排序方式: 共有36条查询结果,搜索用时 15 毫秒
1.
Maikel Kishna Simona Negro Floortje Alkemade Marko Hekkert 《Industry and innovation》2017,24(3):263-279
This paper focuses on the strategies of incumbents that seek to develop discontinuous innovations within the boundaries of a mature innovation system. Mature innovation systems do not provide support for these discontinuous innovations. This article focuses on exploring why incumbents in these setting engage in discontinuous innovation and what strategies they deploy to become successful. We analyse 10 cases of incumbents developing discontinuous innovations in the mature Dutch greenhouse horticulture sector. The results of our analysis show that the incumbents are primarily triggered by dissatisfaction with the current way of doing business and that the existing institutions are the main barrier to discontinuous innovation. In response, the incumbents try to circumvent the existing innovation system in their innovation process, but when successful also engage in changing the existing innovation system. This paper contributes to the understanding of the role of incumbents as source of discontinuous innovation in mature innovation systems. 相似文献
2.
对2019年北京世界园艺博览会世界园艺展示区的公共区景观设计背景、公共景观设计逻辑、主题线索的选择及重点设计内容进行了阐述。通过该项目实践,探索国际级专业园林艺术博览会公共区景观设计中,将人的行为事件作为场地设计推动力,将人的主观性与自然的存在性有效融合的方法与途径。结合项目设计重点区域,着重谈论了"种子的故事""蝶恋花"和"老树记忆"3条设计线索的演绎,阐释与表达人与自然的和谐共生关系。希望该项目能传递设计者对于自然、对于生命的尊重与情感的表达,创造出与自然山水和谐共生的现代景观。 相似文献
3.
4.
Jacomijn Pluimers Carolien Kroeze Evert Jan Bakker Hugo Challa Leen Hordijk 《Nutrient Cycling in Agroecosystems》2001,60(1-3):209-218
In this paper, present-day emissions of greenhouse gases and acidifying compounds from agriculture are analysed at the farm level. Quantitative estimates are given for these emissions from three nested systems in the Netherlands: the agricultural sector, greenhouse horticulture, and tomato cultivation under glass. Total emissions are subdivided into emissions from biogenic sources and abiogenic sources. We conclude that, although most of the emissions from the agricultural sector have biogenic sources, those from abiogenic sources should not be neglected. Abiogenic emissions are mainly from greenhouse horticulture. The cost-effectiveness of options to reduce carbon dioxide (CO2) and nitrogen oxides (NOx) emissions from on-farm combustion of natural gas in tomato cultivation under glass is analysed. An inventory is given of technical reduction options that are presently available in practice. Based on information about the costs and the reduction potential of each option, cost-efficiency curves are derived for both types of emissions. Relative to a situation where none of the described options were applied (early nineties), CO2 and NOx emissions from tomato cultivation can be reduced at most by about 70% and 75%, respectively, by combinations of technical options. This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
5.
Adolf Heißner Stefanie Schmidt Burkhardt von Elsner 《Journal of the science of food and agriculture》2005,85(4):539-548
Covering the soil with plastic film is an important method to modify soil temperature and improve the conditions for plant growth. For the optimal use of films in horticulture, it is necessary to quantify this effect, which depends particularly on the optical properties of the film. Five films, used mainly for soil covering in asparagus cultivation, were tested by measuring the soil temperature as well as the transmittance and reflectance in the short‐ and long‐wavelength bands: ‘Taschenfolie schwarz/weiß’, a film with black and white surfaces and pockets for fastening; ‘Antitaufolie’, a film with anti‐condensation coating, ‘Solartherm plus Folie’, a film with black top and transparent sides; ‘MaterBi Folie’, a biodegradable film; and ‘Thermoplus Folie’, a black polyethylene with transparent sides. All films were produced in Germany. The temperature measurements were carried out under controlled irradiation (short‐wavelength band) and ambient temperature conditions in the laboratory: first, 182 W m?2 and 11 °C at a depth of 0.4 m, and second, 340 W m?2 at 20 °C. A significant relationship between the temperature increase or decrease by covering the soil with the film and the calculated apparent quantities of the reflectance in the short and long‐wavelength band was derived (r2 = 0.85, n = 12). Furthermore, first tests with a physical model were carried out to obtain basic information, which should be used in the development of strategies for film management in the field. Copyright © 2004 Society of Chemical Industry 相似文献
6.
7.
园艺照明技术的应用和发展 总被引:10,自引:0,他引:10
本文介绍了园艺照明技术、光量的设计和园艺照明使用的新光源和灯具。 相似文献
8.
Narashans Alok Sagar Sunil Pareek Sunil Sharma Elhadi M. Yahia Maria Gloria Lobo 《Comprehensive Reviews in Food Science and Food Safety》2018,17(3):512-531
Fruits and vegetables are the most utilized commodities among all horticultural crops. They are consumed raw, minimally processed, as well as processed, due to their nutrients and health‐promoting compounds. With the growing population and changing diet habits, the production and processing of horticultural crops, especially fruits and vegetables, have increased very significantly to fulfill the increasing demands. Significant losses and waste in the fresh and processing industries are becoming a serious nutritional, economical, and environmental problem. For example, the United Nations Food and Agriculture Organization (FAO) has estimated that losses and waste in fruits and vegetables are the highest among all types of foods, and may reach up to 60%. The processing operations of fruits and vegetables produce significant wastes of by‐products, which constitute about 25% to 30% of a whole commodity group. The waste is composed mainly of seed, skin, rind, and pomace, containing good sources of potentially valuable bioactive compounds, such as carotenoids, polyphenols, dietary fibers, vitamins, enzymes, and oils, among others. These phytochemicals can be utilized in different industries including the food industry, for the development of functional or enriched foods, the health industry for medicines and pharmaceuticals, and the textile industry, among others. The use of waste for the production of various crucial bioactive components is an important step toward sustainable development. This review describes the types and nature of the waste that originates from fruits and vegetables, the bioactive components in the waste, their extraction techniques, and the potential utilization of the obtained bioactive compounds. 相似文献
9.
尽早建立具有中国特色的园艺疗法学科体系(下) 总被引:26,自引:5,他引:21
由于园艺疗法在中国尚未起步,其概念、历史、现状、功效、手法以及园职法庭园构成特点等诸方面不为大多数人所了解,因而本文回顾了英、美两国园艺疗法发展过程,概括了英、美、日三国之现状,归纳了园艺疗法在现代社会与生活中对于人们精神,社会、身体以及技能诸方面之功效,介绍了园艺疗法之手法与实施步骤,并以日本淡路景观园这校园艺疗法庭园为例,说明园艺疗法与类庭园之构成与设施在此基础上,指出了中国21世纪实施与普及 相似文献
10.
Autonomous pollination of individual kiwifruit flowers: Toward a robotic kiwifruit pollinator 总被引:2,自引:0,他引:2
Henry Williams Mahla Nejati Salome Hussein Nicky Penhall Jong Yoon Lim Mark Hedley Jones Jamie Bell Ho Seok Ahn Stuart Bradley Peter Schaare Paul Martinsen Mohammad Alomar Purak Patel Matthew Seabright Mike Duke Alistair Scarfe Bruce MacDonald 《野外机器人技术杂志》2020,37(2):246-262
There is an increasing concern that the traditional approach of natural kiwifruit pollination by bees may not be sustainable. The alternatives are currently too costly for most growers due to high labor requirements or inefficient usage of expensive pollen. This paper presents a performance evaluation of a novel kiwifruit pollinating robot designed to provide a more efficient, reliable, and cost‐effective means of producing kiwifruit. The robot comprises a novel air‐assisted sprayer, a machine vision system employing convolution neural networks, and a flower targeting system for efficient and effective application of pollen to individual flowers. We show that this pollination system is capable of individually targeting and pollinating 79.5% of flowers at 3.5 km/hr while using comparable amounts of pollen to commercial Cambrian operators. Furthermore, flowers that were successfully pollinated at 1 km/hr grew into the first robotically pollinated kiwifruit which were comparable in quality to commercially grown kiwifruit. However, the overall fruit set was found to be well below commercial requirements and further work on increasing the overall yield is required. 相似文献