Blaschke, Separation Theorems and some Topological Properties for Orthogonally Convex Sets

In this paper, we deal with analytic and geometric properties of orthogonally convex sets. We establish a Blaschke-type theorem for path-connected and orthogonally convex sets in the plane using orthogonally convex paths. The separation of these sets is established using suitable grids. Consequently, a closed and orthogonally convex set is represented by the intersection of staircase-halfplanes in the plane. Some topological properties of orthogonally convex sets in dimensional spaces are also given.Comment: 17 pages, 10 figures, adding more reference

Multi-Response Optimization of Burnishing Variables for Minimizing Environmental Impacts

The purpose of this investigation is to optimize minimum quantity lubrication (MQL) variables, including the nozzle diameter (D), inclined angle (A), air pressure (P), oil quantity (F), and spraying distance (S) for decreasing the energy consumption in the burnishing time (EB) and particulate matter index (PI) of the interior burnishing process. The optimal adaptive neuro-based-fuzzy inference system (ANFIS) models of the performance measures were proposed in terms of the MQL variables with the aid of the Taguchi method. The non-dominated sorting genetic algorithm based on the grid partitioning (NSGA-G) and TOPSI were employed to produce feasible solutions and determine the best optimal point. The obtained results indicated that the optimal values of the D, A, P, F, and S are 1.0 mm, 35 deg., 3 Bar, 70 ml/h, and 10 mm, respectively, while the EB and PI are decreased by 8.0% and 15.7% at the optimal solution. The optimal ANFIS models were trustworthy and ensure accurate predictions. The optimization technique comprising the ANFIS, NSGA-G, and TOPSIS could be extensively utilized to determine the optimal outcomes instead of the trial-error and/or human experience. The outcomes could help to decrease environmental impacts in the practical burnishing process

Understanding Conceptual Design Activities: Extended Axiomatic Theory of Design Modeling and Physiological Experimentation

Conceptual design is an early and critical phase of a design process. Decisions made in this stage can affect seventy five percent of the manufacturing costs. Therefore, one of the important factors to successful production is to have methods and tools that enable designers to work more effectively during the phase of conceptual design. To build such methods and tools, knowledge of design activities such as nature of the design process and factors affecting design activities is indispensable. The present thesis is a continuing effort to build a science of design which aims to discover knowledge of design activities through formal scientific process. The contribution of the current thesis includes the extended Axiomatic Theory of Design Modelling and methodologies to study design cognition physiologically. In particular, two postulates were added to the Axiomatic Theory of Design Modelling to support its explanatory power which was demonstrated through the interpretation of the impact of sketching on design performance and the occurrence of design fixation. An integrated experimental environment was developed to collect and analyze physiological signals during design processes. From this environment, several experiments recording physiological signals were conducted and findings of electroencephalography, heart rate variability, and skin conductance were reported

Vision based curve reconstruction algorithms and their application to graphical password

Curve reconstruction is the problem of approximating a curve or multiple curves from a point cloud. Curve reconstruction problem has received numerous attention over the last few decades due to its significant application in geometric modeling. In this thesis, based on the relationship between human vision and curve reconstruction, two Gestalt laws have been identified for the curve reconstruction: the law of proximity indicating that our vision tends to perceptually group near objects together and the law of continuation pointing out that objects following a consistent continuous direction are perceptually grouped together. Two algorithms have been proposed to implement these two laws in curve reconstruction. This first algorithm, DISCUR, connects points based on the law of proximity. The second algorithm, VICUR, considers both laws. The algorithms have been compared to the main curve reconstruction algorithms available in the literature. Another contribution of this thesis is a new application of curve reconstruction in the field of cryptography. In the thesis, a new graphical password scheme is introduced. The proposed scheme requires users to create their secret by selecting individual points or by connecting points into curves from a given set of points. It is reasonable to assume that the users will connect points into curves that look natural to their vision so that they can recall easily. Consequently, the password may be a part of the reconstructed results of the human-vision based curve reconstruction algorithms and the attacker can use these results to crack the password. We present the application of curve reconstruction algorithm in the evaluation of our graphical password scheme

An Image-Based Rice Weighing Estimation Approach on Clock Type Weighing Scale Using Deep Learning and Geometric Transformations

AI impacts surrounding human life, such as the economy, health, education, and agricultural production; however, the crop prices in the harvest season are still on manual calculation, which causes doubts about accuracy. In this study, an image-based approach is proposed to help farmers calculate rice prices more accurately. YOLOv5 is used to detect and extract the scales in the images taken from the harvesting of rice crops. Then, various image processing techniques, such as brightness balance, background removal, etc., are compiled to determine the needle position and number on the extracted scale. Lastly, geometric transformations are proposed to calculate the weight. A real dataset of 709 images is used for the experiment. The proposed method achieves good results in terms of [email protected] at 0.995, mAP@[0.5:0.95] at 0.830 for scale detection, and MAE at 3.7 for weight calculation

Investigation of Ultrasonic Pulse Velocity Reduction in Reinforced Concrete Members Exposed to High Temperature

Nowadays, the fire resistance of reinforced concrete members is generally defined by material characteristics at elevated temperatures and temperature functions. However, the influence of steel reinforcement in concrete members exposed to high temperatures on the ultrasonic pulse velocity (UPV) measurements has still been limited. In this paper, the quality of concrete and steel reinforcement/concrete interface was assessed under high temperatures using UPV measurements. The specimens were classified into four categories: the control tested cubes without rebar; tested cubes with plain and ribbed steel rebars. Tested cubes with dimensions of 100x100x100 mm were cast and cured for 28 days at room temperature (20oC). After drying all specimens at 105oC for 48 hours, these cubes were subjected to four different temperature levels ranging from 150oC to 400oC for 4 hours before being cooled to room temperature. According to the measured values of UPV, the higher the temperature attained in specimens, the greater the following changes occurred in concrete: (i) the degradation within the concrete; (ii) the debonding of steel reinforcements in concrete

The Relationship between Budget Revenue - expenditure and Inflation in Vietnam: Viewed from the Results of Quantitative Analysis

The research examines the relationship between budget revenue expenditure and inflation in Vietnam, with time series data on budget revenue expenditure and the consumer price index (CPI) (representing the inflation variable in Vietnam). Data were collected from the International Financial Statistics (IFS-IMF), General Statistics Office (GSO) in the period of 2005-2022. The author used Eview software to build a linear relationship log-log of budget revenue - -expenditure and CPI in the case of the Vietnamese economy. Quantitative analysis results show that when budget revenue increased by 1%, CPI increased by 0.249674%, when budget expenditure increased by 1%, CPI increased by 0.298316%. Raising budget revenue to raise budget expenditure will result in higher inflation during the research period in Vietnam. From the theoretical basis, research overview, and quantitative analysis results, the research team makes some recommendations for fiscal policy in Vietnam in the current context