• Title/Summary/Keyword: mathematical content

Search Result 576, Processing Time 0.024 seconds

Circulating Concurrent-flow Drying Simulation of Rapeseed (순환식 병류형 유채씨 건조 시뮬레이션)

  • Han, Jae-Woong;Keum, Dong-Hyuk;Kim, Woong;Duc, Le Anh;Cho, Sung-Ho;Kim, Hoon
    • Journal of Biosystems Engineering
    • /
    • v.35 no.6
    • /
    • pp.401-407
    • /
    • 2010
  • In this study, computer simulations were conducted to assess the use of a circulating concurrent-flow dryer for rapeseed drying and to determined the effect of this drying method on the germination ratio of rapeseed after the drying process was complete. The simultaneous heat and mass transfer between air and rapeseed in a concurrent-flow dryer was examined by simulation. The drying simulation was based on several parameters with sequent time series. Equations concerning air psychrometrics, physical properties, thermal properties, equilibrium moisture content, thin layer drying of rapeseed, etc. were all combined to solve the simulation models. Based on energy and mass transfer in the concurrent-flow drying model, a simulation program for the circulating concurrent-flow rapeseed dryer was built along with a detailed description of the mathematical solution to the model. A pilot scale circulating concurrent-flow dryer(200 kg/batch) was used to verify the fitness of the simulation program. A comparison between the experimental data and the model predicted results was presented and discussed. The drying parameters and germination ratio were analyzed and the accuracy of the simulation program was evaluated. The simulation program proved to be reliable and was shown to be a convenient tool for predicting rapeseed drying and germination ratio of rapeseed in a concurrent-flow dryer.

Qualitative Analysis on Mixed Research in the field of Mathematics for Elementary Students (초등 수학교육 관련 혼합 연구에서 적용된 질적 연구 방법에 대한 분석)

  • Na, Jang Ham;Kim, Jinho
    • Education of Primary School Mathematics
    • /
    • v.19 no.1
    • /
    • pp.47-60
    • /
    • 2016
  • The purpose of this study is to analyze how the qualitative research is applied to mixed method research and thereby to gain an insight to suggest reasonable ways of employing qualitative method in order to accomplish intended goal of research, especially in the field of mathematics education. For that purpose, this study carefully selects and analyzes 5 article that used mixed method and were published by Education of Primary School Mathematics Journal in 2012. Unlike those a few previous studied on mixed method that focused on producing general trend by simply showing quantitative information on what the frequence of used research topic, content, methods combination, quantitative methods, and qualitative methods, this study provides detailed result of qualitative analysis on mixed studies. In sum, this study concludes with practical and in-depth suggestions on how to improve validity of mixed research and qualitative research in the field of mathematic of education.

Neutron-shielding behaviour investigations of some clay-materials

  • Olukotun, S.F.;Mann, Kulwinder Singh;Gbenu, S.T.;Ibitoye, F.I.;Oladejo, O.F.;Joshi, Amit;Tekin, H.O.;Sayyed, M.I.;Fasasi, M.K.;Balogun, F.A.;Korkut, Turgay
    • Nuclear Engineering and Technology
    • /
    • v.51 no.5
    • /
    • pp.1444-1450
    • /
    • 2019
  • The fast-neutron shielding behaviour (FNSB) of two clay-materials (Ball clay and Kaolin)of Southwestern Nigeria ($7.49^{\circ}N$, $4.55^{\circ}E$) have been investigated using effective removal cross section, ${\Sigma}_R(cm^{-1})$, mass removal cross section, ${\Sigma}_{R/{\rho}}(cm^2g^{-1})$ and Mean free path, ${\lambda}$ (cm). These parameters decide neutron shielding behaviour of any material. A computer program - WinNC-Toolkit has been used for computation of these parameters. The toolkit evaluates these parameters by using elemental compositions and densities of samples. The proficiency of WinNC-Toolkit code was probe by using MCNPX and GEANT4 to model fast neutron transmission of the samples under narrow beam geometry, intending to represent the actual experimental setup. Direct calculation of effective removal cross section ($cm^{-1}$) of the samples was also carried out. The results from each of the methods for each types of the studied clay-materials (Ball clay and Kaolin) shows similar trend. The trend might be the fingerprint of water content retained in each of the samples being baked at different temperature. The compositions of each sample have been obtained by Particle-Induced X-ray Emission (PIXE) technique (Tandem Pelletron Accelerator: 1.7 MV, Model 5SDH). The FNSB of the selected clay-materials have been compared with standard concrete. The cognizance of various factors such as availability, thermo-chemical stability and water retaining ability by the clay-samples can be analyzed for efficacy of the material for their FNSB.

An Analysis on the Contents of Fractional Operations in CCSSM-CA and its Textbooks (CCSSM-CA와 미국 교과서에 제시된 분수의 연산 내용 분석)

  • Lee, Dae Hyun
    • Education of Primary School Mathematics
    • /
    • v.22 no.2
    • /
    • pp.129-147
    • /
    • 2019
  • Because of the various concepts and meanings of fractions and the difficulty of learning, studies to improve the teaching methods of fraction have been carried out. Particularly, because there are various methods of teaching depending on the type of fractions or the models or methods used for problem solving in fraction operations, many researches have been implemented. In this study, I analyzed the fractional operations of CCSSM-CA and its U.S. textbooks. It was CCSSM-CA revised and presented in California and the textbooks of Houghton Mifflin Harcourt Publishing Co., which reflect the content and direction of CCSSM-CA. As a result of the analysis, although the grades presented in CCSSM-CA and Korean textbooks were consistent in the addition and subtraction of fractions, there are the features of expressing fractions by the sum of fractions with the same denominator or unit fraction and the evaluation of the appropriateness of the answer. In the multiplication and division of fractions, there is a difference in the presentation according to the grades. There are the features of the comparison the results of products based on the number of factor, presenting the division including the unit fractions at first, and suggesting the solving of division problems using various ways.

Physical and numerical modelling of the inherent variability of shear strength in soil mechanics

  • Chenari, Reza Jamshidi;Fatahi, Behzad;Ghoreishi, Malahat;Taleb, Ali
    • Geomechanics and Engineering
    • /
    • v.17 no.1
    • /
    • pp.31-45
    • /
    • 2019
  • In this study the spatial variability of soils is substantiated physically and numerically by using random field theory. Heterogeneous samples are fabricated by combining nine homogeneous soil clusters that are assumed to be elements of an adopted random field. Homogeneous soils are prepared by mixing different percentages of kaolin and bentonite at water contents equivalent to their respective liquid limits. Comprehensive characteristic laboratory tests were carried out before embarking on direct shear experiments to deduce the basic correlations and properties of nine homogeneous soil clusters that serve to reconstitute the heterogeneous samples. The tests consist of Atterberg limits, and Oedometric and unconfined compression tests. The undrained shear strength of nine soil clusters were measured by the unconfined compression test data, and then correlations were made between the water content and the strength and stiffness of soil samples with different consistency limits. The direct shear strength of heterogeneous samples of different stochastic properties was then evaluated by physical and numerical modelling using FISH code programming in finite difference software of $FLAC^{3D}$. The results of the experimental and stochastic numerical analyses were then compared. The deviation of numerical simulations from direct shear load-displacement profiles taken from different sources were discussed, potential sources of error was introduced and elaborated. This study was primarily to explain the mathematical and physical procedures of sample preparation in stochastic soil mechanics. It can be extended to different problems and applications in geotechnical engineering discipline to take in to account the variability of strength and deformation parameters.

A study on the establishment of a differential standardization system for the franchisor for a successful math franchise business (성공적인 수학 프랜차이즈 사업을 위한 가맹본부의 차별화된 표준화 시스템 구축방안에 관한 연구)

  • Hong, Hee-dong
    • Journal of the Korea Convergence Society
    • /
    • v.13 no.4
    • /
    • pp.63-70
    • /
    • 2022
  • Due to the recent changes in the education market and Corona, Consumers have moved to the tutoring and online learning markets, and the large-scale education service franchise business is reorganized into a small-scale franchise, a business model that maximizes the profit structure from a position where sales are important. Recently, a new learning balance model that can provide individualized services from teacher-centered to student-centered, motivate students is required. In this paper, we propose a new mathematical franchise model (K-MODEL) that can improve a company's profit structure while satisfying the recent education trends and consumer needs from the point of view of the franchise. K-MODEL expects franchisor and franchisees to have a stable profit structure by developing differentiated content and services, learning and operating processes, and various programs to improve learning achievement.

Preservice Elementary Mathematics Teachers' Curricular Noticing: Focusing on the Lesson Planning for Rate (초등예비교사의 교육과정에 관한 노티싱: 비율 수업을 중심으로)

  • Cho, Mi Kyung
    • Education of Primary School Mathematics
    • /
    • v.24 no.2
    • /
    • pp.83-102
    • /
    • 2021
  • Curricular noticing is about how teachers understand the content and pedagogical opportunities inherent in curriculum materials. Since the enacted curriculum differs depending on which aspect of the curriculum material is paid attention to and how to interpret it, it is necessary to focus on Curricular Attending and Curricular Interpreting in Curricular Noticing for enhancing the teaching expertise of preservice teachers. First, this study categorized the objects that preservice elementary mathematics teachers attended when planning the lesson for rate. Second, in order to find out the reason for paying attention to those objects, it was analyzed what factors were related to interpret. By discussing the results, implications were drawn on how to use Curricular Noticing in preservice teacher education to enhance the pedagogical design competency of preservice elementary mathematics teachers.

Digitalization and Diversification of Modern Educational Space (Ukrainian case)

  • Oksana, Bohomaz;Inna, Koreneva;Valentyn, Lihus;Yanina, Kambalova;Shevchuk, Victoria;Hanna, Tolchieva
    • International Journal of Computer Science & Network Security
    • /
    • v.22 no.11
    • /
    • pp.11-18
    • /
    • 2022
  • Linking Ukraine's education system with the trends of global digitalization is mandatory to ensure the sustainable, long-term development of the country, as well as to increase the sustainability of the education system and the economy as a whole during the crisis period. Now the main problems of the education system in Ukraine are manifested in a complex context caused by Russian armed aggression. In the context of war, problems include differences in adaptation to online learning among educational institutions, limited access to education for vulnerable groups in the zone of active hostilities, the lack of digital educational resources suitable for online learning, and the lack of basic digital skills and competencies among students and teachers necessary to properly conduct online classes. Some of the problems of online learning were solved in the pandemic, but in the context of war Ukrainian society needs a new vision of education and continuous efforts of all social structures in the public and private environment. In the context of war, concerted action is needed to keep education on track and restore it in active zones, adapting to the needs of a dynamic society and an increasingly digitized economy. Among the urgent needs of the education system are a change in the teaching-learning paradigm, which is based on content presentation, memorization, and reproduction, and the adoption of a new, hybrid educational model that will encourage the development of necessary skills and abilities for students and learners in a digitized society and enable citizens close to war zones to learn.

Suggestions for Setting on Period of Epidemic Waves in COVID-19 Epidemic of South Korea (한국 코로나19 유행기에 대한 제안)

  • Lee, Moo-Sik
    • Journal of agricultural medicine and community health
    • /
    • v.47 no.2
    • /
    • pp.61-66
    • /
    • 2022
  • Objectives: In the epidemiology of communicable diseases, the term epidemic period, also referred to as "wave" is often used in the general and academic milieu. A wave refers to a natural pattern of increase in the number of sick individuals, a defined peak, and then a decline in the number of cases. It implies a pattern of peaks and valleys after a particular peak is taken. The idea of epidemic waves is a useful tool for predicting the course as well as helping to accurately describe an epidemic. However, in many domestic and foreign news as well as in various research results in Korea, most of the reports either had no standard, were inaccurate, had a questionable classification of the period of the epidemic, or the basis for classification of a given wave was not presented. Methods: The author reviewed and organized related literature with epidemic wave. The author made several suggestions of an epidemic wave as follows. Results: To start with, it should be based on the number of incident cases in consideration of the size of the outbreak, then the period from the bottom to the peak and then reaching the next bottom; also, the period over a certain scale based on the number of incident cases; and the period according to the change in the major infection type (mutation-dominant species). In addition, according to the period of change in the vaccination rate (formation of herd immunity), as well as the content and duration of the intervention, that is, classification according to the applied quarantine stage. Furthermore, the classification of epidemic periods by the time-dependent reproduction number or time-varying reproduction number (Rt), and lastly the application of mathematical methodology. Conclusions: Therefore, classifying the epidemic period into generally known and accepted time frames is considered to be a very important task for future research analysis and development of intervention strategies.

An Analysis of Elementary School Teachers' Educational Needs on Designing Interactions for Online Mathematics Lessons (온라인 수학 수업에서 상호작용 설계에 대한 초등교사의 교육요구도 분석)

  • Cho, Mi Kyung;Kim, Seyoung
    • Education of Primary School Mathematics
    • /
    • v.25 no.1
    • /
    • pp.19-41
    • /
    • 2022
  • Online classes have become one of the general teaching and learning method in elementary education, and elementary school teachers are essentially required to design and implement online math classes that reflect the characteristics of online environment and the specificity of the subject. The qualitative improvement of online mathematics lessons can start with examining what difficulties teachers actually have in enacting the online lessons, and this study focused on their educational needs by examining the degree to which elementary school teachers perceive and implement in terms of designing online interactions. The result showed that teacher education on Learner-Content Interaction (LC) and Learner-Learner Interaction (LL) was necessary for elementary school teachers designing online mathematics lessons, and the educational needs of detailed items of interactions were confirmed. Furthermore, it was found that there was a difference in educational needs for the types of online interactions according to the career life cycle of elementary school teachers. The instructional design strategies for online interactions in online mathematics lessons and implications for teacher education necessary for elementary school teachers were derived from the result.