Effects of disparity distribution on visual comfort for multiple objects of stereoscopic images

With the development of stereoscopic technology, more attention is attracted on the stereoscopic three-dimensional(S3 D) content and service, and researches on images and videos have emerged in large numbers. This paper focuses mainly on visual comfort affected by characteristics of disparity for multiple objects. To find the relationship between disparity distribution and visual comfort perception, several subject evaluation experiments are done. The study contains two spatial distribution types of disparity: 1) only one of the foreground objects has zero disparity; 2) one of the foreground objects has positive disparity, while the other one has negative disparity. The experimental results and relative regression analysis provide appropriate relationship between disparity distribution and visual comfort for both conditions, which is significant to meet the applicant field in S3 D content acquisition, display adjustment and quality evaluation.

Regional disparities of phytoplankton in relation to different water masses in the Northwest Pacific Ocean during the spring and summer of 2017

The West Pacific Ocean is considered as the provenance center of global marine life and has the highest species diversity of numerous marine taxa.The phytoplankton,as the primary producer at the base of the food chain,effects on climate change,fish resources as well as the entire ecosystem.However,there are few large-scale surveys covering several currents with different hydrographic characteristics.This study aimed to explore the relationships between the spatio-temporal variation in phytoplankton community structure and different water masses.A total of 630 water samples and 90 net samples of phytoplankton were collected at 45 stations in the Northwest Pacific Ocean(21.0°–42.0°N,118.0°–156.0°E)during spring and summer 2017.A total of 281 phytoplankton taxa(>5μm)belonging to 61 genera were identified in the study area.The distribution pattern of the phytoplankton community differed significantly both spatially and temporally.The average abundances of phytoplankton in spring and summer were 797.07×10~2 cells/L and 84.94×10~2 cells/L,respectively.Whether in spring or summer,the maximum abundance always appeared in the northern transition region affected by the Oyashio Current,where nutrients were abundant and diatoms dominated the phytoplankton community;whereas the phytoplankton abundance was very low in the oligotrophic Kuroshio region,and the proportion of dinoflagellates in total abundance increased significantly.The horizontal distribution of phytoplankton abundance increased from low to high latitudes,which was consistent with the trend of nutrient distributions,but contrary to that of water temperature and salinity.In the northern area affected by the Oyashio Current,the phytoplankton abundance was mainly concentrated in the upper 30 m of water column,while the maximum abundance often occurred at depths of 50–75 m in the south-central area affected by the Kuroshio Current.Pearson correlation and redundancy analysis(RDA)showed that phytoplankton abundance was significant negatively correlated with temperature and salinity,but positively correlated with nutrient concentration.The phytoplankton community structure was mainly determined by nutrient availability,especially the N:P ratio.

Regional disparities of phytoplankton in relation to environmental factors in the western Arctic Ocean during summer of 2010

Global warming has caused Arctic sea ice to rapidly retreat,which is affecting phytoplankton,the primary producers at the base of the food chain,as well as the entire ecosystem.However,few studies with large spatial scales related to the Arctic Basin at high latitude have been conducted.This study aimed to investigate the relationship between changes in phytoplankton community structure and ice conditions.Fifty surface and 41 vertically stratified water samples from the western Arctic Ocean（67.0°–88°26′N,152°–178°54′W） were collected by the Chinese icebreaker R/V Xuelong from July 20 to August 30,2010 during China＇s fourth Arctic expedition.Using these samples,the species composition,spatial distribution,and regional disparities of phytoplankton during different stages of ice melt were assessed.A total of 157 phytoplankton taxa（〉5 μm） belonging to 69 genera were identified in the study area.The most abundant species were Navicula pelagica and Thalassiosira nordenskioeldii,accounting for 31.23% and 14.12% of the total phytoplankton abundance,respectively.The average abundance during the departure trip and the return trip were 797.07×10~2 cells/L and 84.94×10~2 cells/L,respectively.The highest abundance was observed at Sta.R09 in the north of Herald Shoal,where Navicula pelagica was the dominant species accounting for 59.42% of the abundance.The vertical distribution of phytoplankton abundance displayed regional differences,and the maximum abundances were confined to the lower layers of the euphotic zone near the layers of the halocline,thermocline,and nutricline.The species abundance of phytoplankton decreased from the low-latitude shelf to the high-latitude basin on both the departure and return trips.The phytoplankton community structure in the shallow continental shelf changed markedly during different stages of ice melt,and there was shift in dominant species from centric to pennate diatoms.Results of canonical correspondence analysis（CCA） showed that there were two distinct communities of phytoplankton in the western Arctic Ocean,and water temperature,ice coverage and silicate concentration were the most important environmental factors affecting phytoplankton distribution in the surveyed sea.These findings will help predict the responses of phytoplankton to the rapid melting of Arctic sea ice.

Physical Growth Pattern of Settlements in a Traditional Region, Southwest Nigeria

The study examined the growth pattern of settlements in Oke-Ogun area of Oyo State, Nigeria between 1984 and 2011;and predicted the future growth pattern of settlements in the study area. Both primary and secondary data were used for this study. Primary sources of data include Global Positioning System (GPS), Landsat TM and ETM+ imageries of 1984, 1990, 2000, and 2011. Secondary data included administrative map and population data of the study area. Descriptive statistics and geospatial technique were used to analyse the data collected. The results showed a random pattern of settlement distribution in the study area. Results revealed that settlements covered about 0.52% of the total land area in 1984;1.32% in 2000;and 3.78% in 2011. Whereas linear pattern of growth characterised the periods between 1984 and 1990;clustering, infilling, and fringes were the patterns of growth that characterised the periods between 1990 and 2011. The study predicted that, at an average 1.2% of annual growth rate, settlements will occupy about 44.37% of the total land area by 2031. The study concluded that settlements in the study area varied in the patterns of distribution;the area was dominated by indigenous settlements type with overconcentration of social and economic infrastructures in few centres.

脱贫地区农户非农化生计转型的共同富裕效应

基于共享发展理念,从农户非农化生计转型及其对农村收入分配格局的影响视角,探讨了脱贫地区巩固脱贫成果、实现共同富裕的路径,并利用2021年甘肃省16村1302户调查数据进行了实证分析。研究发现:脱贫地区农户非农化生计转型促进了家庭资源由低效率部门向高效率部门的配置,提高了农户收入水平并抑制了农村内部收入差距的扩大,具有“帕累托改进”性质;通过分位数回归进一步证实,非农化生计转型对收入差距的抑制是通过提高低收入家庭资源配置水平和收入水平、改善农村收入分配格局实现的;通过细分生计类型发现,务工生计对改善收入分配格局的贡献最大,其次为兼业和非农经营生计;进一步分析发现脱贫地区农户非农化生计转型对农业转型的带动作用不强,以传统农业生计为主的农户家庭收入水平较低,是当前农村收入差距形成的主要原因之一。基于以上结论从农户生计转型视角提出了脱贫地区优化收入分配格局、实现共同富裕的政策建议。

中国共同富裕水平的测度、动态演进和地区差异分析

基于公平与效率维度构建指标体系,运用熵值法测度2011—2021年中国省域共同富裕水平,分析其空间自相关性,并通过核密度估计方法刻画其分布动态,采用Dagum基尼系数分析其空间差异。研究发现,全国及四大地区的共同富裕水平均显著提升,西部增幅最大;考察期内全国空间集聚效应显著;东部地区共同富裕发展不均衡问题最凸显;地区间差异呈缩小态势,但仍是总体差异的主要来源。

Role of Selective Interaction in Wealth Distribution

In our simplified description‘wealth’is money(m).A kinetic theory of a gas like model of money is investigated where two agents interact(trade)selectively and exchange some amount of money between them so that sum of their money is unchanged and thus total money of all the agents remains conserved.The probability distributions of individual money(P(m)vs.m)is seen to be influenced by certain ways of selective interactions.The distributions shift away from Boltzmann-Gibbs like the exponential distribution,and in some cases distributions emerge with power law tails known as Pareto’s law(P(m)/m−(1+®)).The power law is also observed in some other closely related conserved and discrete models.A discussion is provided with numerical support to obtain insight into the emergence of power laws in such models.

中国居民收入的地区差距与分布动态演进趋势

居民收入差距问题是共同富裕进程中需要关注的重点问题。基于2014—2020年中国居民收入省级数据,直观展示中国居民收入的基本特征和空间格局,深入解析中国居民收入的地区差距与分布动态演进趋势。研究发现,中国居民收入空间分布不均衡,呈现“东高西低、南北倒U型”的分布态势;基尼系数双维分解结果表明,居民收入地区差距总体呈收敛趋势,区域间的工资性收入差距是地区差距的主要来源。Kernel密度估计和Markov链分析结果表明,中国居民收入增长势头强劲,相邻省份间存在正空间相关性。研究结论为新时期有的放矢缩小居民收入差距、推动区域协调发展提供理论支撑,对于改善居民收入分配格局、扎实推动共同富裕具有一定参考价值。

长江经济带局部城市收缩、发展分异与空间作用机理探讨

局部城市收缩对长江经济带可持续发展带来一定影响。以长江经济带110个城市为研究对象,基于2000—2020年人口普查数据,甄别长江经济带收缩城市,并分析收缩城市与非收缩城市的发展分异,进一步地基于“中心—外围”范式,利用交通时长数据,探讨不同区位城市收缩的空间作用机理,其结论显示:(1)2010—2020年长江经济带有51个收缩城市,其中26个延续了自2000年以来的人口负增长趋势;(2)收缩城市在人口年龄结构、教育结构,以及产业结构、公共服务等方面,与非收缩城市出现系统性差异,伴随人口选择性流失,长江经济带局部城市收缩可能形成了除东中西和城乡以外的另一种区域差距的类型,即收缩城市与非收缩城市的发展分异;(3)与中心城市的相对区位非线性地影响城市规模:与中心城市的最短交通时间小于50分钟的城市,倾向于实现人口正增长,大于50分钟的城市人口增长率呈非线性变化,更容易出现城市收缩。基于上述结论,有关方面应当优化长江经济带城市体系,加强长江经济带多式联运交通路网建设,引导长江经济带收缩城市合理地“瘦身健体”,从而推进长江经济带整体可持续发展。

我国产业数字化水平的地区差异与分布动态演进

文章在构建产业数字化评价指标体系的基础上,运用熵权法和线性加权法相结合的方法准确测度我国整体及四大经济区产业数字化水平,运用Kernel密度估计、Dagum基尼系数探究我国省级层面产业数字化的分布动态演进和地区差异。结果显示:整体上,全国及各地区产业数字化水平呈逐年上升趋势,但是各地区之间存在较大差距,且存在一定的发散趋势;全国产业数字化水平总体差异呈不断增大趋势,差异来源贡献度表现为“区域间差异最大,区域内差异次之,超变密度最小”;中西部地区存在明显的极化现象。

旅游业高质量发展能否促进共同富裕?

实现共同富裕是社会主义的本质要求,也是中国式现代化的重要特征。本文聚焦旅游业高质量发展与共同富裕两大发展战略的内在联系,旨在探讨旅游业高质量发展能否促进共同富裕,并利用2011—2019年的省级面板数据进行实证检验。研究发现:(1)旅游业高质量发展不仅能够显著促进共同富裕,还能提升富裕度,即实现“做大蛋糕”,但仅当旅游业高质量发展水平越过一定门槛后才更利于“分好蛋糕”,同时旅游业高质量发展对于共同富裕水平、富裕度以及共同度水平处于中间层的省份更有利;(2)旅游业高质量发展对共同富裕以及富裕度的正向效应呈现出“中部>西部>东部”的影响态势,东北部现阶段未显现出影响效果,而对于共同度而言,仅在中西部呈现正向效应,且“中部>西部”,在东部地区则扩大了差距;(3)对外开放和城镇化水平会影响旅游业高质量发展对于共同富裕的影响程度。基于此得出结论:应进一步提升旅游业高质量发展水平,促进社会整体收入水平的提高,改善收入分配,从而推动共同富裕的实现。

我国服务业碳排放全要素生产率增长的地区差异、动态演进及影响因素研究

本文以服务业为研究对象,采用共同前沿、Dagum基尼系数和Kernel密度估计方法探讨了碳排放约束下我国服务业全要素生产率增长的地区差异、动态演进和影响因素等问题。研究发现,我国服务业碳排放全要素生产率增长存在显著的地区差异特征,总体差距的主要来源是超变密度,其次是地区内差异,地区间差异的贡献率最低。我国服务业碳排放全要素生产率增长存在不同极化特征和“俱乐部收敛”趋势。服务业碳排放全要素生产率增长支持“环境库兹涅茨曲线”假说,外商直接投资对服务业碳排放全要素生产率增长的作用表现为正向不显著,能源消费结构对服务业碳排放全要素生产率增长的影响显著为负,行业结构的转型升级显著促进了服务业碳排放全要素生产率的提高。本文的研究对于识别不同区域之间服务业碳排放全要素生产率的增长差异,实现服务业绿色高质量发展具有一定的现实意义。

舞毒蛾研究进展

舞毒蛾是农林业上的重要害虫,具有食性杂、危害重、分布广、幼虫随风移动等特点。该文综述了近年来舞毒蛾在国内外的研究进展,对舞毒蛾在形态特征、分布及危害、防治措施、外界胁迫、寄主病毒等方面进行归纳总结,以期为同领域深入研究提供参考。

基于遥感与GIS的中国农村居民点规模分布特征

利用 2 0 0 0年TM图像判读的中国土地利用矢量图提取全国农村居民点信息 ,分析了中国农村规模分布的基本特征。中国农村居民点密度呈现地带性差异 ,东部地区农村居民点密度较高 ,西部较低。农村居民点规模区域差异明显 ,北方大于南方 ,平原地区大于丘陵地区 ,经济发达地区大于经济欠发达地区 ;全国农村居民点规模较小 ,平均规模越小的地区集中在规模较小的居民点较多。全国农村居民点分布不均匀 ,孔隙度指数与农村居民点密度相关程度较高 ,农村居民点密度较高的地区 ,孔隙度指数较小 ,农村居民点分布较为均匀 ,距离较低 ;农村居民点密度较小的地区 ,孙隙度指数较大 ,农村居民点分布不均匀 ,距离较远。

亚洲型舞毒蛾在北美的适生性

采用DYMEX V2.0软件和ArcGIS分析工具相结合的方法,提出亚洲型舞毒蛾Lymantria dispar(L.)的DYMEX参数指标体系和适生性评判标准,分析亚洲型舞毒蛾在北美的适生范围与适生程度。研究表明,加拿大的南部、美国的大部分地区以及墨西哥中南部极少部分区域为该虫的适生区。研究结果将为国家植物保护部门提供有关亚洲型舞毒蛾的植物检疫决策支持。

中国农村地区收入差距解释:1997～2005

1997～2005年我国农村地区收入差距以2000年为转折点,经历了先下降后上升的变化过程。要素分解分析表明,1997～2000年地区收入差距的下降完全归因于分配效应;2001～2005年地区收入差距的上升主要归因于结构效应。样本分解分析表明,东中西部地区间的差距和东部地区内部的差距是形成农村地区差距的主要原因。费景汉-兰尼斯分解分析表明,工资性收入、地理位置、教育、物质资本和人均占有耕地面积共解释了地区收入差距的80%以上。

近20年来中国区域经济发展差异的测定与评价

选取人均GDP、人均社会消费零售总额社会经济指标,通过计算其变异系数、加权变异系数、威廉森系数、最大与最小系数,对中国1978—2002年的经济发展不平衡性进行了动态时序分析,定量评价了近20年来中国区域社会经济发展的差异程度;采用经济区位熵指标分析了中国经济发展空间格局的动态演化过程。结果表明,1990年以前中国经济区域差异程度在减小,1990年以后经济区域差异程度扩大,社会消费水平总体上呈扩大趋势。在空间格局上,经济发达区由过去的东北地区扩展到东部沿海地区,1970—1980年代区域差异表现为经济发达区、经济发展区、经济落后区之间的差异,而到1990年代主要表现为经济发达区和经济落后区之间的差异,两极化趋势明显,区域差异程度加大。

行业垄断的收入分配效应——对城镇垄断部门的实证分析

垄断行业借助于政府赋予的垄断权力,长期获取较其他行业更高的收入和利润,导致了垄断与非垄断行业间收入分配差距的不断扩大及居民收入不平等程度的不断提高。通过对垄断行业收入分配状况的分解计算,考察垄断与非垄断行业之间及其内部的收入分配效应并提出合理的应对措施,已成为中国收入分配领域的当务之急。

共同富裕的概念辨析、面临挑战及路径探索

党的十九届六中全会审议通过的《中共中央关于党的百年奋斗重大成就和历史经验的决议》提出:坚持发展为了人民、发展依靠人民、发展成果由人民共享,坚定不移走全体人民共同富裕道路。本文通过对共同富裕概念的多角度辨析,明确共同富裕是全体人民的富裕,但并不意味着绝对平均主义。在此基础上,进一步阐述现阶段中国实现共同富裕的基础,认为目前依然面临居民整体收入水平不高、收入差距较大、基本公共服务均等化程度略低、分配制度不够合理等挑战。实现共同富裕,要依靠解放和发展生产力来夯实物质基础,以实施乡村振兴战略来缩小城乡差距,以推进区域协调发展战略来缩小区域差距,以完善收入分配制度来促进收入分配公平。

1990—2010年云南省少数民族人口分布空间差异分析

收集整理了云南省第四、五、六次少数民族人口普查数据,创建了1990,2000,2010年GIS数据集,采用探索性空间数据分析(ESDA)的全局和局部空间自相关分析方法,对县域全局和局部空间差异的变化趋势、特征与成因进行了初步探索。结果表明:(1)20年中,云南省少数民族人口分布具有显著的空间正相关性,但随着产业结构的调整以及就业人员的再分配,其空间相关性在逐步降低。(2)2000—2010年的10年内,云南省少数民族人口分布出现了在局部区域内显著聚集且增加的现象,主要集中在滇东南地区,而且表现出了一定的扩散效应。(3)随着云南省少数民族地区社会、经济的发展,少数民族区域人口分布空间差异有可能会进一步扩大。