Modifiability in behavior. I. Behavior of sea anemones

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The Birds of the Highlands of South-West Saudi Arabia and adjacent parts of the Tihama: July 2010

The objective of the survey was to compare habitats and bird life in the Asir region, particularly Jebal Souda and the Raydah escarpment protected area of the Saudi Wildlife Commission, and adjacent regions of the tihama, with those observed in July 1987 (Jennings, et al., 1988). The two surveys were approximately the same length and equal amounts of time were spent in the highlands and on the tihama. A number of walked censuses were carried out during 2010 on Jebal Souda, using the same methodology as walked censuses in 1987, and the results are compared. Broadly speaking the comparison of censuses revealed that in 2010 there were less birds and reduced diversity on the Jebal Souda plateau, compared to 1987. However in the Raydah reserve the estimates of breeding bird populations compiled in the mid 1990s was little changed as far as could be assessed in 2010. The highland region of south-west Saudi Arabia, especially Jebal Souda, has been much developed since the 1987 survey and is now an important internal recreation and resort area. This has lead to a reduction in the region’s importance for terraced agriculture. These changes may be a contributing factor to changes in bird numbers on the plateau. Subsidiary tasks that arose during the 2010 survey were to help locate satellite tagged Bald Ibises Geronticus eremita from Syria which were transiting Saudi Arabia at the time. Secondly to search for the Asir subspecies of the Eurasian Magpie Pica pica asirensis, which is endemic to the south-west Saudi Arabia highlands, and is reported to be in decline. A separate team searching for the Bald Ibis located some individuals and one was found dead. Few Magpies were located and it seems clear that this very scarce bird has declined further in numbers in recent years. A number of interesting records of birds were obtained, especially on the tihama, where two new birds for Saudi Arabia were observed, Black-headed Heron Ardea melanocephala and Painted Snipe Rostratula benghalensis and one species, Glossy Ibis Plegadis falcinellus was found breeding for the first time in the Arabian Peninsula. Some recommendations for the protection and management of the Raydah reserve are presented. A systematic list of all birds seen is provided

Determination of S17(0) from published data

The experimental landscape for the 7Be+p radiative capture reaction is rapidly changing as new high precision data become available. We present an evaluation of existing data, detailing the treatment of systematic errors and discrepancies, and show how they constrain the astrophysical S factor (S17), independent of any nuclear structure model. With theoretical models robustly determining the behavior of the sub-threshold pole, the extrapolation error can be reduced and a constraint placed on the slope of S17. Using only radiative capture data, we find S17(0) = 20.7 +/- 0.6 (stat) +/- 1.0 (syst) eV b if data sets are completely independent, while if data sets are completely correlated we find S17(0) = 21.4 +/- 0.5 (stat) +/- 1.4 (syst) eV b. The truth likely lies somewhere in between these two limits. Although we employ a formalism capable of treating discrepant data, we note that the central value of the S factor is dominated by the recent high precision data of Junghans et al., which imply a substantially higher value than other radiative capture and indirect measurements. Therefore we conclude that further progress will require new high precision data with a detailed error budget.Comment: 10 pages, 1 figure published versio

Taking Account of Non-Timber Values in Harvest Decisions in the Southern Forest of Tasmania

This paper examines the optimal use of a site containing standing timber, taking account of both timber and non-timber values. It discusses the range of non-timber values yielded by a typical site in the southern forest of Tasmania. Taking that site for illustrative purposes, it calculates the relationships between age of stand, extent of timber and non-timber values, and optimal cutting age, using a spreadsheet model. It finds that for a stand with moderate potential environmental benefits there is a period of its life during which it is optimal to log. This segment narrows, and eventually disappears, as potential environmental benefits increase

Cooperating Agents for 3D Scientific Data Interpretation

Many organizations collect vast quantities of three-dimensional (3-D) scientific data in volumetric form for a range of purposes, including resource exploration, market forecasting, and process modelling. Traditionally, these data have been interpreted by human experts with only minimal software assistance. However, such manual interpretation is a painstakingly slow and tedious process. Moreover, since interpretation involves subjective judgements and each interpreter has different scientific knowledge and experience, formulation of an effective interpretation often requires the cooperation of numerous such experts. Hence, there is a pressing need for a software system in which individual interpretations can be generated automatically and then refined through the use of cooperative reasoning and information sharing. To this end, a prototype system, SurfaceMapper, has been developed in which a community of cooperating software agents automatically locate and display interpretations in a volume of 3-D scientific data. The challenges and experiences in designing and building such a system are discussed. Particular emphasis is given to the agents' interactions and an empirical evaluation of the effectiveness of different cooperation strategies is presented

CCSDS Advanced Orbiting Systems Virtual Channel Access Service for QoS MACHETE Model

To support various communications requirements imposed by different missions, interplanetary communication protocols need to be designed, validated, and evaluated carefully. Multimission Advanced Communications Hybrid Environment for Test and Evaluation (MACHETE), described in "Simulator of Space Communication Networks" (NPO-41373), NASA Tech Briefs, Vol. 29, No. 8 (August 2005), p. 44, combines various tools for simulation and performance analysis of space networks. The MACHETE environment supports orbital analysis, link budget analysis, communications network simulations, and hardware-in-the-loop testing. By building abstract behavioral models of network protocols, one can validate performance after identifying the appropriate metrics of interest. The innovators have extended the MACHETE model library to include a generic link-layer Virtual Channel (VC) model supporting quality-of-service (QoS) controls based on IP streams. The main purpose of this generic Virtual Channel model addition was to interface fine-grain flow-based QoS (quality of service) between the network and MAC layers of the QualNet simulator, a commercial component of MACHETE. This software model adds the capability of mapping IP streams, based on header fields, to virtual channel numbers, allowing extended QoS handling at link layer. This feature further refines the QoS v existing at the network layer. QoS at the network layer (e.g. diffserv) supports few QoS classes, so data from one class will be aggregated together; differentiating between flows internal to a class/priority is not supported. By adding QoS classification capability between network and MAC layers through VC, one maps multiple VCs onto the same physical link. Users then specify different VC weights, and different queuing and scheduling policies at the link layer. This VC model supports system performance analysis of various virtual channel link-layer QoS queuing schemes independent of the network-layer QoS systems

The control parametrization enhancing transform for constrained time--delayed optimal control problems

The Control Parametrization Enhancing Technique (CPET), is extended to a general class of constrained time-delayed optimal control problems. A model transformation approach is used to convert the time-delayed problem to an optimal control problem involving mixed boundary conditions, but without time-delayed arguments. The CPET is then used to solve this non delayed problem. Two test examples have been solved to illustrate the efficiencies of the CPET for time delayed problems

Systematic Analysis Method for Color Transparency Experiments

We introduce a data analysis procedure for color transparency experiments which is considerably less model dependent than the transparency ratio method. The new method is based on fitting the shape of the A dependence of the nuclear cross section at fixed momentum transfer to determine the effective attenuation cross section for hadrons propagating through the nucleus. The procedure does not require assumptions about the hard scattering rate inside the nuclear medium. Instead, the hard scattering rate is deduced directly from the data. The only theoretical input necessary is in modelling the attenuation due to the nuclear medium, for which we use a simple exponential law. We apply this procedure to the Brookhaven experiment of Carroll et al and find that it clearly shows color transparency: the effective attenuation cross section in events with momentum transfer $Q^2$ is approximately $40\ mb\ (2.2\ GeV^2/Q^2)$. The fit to the data also supports the idea that the hard scattering inside the nuclear medium is closer to perturbative QCD predictions than is the scattering of isolated protons in free space. We also discuss the application of our approach to electroproduction experiments.Comment: 11 pages, 11 figures (figures not included, available upon request), report # KU-HEP-92-2