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Number of results: 11
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Abstract

Integration of transport subsystems in transfer nodes of public transport in Poznań based on city railway stations, Poznań, being one of the strongest urban centers in the country, has a significant zone of impact (functional area). A natural consequence of this development model are significant communication issues caused by dynamic development of the suburban area. The solution of those issues is assumed to be basing the public communication system on a railway junction and, on its basis, creating the Poznań Metropolitan Railway. However, to ensure efficient functioning of such a system the need arises to integrate it with other systems of transport using transfer nodes. The aim of this article is to illustrate the potential of creating a polycentric system of multi-modal transfer nodes, based on existing city railway stations (district stations). The study focuses on the perspective of the passenger and the primary research method is the in-depth interview. This enabled to learn the opinion and identify the needs of passengers who use the facilities which are the subject of this study. The study also concentrated on analyzing thee communication behaviors of passengers and analyzing thee functioning of city stations themselves. Additionally, information was also acquired regarding the approximate destination of the passengers’ travel, which further allowed to specify the hypothetical impact range of individual city stations. Results of the study allowed to develop a range of recommendations intended to optimize the functioning of selected city railway stations, from a technical, as well as organization and management perspective. They have the potential to become a basis for developing a concept of sustainable public transport with a metropolitan reach.
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Abstract

The article describes the work of the seaport transport-technological system (TTS). Spend controlling analysis of the basic processes and port operations. It was found that the construction of an optimal system of controlling processes, leading to increased efficiency of the port. We consider a variety of factors that affect the efficiency of the port of reloading works and the importance of quality of work at every stage of the process. In order to determine the level of the expected impact of controlling the use of the analysis of the construction of the port of the quality management system, which is taken as a basis for the organization of transport and technological system of the port as a whole. It determined that the efficiency depends on the turnover of the port and thus the quality and quantity of treated vessels. At the same time your system needs to build their own port, to meet the requirements of customers, and dependence of the amount processed by the courts from time to time is the reciprocal of. The authors propose a model of controlling the transport and port system technology, taking into account factors that affect the process efficiency. The scheme of internal communication processes, transport and port systems technology, as well as take into account the external communication with customers. Use of risk systems in the port processes allows us to consider its bottlenecks, and provide impact of pointing it to a particular element of the system, when it is needed, that is applicable to many processes, owls, and is a universal method to increase the efficiency of the enterprise.
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Abstract

Transport is one of the factors influencing the development of metropolitan areas. However, for its efficient work, numerous optimizations are required. Main tasks are shortening travel time, improving service quality and increasing the number of passengers served. The author has presented current studies on the field in optimization of public transport, mainly ways to optimize the transport network construction, based on large data sets about the population and their communication behaviour. Methods of combining various types of public transport with each other are presented. In the paper also are presents authors studies on the communication accessibility within the city of Cracow. Estimated distances from buildings to various types of public transport stops. The results were presented in aggregated form. Calculated communication speed of three types of public transport functioning in Cracow has also been discussed.
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Abstract

In the 1985 ablation season studies were made of the dynamics and size of the transport of suspended and dissolved material in a glaciated drainage basin (the Ebbaelva) and an unglaciated one (the Dynamiskbekken) in the central part of West Spitsbergen island. The dynamics of runoff, the exhaustion of sources of transportable suspended material, hysteretic effects during floods, the share of genetic type of water differing in the mineralisation level and chemical content, as well as the role of rain waters in mobilising soluble salts, are the principal factors of transport dynamics. The extremaly warm ablation season caused the extent of denudation to exceed the estimates made so far.
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Abstract

Traps to catch microfauna transported by wind were installed on already colonised by plants area, in the vicinity of the glacier. After 6-week-exposition 859 individuals of microfauna were caught, of which Nematoda constituted 71%, Tardigrada 22% and Rotifcra 7%. Number of microfauna individuals caught depended on distance from the already colonised areas and presence of plant parts, together with which animals can be transported more easily. Microfauna connected with vegetation, which is transferred together with plant parts, was transported in higher numbers. Probably these taxa (i.e. Diphascon within tardigrades and Dorylaimidae within nematodes) colonise new habitats at first, but other species dominate later in freshwater bodies.
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Abstract

Studies of the chemical composition of surface freshwaters of the Fugleberget drainage basin, Spitsbergen, were performed in the summer of 1979. It was found that activity of birds (little auk) is the main factor differentiating the chemical properties of waters of the drainage basin. The birds faeces cause the enrichment of waters with nutrients, fertilizing the environment. There is a dependence of the concentration of determined water chemistry parameters on the distance from the bird colony.
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Abstract

The aim of this work was to evaluate the use of the naphthalic anhydride safener on the protection of common bean cultivars BRS-Estilo (carioca) and BRS-Esplendor (black) from negative effects of herbicides. Two experiments were conducted, one for each cultivar in a complete randomized design with five replications, in a 6 × 3 factorial scheme, with six herbicide treatments: bentazon, fluazifop-P + fomesafen, bentazon + imazamox, fomesafen, cloransulam, and control without application, and three naphthalic anhydride treatments: without application, foliar application, and application via seed treatment. Visible injuries at 7, 14 and 21 days after application, photosystem II electron transport rate, and plant dry weight were evaluated. The naphthalic anhydride applied via foliar, and seed treatment reduced significantly the visible injuries in relation to the control when using the herbicides bentazon, fluazifop-P + fomesafen, bentazon + imazamox, and cloransulam. The photosystem II electron transport rate was protected by anhydride applied via foliar and seed treatment when using the herbicides bentazon, fluazifop-P + fomesafen and bentazon + + imazamox. The application of naphthalic anhydride via seed treatment protected the BRS-Estilo and BRS-Esplendor common bean cultivars, with no reductions in the plant dry weight when using the herbicides fluazifop-P + fomesafen, and fomesafen. The use of naphthalic anhydride via seed treatment and foliar application protected BRS-Estilo and BRSEsplendor common bean cultivars, from the negative effects of fluazifop-P + fomesafen and fomesafen herbicides. Thus, this practice has potential to be used in common beans.
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Abstract

The main goal of the considered work is to adjust mathematical modeling for mass transfer, to specific conditions resulting from presence of chemical surface reactions in the flow of the mixture consisting of helium and methanol. The thermocatalytic devices used for decomposition of organic compounds incorporate microchannels coupled at the ends and heated to 500 ◦C at the walls regions. The experiment data were compared with computational fluid dynamics results to calibrate the constants of the model’s user defined functions. These extensions allow to transform the calculations mechanisms and algorithms of commercial codes adapting them for the microflows cases and increased chemical reactions rate on the interphase between fluid and solid, specific for catalytic reactions. Results obtained on the way of numerical calculations have been calibrated and compared with the experimental data to receive satisfactory compliance. The model has been verified and the performance of the thermocatalytic reactor with microchannels under hydrogen production regime has been investigated.
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Abstract

Measurements of pollutants scavenged from air masses over southern Svalbard in summer precipitation are presented. Rainfall was sampled in July and August 2002 at Calypsobyen, Bellsund. Specific conductivity (SpC) and pH were measured and ion concentrations were determined by ion chromatography. Ions of marine origin were subtracted, assuming that all chlorides were of marine origin. The FLEXTRA trajectory model was applied to discover the sources of air masses arriving at Svalbard and track the paths of pollutant transport. Average (v/w) rainfall pH was 4.94, mean SpC amounted to 34.8 µS cm-1. Total dissolved solids concentration (TDS) ranged from 12.6 to 67 mg L-1, with ions of marine origin (Cl-, Na+, Mg2+) prevailing. Rains with the highest percentage of marine salts occurred with winds from the East at above average velocities. Non-sea salt (nss) sulphate concentrations ranged from 0.5 µeq L-1 to 23 µeq L-1, (v/w) average was 17 µeq L-1. Nitrate concentrations ranged from 0 to 24 µeq L-1. The highest concentrations of nss-SO42- and NO3- were measured on 25 August, when the highest rainfall occurred (27 mm) and pH was the lowest (4.65). Rainfall at Calypsobyen deposited 194 kg km-2 of acidifying anions and 263 kg km-2 of base cations over the recording period. The polluted air masses were mostly from northern and central Europe. Rainfalls scavenging air masses formed over Greenland and Norwegian Seas displayed similar concentrations, being probably polluted by SOx and NOx from ship emissions.
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Abstract

The development of air transport affects elements of the aviation fuel market. In recent years an increase in both the number of passengers and the number of passenger operations has been observed. This phenomenon also concerns passengers and the number of operations served by Polish airports which translates into more and more fuel consumption in Poland. The authors of the study tried to approximate the characteristics of aviation fuels used in various types of aircrafts. The most important of them, from the perspective of the Polish aviation sector, include Jet. This type of fuel plays a key role in civil aviation. In the article, the enterprises operating in the analyzed sector were also reviewed. The empirical part of the article is devoted, in turn, to the analysis of changes in air passenger transport in Poland and changes in Jet fuel prices on the Polish fuel markets. The conducted research shows that the dynamics of changes in the number of passengers, as well as the number of passenger operations at Polish airports were characterized by an upward trend, and the increase in the number of passengers was driven not only by a larger number of available flights, but also by such factors as: increasing the capacity of aircraft and increasing the fill rate for seats. The authors have also attempted to examine the strength of dependence between the number of passengers deciding to use Polish airports and Jet fuel prices, which in recent years have undergone significant fluctuations. For this purpose, the value of Pearson’s linear correlation coefficient was used and the analyzed period covered the years 2011–2017. The data on passenger traffic used in the study came mainly from periodic reports prepared by the Civil Aviation Office (ULC).
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Abstract

The paper presents differences between technical states and technical operation states of haul trucks in the technical operation process. The specification and analysis of operational parameters of technological vehicles used in surface mining is possible only due to more and more frequently used diagnostic – telemetric systems. While a detailed analysis of machines operation data can result in the more effective management of mining plant operations and the mining process itself. The determination of operational state indices and their individual components allows preventive actions to be commenced, resulting in improving the work organization of the entire mine machinery system. Moreover, the future technical state of machines operated in surface mining is strictly related to the current state and also depends on the events that occurred in the extraction system. A set of parameter values of individual state characteristics, which allow the haul trucks technical and operational state to be characterized, is a direct effect of a telemetric – diagnostic system operation.
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