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11.
12.
Property rights and information flows: a simulation approach 总被引:1,自引:0,他引:1
With the growth of the information economy, the proportion of knowledge-intensive goods to total goods is constantly increasing.
Lessig (The future of ideas: the fate of the commons in a connected world. Vintage, New York 2001) has argued that IPRs have now become too favourable to existing producers and that their ‘winner-take-all’ characteristics
are constraining the creators of tomorrow. In this paper we look at how variations in IPRs regimes might affect the creation
and social cost of new knowledge in economic systems. Drawing on a conceptual framework, the Information Space or I-Space to explore how the uncontrollable diffusibility of knowledge relates to its degree of structure, we deploy an agent-based
modelling approach to explore the issue of IPRs. We take the ability to control the diffusibility of knowledge as a proxy
measure for an ability to establish property rights in such knowledge. Second, we take the rate of obsolescence of knowledge
as a proxy measure for the degree of turbulence induced by different regimes of technical change. Then we simulate the quantity
and cost to society of new knowledge under different property right regimes.
相似文献
Kyeong Seok HanEmail: |
13.
The rapid urbanization in developing countries implies an increasing pressure on urban agriculture for production. As most perishable food products come from this agriculture in close proximity to population concentrations, we analysed from an agronomic point of view how market-garden farmers can meet this increasing urban demand. This work took place in the case of Mahajanga, a secondary city with high increasing demographic rate on the Northwest coast of Madagascar. Based on preliminary surveys to characterize the farming systems (on a sample of 91 farms), 11 market-garden farmers chosen in the three main agricultural zones of the urban area were surveyed during two years. Surveys aimed at understanding their decision rules in crop choices, crop allocation to land and resource management, and to estimate their room for manoeuvre to increase their leafy vegetable areas under cultivation. The wholesalers and retailers who buy the farmers’ produce were also surveyed. A previous model of decision rules regarding crop location on farm territory was used to analyse the on-farm surveys and cartographic methods (GIS and on-farm manual representations) were used to quantify the land use. We highlight the following major points. (1) The leafy vegetable production in the surveyed farms already intensively uses land: farmers have complex decision rules largely depending on the water dynamics in the two main environments (lowlands and lakesides) where leafy vegetables are cultivated during the dry season. (2) The scarcity of farmers’ resources (labour money and water) leads to very little internal room for manoeuvre to increase the leafy vegetable production in the farms. (3) At territorial level however, some land reserve exist in one of the lowlands, but not on lakesides. The water availability for agriculture must be better informed through specialized hydrologic studies, as one of the main constraints nowadays to extend the agricultural area. An extrapolation to other cases of urban agriculture is then discussed as well as the role of agronomy to help urban planners to consider the place of agriculture in the urban development. 相似文献
14.
《国际农业可持续发展杂志》2013,11(4):279-291
Many researchers have noted that not only natural ecosystems but also landscapes actively modified by humans (engineered or designed ecosystems) can significantly impact the level of ecosystem goods and availability of services, thereby impacting human and social welfare. In New Zealand, agricultural lands are the largest area of engineered ecosystems on the national landscape. Study of the welfare effects of ecosystem services delivered by agricultural land can provide important insights into the management of engineered or designed ecosystems. This paper uses the contingent valuation method (CVM) and choice modelling to estimate values of four key ecosystem services: climate regulation, water regulation, soil retention and scenic views, for New Zealand land used for arable farming. 相似文献
15.
将普通车床主轴运动机构视为由四个轴组成,每个轴视为分别装有齿轮和轴承等零件的一个子结构的装配体,利用Pro/E分别建立各子结构的三维实体模型,通过对各子结构装配实现对整个车床主轴传动的三维建模,利用Pro/E软件的Mechanism模块对整个机构进行运动学分析和运动仿真。既保证了车床主轴传动的准确性,也大大提高了设计效率。利用该方法可以使得设计人员快速、直观的对普通车床主轴运动机构进行优化设计,降低机床的研发成本,提高机床的可靠性。 相似文献
16.
In this paper we look at the manner in which ideas coming from complexity science change our understanding of the cognitive
powers of agents that is really necessary to explain the evolution of markets and of firms. The general ideas behind complex
systems dynamics and evolution are presented and then two examples are treated in detail. The first in an evolutionary model
of a market in which some new product is developed by competing firms and their “task” is to find a strategy in terms of quality
and price that will be sustainable. This essentially requires agents/firms to discover mutually compatible strategies, and
to create thereby sustainable market niches. The second example considers the internal structure of firms, in terms of their
constituent working practices and skills. It demonstrates that it is precisely their ignorance of the consequences of adopting
any particular practice that generates diversity in the emergent capabilities of firms, exploring the dimension of potential
demand and therefore leading to a successful and sustainable business sector. The work supports the notion that the cognitive
abilities that are involved are not about deduction and logic, as a traditional view of rationality might suggest, but are
about the development and contraction of interpretive frameworks, which will be different for each player. The paper links
these examples to a general recognition of the idea that complex, multi-agent systems evolve through successive “structural
attractors”—multi-dimensional dynamical systems—with temporary structural stability. Because real systems contain both the
structure and deviations from it, then there is a constant probing of structural stability and the possibility of qualitative
change to a new structural attractor. This resembles the ideas in biological evolution related to “punctuated equilibria,”
but it also links this to the idea of emergent and evolving networks of interaction, never of course near thermodynamic equilibrium.
相似文献
17.
Minyan Zhao Suocheng Dong Homer C. Wu Tengwei Su Bing Xia 《Asia Pacific Journal of Tourism Research》2018,23(8):792-805
The environmentally responsible behaviour (ERB) facilitates the sustainability of tourism destinations. This study aims to identify the key impact factors to promote visitors’ ERB in urban park and examine the impact mechanism. A total of 567 visitors were surveyed in Beijing’s Yuyuantan Urban Park. Structural equation modelling results indicate that personality traits are the most important factors that affect visitors’ ERB, while the effect of how satisfaction with interpretive services plays upon visitors’ ERB using place attachment as a mediator. Openness traits positively affect satisfaction with experiential services and general behaviour. Additionally, implications in urban park management are provided. 相似文献
18.
Vesa Kilpi Harri Lorentz Tomi Solakivi Jarmo Malmsten 《Journal of Purchasing & Supply Management》2018,24(3):247-259
Given the increasingly strategic role of external resources, acquiring knowledge about current suppliers and the broader supply market is an important and demanding task for the purchasing and supply management (PSM) function of a firm. Performance-improvement-oriented application of external supply knowledge present further challenges for the function. To examine this, we draw on the knowledge-based view and develop a hypothesized model in which supply knowledge acquisition drives PSM exploration and exploitation orientations which in turn mediate the organizational status of PSM function in terms of supply performance. We test the model on an SME-focused and survey-based dataset, using structural equation modelling. Our results indicate that an exploitative orientation is associated with knowledge gained from the supply base, whereas an explorative orientation is predominantly associated with supply market knowledge and less with supply base knowledge, suggesting natural pairings. The findings also show how an exploitative development orientation mediates the positive association of the PSM function's organizational status with supply performance. Driven by supply base knowledge, a status-empowered exploitative PSM orientation may suppress supply market based explorative orientation in resource-scarce SMEs, thus appearing to serve as the sole path to supply performance. Our research contributes by pointing out the significance of the knowledge-resource, and the knowledge-based view, in understanding performance in PSM. 相似文献
19.
Jonas De Vos Tim Schwanen Veronique Van Acker Frank Witlox 《International Journal of Sustainable Transportation》2019,13(3):180-196
Previous studies have indicated that travel satisfaction - the experienced emotions during, and cognitive evaluation of, a trip - can be affected by travel mode choice and other trip characteristics. However, as satisfactory trips might improve a person's attitude towards the used mode, persons may be more likely to use that same mode for future trips of the same kind. Hence, a cyclical process between travel mode choice and travel satisfaction might occur. In this paper we begin to analyse this process—using a structural equation modelling approach on cross-sectional data—for people who engage in walking and cycling for leisure trips in the Belgian city of Ghent. The focus on walking and cycling reflects recent studies indicating that active travel is often associated with the highest levels of travel satisfaction. Results of this exploratory analysis offer tentative support for the idea of a cyclical process: the evaluation of walking and cycling trips positively affects the respondents' attitude towards the respective mode, which in turn has a positive effect on choosing that mode. 相似文献
20.
This study aims to theoretically integrate quality factors of both medical and hospitality services in medical tourism. Medical tourism comprises both medicine and tourism. Although the core product in medical tourism is medical treatment, attractive hospitality and travel options are also essential. Despite the dual nature of medical tourism, the two aspects of this concept have not been integrated in a unique framework. This study attempts to fill this gap using interpretive structural modeling (ISM). According to ISM, although factors of medical services and hospitality services are independent from each other, these factors have vital impacts on perceived value, satisfaction, and loyalty. 相似文献