bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Activation Mechanism and Sustainable Development of Rural Human Settlements Based on Landscape Construction
Authors: Xin Sui , Lin Lin , Chaoyang Sun
Published: June 2018

The quality of rural human settlement environment is directly related to the quality of urban human settlements, which is a big problem in the development of China's social economy. In the special period of social transformation and the key stage of building a well-off society comprehensively, it is of great practical significance to pay attention to the optimization of rural human settlement environment. China is in the transition from traditional rural landscape to modern rural landscape. However, how to realize the smooth transformation and the sustainable development of rural landscape is urgent and tough issues.
Research progress on modification of activated carbon
Authors: Liu Mengran , Xiao Cong
Published: June 2018

The paper overall the way and principle of how to modify activated carbon at home and abroad. Besides, the characteristics was given on physical, chemical modification respectively. The physical modification generally changed internal and external structure of the activated carbon, while chemical modification changed both its structure and surface properties. The advantages, disadvantages and the mechanism of the modifiers mentioned above are discussed, and their application are also prospected.
Effects of Different Material Total Solid on Biogas Production Characteristics
Authors: Sun Yu-Ming , Huang Xiao-Mei , Kang Yin-Hu
Published: June 2018

In China, livestock manure emission has resulted in severe pollution to the environment and it is an efficient spreading agent of diseases. For this reason, the biogas has gotten a rapid development in the past few decades. As a kind of renewable and clean energy, many studies have indicated the prospect of biogas to replace fossil fuels in the future. However, the methane industrial production process is unstable due to various factors. Therefore, it is necessary to enhance the biogas fermentation efficiency. In this paper, the influences of the raw materials and the total solids (TS) concentration on biogas production characteristics are studied, where the utilization of raw materials can be reflected by the biogas production rate in the results. The results showed the anaerobic fermentation cycle is prolonged and biogas yield increases, but the utilization decreases with TS increases.
Optimization of extraction of chitin from procambarus clarkia shell by Box-Behnken design
Authors: Dong Fang , Qiu Hailong , Jia Shaoqian , Dai Cuiping , Kong Qingxin , Xu Changliang
Published: June 2018

This paper investigated the optimizing extraction processing of chitin from procambarus clarkia shell by Box-Behnken design. Firstly, four independent variables were explored in single factor experiments, namely, concentration of hydrochloric acid, soaking time, concentration of sodium hydroxide and reaction time. Then, based on the results of the above experiments, four factors and three levels experiments were planned by Box-Behnken design. According to the experimental results, we harvested a second-order polynomial equation using multiple regression analysis. In addition, the optimum extraction process of chitin of the model was obtained: concentration of HCl solution 1.54mol/L, soaking time 19.87h, concentration of NaOH solution 2.9mol/L and reaction time 3.54h. For proving the accuracy of the model, we finished the verification experiment under the following conditions: concentration of hydrochloric acid 1.5mol/L, soaking time 20h, concentration of sodium hydroxide 3mol/L and reaction time 3.5h. The actual yield of chitin reached 18.76%, which was very close to the predicted yield (18.66%) of the model. The result indicated that the optimum extraction processing of chitin was feasible and practical.
Design and Application of Integrated Assembly Technology of FRG in Residential Ceiling
Authors: Li Xiuyun , Yu Changyong
Published: June 2018

FRG material is a new environmentally friendly indoor decoration materials and popular in prefabricated construction, the paper introduces the performance and design of materials, and takes FRG in the residential ceiling integrated assembly process into a demonstration project, which showed that FRG in the prefabricated modules integrated ceiling of the whole template scheme has a great artistry and application effect. Meanwhile it provides reference for the integrated ceiling assembly modular process design of similar indoor decoration.
Enhanced photocatalytic activity of wool-ball-like TiO2 microspheres on carbon fabric and FTO substrates
Authors: Zhang Yu , Gu Jian , Zhang Mengqi
Published: June 2018

The wool-ball-like TiO2 microspheres on carbon fabric (TiO2-CF) and FTO substrates (TiO2-FTO) have been synthesized by a facile hydrothermal method in alkali environment, using commercial TiO2 (P25) as precursors. The XRD results indicate that the as-prepared TiO2 have good crystallinity. And the SEM images show that the wool-ball-like TiO2 microspheres with a diameter of 2-3 μm are composed of TiO2 nanowires, which have a diameter of ~50 nm. The photocatalytic behavior of the wool-ball-like TiO2 microspheres, TiO2-CF and TiO2-FTO under ultraviolet light was investigated by a pseudo first-order kinetic model, using methyl orange (MO) as pollutant. The wool-ball-like TiO2 microspheres obtained a degradation rate constant (Kap) of 6.91×10-3 min-1 . The Kap values of TiO2-FTO and TiO2-CF reach 13.97×10-3 min-1 and 11.80×10-3 min-1, which are 2.0 and 1.7 times higher than that of pristine wool-ball-like TiO2 microspheres due to the “sum effect” between TiO2 and substrates. This study offers a facile hydrothermal method to prepare wool-ball-like TiO2 microspheres on CF and FTO substrates, which will improve the recyclability of phtocatalysts and can be extended to other fields.
Structures and Properties of Self - crosslinking Silicone Resin
Authors: Zhao Yong-xin , Zhang Ying-qiang
Published: June 2018

Highly transparent silicone resin with self-crosslinking structure was prepared using phenyltrimethoxysilane, diphenyldimethoxysilane, 1,3,5,7-cyclotetra(methyl siloxane) and bisvinyltetramethyldisiloxane as main raw materials. The structure of silicone resin was determined by Fourier Transform Infrared Spectroscopy (FT-IR). The light transmittance was measured by UV-Vis spectroscopy. Thermogravimetric analysis (TGA) was used to study the thermal decomposition process. The microstructure of cured self-crosslinking silicone resin is more uniform, resulting in better light transmittance up to 100% in the range of 400nm ~ 800nm. The cured has relatively good heat resistance, the initial thermal decomposition temperature of the cured could be up to 315.8 °C. SEM observations show that the self-crosslinking silicone has a uniform, textured structure, higher transparency compared with the existing condensation silicone material, and can be used as advanced architectural translucent materials and optics packaging materials.
Theoretical Analysis for Local Buckling of Corrugated Steel Plate
Authors: Li Bai Jian , Zhu Liang Sheng , Fu Xin Sha
Published: June 2018

To study local buckling of Corrugated Steel Plate under concentrated loads. Through experimental tests and theorical analysis, bearing capacity and failure form of Corrugated Steel Plate were discussed. Bearing capacity of Corrugated Steel Plate associated with local buckling, which can be assumed to be composed of three parts: buckling of plane rigid frame caused by concentrated loads, buckling of roof and web caused by bending stress. These three parts were unified by buckling relevant equations, then local buckling calculation formula was obtained. Comparing with experimental results, the loads obtained by local buckling calculation formula agree with test results very well. Since the buckling calculation is independent of the material strength, the calculation formula of local buckling is reliable, it can be used to evaluate local buckling of Corrugated Steel Plate.
A Review of Research on Human-induced Vibration Serviceability and Dynamic Properties of Long-span Floor
Authors: Cao Li Lin , Qian Cheng , Chu Lan Zhe , Yu Guo Jun
Published: June 2018

Studies on the dynamic properties of long-span floor is an essential basis for a solution to the problem of human-induced vibration serviceability. According to the recent research, this review introduces the application of numerical simulation in the research of dynamic properties and summarizes the modeling method of sophisticated finite element model. The reliability of the finite element model is verified by the field test and model test. Comparing the application of studies on dynamic properties among numerical simulation and model test, the differences between numerical simulation and model test are summarized. Finally, some problems that need further study are proposed.
Study on Human-structure Dynamic Interaction in Civil
Engineering
Authors: Gao Feng , Cao Li Lin , Li Xing Hua
Published: June 2018

The research of human-structure dynamic interaction are reviewed. Firstly, the influence of the crowd load on structural dynamic characteristics is introduced and the advantages and disadvantages of different crowd load models are analyzed. Then, discussing the influence of structural vibration on the human-induced load, especially the influence of different stiffness structures on the crowd load. Finally, questions about human-structure interaction that require further study are presented.
Research on the Method of Setting Waiting Area for Non-motor Vehicle at Signal Control Intersection
Authors: Wang Yun Xia , Liu Dong Bo
Published: June 2018

Electric bicycle has become an indispensable important component of the transportation system. The fact is that traffic organization and channelizing design of signal control intersection is not intensive, which cannot adapt to the current traffic demand of non-motor vehicle, such as unclear traffic rules and poor visibility, thus the traffic safety of non-motor vehicle is not optimistic. Therefore, it is necessary to study on traffic organization method based on the demand of non-motor vehicle, which can provide certain theoretical basis for traffic administrative department to make policy and traffic design. This article focuses on the method of setting waiting area for non-motor vehicle at signal control intersection, including the advantages, disadvantages and the applicable conditions.
Exploratory Research on Bearing Characteristics of Confined Stabilized Soil
Authors: Wu Shuai Shuai , Gao Zheng Guo , Li Shi Yang , Cui Wen Bo , Huang Xin
Published: June 2018

The performance of a new kind of confined stabilized soil (CSS) was investigated which was constructed by filling the stabilized soil, which was made by mixing soil with a binder containing a high content of expansive component, into an engineering plastic pipe. Cube compressive strength of the stabilized soil formed with constraint and axial compression performance of stabilized soil cylinders confined with the constraint pipe were measured. The results indicated that combining the constraint pipe and the binder containing expansion component could achieve such effects: higher production of expansive hydrates could be adopted so as to fill more voids in the stabilized soil and improve its strength; at the same time compressive prestress built on the core stabilized soil, combined of which hoop constraint provided effective radial compressive force on the core stabilized soil. These effects made the CSS acquire plastic failure mode and more than twice bearing capacity of ordinary stabilized soil with the same binder content.
Prediction of Surface Subsidence Caused by Rectangular Pipe Jacking Construction
Authors: Zhang Chao , Jia Qi Jun , Xu Ri Qing , Feng Su Yang
Published: June 2018

Based on the development of rectangular pipe jacking, the characteristics of rectangular pipe jacking are introduced. The difference between surface settlements caused by rectangular pipe jacking is calculated by stochastic medium method and peck formula method. The influence of section shape on rectangular pipe jacking is analyzed. The results show that the calculation results of the stochastic medium method are more reasonable.
Modal Parameter Identification and Numerical Simulation for Self-anchored Suspension Bridges Based on Ambient Vibration
Authors: Liu Bing , Sun Li Guo
Published: June 2018

This paper chooses the Nanjing-Hangzhou high speed overbridge, a self-anchored suspension bridge, as the research target, trying to identify the dynamic characteristic parameters of the bridge by using the peak-picking method to analyze the velocity response data under ambient excitation collected by 7 vibration pickup sensors set on the bridge deck. The ABAQUS is used to set up a three-dimensional finite element model for the full bridge and amends the finite element model of the suspension bridge based on the identified modal parameter, and suspender force picked by the PDV100 laser vibrometer. The study shows that the modal parameter can well be identified by analyzing the bridge vibration velocity collected by 7 survey points. The identified modal parameter and measured suspender force can be used as the basis of the amendment of the finite element model of the suspension bridge. The amended model can truthfully reflect the structural physical features and it can also be the benchmark model for the long-term health monitoring and condition assessment of the bridge.
Research and Development Status of Grouted Splice Sleeve in Precast Concrete Structure
Authors: Wu Ying Chang , Sheng Liu Peng , Zhao Wei Jian
Published: June 2018

The development of precast concrete structure is an effective way to promote industrialization of construction industry and housing industrialization, and is also a inevitable choice for green development. Grouted splice sleeve connector, regarded as one of the key technologies of precast concrete structure, has the advantages of high strength and good seismic performance. In this paper, the development of grouted splice sleeve connector is systematically summarized both home and abroad, existing problems in the domestic research of sleeve are evaluated and analyzed, and corresponding countermeasures are also further proposed.
Experimental Research of FRP Composite Tube Confined Steel-reinforced Concrete Stub Columns Under Axial Compression
Authors: Wang Ji Zhong , Cheng Lu , Wang Xin Pei
Published: June 2018

A new column of FRP composite tube confined steel-reinforced concrete (FTCSRC) column was proposed. This paper elaborates on laboratorial and analytical studies on the behavior of FCTSRC columns subjected to axial compressive load. Eight circular FTCSRC stub columns and one circular steel tube confined concrete (STCC) stub column were tested to investigate the failure mode and axial compression performance of circular FTCRSC columns. Parametric analysis was implemented to inquire the influence of confinement material (CFRP-steel tube or CFRP-GFRP tube), internal steel and CFRP layers on the ultimate load capacity. CFRP-steel composite tube was composed of steel tube and CFRP layer which was wrapped outside the steel tube, while CFRP-GFRP composite tube was composite of GFRP tube and CFRP layer. The test results indicate that the confinement effect of CFRP-steel tube is greatly superior to CFRP-GFRP tube. The ductility performance of steel tube confined high-strength concrete column can be improved obviously by encasing steel in the core concrete. Furthermore, with the increase in the layers of FRP wraps, the axial load capacity increases greatly.
Numerical Analysis on Tensile Properties of Grout-filled Splice Sleeve Rebars under ISO 834 Standard Fire
Authors: Liu Yong Jun , Li Chao , Zhou When Jun
Published: June 2018

This paper presents some numerical simulation results of tensile properties of reinforcing bars spliced by grout-filled coupling sleeves under fire conditions to identify the effect of load ratio on fire resistance time of spliced reinforcing bars, which provide a useful base for predicting structural behaviors of pre-cast reinforced concrete buildings in fires. A spliced rebar system investigated in this paper consists of two equal-diameter steel reinforcing bars with 25mm diameter and a straight coupling sleeve with 50mm outer and 45mm inner diameters. As a result, the thickness of grout between steel bars and sleeves are 20mm. Firstly, the temperature distributions in steel bars connected by grout- filled coupling sleeves exposed to ISO 834 standard fire were calculated utilizing finite element analysis software ANSYS. Secondly, the stress changes in heated steel bars connected by grout-filled coupling sleeves under different constant tensile loads were calculated step by step until the rebar system failed due to fire. Thus, the fire resistant time of rebar spliced by grout-filled coupling sleeves under different axial tensile loads can be determined, further, the relationship between fire resistance time and axial tensile loads ratio can could be obtained. Finally, the fire resistant times versus axial tensile load ratios curve of grout-filled splice sleeve rebars exposed to ISO 834 standard fire is presented.
A Technique for Tunable Filters with Low Insertion Loss and Narrow Bandwidth
Authors: Zhou Chang , Ji Chen , Wu Gen Ping
Published: June 2018

A technique for tunable filters with low insertion loss and narrow bandwidth is proposed in the form of comb-line structure. Both resonant capacitor with pin-diodes and resonant inductance in the tunable filter were analyzed and the main source of insertion loss was obtained. A series of filters with same pin-diodes, center frequency, absolute bandwidth and low return loss was simulated. The results showed that, by changing the values of the resonant capacitor and inductance, insertion loss of the filter can be greatly restricted. This technique will allow the design of tunable LC filters with low insertion loss and narrow bandwidth.
Analysis of the typical small watershed of warping dams in the sand properties
Authors: Li Li , Yang Ji Shan , Sun Wei Ying , Shen Sha Sha
Published: June 2018

Coarse sediment with a particle size greater than 0.05mm is the main deposit of riverbed in the lower Yellow River, the Loess Plateau is one of the concentrated source of coarse sediment, warping dam is one of the important engineering measures for gully control. Jiuyuangou basin is a typical small basin in the first sub region of hilly-gullied loess region, twenty warping dams in Jiuyuangou basin was selected as research object, samples of sediment along the main line of dam from upper, middle to lower reaches of dam fields and samples of undisturbed soil in slope of dam control basin were taken to carry out particle gradation analysis, in the hope of clearing reducing capacity on coarse sediment of different types of warping dam through the experimental data. The results show that the undisturbed soil in slope of dam control basin has characteristics of standard loess, the particle size are mainly distributed in 0.025~0.05mm, and the 0.05mm particle size of Jiuyuangou basinof loess is an obvious boundary; Particle size of sediment in 15 warping dam of Jiuyuangou basin are mainly distributed in 0.031~0.05mm with the dam tail is greater than dam front in general. The separation effect of horizontal pipe drainage is better than shaft drainage for which particle size greater than 0.05mm, notch dam is for particle size between 0.025~0.1 mm, and fill dam is for particle size between 0.016 ~ 0.1 mm, they all have a certain function in the sediment sorting.
Cause Analysis and Countermeasures of a Breakdown Failure of Flexible 110 kV Cable Terminal
Authors: Huang Feng
Published: June 2018

disintegration examination and analysis are employed in flexible terminal breakdown of 110 kV XLPE insulated cables. It is considered that the main reason of breakdown is the separation of the stress cone of the terminal and the fracture of the semi- conductive layer of the cable insulation. Therefore, the finite element method is used to electric field model and simulate the dislocation fault of internal stress cone and outer semiconductor layer of cable insulation. The distribution of the electric field intensity is calculated and compared. The simulation and calculation results verify the validity of the breakdown mechanism analysis, and put forward some practical suggestions.
Temperature Drift Compensation of Eddy Current Sensor under High Temperature Environment
Authors: He Ping , Ma YunKai , Chen Hui
Published: June 2018

Eddy current sensor is an sensor based on eddy current effect. In practical engineering applications, the ambient temperature of eddy current sensor may be up to 135 ℃. The temperature drift of eddy current sensor magnifies the error of displacement detection. In this paper, the main factors that cause temperature drift are analyzed in detail, and the results show that the compensation based on single parameter can not meet the demand of high-precision measurement. For this reason, this paper proposes an external compensation method which applies mathematical fitting to realize compensation for temperature drift. The experimental results show that the measurement accuracy of the external compensation method reaches 0.25% in the working temperature range, which greatly improves the measurement accuracy of eddy current sensor under high temperature.
Experiment Comparison between Engineering Acid Dew Point and Thermodynamic Acid Dew Point
Authors: Song Jinghui , Yuan Hui , Deng Jianhua
Published: June 2018

in order to realize the accurate prediction of acid dew point, a set of measurement system of acid dew point for the flue gas flue gas in the tail of the boiler was designed and built, And measured at the outlet of an air preheater of a power plant of 1 000 MW, The results show that: Under the same conditions, with the test temperature decreases, Nu of heat transfer tubes, fouling and corrosion of pipe wall and corrosion pieces gradually deepened. Then, the measured acid dew point is compared with the acid dew point obtained by using the existing empirical formula under the same coal type. The dew point of engineering acid is usually about 40 ℃ lower than the dew point of thermodynamic acid because of the coupling effect of fouling on the acid liquid, which can better reflect the actual operation of flue gas in engineering and has certain theoretical guidance for the design and operation of deep waste heat utilization system significance.
The Fractal Characterization of Mechanical Surface Profile Based on Power Spectral Density and Monte-Carlo Method
Authors: Shen Jingfang , Gong Yuqi , Meng Hang , Yang Jiajun
Published: June 2018

The analysis of rough surface morphology plays an important role in the functional characteristics of the contact surface of mechanical parts. Fractal geometry method is more accurate and sensitive than classical statistics model. For fractal representation of rough surface, it is necessary to determine the proper fractal dimension calculation method. In this research, the effect of power spectral density method is studied based on Monte-Carlo method. The fractal dimensions are calculated, the theoretical and the calculated values are compared with paired samples. And the results are compared by non-parametric test. The result shows that power spectral density method has good characterization effect on fractal simulation contour curve. In addition, the precision of fractal dimension of power spectral density is related to fractal dimension of contour theory. The estimation methods of classical power spectral density have different application range.
Study on pricing mechanism of pumped hydro energy storage (PHES) under China’s electricity tariff reform
Authors: Zhang Fuqiang , Xu Zhicheng , Jiao Bingqi , Feng Junshu
Published: June 2018

This paper presents a pricing mechanism for pumped hydro energy storage (PHES) to promote its healthy development. The proposed pricing mechnism includes PHES pricing mechanism and cost sharing mechanism. Regarding the PHES pricing mechanism, the existed two-part tariff is still recommended to implement at the current and future stages. Regarding the cost sharing mechanism, it is suggested that the electricity capacity fee and pumping-loss fee should be all included in the allowable transmission and distribution costs of the regional power grids, which can be further transmitted to the provincial power grids. At the same time, we also suggest to exploring other funding sources to relieve the pressure of PHES cost sharing totally through the electricity sales price.
The Researches on Food Traceability System of University takeout
Authors: lu Jia xin , zhao Ce , li Zhuang zhuang , shao Zi rong , pi Kun yi
Published: June 2018

In recent years, campus takeaway has developed rapidly, and all kinds of online ordering platforms are running. The problem of distribution in the campus can not only save the time cost of the businessmen, but also guarantee the effective management of the school, which is beneficial to the construction of the standard health system for the takeout. But distribution according to the existing mode will cause certain safety and health risks. The establishment of the University takeaway food traceability system can solve this problem. This paper first analyzes the sharing mode and distribution process of campus takeaway, and then designs the intelligent tracing system for the campus takeaway; the construction of the food distribution information platform and the problem of the recycling of the green environment of the dining box. Finally, the intelligent tracing system of the school takeout is analyzed with the braised chicken as an example.
The researches on energy sustainability in Northern China
Authors: Wang Ping , Zhu Zhiqiang , Zhang Shuang
Published: June 2018

Energy, which accounts for two-thirds of today’s greenhouse gas emissions, is the key to reducing greenhouse gas emissions and slowing global warming. In this paper, the IPCC-recommended reference approach and scenario analysis were applied to evaluate dynamic change of the energy supply and energy-related carbon dioxide emissions within the period of 2000-2025 in Northern China (NC). The results show that energy importing reliance reached 85% in 2015 and the energy structure has become more diversified in NC. In addition, the per-capita CO2 emission is significantly higher while carbon intensity is lower than those of the national average. Under the LC scenario, CO2 emissions begin to fall for the first time in 2022. Hence, if Energy-Saving and Emission-Reduction strategy and regional planning for NC are implemented fully, NC will achieve the national emission reduction targets in 2025 and will have a large CO2 mitigation potential in the future.
New methodology for the heat flow prediction for different construction materials
Authors: Benachour Elhadj , Draoui Belkacem , Imine Bachir , Asnoune Khadidja , Boumediene Allaoua , Mebarki Brahim
Published: June 2018

Among the ways of energy transfer by conduction is that of molecular interaction, in which the greater motion of a molecule at a higher energy level (temperature) imparts energy to adjacent molecules at lower energy levels. This type of transfer is present, to some degree, in all systems in which a temperature gradient exists and in which molecules of a solid, liquid, or gas are present. So, in heat transfer, the thermal conductivity of a substance is an intensive property that indicates its ability to conduct heat In particular in the building sector. The thermal flux is often measured with a mathematical analysis but for the same material, on the other hand the estimate will be disruptive and sometimes very difficult when the material changes. In this paper, a single equation for predicting heat flux of different materials is given.
Space-time discontinuous Galerkin method for the numerical simulation of viscous compressible gas flow with the k-omega turbulence model
Authors: Česenek Jan
Published: June 2018

In this article we deal with the numerical simulation of the non-stationary compressible turbulent flow described by the Reynolds-Averaged Navier-Stokes (RANS) equations. This RANS system is equipped with two-equation k-omega turbulence model. The discretization of these two systems is carried out separately by the space-time discontinuous Galerkin method. This method is based on the piecewise polynomial discontinuous approximation of the sought solution in space and in time. We use the numerical experiments to demonstrate the applicability of the shown approach. All presented results were computed with the own-developed code.
Flow Dynamics in the Vicinity of Tandem Buildings
Authors: Gnatowska Renata , Kellnerová Radka , Uruba Václav
Published: June 2018

The flow-field in the vicinity of tandem building model in a wind tunnel will be subjected to analysis of dynamics. The model is 3D consisting of the two blocks of different sizes arranged in a streamwise direction. Experiments were performed using time-resolved PIV technique in several measuring planes to capture both spatial and dynamical features.
The influence of distance between vehicles in platoon on aerodynamic parameters
Authors: Gnatowska Renata , Sosnowski Marcin
Published: June 2018

The paper presents the results of experimental and numerical research focused on the reduction of fuel consumption of vehicles driving one after another in a so-called platoon arrangement. The aerodynamic parameters and safety issues were analyzed in order to determine the optimal distance between the vehicles in traffic conditions. The experimental research delivered the results concerning the drag and was performed for simplified model of two vehicles positioned in wind tunnel equipped with aerodynamic balance. The additional numerical analysis allowed investigating the pressure and velocity fields as well as other aerodynamics parameters of the test case.
Calibration of PVDF Film Transducers for the Cavitation Impact Measurement
Authors: Hujer Jan , Müller Miloš
Published: June 2018

This paper describes investigation of the influence of the protective layer thickness on the calibration sensitivity of PVDF films sensors for the cavitation impacts measurements. The PVDF film sensor is casted into an aluminium block. The drop ball method is used for the measurement of the relation between impact force and the voltage detected on the PVDF film sensor. The calibration constants are measured for three different protective layers thicknesses. Five different ball weights for 400 mm drop height are used to reach the required impact force range. The ball positions for the evaluation of the impact force are measured with a high speed camera. The voltage signal detected on the PVDF film clamps was measured with a high speed digitizer. The measured signals are analysed in LabVIEW Signal Express.
Comparison of cavitation bubbles evolution in viscous media
Authors: Jasikova Darina , Schovanec Petr , Kotek Michal , Kopecky Vaclav
Published: June 2018

There have been tried many types of liquids with different ranges of viscosity values that have been tested to form a single cavitation bubble. The purpose of these experiments was to observe the behaviour of cavitation bubbles in media with different ranges of absorbance. The most of the method was based on spark to induced superheat limit of liquid. Here we used arrangement of the laser-induced breakdown (LIB) method. There were described the set cavitation setting that affects the size bubble in media with different absorbance. We visualized the cavitation bubble with a 60 kHz high speed camera. We used here shadowgraphy setup for the bubble visualization. There were observed time development and bubble extinction in various media, where the size of the bubble in the silicone oil was extremely small, due to the absorbance size of silicon oil.
CFD analysis of optical probe interaction with wet steam flow field
Authors: Kolovratník Michal , Jun Gukchol , Bartoš Ondřej
Published: June 2018

In the frame of the measurement feasibility study of the liquid phase size distribution structure in steam turbines at intermediate and high pressures, on CTU the interaction of optical probes with the wet steam flow field is investigated. In order to validate and refine the existing knowledge, a new series of CFD simulations were performed, considering turbine flow geometry, water steam characteristics according to IAPWS97 formulation, and improved boundary conditions and quality of the computing mesh. This paper briefly presents the newly obtained results
Bulk viscosity of water in acoustic modal analysis and experiment
Authors: Kůrečka Jan , Habán Vladimír , Himr Daniel
Published: June 2018

Bulk viscosity is an important factor in the damping properties of fluid systems and exhibits frequency dependent behaviour. A comparison between modal analysis in ANSYS Acoustics, custom code and experimental data is presented in this paper. The measured system consists of closed ended water-filled steel pipes of different lengths. The influence of a pipe wall, flanges on both ends and longitudinal waves in the structural part were included in measurement evaluation. Therefore, the obtained values of sound speed and bulk viscosity are parameters of the fluid. A numerical simulation was carried out only using fluid volume in a range of bulk viscosity. Damping characteristics in this range were compared to measured values. The results show a significant influence of sound speed and subsequently, the use of sound speed value regressed from experimental data yields a better fit between the measurement and the computation.
Main rotor-body action for virtual blades model
Authors: Kusyumov Alexander , Kusyumov Sergey , Mikhailov Sergey , Romanova Elena , Phayzullin Konstantin , Lopatin Evgeny , Barakos G.
Published: June 2018

This research aims to investigate a virtual blade model and assess rotor influence on helicopter fuselage aerodynamics. The rotor disk is discretized in the azimuthal direction, and a time-varied pressure jump is applied in regions occupied by the blades. To obtain the pressure jump, an actuator disk is employed using uniform and non-uniform blade load distribution, based on momentum theory.
The high hall ventilation with the simplified simulation of the fan
Authors: Kyncl Martin , Pelant Jaroslav
Published: June 2018

Here we work with the system of equations describing the non-stationary compressible turbulent multi-component flow in the gravitational field. We focus on the numerical simulation of the fan situated inside the high hall. The RANS equations are discretized with the use of the finite volume method. The original modification of the Riemann problem and its solution is used at the boundaries. The combination of specific boundary conditions is used for the simulation of the fan. The presented computational results are computed with own-developed code (C, FORTRAN, multiprocessor, unstructured meshes in general).
The simulation of the flow through the porous media and diffusible barriers
Authors: Kyncl Martin , Pelant Jaroslav
Published: June 2018

Here we work with the RANS equations describing the non-stationary viscous compressible fluid flow. We focus on the numerical simulation of the flow through the porous media, characterized by the loss of momentum. Further we simulate the flow through the set of diffusible barriers. Here we analyze the modification of the Riemann problem with one-side initial condition, complemented with the Darcy’s law and added inertial loss. We show the computational results obtained with the own-developed code for the solution of the compressible gas flow.
Variations of flow in human airways as a consequence of lung diseases
Authors: Lizal Frantisek , Stejskal David , Belka Miloslav , Jedelsky Jan , Jicha Miroslav , Brat Kristian , Herout Vladimir , Lizalova Sujanska Elena
Published: June 2018

The efficiency of drug delivery administered by inhalation depends, among other factors, such as size and shape of aerosol particles, significantly also on the flow in the airways. As many lung diseases change both the breathing pattern and the shape of airways, we focus in this study on the influence of several selected diseases on the distribution of flow between the lung lobes and on changes the diseases induce on the course of flowrate. First, we present results of a literature survey focused on the published records of pathological breathing patterns. In the second part, we describe the newly designed breathing simulator and the implementation of the patterns into it. The last part is focused on the experimental verification of fidelity of the simulated breathing patterns.
Experimental investigation and numerical modelling of 3D radial compressor stage and influence of the technological holes on the working characteristics
Authors: Matas Richard , Syka Tomáš , Hurda Lukáš
Published: June 2018

The article deals with a description of results from research and development of a radial compressor stage with 3D rotor blades. The experimental facility and the measurement and evaluation process is described briefly in the first part. The comparison of measured and computed characteristics can be found in the second part. The last part of this contribution is the evaluation of the rotor blades technological holes influence on the compressor stage characteristics.
Modelling approaches for pipe inclination effect on deposition limit velocity of settling slurry flow
Authors: Matoušek Václav , Kesely Mikoláš , Vlasák Pavel
Published: June 2018

The deposition velocity is an important operation parameter in hydraulic transport of solid particles in pipelines. It represents flow velocity at which transported particles start to settle out at the bottom of the pipe and are no longer transported. A number of predictive models has been developed to determine this threshold velocity for slurry flows of different solids fractions (fractions of different grain size and density). Most of the models consider flow in a horizontal pipe only, modelling approaches for inclined flows are extremely scarce due partially to a lack of experimental information about the effect of pipe inclination on the slurry flow pattern and behaviour. We survey different approaches to modelling of particle deposition in flowing slurry and discuss mechanisms on which deposition-limit models are based. Furthermore, we analyse possibilities to incorporate the effect of flow inclination into the predictive models and select the most appropriate ones based on their ability to modify the modelled deposition mechanisms to conditions associated with the flow inclination. A usefulness of the selected modelling approaches and their modifications are demonstrated by comparing model predictions with experimental results for inclined slurry flows from our own laboratory and from the literature.
Inhalers and nebulizers: basic principles and preliminary measurements
Authors: Misik Ondrej , Lizal Frantisek , Asl Vahid Farhikhteh , Belka Miloslav , Jedelsky Jan , Elcner Jakub , Jicha Miroslav
Published: June 2018

Inhalers are hand-held devices which are used for administration of therapeutic aerosols via inhalation. Nebulizers are larger devices serving for home and hospital care using inhaled medication. This contribution describes the basic principles of dispersion of aerosol particles used in various types of inhalers and nebulizers, and lists the basic physical mechanisms contributing to the deposition of inhaled particles in the human airways. The second part of this article presents experimental setup, methodology and preliminary results of particle size distributions produced by several selected inhalers and nebulizers.
The computational study in the unloading slot of the control valve
Authors: Mrózek Lukáš , Tajč Ladislav , Vimmr Jan , Bublík Ondřej , Sláma Václav , Kalista Robert
Published: June 2018

The flow in the unloading system of the control valve is modelled using the numerical simulation. The proportional flow values for various widths of the slot and openings are evaluated. The changes of the pressure and Mach number in the space of the valve are recorded for the selected pressure ratios. The influence of the length of the slot on the mass flow changes is assessed. The results are compared with the experimental findings.
Effect of pore geometry of mesoporous supports on catalytic performances in methane reforming
Authors: Tannous Joy , Karam Leila , Kaydouh Marie-Nour , El Zakhem Henri , El Hassan Nissrine , Casale Sandra
Published: June 2018

Catalysts prepared using three dimensional SBA-16 silica support (composed of micropores and cage-like mesopores) were tested in the reaction of methane dry reforming, in comparison with 2D hexagonal mesoporous SBA-15 support. The samples were evaluated by N2 sorption and X-Ray diffraction (XRD) for the assessment of their textural and structural properties. The reducibility was characterized by temperature programmed reduction (TPR). The catalytic performances were evaluated in methane dry reforming and spent catalysts (after reaction) were characterized for the evaluation of sintering and coke formation by TPH/MS, XRD and HR-TEM.
A Novel Design of Water-Flow Based Electrical Generator as an Energy Harvesting Device
Authors: Ziedan Hamdy A. , Fayed Ibraheem M. , Abofard Alaa Eldin M.
Published: June 2018

This paper is aimed to investigate, experimentally, new two designs of Energy Harvesting Device: Water-Flow Based Electrical Generator (WEG). This device directly converts the motion of water inside a permanent magnet tube to electricity. Its output power is affected by several parameters such as permanent-magnet tube diameter, its length, water velocity and the concentration of minerals in the water (fresh, sewage or sea water). The relationship and dependency of these parameters are examined experimentally to obtain a set of graphs which can determine the suitability and performance of the proposed model for different applications. Advantages of these new models are clean power resource, simple and non-expensive design. The output power of these generators can power or recharge cell phones, mobile computers, radio communication equipment, stairs lighting of residential towers, commercial street signs, inside sea signs, etc.
Cooling Performance of Heat Sinks Used in Electronic Devices
Authors: Mjallal Ibrahim , Farhat Hussein , Hammoud Mohammad , Ali Samer , AL Shaer Ali , Assi Ali
Published: June 2018

Existing passive cooling solutions limit the short-term thermal output of systems, thereby either limiting instantaneous performance or requiring active cooling solutions. As the temperature of the electronic devices increases, their failure rate increases. That’s why electrical devices should be cooled. Conventional electronic cooling systems usually consist of a metal heat sink coupled to a fan. This paper compares the heat distribution on a heat sink relative to different heat fluxes produced by electronic chips. The benefit of adding a fan is also investigated when high levels of heat generation are expected.
Influence of synthesis parameters of mesocellular silica foams doped by nickel on methane reforming by CO2
Authors: Daoura O. , Boutros M. , Daoura O. , Launay F. , Massiani P. , EL Hassan N.
Published: June 2018

New catalysts based on Ni(0) dispersed onto mesocellular silica foams (MCF) were prepared for Dry Reforming of Methane (DRM). Different synthesis methods of MCF supports (with and without using NH4F or n-butanol) were tested in order to study the influence of the textural properties of the support on the catalytic performances of the catalysts. In all cases, nickel was incorporated using the double solvents method. The resulting calcined materials were characterized by N2 sorption, X-Ray diffraction (XRD) and transmission electron microscopy. Their reducibility was tested by temperature-programmed reduction (TPR). Interestingly, particularly large specific surfaces, pores diameters and pores volumes were observed when NH4F was added to the synthesis gel (MCF(N) materials). The corresponding Ni-MCF(N) catalysts were shown to be the most attractive among other prepared samples with respect to their performances in DRM.
Ultrasound and ionic liquid-enhanced extractive desulfurization of diesel
Authors: Zuraiqi Karma , Nancarrow Paul , Ahmed Hussain
Published: June 2018

The current desulfurization technology, hydrodesulfurization (HDS), is energy intensive, uses large quantities of hydrogen, and is ineffective at removing some sulfur compounds. Ionic liquids have been recently shown to perform well as extraction solvents for the removal of sulfur from diesel. However, a major limitation towards their industrial use is the low mass transfer rates that result from their relatively high viscosities. This study investigates the use of ultrasound to overcome this problem. The ionic liquid, 1-ethyl-3-methylimidazolium acetate ([C2mim][CH3COO]), was used to desulfurize model diesel consisting of dibenzothiophene in hexadecane, in the absence and presence of ultrasound. It was found that sonification can greatly enhance the rate of mass transfer of DBT from diesel to the IL, resulting in a 57% sulfur removal for a 75% decrease in extraction time for batch studies, which results in a reduction in the number of equilibrium stages necessary for a continuous extraction process.
Evaluation of Polymer Alternating Waterflooding in Multilayered Heterogeneous Waterflooded Reservoir
Authors: Tuncharoen Warut , Srisuriyachai Falan
Published: June 2018

Polymer flooding is widely implemented to improve oil recovery since polymer can increase sweep efficiency and smoothen heterogeneous reservoir profile. However, polymer solution is somewhat difficult to be injected due to high viscosity and thus, water slug is recommended to be injected before and during polymer injection in order to increase an ease of injecting this viscous fluid into the wellbore. In this study, numerical simulation is performed to determine the most appropriate operating parameters to maximize oil recovery. The results show that pre-flushed water should be injected until water breakthrough while alternating water slug size should be as low as 5% of polymer slug size. Concentration for each polymer slugs should be kept constant and recommended number of alternative cycles is 2. Combining these operating parameters altogether contributes to oil recovery of 53.69% whereas single-slug polymer flooding provides only 53.04% which is equivalent to 8,000 STB of oil gain.
Das Böse und die Wahrheit der Tat – Der Gutachter begegnet
dem Täter
Authors: Kröber Hans-Ludwig
Published: June 2018

Und bewahre uns vor dem Bösen… Das Böse löst Angst aus, seit Kindertagen. Lange
bevor wir es halbwegs definieren können, wissen wir, was wirklich böse ist. Wir
versuchen, uns von dem Bösen fernzuhalten, und auch selbst bösen Versuchungen zu
widerstehen. Aber dann haben wir beruflich, als Psychiater, Psychotherapeuten,
Sozialarbeiter, Rechtsanwalt oder auch Pfarrer sehr direkt zu tun mit Menschen,
die Böses getan haben, die vielleicht auch künftig Böses tun werden. Was tun?
Intimer Umgang mit dem Bösen?
Das Böse in der Philosophie
Authors: Kupke Christian
Published: June 2018

Gibt es eine Renaissance des Bösen? In der Kulturtheorie wird seit der Debatte um
den Islamismus wieder verstärkt über das Böse im religiös-theologischen Kontext
gesprochen. In der forensischen Psychiatrie hat das Thema durch Amoktaten wieder
an Bedeutung gewonnen. In der Politik wird darüber v. a. im Zusammenhang mit
dschihadistischer und rechtsextremer Gewalt diskutiert. Aus philosophischer
Sicht wäre es jedoch verkürzt, sich auf solche Kontexte zu beschränken.
Das Böse in der Religion – Eine psychotherapeutische
Perspektive
Authors: Baumann Klaus
Published: June 2018

Religionen und Religiosität von Patienten können sehr ambivalent erscheinen – als
gut und förderlich oder als lebensfeindlich und damit „böse“. Welche Rolle und
Deutung erfährt das Böse in seiner zerstörerischen Vielfalt in den Religionen?
Was braucht es, damit sie therapeutischen Wert gegen zerstörerische
Psychodynamiken entfalten, evtl. auch ohne religiöse Voraussetzungen? Der
Beitrag will zu einer differenzierten professionellen Perspektive anregen.