Повышение помехоустойчивости обработки сигналов в некогерентных радиолокационных системах

У роботі запропоновано новий підхід в побудові прийомопередавачів активних радіолокаційних систем, що передбачає використання паразитної модуляції радіолокаційних сигналів для підвищення когерентності та завадостійкості їх обробки за рахунок двохетапної обробки. Проведена аналітична оцінка потенційного виграшу в роздільній здатності імпульсних радіолокаційних систем з використанням даного методу. Приведено результати моделювання та дослідження отриманих виразів функцій невизначеності, які свідчать, що використання нестабільності передавача в якості додаткової модуляції дає змогу значно покращити роздільну здатність та завадостійкість радіолокаційної системи.Introduction. The work is devoted to the method of increasing coherence and noise immunity pulse radar systems with incoherent sources probing signals. Problem. Incongruities between a resolution and a range of pulsed radar systems can not be resolved within the classical approaches of building incoherent radar systems, requiring new approaches in their construction. The main part. The paper presents a method of two-stage processing incoherent pulsed radar signals, allowing to compensate and to use the information available to them and the angular amplitude of spurious modulation. Conclusions. Simulation results and research functions of these expressions of uncertainty indicate that use volatility as an additional transmitter modulation allows to improve significantly the resolution and robustness of the radar system.В работе предложен новый подход в построении приемопередатчиков активных радиолокационных систем, предусматривающий использование паразитной модуляции радиолокационных сигналов для повышения когерентности и помехоустойчивости их обработки, за счет двухэтапной обработки. Проведена аналитическая оценка потенциального выигрыша в разрешении импульсных радиолокационных систем с использованием данного метода. Приведены результаты моделирования и исследования полученных выражений функций неопределенности, которые свидетельствуют, что использование нестабильности передатчика в качестве дополнительной модуляции позволяет значительно улучшить разрешение и помехоустойчивость радиолокационной системы

The Virtual Solar Observatory: What Are We Up To Now?

In the nearly ten years of a functional Virtual Solar Observatory (VSO), http://virtualsolar.org/ we have made it possible to query and access sixty-seven distinct solar data products and several event lists from nine spacecraft and fifteen observatories or observing networks. We have used existing VSO technology, and developed new software, for a distributed network of sites caching and serving SDO HMI and/ or AlA data. We have also developed an application programming interface (API) that has enabled VSO search and data access capabilities in IDL, Python, and Java. We also have quite a bit of work yet to do, including completion of the implementation of access to SDO EVE data, and access to some nineteen other data sets from space- and ground-based observatories. In addition, we have been developing a new graphic user interface that will enable the saving of user interface and search preferences. We solicit advice from the community input prioritizing our task list, and adding to i

The genetic and phenotypic associations between lamb survival outcomes and other traits recorded at lambing

Context. Australian sheep breeding values (ASBVs) for lambing ease (LE) are estimated by Sheep Genetics, by using a threshold animal model at the lamb level, in a tri-variate analysis that includes data on birth weight, gestation length and lambing ease score. The implications of these traits for lamb survival, or the use of other indirect traits to improve accuracy of ASBVs for LE, are not currently being considered. Ultimately, it is desirable to extend the analysis to outcomes for individual lamb survival. Aim. The present study investigated implications of LE for lamb survival outcomes, accounting for litter size, and examined associations with other traits recorded at or shortly after lambing in maternal sheep breeds.Methods. Equivalent linear models were used to compare lamb- and ewe-level models with various combinations of additional random effects. In particular, lambing ease was treated as a different trait for single-born and twin-born lambs, to identify changes in genetic correlations associated with litter size between LE and other traits. Other traits included lambs recorded dead at birth, survival to weaning, lamb birth weight, gestation length and maternal behaviour score.Key results. Individual lamb survival outcomes inferred from field data and dead at birth lambs, are lowly heritable traits influenced by both direct and maternal effects. Lamb survival is positively correlated with birth weight, but negatively correlated with gestation length, lambing ease score (increasing lambing difficulty) and dead at birth lambs. Genetic and phenotypic correlations demonstrated that birth weight and lambing ease are antagonistic traits, more so for single-born lambs. Genetic correlations were moderate between dead at birth lambs and LE (0.40–0.45 singles; 0.15–0.36 including data from twins) or lamb survival (−0.63 to −0.81 singles; −0.00 to −0.23 including data from twins) and can add to the accuracy of genetic evaluation for these traits. In contrast, maternal behaviour score was predominantly an ewe trait, and will therefore add to accuracy of evaluation only for maternal effects. Lamb-level models appeared to underestimate heritability, sometimes compensated for by larger variance, and over-estimate genetic correlations for some traits relative to ewe-level models.Conclusions. Expanding the current lambing ease analysis to include dead at birth records and lamb survival outcomes would provide more detailed options for breeders to develop breeding goals to improve outcomes for both ewes and lambs. Further work is required to expand analyses to include threshold and continuous traits and understand genetic contributions to ewe survival traits.Implications. Relative selection emphasis on LE and birth weight must be considered in light of the expected litter size in which lambs will be born, to ensure favourable outcomes for lamb survival overall. Accuracy of genetic evaluation for LE can be improved using data on dead at birth. Equivalent ewe model analyses are possible. Completeness of pedigree, availability of informative lamb level data and integration with other traits are also factors to consider for the choice between operational lamb- versus ewe-level models for genetic evaluation systems

Reverse Monte Carlo modeling of amorphous silicon

An implementation of the Reverse Monte Carlo algorithm is presented for the study of amorphous tetrahedral semiconductors. By taking into account a number of constraints that describe the tetrahedral bonding geometry along with the radial distribution function, we construct a model of amorphous silicon using the reverse monte carlo technique. Starting from a completely random configuration, we generate a model of amorphous silicon containing 500 atoms closely reproducing the experimental static structure factor and bond angle distribution and in improved agreement with electronic properties. Comparison is made to existing Reverse Monte Carlo models, and the importance of suitable constraints beside experimental data is stressed.Comment: 6 pages, 4 PostScript figure

Controlled Release Spatial Repellent Devices (CRDS) as Novel Tools Against Malaria Transmission: A Semi-Field Study in Macha, Zambia

Background: The emergence of mosquitoes that can avoid indoor-deployed interventions, such as treated bed nets and indoor residual spraying, threatens the mainstay of malaria control in Zambia. Furthermore, the requirement for high coverage of these tools poses operational challenges. Spatial repellents are being assessed to supplement these vector control tools, but limitations exist in the residual effect of the repellent and the need for external power or heat for diffusion of the volatiles. Methods: A semi-field evaluation of a novel controlled release spatial repellent device (CRD) was conducted in Macha, Zambia. These devices emanate metofluthrin with no need for external power. Devices were deployed in huts within the semi-field system (SFS). Female Anopheles gambiae sensu stricto released within the SFS were trapped overnight by light traps and collected by aspiration the next morning inside and outside of huts to determine the extent of mosquito repellency and the impact on host-seeking and survival. Experiments studied the impact of number of devices as well as the presence of hut occupants. The study was complemented with numerical methods based on computational fluid dynamics to simulate spatial distribution of metofluthrin. Results: Presence of CRDs was associated with significant reductions in indoor counts of mosquitoes, regardless of whether huts were occupied or not. Repellency ranged from 15 to 60% compared to huts with no devices. Reducing the number of devices from 16 to 4 had little impact on repellency. When huts were occupied, indoor mosquito host-seeking was higher in the presence of CRDs, whilst survival was significantly reduced. Conclusions: This study demonstrated that deployment of as few as four CRDs within a hut was associated with reduced indoor mosquito densities. As would be expected, presence of occupants within huts, resulted in greater indoor catches (both with and without devices). The increased indoor mosquito host-seeking and mortality in huts when devices were present may be explained by the excito-repellency activity of metofluthrin. These semi-field experiments provide preliminary data on the utility of CRD spatial repellents to reduce indoor densities of An. gambiae mosquitoes. Studies will further investigate the impact of CRDs on mosquito behaviour as well as epidemiological protective efficacy

Mutuality of Rogers's therapeutic conditions and treatment progress in the first three psychotherapy sessions

Abstract Objective: Research on the effects of Rogers’s therapeutic relationship conditions has typically focused on the unilateral provision of empathy, unconditional positive regard, and congruence from therapist to client. Method: This study looked at both client and therapist mutuality of the Rogerian therapeutic conditions and the association between mutuality and treatment progress in the first three psychotherapy sessions. Clients (N = 62; mean age = 24.32; 77% female, 23% male) and therapists (N = 12; mean age = 34.32; nine female and three male) rated one another using the Barrett-Lennard Relationship Inventory after the first and third session. Results: Both clients and therapists perceived the quality of the relationship as improved over time. Client rating of psychological distress (CORE-OM) was lower after session 3 than at session 1 (es = .85, [95% CIs: .67, 1.03]). Hierarchical multiple regression was used to test the predictive power of mutually high levels of the therapeutic conditions on treatment progress. The association between client rating of therapist-provided conditions and treatment progress at session 3 was higher when both clients and therapists rated each other as providing high levels of the therapeutic conditions (R2 change = .073, p < .03). Conclusions: The findings suggest mutuality of Rogers’s therapeutic conditions is related to treatment progress. Keywords: therapeutic relationship; psychotherapy; mutuality; treatment progres