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ABSTRACT Container shipping lines are well aware of the growing importance of global production networks. While continuing to focus on improving the fundamentals, many shipping lines have developed a keen interest in other segments of the logistics and transportation market to offer integrated and worldwide services to global production networks. This paper aims to assess the overall level of freight integration in thirty‐four shipping lines, and provides an insight into the extent to which freight integration serves as a business model in liner shipping. The results point to a great variety and range of freight integration in the shipping business. Each carrier leverages its service portfolio to develop specific capabilities. There is clearly no single best strategy for the whole liner shipping industry to serve global production networks. 相似文献
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Luis Suarez‐Villa 《Growth and change》2003,34(4):390-414
ABSTRACT The e‐economy is part of a larger phenomenon, technocapitalism, that is transforming business organizations and the ways in which they transact, produce, and ship their goods. Technocapitalism is an evolution of market capitalism that is rooted in technological innovation and supported by such intangibles as creativity and knowledge. This paper considers first the main characteristics of networks that support the e‐economy and its source phenomenon, the emergence of technocapitalism. Networks are thought to be the main vehicle through which the e‐economy spreads, and they have major effects on the organization of business firms. The culture of technocapitalism, with its emphasis on continuous innovation and rapid adjustment, is largely behind the rising importance of networks. A second section then considers the deconstruction of business firms and its relation to networks, the e‐economy, and the rise of technocapitalism. A historical perspective is provided to show the contrast with previous eras. The deconstruction of business organizations involves a major transformation of the norms and ways in which firms are run and structured. Finally, the likely implications for transportation and shipping of the rise of the e‐economy, its networks, and the deconstruction of firms are discussed. The logistics, pricing, and infrastructure of shipping are likely to be substantially affected by the spread of the e‐economy, its networks, and the deconstruction of firms. 相似文献
3.
BRIAN SLACK 《Growth and change》1993,24(4):579-588
Abstract: Although they are required to make very large investments, port authorities are discovering that they have less and less control over their destinies. The major decisions affecting port traffic are made by shipping lines whose activities are global in scale. This paper examines the plight of public monopoly ports in a highly competitive environment. Several policy options are discussed. 相似文献
4.
Theo Notteboom 《Asia Pacific viewpoint》2007,48(3):330-343
Abstract: Container ports located in a delta of navigable waterways generally strive to develop the inland river services as a competitive transport mode, with a view to serving local and distant hinterland regions. The spatial and functional development of river‐based container networks is location‐specific and time‐specific. While each barging network and associated seaport system has its own dynamics, similarities in development patterns cannot be excluded. This paper discusses similarities and dissimilarities between the spatial and the functional development of the container river service networks of the Yangtze River and the Rhine River. It is shown that the Yangtze service network has the tendency to converge, in more than one aspect, with the (historical) development pattern of inland container services in the Rhine basin. 相似文献
5.
利用WGCNA鉴定棉花抗黄萎病相关基因共表达网络 总被引：1，自引：0，他引：1
加权基因共表达网络分析(Weighted Gene Co-expression Network Analysis,WGCNA)作为一种典型的系统生物学方法,可用来鉴定协同表达的基因模块,探索模块与目标性状之间的生物学相关性,并挖掘网络中的核心基因。黄萎病(Verticillium wilt)可严重降低棉花(Gossypium spp.)的产量及品质,因此研究抗病基因及抗病机制,对于棉花抗病育种工作具有重要意义。本研究以黄萎病菌侵染不同时间点的海岛棉(Gossypium barbadense)幼苗根尖转录组数据为基础,分析其差异表达基因,并选取在不同样本之间表达水平变异最大的前50%基因(共35,647个)进行WGCNA。结果表明,在黄萎病菌侵染条件下,共有22,850个基因差异表达,其中4685个为所有侵染时间点共有的差异基因。共鉴定到18个基因共表达模块,其中5个为抗黄萎病相关特异性模块(black、mediumpurple3、darkolivegreen、plum3模块分别与侵染2 h、6 h、48 h、72 h时间点正相关;mediumpurple2与侵染2 h时间点负相关)。GO和KEGG富集分析表明,特异性模块可以富集到有生物学意义的富集结果,如刺激响应、钙离子结合、黄酮类化合物合成代谢等抗逆相关通路。通过计算模块内基因的连通性,挖掘出了网络中的核心基因,功能预测表明,这些基因可能在逆境胁迫响应中发挥重要作用。本研究为进一步理解棉花抗黄萎病的分子机制、选育棉花抗病新品种提供了理论指导。 相似文献
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利用WGCNA鉴定玉米株高和穗位高基因共表达模块 总被引：1，自引：0，他引：1
Juan MA Yan-Yong CAO Li-Feng WANG Jing-Jing LI Hao WANG Yan-Ping FAN Hui-Yong LI 《作物学报》2020,46(3):385-394
株高和穗位高是玉米株型的重要影响因子,与产量性状紧密相关。加权基因共表达网络分析(weightedgene co-expression network analysis, WGCNA)是探索基因网络与特定性状间关联关系的重要方法,为株高和穗位高相关基因的挖掘提供新途径。本研究利用郑58、掖478、昌7-2和黄早四及其组配的杂交种郑单958、安玉5号、郑58/黄早四和掖478/黄早四,结合其在45,000株hm~(–2)和67,500株hm~(–2)条件下的转录组数据,采用WGCNA构建了2种密度条件下的共表达网络,分别得到24个和21个共表达模块,并鉴定到与株高和穗位高显著且高度相关(相关系数的绝对值0.50)的共表达模块15个,其中两性状相同的模块共6个。基因功能富集分析结果表明,株高和穗位高共表达模块主要参与生长发育、光合作用、响应光刺激、植物激素、碳水化合物合成/代谢等重要活动。根据模块内基因的连接度,发现乙烯响应因子EREB14、硫胺素酶TENA2、磷酸甘油酸激酶PGK、谷胱甘肽转移酶GST2和琥珀酸脱氢酶SUDH7等是模块内的核心基因。通过构建其局部网络,发现EREB14与已报道株高基因D8、DWF1和ZmGRF10以及C3H转录因子C3H35、C2C2-GATA转录因子GATA4和乙烯受体同源子ETR40等存在关联关系。此外,已报道株高基因An1和GA20ox3也存在于共表达模块中。以这5个已报道株高基因为核心,构建其基因网路,发现生长素转录因子ARFTF7、ARFTF26、GST39、光合系统II氧进化多肽PspB2和光合系统IN亚基PasN1等与其存在关联。15个共表达模块和核心基因的挖掘以及基因生物学功能和互作网络的解析有助于揭示玉米株高和穗位高的遗传基础。 相似文献
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Emerging CATV networks are evolution to Hybrid Fiber/Coax plants. It is widely believed that the HFC network will play an important role in providing broadband accessing service to subscribers due to it's large excess bandwidth and high penetration to the home. Asymmetry broadband data service is the main service provided in the HFC broadband access networks now. It's performance will determine whether the subscribers be satisfied or not and affect the growth of HFC broadband access networks. The authors outline the mechanism of transmitting data in the upstream channel of the HFC network, and analyze how it affecting the performance of data service. The performance of data service and TCP protocol in HFC network is examined. An optimal scheme of bandwidth allocating algorithm for the upstream channel is proposed to enhance the performance of the data service over these networks. 相似文献
9.
QING Xiao_xia 《保鲜与加工》1999,(6):105-108
This paper presents the architecture of intelligent system in the uptown, summarizes the major techniques for access networks, discusses the main technical plans of access networks for the information network aimed at the intelligent uptowns under construction and constructed in the mainland of China. 相似文献
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To overcome the limitations of the standard ellipsoidal unit neural networks, some new approaches used in ellipsoidal unit neural networks have been proposed. These new approaches address three main issues: firstly, to understand better and represent the nature of fault classification boundaries; secondly, to determine the network structure without the usual trial and error schemes; lastly, to avoid erroneous generalizations. The application in CSTR shows that the ellipsoidal unit networks can possess arbitrary nonlinear classifying ability, nonlinear interfacial describing ability, and obtain accurate and efficient diagnosis results. 相似文献
12.
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
13.
本研究选取《中国科学引文索引(CSCI)》2011—2015年的水产资源学(分类号为S931)论文及其在2016年的被引数据, 利用文献计量学方法, 从高被引论文、高被引作者、高被引机构、高被引期刊等多种角度, 基于作者和机构合作网络、关键词共现的知识图谱, 探究中国渔业资源学研究现状。研究表明, 2011—2015年研究文献数量及被引频次年际间变化不大, 呈平稳态势, 渔业资源类文献影响力较高。高被引论文及关键词共现知识图谱显示热点研究领域为增殖放流、渔情预报、渔业生物多样性、渔业生物种群生态学与摄食生态学等领域。核心作者的研究主题与当前的热门主题词切合度较高。基于作者合著形成了以程家骅、袁兴伟、刘尊雷等作者为核心的网络和以杨胜龙和樊伟为核心的网络; 基于作者共被引形成了以杨胜龙为核心的网络和以张波为核心的网络。机构合作方面较为突出的是以上海海洋大学和中国水产科学研究院黄海水产研究所为节点构成的网络。从论文期刊分布来看,学科影响力较高的期刊为《中国水产科学》、《水产学报》、《南方水产科学》和《应用生态学报》等,学科影响力排名前10位的期刊所刊发论文数量占所有发表论文数的35.8%,被引用次数占所有论文被引次数的61.5%,各期刊水产资源学文章的研究主题分布未见明显差异。 相似文献
14.
To understand the processes of growth and biomass production in plants, we ultimately need to elucidate the structure of the
underlying regulatory networks at the molecular level. The advent of high-throughput postgenomic technologies has spurred
substantial interest in reverse engineering these networks from data, and several techniques from machine learning and multivariate
statistics have recently been proposed. The present article discusses the problem of inferring gene regulatory networks from
gene expression time series, and we focus our exposition on the methodology of Bayesian networks. We describe dynamic Bayesian
networks and explain their advantages over other statistical methods. We introduce a novel information sharing scheme, which
allows us to infer gene regulatory networks from multiple sources of gene expression data more accurately. We illustrate and
test this method on a set of synthetic data, using three different measures to quantify the network reconstruction accuracy.
The main application of our method is related to the problem of circadian regulation in plants, where we aim to reconstruct
the regulatory networks of nine circadian genes in Arabidopsis thaliana from four gene expression time series obtained under different experimental conditions. 相似文献
15.
This paper looks at the divergent economic trajectories of Barcelona and Madrid since Spain's transition to democracy. It highlights how Barcelona, the city that was better positioned four decades ago to emerge as the main Spanish economic hub, has lost out to Madrid. We argue that the contrasting trajectories of the two cities have less to do with the pull of Madrid as the capital of Spain, with the development of new infrastructure in the country, or with agglomeration economies, and more with institutional factors. A growing societal divide in Barcelona along economic, social, and identity lines has led to a greater breakdown of trust and to the development of strong groups with limited capacity to bridge with one another than in Madrid. This has entailed the emergence of negative externalities that have limited the economic potential for growth in Barcelona and facilitated the rise of Madrid as the main economic hub within Spain. 相似文献
16.
JIYOUNG PARK PETER GORDON JAMES E. MOORE II HARRY W. RICHARDSON 《Growth and change》2008,39(4):548-572
In previous research, the economic impacts of temporary shutdowns of the Los Angeles–Long Beach harbors were simulated after a hypothetical terrorist attack, applying the National Interstate Economic Model to estimate state‐by‐state as well as interindustry impacts. However, the unpredictable characteristic of terrorist attacks might not be applicable to the case of a ports shutdown such as the one caused by the lockout of September–October 2002. Market participants can be expected to have contingency plans based on anticipations of a strike or shutdown. Can we identify any of these in terms of the use of alternate ports, in terms of alternate modes or even alternate time periods? The purpose of this study is to examine these questions. The approach is elaborated by testing for the possible effects of trade diversion to other West Coast ports, transportation modes, and intertemporal substitutions. We use data from WISERTrade describing commodity‐specific trade for the major West Coast ports before, during, and after the 11‐day shutdown of the fall of 2002. Shippers’ ability to divert trade is a key ingredient in the economy's ability to withstand attacks and disruptions. The work estimates the impacts on 47 industrial sectors across 50 states (and the District of Columbia). 相似文献
17.
KENG‐HSIANG CHENG YU‐CHING CHIAO HSIN‐YU SHIH TAI‐YU LEE TA‐SHUN CHO 《Growth and change》2011,42(4):517-548
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
18.
The notion of dark networks has recently received attention in the literature on policy network analysis. Dark networks are defined as illegal and covert, in contrast to bright networks which are legal and overt. In this article, we suggest a third category – grey networks – which are characterised by their use of secrecy and concealment despite their ostensibly legal status. These networks are subject to contradictory imperatives. They employ methods that cannot be openly acknowledged within the larger legal and social framework in which they function. In this article, we illustrate this concept through an interview‐based study of Australia's immigration detention network. This network enacts a deterrence policy which has been widely condemned as breaching Australia's obligations under international law. At the same time, it is required to maintain a façade of lawfulness and respect for human rights. 相似文献
19.
BP(Back Propagation) Neural networks is in the presence of the local optimization in the Neural networks training.The algorithm have slow convergence and the local convergence problem which impact the neural networks work performance.In order to cover these shortcomings and solves the size's hugeness and the low efficiency of the net problem in the traditional NN designing,the action principles of BP-Neural network's structure are analyzed,and a new method is formed which is confirmed from the Enhance genetic algorithms(EGA).The method can identify network configuration and network training methods.By adopting the number coding,self-adaptable multi-point variations operation,this method can effectively reduce the network size and the network convergence time,increase the network training speed.Tomatoes disease diagnosis examples illustrate the feasibility of this approach. 相似文献
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The traditional routing protocol for wireless mobile ad hoc networks is unable to achieve balanced energy consumption and could not adapt to the dynamic topology changes well.A novel on-demand rooting algorithm is proposed based on load balancing and mobility prediction.The proposed rooting algorithm excludes the unstable links in routing discovery,and allows the node with more energy forward the routing request packet preferentially.In addition,it adopts the active local routing recovery strategy by predicting the link connection time,and finishes the repair work before the link being actually failure.The simulation experiments demonstrate that,comparing with the traditional AODV protocol,with slight increase of the rooting control overhead,the proposed algorithm increases the average packet delivery ratio,decreases the average end-to-end delay of the data packets,and achieves load balancing in the network and prolong the life-span of the network,which shows the proposed algorithm is highly practical. 相似文献