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91.
Krista Merry Pete Bettinger Jacek Siry J. M. Bowker Steven Weaver Zennure Ucar 《Landscape Research》2018,43(5):721-734
The recreational opportunities available across landscapes of the Southern United States can be broad and diverse, and collectively are considered a subset of cultural ecosystem services. In describing the settings of recreational opportunities, a number of methods have been proposed that are based in part on geographic information and that can be facilitated by geographical analyses. Presented here are two expedient and cost-effective methods for assessing the recreation supply potential of large, heavily-roaded areas that are situated mainly with privately-owned land in the Southern United States. One land classification process uses fine-scale aerial imagery and other geospatial data in a process that results in three recreational opportunity setting zones with a focus on motorised sightseeing: foreground, background, and remote areas. Within these zones, land cover was derived and aggregated into three major land cover classes, including forest, agriculture, and bare ground classes. Further, a second process uses fuzzy classification methods, and through this highly suitable recreation settings were identified. Each recreational opportunity zone is further subdivided by public- and privately-owned land. We feel these types of recreation setting models can allow managers and planners to gain an understanding of the passive recreation potential of heavily-roaded privately-owned landscapes typical of the Southern United States. 相似文献
92.
Pete Halley Rulande Rutgers Steve Coombs Janine Kettels John Gralton Gregor Christie Malcolm Jenkins Henry Beh Kim Griffin Ranjith Jayasekara Greg Lonergan 《Starch - St?rke》2001,53(8):362-367
This paper examines the development of starch‐based plastics for use as biodegradable mulch film. A variety of starch‐based polymers are blended with high performance biodegradable polyester polymers in order to determine the applicability of films to be processed on a film blowing line and to perform well in mulch film field trials. The process of material formulation, film blowing processing and scale‐up and performance properties are highlighted for a successful material. Insights into future developments of starch‐derived biodegradable polymers are given. 相似文献
93.
Pete Goldsack Richard Maguire 《今日电子》2006,(8):48-49
随着网络运行商的数据服务和更高速服务的扩大,移动设备的功能有了新的需求。移动设备的设计者已经开始在他们的产品中逐渐集成CDMA2000和1xEV—DO或EDGE、W—CDMA和HSDPA等技术。这些技术非常复杂,并且为终端用户提供的服务更加灵活多样,因此就要求移动设备的设计者在将产品交付生产之前,对产品的应用性能进行完备的测试。 相似文献
94.
95.
PurposePatient-reported subjective responses have become increasingly popular in describing contact lens visual performance and discriminating between designs. The purpose of the current study is to evaluate the ability of patient-reported measures of vision to quantify the perceptual effects of defocus.MethodsTen young (18–35 years) subjects rated their subjective visual performance monocularly on 3 scales following wear of their optimal monocular distance correction and nine different blurring lenses (?0.50 to +1.50 in 0.25 D steps) in a trial frame. The three scales used were a 0–100 numeric rating scale (NRS), a 100 mm visual analog scale (VAS), and a 5 point (“Poor”, “Fair”, “Average”, “Good”, “Excellent”) categorical rating scale (CRS).ResultsMixed linear modeling results found no significant effects either for eye or trial number, but did find a significant effect due to blurring lens power (p < 0.0001), with ratings decreasing with increasing levels of blur for all scales. Results were not significantly different between the NRS and VAS at any level of blur, with limits of agreement falling within 22% of the measurement scale. CRS ratings were about 15 units lower than the other scales on average, with limits of agreement that varied with lens power and were roughly 3 times as large. Across scale internal consistency was 0.94.ConclusionsThe NRS and VAS yield virtually identical rating responses, but both differing slightly, however from the CRS. Each scale successfully discriminated levels of blur smaller than 0.25 D with only a single measurement. 相似文献
96.
Carl Lagoze Herbert Van de Sompel Michael Nelson Simeon Warner Robert Sanderson Pete Johnston 《Concurrency and Computation》2012,24(18):2221-2240
Digital scholarship offers the opportunity to move beyond the limitations of traditional scholarly publication. Rather than limiting scholarly communication to text‐based static documents, the Web makes it possible for scholars to expose and share the full evidence of their research including data, images, video, and other genre of materials. These aggregations of evidence, or compound documents, can then be integrated into a linked data cloud, the basis of Scholarship 2.0—an open environment in which scholars collaborate and build new knowledge on the existing scholarship. We present Open Archives Initiative–Object Reuse and Exchange (OAI–ORE), a set of standards to identify and describe aggregations of WebResources, thereby making the Scholarship 2.0 vision possible. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
97.
We review and qualitatively assess the importance of interactions and feedbacks in assessing climate change impacts on water and agriculture in Europe. We focus particularly on the impact of future hydrological changes on agricultural greenhouse gas (GHG) mitigation and adaptation options. Future projected trends in European agriculture include northward movement of crop suitability zones and increasing crop productivity in Northern Europe, but declining productivity and suitability in Southern Europe. This may be accompanied by a widening of water resource differences between the North and South, and an increase in extreme rainfall events and droughts. Changes in future hydrology and water management practices will influence agricultural adaptation measures and alter the effectiveness of agricultural mitigation strategies. These interactions are often highly complex and influenced by a number of factors which are themselves influenced by climate. Mainly positive impacts may be anticipated for Northern Europe, where agricultural adaptation may be shaped by reduced vulnerability of production, increased water supply and reduced water demand. However, increasing flood hazards may present challenges for agriculture, and summer irrigation shortages may result from earlier spring runoff peaks in some regions. Conversely, the need for effective adaptation will be greatest in Southern Europe as a result of increased production vulnerability, reduced water supply and increased demands for irrigation. Increasing flood and drought risks will further contribute to the need for robust management practices.The impacts of future hydrological changes on agricultural mitigation in Europe will depend on the balance between changes in productivity and rates of decomposition and GHG emission, both of which depend on climatic, land and management factors. Small increases in European soil organic carbon (SOC) stocks per unit land area are anticipated considering changes in climate, management and land use, although an overall reduction in the total stock may result from a smaller agricultural land area. Adaptation in the water sector could potentially provide additional benefits to agricultural production such as reduced flood risk and increased drought resilience.The two main sources of uncertainty in climate impacts on European agriculture and water management are projections of future climate and their resulting impacts on water and agriculture. Since changes in climate, agricultural ecosystems and hydrometeorology depend on complex interactions between the atmosphere, biosphere and hydrological cycle there is a need for more integrated approaches to climate impacts assessments. Methods for assessing options which “moderate” the impact of agriculture in the wider sense will also need to consider cross-sectoral impacts and socio-economic aspects. 相似文献
98.
Ashley E. Pete Daniel Kress Marina A. Dimitrov David Lentink 《Journal of the Royal Society Interface》2015,12(110)
Birds improve vision by stabilizing head position relative to their surroundings, while their body is forced up and down during flapping flight. Stabilization is facilitated by compensatory motion of the sophisticated avian head–neck system. While relative head motion has been studied in stationary and walking birds, little is known about how birds accomplish head stabilization during flapping flight. To unravel this, we approximate the avian neck with a linear mass–spring–damper system for vertical displacements, analogous to proven head stabilization models for walking humans. We corroborate the model''s dimensionless natural frequency and damping ratios from high-speed video recordings of whooper swans (Cygnus cygnus) flying over a lake. The data show that flap-induced body oscillations can be passively attenuated through the neck. We find that the passive model robustly attenuates large body oscillations, even in response to head mass and gust perturbations. Our proof of principle shows that bird-inspired drones with flapping wings could record better images with a swan-inspired passive camera suspension. 相似文献
99.
Melina Peteán Alejandro Beccaría Patricia Burns Guillermo Sihufe María Florencia Zacarías Ana Binetti Jorge Reinheimer Gabriel Vinderola 《International Journal of Dairy Technology》2014,67(1):39-46
Buttermilk is a suitable substrate for fermentation with proteolytic strains of Lactobacillus in order to release peptide fractions able to enhance the gut mucosal immune system. We aimed to determine the influence of the degree of proteolysis of buttermilk proteins on their functionality. Animals received for seven consecutive days the cell‐free fraction of 10 or 20% (w/v) buttermilk fermented with Lactobacillus delbrueckii subsp. lactis 210 at pH 6. The pH was controlled either with NaOH or Ca(OH)2. No significant differences in the number of IgA‐producing cells in the small intestine of mice were found. The functional capacity of the product under study was not affected by the technological variables considered. 相似文献
100.
Pete Lockhart 《软件》2009,(3):50-51
工厂级别的网络系统需要与集中过程控制和制造执行系统互联互通,TIA-1005就是为了实现在工业安装中全新结构化布线的理念。 相似文献