• Communications of the Korean Mathematical Society
• /
• v.30 no.4
• /
• pp.403-414
• /
• 2015

Extensions of some classical special functions, for example, Beta function B(x, y) and generalized hypergeometric functions $_pF_q$ have been actively investigated and found diverse applications. In recent years, several extensions for B(x, y) and $_pF_q$ have been established by many authors in various ways. Here, we aim to generalize Appell's hypergeometric functions of two variables and Lauricella's hypergeometric function of three variables by using the extended generalized beta type function $B_p^{({\alpha},{\beta};m)}$ (x, y). Then some properties of the extended generalized Appell's hypergeometric functions and Lauricella's hypergeometric functions are investigated.

• The Journal of Information Systems
• /
• v.28 no.2
• /
• pp.109-127
• /
• 2019

Purpose South Korea and China have a long and deep relationship from ancient times to the present. There are many exchanges between economic and educational or other aspects. It will be interesting to compare the perceptions of preliminary entrepreneurs in South Korea and China. Design/methodology/approach This study attempts to analyze the intentions of Korean and Chinese entrepreneurs, and to find the differences between Korean and Chinese entrepreneurs. The research model of this study is composed of internal and external affecting variables, and one dependent variable as the intention of entrepreneurs. A structured questionnaire was distributed to college students and graduate students in South Korea and in China. Data have been analyzed using a Lisrel 8.80 software. Findings The results of this study indicate that all variables except for successful role model have a positive influence on entrepreneurial intentions. The nationality partially mediates the causal relationship between independent variables and dependent variable. Some discussion and implications are suggested.

• Advances in Computational Design
• /
• v.2 no.4
• /
• pp.273-281
• /
• 2017

In this work, a comparative study of multi-objective meta-heuristics (MOMHs) for optimum design of a walking tractor handlebar is conducted in order to reduce the structural mass and increase structural static and dynamic stiffness. The design problem has objective functions as maximising structural natural frequencies, minimising structural mass, bending deflection and torsional deflection with stress constraints. The problem is classified as a many-objective optimisation since there are more than three objectives. Design variables are structural shape and size. Several well established multi-objective optimisers are employed to solve the proposed many-objective optimisation problems of the walking tractor handlebar. The results are compared whereas optimum design solutions of the walking tractor handlebar are illustrated.

• Communications of the Korean Mathematical Society
• /
• v.33 no.2
• /
• pp.473-484
• /
• 2018

In this paper, we discuss how the operational calculus can be exploited to the theory of generalized special functions of many variables and many indices. We obtained the generating relations for 3-index, 3-variable and 1-parameter Hermite polynomials. Some mixed type generating relations and bilateral generating relations of many indices and many variable like Lagurre-Hermite and Hermite-Sister Celine's polynomials are also obtained. Further we generalize some results on old symbolic notations using operational identities.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.19 no.3
• /
• pp.448-462
• /
• 1995

The purpose of this study was on the development of jeans via conjoint analysis and marketing strategies for each segmented market. The questionnaire was composed vervel card and defining the proper marketing strategies for each segmented market. The 269 usable data was distributed to the Univ student and carrier women through multi- stage , ;ambling. The statistical results were processed by the SPSS, PC MDS, and MANZANOLA program. The used methods of statistical data were conjoint analysis, KYST, PROFIT, factor analysis, frequency, one-way ANOVA, SNK, and paired t-test. The results of this study can be summaries as follows: 1. In competitor analysis, Korean brands were in low price zone, but foreign in high price and character style zone. 2. There was significant differences Korean brands and foreign brands on evaluating. On the basis of the perceptual maps, most of Korean brands were evaluated as having a good price and most of foreign brands were evaluated as having a good design. 3. The optimal jeans has the well-known brand, the price of less than 30, 000 won, traditional style, and good quality. In four attributes of clothing buying process, brand is most important attribute of jeans. Segment market 1.All the jeans that they have is Korean brand. Income, amount spent per month on clothing, how many having jeans is low market. Self-centered factor is lowest. In the clothing sari ales lifestyle, they considered most conviniance. Segment market 2-They have one foreign brand jeans. Income, amount spent per month on clothing, how many having jeans is low market. Self-centered factor is lowest Segment market 3-They have two foreign brand jeans. Income, amount spent pet month on clothing, how many having jeans is high market. Self-centered factor is high. In the clothing variables lifestyle, they considered brand, continuance, and character. Segment market 4-They have more than three foreign brand. Income amount spent per month on clothing, and how many having jeans is high market. Self-centered factor is high. In the clothing variables lifestyle, they considered most brand, and character.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.21 no.12
• /
• pp.1063-1070
• /
• 2008

The performance of an acoustic transducer is determined by the effects of many design variables, and mostly the influences of these design variables are not linearly independent of each other. To achieve the optimal performance of an acoustic transducer, we must consider the cross-coupled effects of the design variables. In this study, the variation of the performances of underwater acoustic transducer in relation to its structural variables was analyzed. In addition, the new optimal design scheme of an acoustic transducer that could reflect not only individual but also all the cross-coupled effects of multiple structural variables, and could determine the detailed geometry of the transducer with great efficiency and rapidity was developed. The validation of the new optimal design scheme was verified by applying the optimal structure design of a flextensional transducer which are the most common use for high power underwater acoustic transducer. With the finite element analysis(FEA), we analyzed the variation of the resonance frequency, sound pressure, and working depth of a flextensional transducer in relation to its design variables. Through statistical multiple regression analysis of the results, we derived functional forms of the resonance frequency, sound pressure, and working depth in terms of the design variables. By applying the constrained optimization technique, Sequential Quadratic Programming Method of Phenichny and Danilin(SQP-PD), to the derived function, we designed and verified the optimal structure of the Class IV flextensional transducer that could provide the highest sound pressure level and highest working depth at a given operation frequency of 1 kHz.

• Korean Journal of Construction Engineering and Management
• /
• v.13 no.2
• /
• pp.91-101
• /
• 2012

In planning phase of Public Multi-Housing Projects, it is required to develop the methodology and criteria for fair cost prediction with influencing power from planning phase to occupancy phase. Many studies still have focused on the prediction of cost by multiple regression. However, there is no logical explanation about the influence of nonmetric variables for the prediction of cost in planning phase. Accordingly, this research pursues a cost prediction model including nonmetric variables for use in planning phase. There are 3 steps of this research : 1) Finding the factors influencing construction cost and assigning variables for a multiple regression. 2) Conducting a dummy regression analysis with nonmetric variables and model validation by comparing actual cost data. 3) Developing the ratio of RC structure cost to wall structure cost by using cost predection model. The results could establish cost prediction process including the influence of nonmetric variables and the ratio of RC structure cost to wall structure cost.

• The Journal of Korean Academy of Prosthodontics
• /
• v.43 no.5
• /
• pp.633-649
• /
• 2005

Statement of problem: In spite of the progress in techniques and materials in complete denture prosthodontics, patients still complain of discomfort after the insertion of complete dentures. For the last several decades many prosthodontists tried to find factors influencing patient complete denture satisfaction, however the reported results became a controversy. Purpose: The purpose of the present study was to verify the factors influencing patient satisfaction with complete dentures using multiple regression analysis. Materials and methods: 33 patients who visited the department of prosthodontics, dental hospital of Yonsei University, 4 to 6 weeks after the complete denture delivery, were asked to complete the questionnaires on complete denture satisfaction, social variables and psychological variables. The Prosthodontists who treated the patients with complete dentures were also asked to complete the questionnaires on evaluation of patients' oral condition and technical quality of dentures. The factors influencing patients' satisfaction with their complete dentures were analyzed using multiple regression analysis. Results: Among the patients' sociodemographic variables. the variables of relationship with children, economic status, housing condition, other people's opinions of dentures and gender were the influential factors on patients' satisfaction with complete dentures. Patients showing the symptoms of depression, one of the psychological variables, were dissatisfied with their complete dentures. In spite of the good oral condition, patients were dissatisfied with complete dentures, where-as the technical quality of dentures did not influence patients' complete denture satisfaction. Conclusion : According to the results above, patients' sociodemographic and psychological variables rather than clinical variables including oral condition and technical quality of dentures were the influential factors on complete denture satisfaction. The results of this study may not only enable prosthodontists to predict the success and failure of complete denture treatment, but also help both prosthodontists and patients be informed of the essentials of increasing satisfaction with complete dentures.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.17 no.3
• /
• pp.355-367
• /
• 2007

This paper proposes a design method of the PI(Proportional-Integral)+D(Derivative) controller using self-tuning of the design variables and controller gains. The used fuzzy PI+D controller is the approximated conventional continuos time linear PI+D controller and the used fuzzification method is the fuzzy single tone and the adapted defuzzification method is the simplified tenter of gravity. Fuzzy estimation result would be calculated in the other function elements from the classified fuzzy variables and the result determined by the design variables decides the controller gains. As a result, the proposed method shows the capability of the high speed tuning and can be applied to the case of input variables with many fuzzy partitions and also can bring out the advantage to reduce the reconstruction(digital sampling reconstruction) error. Most simulation results show that this controller makes much bettor efficiency and improvement by using design variables and controller gains.

• Journal of Digital Convergence
• /
• v.17 no.5
• /
• pp.217-223
• /
• 2019

A study in predicting defects of spot welding in real time in automotive field is essential for cost reduction and high quality production. Welding quality is determined by shear strength and the size of the nugget, and results depend on different independent variables. In order to develop the real-time prediction system, multiple regression analyses were conducted and the two dependent variables were obtained with sufficient statistical results with three independent variables, however, the quality prediction by the regression formula could not ensure accuracy. In this study, a multi-layer neural network circuit was constructed. The neural network by 10 dynamic resistance variables was constructed with three hidden layers to obtain execution functions and weighting matrix. In this case, the neural network was established with three independent variables based on regression analysis, as there could be difficulties in real-time control due to too many input variables. As a result, all test data were divided into poor, partial, and modalities. Therefore, a real-time welding quality determination system by three independent variables obtained by multiple regression analysis was completed.