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31.
The cost of an uncontrolled incursion of invasive alien species (IAS) arising from undetected entry through ports can be substantial, and knowledge of port‐specific risks is needed to help allocate limited surveillance resources. Quantifying the establishment likelihood of such an incursion requires quantifying the ability of a species to enter, establish, and spread. Estimation of the approach rate of IAS into ports provides a measure of likelihood of entry. Data on the approach rate of IAS are typically sparse, and the combinations of risk factors relating to country of origin and port of arrival diverse. This presents challenges to making formal statistical inference on establishment likelihood. Here we demonstrate how these challenges can be overcome with judicious use of mixed‐effects models when estimating the incursion likelihood into Australia of the European (Apis mellifera) and Asian (A. cerana) honeybees, along with the invasive parasites of biosecurity concern they host (e.g., Varroa destructor). Our results demonstrate how skewed the establishment likelihood is, with one‐tenth of the ports accounting for 80% or more of the likelihood for both species. These results have been utilized by biosecurity agencies in the allocation of resources to the surveillance of maritime ports.  相似文献   
32.
War stories     
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33.
This study examines the relative importance of soft skills versus hard skills across occupations and its impact on the observed wage gap between Blacks and Whites in the United States. It posits that the Black/White pay gap may vary across occupations that require the use of different types of skills. We classify occupations into hard‐skill intensive versus soft‐skill intensive jobs using the skill content measures of different occupations from the Occupational Information Network (O*Net). We then use data from the National Longitudinal Survey of Youth (NLSY) and Current Population Survey (CPS) to investigate the impact of job skill type on the wage gap. Consistent with our theoretical predictions, we show that this wage gap in white‐collar jobs is smaller for hard‐skills jobs than it is for soft‐skills jobs. Moreover, we demonstrate that, in response to variations in the wage gap across different occupations, Blacks are more likely to self‐select themselves into hard‐skills jobs, ceteris paribus. This shows not only that discrimination against Blacks varies across occupations, but also that such discrimination induces the self‐selection of Blacks into certain occupations. Moreover, this finding highlights the role played by co‐worker/customer discrimination in explaining the racial wage gap in the U.S. labor market. (JEL J15, J31)  相似文献   
34.
The pursuit of operational excellence in the manufacturing industry is at rise but its measurement still lacks of appropriate indicators to determine its financial benefits. The ambiguity is due to the impact arisen from manufacturing fluctuations such as price and cost, production mix and direct and indirect parameters variations. Manufacturing fluctuations distort the cost benefit of operational excellence. This paper, therefore, proposes the OEP (Operational Excellence Profitability) indicators to isolate the impact of manufacturing fluctuation and distinctly identify the payback of operational excellence strategies and initiatives through cost benefits of achieving higher efficiency and yield. The paper presents the conceptual and mathematical development of the proposed OEP indicators and the formulas used for their calculation. Hypothetical and industrial-based investigations and applications of the OEP indicators are conducted for their validation. The results obtained from the hypothetical exercise and industrial case suggest that OEP indicators can provide an effective cost-benefit analysis of operational excellence. This would contribute in providing manufacturing organizations with more complete information regarding the performance of their processes, which will allow their directors and managers to take better decisions related to the management and improvement of their processes.  相似文献   
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36.
Review of Managerial Science - Third-party funding of academic research has grown rapidly in its scope and impact. However, several forces demand greater attention to potential opportunities,...  相似文献   
37.
Sea levels are rising in many areas around the world, posing risks to coastal communities and infrastructures. Strategies for managing these flood risks present decision challenges that require a combination of geophysical, economic, and infrastructure models. Previous studies have broken important new ground on the considerable tensions between the costs of upgrading infrastructure and the damages that could result from extreme flood events. However, many risk-based adaptation strategies remain silent on certain potentially important uncertainties, as well as the tradeoffs between competing objectives. Here, we implement and improve on a classic decision-analytical model (Van Dantzig 1956) to: (i) capture tradeoffs across conflicting stakeholder objectives, (ii) demonstrate the consequences of structural uncertainties in the sea-level rise and storm surge models, and (iii) identify the parametric uncertainties that most strongly influence each objective using global sensitivity analysis. We find that the flood adaptation model produces potentially myopic solutions when formulated using traditional mean-centric decision theory. Moving from a single-objective problem formulation to one with multiobjective tradeoffs dramatically expands the decision space, and highlights the need for compromise solutions to address stakeholder preferences. We find deep structural uncertainties that have large effects on the model outcome, with the storm surge parameters accounting for the greatest impacts. Global sensitivity analysis effectively identifies important parameter interactions that local methods overlook, and that could have critical implications for flood adaptation strategies.  相似文献   
38.
Introduction: We investigated if “thermobalancing” therapy (TT), using Dr Allen’s therapeutic device (DATD) in men with benign prostatic hyperplasia (BPH), can aid in understanding the etiology and pathophysiology of BPH.

Methods: We compared urinary and other parameters of BPH patients who received TT over 6 months (treatment group) with those of healthy volunteers who had not received the treatment (control group). Dynamics of symptoms and indicators in each group were evaluated in comparison with their data at the beginning and end of the study. Parameters were the International Prostate Symptom Score (IPSS) for urinary symptoms and quality of life (QoL), ultrasound measurement of prostate volume (PV) and uroflowmetry (maximum flow rate, Qmax). TT effectiveness was examined in 124 men with BPH and PV?<60?mL. We also investigated the data of five patients with BPH and PV?>60?mL.

Results: TT decreased urinary symptoms and PV, increased Qmax and improved QoL in men with BPH, PV?<60?mL, and in men with BPH, PV?>60?mL.

Conclusions: The present study demonstrated that TT is effective for BPH, suggesting that blood circulation plays a crucial role in its cause. The continuous heat exposure that does not exceed the normal body temperature terminates the trigger of BPH development, “micro-focus” of hypothermia, and the following spontaneous expansion of capillaries. TT could be considered to be a useful tool in BPH treatment.  相似文献   
39.
This article extends the previous research of consecutive attacks strategy by assuming that an attacker observes the outcome of each attack imperfectly. With given probabilities it may wrongly identify a destroyed target as undestroyed, and wrongly identify an undestroyed target as destroyed. The outcome of each attack is determined by a contest success function that depends on the amount of resources allocated by the defender and the attacker to each attack. The article suggests a probabilistic model of the multiple attacks and analyzes how the target destruction probability and the attacker's relative resource expenditure are impacted by the two probabilities of incorrect observation, the attacker's and defender's resource ratio, the contest intensity, the number of attacks, and the resource distribution across attacks. We analyze how the attacker chooses the number of attacks, the attack stopping rule, and the optimal resource distribution across attacks to maximize its utility.  相似文献   
40.
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