The role of terminators and occlusion cues in motion integration and segmentation: a neural network model

The perceptual interaction of terminators and occlusion cues with the functional processes of motion integration and segmentation is examined using a computational model. Inte-gration is necessary to overcome noise and the inherent ambiguity in locally measured motion direction (the aperture problem). Segmentation is required to detect the presence of motion discontinuities and to prevent spurious integration of motion signals between objects with different trajectories. Terminators are used for motion disambiguation, while occlusion cues are used to suppress motion noise at points where objects intersect. The model illustrates how competitive and cooperative interactions among cells carrying out these functions can account for a number of perceptual effects, including the chopsticks illusion and the occluded diamond illusion. Possible links to the neurophysiology of the middle temporal visual area (MT) are suggested

The Age Context of Performance Evaluation Decisions

Organizational demography contends that demographic characteristics of individuals, examined at individual, dyadic, group, and organizational levels of analysis, exert significant effects on organizational processes. The purpose of this paper was to test the contextual effects created by the interaction of work group age composition and supervisor age on supervisor evaluations of subordinate performance. Two competing models of age demography were tested. The similarity model predicts that supervisors similar in age to the work group they supervise will issue generally higher performance ratings. The dissimilarity model developed in this paper predicts the opposite. Support was indicated for the dissimilarity model. Implications of the results are discussed

V/STOL AND digital avionics system for UH-1H

A hardware and software system for the Bell UH-1H helicopter was developed that provides sophisticated navigation, guidance, control, display, and data acquisition capabilities for performing terminal area navigation, guidance and control research. Two Sperry 1819B general purpose digital computers were used. One contains the development software that performs all the specified system flight computations. The second computer is available to NASA for experimental programs that run simultaneously with the other computer programs and which may, at the push of a button, replace selected computer computations. Other features that provide research flexibility include keyboard selectable gains and parameters and software generated alphanumeric and CRT displays

V/STOLAND digital avionics system for XV-15 tilt rotor

A digital flight control system for the tilt rotor research aircraft provides sophisticated navigation, guidance, control, display and data acquisition capabilities for performing terminal area navigation, guidance and control research. All functions of the XV-15 V/STOLAND system were demonstrated on the NASA-ARC S-19 simulation facility under a comprehensive dynamic acceptance test. The most noteworthy accomplishments of the system are: (1) automatic configuration control of a tilt-rotor aircraft over the total operating range; (2) total hands-off landing to touchdown on various selectable straight-in glide slopes and on a flight path that includes a two-revolution helix; (3) automatic guidance along a programmed three-dimensional reference flight path; (4) navigation data for the automatic guidance computed on board, based on VOR/DME, TACAN, or MLS navid data; and (5) integration of a large set of functions in a single computer, utilizing 16k words of storage for programs and data

Controlled pilot development unit-scale fed-batch cultivation of yeast on spruce hydrolysates

Yeast production on hydrolysate is a likely process solution in large-scale ethanol production from lignocellulose. The hydrolysate will be available on site, and the yeast has furthermore been shown to acquire an increased inhibitor tolerance when cultivated on hydrolysate. However, due to over-flow metabolism and inhibition, efficient yeast production on hydrolysate can only be achieved by well-controlled substrate addition. In the present work, a method was developed for controlled addition of hydrolysate to PDU (process development unit)-scale aerobic fed-batch cultivations of Saccharomyces cerevisiae TMB 3000. A feed rate control strategy, which maintains the ethanol concentration at a low constant level, was adapted to process-like conditions. The ethanol concentration was obtained from on-line measurements of the ethanol mole fraction in the exhaust gas. A computer model of the system was developed to optimize control performance. Productivities, biomass yields, and byproduct formation were evaluated. The feed rate control worked satisfactorily and maintained the ethanol concentration close to the setpoint during the cultivations. Biomass yields of 0.45 g/g were obtained on added hexoses during cultivation on hydrolysate and of 0.49 g/g during cultivation on a synthetic medium with glucose as the carbon source. Exponential growth was achieved with a specific growth rate of 0.18 h(-1) during cultivation on hydrolysate and 0.22 h(-1) during cultivation on glucose

Perceptions of providing safe care for frail older people at home: A qualitative study based on focus group interviews with home care staff

Background: Providing safe care is a core competence in healthcare. The concept usually refers to hospitals but, consistent with the increasing importance of integrated care, the provision of safe care needs to be extended to the context of home care, and more research is needed concerning home healthcare providers’ perspectives in this context. Aim: The aim of this study was to describe care providers’ perceptions of providing safe care for frail older persons living at home. Method: A qualitative methodology was chosen. In total, 30 care providers agreed to participate. Data were collected through five focus group interviews and analysed using a phenomenographic approach. Results: Three themes regarding care providers’ perceptions of providing safe care emerged from the data: ‘safe care is created in the encounter and interaction with the older person’, ‘safe care requires responsibility from the caregiver’ and ‘safe care is threatened by insufficient organisational resources’. The findings show that providing safe care is an endeavour that requires a holistic view among the care providers as well as effective collaboration within the team, but insufficient competence or a lack of time can make it difficult to safeguard the psychological and existential needs of older persons. Conclusion: Providing safe care in home environments encompasses more than just risk reduction. The findings highlight the importance of establishing and integrating team-based and person-centred care into home care settings. Traditional communication structures for inpatient care also need to be adapted to the cross-disciplinary work in municipalities. Care providers should be given the opportunity to develop and maintain their competences and to prioritise relationship-oriented care

Negotiating Autonomy: girls and parental authority in multi-ethnic Norway. GARP10

Gender, equality and autonomy are key concepts in the discourse on multi-ethnicity in Norway, highlighting intergenerational relationships and processes of cultural continuity and change. In policy documents and in the media, debate on the integration of the relationship between parents and children has become the focal point, particularly with regard to how they practice autonomy and authority. The practices of ethnic minorities are compared with those of the ethnic majority, which are used as the standards of normal freedom and independency. However, the actual practice of autonomy and authority is taken for granted and seldom made clear. This paper explores what is involved in the process of becoming independent in contemporary Norway. It examines the sources of autonomy and how these are linked with the practice of parental authority through studies of four 15 year old girls growing up in a multi-ethnic neighbourhood in Oslo

What constitutes feeling safe at home? A qualitative interview study with frail older people receiving home care

Aim: To highlight experiences of what constitutes feeling safe at home among frail older people receiving home care. Design: Qualitative descriptive study. Methods: The sample consists of 12 individual recorded interviews with frail older people in their homes. Interviews were transcribed verbatim and analysed using qualitative content analysis. The data collection was performed in spring 2018. Results: The analysis resulted in three categories: "Having a feeling of\u27at-homeness\u27" describes the older people\u27s surrounding environment and their efforts to maintain independence; "being able to influence" describes the importance for older people to shape their care by being in control and having an opportunity for self-determination in the context of home care; and "being able to trust staff" relates to expecting staff\u27s knowledge and skills and to appreciating the staff\u27s ability to create positive relations

Mass Transport of Lignin in Confined Pores

A crucial step in the chemical delignification of wood is the transport of lignin fragments into free liquor; this step is believed to be the rate-limiting step. This study has investigated the diffusion of kraft lignin molecules through model cellulose membranes of various pore sizes (1-200 nm) by diffusion cells, where the lignin molecules diffuse from donor to acceptor cells through a membrane, where diffusion rate increases by pore size. UV-vis spectra of the donor solutions showed greater absorbance at higher wavelengths (similar to 450 nm), which was probably induced by scattering due to presence of large molecules/clusters, while acceptor samples passed through small pore membranes did not. The UV-vis spectra of acceptor solutions show a characteristic peak at around 350 nm, which corresponds to ionized conjugated molecules: indicating that a chemical fractionation has occurred. Size exclusion chromatography (SEC) showed a difference in the molecular weight (M-w) distribution between lignin from the donor and acceptor chambers. The results show that small pore sizes enable the diffusion of small individual molecules and hinder the transport of large lignin molecules or possible lignin clusters. This study provides more detail in understanding the mass transfer events of pulping processes