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Abstract

The aim of the study was to develop limit values for low microelement concentration in the soil, determined with the use of Mehlich 3 extractant for assessing their deficits in rapeseed crops. The values were prepared on the basis of 1944 fields with rapeseed, covering the whole Poland. In 2017, the samplers of Polish agro-chemical laboratories took soil samples and corresponding plant samples at the BBCH 30/31 stage. In the plant samples, the concentration of microelements was determined, and in the soil samples, apart from microelements, also pH, texture and the concentration of organic carbon and available phosphorus, were determined. Moreover, for each field, data on rapeseed yield were collected. Limit values were determined by two independent methods: 1) the method of regression equations and 2) the so-called high yield method. In the first case, the limit microelement concentration in the soil was calculated from the equation describing the relationship between the R/G bioaccumulation coefficient and a specific soil feature (n=1944). The bioaccumulation coefficient is a quotient of the concentration of a microelement in a plant (R) and its concentration in the soil determined by the Mehlich 3 (G) method. Limit values were calculated after substituting the critical concentration of microelements in the plant (R) to the equation, and subsequently, an appropriate conversion of the equation. The second method was based on the separation of a group of high yields ≥4.0 t ha−1 (n=755) from the whole data set. Then in this group, the lower quintiles (QU1) were calculated for the concentration of individual microelements in the soil determined in Mehlich 3 extract and adopted as limit values. It was found that QU1 is a good indicator of the lowest microelement concentration in the soil at which a yield of at least 4.0 t ha−1 can be obtained. The final limit values were worked out by averaging the values calculated by the equations and high yield method and their appropriate correction. In the combined soil sample collections for wheat and rapeseed (n=3865), the values were checked by evaluating the percentage of soils with microelement shortage separately for rape and wheat. The results of this evaluation were compared with the evaluation using the old system based on the 1 M HCl, which did not take into account the plant species.

Abstract

The construction of a water intake along the wharf shoreline can realise the intensive and comprehensive utilisation of the shoreline. However, since the water intake will increase the lateral flow at the wharf and also the hydrodynamic forces on ships, it will bring risks to ships mooring and leaving. The effects of the water intake on ships are studied using a physical model, numerical model and standard formulas. The results show that it leads to an increase of the hydrodynamic forces acting on the ship when the standard formulas are used to calculate the forces without considering the water level difference between the two sides of the ship. The results of the physical model are closer to the real situation. Measures that can effectively reduce the influence of the water intake on ships are proposed by increasing the distance between the wharf front and the front of the water intake as well as the depth of the water inlet windows.

Abstract

Tycho Brahe, noted Danish astronomer and founder of modern astronomy died in Prague in 1691, at the age of 54, and was buried in the Church of the Virgin Mary before Týn. In 2010, at the request of Danish authorities, his remains were exhumed and an investigation into the cause of his death was undertaken, with an aim to addressing speculations of him having been poisoned. This report contains detailed information on the process of the exhumation and results of the subsequent investigation. An anthropological analysis confirmed the authenticity of the remains, that they are actually those of Tycho Brahe, and confirmed the results of an earlier exhumation, done in 1901. Physical chemistry analysis was unable to confirm a lethal or sub-lethal dose of heavy metal poison (Hg). A detailed paleopathological analysis of the skeleton confirmed that Brahe suffered from DISH (diffuse idiopathic skeletal hyperostosis), which attends Type II diabetes, high blood pressure and obesity (the metabolic syndrome). From period documents describing Tycho Brahe’s lifestyle and his last days, it seems likely that he died of complications resulting from these conditions, today described as diseases of affluence, also referred to as “Western disease”.

Abstract

This paper examines the temporal dynamics of terrestrial mollusks of the Nikopol manganese ore basin technosols. The research was carried out at the Research Centre of the Dnipro Agrarian and Economic University in Pokrov (Ukraine). Sampling was carried out in 2012–2014 on four variants of artificial soil: formed on red-brown clays, on loess-like loams, on gray-green clays, and on humus-rich layer. The distribution of the number of individuals in a mollusk population was described by broken stick, Motomura, log-normal, Zipf, and Zipf-Mandelbrot models. It was shown that the series of models that best describe mollusk abundance distribution is specific for a particular species and technosols type and generally is invariant over time.

Abstract

The natural site of El-Mergueb, is one of the specific steppe ecosystem, that occupies an area of 16,481 ha; it is among the particular ecosystems in Algeria and is unique in northern Africa. It is located in the geographical limit of the Tell Atlas and the Saharan Atlas. It is at an altitude of 550 to 800 m, with a typically arid climate. The faunistic and floristic richness, quite specifically, contains species protected and classified in the IUCN: Chlamydotis and Gazella, as well as an autochthonous plant diversity: Stipa, Pistacia and Ziziphus. This study is based on the analysis of the vegetation by characterizing the associated soil type through the monitoring of the Eco-pedological relation during two seasons in three years: 2015−2016−2017. Nine soil profiles with a collection of twenty-one samples for each station of experimentation were collected. The results thus obtained showed that the content of the parameters analyzed is between low and average of the three stations. The average of the floristic analysis of the study area made it possible to define 34 botanical families spread over 69 botanical genus and 275 species. The analysis and the description of a natural space is important to establish a typology which is that is the basis for the development of management plans to conserve this category of protected areas. The FAC (Factorial Analysis of Correspondence) is relative to the individualization and the typology for three sequences, which corresponds to the groups (A), (B) and (C) also for the places in arid climate variants with very cold winters.

Abstract

This paper represents the first stage of research into a multi-objective method of planning safe trajectories for marine autonomous surface ships (MASSs) involved in encounter situations. Our method applies an evolutionary multi-objective optimisation (EMO) approach to pursue three objectives: minimisation of the risk of collision, minimisation of fuel consumption due to collision avoidance manoeuvres, and minimisation of the extra time spent on collision avoidance manoeuvres. Until now, a fully multi-objective optimisation has not been applied to the real-time problem of planning safe trajectories; instead, this optimisation problem has usually been reduced to a single aggregated cost function covering all objectives. The aim is to develop a method of planning safe trajectories for MASSs that is able to simultaneously pursue the three abovementioned objectives, make decisions in real time and without interaction with a human operator, handle basic types of encounters (in open or restricted waters, and in good or restricted visibility) and guarantee compliance with the International Regulations for Preventing Collisions at Sea. It should also be mentioned that optimisation of the system based on each criterion may occur at the cost of the others, so a reasonable balance is applied here by means of a configurable trade-off. This is done throughout the EMO process by means of modified Pareto dominance rules and by using a multi-criteria decision-making phase to filter the output Pareto set and choose the final solution

Abstract

The aim of the study was to assess the transformation of humic substances during composting of biomass of energetic plants and municipal solid waste. The type of the organic material to be composted and the type of technology used affect the course of the humic substances transformation and formation of compost maturity parameters. Compost produced from the mixture of energetic willow and hay biomass contained humic substances with higher share of low-molecular fractions and lower share of humic acids in total organic carbon than those produced from municipal solid wastes. Obtained results also showed that insoluble alkali fraction plays an important role in humification process by its convertion to a new humic substances. Share of humic and fulvic fractions in relation to the total organic carbon appears to be reliable indicator of composting as a process of enhancing organic matter humification.

Abstract

In the design process of offshore steel structures, it is typical to employ commercial calculation codes in which simulation and evaluation of results are performed on the basis of the available standards (e.g. API, DNV, Lloyds). The modeling and solution rely on finite element methods and cover the simulation of the structure’s properties along with the influence of the marine environment – sea currents, wave and wind loading, as well as the influence of vibrations, buoyancy and accompanying mass of water. Both commercial and open source mathematical modeling software which is available nowadays allows for cost effective and flexible implementation of advanced models for offshore industrial structures with high level of credibility and safety. The models can be built to suit task-specific requirements and evaluated on the basis of the selected criterial system best suited to the needs of the customer. Examples of methodology for environmental and structural model development are presented, along with simulation results covering a wide scope of data, ranging from stress and deformation to resonant characteristics and issues of technological feasibility.

Abstract

The statistics invariably show that most onboard fires originate in the engine room. In hazardous conditions, fires can spread to other rooms of the ship and cause the loss of human life, and can cause the ship to be out of service or lost completely. To prevent these serious consequences, the engine room crew should be aware of hazards and ways to prevent them. It is also advisable to support their routine activities and actions in critical situations with an appropriate management system.

For this reason, a survey was conducted at the beginning of 2019 of engine room crew members employed by a European shipowner, as a contribution to an analysis of fire safety management. Based on the results of the survey, some of the elements of the fire safety management system of the ship engine room are described. A properly constructed system that is understandable and accepted by the crew is one of the most important factors in increasing fire safety on a ship. Familiarisation with adequate procedures can significantly contribute to the successful prevention of accidents. This paper also proposes a checklist based on suggestions by the crew, which may be helpful in onboard fire prevention.