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111.
Béla Nagy J. Doyne Farmer Jessika E. Trancik John Paul GonzalesAuthor vitae 《Technological Forecasting and Social Change》2011,78(8):1356-1364
Moore's Law has created a popular perception of exponential progress in information technology. But is the progress of IT really exponential? In this paper we examine long time series of data documenting progress in information technology gathered by [1]. We analyze six different historical trends of progress for several technologies grouped into the following three functional tasks: information storage, information transportation (bandwidth), and information transformation (speed of computation). Five of the six datasets extend back to the nineteenth century. We perform statistical analyses and show that in all six cases one can reject the exponential hypothesis at statistically significant levels. In contrast, one cannot reject the hypothesis of superexponential growth with decreasing doubling times. This raises questions about whether past trends in the improvement of information technology are sustainable. 相似文献
112.
Michael C. Withers Paul Louis Drnevich Louis Marino 《Journal of Small Business Management》2011,49(4):515-536
Innovation requires the entrepreneurial capabilities of opportunity recognition and opportunity exploitation. Such capabilities generally accrue over time from a firm's cumulative learning and experience. In this study, we theorize that firm age should therefore moderate the firm's ability to leverage these capabilities for innovation activity, such that older firms can obtain higher outputs from their capabilities than younger firms can. We examine this relationship using a sample of 676 small and medium enterprises. We find that when both younger and older firms have highly developed innovation capabilities, older firms appear to enjoy higher levels of innovation activity than younger firms do. However, younger firms generally appear more likely to have higher levels of innovation activity than older firms do, when neither firm has highly developed innovation capabilities. We conclude with a discussion of the implications of these findings for research and practice. 相似文献
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114.
When land parcel boundaries are surveyed for purposes of registration in most southern African countries, the cadastral survey records and diagrams prepared have to be examined and approved by the Surveyor General first before they can be registered in the Deeds Registries. For such records to be approved, their quality must conform to requirements stipulated in relevant acts and regulations. Where regulatory requirements are not met, the records are rejected and returned for corrections and resubmission. From a cross-organizational context, poor quality documents lodged upstream have the effect of congesting examination processes downstream as records are rejected and returned backwards due to quality failure. The paper proposes a quality performance measurement model to analyze quality performance in land administration work processes. The developed model is tested on 2 survey examination and approval sites and 3 deeds registration sites in Namibia, Zimbabwe and South Africa. Based on below expected quality results obtained at one of the sites, a root cause analysis was conducted to establish recurring and underlying causal factors upon which quality improvement strategies can be built on. 相似文献
115.
The present liability system for managing environmental risks has had huge transaction costs through the courts with limited funds actually utilized for compensation (except to the lawyers) and cleanup of wastes. This paper discusses the use of insurance coupled with well-specified standards as an alternative to the current system. It illustrates the potential for the use of these policy tools in the context of two environmental risk management problems: providing liability protection to contractors involved in asbestos removal and protecting commercial property lenders and owners from liabilities associated with environmental contamination. 相似文献
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Journal of the Academy of Marketing Science - 相似文献
119.
Paul G. Chapman 《Metroeconomica》1990,41(3):249-258
A two period model of the training decision is analysed using a human capital approach. The segmented labour market model where training opportunities distinguish entrants is compared with a competitive structure with homogeneous entrants. The main conclusions in the paper are the clear effects of training wages and the different effects in the two market structures of both wages and employment prospects in the unskilled market on training. 相似文献
120.
Alternative land management practices, including agroforestry, help to maintain levels of soil organic matter (SOM) and can facilitate soil carbon (C) sequestration for mitigating atmospheric CO2 emissions. This study quantified C inputs and determined the changes of the soil C pool in a 19-year-old Gliricidia sepium alley cropping system, studied at two fertiliser levels (tree prunings only [? N], and tree prunings plus chicken manure [+ N]), and was compared to a sole crop system. Carbon input from tree prunings ranged from 455 to 457 g C m? 2 y? 1, whereas C inputs from crop residues were similar between alley- and sole crops ranging from 121 to 159 g C m? 2y? 1. The soil organic C (SOC) pool in the alley crop was 16–23% higher than the sole crop. In the 19th year of alley farming, SOC was significantly higher (p < 0.05) in the alley crop (3.2%) compared to the sole crop (2.4%), and was also greater compared to that at the time of establishment of the agroforestry system (2.8%). Gross SOC turnover to a 20-cm depth ranged from 12 to 14 years in the + N and ?N alley crops compared to 49 and 50 years in the + N and ?N treatments for the sole crops. Residue stabilisation efficiency in the alley crops was 39% and 55% in + N and ?N treatments respectively. 相似文献