scholarly journals Model Investigations of Scouring at the Hričov Weir Using Short-Range Photogrammetry

2021 ◽  
Vol 1203 (2) ◽  
pp. 022101
Author(s):  
Ján Rumann ◽  
Martin Pavúček ◽  
Peter Dušička
Keyword(s):  
Short Range ◽  
Water Structure ◽  
Contactless Method ◽  
Scaled Model ◽  
Operational Conditions ◽  
Stilling Basin ◽  
Operation Conditions ◽  
Different Types ◽  
Stilling Basins ◽  
Very High

Abstract Stilling basins are commonly used to efficiently dissipate energy of flow at weirs. Different types of stilling basins are used at weirs due to different conditions – hydraulic, operational, constructional. At the Hričov water structure a short stilling basin has been built. Its operation over the years showed that it does not dissipate the energy of the flowing water sufficiently, which causes intense scouring in the riverbed downstream. To partially deal with this problem and to protect the riverbed from scours, a rockfill embankment supported with a steel construction was constructed adjacent to the stilling basin’s toe. Despite this riverbed fortification, scours are being created in the riverbed and even in the fortification itself for different cases of operation conditions of the weir. A hydraulic research on a scaled model of the weir was used to investigate the problem and to propose a permanent solution significantly improving the scouring downstream the weir. The proposed fortification of the riverbed downstream the weir was tested at different operational conditions, which simulated extreme situations at the weir. To assess the effects of the investigated fortification, the simulations were performed for the weir without and with the fortification. After each simulation, the deformations in the riverbed (scours) were measured and evaluated. For measuring the riverbed deformations on the model, the method of short-range photogrammetry was used as a very effective and contactless method. This method allowed to examine the investigated area with a very high accuracy and speed. Digital models of the riverbed deformations created after each simulation on the hydraulic model were used to determine the locations and sizes of the deepest scours. Final assessment of the results showed the improvement in the reduction of scouring by the proposed fortification by almost 50% in the size of the scours. The investigations and the results are described in this paper.

Estimation of Energy Saving for Melting Process on Sewage Sludge

1991 ◽  
Vol 23 (10-12) ◽  
pp. 2011-2018 ◽  
Author(s):  
T. Murakami ◽  
K. Sasabe ◽  
K. Sasaki ◽  
T. Kawashima
Keyword(s):  
Sewage Sludge ◽  
Moisture Content ◽  
Energy Saving ◽  
Fuel Consumption ◽  
Melting Process ◽  
System Operation ◽  
Operational Conditions ◽  
Volatile Solids ◽  
Cake Moisture ◽  
Very High

The possible volume reduction and stabilization of the sewage sludge associated with the melting process are expected to be greater than with the incineration process. In addition, melted slag can be utilized. However, since the melting process requires a very high temperature to melt inorganics (ash) in the sludge, the technologies to minimize energy consumption, to establish system operation and to prolong durability of facilities should be developed. This paper discusses the auxiliary fuel consumption as follows.(1)Preparation of a model that provides the auxiliary fuel consumption of the melting system on the basis of the mass and heat balances.(2)Evaluation of the auxiliary fuel consumption in the above model using the cake moisture content, the volatile solids of the cake, the dried cake moisture content and the melting temperature as parameters.(3)Examination of the operational conditions for an energy saving melting system based on the results of (1) and (2) above.

scholarly journals Germanium Nanowires as Sensing Devices: Modelization of Electrical Properties

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 507
Author(s):  
Luca Seravalli ◽  
Claudio Ferrari ◽  
Matteo Bosi
Keyword(s):  
Charge Transfer ◽  
Electrical Properties ◽  
Surface Charges ◽  
Molecular Sensing ◽  
Germanium Nanowires ◽  
Physical Mechanisms ◽  
Additional Doping ◽  
Different Types ◽  
N Doping ◽  
Very High

In this paper, we model the electrical properties of germanium nanowires with a particular focus on physical mechanisms of electrical molecular sensing. We use the Tibercad software to solve the drift-diffusion equations in 3D and we validate the model against experimental data, considering a p-doped nanowire with surface traps. We simulate three different types of interactions: (1) Passivation of surface traps; (2) Additional surface charges; (3) Charge transfer from molecules to nanowires. By analyzing simulated I–V characteristics, we observe that: (i) the largest change in current occurs with negative charges on the surfaces; (ii) charge transfer provides relevant current changes only for very high values of additional doping; (iii) for certain values of additional n-doping ambipolar currents could be obtained. The results of these simulations highlight the complexity of the molecular sensing mechanism in nanowires, that depends not only on the NW parameters but also on the properties of the molecules. We expect that these findings will be valuable to extend the knowledge of molecular sensing by germanium nanowires, a fundamental step to develop novel sensors based on these nanostructures.

Radiation Curable Polysiloxane: Synthesis to Applications

Soft Matter ◽  
2021 ◽  
Author(s):  
Selvan T. Muthamil ◽  
Titash Mondal
Keyword(s):  
Structural Features ◽  
Superior Performance ◽  
Operational Conditions ◽  
Different Types

Among the different types of specialty polymers, polysiloxane finds its position in the pyramid's apex in performance attributes. Unique structural features result in superior performance benefits over wide operational conditions....

Unsymmetrical phthalocyanines with cyclopalladated azo functions

2012 ◽  
Vol 16 (02) ◽  
pp. 192-199 ◽  
Author(s):  
H. Yasemin Yenilmez Akkurt ◽  
Ali ihsan Okur ◽  
Ahmet Gül
Keyword(s):  
Organic Solvents ◽  
Column Chromatography ◽  
Spectroscopic Analysis ◽  
Palladium Complex ◽  
Palladium Complexes ◽  
High Solubility ◽  
Synthetic Procedure ◽  
Different Types ◽  
New Compounds ◽  
Very High

In this study, a synthetic procedure for unsymmetrical metallophthalocyanines of the form M[Pc(AB3)], where A and B refer to two different types of peripheral functionality, has been developed and the new compounds have been converted to monomeric and dimeric palladium complexes. Asymmetrically substituted phthalocyanines were synthesized with the well-known statistical condensation method, by using two differently substituted precursors, namely 4-(2-ethoxyethoxy)-1-2-dicyanobenzene (1) and 4-{4-[Z/E]-phenylazo]-1-naphthyl}oxy-1,2-dicyanobenzene (2). Consequently, electron-donating 2-ethoxyethoxy groups and electron-withdrawing palladium complex are present in the same structure. Cyclopalladation was performed with [Pd(PhCN)2Cl2] to yield the bis-μ-chloro-bridged dimers and subsequently, the corresponding monomers were obtained by refluxing with three equivalents of potassium acetylacetonate. The resulting products were purified by column chromatography and characterized by several chemical and spectroscopic analysis methods. All compounds have very high solubility in organic solvents due to the presence of 2-ethoxyethoxy moiety.

scholarly journals Microgels and Nanoparticles: Where Micro and Nano Go Hand in Hand

2015 ◽  
Vol 229 (1-2) ◽  
Author(s):  
Beatriz H. Juarez ◽  
Luis M. Liz-Marzán
Keyword(s):  
Magnetic Nanoparticles ◽  
Optical Tweezers ◽  
Hybrid System ◽  
Inorganic Nanoparticles ◽  
Stimuli Responsive ◽  
Single Particles ◽  
Nanoscale Systems ◽  
Different Types ◽  
Potential Applications ◽  
Very High

AbstractThe integration of different types of materials in a single hybrid system allows the combination of multiple functionalities, which can even be used in conjunction with each other. This strategy has been exploited in nanoscale systems for the creation of so-called smart nanomaterials. Within this category, the combination of inorganic nanoparticles with stimuli-responsive microgels is of very high interest because of the wide variety of potential applications. We present here a short overview of this type of materials in which the nano- and micro-scales get nicely integrated, with a great potential to expand the range of technological applications. We focus mainly on the integration of metal nanoparticles, either by themselves or in combination with semiconductor and magnetic nanoparticles. Various examples of the synergic properties that can be obtained are described, as well as the possibility to extract useful information when optical tweezers are used to manipulate single particles. We expect that this review will stimulate additional research in this field.

scholarly journals CNN BASED DETECTION OF BUILDING ROOFS FROM HIGH RESOLUTION SATELLITE IMAGES

2020 ◽  
Vol XLII-3/W10 ◽  
pp. 187-192
Author(s):  
L. Hang ◽  
G. Y. Cai
Keyword(s):  
High Resolution ◽  
Residential Building ◽  
Training Image ◽  
Training Dataset ◽  
Classification Approach ◽  
Object Based ◽  
High Resolution Satellite Images ◽  
Different Types ◽  
Model Training ◽  
Very High

Abstract. The detection and reconstruction of building have attracted more attention in the community of remote sensing and computer vision. Light detection and ranging (LiDAR) has been proved to be a good way to extract building roofs, while we have to face the problem of data shortage for most of the time. In this paper, we tried to extract the building roofs from very high resolution (VHR) images of Chinese satellite Gaofen-2 by employing convolutional neural network (CNN). It has been proved that the CNN is of a higher capability of recognizing detailed features which may not be classified out by object-based classification approach. Several major steps are concerned in this study, such as generation of training dataset, model training, image segmentation and building roofs recognition. First, urban objects such as trees, roads, squares and buildings were classified based on random forest algorithm by an object-oriented classification approach, the building regions were separated from other classes at the aid of visually interpretation and correction; Next, different types of building roofs mainly categorized by color and size information were trained using the trained CNN. Finally, the industrial and residential building roofs have been recognized individually and the results have been validated individually. The assessment results prove effectiveness of the proposed method with approximately 91% and 88% of quality rates in detection industrial and residential building roofs, respectively. Which means that the CNN approach is prospecting in detecting buildings with a very higher accuracy.

scholarly journals State of the art olfactometers. Different types

2021 ◽  
Keyword(s):  
Human Beings ◽  
Pathological Conditions ◽  
New Concepts ◽  
Different Types ◽  
Clinical Diagnoses ◽  
Human Use ◽  
The Brain ◽  
Very High ◽  
Human Olfaction

The complexity of human olfaction is very high and the importance of being able to measure it directly, objectively and qualitatively has led experts to search for mechanisms that can be applied. Human beings use this sense, which is one of the oldest, to recognize danger and distinguish between pleasant and unpleasant odors. Smells are mixtures of molecules that, at different concentrations in the inhaled air, stimulate the olfactory area and are recognized at the brain level. Therefore, there is a coding and decoding system. Human olfactometer techniques use equipment designed to be able to measure its intensity and quality of volatile substances. If we are able to measure this sense, we will be able to know its variations and be able to make clinical diagnoses in normal and pathological conditions and diagnose the losses that occur in certain infectious, degenerative diseases, traumatic processes and other variants. For many years, systems have been developed that can measure subjective olfaction in humans, as well as objective forms, but it is also true that there is no equipment available that is fast, simple handling and that can be applied in daily clinical services. Aim of the Study Present the recent achievements in olfactometer technology; Elaborate the scientific articles about olfactometry published mainly in the last 10 years; To gather the information published in the last years in relation to the usefulness, existence in the market and purposes of equipment that can measure the odors, what we will call the Smell-o-meter or olfactometer for human use. Material and Methods: In the first part of this research we will gather most of the information existing so far in international bibliography, as well as the achievements and utilities obtained to date. Following, we will analyze all the new concepts related to smell-o-meters devices that exist on the market and assess the possibility, based on what has been done so far, to seek new practical systems for application in the medical field.

scholarly journals Glucose status in cerebrospinal fluid (CSF) in different meningitic children in a hospital in Chittagong, Bangladesh

2013 ◽  
Vol 6 (1-2) ◽  
pp. 41-49
Author(s):  
Sharmistha Mitra ◽  
Robiul Hasan Bhuiyan ◽  
Md Arifuzzaman ◽  
Mohammad Sayedul Islam ◽  
Mahmood A Chowdhury ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Glucose Level ◽  
Viral Meningitis ◽  
Pyogenic Meningitis ◽  
Detailed Medical History ◽  
Different Types ◽  
The Brain ◽  
Very High ◽  
Potential Tool ◽  
Glucose Status

Meningitis is referred to as an inflammatory process of the leptomeninges and cerebrospinal fluid (CSF) within the sub-arachnoid space of the brain. We have investigated glucose status in CSF in different types of meningitis together with detailed medical history in children. In addition, we have also carried out the detailed cytological and microbiological examinations. A total of 40 subjects were investigated. We observed that the glucose level was significantly decreased (<20 mg/dl) in 65%, moderately decreased (20-40 mg/dl) in 20% and mildly decreased (40-50mg/dl) in 15% of the patients in our study. Patients with Pyogenic meningitis had tremendously reduced glucose level (9.0 mg/dl) in their CSF whereas in viral meningitis the CSF glucose level is highly variable (10 to 65 mg/dl). Furthermore, 5 (12.5%) patients showed high lymphocyte counts and 34 (85%) patients showed high neutrophil counts. Interestingly, in Pyogenic meningitis, the neutrophil count was very high compared to that in viral meningitis. The present study clearly demonstrates that biochemical parameters such as glucose level in CSF might be a potential tool for detecting meningitis and as well as differentiation of the different types of meningitis. DOI: http://dx.doi.org/10.3329/cujbs.v6i1-2.17080 The Chittagong Univ. J. B. Sci.,Vol. 6(1&2):41-49, 2011

scholarly journals The analysis of flutter characteristics based on generalized parameters of eigen modes of vibrations

2021 ◽  
pp. 95-102
Author(s):  
K. I Barinova ◽  
A. V Dolgopolov ◽  
O. A Orlova ◽  
M. A Pronin
Keyword(s):  
Mathematical Model ◽  
High Speed ◽  
Dynamic Pressure ◽  
Mode Shapes ◽  
Scaled Model ◽  
Design Specifications ◽  
Operation Conditions ◽  
Flutter Analysis ◽  
Generalized Parameters ◽  
The Mathematical Model

Flutter numerical analysis of a dynamically scaled model (DSM) of a high aspect ratio wing was performed using experimentally obtained generalized parameters of eigen modes of vibrations. The DSM is made of polymer composite materials and is designed for aeroelastic studies in a high-speed wind tunnel. As a result of the analysis, safe operation conditions (flutter limits) of the DSM were determined. The input data to develop the flutter mathematical model are DSM modal test results, i.e. eigen frequencies, mode shapes, modal damping coefficients, and generalized masses obtained from the experiment. The known methods to determine generalized masses have experimental errors. In this work some of the most practical methods to get generalized masses are used: mechanical loading, quadrature component addition and the complex power method. Errors of the above methods were analyzed, and the most reliable methods were selected for flutter analysis. Comparison was made between the flutter analysis using generalized parameters and a pure theoretical one based on developing the mathematical model from the DSM design specifications. According to the design specifications, the mathematical model utilizes the beam-like schematization of the wing. The analysis was performed for Mach numbers from 0.2 to 0.8 and relative air densities of 0.5, 1, 1.5. Comparison of the two methods showed the difference in critical flutter dynamic pressure no more than 6%, which indicates good prospects of the flutter analysis based on generalized parameters of eigen modes.

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