First year engineering mathematics: the London South Bank University experience

This short article describes an innovative approach to teaching mathematics to first year undergraduates on a variety of B. Eng. courses offered in the Faculty of Engineering, Science and Built Environment (FESBE) of London South Bank University (LSBU)

Condon Domain Phase Diagram for Silver

We present the Condon domain phase diagram for a silver single crystal measured in magnetic fields up to 28 T and temperatures down to 1.3 K. A standard ac method with a pickup coil system is used at low frequency for the measurements of the de Haas-van Alphen effect (dHvA). The transition point from the state of homogeneous magnetization to the inhomogeneous Condon domain state (CDS) is found as the point where a small irreversibility in the dHvA magnetization arises, as manifested by an extremely nonlinear response in the pickup voltage showing threshold character. The third harmonic content in the ac response is used to determine with high precision the CDS phase boundary. The experimentally determined Condon domain phase diagram is in good agreement with the theoretical prediction calculated by the standard Lifshitz-Kosevich (LK) formula

Scintillations effects on satellite to Earth links for telecommunication and navigation purposes

Radio wave scintillations are rapid fluctuations in both amplitude and phase of signals propagating through the atmosphere. GPS signals can be affected by these disturbances which can lead to a complete loss of lock when the electron density strongly fluctuates around the background ionization level at small spatial scales. This paper will present recent improvements to the theoretical Global Ionospheric Scintillation Model (GISM), particularly tailored for satellite based navigation systems such GPS coupled with Satellite Based Augmentation System (SBAS). This model has been improved in order to take into account GPS constellation, signals, and receiver response to ionospheric scintillation environments. A new modelling technique, able to describe the scintillation derived modifications of transionospheric propagating fields is shown. Results from GPS derived experimental measurements performed at high and low magnetic latitudes will show preliminary assessments of the scintillation impact on real receivers and system operations. Nevertheless, comparisons between theoretical scintillation models, such as WBMOD and GISM, with GPS derived experimental data will be shown

The efficiency of using the substrate technological module in the technology of growing potato mini-tubers

Known technologies and methods for obtaining virus-free potato mini-tubers of a required size fraction do not fully provide the highest multiplication factor, which occurs due to the insufficient productivity of an individual potato plant. On the basis of long-term experimental data (2012…2022), an assessment of the effectiveness of methods for growing potato mini-tubers in open and protected ground conditions is given. According to the number of tubers harvested from one plant, all growing methods can be divided into two large groups:  traditional (3-12 potatoes per plant) and modified (more than 40 potatoes per plant). A highly efficient method has been developed for obtaining mini-tubers of potatoes harvested as they grow on soil substrates with an average annual productivity of at least 50 mini-tubers from one micro-tuber and 40 mini-tubers from one virus-free plant (with traditional substrate methods – from 3 to 10 mini-tubers). Based on this method, there has been created a substrate technological module of a new generation harvesting tubers as they grow which makes it possible to obtain an average of 40 to 55 mini-tubers from one virus-free plant over the years, that is almost 10 times more in comparison with traditional methods of growing with a single harvest at the end of vegetation. Harvesting mini-tubers as they grow up to a required size creates the possibility of obtaining tubers of one size fraction (10-25 g), which allows later, when laying the nursery of the first field reproduction, to apply mechanized planting in the field and obtain uniform seedlings

Near-Earth space plasma modelling and forecasting

In the frame of the European COST 296 project (Mitigation of Ionospheric Effects on Radio Systems, MIERS)in the Working Package 1.3, new ionospheric models, prediction and forecasting methods and programs as well as ionospheric imaging techniques have been developed. They include (i) topside ionosphere and meso-scale irregularity models, (ii) improved forecasting methods for real time forecasting and for prediction of foF2, M(3000)F2, MUF and TECs, including the use of new techniques such as Neurofuzzy, Nearest Neighbour, Cascade Modelling and Genetic Programming and (iii) improved dynamic high latitude ionosphere models through tomographic imaging and model validation. The success of the prediction algorithms and their improvement over existing methods has been demonstrated by comparing predictions with later real data. The collaboration between different European partners (including interchange of data) has played a significant part in the development and validation of these new prediction and forecasting methods, programs and algorithms which can be applied to a variety of practical applications leading to improved mitigation of ionosphereic and space weather effects.Published255-2713.9. Fisica della magnetosfera, ionosfera e meteorologia spazialeJCR Journalope

Обоснование конструктивных требований к автоматизированному посадочному агрегату мини-клубней картофеля

The authors showed that the transition to the technology of virus-free minitubers mass production changed the machines requirements for planting original seed potatoes.(Research purpose) To develop a technological scheme and substantiate the design parameters of the planting apparatus of an automatic planter of potato minitubers.(Materials and methods) The development was based on an elevator-type planting apparatus. The authors decided to create a spoon design with the ability to grip and move into the guide casing one minituber in each spoon, eliminating the minitubers jumping from one spoon to another or pinching them when moving along the guiding casing to the furrow bottom. The diameters of the lower guide and upper drive rollers were theoretically substantiated in order to exclude the influence of the planting tubers sizes difference on the uniformity of their submitting into the furrow.(Results and discussion) The authors determined the minimum permissible elevator belt speed, which depended on the distance between the spoons on the elevator belt and the planting unit speed. The size of the upper driving reel diameter was justified from the condition that the spoon unfolded 180 degrees in at least 1.5 seconds, which ensured a tuber smooth transition to the back side of the spoon.(Conclusions) The authors developed a technological scheme of an automatic planting elevator type device for planting potato minitubers with a working speed of 6-9 kilometers per hour. It was found that the upper driving reel diameter was not less than 44 centimeters, and the lower guide roller diameter was not more than 12 centimeters. They showed that the double-sided design of scooping spoons with the possibility of installing replaceable bowls in them would ensure a high-quality planting of not only minitubers, but also subsequent reproductions of seed and ware potatoes with a tuber mass of 5-80 grams.Показали, что переход на технологии массового получения безвирусных мини-клубней меняет требования к машинам для посадки оригинального семенного картофеля.(Цель исследования) Разработать технологическую схему и обосновать конструктивные параметры высаживающего аппарата автоматической сажалки мини-клубней картофеля.(Материалы и методы) За основу разработки взяли высаживающий аппарат элеваторного типа. Решили создать конструкцию ложечки с возможностью захвата и перемещения в направляющий кожух по одному мини-клубню в каждой ложечке, исключив перескакивание мини-клубней с одной ложечки на другую или защемление их при перемещении по направляющему кожуху на дно борозды. Теоретически обосновали диаметры нижнего направляющего и верхнего ведущего роликов, чтобы исключить влияние разницы в размерах посадочных клубней на равномерность подачи их в борозду.(Результаты и обсуждение) Определили минимально допустимую скорость ленты элеватора, которая зависит от расстояния между ложечками на ленте элеватора и скорости посадочного агрегата. Размер диаметра верхнего ведущего барабана обосновали из условия разворачивания ложечки на 180 градусов не менее чем за 1,5 секунды, что обеспечивает плавный переход клубня на обратную сторону ложечки.Выводы. Разработали технологическую схему автоматического высаживающего аппарата элеваторного типа для сажалки мини-клубней картофеля с рабочей скоростью 6-9 километров в час. Выявили, что диаметр верхнего ведущего барабана не меньше 44 сантиметров, нижнего направляющего ролика – не более 12 сантиметров. Показали, что двусторонняя конструкция вычерпывающих ложечек с возможностью установки в них сменных чаш обеспечит качественную посадку не только мини-клубней, но и последующих репродукций семенного, а также продовольственного картофеля при массе клубней 5-80 граммов

Observation of strong final-state effects in pi+ production in pp collisions at 400 MeV

Differential cross sections of the reactions $pp \to d\pi^+$ and $pp \to pn\pi^+$ have been measured at $T_p = 400$ MeV by detecting the charged ejectiles in the angular range $4^0 \leq \Theta_{Lab} \leq 21^\circ$. The deduced total cross sections agree well with those published previously for neighbouring energies. The invariant mass spectra are observed to be strongly affected by $\Delta$ production and $NN$ final-state interaction. The data are well described by Monte Carlo simulations including both these effects. The ratio of $pp \to pn\pi^+$ and $pp \to d\pi^+$ cross sections also compares favourably to a recent theoretical prediction which suggests a dominance of $np$-production in the relative $^3S_1$-state.Comment: 17 pages, 5 figure

Near-Earth space plasma modelling and forecasting

In the frame of the European COST 296 project (Mitigation of Ionospheric Effects on Radio Systems, MIERS)in the Working Package 1.3, new ionospheric models, prediction and forecasting methods and programs as well as ionospheric imaging techniques have been developed. They include (i) topside ionosphere and meso-scale irregularity models, (ii) improved forecasting methods for real time forecasting and for prediction of foF2, M(3000)F2, MUF and TECs, including the use of new techniques such as Neurofuzzy, Nearest Neighbour, Cascade Modelling and Genetic Programming and (iii) improved dynamic high latitude ionosphere models through tomographic imaging and model validation. The success of the prediction algorithms and their improvement over existing methods has been demonstrated by comparing predictions with later real data. The collaboration between different European partners (including interchange of data) has played a significant part in the development and validation of these new prediction and forecasting methods, programs and algorithms which can be applied to a variety of practical applications leading to improved mitigation of ionosphereic and space weather effects

Higher Partial Waves in p+p->p+p+eta near Threshold

Exclusive measurements of the production of eta mesons in the p+p->p+p+eta reaction have been carried out at excess energies of 16 and 37 MeV above threshold. The deviations from phase space are dominated by the proton-proton final state interaction and this influences particularly the energy distribution of the eta meson. However, evidence is also presented at the higher energy for the existence of an anisotropy in the angular distributions of the eta meson and also of the final proton-proton pair, probably to be associated with D-waves in this system interfering with the dominant S-wave term. The sign of the eta angular anisotropy suggests that rho-exchange is important for this reaction.Comment: 16 pages, LaTeX2e, 3 EPS Figures, Updated version, Accepted for publication in Phys. Lett.

Scintillations effects on satellite to Earth links for telecommunication and navigation purposes

Radio wave scintillations are rapid fluctuations in both amplitude and phase of signals propagating through the atmosphere. GPS signals can be affected by these disturbances which can lead to a complete loss of lock when the electron density strongly fluctuates around the background ionization level at small spatial scales. This paper will present recent improvements to the theoretical Global Ionospheric Scintillation Model (GISM), particularly tailored for satellite based navigation systems such GPS coupled with Satellite Based Augmentation System (SBAS). This model has been improved in order to take into account GPS constellation, signals, and receiver response to ionospheric scintillation environments. A new modelling technique, able to describe the scintillation derived modifications of transionospheric propagating fields is shown. Results from GPS derived experimental measurements performed at high and low magnetic latitudes will show preliminary assessments of the scintillation impact on real receivers and system operations. Nevertheless, comparisons between theoretical scintillation models, such as WBMOD and GISM, with GPS derived experimental data will be shown