• Journal of the Korean Mathematical Society
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• v.51 no.3
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• pp.443-462
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• 2014

Using a simple recurrence relation, we give a new method to compute the Jones polynomials of closed braids: we find a general expansion formula and a rational generating function for the Jones polynomials. The method is used to estimate the degree of the Jones polynomials for some families of braids and to obtain general qualitative results.

• Honam Mathematical Journal
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• v.46 no.1
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• pp.136-145
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• 2024

In this paper we obtained several properties that the characteristic polynomial of the unit-primitive matrix satisfies. In addition, using these properties we have shown that the recurrence relation given as in the formula (1) is true. In fact, Xin and Zhong ([4]) showed it earlier. However, we provide a simpler method here.

• The Mathematical Education
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• v.56 no.4
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• pp.387-405
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• 2017

The purpose of this study is to investigate the change of students 'perception and expression about the motion of object following distance function $={x \atop 3}$ and distance function $y=\frac{x^3}{3}+3$ according to the necessity of research on students' perception and expression about integral constant. In this paper, we present the recognition and the expression of the difference of the constant in the relationship between the distance function and the speed function of the students, while examining the process of constructing the speed function and the inverse process of the distance function. This provides implications for the relationship between the derivative and the indefinite integral corresponding to the inverse process. In particular, in a teaching experiment, a constructive activity was performed to analyze the motion of two distance functions, where the student had a difference of the constant term. At this time, the students used the expression 'starting point' for the constants in the distance function, and the motion was interpreted by using the meaning. This can be seen as a unique 'students' mathematics' in the process of analyzing the motion of objects. These scenes, in introducing the notion of the relation between differential and indefinite integral, it is beyond the comprehension of the integral constant as a computational procedure, so that the learner can understand the meaning of the integral constant in relation to the motion of the object. It is expected that it will be a meaningful basic research on the relationship between differential and integral.

• Journal of Mechanical Science and Technology
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• v.17 no.9
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• pp.1324-1331
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• 2003

A bushing is a device used in automotive suspension systems to cushion the force transmitted from the wheel to the frame of the vehicle. A bushing is essentially a hollow cylinder which is bonded to a solid metal shaft at its inner surface and a metal sleeve at its outer surface. The shaft is connected to the suspension and the sleeve is connected to the frame. The cylinder provides the cushion when it deforms due to relative motion between the shaft and sleeve. The relation between the force applied to the shaft or sleeve and its deformation is nonlinear and exhibits features of viscoelasticity. An explicit force-displacement relation has been introduced for multi-body dynamics simulations. The relation is expressed in terms of a force relaxation function and a method of determination by experiments on bushings has been developed. Solutions allow for comparison between the force-displacement behavior by experiments and that predicted by the proposed method. It is shown that the predictions by the proposed force-displacement relation are in very good agreement with the experimental results.

• The Journal of Korean Physical Therapy
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• v.28 no.1
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• pp.22-26
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• 2016

Purpose: The purpose of this study was to evaluate the relation between PBS scores and GMFCS levels and to examine whether pediatric balance scale (PBS) scores were useful for predicting gross motor functional classification system (GMFCS) levels in children with cerebral palsy. Methods: This cross-sectional study was performed conducted for to evaluatione of PBS and GMFCS using in 26 children with cerebral palsy (16 males and 10 females with GMFCS level I to III). PBS total and item scores at different levels of GMFCS were measured. Results: The hHigh PBS item average scores obtained from standing and postural change dimensions except sitting dimension were observed at the low levels of GMFCS and these results were statistically significant (p<0.05). The relation between PBS (standing and postural change dimensions) and GMFCS levels were was significantly different, except the relation between PBS sitting dimension and GMFCS levels showing a ceiling effect. Conclusion: GMFCS is designed to for classificationy of gross motor functions emphasizing on walking movement and PBS is was developed to for evaluatione of functional balance. Based on the results of this study showing high relation between GMFCS levels and PBS scores, PBS scores can be used for predicting GMFCS levels.

• Nutritional Sciences
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• v.5 no.4
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• pp.211-220
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• 2002

Vitamin C is an essential nutrient involved in many functions. Humans are unable to synthesize vitamin C de novo, because they lack the last enzyme in the biosynthetic pathway. Previous Recommended Dietary Allowances (RDAs) for vitamin C were based on prevention of deficiency with a margin of safety. However preventing deficiency may not be equivalent to ideal nutrient intake. Recommendation should be based on vitamin function in relation to concentration. For this goal, data set of the relationship between wide-range of vitamin C dose and resulting concentrations in plasma and tissues and characterization of functional outcomes in relation to these concentrations should be acquired. This article reviews the current knowledge in these areas and suggest how this knowledge may contribute toward establishing dietary guideline for ideal vitamin C intake.

• Proceedings of the Korean Nutrition Society Conference
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• 2002.11b
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• pp.1157-1168
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• 2002

Vitamin C is an essential nutrient involved in many functions. Humans are unable to synthesize vitamin C de novo, because they lack the last enzyme in the biosynthetic pathway. Previous Recommended Dietary Allowances (RDAs) for vitamin C were based on prevention of deficiency with a margin of safety. However preventing deficiency may not be equivalent to ideal nutrient intake. Recommendation should be based on vitamin function in relation to concentration. For this goal, data set of the relationship between wide-range of vitamin C dose and resulting concentrations in plasma and tissues and characterization of functional outcomes in relation to these concentrations should be acquired. This article reviews the current knowledge in these areas and suggest how this knowledge may contribute toward establishing dietary guideline for ideal vitamin C intake.

• Proceedings of the Korean Nutrition Society Conference
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• 2002.11a
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• pp.54-70
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• 2002

Vitamin C is an essential nutrient involved in many functions. Humans are unable to synthesize vitamin C do novo, because they lack the last enzyme in the biosynthetic pathway. Previous Recommended Dietary Allowances (RDAs) for vitamin C were based on prevention of deficiency with a margin of safety. However preventing deficiency may not be equivalent to ideal nutrient intake. Recommendation should be based on vitamin function in relation to concentration. For this goal, data set of the relationship between wide-range of vitamin C dose and resulting concentrations in plasma and tissues and characterization of functional outcomes in relation to these concentrations should be acquired. This article reviews the current knowledge in these areas and suggest how this knowledge may contribute toward establishing dietary guideline for ideal vitamin C intake.

• Korean Journal of Mathematics
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• v.29 no.4
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• pp.785-800
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• 2021

In this paper, we obtain a new boundary version of the Schwarz lemma for analytic function. We give sharp upper bounds for |f'(0)| and sharp lower bounds for |f'(c)| with c ∈ ∂D = {z : |z| = 1}. Thus we present some new inequalities for analytic functions. Also, we estimate the modulus of the angular derivative of the function f(z) from below according to the second Taylor coefficients of f about z = 0 and z = z₀ ≠ 0. Thanks to these inequalities, we see the relation between |f'(0)| and 𝕽f(0). Similarly, we see the relation between 𝕽f(0) and |f'(c)| for some c ∈ ∂D. The sharpness of these inequalities is also proved.

• Ocean policy research
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• v.34 no.2
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• pp.1-28
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• 2019

The purpose of this study is to analyze the substitution among production factors of Korean distant water longline fisheries in IATTC waters. In the analysis, the translog function which have one output variable of total cost and input variables of labor, fuel, fishing gear, and capital was established and it was transformed into simultaneous equations by each cost. Then, variables of equations were estimated by SUR (seemingly unrelated regression) model. Since distant water longline fisheries is a fishing type with high fuel usage, substitution of fuel with other factors was mainly analyzed. Results showed a substitute relation between fuel and labor as well as fuel and fishing gear, while a complementary relation between fuel and capital. In addition, it was analyzed that magnitude of fuel elasticity with other factors would be inelastic.