Data mining of resilience indicators

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.     

Foveation-Based Error Resilience and Unequal Error Protection over Mobile Networks

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.     

Genomic analyses and biological validation of candidate genes for rectal temperature as an indicator of heat stress in Holstein cattle

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.     

马尾衬布变形回弹性测试方法研究

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。     

Dynamic-mechanical properties of polybutadiene rubbers

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.     

白炭黑175GR在载重轮胎胎面胶中的应用

研究白炭黑175GR在载重轮胎胎面胶中的应用.回归分析试验结果表明, 白炭黑175GR与炭黑采用适当的比例并用,可使胎面胶压缩生热明显降低,抗撕裂性能和弹性显著提高,拉伸强度和拉断伸长率有所提高,抗屈挠龟裂性能有所改善.     

波齿复合垫片骨架结构及压缩回弹性能的研究

通过有限元分析和模拟,在不同的骨架结构参数下,对波齿复合垫片的压缩回弹性能进行测试。从而得到不同状态下的应力分布、压缩回弹性能和结构参数的关系,进而用于优化波齿复合垫片的结构性能。分析结果表明:在相同波深的条件下,随着波齿距的增大,压缩率相应增大,而回弹率却相应减小。     

基于改进模糊物元模型的区域农业水资源系统恢复力评价

区域农业水资源是农业可持续发展的基础 ,各种生态环境问题的发生致使农业水资源系统退化特征日益明显 ,识别区域农业水资源系统恢复力对于维持农业大系统稳定发展具有重要意义.以黑龙江省农垦红兴隆管理局为研究对象 ,在建立农业水资源系统恢复力评价指标初选集的基础上 ,选取主成分-相关分析法筛选评价指标 ,构建评价指标体系 ,采用指标相关性的指标权重法计算指标权重 ,运用改进模糊物元模型评价农业水资源系统恢复力.文中研究成果为维持农业水资源系统良性运行、保障区域水安全与粮食安全提供了科学依据.