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271.
By building on a genetic‐inspired attribute‐based conceptual framework for safety risk analysis, we propose a novel approach to define, model, and simulate univariate and bivariate construction safety risk at the situational level. Our fully data‐driven techniques provide construction practitioners and academicians with an easy and automated way of getting valuable empirical insights from attribute‐based data extracted from unstructured textual injury reports. By applying our methodology on a data set of 814 injury reports, we first show the frequency‐magnitude distribution of construction safety risk to be very similar to that of many natural phenomena such as precipitation or earthquakes. Motivated by this observation, and drawing on state‐of‐the‐art techniques in hydroclimatology and insurance, we then introduce univariate and bivariate nonparametric stochastic safety risk generators based on kernel density estimators and copulas. These generators enable the user to produce large numbers of synthetic safety risk values faithful to the original data, allowing safety‐related decision making under uncertainty to be grounded on extensive empirical evidence. One of the implications of our study is that like natural phenomena, construction safety may benefit from being studied quantitatively by leveraging empirical data rather than strictly being approached through a managerial perspective using subjective data, which is the current industry standard. Finally, a side but interesting finding is that in our data set, attributes related to high energy levels (e.g., machinery, hazardous substance) and to human error (e.g., improper security of tools) emerge as strong risk shapers.  相似文献   
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The term gridlock describes the occurrence of rigid patterns in couples’ conflict. This study aimed to describe strategies of conflict resolution and gridlock prevention from the perspectives of couples and couple therapists. Participants were couple therapists and highly adjusted couples scored by the dyadic adjustment scale (DAS), distributed according to traditional and non‐traditional position in life and duration of relationships. Conflict gridlock scenarios were used to create video stimulus that were presented to participants. A qualitative methodology was used to analyse couples’ and therapists’ commentaries on the scenarios. Results showed differences in preventing conflict gridlock among sub‐groups of couples. Long‐term traditional couples focused on loyalty to a common project and value sacrificing to a higher good; long‐term non‐traditional couples prioritised caring and validating the bond in the relationship. Short‐term traditional couples focused on mutual love and the relief of hurt while short‐term non‐traditional couples supported the value of equity.  相似文献   
275.
It is well known that many industrial experiments have split‐plot structures. Compared to completely randomised experiments, split‐plot designs are more economical and thus have received much attention among researchers. Much work has been done for two‐level split‐plot designs. In this article, we consider split‐plot designs with factors of three, more than three, or mixed levels and with both qualitative and quantitative factors. We show that if two designs with both qualitative and quantitative factors are geometrically isomorphic, then their generalised wordlength patterns are identical. Three design scenarios are considered for optimal designs. The corresponding wordlength patterns are defined and the minimum aberration mixed‐level split‐plot designs having 18 and 36 runs are tabulated.  相似文献   
276.
This article provides a genealogy of the idea of an immigration industrial complex. The immigration industrial complex is the confluence of public and private sector interests in the criminalization of undocumented migration, immigration law enforcement, and the promotion of ‘anti‐illegal’ rhetoric. This concept is based on ideas developed with regard to the prison and military industrial complexes. These three complexes share three major features: (a) a rhetoric of fear; (b) the convergence of powerful interests; and (c) a discourse of other‐ization. This article explores why Congress has not passed viable legislation to deal with undocumented migration, and instead has passed laws destined to fail, and has appropriated billions of dollars to the Department of Homeland Security to implement these laws. This has been exacerbated in the context of the War on Terror, now that national security has been conflated with immigration law enforcement. This is the first in a two‐part series on the immigration industrial complex.  相似文献   
277.
Lead is a recognized neurotoxicant, but estimating effects at the lowest measurable levels is difficult. An international pooled analysis of data from seven cohort studies reported an inverse and supra‐linear relationship between blood lead concentrations and IQ scores in children. The lack of a clear threshold presents a challenge to the identification of an acceptable level of exposure. The benchmark dose (BMD) is defined as the dose that leads to a specific known loss. As an alternative to elusive thresholds, the BMD is being used increasingly by regulatory authorities. Using the pooled data, this article presents BMD results and applies different statistical techniques in the analysis of multistudy data. The calculations showed only a limited variation between studies in the steepness of the dose‐response functions. BMD results were quite robust to modeling assumptions with the best fitting models yielding lower confidence limits (BMDLs) of about 0.1–1.0 μ g/dL for the dose leading to a loss of one IQ point. We conclude that current allowable blood lead concentrations need to be lowered and further prevention efforts are needed to protect children from lead toxicity.  相似文献   
278.
In order to engage mothers who are victims of domestic abuse, the child welfare worker needs to be challenged to develop an intentional practice response that includes knowledge and skill concerning the complexities of domestic violence, as well as the process of change. Developing a supportive relationship, understanding the stages of change (SOC) and engaging mothers as leaders in the change process are essential to successful child protection outcomes. Within the context of the SOC model, this practice‐based paper focuses on the importance of engaging mothers who are victims of domestic violence in conversations about their own unique dilemmas, challenges and barriers regarding change. Through the inclusion of engagement strategies such as signs of safety, active listening and cost/benefit analysis, in concert with the SOC theory, the child welfare worker would be equipped with an approach to successfully assist mothers through their change journey, ultimately keeping children safe.  相似文献   
279.
When assessing risks posed by environmental chemical mixtures, whole mixture approaches are preferred to component approaches. When toxicological data on whole mixtures as they occur in the environment are not available, Environmental Protection Agency guidance states that toxicity data from a mixture considered “sufficiently similar” to the environmental mixture can serve as a surrogate. We propose a novel method to examine whether mixtures are sufficiently similar, when exposure data and mixture toxicity study data from at least one representative mixture are available. We define sufficient similarity using equivalence testing methodology comparing the distance between benchmark dose estimates for mixtures in both data‐rich and data‐poor cases. We construct a “similar mixtures risk indicator”(SMRI) (analogous to the hazard index) on sufficiently similar mixtures linking exposure data with mixtures toxicology data. The methods are illustrated using pyrethroid mixtures occurrence data collected in child care centers (CCC) and dose‐response data examining acute neurobehavioral effects of pyrethroid mixtures in rats. Our method shows that the mixtures from 90% of the CCCs were sufficiently similar to the dose‐response study mixture. Using exposure estimates for a hypothetical child, the 95th percentile of the (weighted) SMRI for these sufficiently similar mixtures was 0.20 (i.e., where SMRI <1, less concern; >1, more concern).  相似文献   
280.
This research project examined the individual and combined effectiveness of an HIV prevention workshop and a free condom distribution program in four high schools in Tijuana, Mexico. Adolescents (N = 320) completed baseline measures on sexual practices and theoretical correlates and participated in a two‐part study. In Study I, students were randomly assigned to an HIV prevention workshop or a control condition, with a 3‐month follow‐up assessment. Results indicate three significant workshop benefits regarding HIV transmission by altering sexual initiation, access to condoms, and traditional beliefs regarding condoms. In Study 2, we set up a condom distribution program at two of the participating schools, and students completed a 6‐month follow‐up assessment. Results indicate that exposure to the workshop followed by access to the condom distribution program yielded two beneficial results for reducing HIV transmission: moderating sexual initiation and increasing condom acquisition. Access to the condom distribution program alone had no effects on behavioral and psy‐chosocial correlates of HFV transmission. We discuss implications of these results.  相似文献   
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