A city and national metric measuring isolation from the global market for food security assessment

The World Bank has invested in infrastructure in developing countries for decades. This investment aims to reduce the isolation of markets, reducing both seasonality and variability in food availability and food prices. Here we combine city market price data, global distance to port, and country infrastructure data to create a new Isolation Index for countries and cities around the world. Our index quantifies the isolation of a city from the global market. We demonstrate that an index built at the country level can be applied at a sub-national level to quantify city isolation. In doing so, we offer policy makers with an alternative metric to assess food insecurity. We compare our isolation index with other indices and economic data found in the literature. We show that our Index measures economic isolation regardless of economic stability using correlation and analysis.     

1998—2016年中国省际网络联系结构特征

基于中国省级行政区之间铁路货流数据（不含港澳台）,采用社会网络分析及GIS空间分析等对1998—2016年中国省际网络联系结构特征进行分析。结果表明：① 1998—2016年中国铁路货流网络密度呈先增长后下降的趋势;② 中部地区和环渤海经济圈的省份在铁路货流网络中货运量处于领先地位,沿海省份之间铁路货运联系减弱;③ 山西和内蒙古在铁路货流网络中占有重要地位,而海南、西藏则在铁路货流网络中处于边缘地位;④ 广东密切联系华中地区和西南地区,西北省份相互联系及对外联系都较弱;⑤ 铁路货流网络中地域邻近性与经济联系很大程度上决定了凝聚子群的构成,随着中国经济发展和铁路货运的不断变化,铁路货流网络的凝聚子群增多,规模变小。     

Improving Coal Quality Estimations with Geostatistics and Geophysical Logs

In most modern coal mines, there are many coal quality parameters that are measured on samples taken from boreholes. These data are used to generate spatial models of the coal quality parameters, typically using inverse distance as an interpolation method. At the same time, downhole geophysical logging of numerous additional boreholes is used to measure various physical properties but no coal quality samples are taken. The work presented in this paper uses two of the most important coal quality variables—ash and volatile matter—and assesses the efficacy of using a number of geostatistical interpolation methods to improve the accuracy of the interpolated models, including the use of auxiliary variables from geophysical logs. A multivariate spatial statistical analysis of ash, volatile matter and several auxiliary variables is used to establish a co-regionalization model that relates all of the variables as manifestations of an underlying geological characteristic. A case study of a coal mine in Queensland, Australia, is used to compare the interpolation methods of inverse distance to ordinary kriging, universal kriging, co-kriging, regression kriging and kriging with an external drift. The relative merits of these six methods are compared using the mean error and the root mean square error as measures of bias and accuracy. The study demonstrates that there is significant opportunity to improve the estimations of coal quality when using kriging with an external drift. The results show that when using the depth of a sample as an external drift variable there is a significant improvement in the accuracy of estimation for volatile matter, and when using wireline density logs as the drift variable there is improvement in the estimation of the in situ ash. The economic benefit of these findings is that cheaper proxies for coal quality parameters can significantly increase data density and the quality of estimations.

     

煤炭富集区开发模式解析——以锡林郭勒盟为例

近年来我国煤炭资源富集区的开发力度空前加大,目前已经初步形成了煤炭—火电—煤化工一体化开发的态势。然而,煤炭资源富集区大多生态脆弱、水资源短缺,这一开发模式与区域主导生态功能存在尖锐冲突。重点剖析了内蒙古锡林郭勒盟煤、电、煤化工发展中存在的问题,认为突出表现在以下几个方面,即现有开发模式的可持续性较差、生态和景观破坏严重、水资源供需矛盾突出、生态建设具有盲目性。要实现资源开发与生态保护的协调发展,就必须调整区域开发模式,控制资源开发范围,加大生态建设投入,并探索适用的生态建设模式。从长远来看,要实现煤炭资源富集区的可持续发展,应通过国土规划明确区域功能定位,建立规范的生态补偿机制,编制综合性区域开发规划,并加强矿区生态恢复技术研究。     

Geostatistical space–time mapping of house prices using Bayesian maximum entropy

Mapping spatial processes at a small scale is a challenge when observed data are not abundant. The article examines the residential housing market in Fort Worth, Texas, and builds price indices at the inter- and intra-neighborhood levels. To accomplish our objectives, we initially model price variability in the joint space–time continuum. We then use geostatistics to predict and map monthly housing prices across the area of interest over a period of 4 years. For this analysis, we introduce the Bayesian maximum entropy (BME) method into real estate research. We use BME because it rigorously integrates uncertain or secondary soft data, which are needed to build the price indices. The soft data in our analysis are property tax values, which are plentiful, publicly available, and highly correlated with transaction prices. The results demonstrate how the use of the soft data provides the ability to map house prices within a small areal unit such as a subdivision or neighborhood.     

Application of time-lapse digital imagery for ground-truth verification of satellite indices in the boreal forests of Alaska

Satellite remote sensing studies of snow cover in high-latitude boreal forests require ground-truth verification based on ground observation networks. In this study, we used time-lapse digital images to precisely detect the extent of snow cover at nine locations in the boreal forests of Alaska, and to demonstrate the relationship of these ground-truth measurements to satellite indices of snow cover. Our results show that normalized difference vegetation indices (NDVIs) and normalized difference water indices (NDWIs) show significant variations at the end and beginning periods of continuous snow cover: the NDVIs on the last days of continuous snow cover ranged from 0.12 to 0.37, and those on the first days of continuous snow cover ranged from 0.16 to 0.38. The normalized difference snow indices (NDSIs) were also positive during periods of continuous snow cover and negative during periods of no snow cover. The NDWIs varied significantly from the beginning to the end of periods of continuous snow cover. This study confirms that continuous snow cover is important for accurate phenological studies using NDVIs in the region of the trans-Alaska camera network. Simple cameras can be effectively utilized in ground-based networks, functioning not only as a ground-truth verification tools for calibrating satellite indices, but also as a source of data to fill data gaps in satellite records.     

Pricing Weather Derivatives Index based on Temperature: The Case of Bahir Dar,Ethiopia

In this paper we present a stochastic model for daily average temperature to calculate the temperature indices upon which temperature-based derivatives are written. We propose a seasonal mean and volatility model that describes the daily average temperature behavior using the mean-reverting Ornstein-Uhlenbeck process. We also use higher order continuous-time autoregressive process with lag 3 for modeling the time evolution of the temperatures after removing trend and seasonality. Our model is fitted to 11 years of data recorded, in the period 1 January 2005 to 31 December 2015, Bahir Dar, Ethiopia, obtained from Ethiopia National Meteorological Services Agency. The analytical approximation formulas are used to price heating degree days (HDD) and cooling degree days (CDD) futures. The suggested model is analytically tractable for derivation of explicit prices for CDD and HDD futures and option. The price of the CDD future is calculated, using analytical approximation formulas. Numerical examples are presented to indicate the accuracy of the method. The results show that our model performs better to predict CDD indices.     

居住环境剥夺测度及其对房价的影响——以兰州市为例

小区是居民日常生活和构建社会关系的重要场所,由于居住环境差异,导致剥夺现象发生。为探究居住环境剥夺对房价的作用机制,构建居住环境剥夺测度体系,创新了居住环境剥夺指数计算方法,运用混合地理加权回归模型和地理探测器分析居住环境剥夺与房价的关系。结果表明：（1） 兰州市平均房价为12566.93元·m^-2,空间上呈现出多核心、组团式分布格局,表现为从核心向外逐级递减的趋势。（2） 基于6个维度服务设施数量和种类差异,居住环境剥夺也呈现出不同空间分布格局。（3） 所有服务剥夺均与房价呈负相关,教育服务剥夺对房价影响力最强,生活服务剥夺对房价影响力最弱,教育和交通服务剥夺交互作用对房价解释力最强。研究结果对促进资源配置公平和城市健康快速发展至关重要。     

Long-Term Appreciation of Owner-Occupied Single-Family House Prices in Milwaukee Neighborhoods

Annual price indices of owner-occupied single-family houses are estimated for 111 neighborhoods in Milwaukee, Wisconsin, for the period of 1971-1993 using hedonic price methods controlling for quality differences across housing units. The rates of price appreciation vary significantly from neighborhood to neighborhood. During the 22-year study period, nominal house prices in some neighborhoods increased more than 500%, whereas those in others decreased. In general, the neighborhoods close to each other exhibit similar price movements. In some cases, however, there are sharp differences between the neighborhoods when strong boundaries, such as a river or an expressway, exist between them even though the physical distance between them is small. Poor neighborhoods generally have experienced low appreciation rates, although the racial composition and the crime rate in the neighborhood seem to contribute the differential as well.     

基于POI大数据的沈阳市住宅与零售业空间关联分析

城市住宅及其价格与区域商服业的空间关联性量化研究是人文-经济地理学的重要研究内容。以辽宁省沈阳市为案例,以住宅和零售业兴趣点（Point of Interest, POI）为数据源,基于空间核密度分析提取住宅和各类零售业的空间聚类形态,量化表达商住空间布局的相关性,并在此基础上运用地统计方法测算房价的空间异质性及其与零售业态空间布局的差异特征。结果表明,零售业的整体空间聚集特征与住宅相似,呈现中心城区块状聚集、外围城区多中心离散的分布格局;零售业与住宅核密度相关系数为0.95,超市、便利店等小规模的零售业与住宅密度相关性较强,商场商厦的聚集效应落后于城市住宅,大型零售业应该在铁西经济技术开发区等住宅密集区规划选址,为居民提供高端购物服务;住宅价格的倒“U”型空间分布模式与零售业空间密度的圈层衰减特征相符。     

Institutions, the governance of quality and on-farm value retention for Indonesian specialty coffee

Fluctuating global commodity prices affect the livelihoods of millions of tropical farmers worldwide. In recent years, systemic oversupply of many tropical agricultural products, grown in countries such as Indonesia, has meant that agricultural incomes have continuously fallen below subsistence levels. Within an increasingly open global trade regime, along with the limited ability of governments to protect domestic farm prices, quality-informed product differentiation appears to offer an escape route from the trap of low commodity prices. However, ownership and governance of quality constructions are fundamental to determining who benefits from such differentiation. This paper examines the use of geographical identities as a specific tool for value-adding in agricultural produce, presenting the case of specialty coffee production in South Sulawesi, Indonesia. The potential for producer-driven geographical indications compete with corporate-driven quality constructions, where the latter are able to appropriate place-related quality associations by using trademarks, vertical integration and tightly coordinated supply chain controls. An emergent politic of quality governance and ownership in global commodity chains reveals the highly restricted institutional terrain within which growers of specialty coffee might attempt to retain a higher share of the economic rent associated with quality production.     

“被高铁”现象的理性分析——以京沪高铁为例

近年来,中国高铁步入快速建设期,而高铁建设的重要目的之一就是客货分流。高铁客运专线的建设大大地提升了客运能力,从而可以释放既有线路的运输能力于货物运输。但是高铁客运的票价也高于既有线路,同时由于普通列车车次的减少,使得居民出行可能要被迫选择票价更高的高铁,这种现象称作“被高铁”。本文对媒体关注的“被高铁”现象进行了理性分析,以京沪高铁沿线城市为例,根据2015年1月1日列车时刻表数据计算出的时间节省的货币成本与小时工资(时间价值)作比较,并结合高铁车次比重,计算了不同城市的居民“被高铁”的可能性。研究发现：①很多“城市对”之间都存在时间节省的货币成本高于小时工资的情况,“被高铁”现象较为普遍;②“被高铁”的可能性在50%左右;③各城市“被高铁”的程度有较大差异,京沪高铁沿线城市的“被高铁程度”整体呈现出“两头低,中段高,长三角相对较低”的特征。研究认为,虽然从目前来看,京沪高铁沿线城市的普通列车班次减少不明显,但如果进行较大幅度调整,很多低收入旅客出行时可能会被迫选择高铁,并将带来负面的社会影响。本文的理性分析可为列车班次的调整方案提供参考。     

北京市住房价格和租金的空间分异与相互关系

当前中国住房销售市场、住房租赁市场发展不平衡,研究住房价格、租金的空间分异与相互关系,对建立“租售并举”的住房制度具有重要参考价值。利用2016年北京市各住宅小区的住房价格、租金数据,及2006—2016年北京市逐月住房销售价格指数、住房租赁价格指数,从时空尺度剖析了住房价格、租金的空间分异与相互关系,并剖析了背后的差异机制。结果表明：① 北京市住房价格和租金的空间格局均呈多中心圈层递减结构,且南北差异明显,但租金的空间分异程度弱于住房价格。② 住房价格具有中等程度的空间相关性,受政策等随机性因素影响相对较大,而租金具有强烈的空间相关性,受区位交通等确定性因素影响相对较大。③ 住房价格和租金的价格剖面线并不相同,住房价格易受学区、大型公园等的影响,而租金更易受就业所在地、建筑年龄等的影响。售租比呈混乱斑驳、相对均质的扁平化分布特征,且小区越高档,售租比越高。④ 北京市住房销售市场和住房租赁市场基本相对独立发展,更符合双重市场的特征。产生上述差异的主要原因在于住房销售市场和住房租赁市场的市场特征、服务人群以及市场发育程度不同。     

长江中下游夏季降水变化与亚洲夏季风系统的关系

以长江中下游流域实测降水数据和亚洲季风指数为基础,采用Mann-Kendall检验、线性相关和偏相关分析、小波分析等方法,揭示长江中下游夏季降水的时空变化特征及其与亚洲季风系统之间的相互关系和影响差异。结果表明,近50 a来长江中下游夏季降水量呈显著的增加趋势,其与亚洲主要夏季风指数之间均呈负的线性相关关系,且显著性影响范围东亚夏季风大于南海夏季风大于南亚夏季风。不同亚洲夏季风子系统间存在复杂的相互作用关系,尤其是东亚夏季风和南海夏季风之间的相互作用对长江中下游夏季降水产生了重要影响。长江中下游夏季降水量与亚洲主要夏季风指数存在2~4 a时间尺度上的显著相关性,且以反位相关系为主。此外,长江中下游夏季降水量与东亚夏季风的相干性最为突出,在小于8 a的时间尺度上,两者之间的相关性在近50 a来呈现减弱的趋势,特别是自20世纪80年代中后期以来。     

基于灰色关联模型对江苏省PM2.5浓度影响因素的分析

采用克里金插值法分析2014年江苏省PM_2.5浓度空间分布特征,运用灰色关联模型计算PM_2.5浓度与影响因素间关联度,分析主要影响指标因子与PM_2.5浓度空间分布的相互关系。结果显示：① 江苏省PM_2.5浓度具有沿海低、内陆高,南部高、北部低的空间分布特征;② PM_2.5污染来源指标层的权重值最大（w_i = 0.4691）,空气质量与气象要素指标层的权重稍大（w_i = 0.2866）,城市化与产业结构层的权重值最小（w_i = 0.2453）;③ 在27个指标因子中,与PM_2.5浓度关联度为中度的仅有公路客运量、房屋建筑施工面积、园林绿地面积、人口密度等4个指标因子,PM_2.5与其余指标因子均呈强度相关联,其中与PM₁₀、O₃、降雨量、公路货运总量、地区工业总产值和第二产业占地区生产总值比重等指标的关联度较高;④ PM_2.5污染源指标层与PM_2.5浓度关联度值较大的城市分别是南京、无锡、常州、南通、泰州市;城市化与产业结构指标层与PM_2.5浓度关联度值较大的城市分别是徐州、苏州、盐城、常州市;空气质量与气象要素指标层与PM_2.5浓度关联度值较大的城市分别是盐城、扬州、常州、南通市。综合分析可知,影响指标因子关联度值与PM_2.5浓度空间分布有较好相关性。研究表明,灰色关联模型可有效分析影响PM_2.5浓度的主要因素,能对PM_2.5浓度影响指标进行定量分析与评价。     

Concordance of interannual variability in ice regime of Baikal and lake Ladoga

We examine the dependence of the ice conditions for two major lakes of Asia and Europe: Baikal and Ladoga, on regional values of the arithmetic sums of mean daily winter air temperatures and global atmospheric processes expressed by atmospheric circulation indices. By ranking the winters according to the sums of mean daily winter air temperatures, it was possible to identify winters of the same type of severity for the regions of Baikal and Ladoga. The winters of the same type show an enhancement in correlations between ice characteristics with respect to the sums of winter air temperatures and atmospheric circulation indices as well as ice characteristics of the two lakes. It is shown that the interannual changers in characteristics of ice regime of Ladoga and Baikal are largely determined by the same atmospheric processes. The role of the circulation is most clearly manifested in variation of temperature regime indicators. Thus, the sums of air temperatures accumulated during a winter in the regions of these lakes show primarily the closest correlation with the Arctic and North Atlantic oscillation indices.     

利用高支链类异戊二烯(HBIs)重建极地海冰的研究进展

海冰的准确重建对反演气候和环境变化具有重要意义。近期研究表明,有机指标高支链类异戊二烯(HBIs)具有重建极地海冰状况的潜质,海洋沉积物中具有海冰特异性的单烯HBI(IP_(25))和双烯HBI(IPSO_(25))指标已分别成为研究北极和南极海冰变化的有力工具。本文综述了IP_(25)、IPSO_(25)的提出和验证,分析了影响HBIs生成、迁移和埋藏的诸多因素,总结了为实现精细化区分海冰状况和定量化重建海冰密集度而提出的新指标的发展及应用,并就目前存在的问题和未来研究方向进行了探讨和展望。     

Modernization of the industrial complex from the perspective of the concept of production cycle (A case study of Kuznetsk coal use)

An economic-geographical analysis is made of the main current problems with the development of Kuzbass implying a strict dependence of the economy on world prices and demand for coal, a high transportation component in the price of Kuznetsk coal, and on the irrational structure of the region’s coal sector. From the perspective of the market economy, N. N. Kolosovskii’s concept of energy-production cycles is rethought, the notion of the “coal production cycle” is formulated, and a generalized scheme of this cycle is presented. This study revealed the territorial limits of Kuznetsk coal exports and use which formed the basis for determining the near concentrated consumption of coals including Kemerovo oblast and neighboring regions of Western Siberia. For this zone the proposals were developed for a modernization of the structure of coal production cycle including recommendations for the extraction of coal and associated components, their alternative exports and primary and downstream processing. Attention is focused on the economic-geographical substantiation of the specific location of enterprises for downstream processing of Kuznetsk coals including the facilities for coking, semicoking, generator and subsurface gasification, hydrogenization as well as transportation of coal via the Kuzbass–Ural coal pipeline.     

Dynamics of the subsistence minimum on discomfort territories of East Siberia

An analysis is made of the decline in the quality of life of the population in municipal districts of East Siberia under conditions of climatic and socioeconomic discomfort. The study revealed a correlation between the low subsistence level of the northern territories and the increase in the ratio of mortality/birthrate indices. We suggest a technique for calculating the subsistence level having regard to the degree of climatic discomfort and the poor transport infrastructure.