南京包山式城墙典型病害及整体坍塌预警分析

南京城墙作为现存的世界第一城垣，对其安全性进行科学评估尤为重要。包山式城墙为南京城墙的主要形式之一，由于其与土体相连，受力特点不同于常规的自承重城墙。本研究整理了包山式城墙的6种典型病害，并提出了包山式城墙的数值建模方法，将其简化为城墙-粘结界面-土体的模型。利用ABAQUS软件，结合工程实例模拟土坡强度折减后包山式城墙的鼓胀。研究结果表明：随着土体的强度下降，包山式城墙的位移不断增大形成鼓胀现象，最终发生倾覆坍塌，可通过墙体底部拉应力-顶点位移曲线中的明显拐点确立监测变形预警值；在此基础上，讨论土坡高度对整体坍塌的影响，并给出放坡角度的合理取值；城墙底部的积水浸泡会导致底部强度折减进而发生相对错动，可通过底部墙体达到极限抗拉强度时的最大相对位移确立监测变形预警值。最后，提出了包山式城墙的修缮保护建议。     

"The very model of modern urban decay": outsiders' narratives of industry and urban decline in Gary, Indiana

In the eyes of many, the steel city of Gary, Indiana, entered a period of decline in the middle of the twentieth century. The once great city was seemingly racked by job loss, crime, racial division, or moral decay. Which of these caused the decline of the city depended upon the perspective of the story's teller. Each narrative of decline contained a different moment where the city went wrong and it began to decay. For some it was the moral decay of the 1950s, for others it was the rise of black power and politics in the 1960s, for still others it was the white backlash against civil rights in the 1970s. Some saw a microcosm of America, some saw a dangerous cauldron of race and ethnicity. The source of decline and the origins of the urban crisis were largely in the eye of the beholder. The stories people chose to tell about Gary mattered because for much of the twentieth century, Gary was at the center of American narratives about industrialism. These were outsider narratives of decline read onto the Indiana steel city because Gary represented larger debates. People read onto Gary their changing expectations and anxieties about industry and industrial spaces. This article traces the changing attitudes outsiders held toward Gary from the middle of the twentieth century through the period of deindustrialization at the end of the century and examines American narratives about deindustrialization and urban decline.     

南京市住宅价格时空分异格局及其影响因素分析——基于地理加权回归模型的实证研究

以2009-2017年南京市“一主三副”商品房社区为基本研究单元,运用GIS地统计分析中的普通Kriging插值法对“一主三副”住宅价格空间分布进行模拟和估计,并利用地理加权回归（GWR）模型探究社区属性、商业区位、交通区位、服务区位和景观区位等类型变量对住宅价格的影响规律。研究结果表明：①南京市房价总体上呈现主城向副城递减的中心外围模式,“一主三副”住宅价格空间结构呈现出同心圆和扇形融合的混合模型。②中心位势对主城住宅价格影响相对下降,对副城影响相对提升,交通位势表现出相反的趋势,住宅房龄、绿化环境对住宅价格的影响由主城向副城递减,山水景观的影响由长江沿岸向外围递减。③主副城住宅价格影响因素具有空间异质性,其中主城受距CBD距离、住宅建筑年代和绿化率的影响较大,而副城主要受距地铁站距离、距景观资源距离的影响。     

Adjusting to change: privilege and place in post-Soviet central Moscow

In the new Russia where one lives plays an important part in influencing life chances, and consequently in shaping opinions regarding the changes since the collapse of the Soviet system in 1991. This study of the social geography of central Moscow is based on surveys of sample populations undertaken in 1993 and 1997. Post-Soviet central Moscow has undergone substantial change in population, social class structure and economic function during the transition from socialism to a market economy. Tens of thousands of central city residents have been relocated in the wake of re-development in the central city and there is evidence of growing social stratification as the inherent high value of central city space is reflected in the post-Soviet market place. Quality of life indicators suggest that there remains a wide gap between expectations raised by the advent of democracy and the market economy and the reality of daily life and labour for central city residents.     

城：夏商时期对自然资源的控制问题

本文主要从中心——周边系统相互关系的角度探讨了晋南地区两个商城的政治经济活动,特别是跨地域的控制和运输重要自然资源的问题,并认为聚落形态的变化尤其是城的兴衰,应从政治、经济系统的角度考察。在中国早期国家发展阶段,政治中心从周边地区掠取重要自然资源战略的改变,往往会影响人口的移动和城市的兴衰。     

矿业城市生命周期与空间结构演进规律研究

在对矿业经济和城市发展生命周期判定的基础上,选取石油城市大庆、有色金属城市金昌、煤炭城市大同等典型矿业城市作为研究样本,梳理矿业城市发展生命周期,重点研究矿业城市空间结构有序化演进的一般规律。文章认为矿业城市经历"矿业经济-新型制造业-综合性"的完整发展过程,城市空间结构对应整体演进过程也呈现出"矿业经济的点状离散-新型制造业的分区极化-综合性城市的多组团圈层"的阶段性特征。在矿业经济时期内部又呈现"导入期、成长期、成熟期、衰退期/转型期",且对应不同阶段在城市人口、职能、经济结构等方面均呈现不同的特点。矿业城市空间演进整体上体现出"矿业经济是空间发展的初期主导,空间结构随城市职能的升级而演变,空间作用呈现集聚与分散的交替"的有序化发展规律。     

Origin and Collapse of Complex Societies in Oaxaca (Mexico): Evaluating the Era from 1965 to the Present

I summarize recent archaeological work in Oaxaca, Mexico, with a focus on questions central to world prehistory: the origin and collapse of complex societies. Monte Albán was the capital of an emerging civilization in the southern highlands of Mexico during the second half of the first millennium B.C. Soon after the foundation of the ancient city, there is evidence for state formation and a political expansion into regions outside the Valley of Oaxaca. Centuries later, Monte Albán went into decline, giving way to the competing small polities found throughout Oaxaca at the time of the Spanish conquest. Since the late 1960s, our knowledge of these changes has been transformed by study of Oaxaca's pre–Monte Albán past, regional settlement surveys, and processual model building. Evolutionary and historical perspectives allow for significant refinement of current debates surrounding the rise and fall of complex societies in Oaxaca.     

The changing landscapes of Southwest Montréal: a visual account

The Canadian inner city is currently marked by diversity and dynamism. One way to approach this diversity is through photography. A visual approach was used to capture the simultaneous upgrading, decline/revitalization, decline and stability within the changing landscapes of Southwest Montréal, Canada's original industrial heartland.     

Explaining recent fertility increase in Central Asia

After a swift decline during the 1990s following the collapse of the Soviet Union, period fertility rates have either been stagnating or increasing in all countries of Central Asia. In this paper, I investigate the role of data artifacts, population composition effect, economic context and shifting tempo effect in explaining fertility changes in Central Asia. The analysis is primarily based on comparison of fertility data from the vital registration system with estimates from other data sources. The results show that the recent changes to be real and not a result of data artifact. The most plausible explanations are to be found in the three other non-exclusive factors (population composition effect, economic context and shifting tempo effect) that contributed jointly and simultaneously to push up the period fertility rates in the region.     

Siena in the early Middle Ages: new data from the excavation at Santa Maria della Scala

The data from excavations around the hospital of Santa Maria in Siena help to build a picture of the city in the early Middle Ages. Comparison is made with the rural site of Montarrenti, and significant differences between the economic development in the town and country are observed, although both suffered decline. Settlement, and economic activity in the city of Siena are seen to go into recession in the post‐Roman period, but signs of growth become visible from the ninth century onwards.     

What makes people stay in or leave shrinking cities? An empirical study from Portugal

The attractiveness of cities as places to live determines population movements into or out of them. Understanding the appealing features is fundamental to local governments, particularly for cities facing population decline. Pull and push attributes can include economic aspects, the availability of amenities and psychological constructs, initiating a discussion around which factors are more relevant for migration. However, such discussion has been underexplored in studies of shrinking cities. In the present study, we contribute to the discussion by identifying pull and push factors in Portuguese shrinking cities. Data were collected using a face-to-face questionnaire of 701 residents in four shrinking cities: Oporto, Barreiro, Peso da Régua and Moura. Factor analysis and automatic linear modelling were used to analyse the data. Our results show that the economic activity is the most relevant feature for retaining residents. However, characteristics specific to each city, related to heritage and natural beauty, are also shown to influence a city’s attractiveness. The cause of population shrinkage was also found to influence residents’ assessments of the pull and push attributes of each city. Furthermore, the results show the relevance of social ties and of place attachment to inhabitants’ intention to continue living in their city of residence.     

桃渚城城墙病害初步调研与保护对策探讨

临海桃渚城建于明代,是浙江保存最完好的抗倭卫所城址,全国重点文物保护单位。通过对桃渚城的现存状况进行调查分析可知,城墙目前存在局部垮塌、鼓闪、灰浆流失等病害,其本身的构造缺陷加上降雨和植物生长的共同作用是病害的主要成因。这类问题在东南沿海地区的古城墙中具有一定普遍性。针对这些病害以及桃渚城的构造特点,结合国内一些城墙保护的工程实例,提出桃渚城的保护策略:加强墙体的结构稳定性、加固墙芯填土、增设墙顶防水措施、及时疏改威胁本体安全的植物,可为后续以及同类城墙的保护工作提供参考。     

Hunting intensification and the Hohokam “collapse”

The role of long-term demographic stress in the “collapse” of the Hohokam culture of southern Arizona is an open question. If chronic imbalances between population levels and food production, as opposed to catastrophic events, were key factors in the population decline of the 15th century, then the archaeological record should produce evidence for resource stress prior to the near-abandonment of the region. It is difficult to document resource depression in archaeofaunas from southern Arizona, however, because they are dominated by small game throughout the agricultural sequence. Furthermore, in an ecologically and economically diverse region, it is difficult to apply data from an individual site to a region-wide phenomenon like the Hohokam demographic decline. This study uses data from 85 faunal assemblages to explore hunting strategies from the earliest agricultural villages to the cessation of archaeologically visible occupation of the region. One means of hunting intensification employed by the Hohokam was to diversify beyond a focus on staple rabbit species, through the use of fish, birds, artiodactyls, and smaller terrestrial game. Diversification is measured in this study through evenness indices. These indices suggest that demographic stress was increasing in the dense population centers of the Salt and Gila River basins prior to the “collapse.”     

Chapels and chantries in late medieval and early modern Besançon: the record book of Jean Ferreux,chaplain

During the fifteenth-century reform of the Poor Clares by St. Colette, many new convents were built in France and Flanders. Their chapels were endowed by local benefactors with perpetual chantries. Much later, a diligent chaplain in Besançon reviewed the state of the chantries entrusted to his care. His record describes their condition after a decline of over two centuries, owing to currency devaluation, the collapse of the local aristocracy, and the nuns' neglect of their duties. The chaplain's book shows that these chantries, though founded in perpetuity, maintained their original function for only a few years. After that, even as the benefactors were themselves forgotten, so their chantries slowly fell into disrepair and decline.     

The Italian government's response to the problem of Jewish refugees 1945–1948∗

This article deals with the fall of Palestinian-Arab Jaffa in the 1948 war. As the largest Arab city in Palestine, its accelerated social and military collapse came as a surprise to many, despite Jewish dominance in the Jaffa region. While previous research has mostly neglected this question, the present study aims at revealing the underlying causes, besides Jewish military pressure, for Jaffa's collapse and the resulting exodus of its Arab population. The article describes the precarious social and military Palestinian-Arab situation in Jaffa as a case study for Palestine as a whole during the December 1947–May 1948 inter-communal war.     

The Iron Bridge at Sunderland: A Revision

Abstract

The rapid expansion and subsequent collapse of the local brick and tile industry in the American Midwest between 1870 and 1910 is one of the most striking episodes in the industrial history of the United States. This study draws largely on local material to detail this expansion and collapse in a four county area of Central Illinois. Between 1870 and 1910 eighty commercial brick and tile works were established. Most remained in production for less than twenty years. Today only one, Diller Brothers in Chatsworth, continues in business. This paper describes the rise and fall of this industry, examining its origin, locational pattern, methods of operation, structures, decline, and impact on the present landscape.     

SPATIAL DIFFERENTIATION OF POPULATION DEVELOPMENT IN A DECLINING REGION: THE CASE OF SAARLAND

We increasingly understand the causes of population decline: these can be, among others, processes of deindustrialization, decreasing fertility or the succession of a city through the stages of urban life as the city matures. However, we are still insufficiently able to explain why differences still exist between cities within regions experiencing the same macro‐processes and between cities of the same “level of maturity”. This research addresses this intra‐regional differentiation in population development in the declining former mining region of Saarland (Germany). Quantitative and qualitative analysis reveals that the differentiation in current decline stems from (1) the differentiated population development trajectories of the past, with a massive population boom followed by an aged and declining population in the industrial municipalities; and (2) the spatial distribution of amenities over the region; and (3) the spatial distribution and accessibility of housing opportunities steering migration flows. The latter are not necessarily concentrated in those areas that are attractive. Rather, the distribution of these housing opportunities strictly follows the planning logic of the supra‐local institutional framework, with a concentration of housing within easy access of major transportation infrastructure and in larger centres. The case study thus reveals that the mechanisms behind this intraregional differentiation are much more complex than often portrayed in the urban development and decline debate.     

五代宋元时期古都长安商业的兴衰演变

与汉唐时期相比 ,五代、宋、元时期古都长安的市场格局、商业面貌等方面都发生了显著变化 ,其中最突出的变化表现在 :长安的市场逐渐由以前封闭型的市场而演变为开放型的市场。这一变化不论在经济史上还是在中国城市发展史上都具有重要的意义。五代、宋、元时期 ,长安商业的兴衰演变大致可以划分为四个时期 :(一 )唐末到北宋初 ,长安商业处于严重萧条期 ;(二 )宋真宗以后至北宋末 ,是长安商业显著恢复和发展期 ;(三 )金朝至元初 ,长安商业陷入徘徊不前的状态 ;(四 )元初到元末 ,长安商业有一定的恢复和发展。本文还对以上四个时期长安商业的兴衰状况及原因作了进一步分析。     

The decline and shifting geography of violence in Russia’s North Caucasus, 2010-2016

Abstract

A spatial analysis of the geography of insurgency in the North Caucasus of Russia from 1999 through the end of 2016, focused on the period since 2010, corroborates other work on the incidence of violence in the region. A sharp drop in the absolute number of conflict events over the past half-decade occurred as violence diffused from Chechnya in the mid-2000s and is attributable to a range of domestic and international factors. Domestically, the decline is broadly linked to the securitization of the region around the 2014 Winter Olympics in Sochi, the return to the use of the Kremlin power vertical as a system of political management after an interlude focused on economic development as a mitigation strategy, and the wider adoption of harsh management tactics at the regional and republic scales. Internationally, potential insurgents have left Russia to fight in the Middle East and Ukraine. Using a conflict-event data-set (N = 18,960) from August 1999 through the end of 2016 and focusing on the period since the creation of the North Caucasus Federal District in January 2010, the paper identifies a set of notable trends within the decline and shift in violence. Key findings include a percentage increase in arrests carried out by Russian security services, a decline in retaliation across conflict actors, and the failure of federal subsidies to contribute to declines in violence in the region. The long-term prospects for continued insurgency in the North Caucasus, specifically in light of the collapse of the Islamic State and Russia’s domestic challenges, remain uncertain and should acknowledge the recent decline in violence in the region.     

Past,present and future revitalization trends in Canadian mid-size city downtowns

The article is a critical review of the literature investigating the impact suburbanization has had since the mid-20th century on the downtowns of Canadian mid-size cities and the strategies deployed to revitalize these districts. It demonstrates that large city downtowns are more likely than their mid-size city counterparts to enjoy conditions favourable to their success, hence the need to devise revitalization efforts tailored to the reality of mid-size city downtowns. The article identifies revitalization strategies adopted over the last decades, which mostly failed to reverse the decline affecting these downtowns. It then concentrates on the present, and likely enduring, revitalization model, which emphasizes hospitality, recreation, culture, services, and walkability. The article refines the understanding of the differences between mid-size and large city downtowns by concentrating on their specific dynamics and explores future revitalization options for mid-size city downtowns. It discusses the present and likely enduring absence of alternatives to the present revitalization model and highlights its equity downsides as it challenges the downtown low-income resident living environment.