• Journal of Korean Society for Quality Management
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• v.49 no.3
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• pp.255-268
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• 2021

Purpose: We sought to understand why a high-speed rotating projectile featuring a fuze-and-body assembly sometimes exhibited airburst, and we intended to improve the flight stability by eliminating airburst. Methods: We performed characteristic factor analysis, structural mechanics modeling, and dynamic modeling and simulation; and we scheduled firing tests to discover the cause of airburst. We used a step-by-step procedure to analyze the reliability function for selecting the bonding force standard that prevents airburst. Results: The 00MM high-speed rotating projectile features a fuze bonded to a body assembly; the bonding sometimes can break on firing. The resulting contact force, vibration and roll damping during flight generated yaw. Flight became unstable; fuze operation triggered an airburst. Our reliability test improved the bonding force standard (the force was increased). When the bonding force was at least the minimum required, a firing test revealed that airburst/flight instability disappeared. Conclusion: Analysis and identification of the causes of flight instability and airburst render military training safer and enhance combat power. Ammunition must perform as designed. Our method can be used to set standards that improve the performances of similar types of ammunition.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.3
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• pp.234-243
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• 2012

In this paper, a sound quality indices for the evaluation of vehicle intake and exhaust noise were developed through a correlation analysis of objective measurement data and subjective evaluation data. At first, intake and exhaust orifice noise were measured at the wide-open throttle sweep condition. And then, acoustic transfer function between intake orifice noise and interior noise at the steady state condition was measured. Also, acoustic transfer function for exhaust system was measured as the same method. Simultaneously, subjective evaluation was carried out by the paired comparison and semantic differential method by 27 engineers. Next, the correlation analysis between the psycho-acoustic parameters derived from the measured data and the subjective evaluation was performed. The most critical factor was determined and the corresponding sound quality index for the intake and exhaust noise was obtained from the multiple factor regression method. At last, the effectiveness of the proposed index was investigated.

• Journal of Korean Medical classics
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• v.19 no.3
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• pp.421-426
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• 2006

Objective To learn if there were different characteristics of tongue demonstration between diseases caused by exogenous pathogenic factor and disorder of internal organs. Methods Choosing 3059 cases from 51 medical records of Qing Dynasty, in which 1397 cases were diagnosed as diseases caused by exogenous pathogenic factor and 1110 were disorder of internal organs. Contrasting the constituent ratio of tongue demonstration using chi-square test. Results There were significant deviation between diseases caused by exogenous pathogenic factor and disorder of internal organs in color of tongue, color of fur and quality of fur (p<0.01). Conclusions the characteristics of tongue demonstration in diseases caused by exogenous pathogenic factor were high frequency of bright red tongue, yellow fur, blank fur and dry fur; and which in disorder of internal organs were high frequency of white tongue, thin fur, greasy fur and exfoliative fur.

• International Journal of Highway Engineering
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• v.16 no.6
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• pp.27-37
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• 2014

PURPOSES : The purpose of this study is to verify the causes of surface scaling at L-shoulder concrete structure. METHODS : From the literature reviews, mechanisms of frost damage were studied and material properties including strength, air void, spacing factor and scaling resistance of L-shoulder concrete structure were analyzed using core specimens taken by real fields. RESULTS : The spacing factor of air void has relatively high correlation of surface conditions : lower spacing factor at good surfacing condition and vice versa. If the compressive strength is high, even thought spacing factor does not reach the threshold value of reasonable durability, the surface scaling resistance shows higher value. Based on these test results, the compressive strength also provide positive effect on the surface scaling resistance. CONCLUSIONS : The main causes of surface scaling of L-shoulder could be summarized as unsuitable aid void amount and poor quality of air void structure. Secondly, although the compressive strength is not the governing factor of durability, but it shows the positive effect on the surface scaling resistance.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.2
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• pp.293-302
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• 2001

The purpose of this study was to investigate the effects of a saleswomans clothing and store type on elderly female consumers likability to a saleswoman. Also it was to study the effects of the factors consisting likability to a saleswoman on intent to purchase among elderly female consumers. 3(clothing formality: low, medium, and high)$\times$2(clothing style: clothing looking old vs. young)$\times$2(store type: high priced specialty store vs. low priced open market) complete randomized between subjects design using field experiments were conducted. Subjects were 240 elderly females aged 54-69. The results showed that likability to a saleswoman consisted of impression factor, service ability factor and caring factor. There was the significant three way interaction among three independent variables in the service ability factor(F(sub)2,228=15.62, P<.001). Regression Analysis showed that the impression factor($R^2$=0.29, F<.001) and the service ability factor($R^2$=0.06, F<.001) influenced the elderly consumers intention to purchase significantly. In conclusion, favorable appearances of a saleswoman is considered a crucial service quality influencing potential elderly consumers to purchase.

• Journal of electromagnetic engineering and science
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• v.16 no.3
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• pp.143-149
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• 2016

This work presents a method used for designing a broadband class-E power amplifier that combines the two techniques of a nonlinear shunt capacitance and a low quality factor of a series resonator. The nonlinear shunt capacitance theory accurately extracts the value of class-E components. In addition, the quality factor of the series resonator was considered to obtain a wide bandwidth for the power amplifiers. The purpose of using this method was to produce a simple topology and a high efficiency, which are two outstanding features of a class-E power amplifier. The experimental results show that a design was created using from a 130 to 180 MHz frequency with a bandwidth of 32% and a peak measured power added efficiency of 84.8%. This prototype uses an MRF282SR1 MOSFET transistor at a 3-W output power level. Furthermore, a summary of the experimental results compared with other high-efficiency articles is provided to validate the advantages of this method.

• Journal of the Korean Society of Costume
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• v.55 no.5 s.95
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• pp.43-54
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• 2005

This study was designed towards female college students to find out how increasing promotional marketing means are affecting the evaluation of clothing products; qualify perception, value perception, and purchase intention. 704 female college students participated in this study and SPSS package was used to analyze gathered data. The results of this study were as follows: First, the use of sales promotional means and preference had a significant difference among students demographic factors(residence, whole Income of the family, allowance, and clothing expenses). Second, qualify perception, value perception, and purchasing intention were the three factors of clothing product evaluation. Third, normal price and $30\%$ sale price clothing was perceived as high quality product and $50\%$ sale price clothing was perceived as high valued product. Purchasing intention was high when low price was suggested or promotional gift was given. Fourth, when considering product price as the factor of product evaluation, there were significant difference between the prices of product. And also, considering the product price, there were significant difference among factors of product evaluation and sales promotional means. Fifth, there was significant correlation between qualify perception, value perception, purchasing intention, usage and preference of promotional means. Further more, value perception was main factor that affected purchasing intention.

• Journal of Magnetics
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• v.16 no.3
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• pp.271-275
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• 2011

This paper proposes a magnetoelectric (ME) composite transducer structure consisting of a magnetostrictive H-type Fe-Ni fork substrate and piezoelectric PZT plates. The fork composite structure has a higher ME voltage coefficient compared to other ME composite structures due to the higher quality (Q) factor. The ME sensitivity of the fork structure reaches 12 V/Oe (i.e., 150 V/cm Oe). The fork composite with two PZT plates electrically connected in series exhibits over 5 times higher ME voltage coefficient than the output of the rectangle structure in the same size. The experiment shows the composite of a Fe-Ni fork substrate and PZT plates has a significantly enhanced ME voltage coefficient and a higher ME sensitivity relative to the prior sandwiched composite laminates. By the use of a lock-in amplifier with 10 nV resolution, this transducer can detect a weak magnetic field of less than $10^{-12}$ T. This transducer can also be designed for a magnetoelectric energy harvester due to its passive high-efficiency ME energy conversion.

• IE interfaces
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• v.20 no.3
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• pp.339-352
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• 2007

Beyond SERVQUAL-based service quality research, we develop a measurement model of public service quality that would provide researchers and practitioners in the public sector with a foundation for systematic investigation and implementation. Firstly, we explore the attributes of public service quality that lead to customer satisfaction by using the critical incident technique (CIT). We identified four dimensions of public service qualities. We also found that the critical attributes of service quality differ according to the types of customers. Secondly, to achieve a high degree of empirical confidence, we conduct statistical tests and analyses on the classification scheme and on the attributes of service quality that we derived from the CIT analysis. Through these analyses, we could remove the redundancy among attributes and group the attributes into new constructs, which are mutually exclusive and exhaustive; we built a more sophisticated measurement model of service quality.

• Journal of Korean Society for Quality Management
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• v.37 no.1
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• pp.56-68
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• 2009

A measure for service quality of university dormitory is developed to gain a better understanding of the quality issues that impact on students' experiences and to improve service quality. Literature survey, thorough discussion with staff members and a pilot test are utilized to elicit attributes of service quality. Factor analysis is used to group the service quality attributes into dimensions. The resulting measure is consisted of 6 dimensions; competence, attitude, facility, amenity, security and discipline. Importance-performance analysis is utilized to verify which factors to be focused on with high Priority to improve dormitory service.