Active cooling from the sixties to NASP

Vehicles, such as the X-15 or National Aero-Space Plane, traveling at hypersonic speeds through the earth's atmosphere experience aerodynamic heating. The heating can be severe enough that a thermal protection system is required to limit the temperature of the vehicle structure. Although several categories of thermal protection systems are mentioned briefly, the majority of this paper describes convectively cooled structures for large areas. Convective cooling is a method of limiting structural temperatures by circulating a coolant through the vehicle structure. Efforts to develop convectively cooled structures during the past 30 years--from early engine structures, which were intended to be tested on the X-15, to structural--are described. Many of the lessons learned from these research efforts are presented

Conflict resolution and policy making mediation in the Mekong River Basin

The Mekong River serves China, Myanmar, Thailand, Laos, Cambodia and Vietnam covering an area of approximately 795, 000 square kilometres and the Mekong River basin is a delicate eco-system rich in natural resources and bio-diversity. Competing demands for increasingly scarce supplies of water, the reciprocal impacts of land and water uses and inadequate governance arrangements have given rise to conflicts that has to be resolved by policy making to facilitate a process, whereby the main principles adopted in the Mekong River Agreement can be implemented.<br /

Conflict resolution and sustainable water use in the Mekong River Basin

In this paper it is argued that increased demands for water use in the Mekong River Basin makes this region vulnerable to conflict. Strategies to both prevent and manage conflict are necessary for sustainable water use in this region. Community development is integral to sustainable development. Community development strategies are particularly useful in recognising knowledge and expertise within local communities. They also assist in involving local communities - particularly members of minority groups in collaborative efforts for sustainable natural resource use and conflict management. It is essential that local communities are active partners in the development of conflict resolution and sustainable development strategies. Active and meaningful participation of local communities in the planning, and management of local water use development activities will increase the likelihood of sustainable outcomes.<br /

Pictures of complete positivity in arbitrary dimension

Two fundamental contributions to categorical quantum mechanics are presented. First, we generalize the CP-construction, that turns any dagger compact category into one with completely positive maps, to arbitrary dimension. Second, we axiomatize when a given category is the result of this construction.Comment: Final versio

Forest Fire Effects on Landscape Snow Albedo Recovery and Decay

Surface snow albedo (SSA) darkens immediately following a forest fire, while landscape snow albedo (LSA) brightens as more of the snow-covered surface becomes visible under the charred canopy. The duration and variability of the post-fire snow albedo recovery process remain unknown beyond a few years following the fire. We evaluated the temporal variability of post-fire snow albedo recovery relative to burn severity across a chronosequence of eight burned forests burned from 2000 to 2019, using pre- and post-fire daily, seasonal, and annual landscape snow albedo data derived from the Moderate Resolution Imaging Spectroradiometer (MOD10A1). Post-fire annual LSA increased by 21% the first year following the fire and increased continually by 33% on average across all eight forest fires and burn severity classifications over the period of record (18 years following a fire). Post-fire LSA measurements increased by 63% and 53% in high and moderate burn severity areas over ten years following fire. While minimum and maximum snow albedo values increased relative to annual post-fire LSA recovery, daily snow albedo decay following fresh snowfall accelerated following forest fire during the snowmelt period. Snow albedo recovery over 10 years following fire did not resemble the antecedent pre-fire unburned forest but more resembled open meadows. The degradation of forest canopy structure is the key driver underlying the paradox of the post-fire snow albedo change (SSA vs. LSA)

Farmers groups within extension networks in Northern Uganda : inclusive or exclusive?

Group extension methods are widely recognized as the most effective extension method in agricultural development internationally. Research in this area tends to look at group function, and factors that inhibit or promote successful group activity. Most development projects start with an analysis of whether groups exist or may need to be formed, and then focus on group function. However, very little research to date has considered the farmer group from a whole community context, when assessing knowledge and information dissemination in rural areas. This paper presents and discusses research finding from a case study with three communities in Gulu district of Northern Uganda, where household surveys were used to map networks within andbetween community members and external organizations identified as promoting agricultural development in the region. The potential impact of inclusion or exclusion in such a group within small communities emerged as a significant issue, as well as the strong disconnect between community and external organizational perceptions of group existence, function and impact.<br /

Working with farmers for better agriculture in Timor Leste

Agricultural production in Tirnor Leste is of vital importance, both for the majority of the population who rely primarily on agricultural production for their livelihoods, but also in the broader development agenda of this new nation. The post independence lack of public agricultural extension and the destruction of much the resource base led to the current situation whereby the NGO sector is the primary provider of advice, extension and access to resources for agricultural production. The very recent move to invest once more in public agricultural extension services provides a timely point to assess the role, approach, issues and opportunities faced by NGOs. This research is based on discussions with a number of NGO personnel, both local, national and international and raises a number of questions regarding how the wide variety of organisations engage with communities, their objectives, inputs, coverage, and impacts. The discussion is framed by an analysis of the changing practices in agricultural extension and the associated role of NGOs, and questions how best the agricultural sector rnight move forward in providing appropriate support to the farmers of Timor Leste..<br /

750 Papua New Guineas in Search of a Literature

In 1970 the prestigious A.N .Z.A.A.S. Conference was held in Port Moresby. To mark this occasion each delegate was given a publication put out by Collins, Longman and prepared, in the main, by staff of the University of Papua New Guinea. Perhaps because it abounds in maps, the editors called it an atlas. It is crammed with fascinating statistics about the then emerging nation. By the date of publication over 750 distinct languages had been identified, which implies over 750 different cultural groups. Superimposed on these culture groups were the spiritual and material expatriate cultures of eight major christian missions and an uncountable number of minor sects. At one stage these mission groups claimed the adherence of something like 92% ofthe population. What kind of adherents and what were their purposes was not questioned. Peter Lawrence in Road Belong Cargo develops the well documented theme that imported christianity simply reinforced and modemised existing local religions with disastrous results in the case of the Rai coast indigenes who form the subject of his book. We can hardly view christianity as a unifying cultural force through cargo cultism, though the cult of cargo is still a major area of concern to govemment and missions alike

Active cooling from the sixties to NASP

Vehicles, such as the X-15 or the National Aerospace Plane (NASP), traveling at hypersonic speeds through the earth's atmosphere experience aerodynamic heating. The heating can be severe enough that a thermal protection system is required to limit the temperature of the vehicle structure. Although several categories of thermal protection systems are mentioned briefly, the majority of the present paper describes convectively cooled structures for large areas. Convective cooling is a method of limiting structural temperatures by circulating a coolant through the vehicle structure. Efforts to develop convectively cooled structures during the past 30 years, from early engine structures which were intended to be tested on the X-15 to structural panels fabricated and tested under the NASP program, are described. Many of the lessons learned from these research efforts are presented