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The Characteristics of Mathematics in Ancient India (고대 인도수학의 특징)

  • Kim, Jong-Myung
    • Journal for History of Mathematics
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    • v.23 no.1
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    • pp.41-52
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    • 2010
  • Ancient Indian mathematical works, all composed in Sanskrit, usually consisted of a section of sturas in which a set of rules or problems were stated with great economy in verse in order to aid memorization by a student. And rules or problems of the mathematics were transmitted both orally and in manuscript form.Indian mathematicians made early contributions to the study of the decimal number system, arithmetic, equations, algebra, geometry and trigonometry. And many Indian mathematicians were appearing one after another in Ancient. This paper is a comparative study of mathematics developments in ancient India and the other ancient civilizations. We have found that the Indian mathematics is quantitative, computational and algorithmic by the principles, but the ancient Greece is axiomatic and deductive mathematics in character. Ancient India and the other ancient civilizations mathematics should be unified to give impetus to further development of mathematics education in future times.

A Study on an Evaluation Method for LCD TV Products Using Axiomatic Design based Hybrid AHP/DEA Model (공리적 설계 기반의 AHP/DEA 혼합모형을 이용한 LCD TV평가방법에 관한 연구)

  • Choi, Min-Soo;Kim, Woo-Je;Cho, Hyun-Ki;Park, Se-Jung
    • Korean Management Science Review
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    • v.29 no.1
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    • pp.33-56
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    • 2012
  • Domestic LCD TV market is composed of two groups of products produced by major firms and small and medium enterprises. The major companies make the price relatively high, but the other makes lower in the same sizes. The model of the low price products does not make consumers choice when they choose LCD TV. This makes the questions of capability between difference price products. The reason above mentioned, the firms that include group of comparatively lower price, are worried about not increasing sale because of prejudice. This study is to find any interrelationship and evaluate the efficiency between the products using performance, exterior and brand power of product. In order to do this, a hybrid AHP/DEA evaluation model for comparison/valuation of LCD TV products is developed. The proposed process is; first, to derive hierarchy structure of LCD TV evaluation criteria using axiomatic design, second, to calculate the score of each LCD TV product through AHP analysis including weight calculation of evaluation criteria, and last, to evaluate the efficiency of LCD TV product by applying DEA by defining product scores as output and prices as input. It concludes that the high price products shows good efficiency, but there are some products with good exterior and brand power, not performance, also presenting good efficiency.

Development of Evaluation Method for Performance of Weapon System using Axiomatic Design based Inner Dependence AHP (공리적설계 기반의 내부종속 AHP를 이용한 국방무기 해외 구매사업의 무기성능 평가방법 개발)

  • Cho, Hyunki;Kim, Woo-Je
    • Korean Management Science Review
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    • v.29 no.3
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    • pp.45-65
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    • 2012
  • Test and evaluation of weapon system is an important task to evaluate the performance of overseas weapon system purchasing project. Especially, quantitative evaluation of performances is hardly completed in defense projects where multiple criteria are conflicted each other. In order to solve this problem, we apply Axiomatic Design (AD) and Inner Dependence AHP method. First, finite functional requirements (FRs) are categorized in hierarchy structure by selecting proper design parameters (DPs) to implement their corresponding FRs. If there are no ways to select DPs when design is coupled between FRs and DPs, then inner dependence is allowed to overcome the strict rule of independence in AHP. Second, the weights of DPs are calculated by applying both Inner Dependence AHP method for coupled design and normal AHP method for uncoupled or decoupled design. Finally, information axiom of AD is applied to the proposed weapon systems by calculating information contents for all parameters. Weapon system with minimum sum of information contents is considered as the best solution. The proposed method in this study should be used in multiple criteria decision making problems involving various conflicting criteria.

The Ethical Values of Nursing Students (간호학생의 윤리적 가치관)

  • Ah, Eun-Kyong;Ku, Ok-Hee;Kim, Tae-Sook
    • Journal of Korean Academy of Nursing Administration
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    • v.4 no.1
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    • pp.19-31
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    • 1998
  • The purpose of this study was to identify whether ethical values of nursing students are deontological or utilitarinian. The subjects of this study were consisted of 163 nursing students. The data was collected from September 3 to 30, 1997. Sub-scale of Nursing Ethical Values(Lee, 1990) were used to measure human life area, nurse-patient relationship area, nurse-nursing task relationship area, nurse-colleague relationship area. Data were analyzed by SPSS for Windows program. The results of this study were summarized as follows: 1. The students took the position of utilitarian slightly in human life area. 2. The students took deontological position slightly in nurse-patient relationships area. 3. The students took deontological position slightly in nurse-nursing task relationships area. 4. The students took deontological position greatly in nurse-colleague relationships area. 5. There were significant relationship between nurse-colleague relationship area and both human life area and nurse-patient relationship area(p< .01). 6. The ethical values of human life area related to religion(p< .01) and attitude of nursing(p< .05). The ethical values of nurse-colleague relationships area related to attitude of nursing(p< .01).

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Optimization of the multi-chamber perforated muffler for the air processing unit of the fuel cell electric vehicle (연료전지 자동차용 흡기 소음기의 설계 변수 최적화에 관한 연구)

  • Kim, Eui-Youl;Kim, Min-Soo;Lee, Sang-Kwon;Seo, Sang-Hoon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2009.04a
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    • pp.342-350
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    • 2009
  • Fuel cells convert a fuel together with oxygen in a highly efficient electrochemical reaction to electricity and water. Since the electrochemical reaction in the fuel cell stack dose not generate any noise, Fuel cell systems are expected to operated much quieter than combustion engines. However, the tonal noise and the broad band noise caused by a centrifugal compressor and an electric motor cause which is required to feed the ambient air to the cathode of the fuel cell stack with high pressure. In this study, the multi-camber perforated muffler is used to reduce noise. We propose optimized muffler model using an axiomatic design method that optimizes the parameters of perforated muffler while keeping the volume of muffler minimized.

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Design Enhancements for Automotive Integrated Shell Structures (차량 복합판형부품의 설계개선 기법들)

  • Lee, Hyeong-Il;Seo, Hyeon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.5 s.176
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    • pp.1103-1114
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    • 2000
  • Recent attempt to enhance the safety against collision reshaped the simple shell structures into the integrated complex shell structures. Moreover, due to various regulations continuously tightened for environment protection, weight reduction of automobiles becomes an increasingly important issue. Auto parts lightening is mainly accomplished by more reasonable design, adoption of lighter materials and miniaturization of the auto bodies. Focusing on the locally enhanced design approach among the above three ways, we here attempt to develop a patching optimization method, and also to determine the thicknesses of an integrated shell structure, both bringing a specified amount of stress relaxation. We first select a cross member as a patching optimization model. Based on the finite element stress calculations, we relieve the stress of cross member by patching in two ways-nonuniform thickness patching and optimized uniform thickness patching, the latter of which is more effective in a practical point of view for the preset amount of stress relaxation. Selecting a box type subframe as another finite element analysis model, we then determine the thickness of each part by axiomatic design approach for a preset amount of stress relaxation. The patching methodology and the axiomatic approach adopted in this work can be applied to the other complex shell structures such as center member and lower control arm.

On the Standard Completeness of an Axiomatic Extension of the Uninorm Logic

  • Yang, Eun-Suk
    • Korean Journal of Logic
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    • v.12 no.2
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    • pp.115-139
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    • 2009
  • This paper investigates an extension of the uninorm (based) logic UL, which is obtained by adding (t-weakening, $W_t$) (($\phi$ & $\psi$) ${\wedge}$ t) $\rightarrow$ $\phi$ to UL introduced by Metcalfe and Montagna in [8]. First, the t-weakening uninorm logic $UL_{Wt}$ (the UL with $W_t$) is introduced. The algebraic structures corresponding to $UL_{Wt}$ is then defined, and its algebraic completeness is established. Next standard completeness (i.e. completeness on the real unit interval [0, 1]) is established for this logic by using Jenei and Montagna-style approach for proving standard completeness in [3, 6].

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A Study on Pick-up Device of Beep Sea Manganese Nodules Collector (심해저 망간단괴 집광기의 채집장치에 관한 연구)

  • Hong, Sub;Sim, Jae-Yong;Lee, Tae-Hee;Choi, Jong-Soo
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.11a
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    • pp.891-895
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    • 1996
  • Performance and efficiency of hybrid (hydraulic-mechanical) pick-up device of deep sea manganese nodules collector are very sensitive to altitude and altitude of pick-up head relative to undulating seafloor. For this reason, motion control of pick-up head relative to the changing deep sea topography and other disturbances is of particular importance in design of pick-up device. The concept of design axiom is applied to a pick-up device of hybrid type. Kinematic analysis conducted in absolute Cartesian coordinates gives position, velocity, and acceleration of the hydraulic cylinders which enable the pick-up head to keep the preset optimal distance from seafloor. Inverse dynamic analysis provides the driving forces of hydraulic cylinders and the reaction forces at each joint. Design sensitivity analysis is performed in order to investigate the effects of possible design variables on the change of the maximum strokes of hydraulic cylinders. The direct differentiation method is used to obtain the design sensitivity coefficients.

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A Study on Geometrical Probability Instruction through Analysis of Bertrand's Paradox (Bertrand's Paradox 의 분석을 통한 기하학적 확률에 관한 연구)

  • Cho, Cha-Mi;Park, Jong-Youll;Kang, Soon-Ja
    • School Mathematics
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    • v.10 no.2
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    • pp.181-197
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    • 2008
  • Bertrand's Paradox is known as a paradox because it produces different solutions when we apply different method. This essay analyzed diverse problem solving methods which result from no clear presenting of 'random chord'. The essay also tried to discover the difference between the mathematical calculation of three problem solvings and physical experiment in the real world. In the process for this, whether geometric statistic teaching related to measurement and integral calculus which is the basic concept of integral geometry is appropriate factor in current education curriculum based on Laplace's classical perspective was prudently discussed with its status.

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Design Evaluation of Pickup Device Collecting Deep-Sea-Manganese Nodules (심해저 망간단괴 집광기 채집장치의 설계평가)

  • Choi, Jong-Soo;Lee, Tae-Hee;Hong, Sub;Sim, Jae-Yong
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.3
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    • pp.68-74
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    • 1998
  • Performance and efficiency of deep seabed collector is a primary factor for feasibility of commercial deep ocean mining. The efficiency of manganese nodules collector depends on vehicle mobility relative to undulating seafloor and is attributed pickup head to keep altitude and elevation of it against seafloor. For this reason, motion control of pickup head relative to the changing deep-sea topography and other disturbances is of particular importance in design of pickup device. The concept of design axiom is applied to a pickup device of hybrid type in order to evaluate the concept design. Kinematic analysis conducted in absolute Cartesian coordinates gives position, velocity, and acceleration of the hydraulic cylinders which enable the pickup head to keep the preset optimal distance from seafloor. Inverse dynamic analysis provides the driving forces of hydraulic cylinders and the reaction forces at each joint. Design sensitivity analysis is performed in order to investigate the effects of possible design variables on the change of the maximum strokes of hydraulic cylinders. The direct differentiation method is used to obtain the design sensitivity coefficients.

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