1,472 research outputs found
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Avoiding Future Famines: Strengthening the Ecological Foundation of Food Security through Sustainable Food Systems. A UNEP Synthesis Report
A piloted simulator study on augmentation systems to improve helicopter flying qualities in terrain flight
Four basic single-rotor helicopters, one teetering, on articulated, and two hingeless, which were found to have a variety of major deficiencies in a previous fixed-based simulator study, were selected as baseline configurations. The stability and control augmentation systems (SCAS) include simple control augmentation systems to decouple pitch and yaw responses due to collective input and to quicken the pitch and roll control responses; SCAS of rate-command type designed to optimize the sensitivity and damping and to decouple the pitch-roll due to aircraft angular tate; and attitude-command type SCAS. Pilot ratings and commentary are presented as well as performance data related to the task. SCAS control usages and their gain levels associated with specific rotor types are also discussed
Effects of rotor parameter variations on handling qualities of unaugmented helicopters in simulated terrain flight
A coordinated analysis and ground simulator experiment was performed to investigate the effects on single rotor helicopter handling qualities of systematic variations in the main rotor hinge restraint, hub hinge offset, pitch-flap coupling, and blade lock number. Teetering rotor, articulated rotor, and hingeless rotor helicopters were evaluated by research pilots in special low level flying tasks involving obstacle avoidance at 60 to 100 knots airspeed. The results of the experiment are in the form of pilot ratings, pilot commentary, and some objective performance measures. Criteria for damping and sensitivity are reexamined when combined with the additional factors of cross coupling due to pitch and roll rates, pitch coupling with collective pitch, and longitudinal static stability. Ratings obtained with and without motion are compared. Acceptable flying qualities were obtained within each rotor type by suitable adjustment of the hub parameters, however, pure teetering rotors were found to lack control power for the tasks. A limit for the coupling parameter L sub q/L sub p of 0.35 is suggested
Developing Socially Responsible Leadership and Social Perspective-Taking in Fraternities and Sororities: Findings From a National Study
Using data from the 2009 Multi-Institutional Study of Leadership, this study examines socially responsible leadership and social perspective-taking capacities disaggregated by council membership. Results show small but significant differences in developing these capacities. Implications for fraternity and sorority life professionals are discussed
Blue harvest: inland fisheries as an ecosystem service
Global food production has increased greatly in recent years and rural livelihoods are much improved in many regions. Yet, despite this clear progress rural poverty and food insecurity remain deeply entrenched in many areas, especially in South Asia and sub-Saharan Africa. In response the international community has renewed calls for increased commitment to meeting the needs of the world's poor. This report, commissioned as a contribution to the 10th Conference of the Parties to the Convention on Biological Diversity taking place in Nagoya, Japan, not only underlines the value of freshwater fisheries but provides guidance on how the ecosystem approach can be applied in order to sustain future harvests.Inland fisheries, Nutrition, Food security, Sustainability, Ecosystems
The Role of Social Perspective-Taking in Developing Students\u27 Leadership Capacities
This study examined relationships between social perspective-taking (SPT) and the individual, group, and societal domains of socially responsible leadership. SPT is a higher-order cognitive skill linked to moral development and social coordination, but never empirically connected to leadership development. Analyses determined SPT has a strong direct effect on group-level leadership values and an indirect effect on societallevel leadership values. Results offer critical new insights into directionality in the social change model
Quality of life and well-being of carers of people with dementia: are there differences between working and nonworking carers? Results from the IDEAL program
The aim of this study was to identify the differences in quality of life (QoL) and well-being between working and nonworking dementia carers and the relative contribution of psychological characteristics, caregiving experience, and social support. Multiple regressions modeled the contribution of working status, caregiver experiences, and psychological and social resources to carer QoL (EQ-5D) and well-being (WHO-5). After controlling for age, gender, carer–dyad relationship, and severity of dementia, working status contributed significant variance to EQ-5D (2%) but not to WHO-5 scores. Independent of working status, higher self-esteem and reduced stress contributed to variance in both models. Self-efficacy, social support, and positive perceptions of caregiving additionally contributed to higher WHO-5 scores. Working status associated with higher EQ-5D QoL; this may reflect the sustained sense of independence associated with supported work opportunities for carers. Outside of working status, the findings support the importance of psychological and social factors as targets to improved mental health for dementia carers
Water requirements of floodplain rivers and fisheries: existing decision support tools and pathways for development
Fisheries / Rivers / Flood plains / Hydrology / Ecology / Models / Decision support tools / Environmental impact assessment / Methodology / Databases
Using theory of change to achieve impact in AAS
The CGIAR Strategy and Results Framework sets out four system level outcomes (SLOs), namely: reducing rural poverty, improving food security, improving nutrition and health and sustainable management of natural resources. In pursuit of these objectives the CGIAR has developed a set of sixteen CGIAR Research Programs (CRPs), each of which is expected to make specific contributions to a range of intermediate development outcomes (IDOs) linked to the SLOs. As part of this work the CRPs are developing impact pathways and theories of change designed to explain how the programs will achieve IDOs. The purpose of the present paper is to explain the approach that the CRP on Aquatic Agricultural Systems (AAS) is taking to using these programmatic tools to help achieve impact
Anomalous Mediated SUSY Breaking, Fermion Masses and Natural Suppression of FCNC and CP Violating Effects
We construct realistic supergravity models where supersymmetry breaking
arises from the -terms of an anomalous gauge symmetry broken at the
Planck scale. The model has the attractive feature that the gaugino masses, the
and terms and the mass splittings between the like-charged squarks of
the first two generations compared to their average masses are all suppressed.
As a result, the electric dipole moment of the neutron as well as the flavor
changing neutral current effects are predicted to be naturally small. These
models predict naturally the expected value of the -term and also have the
potential to qualitatively explain the observed mass hierarchy among quarks and
leptons.Comment: Some references adde
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