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The transport of oversized loads, such as wind turbine components, represents a key logistical challenge due to specific technical and regulatory requirements. The development of the renewable energy sector, particularly wind energy in Poland, has significantly increased the demand for this type of transport. The implementation of wind farm construction projects requires not only advanced technological solutions but also special attention to transport safety and the organization of logistical processes. This study employed the FMEA (Failure Mode and Effects Analysis) risk analysis method, which allows for the identification of potential defects and their causes. Data were collected through surveys, interviews with representatives of transport companies, and field observations. The research sample included 11 companies specializing in oversized transport in Poland and European countries. Based on the gathered information, 15 typical risks associated with the transport of wind turbine components were identified. The most significant risks include the possibility of road accidents and discrepancies between the actual dimensions of the cargo and the transport documentation. The results highlight the need for improvements in route planning, precise verification of cargo parameters, and better management of administrative processes related to obtaining permits. The development of the wind energy sector and dynamic investments in wind farms make the optimization of oversized transport a crucial element in supporting the execution of eco-friendly projects and sustainable development. [ABSTRACT FROM AUTHOR]

The article examines the patterns of changes in transport costs of a company providing transport and logistics services. The transport company "M" was chosen as the object of the study. A table "Amount of transportation costs" was compiled, as well as diagrams "Share of transportation costs" and "Amount of transportation costs of the company" were compiled. Tariff rates and the possibility of changing them are analyzed. Based on the data obtained, it is concluded that the introduction of new tariff rates directly affects the transport costs of the enterprise. The purpose the study of the patterns of changes in transport costs of a company providing transport and logistics services on the example of the company "M". The change in the transport costs of a manufacturing enterprise is considered, taking into account changes in tariff rates, normalized depending on the length of the ride. Methodology: when conducting research, the authors used research methods such as analysis and synthesis. Results: as a result of the study, the following results were obtained: the transportation costs of the company "M" were calculated, the possibilities of changing tariff rates and the corresponding change in annual transportation costs were considered. The scope of the results: research activities to develop new approaches in the field of transportation and transport services.

Water injection for absorbing corrosive gases NH3, HCl and H2S is a widely employed method to mitigate the risk of ammonium salt corrosion in the hydrogenation units. To ensure the efficient prevention of ammonium salt corrosion, a numerical model integrating the hydrodynamics of gas–liquid and the reaction of interphase mass transfer was built based on Euler–Lagrange method in this work. The flow and mass transfer characteristics of complex multi-component system in water injection pipeline were investigated, and the correlation between process operating conditions and gas removal performance was analyzed. The results reveal that the removal efficiencies of corrosive gases in pipeline are influenced by the characteristics of gas–liquid flow and mass transfer, with HCl showing higher removal efficiency compared to NH3 and H2S. Furthermore, the increasing flow rate of water injection, the reducing corrosive medium content and the decreasing droplet diameter have a positive impact on the removal efficiencies of corrosive gases, while the impact of gas-flow velocity on the removal efficiencies of corrosive gases primarily depends on the residence time of droplets. These results have important theoretical value and engineering guiding significance for intensifying the process of water injection in hydrogenation units. [ABSTRACT FROM AUTHOR]

Water environment numerical models considering detailed hydrodynamic processes are effective tools to better understand the pollutant transport and transformation mechanisms and the influences of sediment and suspended sediment on pollutants in rivers in complex terrain. However, these models can hardly achieve simultaneous high-efficiency and high-accuracy simulation of large-area rivers in complex terrain. Therefore, a high-resolution water quality model was developed coupled with a sediment and suspended sediment module (GAST). The Compute Unified Device Architecture (CUDA) parallel computing architecture and robust model algorithms were used, and the model performance and functionality were improved. This model was based on detailed physical processes, while water environment parameter spatial heterogeneity also was considered. A simulation function of multiphase pollutant transport and mutual transformation was established by solving the pollution adsorption kinetic equation applicable to high-resolution terrain. The transport and mutual transformation processes of multiphase pollutants in still water and steady uniform flow were verified by considering the Nash–Sutcliffe efficiency (NSE) coefficient which exceeded 0.99. The validated high-resolution water quality model was applied to simulate a river network water environment in a sulfurous iron ore area, and the numerical results for the sulfate ion concentration spatial distribution and pollution sources of sulfate ions in the sediment and water phases were explored. The results show that the concentration of sulfate ions in the Xiaowenyu River varies between 120 and 180 mg/L. The contribution rates of the 5 tributaries with slag heaps in the lower reaches to the sulfate ion load in the Xiaowenyu River followed the order of Guojiagou (15.7%) > Baoquansi (14.6%) > Zhuyuangou (9.2%) > Qingshigou (2.8%) > Sunjiagou (1.4%). On an RTX30700d computer, only 0.55 h was needed to simulate the hydrodynamic and water quality evolution process involving 653,112 cells for a 6-h model setting. The model attained a high computational efficiency and high operation speed. This study provides a reliable tool for further study of river pollution mechanisms and river water environmental management. [Display omitted] • A high-resolution water environment numerical model with sediment and suspended sediment modul was developed. • The model can simulate water environment factors in 2D large river-network area with complex terrain at high resolution. • The sediment module and water environment parameter spatial heterogeneity was considered in the model. • The model enabled by GPU acceleration techniques illustrated high simulation efficiency and practical potential. [ABSTRACT FROM AUTHOR]

Silicon steel (electrical steel) has been used in electric motors that are important components in sustainable new energy Electrical Vehicles (EVs). The Ruhrstahl–Heraeus process is commonly used in the refining process of silicon steel. The refining effect inside the RH degasser is closely related to the flow and mixing of molten steel. In this study, a 260 t RH was used as the prototype, and the transport process of the passive scalar tracer (virtual tracer) and salt tracer (considering density effect) was studied using numerical simulation and water model research methods. The results indicate that the tracer transports from the up snorkel of the down snorkel to the bottom of the ladle, and then upwards from the bottom of the ladle to the top of the ladle. Density and gravity, respectively, play a promoting and hindering role in these two stages. In different areas of the ladle, density and gravity play a different degree of promotion and obstruction. Moreover, in different regions of the ladle, the different circulation strength leads to the different promotion degrees and obstruction degrees of the density. This results in the difference between the concentration growth rate of the salt tracer and the passive scalar in different regions of the ladle top. From the perspective of mixing time, density and gravity have no effect on the mixing time at the bottom of the ladle, and the difference between the passive scalar and NaCl solution tracer is within the range of 1–5%. For a larger dosage of tracer case, the difference range is reduced. However, at the top of the ladle, the average mixing time for the NaCl solution case is significantly longer than that of the passive scalar case, within the range of 3–14.7%. For a larger dosage of tracer case, the difference range is increased to 17.4–41.1%. It indicates that density and gravity delay the mixing of substances at the top area of the ladle, and this should be paid more attention when adding denser alloys in RH degasser. [ABSTRACT FROM AUTHOR]

In traffic flow, flyovers play a vital role in reducing traffic congestion, advancing commute timing, and helping to prevent collision scenarios. Inspired by the real-life applications of flyover, we model a coupled two-lane transport system where the lanes are divided into three segments in which the particle lane switching mechanism executes only in the middle segment of the lane, and particle inclusion and expulsion kinetics are performed in first and last segment of the lane to embody the infrastructure of flyover. The nature of the system characteristics is analyzed for diverse values of particle inclusion, expulsion, and coupling rates through graphical diagrams of phase planes, density profiles, shock dynamics, and phase transitions. The time-invariant behavior of the system is inspected numerically by utilizing the well-known method of mean-field theory, and it is discovered that the biased dynamics of particle inclusion, expulsion, and fully asymmetric coupling condition yield the phase diagram to disclose more unanticipated mixed stationary phases. Besides, the system experiences the fruitful novel incident of the double shock phase when the possibility of particle inclusion occurs relatively higher than the expulsion event. Also, it is noticed that the system experiences the fascinating phenomenon of shock propagation by traveling in either vertical/horizontal direction in the shock region of the phase diagram under the symmetric coupling circumstance, such as the position of the shock suddenly transits from the right to left segment without crossing the middle segment. The calculated numerical results are in good agreement with Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

Purpose: A key issue in the transportation of pallets is their proper preparation. The selection of an appropriate pallet, the stacking of goods and the proper securing of the pallet with the cargo is intended to minimize the risk of damage to the goods. Transporting goods on a pallet allows for additional protection of fragile items, as well as transporting heavy or oversized cargo. Unfortunately, damage to transport shipments is a common problem for many companies, for the sake of the damage to the goods being transported and the costs they entail. That's why it's so important to be safe when transporting pallet shipments to reduce its negative effects. This article addresses the problem of a logistics operator that serves its customers by first placing products on pallets and then loading the pallets onto trucks. In addition to the standard geometric constraints of keeping products from overlapping and exceeding the dimensions of pallets and trucks, there are many other constraints in this real-world problem, related to the total weight of the load or the distribution of the load inside the truck, as well as transportation safety. By analyzing the transportation process and shipment damage data, it was possible to propose measures to implement to reduce or eliminate the occurrence of damage to pallet shipments. Design/methodology/approach: The article briefly reviews the literature in the area of the concept of pallet. A map of the processes of execution of the transport order of pallet shipments was used, as well as FMEA analysis, which is an effective tool for identifying potential risks, causes of damage and their impact on the process of transporting pallet shipments. Findings: The purpose of the article was to analyze the current state of transportation management in the studied company using process mapping and to detect the causes of the appearance of damage to pallet shipments using FMEA analysis. Originality/value: As the selection of an appropriate pallet, the stacking of goods and the proper securing of the pallet with the cargo is aimed at minimizing the risk of damage to the goods, the topic addressed is relevant to the business of the logistics operator under review. [ABSTRACT FROM AUTHOR]

Background. The topic of evaluating the effectiveness of intelligent transport systems is relevant and important today. It exerts control effects on the transport system of the city (agglomeration) and ensures the achievement of the necessary level of indicators in terms of capacity, road safety, traffic congestion and traffic maintenance. Materials and methods. A generalized mathematical model of an intellectual transport system is formulated, containing the management process in a general form; The variants and methods of solving the problem of determining the effectiveness of the implementation of an intelligent transport system are presented. The description of the model of the management process and the intensity of operations has been expanded to allow considering the tasks of balancing transport systems, taking into account the functioning of information systems of motor transport. Results and conclusions. Thus, a mathematical model of the efficiency of intelligent transport systems has been formulated, which allows us to formulate and solve the problem of changing the distribution of elements of a transport system across subsets of states through the introduction of instrumental subsystems of intelligent transport systems.

In rivers, riverbeds are considered to have dual properties as a short-term sink and a source of further mobilization for microplastics. To better understand the sources, storage, and fate of microplastics in river systems, this study quantified the formation of microplastic hotspots in riverbeds and seasonal variations in microplastic inventories in riverbeds, especially for small-sized microplastics (

The value chain can be defined as a set of all processes and procedures necessary to deliver a product or service to the end-user through various stages of development. A concept of the value chain is essential in the context of transport, as the transport process is usually one of the last elements of the value chain and determines the final value of a product or service offered. In recent years, the domestic and international rail transport market has undergone significant changes, including ongoing globalisation processes, growing importance of international trade, increase in intermodal transport significance, numerous investment outlays in transport infrastructure, means of transport, and the area of rail transport interoperability. All the above-described aspects have an impact on the value chain in transport. This paper presents an analysis of the value chain in transport processes in an aspect of rail transport. Elements of the railway transport organisation process, which affect the entire value chain, were briefly characterised in this article. Moreover, based on statistical data and a literature review, factors that fundamentally impact the efficient organisation of rail transport processes were identified.

Copyright of Management & Quality / Zarządzanie i Jakość is the property of Scientific Society of Organization & Management / Towarzystwo Naukowe Organizacji i Kierownictwa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A significant part of the loss of live cargo (poultry) occurs in the process of its transportation by road to the processing plant. Currently, there are no studies of the factors that determine these losses, a mathematical model for optimizing the density of live cargo placement in a transport container, a method for managing delays at various stages of transportation, taking into account the structure of a modern poultry complex and the level of automation of its communication systems. In this regard, it can be argued that the purpose of this study, which is to increase the efficiency of transportation of live cargo by road by controlling the duration of transportation operations and optimizing the density of placement of live cargo in a transport container, is aimed at solving an urgent scientific and practical problem. Theoretical studies are carried out on the basis of the analysis of scientific and regulatory and technical literature, the legal framework, systemic, statistical, factorial and technical and economic analysis, mathematical modeling of the transport process. Experimental studies were carried out in the conditions of an operating enterprise using the methods of mathematical statistics, computer modeling, field observations. The main results that have scientific novelty are: the dependence of the losses of the transported cargo on delays in loading, moving and unloading the poultry carrier, taking into account the effective ambient temperature and the specific properties of the cargo; mathematical model for optimizing the density of placement of live cargo in a transport container; a method for managing delays at various stages of the transportation of live cargo by road. Further research is supposed to be carried out in the direction of the development of intellectual support for the management of transportation, both of live poultry within the boundaries of the enterprise, and of finished products.

The diversity and complexity of the parameters involved in the modeling of proton exchange membrane fuel cells (PEMFCs) have restricted further research and applications of such cells, and the similarity theory is a promising solution to this problem. The similarity theory is an effective tool to obtain compact and generalized results with the same precision as that of the basic mathematical model. This paper presents a comprehensive review of the application of the similarity theory to most aspects of PEMFCs. The advantages of using the similarity theory, such as generality, reduction in the test effort, convenient comparisons and guidance to scale up the experiment, are discussed and analyzed. Although a number of similarity criteria have been proposed in recent years, the similarity theory is not as widely applied or well accepted in PEMFC research as in the heat transfer and fluid flow domain. The objective of this paper is to demonstrate the feasibility of performing a similarity analysis for such complex systems and encourage researchers to present a dimensionless expression of their results in the follow-up PEMFC research. A key challenge is to use the similarity analysis for a complete gas-water-electricity-heat-mechanics coupled with PEMFC system and obtain the correlation between the dimensionless output voltage/current and input similarity criteria. This review indicates that none of the existing models can achieve this objective, and further research pertaining to this aspect must be performed. Several recommendations to achieve this aim, including a hierarchical classification of the criteria, are provided.

Objective: The objective of the article was to present the basic issues related to the functioning of transport processes in an enterprise, getting acquainted with and analysing selected areas of transport of the observed enterprise and showing how the practical use of information on the existing transport processes in the enterprise using selected methods and research tools allows for process optimisation. Design/methodology/approach: To determine the causes of the problem, it was decided to use quality management tools, i.e. the five whys analysis and fishbone diagram. In order to perform a detailed analysis, it was decided to use the SMED method to parameterise the implementation of the transport process. Findings: The analysis carried out before and after the introduction of the changes allowed to determine whether the problem was solved and what benefits the company gained. Examining the time of individual transport processes allowed to implement a new IT system, which contributed to the development of the company and allowed to save a large amount of capital. Originality/value: The results of the study can be used in strategic decisions of the company in the area of optimisation of transport processes. [ABSTRACT FROM AUTHOR]

To investigate the evolution of sediment provenances and transport processes in the central Bay of Bengal (BoB) since the Last Glacial Maximum, we present a comprehensive study on the grain size, clay minerals, rare earth elements, and accelerator mass spectrometry (AMS)14C analyses of the core BoB-24 sediments. Six AMS14C dates were obtained from planktonic foraminiferal Neogloboquedrina dutertrei (N. dutertrei) extracted from the core to reconstruct a reliable age model. The assemblage of clay minerals and the (La/Yb) UCC –δEu relationship indicated that the core contained a mixture of sediments from the Himalayas and Indian Peninsula. These results showed that the Himalayas were the main source of erosional materials during 25–6.5 ka BP, whereas those from the Indian Peninsula increased since the mid-Holocene. Between 25 ka BP and 12 ka BP, the sea level was relatively low, and a large amount of terrigenous detrital material were directly transported from the Himalayas and the Tibet Plateau to the study area by submarine canyons, forming a deposition center on the Bengal Fan. Between 12 ka BP and 6.5 ka BP, the sea level gradually rose and the Indian summer monsoon gradually strengthened, whereas the sedimentation rate and the amount of material transported from the Ganges–Brahmaputra River decreased greatly; the deposition center transferred from the Bengal Fan to the shelf of the BoB. Since 6.5 ka BP, the sea level has risen, reaching its present position. A high sea level and a strengthened East Indian Coastal Current resulted in an increase of material contribution from India, while the deposition center was on the shelf of the BoB. Overall, this study confirmed that both sea level fluctuations and variations of the Indian summer monsoon controlled the evolution of sediment provenances in the central BoB and transfer of the deposition center from the Bengal Fan to the continental shelf. This typical sedimentary pattern observed in the northeastern Indian Ocean improves our general understanding of past land–sea interactions. [Display omitted] [ABSTRACT FROM AUTHOR]

The value chain can be defined as a set of all processes and procedures necessary to deliver a product or service to the end-user through various stages of development. A concept of the value chain is essential in the context of transport, as the transport process is usually one of the last elements of the value chain and determines the final value of a product or service offered. In recent years, the domestic and international rail transport market has undergone significant changes, including ongoing globalisation processes, growing importance of international trade, increase in intermodal transport significance, numerous investment outlays in transport infrastructure, means of transport, and the area of rail transport interoperability. All the above-described aspects have an impact on the value chain in transport. This paper presents an analysis of the value chain in transport processes in an aspect of rail transport. Elements of the railway transport organisation process, which affect the entire value chain, were briefly characterised in this article. Moreover, based on statistical data and a literature review, factors that fundamentally impact the efficient organisation of rail transport processes were identified. [ABSTRACT FROM AUTHOR]

Japan Aerospace Exploration Agency (JAXA) plans a Phobos sample return mission (MMX: Martian Moons eXploration). In this study, we review the related works on the past climate of Mars, its evolution, and the present climate and weather to describe the scientific goals and strategies of the MMX mission regarding the evolution of the Martian surface environment. The MMX spacecraft will retrieve and return a sample of Phobos regolith back to Earth in 2029. Mars ejecta are expected to be accumulated on the surface of Phobos without being much shocked. Samples from Phobos probably contain all types of Martian rock from sedimentary to igneous covering all geological eras if ejecta from Mars could be accumulated on the Phobos surface. Therefore, the history of the surface environment of Mars can be restored by analyzing the returned samples. Remote sensing of the Martian atmosphere and monitoring ions escaping to space while the spacecraft is orbiting Mars in the equatorial orbit are also planned. The camera with multi-wavelength filters and the infrared spectrometer onboard the spacecraft can monitor rapid transport processes of water vapor, dust, ice clouds, and other species, which could not be traced by the previous satellites on the sun-synchronous polar orbit. Such time-resolved pictures of the atmospheric phenomena should be an important clue to understand both the processes of water exchange between the surface/underground reservoirs and the atmosphere and the drivers of efficient material transport to the upper atmosphere. The mass spectrometer with unprecedented mass resolution can observe ions escaping to space and monitor the atmospheric escape which has made the past Mars to evolve towards the cold and dry surface environment we know today. Together with the above two instruments, it can potentially reveal what kinds of atmospheric events can transport tracers (e.g., H2O) upward and enhance the atmospheric escape. [ABSTRACT FROM AUTHOR]

In palaeolimnology, microfossils play an important role as ecological indicators of lake history. A reliable interpretation of microfossil data requires a comprehensive understanding of transport processes as well as determining whether microfossil assemblages are representative of their living communities. The occurrence of transport in ostracod taphocoenoses can be identified from the population age structure of valves. In this study, 23 surface sediment samples from Dalongchi Lake, northwestern China, were analysed for species composition, and 16 were also analysed for the population age structure of Fabaeformiscandona gyirongensis. Ostracod valves are dominated by F. gyirongensis, with frequently occurring Ilyocypris sp. in the surface sediments. The distribution and abundance of ostracods are significantly correlated with the sampling depth and grain size, implying that hydrological conditions are the major controlling factor. The dominant species F. gyirongensis seems to prefer relatively deep and stable lacustrine conditions, while Ilyocypris sp. seems to prefer shallow conditions with rich submerged macrophytes and relatively coarse substrate in Dalongchi Lake. The spatial changes in the population age structure of F. gyirongensis match the different hydrodynamic regimes within the lake, with abundant early and middle instars in deeper waters and abundant middle and late instars in shallower waters, denoting that downslope transport of valves may be responsible for the spatial changes in the population structure. Our findings, together with previous works, indicate that downslope transport of instars and subsequent depth differentiation of the population structure of ostracods can occur for different species in both marine and lacustrine settings, which potentially leads to some biases based on the “in situ” inference of microfossils in palaeoenvironmental reconstruction. Hence, careful transport process assessment of fossil assemblages based on population age structure and other characteristics, such as the ratios of adults to juveniles and carapaces to valves, is a valuable prerequisite for palaeoenvironmental analysis.

This study mainly focuses on the transport process of broken rocks in geological fractures, faults, and karst conduits. Because previous research mainly focused on the influencing factors of adverse geological conditions, there is no clear understanding of the migration behavior of fillings and the formation process of pathways in the process of water inrush. An experimental testing apparatus was designed and developed to perform systematic research on the transport process of granular soils subjected to seepage flow. This system was comprised of a water supply system, acrylic glass holding device, and collection system, which could effectively be used to study the influence of discontinuous gradation and flow velocity on the permeability characteristics of loosening fillings. The experimental results show that the water inrush induced by seepage failure results from the gradual migration and loss of particles by water seepage. According to the fine-grain content and loss characteristics of the samples, the samples are divided into three types: those with a nonskeleton structure, with a dense-suspension structure, and with a void-skeleton structure. With an increase in the content of fine particles, the porosity and permeability decrease whereas the time required for water inrush of the sample gradually increases. With an increase in flow velocity, the time required for water inrush and its rate of change gradually decrease. However, the mass loss of particles does not increase with the increasing flow velocity during the same period. The research results provide a valuable reference with which to further study the mechanism of variable mass seepage in faulted and fractured rock. [ABSTRACT FROM AUTHOR]

Improving gas-liquid mass transfer efficiency in aeration systems contributes to energy savings, cost reduction, and enhanced efficiency in wastewater treatment. However, due to the complex nonlinear interactions among bubbles in turbulence, understanding the transport mechanisms of non-uniform bubble clusters in turbulence remains unclear. This study employs a combined approach of experimental research and numerical simulations to investigate the shape, diameter distribution, trajectory, and velocity of bubbles under different aeration port sizes and flow rates. The diameter distribution of bubble clusters exhibits a bimodal distribution. Bubble trajectories during ascent mainly exhibit two types of motion patterns: "Z" shaped and linear. Increasing aeration port size and flow rate both lead to an increase in the maximum bubble diameter. Higher initial flow rates and smaller port sizes induce greater lateral velocity fluctuations in bubbles. The proposed numerical simulation method serves as a reference for simulating the transport of non-uniform bubble clusters. • Complex forces cause diameter fluctuations in bubble clusters during transport. • Higher aeration rates or larger ports expand bubbles and increase their diameter. • Bubble diameter distribution widens with increasing flow velocity or port size. • Bubbles ascend in "Z" or linear paths, influenced by shape and initial conditions. [ABSTRACT FROM AUTHOR]

Transport is one of the key elements allowing to achieve goals, tasks and plans. Transport need results from the necessity of moving from one place to another. To make it happen, the resource in the form of a means of transport is necessary. Another aspect is organizational actions. The basic source of transport demand is diversity of distribution of the factors allowing to run business. Due to globalization of economy, range and frequency of transports have considerably increased. New logistic chains, networks of terminals and intermodal connections are being created every year. The goal of all these actions is to reduce transport costs and improve the whole process. The authors of this article set a goal of defining the role of optimization of transport costs using a consolidation service. Conducted analysis confirmed that consolidation services reduce the costs of transport of small cargos.

Previous studies have shown that the ionospheric responses to a solar flare are significantly dependent on the solar zenith angle (SZA): the ionospheric responses are negatively related to the SZAs. The largest enhancement in electron density always occurs around the subsolar point. However, from 2001 to 2014, the global distribution of total electron content (TEC) responses showed no obvious relationship between the increases in TEC and the SZA during some solar flares. During these solar flares, the greatest enhancements in TEC did not appear around the subsolar point, but rather far away from the subsolar point. The distribution of TEC enhancements showed larger TEC enhancements along the same latitude. The distribution of anomalous ionospheric responses to the solar flares was not structured the same as traveling ionospheric disturbances. This anomaly distribution was also unrelated to the distribution of background neutral density. It could not be explained by changes in the photochemical process induced by the solar flares. Thus, the transport process could be one of the main reasons for the anomaly distribution of ionospheric responses to the solar flares. This anomaly distribution also suggests that not only the photochemical process but also the transport process could significantly affect the variation in ionospheric electron density during some solar flares.

In physics, chemistry, and mathematics, the process of Brownian motion is often identified with the Wiener process that has infinitesimal increments. Recently, many models of Brownian motion with finite velocity have been intensively studied. We consider one of such models, namely, a generalization of the Goldstein–Kac process to the three-dimensional case with the Erlang-2 and Maxwell–Boltzmann distributions of velocities alternations. Despite the importance of having a three-dimensional isotropic random model for the motion of Brownian particles, numerous research efforts did not lead to an expression for the probability of the distribution of the particle position, the motion of which is described by the threedimensional telegraph process. The case where a particle carries out its movement along the directions determined by the vertices of a regular n + 1-hedron in the n-dimensional space was studied in [13], and closed-form results for the distribution of the particle position were obtained. Here, we obtain expressions for the distribution function of the norm of the vector that defines particle's position at renewal instants in semi-Markov cases of the Erlang-2 and Maxwell–Boltzmann distributions and study its properties. By knowing this distribution, we can determine the distribution of particle positions, since the motion of a particle is isotropic, i.e., the direction of its movement is uniformly distributed on the unit sphere in ℝ3. Our results may be useful in studying the properties of an ideal gas. [ABSTRACT FROM AUTHOR]

Copyright of Zeszyty Naukowe SGGW: Ekonomika i Organizacja Logistyki is the property of Warsaw University of Life Sciences (SGGW), Faculty of Economic Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Low liquid-loading flow frequently occurs during the transport of gas products in various industries, such as in the Oil & Gas, the Food, and the Pharmaceutical Industries. Even small amounts of liquid can have a significant effect on the flow conditions inside the pipeline, such as increased pressure loss, pipe wall stresses and corrosion, and liquid holdup along the pipeline. However, most studies that analyze this type of flow only use atmospheric pressures and horizontal 1-in or 2-in pipes, which do not accurately represent the range of operating conditions present in industrial applications. Therefore, this study focused on modeling low liquid-loading flow in medium-sized (6–10 in) pipes, using CFD simulations and experimental data from the University of Tulsa, and then applying it to real operating conditions from a Colombian gas pipeline. An acceptable difference was observed between experimental and CFD data, both for the liquid holdup (18%) and for the pressure drop (12%). Variables like pressure drop and wall shear stress increase with phase velocity, operating pressure, and pipe inclination. Liquid holdup increases with liquid velocity but decreases with all other factors. The relation of flow variables with phase velocities is of particular interest: Doubling the gas velocity decreased holdup 70% and increased pressure drop tenfold. On the other hand, the presence of the liquid phase seems to be more influential on process variables than its exact flowrate; the introduction of the liquid phase to a single-phase gas causes an increase in pressure loss by a factor of three, but doubling the liquid velocity only increases the pressure loss by a further 30%.

Solidifiers are dry, granular hydrophobic polymers that form physical bonds with hydrocarbons by molecular interactions (hydrogen bonding, London forces), and are used to immobilize hydrocarbon spill propagation and dispersion. CIAgent© is a non-toxic, proprietary polymer blend listed as an “Oil Solidifier” on the EPA's National Contingency Plan Product Schedule for use on hydrocarbon spills in the navigable waterways of United States. CIAgent solidifies the liquid hydrocarbons through a rapid transformation into a cohesive rubber-like inert mass upon contact and retains the liquid for easier removal and disposal. The objective of this paper is to determine the effectiveness of the solidifier with a variety of hydrocarbon liquids that could be encountered in an oil spill scenario. The effectiveness of the solidifier was characterized in terms of the application rate, temperature change, solubility parameters and solidification time for a variety of hydrocarbon liquids (e. g., gasoline, diesel fuel, crude oil) that could be encountered by measuring the heat of solidification using a solution calorimeter. A thermogram was obtained and the heat of solidification was calculated using the temperature difference upon solidification. The temperature change and the degree of swelling in the solidifier were used to determine the solubility parameter of the solidifier (6.77 Hildebrands). The heat of solidification value was used to determine the ease and speed of the solidification of the hydrocarbon liquids. Solidification times ranged from 40 to 120 s for the liquids tested. The average application ratio in weight of solidifier to weight of hydrocarbon ranged was 3.35.

Biomass has been considered a potential source of value-added products and energy vectors. Most biomass studies have researched the best pathways or processes to upgrade this renewable raw material through stand-alone processes or biorefineries. The biomass supply chain is a crucial aspect in the economic analysis of biomass upgrading since most of the raw materials need to be transported. A supply chain analysis gives an idea about the availability, real costs, and storage conditions of the raw material to guarantee an accurate feasibility analysis and a standardized production process. Calendula (Calendula Officinalis) is an aromatic plant used to produce valuable extracts in the cosmetic and pharmaceutical industries. Nevertheless, high amounts of exhausted biomass (more than 95% w/w) are produced and wasted. Theseresidues represent an environmental issue to be solved through the implementation of valorizing options. This paper analyses the supply chain and environmental impact of essential oil production using Calendula (Calendula Officinalis) as a raw material in the Colombian context. The case study comprises a single-objective optimization of the calendula supply chain to produce essential oil and the life cycle assessment (LCA) of the process through a cradle-to-gate approach in the Colombian context. The results showed the best locations to upgrade Calendula in Colombia (i.e., Manizales and Bucaramanga), supplying 1.1 % of the total product demand. The optimal product flow to customers was 0.32 tons/year, and the required feedstock from suppliers was 162 tons/year. The agricultural stage of essential oil production represented the highest environmental impact of the supply chain. In particular, plastic sheets, organic fertilizers, and chemical fungicides were the main contributors to this impact.

A two-level full factorial design was used to analyze several factors involved in PSF–GO–Pebax thin film nanocomposite membranes development. Permeate flux was chosen as a single response for four possible factors: Pebax selective layer concentration, amount of GO load to Pebax selective layer, Pebax–GO selective layer thickness, and amount of GO load to PSF substrate. The study is aimed at factors interaction and contribution towards the highest permeation flux via FFD and RSM approach. R2 obtained from the ANOVA is 0.9937 with Pebax concentration as the highest contributing factor. Pebax concentration–amount of GO load to PSF substrate is the only interaction contributing to the highest flux. A regression analysis concluded the study with model development and an optimized condition for the membrane design.

Air pollution due to haphazard industrialization has become a major concern in developing countries. Yet, enforcement of related norms remains problematic because violators cannot easily be pinpointed among closely situated industrial units. Accordingly, it has become imperative to equip regulatory authorities with an economical yet accurate tool that quickly locates emission sources and estimates emission rates. Against this backdrop, we propose RESILIENT, a method for Robust Estimation of Source Information from LImited field measuremENTs, which exhibits significant statistical robustness and accuracy even when the data are collected using a low-cost error-prone sensor. In our field experiment, where ground truth was unavailable, the sources estimated to be inactive based on the complete set of measurements were found inactive (up to three decimal places of accuracy) at least 72% of the time even when estimated using just 54% of random measurements. In that setting, rate estimates of active sources were also found to be statistically robust. For direct validation of RESILIENT, we considered a separate public dataset involving 10 tracer experiments, and obtained a significant correlation coefficient of 0.89 between estimated and recorded emission rates, and that of 0.99 between predicted and measured concentration levels at sensor locations.

The evaluation of a new air water generator (AWG) based on absorption and reverse osmosis is described. For the evaluation, an aqueous lithium bromide solution has been selected from a wide range of liquids as the absorbent. At high salt mass fractions, the aqueous lithium bromide solution has a low vapour pressure and a high osmotic pressure. The low vapour pressure ensures that the water vapour can be absorbed from the air, but the high osmotic pressure leads to high pressures over the membrane. Due to the high osmotic pressures, several reverse osmosis membrane modules are necessary and salt solution has to be present on both sides of the membrane, which leads to an additional inlet on the permeate side. Models for the absorber, the reverse osmosis membrane module and the complete multi-stage reverse osmosis system have been developed in Python. The model of the complete system has then been used to simulate the performance of the AWG at different boundary conditions. The simulations have shown that based on the defined assumptions, extracting water from the air with absorption and reverse osmosis is possible and that the energy demand per litre of pure water is similar to AWG systems which use condensation.

A new phenomenological model, based on a second order dissolution kinetics, was developed for the alkaline removal of non-collagenous protein (NCP) from the skin of Nile tilapia (SNT). This model allows estimating the liquid concentration of NCP in terms of temperature, skin size, NaOH concentration and time. This model was fitted with 135 experiments averaging a R2 of 0.99. The root-mean-square deviation and the mean-absolute-percentage error of the model were 0.0041 and 3.15%, respectively. The Arrhenius-activation energy was 15–122 kJ mol−1. Multi-objective optimization led to the highest NCP extraction (NCPE) of 24.3% and to the lowest loss of collagen (LC) of 1.3%, with R2 coefficients of 0.98 and 0.92, respectively. Ultimately, SNT deproteinized under optimal conditions was subjected to acid extraction and purification. FTIR and SEM analyses indicated that the product was a Type I collagen that could be used in the pharmaceutical industry.

Introduction. The article determines the relevance of the scientifically sound solutions and effective tools’ development in the evaluation of the passenger companies’ performance. The author notes that these decisions should be based on the modern methodological principles for assessing the complexsystems’ performance, taking into account the specific of the transport service process and the general requirements for evaluation methods. Materials and methods. The methods and tools of the quality management system, methods of system and the methods of structural and comparative analysis are used in the research. The main approaches to the task assessing effectiveness of the complex systems’ functioning are singled out, and their shortcomings, and the possibility of their application for the evaluation of performance in the theory of passenger motor transport are determined. Results. The author proposes to use the index normalization method to develop a methodology for assessing the performance of passenger enterprises, where the whole set of carefully selected indicators in accordance with accepted standards is converted from absolute values to relative ones. In accordance with it, the tasks and stages of subsequent research are defined. The article presents the classification model of the basic system formation of performance indicators and the functional scheme of their grouping for the subsequent indicators’ ranking by significance within each of the four groups. Discussion and conclusion. The author concludes that the index rationing method could be used for urban public transportation terms. Systematized enterprises’ indicators should be ranked in order of importance, first of all for the passenger, then for the department of transport, and only then for the enterprise, because efficiency in market conditions is not only a good financial result, but also the enterprise competitiveness for the quality of services and the amount of subsidies.

Introduction/background: The article presents an analysis of risk factors that may cause disruptions affecting the shipping of parts and components for the automotive industry. In this regard, based on literature research, the meaning of a disruption risk and its management in transport processes are discussed. Furthermore, the role of the transport and logistics companies in the provision of services for the automotive sector is presented. In the next section, the methodology of risk factor analysis and assessment is determined and the results of studies conducted on disruptions that may have a key impact on the transport process of the analysed company are presented. Aim of the paper: The aim of the article is to determine the influence of disruptions in the transport processes of parts and components for the automotive industry through the analysis and assessment of disruption risk factors. Materials and methods: The tools and methods proposed to assess the risk of disruptions affecting the order execution for the transport service of parts and components for the automotive industry by the company under examination were as follows: an indicative analysis, a disruption risk assessment form, an expert judges method, PHA method and a risk matrix. Results and conclusions: The analysis has allowed for the identification of risk factors, which, due to the potential consequences estimated by a group of experts as well as the probability of occurrence, may have a key impact on the transport process in the investigated company. Indicative analysis has shown that the timeliness of transport, which is associated with delivery time, is a major issue in a company. This formed the basis for the further analysis of process disruptions. [ABSTRACT FROM AUTHOR]

Observations have revealed widespread emissions of alkyl nitrates from the tropical and Southern Oceans. We present the first chemical transport model simulations to examine the global impact of these emissions. Matching observed atmospheric abundances, we derive a total oceanic flux of methyl nitrate (MeONO2) and ethyl nitrate (EtONO2) equivalent to 0.35 Tg of N per year, which contributes as much as 1 DU to the tropospheric ozone column in the Western Pacific and is responsible for about 3% of the global oxidative capacity of the troposphere.

Seasonal and interannual variability in atmospheric carbon dioxide (CO2) concentrations was simulated using fluxes from fossil fuel, ocean and terrestrial biogeochemical models, and a tracer transport model with time-varying winds. The atmospheric CO2 variability resulting from these surface fluxes was compared to observations from 89 GLOBALVIEW monitoring stations. At northern hemisphere stations, the model simulations captured most of the observed seasonal cycle in atmospheric CO2, with the land tracer accounting for the majority of the signal. The ocean tracer was 3–6 months out of phase with the observed cycle at these stations and had a seasonal amplitude only ∼10% on average of observed. Model and observed interannual CO2 growth anomalies were only moderately well correlated in the northern hemisphere (R ∼ 0.4–0.8), and more poorly correlated in the southern hemisphere (R < 0.6). Land dominated the interannual variability (IAV) in the northern hemisphere, and biomass burning in particular accounted for much of the strong positive CO2 growth anomaly observed during the 1997–1998 El Niño event. The signals in atmospheric CO2 from the terrestrial biosphere extended throughout the southern hemisphere, but oceanic fluxes also exerted a strong influence there, accounting for roughly half of the IAV at many extratropical stations. However, the modeled ocean tracer was generally uncorrelated with observations in either hemisphere from 1979–2004, except during the weak El Niño/post-Pinatubo period of the early 1990s. During that time, model results suggested that the ocean may have accounted for 20–25% of the observed slowdown in the atmospheric CO2 growth rate

Inverse estimation of carbon dioxide (CO2) sources and sinks uses atmospheric CO2 observations, mostly made near the Earth's surface. However, transport models used in such studies lack perfect representation of atmospheric dynamics and thus often fail to produce unbiased forward simulations. The error is generally larger for observations over the land than those over the remote/marine locations. The range of this error is estimated by using multiple transport models (16 are used here). We have estimated the remaining differences in CO2 fluxes due to the use of ocean-only versus all-sites (i.e., over ocean and land) observations of CO2 in a time-independent inverse modeling framework. The fluxes estimated using the ocean-only networks are more robust compared to those obtained using all-sites networks. This makes the global, hemispheric, and regional flux determination less dependent on the selection of transport model and observation network.