The State of Primary School Third-Grade Pupils’ Making Sense of the Concepts of “0” and “1”

This paper focuses on determining the opinions of primary school third-grade pupils about the conceptual meaning and use of the numbers “0” and “1”. The current study employed the case study design, which is one of the qualitative research methods. In the selection of the sample, the criterion sampling method, one of the purposive sampling methods, was used. The study was conducted with the participation of a total of 114 third-grade pupils (58 girls and 56 boys) attending two state primary schools located in the city of Ankara in the fall term of the 2019-2020 school year. As the data collection tool, a semi-structured interview form developed by the researchers in relation to the concepts of “0” and “1” was used. In the analysis of the data obtained in relation to the concepts of “0” and “1”, content analysis was used. The primary school third-grade pupils made sense of the number “0” in association with the categories of four operations, ineffective element, absorbing element, number, natural number, meaningless, valueless, absence, even number, beginning, and letter. The categories in which most thoughts about the meaning of the number “1” are gathered are number, ineffective element, and uniqueness. It was determined that the pupils are more successful in the use of the numbers “0” and “1” in the addition and subtraction operations than in the multiplication and division operations.

An Improved Total Uncertainty Measure in the Evidence Theory and Its Application in Decision Making

Dempster–Shafer evidence theory (DS theory) has some superiorities in uncertain information processing for a large variety of applications. However, the problem of how to quantify the uncertainty of basic probability assignment (BPA) in DS theory framework remain unresolved. The goal of this paper is to define a new belief entropy for measuring uncertainty of BPA with desirable properties. The new entropy can be helpful for uncertainty management in practical applications such as decision making. The proposed uncertainty measure has two components. The first component is an improved version of Dubois–Prade entropy, which aims to capture the non-specificity portion of uncertainty with a consideration of the element number in frame of discernment (FOD). The second component is adopted from Nguyen entropy, which captures conflict in BPA. We prove that the proposed entropy satisfies some desired properties proposed in the literature. In addition, the proposed entropy can be reduced to Shannon entropy if the BPA is a probability distribution. Numerical examples are presented to show the efficiency and superiority of the proposed measure as well as an application in decision making.

Approach to 3D Unsteady CFD Analysis of a Single-Blade Pump

Single-blade centrifugal pumps are hydraulic machines used in many industrial areas. A unique screw shaped blade enables liquids containing solids and fibrous matters to be pumped. Owing to good pump hydraulic properties on the one hand and unfavourable impeller mechanical properties on the other have single-blade pumps become recently more interesting for researchers regarding the CFD simulations. In this case a conventional CFD approach for multi-blade pumps cannot be applied due to the lack of symmetry of the single-blade impeller. Possible approaches to the CFD simulation of a single-blade impeller in the Ansys Fluent and the Ansys CFX are compared in this paper. A comparison of two CFD meshing tools showed substantial element number decrease of the whole CFD model. This paper presents also the laboratory experiment results of the investigated single-blade pump. The paper describes a new approach to the single-blade CFD simulation through Ansys Fluent which is faster and more user-friendly then the conventional approach.

Optimization of Two-Stage Combined Thermoelectric Devices by a Three-Dimensional Multi-Physics Model and Multi-Objective Genetic Algorithm

Due to their advantages of self-powered capability and compact size, combined thermoelectric devices, in which a thermoelectric cooler module is driven by a thermoelectric generator module, have become promising candidates for cooling applications in extreme conditions or environments where the room is confined and the power supply is sacrificed. When the device is designed as two-stage configuration for larger temperature difference, the design degree is larger than that of a single-stage counterpart. The element number allocation to each stage in the system has a significant influence on the device performance. However, this issue has not been well-solved in previous studies. This work proposes a three-dimensional multi-physics model coupled with multi-objective genetic algorithm to optimize the optimal element number allocation with the coefficient of performance and cooling capacity simultaneously as multi-objective functions. This method increases the accuracy of performance prediction compared with the previously reported examples studied by the thermal resistance model. The results show that the performance of the optimized device is remarkably enhanced, where the cooling capacity is increased by 23.3% and the coefficient of performance increased by 122.0% compared with the 1# Initial Solution. The mechanism behind this enhanced performance is analyzed. The results in this paper should be beneficial for engineers and scientists seeking to design a combined thermoelectric device with optimal performance under the constraint of total element number.

Hybrid Bacterial Foraging Optimization – Tabu Search for Medical Image Classification

Delicate registering is presented in the preparing of restorative picture as is has a viable way to deal with the treatment of vulnerabilities that are inborn in the procured picture information. It has space that is high-dimensional which can debase the picture characterization execution principally as far as its exactness for structure an order display as it contains certain excess and unimportant highlights. Accordingly, include choice has been utilized for the decrease of the element number that is separated from pictures by methods for evacuating any excess or insignificant highlights. The meta-heuristics have been creating for a significant drawn-out period of time and are accepting an imperative employment in the fields of the administrators and money related issues. Among all the present computations, TABU chase (TS) has been appearing couple of productive applications to issues of this present reality that is demonstrate by innumerable all the world over. Picture enlistment or picture course of action is a fundamental development in remedial picture examination when various pictures are incorporated. In by far most of such applications, the selection is performed following the power based strategy, which changes IR into a complex, computationally expensive, steady progression issue

The equipment for determining the impact of traffic environment on road pavement

The article presents the classification of equipment developed by the author for the research of the operational characteristics of road pavement. The equipment was classified according to the following criteria: type of equipment; type of contact element; mode of interaction with the supporting surface; type of fixture of the suspension element; number of contact elements; sample type; type of load. For illustrations, the classification of the most common equipment was carried out. The research was conducted to compare and select the most rational equipment to study the effect of traffic environment on the road pavement. The research was carried out by the multi-criteria analysis. Based on the conducted research, the most rational installations for conducting experiments were determined.

A Novel Racing Array Transducer for Noninvasive Ultrasonic Retinal Stimulation: A Simulation Study

Neurostimulation has proved to be an effective method for the restoration of visual perception lost due to retinal diseases. However, the clinically available retinal neurostimulation method is based on invasive electrodes, making it a high-cost and high-risk procedure. Recently, ultrasound has been demonstrated to be an effective way to achieve noninvasive neurostimulation. In this work, a novel racing array transducer with a contact lens shape is proposed for ultrasonic retinal stimulation. The transducer is flexible and placed outside the eyeball, similar to the application of a contact lens. Ultrasound emitted from the transducer can reach the retina without passing through the lens, thus greatly minimizing the acoustic absorption in the lens. The discretized Rayleigh–Sommerfeld method was employed for the acoustic field simulation, and patterned stimulation was achieved. A 5 MHz racing array transducer with different element numbers was simulated to optimize the array configuration. The results show that a 512-element racing array is the most appropriate configuration considering the necessary tradeoff between the element number and the stimulation resolution. The stimulation resolution at a focus of 24 mm is about 0.6 mm. The obtained results indicate that the proposed racing array design of the ultrasound transducer can improve the feasibility of an ultrasound retinal prosthesis.