• Proceedings of the CALSEC Conference
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• 2004.02a
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• pp.15-20
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• 2004

Positivism ▣Quantitative research ▣Descriptive, predictive, explanatory ▣Quest for university laws ▣Concerned with the empirical testability of theories (·Causal models (if it's not about cause-and-effect, it's not Science)) ▣Assumptions：(·Existence of a priori fixed relationship within phenomena ·Regular patterns of causation ·Independent from human mind(objective, factual)(omitted)

• Steel and Composite Structures
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• v.45 no.3
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• pp.305-330
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• 2022

This article aims to investigate the static deflection and stress analysis of bi-directional functionally graded porous plate (BDFGPP) modeled by unified higher order kinematic theories to include the shear stress effects, which not be considered before. Different shear functions are described according to higher order models that satisfy the zero-shear influence at the top and bottom surfaces, and hence refrain from the need of shear correction factor. The material properties are graded through two spatial directions (i.e., thickness and length directions) according to the power law distribution. The porosities and voids inside the material constituent are described by different cosine functions. Hamilton's principle is implemented to derive the governing equilibrium equation of bi-directional FG porous plate structures. An efficient numerical differential integral quadrature method (DIQM) is exploited to solve the coupled variable coefficients partial differential equations of equilibrium. Problem validation and verification have been proven with previous prestigious work. Numerical results are illustrated to present the significant impacts of kinematic shear relations, gradation indices through thickness and length, porosity type, and boundary conditions on the static deflection and stress distribution of BDFGP plate. The proposed model is efficient in design and analysis of many applications used in nuclear, mechanical, aerospace, naval, dental, and medical fields.

• Journal of Korean Society on Water Environment
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• v.31 no.5
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• pp.491-506
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• 2015

Distributed models represent watersheds using a network of numerous, uniform calculation units to provide spatially detailed and consistent evaluations across the watershed. However, these models have a disadvantage in general requiring a high computing cost. Semi-distributed models, on the other hand, delineate watersheds using a simplified network of non-uniform calculation units requiring a much lower computing cost than distributed models. Employing a simplified network of non-uniform units, however, semi-distributed models cannot but have limitations in spatially-consistent simulations of hydrogeochemical processes and are often not favoured for such a task as identifying critical source areas within a watershed. Aiming to overcome these shortcomings of both groups of models, a hybrid watershed model STREAM (Spatio-Temporal River-basin Ecohydrology Analysis Model) was developed in this study. Like a distributed model, STREAM divides a watershed into square grid cells of a same size each of which may have a different set of hydrogeochemical parameters reflecting the spatial heterogeneity. Like many semi-distributed models, STREAM groups individual cells of similar hydrogeochemical properties into representative cells for which real computations of the model are carried out. With this hybrid structure, STREAM requires a relatively small computational cost although it still keeps the critical advantage of distributed models.

• Journal of Educational Research in Mathematics
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• v.10 no.2
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• pp.183-197
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• 2000

The purpose of this paper is to present the history of the research in mathematics education, its characteristic and some theories as its results in France. The french research in mathematics education really began with the inauguration of IREM in the institutional aspect, referring to Bachelard in the epistemological aspect and to Piaget in the psychological aspect. It aimed at appreciating the mathematics education as a independent science and focused on the theoretical research through its own object(didactic system) and its own method(didactic engineering). Therefore, it can be characterized by the dense and elaborate theoretical arguments. Consequently, it is known that four major theories in french mathematics education were developed: the theory of didactic situations by trousseau, the theory of didactic transposition by Chevallard, the theory of conceptual fields by Vergnaud, the theory of tool-object dialectic by Douady. Among them, this paper is focused on the situation of institutionalization and the structurization of milieu in the theory of Brousseau and the motive of didactic transposition and the didactic time in the theory of Chevallard. In that the french research in mathematics education has been founded on its own theoretical models, it may contribute to us who envy the basic theories of mathematics education.

• Korean Journal of Health Education and Promotion
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• v.19 no.1
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• pp.149-170
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• 2002

The use of health behavior theory in health counseling may improve its effectiveness. This article provides an overview of health behavior theory and guidelines on how to incorporate various theories into effective health counseling. Models that focus on behavior change at the individual level are described, including the health belief model, which focuses on individual health beliefs; social learning theory, which emphasizes interactions between individual, behavior and its environment; theory of reasoned action and theory of planned behavior, which examines factors influencing behavioral intention;. the stages of change model, which focuses on one's stage of readiness for change. Research review provides explanatory and predictive utility of four health behavior theories. Suggestions for effective health counselling are as follows: 1. Unified theoretical framework incorporating key concepts from different health behavior theories is needed. 2. Need assessment should be included in counselling process. 3. Behavior-change counselling should target changes in one or more key variables previously identified. 4. Focusing on promotional efforts into a high profile behavior(gateway behavior) can be an an adjunctive way of initiating other health promotion behaviors. 5. Counselling should be staged based, and different strategies and processes of changes should be applied at different stages.

• Advances in nano research
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• v.9 no.3
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• pp.157-172
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• 2020

The aim of this present research is the effect of the higher-order terms of the governing equation on the forced longitudinal vibration of a nanorod model and making comparisons of the results with classical nonlocal elasticity theory. For this purpose, the free axial vibration along with forced one under the two various linear and harmonic axial concentrated forces in zigzag Single-Walled Carbon Nanotube (SWCNT) are analyzed dynamically. Three various theories containing the classical theory, which is called Eringen's nonlocal elasticity, along with Rayleigh and Bishop theories (higher-order theories) are established to justify the nonlocal behavior of constitutive relations. The governing equation and the related boundary conditions are derived from Hamilton's principle. The assumed modes method is adopted to solve the equation of motion. For the free axial vibration, the natural frequencies are calculated for the various values of the nonlocal parameter only based on Eringen's theory. The effects of the nonlocal parameter, thickness, length, and ratio of the excitation frequency to the natural frequency over time in dimensional and non-dimensional axial displacements are investigated for the first time.

• Korean Business Review
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• v.1
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• pp.249-271
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• 1987

Applicability of control theories to the efficient operation of accounting system is studied in this paper. Since managerial accounting has been developed along the progrees of control theory, management control theories are essential to explain important attributes of diverse accounting system. Basic concept of control is studied in depth and control systems are classified on the base of their special characteristics. And then the applicability of those control methods to accounting systems are discussed based on behavioral as well as management science approach. In the management science approach, accounting control models of production management, inventory management and R&D are designed with its unique quantitative characteristics. It, however, is very difficult to implement quantified control standards on the behavioral management side. Since most of variables considered on behavioral approach are non-quantitative, only discussion of the theoratical definition has been a main issue on previous studies. In this paper, practicability of the behavioral approach to the accounting control system is studied analyzing state variables and behavior variables of the control system. Theoratical base of the discussion are provided from control theories developed in organization theory and Economics. Basic objective of accounting control practice is to control qualitative human behavior represented by quantified figures while quantitative methods are prevailing over general accounting practice. Therefore, this paper tried to develope and integrate accounting control systems applicable to the behavioral management area as well as management science control side.

• Journal of Digital Contents Society
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• v.18 no.8
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• pp.1677-1684
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• 2017

In this paper, we tried to combine the findings obtained from pedagogical analysis of serious game, which is a study of Soo-Cheol Ha [2, 3], and learning theories such as behaviorism, cognitivism, constructivism, situated learning, and other theories. Based on the previous research, we propose pedagogical elements of serious games based on theories and researches from models and other studies using learning theory. The suggested elements were applied on GSS(Global Startup Simulation), which is a serious game, and the results were confirmed through questionnaire evaluation of learners who are learning through it.

• Structural Engineering and Mechanics
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• v.66 no.4
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• pp.495-504
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• 2018

The current study is dedicated to study the thermal effects of wave propagation in beams, reinforced by carbon nanotubes (CNT). Beams, made up of carbon nanotube reinforced composite (CNTRC) are the future materials in various high tech industries. Herein a Winkler elastic foundation is assumed in order to make the model more realistic. Mostly, CNTs are pervaded in cross section of beam, in various models. So, it is tried to use four of the most profitable reconstructions. The homogenization of elastic and thermal properties such as density, Yong's module, Poisson's ratio and shear module of CNTRC beam, had been done by the demotic rule of mixture to homogenize, which gives appropriate traits in such settlements. To make this investigation, a perfect one, various shear deformation theories had been utilized to show the applicability of this theories, in contrast to their theoretical face. The reigning equation had been derived by extended Hamilton principle and the culminant equation solved analytically by scattering relations for propagation of wave in solid bodies. Results had been verified by preceding studies. It is anticipated that current results can be applicable in future studies.

• Journal of Agricultural Extension & Community Development
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• v.8 no.1
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• pp.85-92
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• 2001

As the technology, global economy, and social structures and patterns have rapidly been changing since the 20th century, the forward-thinking leaders in the world begin to realize that they must embrace a new paradigm in management and organizational theories. The new idea of management is focused on equality rather than hierarchical structure, and more responsive to the external environment, more flexible, and better prepared to give customers what they want. From this new paradigm revolution, the nonprofit organizations like youth development organization are trying to approach and implement the new theories and models. This study attempted to introduce the historical trend and a new paradigm of youth development organizational structures and programs in the USA that may help Korea to improve youth organizations and programs. The youth development sector should create healthy, thriving organizations and structures that cultivate staff, programs, partnership between youth and adults, and community.