Comparative Analysis of Metro Passengers’Mobility Patterns and Jobs-housing Balance of Metropolitan

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.

Balance control during gait initiation: State-of-the-art and research perspectives

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.

China＇s Sovereign Balance Sheet and Its Risk Assessment

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.

Spatial and Temporal Patterns of Supply and Demand Balance of Water Supply Services in the Dongjiang Lake Basin and Its Beneficiary Areas

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.

CFD simulation of spontaneous coal combustion in irregular patterns of goaf with multiple points of leaking air

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.

The foundation of “The Max Area Pattern” and Its Training Significance

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.

Area-Efficient Low Power CMOS Image Sensor Readout Circuit with Fixed Pattern Noise Cancellation

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...

新疆北部城市碳排放时空分异与碳平衡分区

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。

面向时空轨迹流的共同运动模式分布式挖掘算法

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。

NFV场景下基于协议和目的端口的负载均衡策略

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。

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

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。

“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

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。

优质均衡视域下新优质学校的价值意蕴和实践样态

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。

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

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。

舒兰教授基于“平衡脏腑”“证症结合”思想论治儿童抽动障碍

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。

Analysis on the Spatio-temporal Patterns of Water Conservation Services in Beijing

The shortage of water resources is a key factor limiting the sustainable development of the economy and society in Beijing. This study analysed the spatiotemporal patterns of Beijing’s water conservation services(WCS) based on the water balance equation at multiple scales, including city, main functional areas and key districts and counties, determined the differences in the water conservation amount among different land cover types and investigated the reasons for the spatiotemporal differences in the water conservation amount. The results indicated that:(1) compared to 2005, water conservation amount increased substantially in 2010. However, the overall water conservation capacity was low.(2) Among the various land cover types in Beijing, the average water conservation capacity decreased in the following order: wetland, forest, grassland, cropland, bare land and artificial surface.(3) The average water conservation amount in the main functional areas of Beijing varied substantially and was positive only in the ecological conservation area(ECA).(4) The water conservation capacity of each district and county varied substantially within ECA, among which the contribution of the forest in Miyun District, Huairou District and Pinggu District was the highest. The changes in the spatiotemporal patterns of Beijing’s WCS were the synthetic effects of changes in the land covers and meteorological conditions. This study is helpful in achieving the sustainable utilization of water resources in Beijing.

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

【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。

肌力平衡:释义、内在机制及实践应用

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。

数字经济如何重塑我国区域创新格局?——基于研发要素流动的视角

本文基于新经济地理学“中心—外围”理论,从研发要素流动的视角,深入分析数字经济重塑区域创新格局的内在机理,并采用2011—2021年我国285个城市面板数据,实证考察区域创新格局的演变趋势,以及数字经济对区域创新格局的重塑效应。研究表明,考察期内我国区域创新存在收敛趋势,即区域创新格局趋于均衡;数字经济有利于缩小区域间创新差距,改善区域创新格局的非均衡状态。上述结论在更换不同权重矩阵、替换不同度量指标、考虑滞后效应以及剔除异常样本点后依然具有稳健性。机制检验结果表明,数字经济通过影响研发要素流动,改善区域创新格局非均衡状态,并促进区域均衡创新格局的形成。本文研究结论为深化数字经济改革,优化区域创新格局提供政策启示。

低蛋白日粮不同氨基酸平衡模式对藏香猪生产性能、肉品质的影响

为探究低蛋白质(LP)日粮不同氨基酸(AA)平衡模式对藏香猪生产性能、肉品质的影响,选取4月龄健康藏香猪36头,按照平均体重接近的原则,随机分为3组,每组3个栏,每个栏4头猪,分别饲喂藏香猪肉氨基酸比例日粮(TPM组)、中国NYT 2004地方猪氨基酸比例日粮(NYT组)、美国NRC 2012猪营养氨基酸比例日粮(NRC组)。结果表明:(1)NYT组、NRC组的末体重较TPM组分别提高35.60%、46.92%(P <0.05),平均日增重较TPM组分别提高74.77%、98.45%(P <0.05),平均日采食量较TPM组分别提高8.19%、22.72%(P <0.05),料重比较TPM组分别降低37.64%、38.15%(P <0.05)。(2)NYT组、NRC组的胴体重较TPM组分别提高54.40%、94.97%(P <0.05),眼肌面积较TPM组分别提高78.70%、118.70%(P <0.05),屠宰率较TPM组分别提高13.81%、30.51%(P <0.05)。(3)NRC组熟肉率较TPM组提高7.75%,肉色b降低22.46%(P <0.05)。(4)NRC组肌肉中辛酸、十三酸、花生酸、二十四碳酸、棕榈油酸、十七碳酸、芥酸、神经酸、二十二碳六烯酸含量较TPM组提高66.66%、85.71%、50.00%、50.00%、200.00%、32.54%、37.68%、100.00%、33.33%(P <0.05),而棕榈酸、二十三碳酸、外周血红细胞膜脂肪酸、二十碳三烯酸含量较TPM组降低33.33%、33.33%、51.08%、14.86%(P <0.05),NYT组、NRC组共轭亚麻酸较TPM组提高13.66%、19.43%(P <0.05),γ-亚麻酸较TPM组降低11.80%、10.07%(P <0.05),α-亚麻酸较TPM组降低20.54%、17.07%(P <0.05)。(5)NYT组精氨酸、谷氨酸、甘氨酸、丙氨酸含量含较TPM组降低18.04%、27.94%、19.23%、21.30%(P <0.05),而组氨酸含量较TPM组提高57.83%(P <0.05)。(6)NRC组粗蛋白质、粗脂肪、中性洗涤纤维、钙表观消化率较TPM组提高32.75%、3.09%、20.40%、10.94%(P <0.05)。综上,日粮低蛋白条件下,与TPM组和NYT组日粮氨基酸比例相比,NRC组日粮氨基酸比例能够显著提高藏香猪生产性能和肉品质、营养表观消化率,是最佳氨基酸平衡模式。