bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficiency of the UN action in the area of transport, environmental protection, health
Authors: Ermolina Marina , Matveevskaya Anna , Pogodin Sergey
Published: November 2018

The paper examines the performance of the UN Economic Commission for Europe (UNECE) in the field of transport, environment and health. In the course of the study, the tasks of reviewing and summarizing the main arguments of supporters and critics of UN activities in this field and forecasting the development of its potential in the future, the institutional features of the reforms to achieve sustainable development, as well as the most important problems of the green economy are performed. The authors emphasize that in the recent 25 years environment protection has become a priority for the UN activity. Additionally, international conferences on environmental issues and sustainable development have been an important tool to define global priorities, to raise awareness about these issues and to draw attention to essential problems that can be neglected. According to the authors of this study, no matter how inspiring the tendency of the growth of the number of specialized agencies involved in solving problems of transport, environment and health, these efforts are clearly not enough. The paper substantiates the conclusion that today the UN is the only global organization with the required resources to be able to positively influence the sphere of environmental protection. At the same time, comprehensive institutional mechanisms to improve the transport system, environmental protection and the coordination of health strategy are needed within the framework of the activities of the specialized UN agencies.
Research of interaction of the “train – bridge” system with bridge deck resonant vibrations
Authors: Diachenko Leonid , Benin Andrey , Diachenko Anastasiia
Published: November 2018

When designing bridges on high-speed railways, special attention should be paid to ensuring the safety of train traffic and the comfort of passengers. On high-speed railways, the proportion of the length of bridge structures in the composition of the entire route is much larger than on conventional railways, which makes the present study relevant. In this paper based on numerical simulation, the results of the study of the motion of a high-speed train along bridge structures in the resonance mode of vibrations are presented. In this formulation, special attention was paid to the control of dynamic phenomena at the level of the “wheel-rail” contact. The dynamics of loose parts of the train car determines the magnitude of the contact force, which in turn characterizes the possible detachable movement of the wheel, which is inadmissible for the safety of the train. Analysis of the obtained results, using the example of a 50 m long simple span structure developed for the Moscow-Kazan high-speed railway, allows us to conclude that the resonant nature of the vibrations of simple beam is not a critical phenomenon.
Results of modeling the behavior of the subgrade with pressure injection of solidifying solutions
Authors: Lanis Aleksey
Published: November 2018

Further development of railway transport is possible through increasing the traffic intensity by increasing the weight and number of trains and their speed. The growth of defects and deformations of the subgrade is inevitable, and the issues related to the reinforcement of soils of the subgrade are relevant. Measures that result in reliable operation of railway infrastructure facilities can be implemented during major repairs or new construction, which requires traffic restriction and leads to additional economic costs. Thus, one of the priority issues is the development and implementation of ways to reinforce the subgrade of railways without traffic restriction. Such methods can include pressure injection, as well as various modifications of this method based on combining known methods of reinforcement and injection.
The application of the principles of the theory of shakedown to the calculation of pavement layers of granular materials in shear
Authors: Aleksandrov Anatoly , Dolgih Gennadiy , Ignatov Vitaly , Kalinin Aleksander
Published: November 2018

In the report ways of application of the theory of shakedown of material to calculation of coverings and the bases of pavements from the granulated materials are considered. The basic limits of shakedown are given, which include the limits of resilient, elastic and plastic shakedown. The results of three-axis tests are given, on the basis of which the character of accumulation of residual deformation is divided into damped, steady and progressive. These data allow to predict the nature of deformation and provide damped deformation of the granular material, limiting the stress at the most dangerous point.
The study of the correspondence of marketing instruments to the stages of the start-up life cycle
Authors: Nikiforova Svetlana
Published: November 2018

The article is devoted to the results of an empirical study of the correspondence of market research methods and promotion tools to the stages of the life cycle of start-ups on the Russian market. The authors’ model of the life cycle of the start-up, consisting of eight stages, is grounded. The authors present the results of an empirical study, consisting of expert interviews and a quantitative survey. A model for the correspondence of marketing instruments to the stages of the life cycle of a start-up is compiled. It is proved that in the process of development of a start-up, the number of marketing instruments used (especially digital tools) should increase at every stage of its life cycle. Based on the results of a desk and empirical studies, a system of criteria and a tool for assessing the sustainable development of a startup at various stages of its life cycle are proposed.
Economics of transport and sustainable development: problems of high education in Russia
Authors: Kankovskaya Alina , Kalinina Olga , Ilin Igor
Published: November 2018

Transport is one of the most important spheres in the sustainable development of countries and regions. Therefore, the article analyses the extension of the concept of sustainable development in Russian higher education in transport engineering and economics. We analysed the higher education standards and educational programs of universities, identified problems in the implementation of the concept of sustainable development in Russian higher education in the field of transport engineering and suggested ways to address them.
Economic assessment of the control of human-factor impact on faults of technical facilities in railway-transport technological processes
Authors: Vorobyov Valery , Manakov Aleksey , Repina Irina
Published: November 2018

In the present paper, we substantiate the necessity of control and economic assessment of the human-factor (HF) impact on faults of technical facilities in railway-transport technological processes. An algorithm for calculating the economy due to the reduction of losses caused by railway-infrastructure faults is proposed; this algorithm is based on the calculation of the losses versus the quantity and duration of the related faults.
Evaluation of the investment process in the region and the influence of social well-being of the population on it
Authors: Gratsinskaya Galina , Levizov Vladislav , Kovalev Vladislav
Published: November 2018

The authors of the present paper consider the main indicators for assessing the investment process in the region. The influence of effective human capital on this process is substantiated. The paper shows that the formation of such human capital in modern Russia depends on the social well-being of the population of the region, which in its turn is largely determined by the existing level of social justice. The Lorentz curves, the Gini coefficient and the Robin Hood index are proposed to be used for objective assessment of this level. In order to create more favorable conditions for the formation of effective human capital in the region, it is proposed to use progressive taxation and state social transfer payments, create and develop institutions of civil society, increase the investment activity of private business, the state and public-private partnership.
Numerical modeling of heat transfer in the fixed-matrix regenerator working in the Electric Thermal Storage heating system
Authors: Cisek Piotr , Taler Dawid , Cisek Grzegorz
Published: November 2018

The study presents the concept of Electric Thermal Storage (ETS) central heating system. Thermal Energy Storage (TES) is carried out in the fixed-matrix regenerator. The energy conservation equations, determined for the discharge period of the regenerator operation, are implemented in MATLAB numerical procedures based on the Finite Volume Method (FVM). In the model pressure drops within the system are calculated, both for the airflow through the inner tubes, and between the tubes. The flow distribution calculations show that the assumption of even air flow distribution would not be justified. Subsequently, the values of heat transfer coefficients are determined for the four distinct heat transfer surfaces, for the variable axial coordinate z and during the time of the system operation. The use of two different criterion equations is considered, for determining the mean Nusselt number Num for fluid flow through the concentric annular duct, as well as for the local Nusselt number Nuz calculated for the fluid flow through a circular or non-circular ducts. The most appropriate approach is selected by comparing the calculation results with experimental data. Taking into account the relative error, RMSE, and MAPE values calculated, it may be concluded that the Taler correlation – for non-circular ducts – gives results closer to the experimental data obtained.
An inverse geometric problem in steady state heat conduction – the solution and stability analysis
Authors: Hożejowski Leszek
Published: November 2018

The paper addresses a numerical method for boundary identification in a problem governed by Laplace’s equation. The proposed numerical procedure for discrete reconstruction of the unknown boundary from the given temperature data is based on the Trefftz method. In contrast to the procedures described in the reference papers, the present approach requires significantly less and easier computation. The paper undertakes analysis of the resistance of the solution to small perturbations of the prescribed temperature condition at the unknown part of the boundary. We define and then estimate a sensitivity factor which allows quantitative assessment of the relationship between temperature measurement errors and boundary identification errors, even if the exact solution is not known. The included numerical examples demonstrate the effectiveness of the proposed method for boundary reconstruction and present the analysis of numerical stability using a sensitivity factor.
Modelling microwave heating of an oil palm mesocarp
Authors: Law Ming , Chang Jessie
Published: November 2018

An oil palm mill often uses steam in sterilization and fruit detachment processes. Consequently, a large amount of wastewater is produced. To reduce the wastewater, microwave (MW) heating of oil palm fruits has been studied and positive results were reported in open literature. Nevertheless, MW heating of oil palm fruits requires proper control to avoid overheating, which deteriorates the oil quality. MW heating efficiency depends not only on the electromagnetic strength, but also on the complex permittivity of oil palm fruits. This study reports the MW heating model of an oil palm mesocarp. The three-dimensional model solved Maxwell’s Electromagnetic waves equation, diffusion equation of moisture content, and heat conduction equation. The model was validated with mesocarp’s experimental data of moisture content and temperatures. The electromagnetics, moisture, and temperature distributions of the mesocarp were studied. The simulation results showed that the volumeand surface-averaged temperature were similar, thus the surface temperature might be used as a good approximation to the volumetric temperature. Besides, the model also showed that radiation and convection were the main heat loss mechanisms. This validated model can be used for designing a microwave heating reactor for oil palm fruits.
Numerical study of the effect of heat transfer on solid phase formation during decompression of CO2 in pipelines
Authors: Martynov Sergey , Zheng Wentian , Mahgerefteh Haroun
Published: November 2018

CO2 solid phase formation accompanying rapid decompression of high-pressure CO2 pipelines may lead to blockage of the flow and safety valves, presenting significant hazard for safe operation of the high-pressure CO2 storage and transportation facilities. In this study, a homogeneous equilibrium flow model, accounting for conjugate heat transfer between the flow and the pipe wall, is applied to study the CO2 solid formation in a 50 mm internal diameter and 37 m long pipe for various initial thermodynamic states of CO2 fluid and wide range of discharge orifice diameters. The results show that the rate of CO2 solid formation in the pipe is limited by heat transfer at the pipe wall. The predicted amounts of solid CO2 are discussed in the context of venting of CO2 pipelines.
The flow boiling heat transfer coefficient determination in a minichannel used the FEM combined with Trefftz functions
Authors: Piasecka Magdalena , Strąk Kinga , Maciejewska Beata
Published: November 2018

The method of solving the inverse heat conduction problem, by means of the FEM with Trefftz-type basis functions, during flow boiling in a minichannel was shown. This basis functions were constructed with using the Hermite interpolation and Trefftz functions. The aim of the numerical calculations was to determine the local heat transfer coefficient on the basis of experimental data in a horizontally oriented minichannel. The refrigerant flowing along the minichannel (HFE-649 or HFE-7100) was heated by a thin enhanced plate by vibration-assisted laser texturing. The temperature on an outer smooth side of the plate was detected by means of infrared thermography. On the heated wall–fluid contact surface in the minichannel the heat transfer coefficient was obtained from the Robin boundary condition. It was assumed that the temperature distribution in the heated plate was described by the Poisson equation. The unknown values of temperature and temperature derivatives at nodes were computed by minimizing the functional which describes the mean square error of the approximate solution on the boundary and along common edges of neighbouring elements. The results were presented as the heated plate temperature and heat transfer coefficient versus the minichannel length.
Review of existing and development of a novel mathematical model for supercritical CO2 cycles working fluid
Authors: Wołowicz Marcin , Milewski Jarosław , Lis Piotr
Published: November 2018

The paper aims to compare the models of working fluids against experimental data for carbon dioxide close to its critical conditions. Fortunately, most of the work is already done and published where the authors compared the models based on the equation of the state (EoS). There are a few other models which were not investigated, thus we would like to add a few new results here and focus only on near-critical properties where the biggest deviation between experimental and calculated properties can be observed. The area of interest was pressure range of 7.39 – 20 MPa and temperature range of 304-340 K just above fluid critical point (7.39 MPa, 304.25 K). Model validation was performed for density and heat capacity as one of the most important parameters in preliminary cycle analysis.
Experimental investigation on straight and u-bend double tube heat exchanger with active and passive enhancement methods
Authors: Andrzejczyk Rafal , Muszynski Tomasz , Kozak Przemysław
Published: November 2018

Authors in this work want to demonstrate the possibility to increase the heat transfer efficiency by using simple wire coil inserts to create turbulent flow in the boundary layer as well as air blowing into the annulus of the pipe. In the study, Wilson plot approach was applied in order to estimate heat transfer coefficients for all heat exchanger (HX) configurations. The study focuses on experimental values of heat transfer coefficient (HTC) and pressure drops. The primary objectives of the work are to: I. Provide an experimental comprehensive database for HTC and pressure drops; II. Analysis effect of different flow conditions e.g. water mass flow rate, the void fraction on heat transfer and hydraulic performance of tested elements. III. Compare influences of both passive and active methods at the efficiency of simple heat exchangers constructions; IV. Validation experimental results with selected experimental models from the open literature.
Experimental studies and numerical modelling of heat and mass transfer process in shell-and-tube heat exchangers with compact arrangements of tube bundles
Authors: Gorobets Valery , Bohdan Yurii , Trokhaniak Viktor , Antypov Ievgen
Published: November 2018

Shall-and-tube heat exchangers based on the bundles with in-line or staggered arrangements have been widely used in industry and power engineering. A large number of theoretical and experimental works are devoted to study of hydrodynamic and heat transfer processes in such bundles. In that, works the basic studies of heat and mass transfer for these bundles are found. However, heat exchangers of this type can have big dimensions and mass. One of the ways to improve the weight and dimensions of the shell-and-tube heat exchangers is to use compact arrangement of tube bundles. A new design of heat exchanger is proposed, in which there are no gaps between adjacent tubes that touch each other. Different geometry of these tube bundles with displacement of adjacent tubes in the direction of transverse to the flow is considered. Numerical modelling and experimental investigations of hydrodynamic, heat and mass transfer processes in such tube bundles has been carried out. The distribution of velocities, temperatures, and pressure in inter-tube channels have been obtained.
Do ionic liquids replace water or nanofluids to enhance heat transfer in micro-channel systems?
Authors: Al-Asadi Mushtaq T. , Al-Sallami Waleed T.
Published: November 2018

This study explores the influence of different fluids in a uniform micro-channel geometry on conjugate heat transfer. Nanofluids used here, are SiO2 and Al2O3 nanoparticles with various concentrations up to 4% in water as a base fluid under laminar flow. Nanofluids are compared to an ionic liquid called Butyl Methyl Imidazolium Tetrafluroborate (BMIM BF4) to examine the influence of heat transfer and fluid flow characteristics. Good agreement was found against previous micro-channel studies, numerical simulations with COMSOL Multiphysics® V5.2a are used at Reynolds number ranging from 50 to1000 with a uniform heat flux of 100 W/cm2 relevent to cooling systems. Advanced fluids might offer significant potential in combatting the challenges of heat transfer in the technological drive toward lower weight/smaller volume electrical and electronic devices. The results show that the lowest thermal resistance is for nanofluids followed by water, then the ionic liquid. Moreover, Al2O3-water offers lower thermal resistance than the SiO2-water for all given nanoparticle concentrations. It is also found that there is no beneficial using ionic liquids in forced convection systems which work below boiling temperature conditions.
CFD analysis of a one-pass photovoltaic/thermal air system with and without offset strip fins
Authors: Al-Damook Moustafa , Dixon-Hardy Darron , Heggs Peter J. , Al Qubeissi Mansour , Al-Ghaithi Khaled , Mason Patrick E. , Cottom Joshua
Published: November 2018

The focus on managing PV panel temperature has undergone a remarkable development in the last two decades. Specifically, in countries with moderate weather temperature and high insolation, the problem of keeping the PV cell temperature in an optimal range has been managed by use of PV/T collectors. In this work, a single pass PV/T collector using laminar air flow has been assessed. Two PV/T collector designs are utilised, one with and one without offset strip fins. COMSOL Multiphysics v5.3a has been used for the analysis of the thermal and electrical performances. Two assumptions were implemented in order to reduce the computational time from 95 hours to 7 hours, namely ignoring radiative effects between the fins and the wall channels, and representing thin layers as 2D boundaries, whilst ensuring a high level of conformity (4%),. Monocrystalline silicon PV cells were used with a power temperature coefficient of 0.41%. A validation against work in the literature was made, showing a good consistency. The objective of this work is to verify the performance of the air PV/T collector with offset strip fins compared to an unfinned air PV/T collector. The results reveal that the use of offset strip fins has a noticeable impact on both the electrical and thermal efficiencies of the system. In addition, the maximum combined efficiency (ηCo) for the finned PV/T system is 84.7% while the unfinned PV/T system is 51.2%.
Experimental studies of two-phase liquid metal-gas chain flow with ultrasonic echo pulse method and in the magnetic field of permanent magnets
Authors: Andruszkiewicz Artur , Eckert Kerstin
Published: November 2018

Metallurgical processes of refining and degassing liquid metals are related to the blowing-in neutral gasses like for example argon. Effectiveness of the process depends on the flowing gas parameters like: dimensions, velocity, distribution amd gas phase flow zone. These parameters can be changed under the influence of outside magnetic field and formed by it a Lorentz’ force. In order to get full information of rising bubbles essential are certain measuring methods. Among many of these the ultrasonic echo pulse method is likely to be the most intensive developed in the past few years. That method enables estimation of gas phase flow parameters in a range from individual bubble flow up to full continuous gas flow at the inlet nozzle. In this paper a measurement principle has been described for an ultrasonic echo method and there also submitted and discussed results of obtained results for diphase flow of GaInSn-argon.
Meshing strategy for hybrid tet-hex PHES layered bed heat storage
Authors: Mosiężny Jçdrzej , Ziegler Bartosz
Published: November 2018

Article describes a meshing strategy for efficient computation of generic layered heat storage device for pumped heat energy storage (PHES). Mesh for structural solid body and fluid boundary layer is with unstructured flow field is presented. A rationale for geometry choice, mesh topology and different types of mesh topologies considered in this study. The effect of coarse and fine mesh on computational time and accuracy of results for transient analysis of coupled fluid and heat flow is described.
Computational analysis of a cross flow turbine performance
Authors: Gómez Vanessa Ruiz , Higuita Edison A. Palacio , Morán Aldo Germán Benavides
Published: November 2018

In the electrical energy generation context in Colombia, the water resources represent the 64% of the potential generated according to UPME in the 2015 year; becoming into a solution to the growing energy demand and to the supply of energy in non-interconnected zones. The cross-flow turbines as Michell-Banki type, become an efficient and economically attractive choice. This paper shows the fluiddynamic performance of a laboratory’s model turbine under several operating conditions. The development of this analysis is supported by the results of experimental tests, uses the computational fluid dynamics as a tool for modelling, estimate, and analyse the turbine behaviour under different operating conditions, with ANSYS-Fluent software; the computational model considers the most important geometric aspects of the turbine and the opening percentage effect of the guide blade. The water flow through the rotor is approach through a turbulence model as κ – ε type. The numerical study results agree satisfactorily with the turbine performance observed in the laboratory.
Influence of crystal growth kinetics on prediction of macro segregation by micro-macroscopic simulation of binary alloy solidification
Authors: Seredyñski Mirosław , Banaszek Jerzy
Published: November 2018

Using the micro-macroscopic computer simulation model of binary alloy solidification, based on a single domain control-volume calculations, and involving the tracking of columnar dendrite tips envelope for distinguishing different grain structures within the two-phase liquid-solid region, the paper reports the outcomes of the detailed analysis addressing the question of the influence of enhanced KGT crystal growth models on the predicted macro-segregation pattern in the Al-4wt.%Cu alloy cast. In particular, the analysis concerns the impact of a proper selection of the stability constant for the KGT model (based on a crystal-melt surface energy anisotropy strength and linear scaling law of the marginal stability theory) on the predicted dendrite tip under-cooling, volumetric solid fraction and actual solute concentration along the front of columnar dendrite tips. Differences in the resulting evolution of both: the under-cooled melt region within the mushy zone and the solute concentration fields calculated for the considered various kinetics of a grain growth are also reported and discussed.
Effect of viscous dissipation in two-dimensional Stokes flow between rotating cylinders – preliminary numerical investigation
Authors: Teleszewski Tomasz Janusz
Published: November 2018

This paper introduces the modelling of two-dimensional laminar flow of Newtonian fluid in a system of concentric or eccentric rotating cylinders with regards to viscous dissipation. Viscous dissipation is a main part, where the viscosity is large for example in oils. The dependence of the Nusselt number on the ratio of the radius of the inner cylinder to the radius of the external cylinder for the selected distance of the cylinder axes was investigated. In order to determine the velocity fields and the temperature distribution, the boundary element method was used. The results of the calculations were presented in the form of diagrams.
Numerical study of an asymmetrically heated rectangular duct with suspended cylinders
Authors: Chhaparwal Gaurav Kumar , Srivastava Ankur , Dayal Ram
Published: November 2018

An asymmetrically heated (only one side of the duct is heated) solar air heater duct is numerically investigated using openFOAM to study the effect of passive turbulators (suspended cylinders) installed within the boundary layer close to the absorber plate to enhance heat transfer from it. Vortex flow is created behind the suspended cylinders, which disturbs the boundary layer and causes mixing of hot stream lines near the surface with relatively cold stream away from the absorber plate. Diameter of the suspended cylinders and its distance from the absorber plate is varied to study its effect on wall temperature of absorber plate in the turbulent flow regime.
Simulation of water turbine integrated with electrical generator
Authors: Borkowski Dariusz , Węgiel Michał , Ocłoñ Paweł , Węgiel Tomasz
Published: November 2018

The paper presents the analysis of the small hydropower plant working at variable speed. The hydro-set that consists of the guide vanes and propeller turbine integrated with the permanent magnet synchronous generator is simulated by using Computational Fluid Dynamics (CFD) in Ansys Fluent v18.0. The k-ε and k-ω SST models, as well as the one-equation Spalart-Allmaras (SA) model, were tested. The comparison showed the significant divergence of the calculation results. The turbulence model selection influences the average value of the power and also the speed for which the power is maximal.
A model of the novel concept liquid piston engine sourced by waste heat
Authors: Bujalski Wojciech , Futyma Kamil , Milewski Jarosław , Szczęśniak Arkadiusz
Published: November 2018

This paper describes the model of the novel concept liquid piston engine, which is designed to convert low-grade waste heat into electricity. The proposed dynamic oriented model is implemented in Aspen Hysys that enables simulations dynamic simulation of various working agents. The simulation results were verified with experimental data obtained from the research installation. The proposed model demonstrated relatively small discrepancies with respect to experimental research, hence it could be used as a tool for research on optimization of an innovative power plant operation, i.e. various working agents, various operating pressures.
Shape and operation optimization of a thick-walled power boiler component
Authors: Duda Piotr , Mrzygłód Mirosław W.
Published: November 2018

The aim of this article is the proposition of a two-stage optimization of power boiler components subjected to transient thermo-mechanical loads. As the basis of transient load regime, the TRD 301 regulations are used. In the first stage of an investigation, the genetic algorithms are used to determine the optimal shape of the structure. As optimization constraints, the maximum total stresses in the whole cycle are assumed. In the next stage, the method for the start-up and shut-down operation optimization is shown. The problem is defined to minimize the time of start-up and shut-down processes with allowable stress constraints according to TRD regulations. These new methods are of high practical significance and can be implemented throughout the industry, wherever heating and cooling processes take place. The obtained optimization results translate directly into the power unit energy effectiveness because the shut-down and start-up losses are reduced.
An analysis of high-temperature nuclear reactor coupled with gas turbine combined cycle
Authors: Jaszczur Marek , Dudek Michał , Śliwa Tomasz , Kolenda Zygmunt
Published: November 2018

At present many companies from the energy sector have to follow new regulations and concerns three crucial aspects of energy production: the impact on the environment, the efficiency of energy conversion and the cost of energy. From a technical point of view, the most efficient technology available today for electricity generation is based on a gas turbine combined cycle. In the present paper, an analysis of environmentally friendly, high-temperature gas nuclear reactor system coupled with gas turbine combined cycle technology has been investigated. The analysed system is one of the most advanced concepts and allow electricity generation with the higher thermal efficiency than could be offered by any currently existing nuclear power plant technology. The results show that it is possible to achieve thermal efficiency for nuclear power plant higher than 50% which is not only more than could be produced by any modern nuclear plant but it is also more than could be offered by most of the traditional power plants.
Modeling of a re-heat two-stage adsorption chiller by AI approach
Authors: Krzywanski Jaroslaw , Grabowska Karolina , Sosnowski Marcin , Żyłka Anna , Sztekler Karol , Kalawa Wojciech , Wójcik Tadeusz , Nowak Wojciech
Published: November 2018

A distinct advantage of adsorption chillers is their ability to be driven by heat of near ambient temperature. However the performance of the thermally driven adsorption systems is lower than that of other heat driven heating/cooling systems. It is the result of a poor heat transfer coefficient between the bed and the immersed heating surfaces of a built-in heat exchanger system. The aim of this work is to study the effect of thermal conductance values as well as other design parameters on the performance of a re-heat two-stage adsorption chiller. One of the main energy efficiency factors in cooling production, i.e. cooling capacity (CC) for wide-range of both design and operating parameters is analyzed in the paper. Moreover, the work introduces artificial intelligence (AI) approach for the optimization study of the adsorption cooler. The Adaptive Neuro – Fuzzy Inference System (ANFIS) was employed in the work. The developed ANFIS model can be applied for optimizations purposes and may constitute a submodel or a separate module in engineering calculations, capable to predict the CC of the re-heat two-stage adsorption chiller.
Study of Chlorella vulgaris sedimentation process
Authors: Patyna Agnieszka , Płaczek Małgorzata , Witczak Stanisław
Published: November 2018

The paper reports the results of Chlorella vulgaris sedimentation process including description of cultivation condition of microalgal biomass. The process of algae cultivation was carried out in photobioreactor comprising systems of carbon dioxide supply, mixing and artificial LED illumination. The growth of microalgae was determined alternatively in three ways by measuring the amount of dry mass over time, counting the cells and measurement of optical density by use of a spectrophotometer. Algae biomass with different concentration was subjected to the separation process by gravity. This led to the determination of the characteristic of sedimentation process for different concentrations and cell sizes. The experimental results indicate that sedimentation process offers a tool with a potential application for microalgae harvesting.
The PeaMUST project: defining ideotypes for the pea crop development
Authors: Burstin Judith , Rameau Catherine , Bourion Virginie , Tayeh Nadim
Published: November 2018

Pea is the most widely cultivated grain legume crop in Europe. In the French research project PeaMUST, a large public and private sector partnership has been set up to undertake complementary strategies towards the development of high and stable yielding cultivars. These different strategies will contribute to the definition of a pea ideotype based on both a priori and a posteriori approaches. On the one hand, genomic selection will identify interesting genotypes which may display new phenotypic ideotypes. On the other hand, marker-assisted selection will enable cumulating resistance for a given or different stresses to reach more durably stable phenotypes. Moreover, mutations identified in candidate genes controlling aerial and root architecture will be tested for their effects on stress tolerance.
Beckner inequalities for Moebius measures on spheres
Authors: Yao Nian , Zhang Zhengliang
Published: November 2018

In this paper, we consider the Moebius measures μxn indexed by dimension n and |x| < 1 on the unit sphere Sn−1 in ℝn (n ≥ 3), and provide a precise two-sided estimate on the order of the Beckner inequality constant with exponent p ∈ [1, 2) in the three parameters. As special cases for p = 1 and p tending to 2, our results cover those in Barthe et al. [Forum Math. (submitted for publication)] for n ≥ 3 and explore an interesting phenomenon.
A Markov decision model with dead ends for operating room planning considering dynamic patient priority
Authors: Zhang Jian , Dridi Mahjoub , El Moudni Abdellah
Published: November 2018

This paper addresses an operating room planning problem with surgical demands from both the elective patients and the non-elective ones. A dynamic waiting list is established to prioritize and manage the patients according to their urgency levels and waiting times. In every decision period, sequential decisions are taken by selecting high-priority patients from the waiting list to be scheduled. With consideration of random arrivals of new patients and uncertain surgery durations, the studied problem is formulated as a novel Markov decision process model with dead ends. The objective is to optimize a combinatorial cost function involving patient waiting times and operating room over-utilizations. Considering that the conventional dynamic programming algorithms have difficulties in coping with large-scale problems, we apply several adapted real-time dynamic programming algorithms to solve the proposed model. In numerical experiments, we firstly apply different algorithms to solve the same instance and compare the computational efficiencies. Then, to evaluate the effects of dead ends on the policy and the computation, we conduct simulations for multiple instances with the same problem scale but different dead ends. Experimental results indicate that incorporating dead ends into the model helps to significantly shorten the patient waiting times and improve the computational efficiency.
The effect of full or partial pricing integration on supply chain management
Authors: Shih Neng-Hui , Shu Ming-Hung , Wang Chih-Hsiung
Published: November 2018

A previous paper proposed a supply chain model, comprised of a retailer and manufacturer, in which the manufacturer uses product pricing to maximize the profit of the entire supply chain. The increased profits gained from integration are then shared among all the supply chain members. The optimal pricing strategy was shown to be “products on consignment” for sale. The present study extends this simple two-layer supply chain model to a more complicated three-layer model, in which the supply chain comprises not only the retailer and manufacturer, but also an intermediate distributor. In contrast to the previous model, the present model not only considers the role of the distributor, but also the effects of product nonconformance at each facility in the supply chain. The profit function of each facility in the supply chain is established, including the sales revenue, procurement cost, and quality control cost. The investment cost at the retailer to improve the service level is also considered. It is shown that the total profit of the supply chain is maximized when the retailer’s optimal service level is adopted, where this service level is adjusted in accordance with the distributor’s unit sale price. Furthermore, after price integration, the overall profit of the supply chain is found to equal the retailer’s profit. In other words, the total profit of the manufacturer and distributor is equal to zero. Numerical examples are given to illustrate the proposed pricing integration model under different quality environments. The results are contrasted with those obtained using a traditional pricing model, namely the “make up on cost’’ model. Overall, the present results show that the manufacturer is always the winner under partial price integration (i.e., only the retailer and distributor join the integration). Furthermore, partial integration is far less profitable for the retailer and distributor than full integration.
Seasonal Difference in Bone Characteristics and Body Composition of Elite Speed Skaters
Authors: Varley Ian , Greeves Julie , Sale Craig
Published: November 2018

We investigated the changes in bone characteristics and body composition of elite speed skaters across two competitive seasons. Twelve elite speed skaters (age 23±4 years; height 1.73±0.09 m; body mass 68.5±8.8 kg; mean±1 SD) were assessed by DXA and pQCT for Bone Mineral Density (BMD), Bone Mineral Content (BMC), area, bone strength, cortical thickness and density at four points over the course of four competitive seasons. Body composition data was also collected. A main effect of time was shown for whole body BMC, right leg BMC, and trabecular area (P<0.05). Whole body BMC was higher during pre-season and end of season in comparison to mid-season (1.0%, P=0.007; 0.8%, P=0.017), right leg BMC was higher at the pre-season scan in comparison to the post pre-season scan (1.8%,P=0.020) and trabecular area was higher during the mid-season and end of season when compared to the pre-season (1.4%, P=0.012; 1.0%, P=0.003). Seasonal changes in bone characteristics and body composition are shown in elite speed skaters over a competitive season. The changes are thought to be a result of fluctuations in training load. These data may have implications for training design and injury risk management in elite sport.
Fun with (4+3)-Cycloadditions
Authors: Harmata Michael
Published: November 2018

This account describes how I began my adventure in the area of (4+3)-cycloadditions and then focuses on two ongoing projects: a new catalytic asymmetric (4+3)-cycloaddition and what might be described as the ‘rebirth’ of oxidopyridinium ion (4+3)-cycloaddition chemistry. References to other people’s work are made where appropriate.

1 Introduction

2 Asymmetric, Catalytic (4+3)-Cycloadditions

3 Oxidopyridinium Ions and (4+3)-Cycloadditions

4 Conclusions and the Future
Tris(acetylacetonato) Iron(III): Recent Developments and Synthetic Applications
Authors: Lübken Dennis , Saxarra Marius , Kalesse Markus
Published: November 2018

Tris(acetylacetonato) iron(III) [Fe(acac)3] is an indispensable reagent in synthetic chemistry. Its applications range from hydrogen atom transfer to cross-coupling reactions and to use as a Lewis acid. Consequently, the exceptional utility of Fe(acac)3 has been demonstrated in several total syntheses. This short review summarizes the applications of Fe(acac)3 in methodology and catalysis and highlights its use for the synthesis of medicinally relevant structures and in natural product syntheses.

1 Introduction

2 Hydrogen Atom Transfer (HAT)

3 Oxidations and Radical Transformations

4 Synthesis and Use of Alkynes and Allenes

5 Cross-Couplings and Cycloisomerizations

6 Borylations

7 Miscellaneous Reactions

8 Conclusions
A [3+2] Cyclization of Siloxyalkynes and Isocyanides for the Synthesis of Oxazoles
Authors: Wu An , Sun Jianwei
Published: November 2018

A mild and efficient [3+2] cyclization of siloxyalkynes for the synthesis of aromatic heterocycles is developed. It is a new addition to the cyclization reactions of these versatile species. In the presence of TBAF as promoter, siloxyalkynes react with electron-withdrawing isocyanides to form a range of oxazole products. In this reaction, siloxyalkynes contribute the C–O unit for the cyclization, which is different from previous typical examples where it is a two-carbon contributor. Mechanistic studies provided insights into the mechanism, which involves a ketene intermediate. Based on the mechanistic insight, an alternative catalytic system was also demonstrated to be effective for the same transformation.
4-(N,N-Dimethylamino)pyridine (DMAP)-Catalyzed 1,3-Dipolar Cycloaddition of 3-Aminooxindole-Based Azomethine Ylides with α,β-Unsaturated Acyl Phosphonates for the Construction of Spiropyrrolidinyl-2,3′-oxindoles
Authors: Chen Zhuo , Chen Lin , He Jin , Sun Rong-Guo , Fan Li , Tian Shi-Yan , Huang Ting-Ping
Published: November 2018

A novel, one-pot 1,3-dipolar cycloaddition of 3-amimooxindole-based azomethine ylides with α,β-unsaturated acyl phosphonates and subsequent derivatization of the intermediates is described. Employing 4-(N,N-dimethylamino)pyridine (DMAP), an organic Brønsted base, as a robust catalyst leads to an architecturally diverse set of spiropyrrolidinyl-2,3′-oxindoles bearing four contiguous stereocenters and an ester or an amide at the γ-position of the pyrrolidine motif. The products are obtained in moderate to excellent yields and with good diastereoselectivities under mild conditions. The potential of this methodology is demonstrated through a gram-scale reaction and a further transformation of one of the products.
Novel Application of Steroid Eluting Stent in Petrous Apex Cholesterol Granuloma
Authors: Choi Kevin J. , Jang David W. , Zomorodi Ali R. , Codd Patrick J. , Friedman Allan , Abi Hachem Ralph
Published: November 2018

Objective This study describes the safety and efficacy of mometasone furoate eluting stents in the management of petrous apex cholesterol granuloma approached through an endonasal endoscopic route and assesses the restenosis rate.

Methods Consecutive patients undergoing endoscopic endonasal marsupialization of a petrous apex cholesterol granuloma at a tertiary referral center who had a mometasone furoate eluting stent placed intraoperatively were reviewed in a retrospective fashion. Postoperative endoscopy was used to determine success of surgery and stenting.

Results Five patients were included in the study, three were primary cases and two patients had revision surgeries performed. The steroid eluting stent was placed successfully and safely in all patients with no dural or vascular injuries. The average follow-up duration was 10.6 months. There was no restenosis in three patients and one patient had an immediate restenosis that was debrided in clinic (revision case). This was patent at the 16 months follow-up. One patient also developed stenosis, 4 months after surgery due to sphenoid sinusitis.

Conclusion Mometasone furoate eluting stents are safe and effective in the primary management of petrous apex cholesterol granuloma. Further studies are needed to assess their efficacy in revision cases and for long term results.
Role of Splenic Artery Embolization in Gastric Variceal Hemorrhage due to Sinistral Portal Hypertension
Authors: Sebastian Bibin , Singhal Soumil , Madhurkar Rohit , Alex Arun , Uthappa M.
Published: November 2018

Sinistral or left-sided portal hypertension is a localized form of portal hypertension usually due to isolated obstruction of splenic vein. Most commonly, it is secondary to pancreatitis. Rarely this can present as life-threatening gastric variceal bleeding. In such patients, splenectomy is traditionally considered as the treatment of choice to relieve venous hypertension. Unfortunately, a surgical operation may not be safe in most of the patients because of the unfavorable operative field. Splenic artery embolization (SAE) is an effective method, theoretically akin to splenectomy, blocking the direct arterial inflow to the spleen and thereby reducing the outflow venous pressure. The authors demonstrate a case of a 58-year-old man who presented with severe gastric variceal hemorrhage due to sinistral portal hypertension (SPH) secondary to an episode of pancreatitis, which he had 1 month back. He was successfully managed by SAE and remains symptom-free. The authors bring to the fore the potential curability of gastric variceal hemorrhage secondary to SPH using SAE, which is a safe and effective interventional radiologic procedure.
Partial Splenic Artery Embolization for the Treatment of ITP: A Case Series-Pilot Study
Authors: Thomas Mathew , Yadav Manish , George Elsa
Published: November 2018

The purpose of this pilot study was to assess the effectiveness of partial splenic artery embolization (PSE), in the treatment and management of immune thrombocytopenia (ITP). Six patients with ITP who underwent PSE were followed up. The condition was either refractory to medications like steroids, intravenous immunoglobulin, immunosuppressants, or required very high doses of these drugs which could not be tapered down. Five out of six patients did not have good response even after adding immunosuppresants to steroids. The 6 patients who underwent PSE were followed up to 7 to 18 months with an average duration of 3.5 years. A therapeutic effect was defined as a platelet count of > 10,000/cumm (level below which spontaneous bleeding is likely to occur) at the last follow-up date with marked decrease in drug dosage. A good response was seen in all the patients – their doses of drugs could be reduced considerably and all had platelet count well above 10,000 during the last follow up after PSE. None of the patients who underwent embolization had any serious complications.