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161.
马筱聪 《价值工程》2015,(2):191-192
本文分析了目前高校教学量化管理工作中普遍存在的问题和矛盾,提出了一种基于B/S模式的高校教师教学工作量化管理网络化系统的解决方案,论述了系统开发的必要性和实际意义;文章介绍了系统的结构及主要功能模块,以及系统在实践中的应用效果。  相似文献   
162.
Genetically modified (GM) crops are popular in many regions of the world, but their deployment in Africa is hindered by safety concerns and regulatory issues, although the continent is in dire need of boosting its food production. Although consumers' acceptance of GM food has been analyzed in many continents, no such studies have been conducted in Africa. Therefore, a survey of 604 consumers was conducted in Nairobi, Kenya, in 2003, to gauge consumers' awareness of GM crops, their willingness to pay (WTP) for GM food, and the factors that influence their WTP. Consumers' knowledge of GM crops was limited and only 38% of the 604 respondents were aware of GM crops. People in higher education and income groups were more aware than others. Regardless, people were generally appreciative of the technology, and a large majority (68%) would be willing to buy GM maize meal at the same price as their favorite brand. Consumers were, however, concerned about possible side effects, especially on the environment and biodiversity. WTP was estimated using a double‐bounded dichotomous choice model, and the mean WTP was found to be 13.8% higher than the average price of non‐GM maize meal. Perceptions of health risk, and ethical and equity concerns had a negative influence on the likelihood of purchasing GM maize meal, whereas trust in government to ensure food quality had a positive influence on WTP. People with at least some secondary education and those in the high‐income category were more likely to purchase GM maize meal at the same price. The study concludes that, because awareness is still low, appropriate communications are needed to involve the consumer in the debate. Consumers' acceptance in this study was high, but the research needs to be expanded to rural areas, where most consumers live, and other survey methods need to be explored.  相似文献   
163.
In an effort to improve productivity and profits, many farmers have replaced traditional livestock breeds with higher yielding alternatives. While such changes may bring about short‐term economic gains, the loss of traditional livestock breeds could result in the loss of an important genetic resource as a variety of important genetic traits adapted to local conditions gradually become less common in the population. This is a particular problem in Africa, where livestock make a substantial contribution to human livelihoods. Using the example of cattle in Kenya's pastoral livestock markets this study uses a choice experiment approach to investigate buyers' preferences for indigenous breeds such as the Maasai Zebu. The analysis employs a latent class approach to characterize heterogeneity in valuations both within and across respondents buying cattle for breeding, slaughter, or resale. The results show that there are at least three classes of buyers with distinct preferences for cattle traits and that most buyers favor exotic rather than indigenous breeds. Such preferences have implications for the conservation of indigenous cattle in Kenya and in other developing countries and suggest that some form of intervention may be required to ensure the preservation of this important animal genetic resource.  相似文献   
164.
Recent increases in food and other commodity prices have highlighted concerns that many poor countries are net food importers and higher food prices would worsen their trade balances. In this article, we analyze the changes in food trade balances associated with the 32% increase in food prices from 2000/2001 to 2004/2005. We find a small deterioration in food trade balances of low‐income countries and an improvement in middle‐income countries. The deterioration is most severe for countries in conflict and small island states, so attention should be placed first on these countries and on a few very‐low‐income countries that are also vulnerable. Because low‐income countries as a group had much lower agricultural GDP growth rates than middle‐income countries, the answers to food vulnerability in low‐income countries should probably be addressed within the context of incentives for agricultural production.  相似文献   
165.
This study assesses the potential impact of rising world food prices on the welfare of Ugandan households. While Uganda experienced sharply higher food prices in 2008, as a landlocked, food‐exporting country the causes of those price changes were mainly regional and indirect rather than directly transmitted from global markets. Using trade volumes, food prices, and household survey data we describe how Uganda, unlike some other countries, is partially shielded from direct impacts of global food price movements. Although the majority of Ugandans are net food buyers, the adverse impact at household‐level of rising global prices is moderated by the relatively large quantity and range of staples consumed that come from home production. Moreover, several of these are not widely traded. Some population groups in Uganda are vulnerable to rising food prices, however, primarily those for whom maize is an important staple, including those dependent upon humanitarian relief and the urban poor. Only a relatively small group of Ugandan households will benefit directly and immediately from rising food prices—the significant net sellers of food crops constituting between 12% and 27% of the population. In this assessment we do not estimate the level and extent of wider second round effects from these higher prices.  相似文献   
166.
Extreme interannual variability of precipitation within Ethiopia is not uncommon, inducing droughts or floods and often creating serious repercussions on agricultural and nonagricultural commodities. A dynamic climate module is integrated into an economy‐wide model containing a detailed zonal level agricultural structure. This coupled climate‐economic model is used to evaluate the effects of climate variability on prospective irrigation and infrastructure investment strategies, and the ensuing country‐wide economy. The linkages between the dynamic climate module and the economic model are created by the introduction of a climate‐yield factor (CYF), defined at the crop level and varied across Ethiopian zones. Nine sets of variable climate (VC) data are processed by the coupled model, generating stochastic wet and dry shocks, producing an ensemble of potential economic prediction indicators. Analysis of gross domestic product and poverty rate reveal a significant overestimation of the country's future welfare under all investment strategies when climate variability is ignored. The coupled model ensemble is further utilized for risk assessment to guide Ethiopian policy and planning.  相似文献   
167.
168.
The persistence of agricultural protectionism throughout the world is intriguing given the widely recognized benefits of free trade. The political economy literature over the last decades has considered groups’ interest, politicians’ preferences, and their interactions within domestic politics as the primary forces driving agricultural protection. Yet, a growing body of studies suggests that it would be judicious to weigh in consumers’ or taxpayers’ perspectives in deciphering the nature of agricultural protection. This study examines U.S. citizens’ preferences about government intervention in agriculture and trade. Results show that they are in strong support of agricultural protection and their perceptions of national food security, family farms, environmental sustainability, and multifunctionality of agriculture play a significant role in shaping their support/opposition toward government intervention. The conventional political economy literature theorizes that consumers or taxpayers would oppose public policies that increase their tax burden; however, in the case of the farm sector, they have little incentive to voice their objections given the costs of farm programs are spread across a large number of consumers and taxpayers. U.S. citizens’ support for government involvement in agriculture as reported in this and other prior studies does not lend support for such political economy explanation.  相似文献   
169.
Interest in supporting local and regional food systems is rising and food hubs have attracted considerable attention among Federal, State, and local policymakers. This study explores the problem of endogenous hub location in fresh produce value chains in the Northeastern United States. To overcome limitations in the literature, we incorporate the effects of economies of scale and production seasonality into our models. Three experimental models are designed to examine the effects of alternatively applying yearly, quarterly, and monthly data on model solutions. We explicitly assess how interactions of scale economies and seasonality influence the structure and spatial attributes of an optimal regional produce aggregation hub system. The three models generate marketed different solutions and in many respects they lead to different conclusions about developing local/regional supply chains. The monthly model allows for production seasonality and actual hub operation cycle frequency and thus leads to more efficient hub solution with rich policy implications.  相似文献   
170.
In December 2014, the U.S. and Mexico agreed to a suspension agreement that set a $22.25/cwt import price floor on U.S. sugar imports from Mexico. A partial equilibrium trade model was developed to estimate the economic impact the agreement would have had if it had been in effect from 2008 to 2014. In years when the price floor would have been binding, on average, U.S. producers would have gained $138 million and Mexican producers would have lost $218 million. However, total Mexican welfare would have actually increased by $11.5 million. Furthermore, the average price floor that would have maximized total Mexican welfare over that period is $22.76/cwt. Also, under certain supply and demand elasticity conditions, the average price floor that would have maximized joint U.S. and Mexican producer welfare over that period is $21.91/cwt. The latter two estimates are both close to the actual price floor agreed to in the 2014 Suspension Agreement.  相似文献   
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