P78-2 (SCATHA) satellite thermal balance test, a laboratory test

Space simulation test programs can be carried out with a high probability of being troublefree with a competent staff, a well-maintained test facility and attention to interfaces; however, full-up thermal balance tests using the solar simulator, temperature control of infrared sources, the gimbal, a large number of thermocouples, and other requirements for a high fidelity thermal balance are still a challenge. The P78-2 (Scatha) satellite was successfully tested with one interruption and a four-day abbreviated retest to verify a modification. This was accomplished in spite of the new test crew, a facility beset with several operational problems, and marginal interface control. These problems were addressed with very good results. Subsequent tests have been highly successful

Daytime ClO over McMurdo in September 1987: Altitude profile retrieval accuracy

During the 1987 National Ozone Expedition, mm-wave emission line spectra of the 278.6 GHz rotational stratospheric ClO were observed at McMurdo Station, Antarctica. The results confirm the 1986 discovery of a lower stratospheric layer with approximately 100 times the normal amount of ClO; the 1987 observations, made with a spectrometer bandwidth twice that used in 1986, make possible a more accurate retrieval of the altitude profile of the low altitude component of stratospheric ClO from the pressure broadened line shape, down to approximately 16 km. The accuracy of the altitude profile retrievals is discussed, using the daytime (09:30 to 19:30, local time) data from 20 to 24 September, 1987 as an example. The signal strength averaged over this daytime period is approx. 85 percent of the midday peak value. The rate of ozone depletion implied by the observed ClO densities is also discussed

Quantitative observations of the behavior of anomalous low altitude ClO in the Antarctic spring Stratosphere, 1987

During the second National Ozone Expedition ground-based observations at McMurdo Station Antarctica were performed which resulted in a second season's measurement of abnormally large amounts of ClO in the Antarctic spring stratosphere. The original measurements of 1986, in which the presence of this anomalous layer was first discovered, were limited in low altitude recovery of the ClO mixing ratio profile by the restrictions of the spectral bandwidth (256 MHz) which was used to measure the pressure-broadened ClO emission line shape. The 1987 measurements were marked by the use of twice the spectral bandpass employed the previous year, and allow a better characterization of the ClO mixing ratio profile in the critical altitude range 18 to 25 km. In-situ aircraft measurements of ClO made over the Palmer Peninsula during Aug. and Sept. of 1987 by Anderson, et al. effectively determined the important question of the ClO mixing ratio profile at altitudes inaccessible to our technique, below approximately 18 to 18.5 km. These flights did not penetrate further than 75 deg S, however, (vs 78 deg S for McMurdo) and were thus limited to coverage near the outer boundaries of the region of severest ozone depletion over Antarctica in 1987, did not reach an altitude convincingly above that of the peak mixing ratio for ClO, and were not able to make significant observations of the diurnal variation of ClO. The two techniques, and the body of data recovered by each, thus complement one another in producing a full picture of the anomalous ClO layer intimately connected with the region of Antarctic spring ozone depletion. An analysis is presented of the mixing ratio profile from approximately 18 to 45 km, the diurnal behavior, and the secular change in ClO over McMurdo Station during Sept. and early Oct. 1987

Operation of the SUPARAMP at 33GHz

A 9mm degenerate parametric amplifier was constructed using a linear, series array of unbiased Josephson junctions as the active, nonlinear element. A balanced diode mixer was used as a synchronous detector, with a single source serving both as the pump and as the mixer local oscillator. A stable, net gain of 15 dB in an instantaneous bandwith (FWHM) of 3.4 GHz was achieved. A system noise temperature of 220 K + or - 5 K (DSB) was measured with a SUPARAMP contribution of only 20 K x or - 10 K. Output saturation was observed and complicates the interpretation of the noise temperature measurements and may render them upper limits. A comparison was made with the results of an earlier 3 cm suparamp. The data is in substantial agreement with theoretical predictions

Inherent noise can facilitate coherence in collective swarm motion

Among the most striking aspects of the movement of many animal groups are their sudden coherent changes in direction. Recent observations of locusts and starlings have shown that this directional switching is an intrinsic property of their motion. Similar direction switches are seen in self-propelled particle and other models of group motion. Comprehending the factors that determine such switches is key to understanding the movement of these groups. Here, we adopt a coarse-grained approach to the study of directional switching in a self-propelled particle model assuming an underlying one-dimensional Fokker–Planck equation for the mean velocity of the particles. We continue with this assumption in analyzing experimental data on locusts and use a similar systematic Fokker–Planck equation coefficient estimation approach to extract the relevant information for the assumed Fokker–Planck equation underlying that experimental data. In the experiment itself the motion of groups of 5 to 100 locust nymphs was investigated in a homogeneous laboratory environment, helping us to establish the intrinsic dynamics of locust marching bands. We determine the mean time between direction switches as a function of group density for the experimental data and the self-propelled particle model. This systematic approach allows us to identify key differences between the experimental data and the model, revealing that individual locusts appear to increase the randomness of their movements in response to a loss of alignment by the group. We give a quantitative description of how locusts use noise to maintain swarm alignment. We discuss further how properties of individual animal behavior, inferred by using the Fokker–Planck equation coefficient estimation approach, can be implemented in the self-propelled particle model to replicate qualitatively the group level dynamics seen in the experimental data

Optical and Infrared Spectroscopy

Contains research objectives, summary of research and reports on four research projects.Joint Services Electronics Programs (U. S. Army, U.S. Navy, and U. S. Air Force) under Contract DA 28-043-AMC-02536(E)National Aeronautics and Space Administration (Grant NGR-22-009-237)U. S. Air Force Cambridge Research Laboratories Contract AF 19(628)-606

COMPOSITE SAMPLING TECHNIQUES FOR DETERMINING PESTICIDE CONCENTRATIONS

Composite sampling techniques are compared with random sampling methods for determining pesticide concentrations in agricultural fields. Estimates of mean pesticide concentrations and associated standard errors are presented for different experimental conditions. Variance components defined in extended forms of the Brown-Fisher model are estimated. The method of nonlinear least squares was employed to obtain numerical estimates of variance components by equating observed mean squares to expected mean squares for appropriate sampling designs

A critical analysis of the drivers of human migration patterns in the presence of climate change: A new conceptual model

Both climate change and migration present key concerns for global health progress. Despite this, a transparent method for identifying and understanding the relationship between climate change, migration and other contextual factors remains a knowledge gap. Existing conceptual models are useful in understanding the complexities of climate migration, but provide varying degrees of applicability to quantitative studies, resulting in non-homogenous transferability of knowledge in this important area. This paper attempts to provide a critical review of climate migration literature, as well as presenting a new conceptual model for the identification of the drivers of migration in the context of climate change. It focuses on the interactions and the dynamics of drivers over time, space and society. Through systematic, pan-disciplinary and homogenous application of theory to different geographical contexts, we aim to improve understanding of the impacts of climate change on migration. A brief case study of Malawi is provided to demonstrate how this global conceptual model can be applied into local contextual scenarios. In doing so, we hope to provide insights that help in the more homogenous applications of conceptual frameworks for this area and more generally

Brief Note Elemental Analysis of Biological Material in the Fresh-Frozen State

Author Institution: Department of Zoology and Department of Surgery, The Ohio State Universit