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161.
162.
Certain motor vehicle safety standards stipulate a collision test speed and a set of performance criteria that vehicles must satisfy during or after the collision test. For example, Federal Motor Vehicle Safety Standard 301 requires a 30 mile per hour (mph) barrier collision and specifies a certain maximum allowable limit on the total spillage of fuel. Vehicle designs are required to meet this standard; however, when collision tests are conducted at speeds higher than the standard, vehicles do not always satisfy the performance criteria. This paper develops a mathematical model for estimating the probability of meeting the standard by using a Bayesian framework to incorporate engineering judgment with collision test results. The model is based on the idea that there are random features to a vehicle's ability to meet performance standards in a collision, especially at such elevated speeds. Example calculations are included to illustrate the estimation of the probability of meeting the standard and to compare it with a maximum likelihood approach. 相似文献
163.
Ruthann Weaver Lariscy Elizabeth Johnson Avery Kaye D. Sweetser Pauline Howes 《Public Relations Review》2009,35(3):314-316
Using telephone surveys of business/financial journalists in the United States (n = 200), this research investigates the agenda-building role of social media content in journalists’ work. Understanding that more non-public relations content from user-generated and social network sites, like YouTube and Twitter, are fast becoming resources for journalists to get story ideas, break scandals, and find sources, we began this scholarly work to determine the frequency of such uses of social media. Overall, findings indicate very little use of social media by these business journalists. Results and implications for public relations practitioners are discussed in detail. 相似文献
164.
Our understanding of the underlying demographic components of population change in new Hispanic destinations is limited. In this paper, we (1) compare Hispanic migration patterns in traditional settlement areas with new growth in emerging Hispanic destinations; (2) examine the role of immigration vis‐à‐vis domestic migration in spurring Hispanic population redistribution; and (3) document patterns of migrant selectivity, distinguishing between in‐migrants and non‐migrant Hispanics at both the origin and destination. We use several recent datasets, including the 1990 and 2000 Public Use Microdata Samples (which include new regional geocodes), and the 2005 and 2006 files of the American Community Survey. Our results document the widespread dispersion of the Hispanic population over the 1990–2006 period from established Hispanic gateways into new Hispanic areas and other parts of the country. Nearly one‐half of Hispanic net migration in new destinations comes from domestic gains. In contrast, both established and other Hispanic areas depend entirely on immigration, with each losing domestic migrants to high growth areas. Migrant flows also are highly differentiated by education, citizenship, and nativity. To fully understand the spatial diffusion of Hispanics requires a new appreciation of the complex interplay among immigration, internal domestic migration, and fertility. 相似文献
165.
Corruption is a social ill that involves public officials’ misuse of entrusted power, which is a function of sociocultural factors. Rarely, however, do researchers view corruption as a leadership-related problem. In the current research, we conceptualize corruption as a leadership-related problem, and propose three broad leadership prototypes based on social value orientation theory and research. We seek to examine (1) how cultural endorsement of self-serving, prosocial, and individualistic leadership prototypes is related to corruption at the societal level and (2) how wealth moderates the relationship between cultural endorsement of self-serving leadership and corruption. Using archival data of 53 societies, we found that cultural endorsement of self-serving leadership was positively related to corruption, strengthened by wealth. Cultural endorsement of prosocial leadership and individualistic leadership, however, was not significantly related to corruption, and wealth did not moderate either of the relationships. The implications of these findings for theory and future research are discussed. 相似文献
166.
Evgeny D. Maslennikov Alexey V. Sulimov Igor A. Savkin Marina A. Evdokimova Dmitry A. Zateyshchikov Valery V. Nosikov 《Journal of applied statistics》2015,42(1):71-87
The article focuses on the application of the Bayesian networks (BN) technique to problems of personalized medicine. The simple (intuitive) algorithm of BN optimization with respect to the number of nodes using naive network topology is developed. This algorithm allows to increase the BN prediction quality and to identify the most important variables of the network. The parallel program implementing the algorithm has demonstrated good scalability with an increase in the computational cores number, and it can be applied to the large patients database containing thousands of variables. This program is applied for the prediction for the unfavorable outcome of coronary artery disease (CAD) for patients who survived the acute coronary syndrome (ACS). As a result, the quality of the predictions of the investigated networks was significantly improved and the most important risk factors were detected. The significance of the tumor necrosis factor-alpha gene polymorphism for the prediction of the unfavorable outcome of CAD for patients survived after ACS was revealed for the first time. 相似文献
167.
Roger J. Gagnon 《决策科学》1988,19(2):453-471
Teaching an operations design course has major pedagogical challenges. (1) The design topics—output, process, facility, and work design—are necessarily taught sequentially, yet the decisions are integrative. (2) Instruction must be generic to service or product producers. (3) Discussing output design is difficult since students typically have had no exposure to the “product language” of engineering graphics. (4) No text is available which examines in sufficient depth all the operations design decisions. (5) Cases necessarily depict historical situations—process technologies and economic data—while operations managers must plan future directions for their productive systems. (6) While the commercial world contains fresh information and data, students are inexperienced in obtaining knowledge from the real world. (7) While the course presents an operations management perspective, students must recognize the information, data, and cooperation necessary from the other functional areas to successfully complete the operations design. To help overcome these seven pedagogical challenges, the students in the undergraduate and graduate operation design courses complete a comprehensive feasibility study for a new product or service and the entire productive system. 相似文献
168.
Harvey J. Krahn Cher-Ann Chai Shichen Fang Nancy L. Galambos Matthew D. Johnson 《Journal of youth studies》2018,21(7):905-921
The transition from youth to adulthood in western societies has become more prolonged and complex as traditional societal norms have lost influence. Using retrospective data from a cohort of 43-year-old Canadians surveyed in 2010 (n?=?405), we mapped the timing, sequencing, and duration of ‘first stage’ youth-adult transitions (leaving home, finishing formal education, obtaining a full-time job) and ‘second stage’ youth-adult transitions (marriage, parenthood, home ownership). Latent profile analysis identified five distinct transition profiles – norm-setters, quick adults, uncertain adults, adult students, and delayed adults – with different amounts and timing of post-secondary educational investment playing an important profile-shaping role. Although youth-adult transitions have become less standardized and more individualized, especially for first stage transitions, these transitions are still quite structured and continue to be affected by gender and family socioeconomic status. 相似文献
169.
S. N. Rodda V. Manning N. A. Dowling S. J. Lee D. I. Lubman 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2018,34(1):307-320
Despite high rates of comorbidity between problem gambling and mental health disorders, few studies have examined barriers or facilitators to the implementation of screening for problem gambling in mental health services. This exploratory qualitative study identified key themes associated with screening in mental health services. Semi-structured interviews were undertaken with 30 clinicians and managers from 11 mental health services in Victoria, Australia. Major themes and subthemes were identified using qualitative content analysis. Six themes emerged including competing priorities, importance of routine screening, access to appropriate screening tools, resources, patient responsiveness and workforce development. Barriers to screening included a focus on immediate risk as well as gambling being often considered as a longer-term concern. Clinicians perceived problem gambling as a relatively rare condition, but did acknowledge the need for brief screening. Facilitators to screening were changes to system processes, such as identification of an appropriate brief screening instrument, mandating its use as part of routine screening, as well as funded workforce development activities in the identification and management of problem gambling. 相似文献
170.
Urban environments are often associated with reduced biodiversity, presumably because they are typically more fragmented, warmer, and drier than nearby non-urban environments. However, urban landscapes offer significant complexity that have allowed some taxonomic groups to flourish. Understanding how urban-exploiting animals navigate this spatiotemporal heterogeneity is important given the continued global urban land expansion. Here, we examined the factors influencing resource-use in an urban community of ants, which represent a widespread and important taxon in urban ecosystems. In particular, we sought to integrate ants’ nutritional, thermal, and spatial niches to better understand how urban animals successfully access critical resources throughout their active season. Meteorological season (spring, summer, and fall) and/or species (n?=?9) influenced ants’ preferences for nutrition (ratio of ingested protein-to-carbohydrate ratio), as well as the temperature, type (impervious vs. non-impervious), and shade status (shaded vs. non-shaded) of surfaces used during activity. Our data also indicate links among habitat variables, as well as between nutritional preferences and habitat use. Together, our results suggest that species and seasonality influence ecological (combined nutritional, thermal, and spatial) niches in an urban community. We encourage future work in urban ecosystems that continues to integrate more features of the ecological niche, and to examine the outcomes of variation in niches (e.g., non-overlapping niches may explain both the persistence of some native animals and the success of invaders). 相似文献