribution of the ecological carrying capacity demand-supply was unbalanced ranging from significant overloading to affluence from southeastern to northwestern part of China.It appeared to be more dominant in regions located at coastal areas which are attracted by migrants and had a generally higher population density.Along with the rapid development and urbanization trends in China,ecological deficits in these regions will become more severe. 展开更多
关键词 ecological footprint ecological carrying capacity ecological carrying capacity index supply-demand balance GIS China
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CFD simulation of spontaneous coal combustion in irregular patterns of goaf with multiple points of leaking air 被引量:4
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作者 LI Zong-xiang 《Journal of China University of Mining and Technology》 EI 2008年第4期504-508,515,共6页
Based on the non-linear air leakage seepage equation for an anisotropic porous medium, on the seepage diffusion equation of multicomponent gas and on the seepage synthetic heat transfer equation of a porous medium, th... Based on the non-linear air leakage seepage equation for an anisotropic porous medium, on the seepage diffusion equation of multicomponent gas and on the seepage synthetic heat transfer equation of a porous medium, the numerical model for field flow problems of irregular patterns of a goaf with multiple points of leaking air is established and simultaneously solved by the upwind mode finite element method (G3 computer program). According to the complexity of irregular patterns of a goaf with multiple points of leaking air, the flow pattern in a large area of such a goaf and the variation in gases of methane, oxygen and CO and in temperature are theoretically described. In the calculation, the goaf is regarded as a caving anisotropic medium and the coupling effect of methane effusion on spontaneous combustion is considered. The simulation results agree well with practical experience. In addition, the spontaneous combustion process is also simulated, indicating that 1) the spontaneous combustion often takes place near the area where fresh air leaks in and 2) the fire sources can be classified into static and dynamic zones. Therefore, in practical fire preventing and extinguishing, we should clearly distinguish the upstream air leaking points from the downstream ones in order to take proper measures for leakage stopping. 展开更多
关键词 irregular pattern of goaf multi-points of air leaking spontaneous combustion temperature field fire zone distribution pressure balance
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Area-Efficient Low Power CMOS Image Sensor Readout Circuit with Fixed Pattern Noise Cancellation 被引量:2
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作者 赵士彬 姚素英 +1 位作者 聂凯明 徐江涛 《Transactions of Tianjin University》 EI CAS 2010年第5期342-347,共6页
A low cost of die area and power consumption CMOS image sensor readout circuit with fixed pattern noise(FPN) cancellation is proposed.By using only one coupling capacitor and switch in the double FPN cancelling correl... A low cost of die area and power consumption CMOS image sensor readout circuit with fixed pattern noise(FPN) cancellation is proposed.By using only one coupling capacitor and switch in the double FPN cancelling correlative double sampling(CDS),pixel FPN is cancelled and column FPN is stored and eliminated by the sampleand-hold operation of digitally programmable gain amplifier(DPGA).The bandwidth balance technology based on operational amplifier(op-amp) sharing is also introduced to decrease the power dissi... 展开更多
关键词 imaging system image sensor low power electronic CAPACITOR operational amplifier fixed pattern noise bandwidth balance technology op-amp sharing
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舒兰教授基于“平衡脏腑”“证症结合”思想论治儿童抽动障碍 被引量:1
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作者 陶洪 周姗 +1 位作者 彭昕欣 舒兰 《湖南中医药大学学报》 CAS 2023年第6期1070-1073,共4页
抽动障碍(tic disorder,TD)是儿童临床常见的难治性疾病之一,其发病机制复杂,诱因较多,易共患其他精神性疾病,目前缺乏疗效确切的治疗方案。国家级名中医舒兰认为TD的核心病机为风胜则动,提出“五脏六腑皆可致抽,非独在肝”的学术观点,... 抽动障碍(tic disorder,TD)是儿童临床常见的难治性疾病之一,其发病机制复杂,诱因较多,易共患其他精神性疾病,目前缺乏疗效确切的治疗方案。国家级名中医舒兰认为TD的核心病机为风胜则动,提出“五脏六腑皆可致抽,非独在肝”的学术观点,以平衡脏腑功能、辨证与辨症结合为基本治疗原则。外风引动以疏风止痉、清热利咽为法,方选清解止抽方治疗;内风引动以平衡脏腑为法,常用导赤散、参苓白术散、泻黄散、龙胆泻肝汤、知柏地黄汤等加减治疗,并强调临证时需证症结合、相互兼顾。“平衡脏腑”“证症结合”的思想为儿童TD提供新的诊疗思路。 展开更多
关键词 抽动障碍 平衡脏腑 证症结合 清解止抽方 舒兰 医案
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Spatial and Temporal Patterns of Supply and Demand Balance of Water Supply Services in the Dongjiang Lake Basin and Its Beneficiary Areas 被引量:2
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作者 徐洁 肖玉 +1 位作者 李娜 王浩 《Journal of Resources and Ecology》 CSCD 2015年第6期386-396,共11页
Water-related ecosystem services is a hot topic in ecological research. Water supply services are crucial to regional water cycles and water quantity balance. The Dongjiang Lake basin is a national priority river basi... Water-related ecosystem services is a hot topic in ecological research. Water supply services are crucial to regional water cycles and water quantity balance. The Dongjiang Lake basin is a national priority river basin in China where ecological compensation pilot programs concerning water resources and water supply services are top priorities for ecosystem service protection. We analyzed spatial and temporal patterns associated with generation and use of water supply services in the Dongjiang Lake basin using the In VEST model, socio-economic data and water resource data. We found that between 1995 and 2010, water yield in the Dongjiang Lake basin and its beneficiary areas increased before declining, varying 9350–12 400 m3 ha-1 y-1; average water yield peaked in 2000. The spatial distribution patterns of water yield during these years are similar, progressively decreasing from upstream to downstream with a remarkable reduction in surrounding areas of city clusters. Average water consumption of the basin and its beneficiary areas ranged from 2900–4450 m3 ha-1 y-1 between 1995 and 2010; the spatial distribution patterns of water consumption during these years are similar, dropping gradually from urban construction land to its surroundings with a stronger gradient between urban and rural areas. More water was consumed on both banks and surroundings of the lake. From 1995 to 2010, water supply fell short of demand for urban construction land and its proximity as well as areas along the lake. Water supply services were able to satisfy needs in other regions. The Changsha-Zhuzhou-Xiangtan city cluster suffers from the most strained water supply. 展开更多
关键词 ecosystem services water supply services Dongjiang Lake supply and demand balance spatial and temporal patterns
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The foundation of “The Max Area Pattern” and Its Training Significance
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作者 Yi Xu 《Open Journal of Applied Sciences》 2012年第4期159-165,共7页
by reference and simplifying the volume expressions of Barrel Theory, this paper puts forward the Double Bottleneck Concept, the Weights of plate as well as the K-value concept on the flex coefficient of the items ref... by reference and simplifying the volume expressions of Barrel Theory, this paper puts forward the Double Bottleneck Concept, the Weights of plate as well as the K-value concept on the flex coefficient of the items reflecting the comparative needing of the factors. It also advances the automatic arrangement on the position of each item and the Max Area Pattern representing the athletic diathesis and ability. It also analysis training pattern in different time-limitation by the Max Area Pattern based on the concept of Balanced-Development. 展开更多
关键词 the MAX Area pattern the Double BOTTLENECK Concept the FLEX coefficient the balanced-Development time-limitation
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肌力平衡:释义、内在机制及实践应用 被引量:4
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作者 聂秋 李丹阳 陈建 《中国体育科技》 CSSCI 北大核心 2023年第3期28-36,共9页
肌力平衡是影响运动表现的关键因素。梳理肌力平衡相关研究,归纳肌力平衡的概念和内涵,从动作控制的角度探讨其内在机制,并探索在运动损伤检测及体能训练中的应用。结论:1)肌力平衡是机体为适应内、外部刺激,神经肌肉系统高效维持静态... 肌力平衡是影响运动表现的关键因素。梳理肌力平衡相关研究,归纳肌力平衡的概念和内涵,从动作控制的角度探讨其内在机制,并探索在运动损伤检测及体能训练中的应用。结论:1)肌力平衡是机体为适应内、外部刺激,神经肌肉系统高效维持静态姿势和以最佳模式完成动态动作的能力,解剖结构、生物力学特性及生理功能是维持肌力平衡的内在机制;2)肌力平衡是高效完成动作控制的关键,肌力失衡是动作模式受损的诱因;3)运用等速肌力、力量及跳跃动作测试评估肌力平衡可以预测损伤风险;4)通过单侧力量训练、快速伸缩复合训练及核心区训练可有效改善运动中的肌力平衡。亟待探究不同项目运动员肌力平衡与运动损伤、动作模式及不同运动能力之间的关系,特别是基于肌力平衡探究特定运动技术的肌肉工作机制,挖掘肌力平衡的应用价值。 展开更多
关键词 肌力平衡 动作模式 肢体间平衡 肢体间不对称
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不同秸秆还田方式对玉米农田土壤CO_(2)排放量和碳平衡的影响 被引量:6
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作者 李金 任立军 +6 位作者 李晓宇 毕润学 金鑫鑫 虞娜 张玉玲 邹洪涛 张玉龙 《中国农业科学》 CAS CSCD 北大核心 2023年第14期2738-2750,共13页
【目的】探究秸秆还田方式对土壤CO_(2)排放特征及碳平衡的影响,为东北地区农田土壤固碳减排和秸秆还田方式的选择提供科学依据。【方法】采用田间微区试验,以玉米为供试作物,设置3种秸秆还田方式:秸秆浅层还田(QH)、秸秆深层还田(SH)... 【目的】探究秸秆还田方式对土壤CO_(2)排放特征及碳平衡的影响,为东北地区农田土壤固碳减排和秸秆还田方式的选择提供科学依据。【方法】采用田间微区试验,以玉米为供试作物,设置3种秸秆还田方式:秸秆浅层还田(QH)、秸秆深层还田(SH)和秸秆覆盖还田(FG),无秸秆还田(CK)处理为对照。利用LI-8100A土壤碳通量自动测定仪监测玉米生长季不同秸秆还田方式下土壤CO_(2)的排放特征,探讨土壤温度、含水量、pH、微生物量碳及氮磷钾速效养分和全量养分对土壤CO_(2)排放的影响,并分析不同还田方式下的土壤碳平衡。【结果】在玉米生长季,各处理土壤CO_(2)排放速率均表现为先升高后降低的趋势。土壤CO_(2)累积排放量表现为FG>QH>SH>CK处理,相较于SH处理,FG和QH处理土壤CO_(2)累积排放量分别增加了14.0%和6.4%,各处理间差异显著(P<0.05)。不同还田方式下土壤CO_(2)排放速率与土壤温度、土壤含水量进行单因素模型拟合,均呈二次函数相关关系,且达到了显著水平(P<0.05),土壤温度和土壤含水量分别解释68.2%—73.7%和21.3%—82.8%的土壤CO_(2)排放速率变化,但土壤温度和土壤含水量的双因素复合模型能更好地解释土壤CO_(2)排放速率的变化,解释度达到78.5%—82.8%。相关性分析表明,土壤CO_(2)累积排放量与速效钾、微生物量碳呈极显著相关关系(P<0.01),与土壤有机质、碱解氮、全氮和pH呈显著的相关关系(P<0.05)。秸秆还田处理下土壤碳平衡均为正值,为大气CO_(2)碳汇。SH处理下土壤碳平衡和固碳潜力显著高于QH、FG处理,提高幅度分别为23.4%、475.7%和7.1%、30.7%(P<0.05),表现出较强的碳汇功能。在两年收获期,秸秆还田显著提高了玉米产量,其中SH处理最高,但与QH和FG处理间无显著差异。【结论】本试验条件下,综合考虑固碳减排效应和产量,3种秸秆还田方式相比,秸秆深层还田(SH)是一种较好的还田方式。 展开更多
关键词 秸秆还田方式 土壤CO_(2)排放 土壤温度 土壤含水量 玉米产量 碳平衡
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