scholarly journals Geometrical form assessment of a CFD based breathing thermal manikins, designed by simplified polygonal shapes

2019 ◽  
Vol 85 ◽  
pp. 02002
Author(s):  
Martin Ivanov ◽  
Sergey Mijorski
Keyword(s):  
Flow Characteristics ◽  
Temperature Fields ◽  
Geometrical Shape ◽  
Thermal Plume ◽  
Flow Acceleration ◽  
Geometrical Shapes ◽  
Geometrical Form ◽  
The Difference ◽  
High Degree ◽  
Positive Effect

The presented paper focuses on a CFD based analyses of the complexity in the geometrical shape of the breathing thermal manikins, associated with their main functionalities. Both impacts of the external manikin’s form were studied – over the velocity and over the temperature fields in the thermal plume zone above the head. Three different geometrical shapes are analysed – a physiologically identified (called Humanoid Manikin) and two other shapes, designed to match the overall 95th percentile of the anthropometric size of the standard person (called Polygonal Manikins). The first model represents a comprehensive multifaceted figure of a manikin with high degree of physiological identity with a female human being. The second and third one, are simplified, but still with anatomically realistic component forms, accurately representing the anthropometric size of a standard person. The difference between them is in the presence of additional flow optimization collars in the third model. The numerical results demonstrate the clear impact of the manikins’ geometrical characteristics over the simulated breathing and convective flows. The optimization with the proposed collars had a positive effect over the resulted flow acceleration at top head and chest zones. However, the improvement of the flow characteristics was observed for two of the simulated three breathing phases and further shape optimization is required.

P-Removal in Completely Mixed Systems

1985 ◽  
Vol 17 (11-12) ◽  
pp. 325-326 ◽  
Author(s):  
H J. G. W. Donker ◽  
P. Opic ◽  
H. P. de Vries
Keyword(s):  
Mixed System ◽  
Domestic Waste ◽  
Recirculation Flow ◽  
Start Up ◽  
Significant Difference ◽  
Aerobic Reactor ◽  
The Difference ◽  
Positive Effect ◽  
Mixed Systems ◽  
P Removal

Ca. 60 % of the Dutch activated sludge plants consist of completely mixed systems, experiments have been carried out in completely mixed pilot plants to study the biological P-removal. The research was carried out in two pilot plants. The pilot plants consisted of: anaerobic reactor, anoxic reactor, aerobic reactor and a clarifier. All the reactors were completely mixed. Both plants were fed with settled domestic waste water at a sludge loading of 400 and 250 g COD/kg sludge.day respectively. The results are given below:sludge loading (g COD/kg sludge.day)400400250ratio Anaerobic : Anoxic : Aerobic1: 1:2,71:1:4,11:1:2,7P-removal (%)802875N-removal (%)505065COD-removal (%)858585 It has been shown that there is no significant difference between the results at the two different sludge loadings. Remarkable is the difference between the ratio 1:1:2,7 in combination with the internal recirculation flow anoxic-anaerobic of 160 % and the ratio 1:1:4,1 with a recirculation flow of 30 %. During the start-up at a sludge loading of 250 g COD/kg sludge.day and an internal recirculation flow of 30 %, bulking sludge developed almost immediately. The Premoval was completely disturbed. Increasing the internal recirculation flow to 160% had a positive effect on settling properties and P-removal. This investigation has pointed out that a completely mixed system is suitable for biological P-removal, without negatively affecting the nitrification. Important factors in the process are the ratio anaerobic:anoxic:aerobic and the recirculation flows.

scholarly journals Rural Financial Development Impacts on Agricultural Technology Innovation: Evidence from China

2021 ◽  
Vol 18 (3) ◽  
pp. 1110
Author(s):  
Yuyu Liu ◽  
Duan Ji ◽  
Lin Zhang ◽  
Jingjing An ◽  
Wenyan Sun
Keyword(s):  
Economic Development ◽  
Financial Development ◽  
Agricultural Development ◽  
Technology Innovation ◽  
Agricultural Technology ◽  
Rural Finance ◽  
Rural Economic Development ◽  
High Degree ◽  
The Impact ◽  
Positive Effect

Agricultural technology innovation is key for improving productivity, sustainability, and resilience in food production and agriculture to contribute to public health. Using panel data of 31 provinces in China from 2003 to 2015, this study examines the impact of rural financial development on agricultural technology innovation from the perspective of rural financial scale and rural finance efficiency. Furthermore, it examines how the effects of rural financial development vary in regions with different levels of marketization and economic development. The empirical results show that the development of rural finance has a significant and positive effect on the level of agricultural technology innovation. Rural finance efficiency has a significantly positive effect on innovation in regions with a low degree of marketization, while the rural financial scale has a significantly positive effect on technological innovation in regions with a high degree of marketization. Further analysis showed that improving the level of agricultural technology innovation is conducive to rural economic development. This study provides new insights into the effects of rural financial development on sustainable agricultural development from the perspective of agricultural technology innovation.

Numerical Simulation of Temperature Field on Different Surface Structure of Bicycle Brake Pairs

2014 ◽  
Vol 697 ◽  
pp. 235-238
Author(s):  
Gang Wu ◽  
Can Chao Huang ◽  
Hong Ling Qin ◽  
Chun Hua Zhao
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Surface Structure ◽  
Surface Structures ◽  
Temperature Fields ◽  
Transfer Model ◽  
Pair Model ◽  
Layer Composite ◽  
Positive Effect ◽  
Heat Loads

Using the basic principle of heat transfer, tribology and numerical simulation, a two-dimensional heat transfer model of the three-layer composite brake pair materials were established. The temperature fields of brake pairs during the process of friction were analyzed. Applied given heat loads at different time node on the brake pair model, the temperatures of different bicycle brake pairs were compared and analyzed. Results show that the improved surface structures of brake pair have positive effect on decreasing the temperature of contact areas than that of ordinary surface structure.

Gebruiksaspecten van het uitroeppartikel wat in het Nederlands en Fries

2020 ◽  
Vol 136 (4) ◽  
pp. 189-209
Author(s):  
Henk Wolf
Keyword(s):  
The Core ◽  
The Difference ◽  
Lexical Phrase ◽  
High Degree ◽  
Lexical Phrases

Abstract Both Dutch and (West) Frisian make use of the exclamative particle wat (‘how’), that adds an element of surprise about a high degree of something to the semantics of the sentence. In this paper I will first show the similarities between the use of the particle in the two languages. I will demonstrate that, in Dutch, its use is largely confined to constructions that are semantically scalable, whereas in Frisian this restriction is far less strict. I will explain the difference by showing that Dutch wat is a syntactic amplifier of lexical phrases, whereas Frisian wat has developed into a pragmatic amplifier of the core predicate. I will try to account for that difference by showing how homophonous words absent in Dutch are likely to have influenced the use of Frisian wat, and how Dutch prosody strengthens the connection between wat and the amplified lexical phrase, whereas Frisian prosody weakens it. Finally, I will show that the system described as ‘Frisian’ is occasionally found in varieties of Dutch too

About Determing the Microhardness of Composite Coatings

2021 ◽  
Vol 1037 ◽  
pp. 486-493
Author(s):  
Sergey Y. Zhachkin ◽  
Anatoly I. Zavrazhnov ◽  
Nikita A. Penkov ◽  
George V. Kudryavtsev ◽  
Paul V. Tsisarenko
Keyword(s):  
Composite Coating ◽  
Mechanical Treatment ◽  
Composite Coatings ◽  
Operational Parameters ◽  
Deposition Parameters ◽  
Cylinder Liners ◽  
High Degree ◽  
Applied Coating ◽  
Positive Effect ◽  
Selection Of

One of the fundamental tasks in restoring the operability of cylinder liners is the application of a composite coating with a predetermined microhardness value. The authors have developed a technology for applying composite coatings based on iron on cylindrical surfaces, which makes it possible to vary the physical, mechanical and operational parameters of the formed iron-containing coating due to the planned selection of the deposition parameters. This eliminates the need for mechanical treatment of the applied coating, which is the reason for the high degree of rejection parts that undergo the iron-on operation. Contact interaction of the working tool with the formed layer of the composite coating has a positive effect on the value of its roughness.

CARNIVAL POLITICAL TECHNOLOGIES: MASKS OF LOCAL AUTHORITIES IN MODERN RUSSIA

2021 ◽  
Vol 16 (3) ◽  
pp. 53-68
Author(s):  
A.V. SKIPERSKIKH ◽  
Keyword(s):  
Political Process ◽  
Political Class ◽  
Current State ◽  
Cultural Specificity ◽  
The Russian Federation ◽  
The Government ◽  
Social Organism ◽  
High Degree ◽  
Game Forms ◽  
Positive Effect

The purpose of the research is to present how the carnival element in the regional policy is associated with the legitimating of power. Also made of the current state of the regional political process in some constituent entities of the Russian Federation, characterized by a high degree of carnivalization. As a result, the importance of the practices of the regional elite, resorting to game forms of their own positioning. The legitimacy of the regional power to depend on festive discourse. A routine political process in the constituent entities of the Russia does not evoke public emotions that have a positive effect on the legitimation of power. The demand for the politics of spectacle is also present in municipal political practices in a very dangerous epoch of COVID-19. A social organism that needs emotions, as well as control, does not experience serious transformations. In society penchant for spectacle, as well as the political class in the production of carnival events, there are deep historical roots, as well as the cultural specificity of a particular region. The points out that in the regional political process one can increasingly see accents on festivals. So, the government solves two important problems: the first one is a public request for a show, it is resolved in conditions of a rather unpleasant and unpromising accumulation of negative for the authorities due to the deterioration of the socio-economic situation in general, the second one is the production of the play solves the issues of legitimation regional and municipal authorities.

Numerical Study on Flow Characteristics in High Multi-Stage Pressure Reducing Valve

2017 ◽  
Author(s):  
Fu-qiang Chen ◽  
Zhi-xin Gao ◽  
Jin-yuan Qian ◽  
Zhi-jiang Jin
Keyword(s):  
Energy Consumption ◽  
Numerical Study ◽  
Research Work ◽  
Flow Characteristics ◽  
Temperature Fields ◽  
Turbulent Dissipation ◽  
Technological Support ◽  
Multi Stage ◽  
Valve Opening ◽  
Pressure Reducing Valve

In this paper, a new high multi-stage pressure reducing valve (HMSPRV) is proposed. The main advantages include reducing noise and vibration, reducing energy consumption and dealing with complex conditions. As a new high pressure reducing valve, its flow characteristics need to be investigated. For that the valve opening has a great effect on steam flow, pressure reduction and energy consumption, thus different valve openings are taken as the research points to investigate the flow characteristics. The analysis is conducted from four aspects: pressure, velocity, temperature fields and energy consumption. The results show that valve opening has a great effect on flow characteristics. No matter for pressure, velocity or temperature field, the changing gradient mainly reflects at those throttling components for all valve openings. For energy consumption, in the study of turbulent dissipation rate, it can be found that the larger of valve opening, the larger of energy consumption. It can be concluded that the new high multi-stage pressure reducing valve works well under complex conditions. This study can provide technological support for achieving pressure regulation, and benefit the further research work on energy saving and multi-stage design of pressure reducing devices.

Experimental and Numerical Study of Honeycomb Tip on Suppressing Tip Leakage Flow in Turbine Cascade

2017 ◽  
Author(s):  
Yunfeng Fu ◽  
Fu Chen ◽  
Huaping Liu ◽  
Yanping Song
Keyword(s):  
Numerical Study ◽  
Flow Characteristics ◽  
Leakage Flow ◽  
Exit Section ◽  
Turbine Cascade ◽  
Tip Leakage Flow ◽  
Physical Processes ◽  
Tip Leakage ◽  
Gap Height ◽  
Positive Effect

In this paper, the effect of a novel honeycomb tip on suppressing tip leakage flow in a highly-loaded turbine cascade has been experimentally and numerically studied. The research focuses on the mechanisms of honeycomb tip on suppressing tip leakage flow and affecting the secondary flow in the cascade, as well as the influences of different clearance heights on leakage flow characteristics. In addition, two kinds of local honeycomb tip structures are pro-posed to explore the positive effect on suppressing leakage flow in simpler tip honeycomb structures. Based on the experimental and numerical results, the physical processes of tip leakage flow and its interaction with main flow are analyzed, the following conclusions can be obtained. Honeycomb tip rolls up a number of small vortices and radial jets in regular hexagonal honeycomb cavities, increasing the flow resistance in the clearance and reducing the velocity of leakage flow. As a result, the structure of honeycomb tip not only suppresses the leakage flow effectively, but also has positive effect on reducing the associated losses in cascade by reducing the strength of leakage vortex. Compare to the flat tip cascade at 1%H gap height, the relative leakage flow in honeycomb tip cascade reduces from 3.05% to 2.73%, and the loss at exit section is also decreased by 10.63%. With the increase of the gap height, the tip leakage flow and loss have variations of direct proportion with it, but their growth rates in the honeycomb tip cascade are smaller. Consider the abradable property of the honeycomb seal, a smaller gap height is allowed in the cascade with honeycomb tip, and that means honeycomb tip has better effect on suppressing leakage flow. Two various local honeycomb tip structures has also been discussed. It shows that local raised honeycomb tip has better suppressing leakage flow effect than honeycomb tip, while local concave honeycomb tip has no more effect than honeycomb tip. Compare to flat tip cascade, the leakage flow in honeycomb tip cascade, local concave tip cascade and local raised honeycomb tip cascade decrease by nearly 17.33%, 15.51% and 30.86% respectively, the losses at exit section is reduced by 13.38%, 12% and 28.17% respectively.

scholarly journals LA INSERCIÓN COMERCIAL DE CHINA EN LATINOAMÉRICA

2019 ◽  
Vol 78 (310) ◽  
pp. 137
Author(s):  
Jorge Alberto López Arévalo ◽  
Óscar Rodil Marzábal
Keyword(s):  
Costa Rica ◽  
Free Trade ◽  
Fixed Effects ◽  
Bilateral Trade ◽  
Free Trade Agreements ◽  
Trade Agreements ◽  
Trade Integration ◽  
Negative Effect ◽  
The Difference ◽  
Positive Effect

<p>Este trabajo estudia los intercambios bilaterales de China con México, Chile, Costa Rica y Perú desde la óptica del comercio intraindustrial durante 1995-2017. En particular, se analizan las diferencias en el patrón de inserción intraindustrial en un contexto marcado por la existencia (Chile, Costa Rica y Perú) o no (México) de acuerdos de libre comercio con China. El estudio se completa con un análisis econométrico (efectos fijos) de los determinantes del comercio intraindustrial. Los resultados muestran una inserción de bajo perfil intraindustrial, con la excepción de algunas partidas específicas relativas a productos eléctricos y de la industria automotriz. Por otro lado, se confirma el efecto positivo del tamaño de la economía, de la inversión extranjera directa y de la diferenciación de producto, así como negativo de la diferencia en el nivel de ingreso; mientras que existe una indefinición en el papel de los acuerdos de libre comercio con China.<br /><br /></p><p>THE TRADE INTEGRATION OF CHINA IN LATIN AMERICA</p><p> </p><p><strong>ABSTRACT</strong><br />This paper studies China’s bilateral trade with Mexico, Chile, Costa Rica and Peru from the perspective of intra-industrial trade during 1995-2017. In particular, the differences in the pattern of intra-industrial insertion are analyzed in a context characterized by the existence (Chile, Costa Rica and Peru) or not (Mexico) of free trade agreements with China. An econometric analysis (fixed effects) of the determinants of intra-industrial trade completes the study. The results show a low intra-industrial profile, except for some specific items related to electrical products and the automotive industry. The positive effect of the size of the economy, foreign direct investment and product differentiation is also confirmed, as well as the negative effect of the difference in income level. However, there is an undefined role for free trade agreements with China.</p>

scholarly journals Amplitude response of a telemetered seismic system from seismometers to digital acquisition system

1995 ◽  
Vol 38 (1) ◽  
Author(s):  
R. Di Giovambattista ◽  
S. Barba ◽  
A. Marchetti
Keyword(s):  
Digital Signals ◽  
Amplitude Response ◽  
Automatic Mode ◽  
Steady State Method ◽  
Sinusoidal Current ◽  
Fully Automatic ◽  
The Difference ◽  
High Degree ◽  
Seismic System

Automated amplitude response of the complete seismometer, telemetry and recording system js obtaiued trom sinusoidal inputs to the calibration coil. Custom-built software was designed to perform fully automatic cali- bration analyses of the digital signals. In this paper we describe the signals used for calibration and interactive and batch procedures designed to obtain calibration functions in automatic mode. By using a steady-state method we reach a high degree of accuracy in the determination of both the frequency and amplitude of the \ignal. The only parameters required by this procedure are the seismometer mass, the calibration-coil constant and the intensity of the current injected into the calibration coil. This procedure is applicable to telemetered seismic systems and represents an optimization of the processing time. The software was designed to requjre no modification" jf the device used to generate the sinusoidal current should change. In particular, it is possi- ble to changc the number of monotrequcncy packages transmitted to the calibration coil with the on]y restric- tion that the difference between the frequency of two consecutjve packages be greater than 5%; for these rea- sons the procedure is expected to be usefu] for the seismological community. The paper inc]udes a generaI de- scription of thc designing criteria, and of the hardware and software architecture, as well as an account of thc system's performancc during a two year period of operation.

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