Influence Of Different Locations Research Articles

Aeroacoustic source localization using the microphone array method with application to wind turbine noise

The deconvolution DAMAS algorithm can effectively eliminate the misconceptions in the usually-used beamforming localization algorithm, allowing for a more accurate calculation of the source location as well as the intensity. When solving a linear system of equations, the DAMAS algorithm takes into account the mutual influence of different locations, reducing or even eliminating sidelobes and producing more accurate results. This work first introduces the principles of the DAMAS algorithm. Then it applies both the conventional beamforming algorithm and the DAMAS algorithm to simulate the localization of a single-frequency source from a 1.5 MW wind turbine, a complex line source with the text “UCAS” and a line source downstream of an airfoil trailing edge. Finally, the work presents experimental localization results of the source of a 1.5 MW wind turbine using both the conventional beamforming algorithm and the DAMAS algorithm.

INFLUENCE OF SITES ON THE PHYSICAL AND MECHANICAL PROPERTIES OF NATIVE TROPICAL WOODS

The Amazon rainforest displays wide ecological diversity, reflected in its wood variation. The study evaluated the influence of different locations on the properties of wood from native tropical species extracted from the Brazilian Amazon. The most frequent species in the locations were selected, and a total of 104 trees were extracted. The logs were sawed breakdown to make beams (50 × 110 × 2,000 mm). The wood density and mechanical resistance of these samples were determined. The wood density ranged of 0.25-1.00 g/cm3, modulus of elasticity and rupture in static bending ranged of 5,982-19,025 MPa and 35-204 MPa, respectively. For compressive strength parallel to the grain, the range was 24-111 MPa; the strength of wood compressed parallel was 20-245 MPa, and the shear strength was 50-245 MPa. The study detected differences in the physical and mechanical properties of the woods regarding the origin of the sites (Amazonas-Pará/Brazil), with the modulus of elasticity and the wood density showing the greatest variations.

Can financial agglomeration curb carbon emissions reduction from agricultural sector in China? Analyzing the role of industrial structure and digital finance

As China enters the process of agricultural modernization, the problem of carbon emissions from agricultural sectors has become increasingly prominent, and the government and academia urgently need to take action. In this context, this study extends the literature through a new perspective of China's financial agglomeration construction that examines the actual role of financial agglomeration on agricultural carbon emissions reduction by using two-way fixed effect model and threshold effect model based on the panel data of 30 provinces in China from 2011 to 2019. Data statistics show that China has formed a multi-center development pattern with Beijing-Tianjin-Hebei, Yangtze River Delta, Guangdong-Hong Kong-Macao as highly financial agglomeration under the influence of different locations, factor endowments and development foundations. Further empirical model estimates reveal the following main findings. Firstly, the effects of financial agglomeration on total agricultural carbon intensity (TACI), agricultural greenhouse gas carbon intensity (AGCI), agricultural energy carbon emission intensity (AECI), and agricultural input factors carbon intensity (ASCI) show an inverted U-shaped curve that from irritating to inhibiting. That is, financial agglomeration is conducive to slowing down agricultural carbon emissions. Secondly, financial agglomeration has a significant inhibitory effect on TACI, AGCI, AECI and ASCI in Beijing and Shanghai. Thirdly, when the industrial structure is more reasonable or the digital finance is more developed, the effect of financial agglomeration on reducing agricultural carbon emissions is stronger. Based on the current research results, promoting the construction of financial agglomeration is an effective way to promote agricultural carbon emissions reduction, and it is suggested that the government design effective systems and policies to slow down the carbon emissions in the agricultural sector.

Influence of different air distribution on ventilation effectiveness in negative pressure hospital wards

Hospital ward is one of non-negligible potential places to occur cross-infection among patients and health workers. Air-borne transmission was regarded as the main infection route of the SARS-CoV-2. Preventing the air-borne transmission should be a significant measure, which could effectively mitigate the risk of the virus infection. Based on those consideration, in this study, the influence of different types of air distribution on ventilation effectiveness was modeled through Computational Fluid Dynamics (CFD) simulations. Several typical negative pressure wards same as the ward in Wuhan Thunder God Mountain hospital and conformed to the Chinese National Health Commission (NHC) guidelines were modelled. We simulated the influence of different locations of air supply inlets, analysed the influence of the buffer door and compared the contaminant concentration on different entry route for health workers. The results show that the air distribution required by NHC guidelines could retain a directional airflow from the bed-zone to the toilet, which also has a better accessibility of supply air, and health workers are safer to avoid standing closed to the air exhaust outlet in the downstream area of pollutants during ward rounds.

Finite element study of stem cells under fluid flow for mechanoregulation toward osteochondral cells

Investigating the effects of mechanical stimuli on stem cells under in vitro and in vivo conditions is a very important issue to reach better control on cellular responses like growth, proliferation, and differentiation. In this regard, studying the effects of scaffold geometry, steady, and transient fluid flow, as well as influence of different locations of the cells lodged on the scaffold on effective mechanical stimulations of the stem cells are of the main goals of this study. For this purpose, collagen-based scaffolds and implicit surfaces of the pore architecture was used. In this study, computational fluid dynamics and fluid-structure interaction method was used for the computational simulation. The results showed that the scaffold microstructure and the pore architecture had an essential effect on accessibility of the fluid to different portions of the scaffold. This leads to the optimization of shear stress and hydrodynamic pressure in different surfaces of the scaffold for better transportation of oxygen and growth factors as well as for optimized mechanoregulative responses of cell–scaffold interactions. Furthermore, the results indicated that the HP scaffold provides more optimizer surfaces to culture stem cells rather than Gyroid and IWP scaffolds. The results of exerting oscillatory fluid flow into the HP scaffold showed that the whole surface of the HP scaffold expose to the shear stress between 0.1 and 40 mPa and hydrodynamics factors on the scaffold was uniform. The results of this study could be used as an aid for experimentalists to choose optimist fluid flow conditions and suitable situation for cell culture.

Contaminant Removal from Virtual Operation Room

Most bacterial contaminants found in operation rooms come from patient’s exhale or from wounds after surgery that make colony forming units. Thus, yearly, a lot people suffer from infections acquired during surgical procedures. Removing pollutants from operation room by investigating the influence of different locations and types of entry and exit grills is the subject of the present work. Equations of fluid flow including the continuity, momentum, energy equations and species equation have been numerically solved by using the FLUENT ANSYS v.14 for virtual symmetric operation room taken in this paper. Turbulent flow of mixture material species is applied in the model of operation room. Standard K-epsilon was used for simulating turbulent flow pattern. The present study aims to find a proper arrangement of inlet and exhaust locations to reduce the unfavorable factors in operation room such us, contamination, humidity, temperature and also air velocity. These factors were achieved according to modification in inlet and exhaust grills arrangement and then simulated through FLUENT software program. Six different arrangements of supply and exhaust were studied to determine case of best health and comfort demands. Case no 5, using local exhaust ventilation, shows good improvement in removing contaminants. However, case no 6 which uses both local exhaust ventilation and like air curtain air supply, shows the optimum removal of contaminants, because it shows lower contamination mass fraction. Meanwhile, the worst contaminant removal were in case 2 and case 1, where source of contaminant exists in low movement zone (dead zones) or region of separation of streamlines. The results showed, using both local exhaust ventilation and like air curtain air supply as in case (6) maintains an average temperature of 21.3 °C, the least amount of particles mass fraction of contaminants 6.36E-08 and moisture content of 0.009.

Seismic exploration in tunneling using full waveform inversion with a frequency domain model

AbstractWith the knowledge of the geology in front of a tunnel, the excavation process can be optimized to avoid damage at the tunnel boring machine and settlements on the surface. Therefore, dwell times can be decreased and additional expenses can be avoided. Transmitted seismic waves will be spread, reflected and refracted due to geological changes. By utilizing geophones, the seismic waves will be captured and information about the geological structure in front of the tunnel can be extracted from the measured seismograms using e.g. the concept of full waveform inversion. A frequency domain model has been employed to demonstrate the potential of full waveform inversion for seismic reconnaissance in a tunnel environment. The success of the inversion procedure depends strongly on the positions of the utilized sender and receiver stations, the chosen initial material parameter distribution, and on the selected frequency groups for the inversion. Further challenges are an accurate representation of the reflecting surfaces and the application of absorbing borders to oppress reflections from the artificial boundaries, which delimit the analyzed domain. The results of the performed full waveform inversion for synthetic models of a 3D tunnel configuration with different disturbances ahead of the front tunnel face will be discussed. Additionally, the influence of different locations of the sender and receiver stations will be analyzed.

不同脑白质损伤部位对老年轻度认知障碍的影响 Influence of Different Location of White Matter Lesion on Mild Cognitive Impairment in Senile Patients

不同脑白质损伤部位对老年轻度认知障碍的影响 Influence of Different Location of White Matter Lesion on Mild Cognitive Impairment in Senile Patients

The influence of different locations on copper corrosion with different external electric fields under a chloride-containing thin electrolyte layer

ABSTRACTThe influence of different locations on copper corrosion with different external electric fields under a chloride-containing thin electrolyte layer was studied using polarisation curve measurement and surface analysis techniques. The results indicated that, under an external direct current electric field, the anodic current densities near the positive plate were smaller than that near the negative plate, while the cathodic current densities near the positive plate were larger than that near the negative plate. However, at different locations in an external alternating current electric field, the anodic current densities were little change, while the cathodic current densities were obviously different.

The influence of different locations of sputter guns on the morphological and structural properties of Cu–In–Ga precursors and Cu(In,Ga)Se2 thin films

The influence of two different locations of sputter guns on the morphological and structural properties of Cu–In–Ga precursors and Cu(In,Ga)Se2 (CIGS) thin films was investigated. All the precursors contained cauliflower-like nodules, whereas smaller subnodules were observed on the background. All the precursors revealed apparent three-layered structures, and voids were observed at the CIGS/SLG interface of Sets 1 and 2 films rather than Set 3 film. EDS results indicated that all CIGS thin films were Cu-deficient. Based on the grazing incidence X-ray diffraction (GIXRD) patterns, as-selenized films showed peaks corresponding to the chalcopyrite-type CIGS structure. Depth-resolved Raman spectra showed the formation of a dominant CIGS phase inside the films for all the as-selenized samples investigated, and of an ordered vacancy compound (OVC) phase like Cu(In,Ga)3Se5 or Cu(In,Ga)2Se3.5 at the surface and/or CIGS/SLG interface region of Sets 2 and 3 films. No evidence was obtained on the presence of an OVC phase in Set 1 CIGS film, which may be speculated that long-time annealing is contributed to suppress the growth of OVC phases. The results of the present work suggest that the metallic precursors deposited with the upright-location sputter gun might be more appropriate to prepare CIGS thin films than those sputtered with the titled-location gun.

Effect on wireless power transmission with different layout of left-handed materials

In order to improve the efficiency and to increase the distance of the wireless power transmission system, we studied the application of the left-handed materials on it. From the point of view of evanescent waves as well as the negative refraction effect, verified left-handed materials’ ability to improve efficiency. The contribution of the four layouts named single flatbed, dual flatbeds, full bracketing and semi-bracketing model were compared and analyzed. Furthermore, the influence of different location and thickness was also discussed, and their results were explained theoretically. Finally, we proposed the superiority of the dual flatbeds model, for its highest efficiency improvement, easy production and convenience.

Sensory stimulation (massage) reduces blood pressure in unanaesthetized rats

The objective of this study was to investigate how sensory stimulation by massage-like stroking influences blood pressure and heart rate in conscious rats. Also, the influence of different locations and durations of the stimulation were assessed. For this purpose, the ventral side of the abdomen or the dorsal side of the back was manually stroked at a speed of approximately 20 cm/s, with a frequency of 0.67 Hz and at an estimated pressure of 100 mm H 2O. During the treatment, the rats were held across the scapula and the neck region. Blood pressure and heart rate were measured with the cuff technique before treatment and repeatedly during the post-stimulatory period. Massage-like stroking for 5 min of the abdominal area produced a maximum decrease of approximately 20 mm Hg in blood pressure and 60 beats/min in heart rate. This reduction remained significant at 3 and 4 h after stimulation, respectively. Stimulation of the abdominal area for 2 min produced a less pronounced decrease in blood pressure as compared to the 5-min stroking. Stroking of the back resulted in a short-lasting blood pressure increase that gradually returned to the baseline level within the post-stimulatory observation time. Control animals that were handled in the same way as the experimental animals except for the stroking showed an increase of approximately 20 mm Hg in blood pressure and 60 beats/min for about 1 h after the cessation of the handling. The responses of the blood pressure and heart rate to both abdominal and back massage were significantly inhibited as compared to the control animals. These results suggest that massage-like stroking of the skin produces an inhibitory effect on the cardiovascular excitatory responses in rats. Especially, the results of the present study demonstrate that massage-like stroking of the abdomen reduces both blood pressure and heart rate below the pre-stimulus baseline levels.

Finite element simulation of the hydrothermal behaviour of an artificial aquifer for seasonal energy storage

A mathematical-numerical procedure is being used to calculate the time marching temperature field in the Artificial Aquifer for thermal energy storage of the Stuttgart University. The procedure is based on the Finite Element Method and is able to simulate the behaviour of the aquifer during charging and discharging, by exchanging water directly. When the aquifers' geometry was determined, the numerical model was used to evaluate the influence of different locations of the water inlet and outlet facilities as well as possible layering of the aquifer on the expected flow and temperature field.