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91.
The oil supply chain is facing new challenges due to emerging issues such as new alternative energy sources, oil sources scarcity, and price variability with high impact on demand and production and profit margins reduction. Additionally, the existence of large, complex and world wide spread businesses implies a complex system to be managed where distribution can be seen as one of the key areas that needs to be efficiently and effectively managed. Different types of distribution modes characterize the oil supply chain where the pipeline mode is one of the most complex to operate when having multiproduct characteristics. This paper addresses the planning of a generic oil derivatives transportation system characterized by a multiproduct pipeline that connects a single refinery to a storage tank farm. Two alternative mixed integer linear programming models (MILP) that aim to attain a set of planning objectives such as fulfilling costumers’ demands (which is mandatory) while minimizing the medium flow rate are developed. Additionally, final inventory levels are avoided to be excessively low. A real world scenario of a Portuguese company is used to validate and compare the two alternative MILP models developed in this paper.  相似文献   
92.
Public Organization Review - This exploratory qualitative case study analyzes the risks of misappropriation of COVID-19 relief funds managed by public agencies in the County of Los Angeles. This...  相似文献   
93.
VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - We examine whether third-party endorsement and institutional trust can mitigate the potential negative effects of higher...  相似文献   
94.
Path analysis was used to investigate the impact of childhood sexual abuse on later sexual victimization among 372 homeless and runaway youth in Seattle. Young people were interviewed directly on the streets and in shelters by outreach workers in youth service agencies. High rates of both childhood sexual abuse and street sexual victimization were reported, with females experiencing much greater rates compared with their male counterparts. Early sexual abuse in the home increased the likelihood of later sexual victimization on the streets indirectly by increasing the amount of time at risk, deviant peer affiliations, participating in deviant subsistence strategies, and engaging in survival sex. These findings suggest that exposure to dysfunctional and disorganized homes place youth on trajectories for early independence. Subsequently, street life and participation in high‐risk behaviors increases their probability of sexual victimization.  相似文献   
95.
This paper presents a study carried out in Spain that followed up 260 young people, the majority of them adults, who had been in residential care for significant periods. The follow‐up takes place between 1 and 9 years after participants had left residential care, and assesses their level of social and work integration, as well as considering the incidence of problems related to marginalization and social exclusion. Furthermore, it analyses the reasons for the child being taken into care, the socio‐family context, length of stay, changes in placement and other features or incidents in relation to the residential care. The data show that close to 15% have serious problems (drug dependence, delinquency, etc.), 25% receive help from the social services and the rest manage independently to a greater or lesser extent. We discuss the significance of these data, especially the relationship between the final result and the initial and process variables.  相似文献   
96.
Social Indicators Research - The aim of this paper is to shed some light on the behaviour of Inequality of Opportunity (IOp henceforth) in developing countries. The analysis is carried out using...  相似文献   
97.
Public Organization Review - This paper analyses direct management of COVID-19 in Brazil, Colombia and Peru, the three largest countries in the Western Amazon region. Using information gathered...  相似文献   
98.
The authors propose a new class of robust estimators for the parameters of a regression model in which the distribution of the error terms belongs to a class of exponential families including the log‐gamma distribution. These estimates, which are a natural extension of the MM‐estimates for ordinary regression, may combine simultaneously high asymptotic efficiency and a high breakdown point. The authors prove the consistency and derive the asymptotic normal distribution of these estimates. A Monte Carlo study allows them to assess the efficiency and robustness of these estimates for finite samples.  相似文献   
99.
This paper contributes to recent work examining the role of identity, and in particular the uses of language for self‐presentation and the expression of individual identity, through the analysis of two sociolinguistic interviews from a community of German origin in southern Brazil. Drawing from a quantitative study of variation in the southern state of Rio Grande do Sul, we conducted a detailed analysis of the interviews of two women of different ages and social backgrounds. We first describe the social, cultural and historical context of the interviews, and then discuss how our two speakers use their linguistic resources to express varied, and at times conflicting, aspects of their identities. More specifically, we show how our participants seem to maintain certain in‐group, German‐linked features, yet also use out‐group or Brazilian features in order to index both the (local) German and (regional) Brazilian aspects of their identities. Our data and analysis highlight how participants' identity and language use patterns can be better understood through close analysis of the content of their discourse.  相似文献   
100.
Resumen

Este estudio examina la relación entre apoyo social percibido, eventos vitales estresantes y depresión en una muestra (N = 74) perteneciente a la comunidad de Aranjuez. Como se hipotetizó, aparecen efectos directos significativos del apoyo social y de los eventos vitales sobre la depresión. Sin embargo no se obtuvieron efectos de interacción significativos, no apoyando nuestros resultados la hipótesis del efecto protector en el caso del apoyo social percibido. Este tipo de apoyo, en vez de simplemente proteger al individuo frente al impacto negativo del estrés, puede ser importante por sí mismo en la reducción de la sintomatologia depresiva.  相似文献   
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