• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.763-769
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• 2012

We investigated the width (N) dependence on the magnetization of N-ZSiC NR with electron and hole doping on the basis of systematic DFT calculations. The critical values of the upper and down critical concentration to give the maximum and zero magnetic moment at edge Si/C atoms by electron/hole doping ($x_{up,e}$, $x_{down,e}$, $x_{up,h}$, and $x_{down,h}$) depend on the width of N-ZSiC NR. Moreover, due to $x_{up,e}\;{\neq}\;x_{up,h}$ and $x_{down,e}\;{\neq}\;x_{down,h}$, the electron and hole doping effect are asymmetry, i.e, the critical electron doping value ($x_{down,e}$) is smaller than the critical hole doping value ($x_{down,h}$) and is almost independent of the width of NZSiC NR though the other critical values of the electron and hole doping that influence the magnetization of N-ZSiC NR depend on the width. It was also found that at $x_{down,e}$ or $x_{down,h}$ doping, the N-ZSiC NR turns into unusual non-magnetic metallic state. The magnetic behavior was discussed based on the band structures and projected density of states (PDOS) under the effect of electron/hole doping.

• Journal of applied mathematics & informatics
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• v.38 no.3_4
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• pp.277-290
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• 2020

We propose and analyze a chord summation algorithm, which combines the ideas of Viète and Archimedes to calculate the value of π. The error of the algorithm decreases exponentially per iteration and becomes pinched at a critical iteration, depending on the accuracy of the first input value, ${\sqrt{2}}$. The critical iteration is also analyzed.

• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.2
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• pp.63-79
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• 2002

During the last decade many enterprises spent a huge amount of money for investment on Information Technology (IT) & Information System (IS) to attain competitive advantage and to maximize their business performance by satisfying the various requirements of customers. Under such circumstances, methodologies for evaluating IT impact on business performance are very important issues for strategic decision making on investment. In this study, we propose a performance evaluation model that adopts the concept of the Balanced Scorecard (BSC) and the Value Chain to analyze the financial impact and non-financial impact of IT & IS at each critical work area. This model combines the 4 evaluation areas from BSC and 6 critical work areas from Value Chain and measures the Key Performance Indicator (HPI) and the effect of KPI. Also, we present a case study of which the evaluation model has been conducted on a major manufacturing company. finally. we address some important notes to improve the IT & IS performances in the real-world.

• Journal of the Korean Data and Information Science Society
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• v.16 no.2
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• pp.477-505
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• 2005

This paper gives a computer code that gives p-value's for Kendall's Tau table. The code centers around finding the cumulative frequency of a given Sigma value. Current tables usually give critical values for given cut-off percentages. For small sample sizes the critical values may be inexact, and for large samples the values are not be published. SPSS has a built in function for finding the Kendall rank correlation, but the output does not include the Sigma value. Before the code is given, this paper will concentrate around how to find the Sigma value, and the related tau statistic. The computer code is written in MATLAB, but the ideas can be easily transferred to different languages.

• Progress in Superconductivity and Cryogenics
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• v.12 no.1
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• pp.12-16
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• 2010

Critical current - magnetic field ($I_c$-B) relation is one of the basic properties of an HTS wire, which is needed for the design of performances of superconducting devices. Experimental results of the $I_c$-B relation of Bi-2223 and YBCO superconducting wire are presented in this paper. n-value is also an important parameter which is needed to calculate the electric field by using the power-law. Measurement results of the n-value of the same HTS superconducting wires are also presented.

• Fashion & Textile Research Journal
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• v.21 no.6
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• pp.717-729
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• 2019

This study defines critical fashion designs and investigate its critical messages on fashion itself. The critical messages on fashion are categorized into two major issues of a fashion industry system and fashion consumer culture. This study contributes to the understanding of meaning and value for critical fashion messages that match critical art. As the research method, this study combines a literature review and case studies and the research scope focuses on cases that have appeared in fashion media since the 2000s when social critical messages in fashion began to emerge. The results of the study are as follows. Critical designers such as Viktor & Rolf, Elisa van Joolen, Issey Miyake, and Mary Ping have delivered messages challenging the nature of fashion industry system that criticize the cycle and limitation of a fashion system and pursues changes in perception of sustainability. The critical message on fashion consumer culture articulated by designers such as Alexander McQueen, Vivienne Westwood, Hussein Chalayan, and Ricarda Bigolin & Nella Themelios insist on the formation of community while delivering a critical message on social, political, and cultural problems that raise the mechanism of social awareness through fashion design.

• The Journal of Korean Institute for Practical Engineering Education
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• v.3 no.2
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• pp.53-62
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• 2011

The elliptical trainers(ET) can be a good tool for educating engineers by analyzing physical responses in terms of Respiratory Exchange Ratio (RER, epm) and Heart Rate (HR, bpm). For the various energy expenditure, exercise speed, and weight loss both RER and HR are studied in order to study the blood circulations based on the health training cardiorespiratory. As the results, (1) RER increases gradually as the energy expenditure, however, HR increases gradually up to a critical value and then increases rapidly. The critical value of the energy expenditure in our studies was 275 Cal. (2) RER increases gradually as the ET speed increases, however, HR increases gradually up to a critical value and then increases rapidly. The critical value of the ET speed in our studies was about 6.7km/h. (3) RER increases gradually as the weight loss increases (or, the metabolic cost increases), however, HR is almost nothing to do with the increase of the weight loss.

• Korean Journal of Applied Biomechanics
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• v.16 no.4
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• pp.175-187
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• 2006

The purpose of this study was to find the relationship between Achilles tendon angle, angular velocity from 2D cinematography utilized to easily analyze the functions of shoes, ankle joint moment, knee joint moment, and hip joint moment from 3D cinematography utilized to predict the injury. Also, this study was to provide the optimal standard to analyze the injury related to the shoes. Subjects in this study were 30 university male students and 18 conditions (2 types of running speed, 3 of midsole hardness, 3 of midsole height) were measured using cinematography and force platform. The results were as following. 1) Hip joint abduction moment was effected by many variables such as running speed, midsole height, maximum achilles tendon angle, ground reaction force. 2) Knee joint rotational moment in running was approximately 1/10 - 1/4 times of the injury critical value and eversion moment was approximately 1/4 - 1/2 times of the injury critical value. 3) Ankle joint pronation moment in running was 1/3 - 1/2 times of the injury critical value. 4) Knee joint rotational moment was found to be irrelevant with maximum achilles tendon angle or angular velocity. 5) Pronation from running was thought to be relevant to rather eversion moment activity than rotational moment activity of knee joint. 6) Plantar flexion abductor of ankle showed significant relationship with the ground reaction force variable. 7) When the loading rate for ground reaction force in passive region increased, extensor tended to be exposed to the injury. Main variables in biomechanical analysis of shoes were impact absorption and pronation. Among these variables, pronation factor was reported to be relevant with knee injury from long duration exercise. Achilles tendon angle factor was utilized frequently to evaluate this. However, as the results of this study showed, the relationship between these variables and injury relating variable of knee moment was so important. Studies without consideration on this finding should be reconsidered and reconfirmed.

• The Research Journal of the Costume Culture
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• v.22 no.2
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• pp.346-359
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• 2014

Black Friday, a biggest holiday shopping season in the United States, has been regarded as a great opportunity that fashion retailers can dramatically increase their sales. However, there has been a lack of attention to consumers' shopping experiences on Black Friday from the consumer perspectives. The objective of this study is to explore consumer shopping experiences on Black Friday, in terms of consumer responses toward the experiences, shopping values, and any possible factors influencing the experiences. The method of critical incident technique was used with 198 critical incidents extracted from 165 responses of university students in the United States. As results, the shopping experiences on Black Friday were categorized into positive vs. negative shopping experiences. After that, the positive and negative experiences were respectively divided into two common themes: utilitarian shopping value vs. hedonic shopping value. In addition to the common themes, 12 categories were also emerged. Among positive experiences, utilitarian shopping experiences includes two categories of off-price shopping and shopping for expensive products, whereas hedonic shopping experiences includes three categories of impulse buying, holiday atmosphere, and shopping for the latest or luxury brand products. Among negative experiences, utilitarian shopping experiences includes four categories of modest discounts, out of stock, time-consuming queues, and fatigue of holiday shopping, while hedonic shopping experiences includes three categories of crowded environments, compulsive buying, and poorly managed stores. In conclusion, it is notable that consumer can undergo negative as well as positive shopping experiences on Black Friday. Implications and suggestions are also discussed.

• International Journal of Highway Engineering
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• v.11 no.1
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• pp.69-83
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• 2009

According to the accident statistics of 2006, it can be recognized that drivers' characteristics and driving behaviors are the most causational factors on the traffic accidents. At present, many recording tools such as digital speedometer or black box are distributed in the market to meet social requests of decreasing traffic accidents and increasing safe driving behaviors. However, it is also true that the system preventing any possible vehicle accidents in advance has not been developed. In this study, we developed critical value for deciding dangerous driving behaviors. The developed critical value could be used to contribute to safety driving management systematization and safety driving behaviors.