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61.
As the American imprisonment rate has risen, researchers have become increasingly concerned about the implications of mass imprisonment for family life. The authors extend this research by examining how paternal incarceration is linked to perceived instrumental support among the mothers of inmates' children. Results from the Fragile Families and Child Wellbeing Study (N = 4,132) suggest that recent, but not current, paternal incarceration is independently associated with less maternal perceived instrumental support and that this association persists after adjusting for a rich set of control variables, including prior perceived instrumental support. For families of recently incarcerated men, incarceration may be a double strike, simultaneously increasing the need for instrumental support while decreasing its availability when incarcerated fathers return to the community.  相似文献   
62.
We discuss a method of ranking allocations in economic environments which applies when we do not know the names or preferences of individual agents. We require that two allocations can be ranked with the knowledge only of agents present, their aggregate bundles, and community indifference sets—a condition we refer to as aggregate independence. We also postulate a basic Pareto and continuity property, and a property stating that when two disjoint economies and allocations are put together, the ranking in the large economy should be consistent with the rankings in the two smaller economies (reinforcement). We show that a ranking method satisfies these axioms if and only if there is a probability measure over the strictly positive prices for which the rule ranks allocations on the basis of the random-price money-metric utilitarian rule. This is a rule which computes the money-metric utility for each agent at each price, sums these, and then takes an expectation according to the probability measure.  相似文献   
63.
Recent energy and climate policies, particularly in the developed world, have increased demand for bioenergy2 as an alternative, which has led to both direct and indirect land-use changes and an array of environmental and socio-economic concerns. A comprehensive understanding of the land-use dynamics of bioenergy crop production is essential for the development of sustainable bioenergy and land-use policies. In this paper, we review the patterns and dynamics of land-use change associated with bioenergy crops (hereafter referred to as ’bioenergy-driven land-use change’). The review focuses on four regions as the most prominent locations in which these patterns and changes occur: Brazil; Indonesia and Malaysia; the United States of America (U.S.A.); and the European Union (EU). The review confirms that bioenergy-driven land-use change has affected and will impact most severely on the ’land- and resource-abundant’ developing regions, such as Brazil, where economic development takes priority over sustainable land-use policies, and the enforcement capability is limited. Opportunities for more effective policy are available through the development of international climate change policy (e.g. REDD under the UNFCCC), and certification criteria for sustainable bioenergy products (e.g. EU RED). However, bioenergy produced from no and/or less land-using feedstocks (e.g. wastes and residues), and their associated technologies must be given higher priority to minimise bioenergy-driven land-use change and its negative impacts.  相似文献   
64.
The fast aging of many western and eastern societies and their increasing reliance on information technology create a compelling need to reconsider older users' interactions with computers. This paper summarizes the results of 6 years of research on the age-differentiated design of human-computer interaction. The well-known model of human information processing served as the theoretical framework. The model components 'sensory processing', 'perception', 'working memory', 'decision and response selection' and 'response execution' were analyzed exemplarily in task settings on project management. In seven empirical studies with a total number of 405 participants between 20 and 77 years the human-computer interaction was analyzed regarding effectiveness, efficiency and user satisfaction. For most but not all studies the results reveal that age-induced differences in human-computer interaction can best be compensated by an ergonomic 'design for all'. In some cases however an age-specific approach is favorable.  相似文献   
65.
During employment of icons in order to represent system functions, specific user requirements from elderly people have not been scientifically gathered and thus will merely be considered during the process of system design. The survey, with explicit consideration of technology acceptance and experience of 120 elderly probands, looked into the comprehension of four different classes of non-animated graphical representations. It was shown that among elderly, the use of photos compared to pictograms or clip art leads to a significantly higher recognition rate. The mapping of actions rather than objects leads to a further reduction of the error probability and is thus, especially in the context of telemedicine, preferable for the target group.  相似文献   
66.
The numerical control of an experimental assembly cell with two robots--termed a cognitive control unit (CCU)--is able to simulate human information processing at a rule-based level of cognitive control. To enable the CCU to work on a large range of assembly tasks expected of a human operator, the cognitive architecture SOAR is used. The CCU can plan assembly processes autonomously and react to ad-hoc changes in assembly sequences effectively. Extensive simulation studies have shown that cognitive automation based on SOAR is especially suitable for random parts supply, which reduces planning effort in logistics. Conversely, a disproportional increase in processing time was observed for deterministic parts supply, especially for assemblies containing large numbers of identical parts. In this contribution, the effect of phase-shifts in deterministic part supply is investigated for assemblies containing maximal different parts. It can be shown that the concept of cognitive automation is as well suitable for these planning problems.  相似文献   
67.
Research has been done on the maximum reach and ingress/egress of upright seats. However, research on recumbent seats and comparisons between recumbent and upright seats is limited. By using an eight-camera Vicon motion capture system and C-motion Visual 3D modeling software, this research compared the ingress/egress joint kinematics and maximal planar reach of an upright seat with a recumbent seat. Mean range of motion and mean peak angle for each ingress/egress task were determined and the values for the upright seat were compared to the values for the recumbent seat. For each reach task, three extreme points were extracted and compared between the upright and recumbent seat. Seat orientation was found to have a statistically significant effect on the range of motion of several joints during the ingress/egress tasks, as well as one of the extreme points during the reaching tasks.  相似文献   
68.
Gerontolinguistic obtains a growing importance with the increase of elderly users due to Demographic Change. Since acceptance and ease of use of supportive systems for elderly, such as "E-Nursing-Assistants", are highly dependent on the age suitable design of readable instructions, an age-appropriate linguistic concept is of high value for usability. There has been only little research on the relevance of foreign words, signal words, textual arrangement, optical accentuation of key terms and temporal iconicity concerning older users. Thus, an efficient design of age suitable manual instructions within a medical context still remains to be done. The objective of this research was to evaluate the relevance of the previously mentioned factors in the context of written instructions. For this, an empirical survey was designed which was given to 45 study participants. The subjects of the experiment were given 4x3 instructions after a pretest questionnaire. The aim was to execute these instructions as correctly and quickly as possible. Furthermore the instructions were rated regarding comprehensibility with a retrospective questionnaire.  相似文献   
69.
The relationship between social insurance, which provides families protection against certain risks, and child economic security is understudied. Using the 2004 Survey of Income and Program Participation (SIPP) matched to Social Security Administration benefit records, this article investigates the economic welfare effects of the child component of the US Social Security program. We examine how the poverty rate of child beneficiaries would change, absent Social Security income, and how heavily the family incomes of these children rely on it, by family characteristics. Our findings reveal that Social Security plays an important role in mitigating economic insecurity among children deprived of a wage-earning parent through disability, death, or retirement. Family structure, earnings, and employment status are identified as key factors moderating the effect of Social Security on child recipients’ financial circumstance.  相似文献   
70.
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