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1.
This article examines corporate services from a regional perspective, using the concept of “spatial divisions of labor.” We examine non-routine, control-related activity as well as routine activity, bridging the literatures on white- and pink-collar work. Using the Geographic Profile on Employment and Unemployment, published by the U.S. Department of Labor, we examine occupational data across the nine census divisions continuously from 1983 through 1988. This data source is unique because it reports on occupational data annually, in relatively disaggregate form, and does so by geographic regions. Location quotients for the occupational data serve to identify a “core” with respect to concentrations of control-related activity. This core comprises the New England, Middle Atlantic, and Pacific divisions. In contrast, routine activity generally is more dispersed, although some regional separation is evident for specific occupations, showing regional concentration in subordinate or “peripheral” regions. The results of the study identify regional patterns, which are heuristically valuable in raising questions regarding the complex processes responsible for spatial divisions of labor. In particular, the findings suggest a geography of modes of production, a subject that requires substantially more attention.  相似文献   

2.
线上教学被赋予了重要的历史使命,发挥了重要的作用,但是师生不能面对面直接交流导致情感交互不够,企业现场实践缺失。因此,为确保疫情防控时期“食品质量管理”课程的教学质量和效果,通过开设“新冠疫情和食品质量安全”“食品人战疫故事”“食品工厂云参观”及“家庭厨房烹饪危害分析与质量控制”等板块,探索了线上教学与课程思政资源的融合并进行了实践,以期为食品专业其他课程的课程思政改革提供参考。  相似文献   

3.
There has been significant research undertaken examining the “creative class” thesis within the context of the locational preferences of creative workers. However, relatively little attention has been given to the locational preferences of creative companies within the same context. This paper reports on research conducted to qualitatively analyse the location decision making of companies in two creative sectors: media and computer games. We address the role of the so‐called “hard” and “soft” factors in company location decision making within the context of the creative class thesis, which suggests that company location is primarily determined by “soft” factors rather than “hard” factors. The study focuses upon “core” creative industries in the media and computer game sectors and utilises interview data with company managers and key elite actors in the sector to investigate the foregoing questions. The results show that “hard” factors are of primary importance for the location decision making in the sectors analysed, but that “soft” factors play quite an important role when “hard” factors are satisfactory in more than one competing city‐region.  相似文献   

4.
Global economic activity is networked through cross‐national linkages between firm headquarters, branches, and subsidiaries. Brokerage emerges as a key territorial function of this network, with some places acting as gateways or intermediaries for flows of global knowledge, information, or trade. This function is particularly salient for small states and territories leveraging the benefits of borrowed size by offering global professional services, warehousing, logistics, shipping, and finance to wealthy nations or high net individuals. Nonetheless, to date our understanding of how small states and territories facilitate wealth accumulation is limited to broad concepts of their role as “gateways” or “brokers.” Drawing on a typology of brokerage and a network analysis applied to the ties between approximately 700,000 firm headquarter and subsidiary locations of 13 of the world's largest stock exchanges, we explore the brokerage role of small states and territories through case studies of Luxembourg, Singapore, Hong Kong, and Panama. Brokerage is found to play an important role in the economy of all four. We argue that each of these small states and territories is uniquely positioned as a broker in global corporate networks, but that this role differs according to geo‐economic and political positionality.  相似文献   

5.
为了给用户提供可信的信息服务,需要对网络信息进行可信度评估,而评价网站可信度的方法是网络信息可信度评估的基础和重要组成部分,旨在探索农业综合型和专业型网站可信度评估的方法。应用模糊综合评价法对提出的网站可信度评估指标体系中的重要指标数据进行了融合,再以涉及油菜信息的网站为试验对象,进行试验数据采集与分析,对43个包含油菜信息的综合型和专业型网站可信度进行了计算和综合排序。试验Ⅰ选取了网站PR值、反向链接数、Alexa排名、页面收录数等4个指标,试验Ⅱ选取了网站PR值、反向链接数、Alexa排名、页面收录数、专业性等5个指标,分别进行模糊综合评价。试验结果表明：从网站综合实力判断网站可信度,农博网、中国农业信息网、一亩田油菜网、中华人民共和国农业部、中国农业科学院网对评评价指标体系Ⅰ反应较好;整体上国家级网站可信度高于地方级网站;网站可信度与当地的信息化和农业水平有一定关系;专业型网站与综合型网站差距较大。从网站综合实力和专业需求两方面判断网站可信度,较好的有农博网、中国农业信息网、中华人民共和国农业部。试验Ⅰ的评测指标适合于综合型网站可信度量,试验Ⅱ的评测指标适合于专业型网站可信度量。该文提出的网站可信度评价模型可为其他网站可信度评估提供参考,其中的指标可根据实际情况来选取以及确定其权重。  相似文献   

6.
梅丽 《作物杂志》2022,38(6):14-5
藜麦营养全面,植株转色后花色艳丽,观赏期长达40d左右,且耐旱、耐寒,是一种集多功能为一体的新兴保健食粮。北京市自2015年引种藜麦,在适宜种植区、适宜品种筛选、营养品质检测、抗逆稳产栽培技术探索、菜品开发和技术示范等方面开展了大量工作。北京藜麦适应性栽培研究表明,藜麦在海拔≥300m、年均气温≤12.5℃、年均积温≤4802.0℃·d、年均光照强度≥2268.7lx的区域可正常成熟;“陇藜1号”、“陇藜3号”、“红藜1号”和“红藜2号”4个品种表现优良;藜麦米富含蛋白质,特别是“红藜1号”和“红藜2号”蛋白含量高达19.6%~20.0%;围绕栽培、农机、植保三大关键环节集成的藜麦抗逆稳产栽培技术体系在京郊示范应用面积为453.33hm2,应用率达100%;与一茬籽粒玉米相比,藜麦增收3.77万元/hm2。但区域发展不平衡、生产效率低和没有享受政策性农业保险等因素制约了藜麦在北京的持续健康发展。今后,应从加大政策和财政支持、提高藜麦机械化生产水平及建立健全相关标准制度等方面着手,做大做强北京藜麦产业,让藜麦的“小生产”能够在“大市场”中找到“微需求”,卖出好价钱。  相似文献   

7.
The purpose of this study was to investigate how Taiwanese high‐tech firms' foreign direct investment (FDI) leads to agglomeration and competition among cities in China. By using social network analysis to analyze 1,111 subsidiaries affiliated with 270 multinational corporations (MNCs) during the years between 1988 and 2006 in 30 major Chinese cities, this study finds that: 1) agglomeration in Chinese cities falls into three primary categories: the hub cluster, the communication‐extended cluster, and the computer‐extended cluster. Among the aforementioned clusters, the hub cluster is the most critical in terms of firm location, and therefore is often a high‐priority investment site for Taiwanese high‐tech firms. 2) Chinese cities fall into four primary groups, or “blocks”: the core block, the coast block, the inland block, and the periphery block; these groups were determined by applying a structural equivalence analysis of which members of each type are in competition with one another. By linking the findings of the urban network characteristics to Chinese regional economic policies, this study provides guidance to aid executives in determining the optimal location for future FDI. Implications and suggestions for host country governments in terms of firms' investment strategies are also discussed.  相似文献   

8.
Wild emmer wheat, Triticum turgidum subsp. dicoccoides, (2n = 4× = 28; genome BBAA), the progenitor of domesticated wheat, is genetically closely related to durum and common wheat. This wild taxon has characteristics that would be valuable if transferred to domesticated wheat. A series of chromosome-arm substitution lines (CASLs) of wild emmer wheat were produced in the background of an Israeli common wheat cultivar. These CASLs were evaluated in a pot experiment and in field trials in Israel and California for their grain yield (GY) and its components and for grain protein percentage. In addition, the extent of genetic interactions (epistatic effects) between “wild” and “domesticated” alleles, within and between homoeologous groups 1 and 7 as expressed in grain and protein yields and other quantitative traits, were determined. The research has shown that wild emmer wheat harbors genetic variability for quantitative traits and that the “wild” genes interact among themselves in a non-additive way in the common genetic background. Several chromosome arms improve GY and protein percentage in common wheat, but their effects will be presumably enhanced when combination of genes from several “wild” arms are integrated into a single “domesticated” genotype. Hence, the interaction between these genes and those in the recipient common wheat must be accounted for when higher yield or protein content is desired. The results of this study indicate on the potential of this material for breeding and genetic analysis, and support the idea of pyramiding genes from a wild species.  相似文献   

9.
“姜”及其相关植物的原植物考   总被引：1，自引：1，他引：0  
为研究中国古籍文献中记载的“姜”以及与“姜”有关植物的科学名称以及分类学,从有文字记载的历史文献开始,逐一整理出在不同历史时期典型文献中出现的“姜”,利用植物分类学的方法,结合比较形态学的分析方法,确定了“姜”的原植物为姜科姜属的Zingiber officinale Roscoe。同时,整理出与“姜”有关的植物10种,涉及到名称12个,确定了其中8种植物的原植物的科学名称。对“姜”及其相关植物的原植物的考证,以案例分析的方式,将今论古,对历史典籍中记载的“姜”进行分类学研究,并认为尽管中国先民没有建立起完整的现代植物分类学体系,但是对植物的认识依然非常清晰、明确,并确定中国先民早在北魏时期就已经掌握了用无性繁殖的方式繁育“姜”的方法。  相似文献   

10.
The effects of water and salt stress on rate of germination and seedling growth were investigated under laboratory conditions in 46 soya bean genotypes from Central-West region of Brazil to verify how these stresses may limit crop establishment during the initial growth stage and also to identify the most tolerant genotypes to drought and salinity. Mild water and salt stresses were imposed by seed exposure to –0.20 MPa iso-osmotic solutions with polyethylene glycol—PEG 6000 (119.57 g/L) or NaCl (2.357 g/L) for 12 days at 25°C. The germination percentage, seedling length and seedling dry matter were measured, and then, salt or drought tolerance indexes were calculated. The “NS 5909 RG,” “NS 7000 IPRO,” “NS 7338IPRO,” “FPS Solimões RR,” “NS 5151 IPRO,” “SYN 13610 IPRO,” “LG 60177 IPRO,” “NS 6909 IPRO” and “BMX Desafio RR” were identified as the most drought-tolerant genotypes, whereas under salinity conditions, the genotypes “5D 615 RR,” “BMX Desafio RR,” “5D 6215 IPRO” and “BMX Ponta IPRO” were identified as tolerant. The “BMX Desafio RR” is the genotype most adapted to both stress conditions and, therefore, should be used under conditions of water shortage and excess salt in the soil at sowing time.  相似文献   

11.
ABSTRACT Novelists Wendell Berry and Edward Abbey consider the natural world in a way most or their predecessors did not: the land itself as a complex character which deserves the respect of its human inhabitants. “Cultivating Wilderness” presents an overview or this relationship in Abbey's and Berry's fiction relating not only how the authors contrast characters attuned to the land and its patterns with others who arc “out of sync” with the natural world, but also how both ferry and Abbey deal with the interaction or human and natural communities—especially in a “modern world” which seemingly prefers to control nature and eradicate mystery. While it is not the role of fiction to offer blueprints for economic, environmental, or social policies, the novels and short stories of Wendell Berry and Ed Abbey do address important issues and eloquently call for a new paradigm for human behavior—at individual, community, and national levels—within and toward the natural world. I felt, rather than knew, with a sudden keen taste and appetite, what it was to be a farmer in Islandia. I sensed the absorbing interest of the immediate task that also is integrated with rill the other tasks of one's life into a rounded whole, because one's land und one's farm is larger than oneself, reaching from a past long before one began into a future long after one is dead—but all of it one's own.  相似文献   

12.
Societies in many developed nations around the world are aging. Over the past decade, a growing body of research has emerged internationally in an effort to anticipate and prepare for the transport challenges posed by this unprecedented demographic change. This paper contributes to this line of research by offering new insights into senior travel behavior focusing on the recent Canadian experience. Using weekday data from the 1992 and 2005 General Social Surveys on time use, changes in the number of trips, the duration of trips, trip mode, and trip timing are evaluated for urban seniors. In contrast to the experiences of many other developed nations, analysis of the first three indicators of behavioral change refutes the notion that “automobility” has increased in Canada over the 13‐year period. While this finding is encouraging, it is tempered by the fact that Canadian seniors who choose to travel by car are doing so increasingly during the morning and evening peak periods. The results from a peak versus non‐peak departure‐time model that pools data from both years offer important insights into factors driving this change. For instance, the results suggest that the propensity to start a trip during rush hour has increased over time for non‐work trip purposes.  相似文献   

13.
农民教育是社会主义新农村建设的核心问题。培养一大批用得上、留得住、掌握一定专业知识的新型农民，农民教育是关键。由大学和地方政府科技部门共同实施的“沈阳市农村青年科技人才研修工程”， 探索出“政府出资、大学培训、农民受益” 的科技培养新模式，搭建了科技培训平台，为社会主义新农村建设培养出一大批“懂技术、善经营、留得住、用得上”的新型农民，已产生了很好的经济效益和社会效益，是解决“三农”问题的一大创举。  相似文献   

14.
为了科学、准确地对农业气象服务效益进行评估和分析,结合威武市当地农业气象服务的特点,利用AHP（层次分析法）与BCG（波士顿矩阵）相结合的方法,将复杂的效益评估系统数学化、层次化、系统化,构建适合当地特色的新型农业气象服务效益评估模型,结合2015年武威市农业气象服务满意度调查问卷进行效益评估。结果表明,“气象部门对当地农业气象需求的了解程度与带来的社会和经济效益”、“预报要素准确率”、“气象服务产品特性”、“农业气象产品内容丰富性”等4类指标属于核心类项目,成为农气象服务中产生良好社会和经济效益的主要指标项目,“用户未来打算”属于发展型项目,具有良好的发展潜力。此次评估结果,能够使气象部门合理确定服务产品重点、改进服务内容,积极拓宽服务信息发布渠道,有效分配农业气象服务资源,对提高农业气象防灾减灾水平有着重要意义。  相似文献   

15.
This study examines the evolutionary geography of British Columbia's forest industries during a period marked by volatility and decline. Conceptually, the study draws upon the industrial life cycle model, identifying the distinctive characteristics of resource industries during the transition to maturity and beyond. Empirically, the study focuses on industry population dynamics and employment change at a meso‐scale, to reveal changing organizational, industrial, and geographical structures of BC's forest industries during the study period. There are high levels of plant exits and in some sub‐industries also of entry, a decline in large integrated firms, and important shifts in core‐periphery characteristics.  相似文献   

16.
The article addresses the embeddedness of automotive production in Poland in terms of supply networks. A comprehensive analysis of more than 550 suppliers, supported by company interviews, shows that foreign‐owned producers become embedded in Poland in the automotive supplier networks they have largely created themselves. Numerous local suppliers gain access to export markets and become integrated in a Europe‐wide production system. This trend has been accompanied by significant upgrading of foreign affiliates and domestic firms in terms of product quality, cost efficiency, adaptability, and fast response, but far less in nonproduction competences such as R&D. It is argued that the competences of automotive suppliers in Poland are built upon the localized capabilities, which are a product of the dynamic interplay between the activity of foreign firms and the changing local environment comprising various stakeholders. The localized capabilities constitute elements of a company's sunk costs and are embedding automotive producers in Poland. At the same time, the dependence on decisions and innovations from abroad and the limited development of local design and brands may constrain the future role of suppliers from the semiperipheral economy of Poland.  相似文献   

17.
ABSTRACT It is often assumed that future urban employment will be increasingly dependent on the knowledge‐intensive business services (KIBS). This underpins much of the current thinking about the development of the English “core cites.” Their example is employed to examine the more general validity of such assumptions, in terms of five critical questions to which research offers only partial and indefinite answers. For any city, how far are these activities really “knowledge intensive”? What markets do they serve? Is their future growth certain? And even when this is the case, how can they make a long‐term contribution to local urban economic success? Finally, how far do urban economic institutions and policies need to be adapted to foster knowledge‐based activities such as KIBS? It seems that, despite the growth of measured KIBS employment, most of the core cities possess few truly knowledge‐intensive KIBS, capable of serving national and international business markets, competitively adapting to future change, and adding to the competitiveness of the wider urban economy. Nationally such activities remain focused into the London region where, if anything, they have increased their concentration is recent years.  相似文献   

18.
陕西关中蚂蚱麦和山西平遥小白麦是我国北方小麦品种的原始骨干亲本,解析蚂蚱麦和小白麦及其衍生系的遗传多样性对于小麦品种改良具有重要的参考意义。本研究利用小麦660KSNP芯片对蚂蚱麦、小白麦及其衍生品种(系)进行全基因组扫描,分析其遗传多样性。结果表明,小麦3个基因组的多态性SNP标记数为BAD,第4同源群的多态性标记数最少, 149份供试材料基因多样性(H)范围为0.095～0.500,平均值为0.336;核苷酸多样性指数(π)范围为0.272～0.435,平均值为0.340;而遗传相似系数(GS)变幅为0.335～0.997,平均值达0.619,表明蚂蚱麦和小白麦衍生系的遗传多样性较低。聚类分析表明蚂蚱麦和小白麦紧密地聚在亚群I,其衍生品种(系)分为5个亚群,其中2000年以前以蚂蚱麦或小白麦的单一衍生系为主,分在亚群I、II、III, 2000年以后多数品种同时拥有蚂蚱麦和小白麦血缘,分在亚群IV、V,遗传多样性较高,且与大面积推广品种聚为一类。因此,应加强优异基因资源导入,拓宽小麦品种的遗传基础,最终提高育种水平。  相似文献   

19.
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20.
Over the past decades, the automotive sector in China has been characterized by the obligation of foreign manufacturers to enter joint ventures, transfer technologies, and localize production. Still, the Chinese automotive industry has remained dependent on foreign brands, capital, and technology. The advent of markets and supply chains for electric vehicles, however, changes the framework conditions for established foreign automotive firms in terms of competitive landscape and access to core technology components. This is mainly the result of political initiatives: Established automotive manufacturers are exposed to direct and indirect restrictions that influence their production of electric vehicles, their choice of suppliers, and their potential market shares in the future. This paper outlines multilevel bargaining processes of Chinese and foreign actors as they aim to maximize value capture in a fundamentally transitioning automotive sector. In contrast to the lead firm-centric focus of recent global production networks (GPN)-discussions, this paper argues that the determinants of how production networks evolve is first and foremost a question of the institutional environment. Focusing on power balances between state and firm actors in multilevel bargaining processes offers a way of explaining GPN-evolution in institutional contexts in which power concentrates in executive bodies and decision-making processes are often informal.  相似文献   

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