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排序方式: 共有1312条查询结果,搜索用时 15 毫秒
1.
In recent years, the Asia-Pacific region has experienced several financial setbacks, including speculative attacks in 1998 and the SARS outbreak in 2003. Financial stresses of this nature are unanticipated, and not all of the dangers can be predicted by the examination of market information and macroeconomic indicators. The Early Warning System (EWS) that has been adopted by the International Monetary Fund may not be able to predict future financial crises for all possible scenarios, because shocks come in many different forms. To supplement the EWS, this paper proposes a data mining framework to measure the resilience of an economy. The resilience framework does not predict a crisis, but rather assesses the current state of health of an economy and its ability to withstand a financial shock should one occur. The framework is based on a feedback system consisting of two stages. The first stage assigns a resilience score to each economy based on a fuzzy logic scoring scheme that is built on the ambiguous reasoning of experts. The second stage uses the classification tree approach to estimate thresholds for each economic indicator, and examines the quality of the fuzzy score. The result from the second stage is then passed back to the first stage as feedback. The final result is obtained when the feedback system reaches its equilibrium state. The proposed resilience framework is applied to the external-sector and the public-sector economies of several countries to illustrate its applicability. 相似文献
2.
Sanghoon Lee Chris Podilchuk Vidhya Krishnan Alan C. Bovik 《The Journal of VLSI Signal Processing》2003,34(1-2):149-166
By exploiting new human-machine interface techniques, such as visual eyetrackers, it should be possible to develop more efficient visual multimedia services associated with low bandwidth, dynamic channel adaptation and robust visual data transmission. In this paper, we introduce foveation-based error resilience and unequal error protection techniques over highly error-prone mobile networks. Each frame is spatially divided into foveated and background layers according to perceptual importance. Perceptual importance is determined either through an eye tracker or by manually selecting a region of interest. We attempt to improve reconstructed visual quality by maintaining the high visual source throughput of the foveated layer using foveation-based error resilience and error correction using a combination of turbo codes and ARQ (automatic reQuest). In order to alleviate the degradation of visual quality, a foveation based bitstream partitioning is developed. In an effort to increase the source throughput of the foveated layer, we develop unequal delay-constrained ARQ (automatic reQuest) and rate compatible punctured turbo codes where the punctual pattern of RCPC (rate compatible punctured convolutional) codes in H.223 Annex C is used. In the simulation, the visual quality is significantly increased in the area of interest using foveation-based error resilience and unequal error protection; (as much as 3 dB FPSNR (foveal peak signal to noise ratio) improvement) at 40% packet error rate. Over real-fading statistics measured in the downtown area of Austin, Texas, the visual quality is increased up to 1.5 dB in PSNR and 1.8 dB in FPSNR at a channel SNR of 5 dB. 相似文献
3.
Hanpeng Luo Xiang Li Lirong Hu Wei Xu Qin Chu Aoxing Liu Gang Guo Lin Liu Luiz F. Brito Yachun Wang 《Journal of dairy science》2021,104(4):4441-4451
Heat stress is a major cause of welfare issues and economic losses to the worldwide dairy cattle industry. Genetic selection for heat tolerance has a great potential to positively affect the dairy industry, as the gains are permanent and cumulative over generations. Rectal temperature (RT) is hypothesized to be a good indicator trait of heat tolerance. Therefore, this study investigated the genetic architecture of RT by estimating genetic parameters, performing genome-wide association studies, and biologically validating potential candidate genes identified to be related to RT in Holstein cattle. A total of 33,013 RT records from 7,598 cows were used in this study. In addition, 1,114 cows were genotyped using the Illumina 150K Bovine BeadChip (Illumina, San Diego, CA). Rectal temperature measurements taken in the morning (AMRT) and in the afternoon (PMRT) are moderately heritable traits, with estimates of 0.09 ± 0.02 and 0.04 ± 0.01, respectively. These 2 traits are also highly genetically correlated (r = 0.90 ± 0.08). A total of 10 SNPs (located on BTA3, BTA4, BTA8, BTA13, BTA14, and BTA29) were found to be significantly associated with AMRT and PMRT. Subsequently, gene expression analyses were performed to validate the key functional genes identified (SPAG17, FAM107B, TSNARE1, RALYL, and PHRF1). This was done through in vitro exposure of peripheral blood mononuclear cells (PBMC) to different temperatures (37°C, 39°C, and 42°C). The relative mRNA expression of 2 genes, FAM107B and PHRF1, significantly changed between the control and heat stressed PBMC. In summary, RT is heritable, and enough genetic variability exists to enable genetic improvement of heat tolerance in Holstein cattle. Important genomic regions were identified and biologically validated; FAM107B and PHRF1 are the main candidate genes identified to influence heat stress response in dairy cattle. 相似文献
4.
马尾衬布变形回弹性测试方法研究 总被引:1,自引:0,他引:1
从马尾衬的高弹性特性出发 ,介绍了现有的织物变形回复性能的测试方法 ,同时分析了各个方法对于马尾衬测试的不适用性。在此基础上研究了一种简单可行的对马尾衬布变形回弹性进行测试的一种方法。 相似文献
5.
《Building Research & Information》2012,40(1):81-94
To facilitate the practice of regenerative design and development, the US Green Building Council (USGBC) and a core team envisioned a forum, a repository of information and a framework that are capable of stimulating dialogue among a diversity of practitioners and decision-makers with different disciplinary backgrounds and viewpoints. The REGEN tool is a work in progress and intended to support any regenerative design and development process, particularly in the early planning and design stages, with new questions and new types of information organized into a web of interconnection. It is intentionally neither a rating system nor a universal definition of regenerative design. Instead, it is a systems-based model of making connections at and between systemic levels, issue level and strategic level, thereby allowing the discovery of synergies, and encouraging a dialogue about place and quality of life for all life. The conceptual development of the REGEN tool is presented along with thoughts for its realization. The regenerative design process has the potential to change worldviews in a constructive way when it brings together new types of information, examples of process, and a perspective that is systems based, place based and oriented on positive outcomes. Afin de faciliter la pratique de la conception régénératrice et du développement régénérateur, le US Green Building Council (USGBC – Conseil américain du bâtiment durable) et une équipe de base ont envisagé un forum, un dépôt d'informations et un cadre qui ont la capacité de stimuler le dialogue entre une diversité de praticiens et de décisionnaires appartenant à des champs disciplinaires et ayant des points de vue différents. L'outil REGEN est un travail en cours qui est destiné à soutenir tout processus de conception régénératrice et de développement régénérateur, en particulier dans les premières phases de planification et de conception, les questions nouvelles et les nouveaux types d'informations étant organisés sous forme d'une toile d'interconnexion. Ce n'est intentionnellement ni un système de notation, ni une définition universelle de la conception régénératrice. Il s'agit plutôt d'un modèle basé sur un système, visant à établir des connexions aux niveaux systémiques, au niveau des problèmes et au niveau stratégique, et entre ces niveaux, permettant ainsi la découverte de synergies et incitant à un dialogue portant sur le lieu et la qualité de vie pour toute vie. Le développement conceptuel de l'outil REGEN est présenté, ainsi que des réflexions en vue de sa réalisation. Le processus de conception régénératrice est potentiellement capable de changer les visions du monde d'une manière constructive lorsqu'il réunit ensemble les nouveaux types d'informations, des exemples de processus et une perspective qui est basée sur les systèmes, adaptée au milieu et orientée vers des résultats positifs. Mots clés: outil de conception services écosystémiques bâtiment vivant impact net zéro qualité de vie conception régénératrice résilience conception durable 相似文献
6.
Jacob D. Petersen‐Perlman Jennifer C. Veilleux Matthew Zentner Aaron T. Wolf 《Journal of Contemporary Water Research & Education》2012,149(1):4-12
Water security is a challenge faced within many transboundary river basins. Identifying the resilient factors within a system may reduce water security concerns and enhance cooperation. In this paper, we are examining the dimensions of resilience as influenced by the rate of change and institutional capacity within river basins. Three case studies are analyzed for their water security capacity, including resilience and vulnerability, as well as institutional capacity. 相似文献
7.
Elizabeth Schuster Bonnie Colby 《Journal of Contemporary Water Research & Education》2013,151(1):70-83
Water supplies are constrained in the lower Colorado River Basin in the western United States and northern Mexico by extensive agricultural use, increasing urban populations, ecosystem needs, and the pressures of climate change. Agriculture is the largest consumptive use of water, and better understanding of how farmers are managing water supply risk and adapting to unreliable water supplies can help lead to the creation of appropriate solutions for the region. Based upon original primary data collected in 2012 in the Mexicali Valley of northern Mexico, we present findings on farm households that give us a better understanding of agricultural water management and adaptation options. We build upon these results to present voluntary, market‐based solutions to improve the region's ability to adapt to water supply variability. Increasing use of water markets and improving the cooperation among stakeholders are promising solutions with the potential to benefit agricultural and ecological water interests alike. 相似文献
8.
The dynamic properties of high-cis (98%) and cis-trans (42% cis) polybutadienes, crosslinked with 0.1 to 1.0% of crosslinking agent, have been studied using a torsion pendulum method over the temperature range ?170 to +20°C. For the high-cis rubber plots of damping factor (tan δ) against temperature showed the expected peak in the glass-transition region with an additional peak in the neighbourhood of 0°C attributable to crystallization. The cis-trans rubber showed two damping maxima in the transition region, separated by 30 to 40°C (depending on the degree of crosslinking), suggesting incipient phase separation of the component structures. The rebound resilience of the high-cis rubber at room temperature exceeded that of the cis-trans, reaching 92% at the highest crosslink density. Plots of resilience versus temperature for both rubbers showed a single minimum in the glass transition region. 相似文献
9.
We approach the issue of water productivity in agriculture by identifying five sets of drivers of change. We find that irrigation efficiencies at the field level can result in real water savings under certain conditions, but that small farmers in most of South Asia and Africa have little incentive to adopt the appropriate measures. Although water productivity improvement and water savings at the regional level are possible through a shift to economically efficient crops, such changes may be constrained by concerns with respect to domestic and regional food security, rural employment, and farming system resilience. 相似文献
10.
随着经济社会的发展,水资源系统面临的风险日益严重,探究水资源系统韧性对合理利用水资源、促进水资源可持续发展具有重要意义。根据信阳市水资源实际情况,从抵抗性、恢复性、适应性层面选取18个指标确立信阳市水资源系统韧性评价指标体系,基于熵权法确定各评价指标权重,采用模糊综合评价法、灰关联分析法、TOPSIS法,分别从评价对象的优劣等级、评价对象与最优方案之间关联度和评价对象与最优方案的接近程度等3个方面对信阳市2012—2021年的水资源系统韧性展开评价。结果表明:模糊综合评价法能更好地界定水资源系统韧性的评价标准;基于模糊综合评价法,2012—2021年信阳市水资源系统韧性水平主要为等级Ⅱ和Ⅲ,变化趋势总体是上升的,但仍存在提升的空间。 相似文献