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51.
In modeling disease transmission, contacts are assumed to have different infection rates. A proper simulation must model the heterogeneity in the transmission rates. In this article, we present a computationally efficient algorithm that can be applied to a population with heterogeneous transmission rates. We conducted a simulation study to show that the algorithm is more efficient than other algorithms for sampling the disease transmission in a subset of the heterogeneous population. We use a valid stochastic model of pandemic influenza to illustrate the algorithm and to estimate the overall infection attack rates of influenza A (H1N1) in a Canadian city.  相似文献   
52.
This study develops a robust automatic algorithm for clustering probability density functions based on the previous research. Unlike other existing methods that often pre-determine the number of clusters, this method can self-organize data groups based on the original data structure. The proposed clustering method is also robust in regards to noise. Three examples of synthetic data and a real-world COREL dataset are utilized to illustrate the accurateness and effectiveness of the proposed approach.  相似文献   
53.
54.
Abstract

With a shift to more automation technology, social acceptance of technology plays an important role in the manufacturing sector. To what extent this occurs, and affects the adoption of technology, has been less researched, but is important in deciding how such technology is introduced, and the nature of the shift from labour-intensive manufacturing to automation. This research applies the revised technology acceptance model (TAM) to examine the impact of social and individual antecedents on the acceptance of automation manufacturing technology. Survey data are collected from 258 Chinese manufacturers. Results suggest that perceived norms significantly affect organizational intention to use automation manufacturing technology both directly and via perceived usefulness; organizational efficacy explains the intention to use via mediating effect of perceived usefulness and perceived ease of use. This research is one of the first extending and applying TAM from individuals to organizations.  相似文献   
55.
本文介绍了岩石可钻性能全法在油田现场实脸研究的成果:确定其可钻性指标凡对地层的适用范围,证明K指标比其他可钻性指标能更容易、史好地反映出井下实际地层可钻性变化情无,用K指标预浏钻速与实际钻速接近.  相似文献   
56.
“Cruising” infants can only walk using external support to augment their balance. We examined cruisers' understanding of support for upright locomotion under four conditions: cruising over a wooden handrail at chest height, a large gap in the handrail, a wobbly unstable handrail, and an ill‐positioned low handrail. Infants distinguished among the support properties of the handrails with differential attempts to cruise and handrail‐specific forms of haptic exploration and gait modifications. They consistently attempted the wood handrail, rarely attempted the gap, and occasionally attempted the low and wobbly handrails. On the wood and gap handrails, attempt rates matched the probability of cruising successfully, but on the low and wobbly handrails, attempt rates under‐ and overestimated the probability of success, respectively. Haptic exploration was most frequent and varied on the wobbly handrail, and gait modifications—including previously undocumented “knee cruising”—were most frequent and effective on the low handrail. Results are discussed in terms of developmental changes in the meaning of support.  相似文献   
57.
In recent years, attention on the issue of poverty in Singapore has been increasingly placed in the spotlight. This study examines the various types of attitudes among Singaporeans and how they are formed, relating them to the broader institutional context of Singapore. A mixed method design is employed where clusters or groups of attitudes are derived through the use of cluster analysis. Subsequently, discourses of poverty and welfare attitudes are construed through qualitative interviews with the aid of Foucauldian Discourse Analysis. Quantitative findings point to three clusters of attitudes: ‘Conservatives’, ‘Liberals’, and ‘Sui Generis’. Qualitative findings, however, show that ‘Sui Generis’ ultimately align themselves closer to either ‘Conservatives’ or ‘Liberals’ in their discourses of welfare. In fact, respondents in all three clusters reproduce state discourses, albeit in varying ways. In essence, this study explicates poverty and welfare attitudes as a product of social identities premised on subjective notions that are shaped by state discourses of meritocracy, self-reliance and anti-welfarism. It is thus argued that current socio-political constructions of poverty ensue a paucity of major welfare reform in the near future of Singapore.  相似文献   
58.
Children's conscience, including the ability to experience guilt and engage in rule‐compatible behavior, develops across early childhood. The current study investigated whether within‐family variation in children's baseline respiratory sinus arrhythmia (RSA) and sibling conflict behavior were associated with individual differences in children's guilt and internalized conduct. Between‐family differences across sibling dyad gender compositions were also examined. A within‐family design that included 70 families with two siblings between the ages of 2 and 5 was utilized. Children's baseline RSA was measured while sitting quietly with their family. Mothers and fathers completed questionnaires that assessed siblings’ conflict behavior, guilt, and internalized conduct. Older siblings had higher levels of guilt and internalized conduct than younger siblings. Results from actor‐partner interdependence models indicated that there were no direct effects of children's baseline RSA. The interaction effects approached significance (p's ≤ .08) suggesting that older siblings’ conflict moderated the association between older siblings’ baseline RSA and both older and younger siblings’ guilt. In contrast, older siblings’ conflict was positively associated with older and younger siblings’ internalized conduct. Guilt and internalized conduct also differed for older and younger siblings in different dyad gender compositions. The results underscore the need for greater clarity regarding the function that siblings serve in promoting children's moral development during early childhood.  相似文献   
59.
As medical and surgical advances improve, more young adults with congenital heart disease (CHD) are attending college. This case study illustrates some of the issues that these young adults may face as they attend college and discusses the role that college health practitioners can play in easing that transition. Participants: A case of a male with CHD presenting to the college health clinic with a new onset headache. Methods: The authors discuss some of the unique challenges that college health practitioners may face when caring for students with CHD. In addition, they make recommendations on how best to care for these patients and how best to coordinate care with CHD students other care providers. Results: This student with a history of coarctation of the aorta presented with new onset headaches and was found to have high blood pressure. He was diagnosed with recurrent coarctation, underwent percutaneous treatment with stenting and quickly resumed classes. Conclusions: As more students with CHD enter college, college health providers will need to understand some of the health risks that CHD students face. In addition, understanding some of the optimal ways to coordinate care with CHD providers can ease the transition that CHD students face as they enter college.  相似文献   
60.
Listeria monocytogenes is a leading cause of hospitalization, fetal loss, and death due to foodborne illnesses in the United States. A quantitative assessment of the relative risk of listeriosis associated with the consumption of 23 selected categories of ready‐to‐eat foods, published by the U.S. Department of Health and Human Services and the U.S. Department of Agriculture in 2003, has been instrumental in identifying the food products and practices that pose the greatest listeriosis risk and has guided the evaluation of potential intervention strategies. Dose‐response models, which quantify the relationship between an exposure dose and the probability of adverse health outcomes, were essential components of the risk assessment. However, because of data gaps and limitations in the available data and modeling approaches, considerable uncertainty existed. Since publication of the risk assessment, new data have become available for modeling L. monocytogenes dose‐response. At the same time, recent advances in the understanding of L. monocytogenes pathophysiology and strain diversity have warranted a critical reevaluation of the published dose‐response models. To discuss strategies for modeling L. monocytogenes dose‐response, the Interagency Risk Assessment Consortium (IRAC) and the Joint Institute for Food Safety and Applied Nutrition (JIFSAN) held a scientific workshop in 2011 (details available at http://foodrisk.org/irac/events/ ). The main findings of the workshop and the most current and relevant data identified during the workshop are summarized and presented in the context of L. monocytogenes dose‐response. This article also discusses new insights on dose‐response modeling for L. monocytogenes and research opportunities to meet future needs.  相似文献   
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