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21.
Medic (Medicago spp.) pastures are widely grown in rotation with dryland cereal crops in Mediterranean climate zones of Australia. Attempts since the 1960's to introduce this system to Mediterranean west Asia and north Africa (the native region of medic) have not lead to significant adoption; farmers in the region recognize medic, but as a weed and natural pasture plant. This first detailed economic evaluation of the rotational medic system was conducted using a whole-farm linear programming model based on the agricultural system of north-west Syria. The model represents in detail impacts of rotation on yields, labor requirements of alternative farm activities, availability of family and hired labor, subsistence income requirements, livestock feed sources and uses at different times and a choice of sheep stocking rates. Biological data for the analysis are based on a large six-year cropping and grazing experiment near Aleppo on terra-rossa soil with rainfall mainly in winter and averaging about 330 mm annually. The trial compared a dryland medic-wheat system and traditional two-year rotations of wheat with: fallow, watermelon, lentil and vetch. Results indicate that, given current prices and yields from the trial, medic is less profitable than traditional rotations. The model was used to investigate situations in which medic would be economically preferred. Selection of a medic rotation by the model was found to be particularly sensitive to the area of the farm and the price of labor. On small farms, labor availability per hectare is high, favouring the production of labor intensive crops such as lentil and watermelon. On larger farms, labor costs of these enterprises are substantial, increasing the relative profitability of medic, especially if labor prices increase. Interestingly, the relative desirability of medic is more sensitive to its impact on subsequent wheat crops than to the level of pasture production. We also found that modest increases in the prices of sheep products (especially milk) have a major impact on the economic performance of medic. These insights will allow improved focusing and targeting of future research and extension activities.  相似文献   
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Abstract This paper provides evidence on the impact of company training, of post-compulsory education and of the UK Youth Training Scheme in the late 1980's on the earnings of 21-year-old employees in England and Wales. Earnings equations are estimated for each of seven groups of employees who have followed alternative routes from compulsory education into employment, allowing for selectivity into these routes. There are several findings, including: both high parental social class and better school qualifications help to channel people into higher status routes, while high local unemployment has the opposite effect; participation in company training in long spells substantially raises wages but short spells do not; YTS participation fails to raise, and possibly substantially lowers, wages even three years after graduation compared to those who left school at 16 and went to work and received no training; there is weak evidence that, even for those that do not enter higher education, it is better to stay on at school after 16 than go into YTS.  相似文献   
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Commercial project management systems focus on preproject planning and after-the-fact documentation, but not on the dynamic problem solving required in day-to-day project management. Yet the need for risk-oriented management is clear. To understand and control project risks, managers must be able to identify problems as they occur, immediately assess their downstream impacts, and plan a course of action. The Advanced Risk Management System (ARMS) is a prototype system built to address the issues of identifying, analyzing, prioritizing, monitoring, and controlling project risk. ARMS uses expert systems, data base management, and hypermedia technologies to capture and classify project schedule problems, to determine their semantic impacts to future activities, and to alert appropriate project personnel in advance of problem occurrence.  相似文献   
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北极冰川融化将使跨北极通航成为可能,运输公司可减少40%的航运距离。马六甲海峡也将不再垄断国际通运。国际经济将进一步融合。  相似文献   
27.
A Product and Process Model of the Technology-Sourcing Decision   总被引:1,自引:0,他引:1  
The technology‐sourcing decision traditionally has examined the choice either to innovate internally or to acquire technology from outside sources. The increasing complexity of this decision requires a move beyond the simple “make‐versus‐buy” dichotomy. We seek to test factors that influence the technology decision of subsidiaries for product and process technology across the continuum of options from internal development to outsourcing. We also explore concordance between the research streams of new product development and technology sourcing. Regression models are used to analyze data from 187 subsidiaries that suggest product and process technology development decisions sometimes are associated with similar factors and at other times they diverge. In particular, we find that external product and process technology acquisition decisions are associated negatively with differentiation goals and associated positively with product dynamism. While external product acquisition is associated negatively with a low cost goal and positively with increasing distance between primary marketing and R&D operations, external process technology acquisition is associated positively with high competitive intensity. Implications include the following: (1) While external product technology acquisition may provide quicker or even less expensive initial solutions, external reliance makes it difficult to maintain a long‐term positional advantage; (2) When greater distances separate key functional activities, external partners may provide solutions that are more responsive to local consumer needs, and the potential for improved communication may allow for quicker adaptation and increased flexibility; (3) In highly dynamic product situations, internal development, while providing greater control, can be expensive and can result in technologies that are not accepted by the marketplace; and (4) As competitive intensity increases, strategic imperatives may reduce the focus on product design and development and may require increasing concentration on manufacturing costs and efficiencies.  相似文献   
28.
We evaluate the appropriateness of regulation within the Canadian cable television industry by applying both parametric and non-parametric approachesto measure scale efficiency. Although we begin with a sample offering adequatedegrees of freedom for parametric estimation, important policy issues lead us toconsider further estimation over sub-samples. Since some of these sub-samplesare small enough that parametric models cannot guarantee reliable estimates, weobtain production characteristics non-parametrically through data envelopmentanalysis. The nonparametric results for scale efficiency support the parametricresults. We find evidence against a natural monopoly argument that might havejustified continuation of the mandated monopolization of Canadian cable televisionservice. By the end of the sample period, there were no longer substantial economiesof scale in most relevant markets.  相似文献   
29.
Increasingly popular tailored regulation (TR) initiatives like the Environmental Protection Agency's Project XL allow industrial facilities to voluntarily substitute site-specific environmental performance standards for inefficient command-and-control regulations. TR can significantly reduce participants' costs of complying with environmental regulations, but in doing so it can also give these participants a competitive advantage. Here we develop an analytical model to show that TR can have adverse welfare effects when if enables relatively inefficient firms in oligopolistic markets to “steal” market share from more efficient firms, and we characterize the regulatory policies that give rise to such outcomes. We also show that regulators' efforts to diffuse the benefits of site-specific agreements among nonparticipating firms dampen incentives to participate in TR.  相似文献   
30.
Statement of Financial Accounting Standard (SFAS) No. 106 on Nonpension Postretirement Benefits (NPB) provides managers with a relatively long adoption window and choice of transition methods which can be used by affected companies to manage earnings. This paper examines whether management's choice of adoption timing is motivated by the desire to manage earnings. Fisher's [1934] exact probability analysis is used to test the hypothesis regarding profitability of a sample of 200 early and late adopters of SFAS No. 106. The results indicate that the profitability of adopting the income-reducing accounting standard (SFAS No. 106) early is significantly higher for more profitable firms than for less profitable firms.  相似文献   
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