scholarly journals On a Class of Polar Log-Aesthetic Curves

2021 ◽  
Author(s):  
Victor Parque
Keyword(s):  
Industrial Design ◽  
Polar Coordinate System ◽  
Navigation Systems ◽  
Straight Line ◽  
Manufactured Products ◽  
Bird Eggs ◽  
Polar Coordinate ◽  
Specific Curvature

Abstract Curves are essential concepts that enable compounded aesthetic curves, e.g., to assemble complex silhouettes, match a specific curvature profile in industrial design, and construct smooth, comfortable, and safe trajectories in vehicle-robot navigation systems. New mechanisms able to encode, generate, evaluate, and deform aesthetic curves are expected to improve the throughput and the quality of industrial design. In recent years, the study of (log) aesthetic curves have attracted the community’s attention due to its ubiquity in natural phenomena such as bird eggs, butterfly wings, falcon flights, and manufactured products such as Japanese swords and automobiles. A (log) aesthetic curve renders a logarithmic curvature graph approximated by a straight line, and polar aesthetic curves enable to mode user-defined dynamics of the polar tangential angle in the polar coordinate system. As such, the curvature profile often becomes a by-product of the tangential angle. In this paper, we extend the concept of polar aesthetic curves and establish the analytical formulations to construct aesthetic curves with user-defined criteria. In particular, we propose the closed-form analytic characterizations of polar log-aesthetic curves meeting user-defined criteria of curvature profiles and dynamics of polar tangential angles. We present numerical examples portraying the feasibility of rendering the logarithmic curvature graphs represented by a straight line. Our approach enables the seamless characterization of aesthetic curves in the polar co-ordinate system, which can model aesthetic shapes with desirable aesthetic curvature profiles.

scholarly journals Nearly Reversible ECG Steganography based on Polar Coordinate System with Digital Replacement Technique

2021 ◽  
Vol 9 (6) ◽  
pp. 9-19
Author(s):  
CHING YU YANG ◽  
Chi-Kai Huang
Keyword(s):  
Coordinate System ◽  
Signal To Noise Ratio ◽  
Personal Data ◽  
Polar Coordinate System ◽  
Measuring Instruments ◽  
Replacement Technique ◽  
Polar Coordinate ◽  
Electrocardiogram Ecg ◽  
High Payload

In this paper, we present a nearly reversible data hiding for electrocardiogram (ECG) hosts. Based on the polar coordinate system domain, medical diagnosis and personal data can be embedded in an ECG signal by the simple digital replacement technique. Simulations revealed that the restored ECG with near lossless quality can be obtained by the proposed method at receiver site. In addition, the perceived quality of the marked ECG is very good with a high payload size. Moreover, the resultant signal-to-noise ratio (SNR), peak SNR, and payload of the proposed method outperforms those of existing techniques. Since the computation cost is low, the proposed method can be used in portable biometrics or ECG measuring instruments.

scholarly journals Quantitative Characterization of Molecular-Stream Separation

2019 ◽  
Author(s):  
Sven Kochmann ◽  
Sergey N. Krylov
Keyword(s):  
Continuous Flow ◽  
Separation Zone ◽  
Physicochemical Characteristics ◽  
Polar Coordinate System ◽  
Signal Integration ◽  
Quantitative Characterization ◽  
The Third ◽  
Stream Width ◽  
Polar Coordinate

Molecular-stream separation (MSS), e.g. by free flow electrophoresis or continuous annular chromatography, has great potential for applications that require continuous downstream separation such continuous flow synthesis. Despite its potential, MSS still needs to be greatly advanced, which requires currently lacking tools for quantitative characterization of streams in MSS. We developed and introduce here an analytical toolbox for this task. The first tool is a method to convolute 3D raw MSS data into a 2D “angulagram” via signal integration over the whole separation zone using a polar coordinate system. The second tool is three quantitative parameters characterizing stream width, linearity, and deflection, which are determined from an angulagram. The third tool is the analysis of the three parameters in relation to physicochemical characteristics of MSS which reveals deficiencies and guides improvements in MSS devices and methods. Examples of toolbox application to validation of previously published MSS data are provided.

scholarly journals Analysis of Linear Surfaces of Building Structures

2020 ◽  
Vol 24 (3) ◽  
pp. 111-120
Author(s):  
S. N. Volkova ◽  
A. V. Shleenko ◽  
V. V. Morozova ◽  
E. E. Sivak
Keyword(s):  
Cylindrical Surface ◽  
Construction Material ◽  
Second Order ◽  
Polar Coordinate System ◽  
Arbitrary Parameter ◽  
Building Structures ◽  
Straight Line ◽  
Polar Coordinate ◽  
Third Dimension ◽  
Straight Lines

Purpose of reseach is to analyze the practice in the application of surfaces formed by the movement of a straight line. It is known that among the second-order surfaces cones, cylinders, hyperboloids of one sheet and hyperbolic paraboloids, as well as lines represented in the polar coordinate system in the form of intricate shapes that can be represented in space by the above-mentioned surfaces, adding a third dimension, have rectilinear generators. The strength resulting from covering each point of the listed surfaces with straight lines from different families does not make the structure heavier but strengthens it and makes it light compared to monoliths without reinforcements made of other materials, in which stability is not based on Shukhov calculation formulas. Methods Finding families of rectilinear generators for second-order surfaces calculation of which is based on the separation of equations that represent a second-order surface as a difference of squares in one part of the equation and as a product with an arbitrary parameter in the other part. Results. Analyzing second-order surfaces, we came to the conclusion that cones, cylinders are prone to this method of Shukhov calculations; equation of the form F (x,y)=0 in space defines a cylindrical surface whose generators are parallel to axis oz. Similarly, F (x, z)=0 defines a cylindrical surface with generators parallel to axis oy and F (y;z)=0 is a cylindrical surface with generators parallel to axis ox. A hyperboloid of one sheet, hyperbolic paraboloid, i.e. 10 surfaces out of 14, make up more than 70%. Conclusion. As a result of applying these formulas for calculating reinforced building structures, city buildings will acquire a new appearance, which will create a comfortable environment for residents, as well as lead to saving construction material resources.

scholarly journals Advances in Multi-Scale Mechanical Characterization of Materials with Optical Methods

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7282
Author(s):  
Luciano Lamberti
Keyword(s):  
Mechanical Characterization ◽  
Optical Methods ◽  
Manufacturing Processes ◽  
Material Microstructure ◽  
Multi Scale ◽  
Manufactured Products ◽  
Characterization Of Materials ◽  
Process Speed

The mechanical characterization of materials embraces many different aspects, such as, for example, (i) to assess materials’ constitutive behavior under static and dynamic conditions; (ii) to analyze material microstructure; (iii) to assess the level of damage developed in the material; (iv) to determine surface/interfacial properties; and (v) to optimize manufacturing processes in terms of process speed and reliability and obtain the highest quality of manufactured products [...]

scholarly journals Quantitative Characterization of Molecular-Stream Separation

2018 ◽  
Author(s):  
Sven Kochmann ◽  
Sergey N. Krylov
Keyword(s):  
Continuous Flow ◽  
Separation Zone ◽  
Physicochemical Characteristics ◽  
Polar Coordinate System ◽  
Signal Integration ◽  
Quantitative Characterization ◽  
The Third ◽  
Stream Width ◽  
Polar Coordinate

Molecular-stream separation (MSS), e.g. by free flow electrophoresis or continuous annular chromatography, has great potential for applications that require continuous downstream separation such continuous flow synthesis. Despite its potential, MSS still needs to be greatly advanced, which requires currently lacking tools for quantitative characterization of streams in MSS. We developed and introduce here an analytical toolbox for this task. The first tool is a method to convolute 3D raw MSS data into a 2D “angulagram” via signal integration over the whole separation zone using a polar coordinate system. The second tool is three quantitative parameters characterizing stream width, linearity, and deflection, which are determined from an angulagram. The third tool is the analysis of the three parameters in relation to physicochemical characteristics of MSS which reveals deficiencies and guides improvements in MSS devices and methods. Examples of toolbox application to validation of previously published MSS data are provided.

scholarly journals Quantitative Characterization of Molecular-Stream Separation

2019 ◽  
Author(s):  
Sven Kochmann ◽  
Sergey N. Krylov
Keyword(s):  
Continuous Flow ◽  
Separation Zone ◽  
Physicochemical Characteristics ◽  
Polar Coordinate System ◽  
Signal Integration ◽  
Quantitative Characterization ◽  
The Third ◽  
Stream Width ◽  
Polar Coordinate

Molecular-stream separation (MSS), e.g. by free flow electrophoresis or continuous annular chromatography, has great potential for applications that require continuous downstream separation such continuous flow synthesis. Despite its potential, MSS still needs to be greatly advanced, which requires currently lacking tools for quantitative characterization of streams in MSS. We developed and introduce here an analytical toolbox for this task. The first tool is a method to convolute 3D raw MSS data into a 2D “angulagram” via signal integration over the whole separation zone using a polar coordinate system. The second tool is three quantitative parameters characterizing stream width, linearity, and deflection, which are determined from an angulagram. The third tool is the analysis of the three parameters in relation to physicochemical characteristics of MSS which reveals deficiencies and guides improvements in MSS devices and methods. Examples of toolbox application to validation of previously published MSS data are provided.

Physicochemical and bacteriological characterization of hospital effluents and their impact on the environment

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Human Health ◽  
Fecal Coliforms ◽  
Chemical Pollution ◽  
Hospital Effluents ◽  
Biological Contaminants ◽  
Almost All ◽  
Direct Discharge ◽  
Significant Chemical

Liquid effluents discharged by hospitals may contain chemical and biological contaminants whose main source is the different substances used for the treatment of patients. This type of rejection can present a sanitary potentially dangerous risk for human health and can provoke a strong degradation of diverse environmental compartments mainly water and soils. The present study focuses on the quality of the liquid effluents of Hassani Abdelkader’s hospital of Sidi Bel-Abbes (West of Algeria). The results reveal a significant chemical pollution (COD: 879 mgO2/L, BOD5: 850 mgO2/L, NH4+ : 47.9 mg/l, NO2- : 4.2 mg/l, NO3- : 56.8 mg/l with respect to WHO standard of 90 mgO2/L, 30 mgO2/L, 0.5 mg/l, 1 mg/l and 1 mg/l respectively). However, these effluents are biodegradable since the ratio COD/BOD5 do not exceeded the value of 2 in almost all samples. The presence of pathogen germs is put into evidence such as pseudomonas, the clostridium, the staphylococcus, the fecal coliforms and fecal streptococcus. These results show that the direct discharge of these effluents constitutes a major threat to human health and the environment.

Statistical Management of Food Production Processes

2020 ◽  
pp. 30-35
Author(s):  
N.A. Jurk ◽  
Keyword(s):  
Production Process ◽  
Control Chart ◽  
Food Production ◽  
Time Interval ◽  
Bakery Products ◽  
Shewhart Control ◽  
Manufactured Products ◽  
Mnemonic Technique ◽  
The Stability

The article presents scientific research in the field of statistical controllability of the food production process using the example of bakery products for a certain time interval using statistical methods of quality management. During quality control of finished products, defects in bakery products were identified, while the initial data were recorded in the developed form of a checklist for registering defects. It has been established that the most common defect is packaging leakage. For the subsequent statistical assessment of the stability of the production process and further analysis of the causes of the identified defect, a Shewhart control chart (p-card by an alternative feature) was used, which allows you to control the quality of manufactured products by the number of defects detected. Analyzing the control chart, it was concluded that studied process is conditionally stable, and the emerging defects are random. At the last stage of the research, the Ishikawa causal diagram was used, developed using the 6M mnemonic technique, in order to identify the most significant causes that affect the occurrence of the considered defect in bakery products. A more detailed study will allow the enterprise to produce food products that meet the established requirements.

The influence of unintentional radio interference on the equipment operation quality of satellite radio navigation systems consumers

2020 ◽  
pp. 165-170
Keyword(s):  
Underlying Surface ◽  
Navigation Systems ◽  
Signal Attenuation ◽  
Radio Navigation ◽  
Equipment Operation ◽  
Atmospheric Noise ◽  
Detection Mode ◽  
Signal Mode ◽  
Cosmic Noise

The analysis an influence of reflections from the underlying surface, atmospheric noise, the Earth’s surface, cosmic noise and signal attenuation of the signal the atmosphere, as well as the flight dynamics of the aircraft (AC) on the signal/noise ratio and, accordingly, on the accuracy of AC navigation definitions by using consumer equipment of the satellite radio navigation systems. The analysis an influence of reflections from the underlying surface on the equipment operation quality of the satellite radio navigation systems consumers is carried out by using the Beckman model, in accordance with the earth’s surface appears to consist of flat faces with an arbitrary slope. It is noted that reflections from the underlying surface have a greater effect on the quality of functioning of the consumer equipment of the satellite radio navigation systems in the tracking signal mode than in the detection mode. In this case, the influence of reflections increases with decreasing flight altitude and an increase in the angle of heel of the AC in the direction of the navigation spacecraft.

О ТОЧНОСТИ ОПРЕДЕЛЕНИЯ КООРДИНАТ ПОДВОДНОГО МОДУЛЯ НА ОСНОВЕ ИЗМЕРЕННЫХ ПАРАМЕТРОВ ДВИЖЕНИЯ БУКСИРУЕМОЙ СИСТЕМЫ

2020 ◽  
Author(s):  
V.V. Kostenko ◽  
Yu.V. Vaulin ◽  
F.S. Dubrovin ◽  
O.Yu. Lvov
Keyword(s):  
Immersion Depth ◽  
Computational Algorithms ◽  
Navigation Systems ◽  
Short Baseline ◽  
Positioning Accuracy ◽  
Underwater Acoustic ◽  
Ground Speed ◽  
Cable Length ◽  
Acoustic Navigation

Буксируемый подводный модуль (БПМ) эффективно используется для решения задач, связанных с координированием подводных объектов, местоположение которых подлежит уточнению в процессе их детальногообследования. При этом большое значение имеет точность определения координат самого буксируемогомодуля относительно судна-буксировщика. Использование гидроакустических навигационных средств, вчастности систем с ультракороткой базой (ГАНС УКБ), ограничено вследствие помех, влияющих на качествосигналов в приемной антенне. Альтернативой служит метод определения координат БПМ на основе данныхтраекторных измерений параметров буксируемой системы. К числу последних относятся расчетные значенияпараметров кабеля связи в установившихся режимах буксировки, значения путевой скорости и путевого углабуксировщика, а также измеренные значения длины кабеля, глубины погружения и курса БПМ. В работе дансравнительный анализ различных вариантов вычислительных алгоритмов, позволяющих получить оценки точности определения координат БПМ в различных режимах стационарной буксировки и при наличии сбоев вработе навигационных средств.The towed underwater module (TUM) is a useful toolfor solving problems of the positioning of the underwaterobjects, the location of which must be clarified during its detailedinspection. Herewith, the accuracy of the determinationof the coordinates of the towed module itself relative tothe towing vessel is essential for such kind of problems. Theuse of underwater acoustic navigation means, the systemswith ultra-short baseline (USBL) in particular, are limiteddue to interference affecting the quality of the signals on thereceiving antenna. As an alternative, the method is proposedfor TUM positioning based on trajectory measurements ofparameters of the towed system, which may include calculatedvalues of communication cable parameters in steadystatetowing modes, values of ground speed and towing angle,as well as measured cable length, immersion depth, andTUM heading. The paper provides a comparative analysisof various versions of computational algorithms, which allowobtaining estimates of the TUM positioning accuracy indifferent modes of stationary towing and in the presence offailures in navigation systems operation.

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