• Title/Summary/Keyword: higher order performance

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Perceived Risk, Satisfaction, and Intention on Rental Clothing (의류 임대시 위험지각, 만족도 및 임대의도)

  • 김용숙
    • Journal of the Korean Society of Costume
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    • v.53 no.7
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    • pp.29-36
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    • 2003
  • The purposes of this syudy were to identify the factors of perceived risk, satisfaction, and intention on rental clothing. The subjects were 767 adults residing in Jeonbuk province. The research was made from February 20 to March 19, 2003. Fof data analysis. frequencies, percentages, mean, and standard deviations were calculated. Also, factor analysis and stepwise multiple-regression analysis were done. The results were as follows: 1. Approximately half of the respondents had experiences of rental clothing, and the most frequent items were wedding dress, degree gown, performance dress, and sports wear in descending order. 2. The factors of perceived risk of rental clothing were divided into lost, appropriateness, and damage, and total variance was 62.51%. The perceived risk about damage of rental clothing was the highest, and lost was the lowest. 3. The factors of rental clothing satisfaction were divided into appearances, store status, function, and fitness, and total variance was 59.96%. The satisfaction of function of rental clothing was the highest, and the store status was the lowest. 4. The intention on rental clothing was high in case of higher interest in rental clothing, higher educational level. more experiences in rental clothing, lower perceived risk of damage on the rental clothing, and younger person, and these variables explained 54.00% of the intention on rental clothing.

Numerical study on Wells turbine with penetrating blade tip treatments for wave energy conversion

  • Cui, Ying;Hyun, Beom-Soo
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.8 no.5
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    • pp.456-465
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    • 2016
  • In order to optimize the performance of a Wells turbine with fixed guide vanes, the designs of an end plate and a ring on the tip of the turbine rotor are proposed as penetrating blade tip treatments. In this study, numerical investigations are made using computational fluid dynamics (CFD)-based ANSYS Fluent software, and validated by corresponding experimental data. The flow fields are analyzed and non-dimensional coefficients $C_A$, $C_T$ and ${\eta}$ are calculated under steady-state conditions. Numerical results show that the stalling phenomenon on a ring-type Wells turbine occurs at a flow coefficient of ${\phi}=0.36$, and its peak efficiency can reach 0.54, which is 16% higher than that of an unmodified turbine and 9% higher than in the case of an endplate-type turbine. In addition, quasi-steady analysis is used to calculate the mean efficiency and output work of a wave cycle under sinusoidal flow conditions. As a result, it has been found that the ring-type turbine is superior to other types of Wells turbines.

Study on the liquefaction performance characteristic of $CO_2$ liquefaction cycle ($CO_2$ 액화 사이클의 액화 성능 특성에 관한 연구)

  • Song, Chan-Ho;Lee, Kong-Hoon
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.1312-1316
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    • 2009
  • Growing interest in $CO_2$ capturing from industrial processes and storage in underground formations is emerging from commitments in reducing $CO_2$ emissions manifested in the Kyoto Protocol. In this paper, $CO_2$ liquefaction system is treated in focus of liquefaction efficiency & production rate. Presently $CO_2$ is transported in ships or trucks at a pressure of 14-20 bar. Considering this, the liquefaction pressures of 20, 15, 6.5 bar are selected. Compressor work and cooling capacity are calculated and compared. In order to investigate the effect of intercooling, the compressed gas after compressor work is cooled by ambient air or seawater. In case of applying the intercooling to the system, consuming energy can be saved larger than 20%. In the lower liquefaction pressure, the more $CO_2$ can be obtained due to higher density. In the liquefaction pressure of 6.5 bar, its $CO_2$ production is about 35% higher than that of the system with the liquefaction pressure, 20 bar.

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Automatic Method for Contrast Enhancement of Natural Color Images

  • Lal, Shyam;Narasimhadhan, A. V.;Kumar, Rahul
    • Journal of Electrical Engineering and Technology
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    • v.10 no.3
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    • pp.1233-1243
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    • 2015
  • The contrast enhancement is great challenge in the image processing when images are suffering from poor contrast problem. Therefore, in order to overcome this problem an automatic method is proposed for contrast enhancement of natural color images. The proposed method consist of two stages: in first stage lightness component in YIQ color space is normalized by sigmoid function after the adaptive histogram equalization is applied on Y component and in second stage automatic color contrast enhancement algorithm is applied on output of the first stage. The proposed algorithm is tested on different NASA color images, hyperspectral color images and other types of natural color images. The performance of proposed algorithm is evaluated and compared with the other existing contrast enhancement algorithms in terms of colorfulness metric and color enhancement factor. The higher values of colorfulness metric and color enhancement factor imply that the visual quality of the enhanced image is good. Simulation results demonstrate that proposed algorithm provides higher values of colorfulness metric and color enhancement factor as compared to other existing contrast enhancement algorithms. The proposed algorithm also provides better visual enhancement results as compared with the other existing contrast enhancement algorithms.

The Effects of Age and Information Processing Style on Abilities of Young Children to Understand Spatial Coordinates (유아의 정보처리양식과 연령이 공간좌표인식능력에 미치는 영향)

  • Oh, Mee-Hyeong
    • Journal of the Korean Home Economics Association
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    • v.46 no.9
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    • pp.125-135
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    • 2008
  • The purpose of this study was to examine the effects of young children's age and information processing style in understanding spatial coordinates. For sampling the subjects of this study, Korean version K-ABC Intelligence Test(Moon, Soo-Back, 1997)was conducted with 165 children aged 5-6 who were attending I and G kindergarten in D city. From this pool 30 children who possessed sequential processing style and 30 children who possessed simultaneous processing style were sampled. In order to analyze the understanding of spatial coordinates, a test tool was formulated according to methodology of Blades & Spencer(1989) which was modified. Acquired data was subjected to descriptive and comparative statistical analysis. The following conclusions were arrived at: Firstly, there was significant difference between 5-year-olds and 6-year-olds in understanding spatial coordinates. The 6-year-old group got statistically higher grades than the 5-year-old group in locating a point on the coordinate plane and reading the coordinate numbers. Secondly, there was significant difference between children's information processing style in understanding spatial coordinate. Children with high simultaneous-low sequential processing showed higher performance in locating a point on the coordinate plane and reading coordinate numbers than children with high sequential-low simultaneous processing. Thirdly, after verifying statistical significance of interactivity between young children's age and children's processing strength, there was significant interactive effects in both tasks.

Fuzzy Logic Based Sound Source Localization System Using Sound Strength in the Underground Parking Lot (지하주차장에서 음의 세기를 이용한 퍼지로직 기반 음원 위치추정 시스템)

  • Choi, Chang Yong;Lee, Dong Myung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.5
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    • pp.434-439
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    • 2013
  • It is very difficult to monitor the blind spots that are not recognized by traditional surveillance camera (CCTV) systems, and the surveillance efficiencies are very low though many accidents/events can be solved by the systems. In this paper, the fuzzy logic based sound source localization system using sound strength in the underground parking lot is suggested and the performance of the system is analyzed in order to enhance the stabilization and the accuracy of the localization algorithm in the suggested system. It is confirmed that the localization stabilization of the localization algorithm (SLA_fuzzy) using the fuzzy logic in the suggested system is 4 times higher than that of the conventional localization algorithm (SLA). In addition to this, the localization accuracy of the SLA_fuzzy in the suggested system is 29% higher than that of the SLA.

The Relationship between Course Grades and the K-CESA Core Competencies for Engineering Students (공학계열 대학생들의 교과목 성적과 K-CESA 핵심역량의 관계 분석)

  • Hwang, Jiwon;Kim, Hakjin;Song, Ohsung
    • Journal of Engineering Education Research
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    • v.19 no.4
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    • pp.35-46
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    • 2016
  • With the emphasis on core competencies, the University of Seoul has exerted efforts to reflect the importance of core competencies in university curricula. The main assessment tool used in Korea is the Korea Collegiate Essential Skills Assessment (K-CESA), developed by the Korea Research Institute for Vocational Education and Training (KRIVET). This study examined whether core competencies measured using K-CESA are valid as a tool for assessing educational achievements among college students, and analyzed the correlation between K-CESA scores and course grades. The analysis was performed on approximately 204 engineering students at the University of Seoul. According to the correlation analysis between core competencies and courses, MSC courses were shown to be related to the resource and through information use competency and higher order thinking competency. Through the Analysis of Variance, students in the accreditation programs and students living in urban area showed higher competency scores. In the multiple regression, it was shown that Accreditation and MSC courses grades were the important variables to predict the competency of the students. Based on these findings, we confirmed that the K-CESA tool has a certain level of correlation with academic performance and that it functions as one of several ways to evaluate the program outcomes of engineering education accreditation.

Solid-Phase Extraction of Curcuminoid from Turmeric Using Physical Process Method (물리적 가공법을 이용한 강황으로부터 Curcuminoid의 고체상추출)

  • Lee, Kwang-Jin;Yang, Hye-Jin;Jeong, Sang-Won;Ma, Jin-Yeul
    • Korean Journal of Pharmacognosy
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    • v.43 no.3
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    • pp.250-256
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    • 2012
  • In order to extract the curcuminoid such as curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC) in turmeric (Curcuma longa), solvent extraction methods (dipping and ultrasonic extraction method) and solid-phase extraction (SPE) were used. RP-HPLC (reverse-phase high-performance liquid chromatography) and TLC (thin-layer chromatography) were used for identification and analysis the three curcuminoid. From the experimental results, it is evident that the percentage of curcuminoid extracted from turmeric by ultrasonic extraction method was higher than dipping method. The percentage of curcumin extracted from turmeric by pure methanol was higher than any aqueous methanolic composition. Moreover, the total peak area of three curcuminoid was above 92% in RP-HPLC using solid-phase extraction. These results will form a database for investigating the constituents of natural products and the resources of pharmaceutical, nutrition, and cosmetic products.

DEVELOPMENT OF RPS TRIP LOGIC BASED ON PLD TECHNOLOGY

  • Choi, Jong-Gyun;Lee, Dong-Young
    • Nuclear Engineering and Technology
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    • v.44 no.6
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    • pp.697-708
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    • 2012
  • The majority of instrumentation and control (I&C) systems in today's nuclear power plants (NPPs) are based on analog technology. Thus, most existing I&C systems now face obsolescence problems. Existing NPPs have difficulty in repairing and replacing devices and boards during maintenance because manufacturers no longer produce the analog devices and boards used in the implemented I&C systems. Therefore, existing NPPs are replacing the obsolete analog I&C systems with advanced digital systems. New NPPs are also adopting digital I&C systems because the economic efficiencies and usability of the systems are higher than the analog I&C systems. Digital I&C systems are based on two technologies: a microprocessor based system in which software programs manage the required functions and a programmable logic device (PLD) based system in which programmable logic devices, such as field programmable gate arrays, manage the required functions. PLD based systems provide higher levels of performance compared with microprocessor based systems because PLD systems can process the data in parallel while microprocessor based systems process the data sequentially. In this research, a bistable trip logic in a reactor protection system (RPS) was developed using very high speed integrated circuits hardware description language (VHDL), which is a hardware description language used in electronic design to describe the behavior of the digital system. Functional verifications were also performed in order to verify that the bistable trip logic was designed correctly and satisfied the required specifications. For the functional verification, a random testing technique was adopted to generate test inputs for the bistable trip logic.

An Experimental Study on the Cooling Characteristics of the Liquid Cooling Radiator of the Natural Convection Type by Using the PCM (PCM을 적용한 자연대류형 수냉식 방열기의 냉각특성에 관한 실험적 연구)

  • Sung, Dae-Hoon;Kim, Joung-Ha;Yun, Jae-Ho;Kim, Woo-Seung;Peck, Jong-Hyeon
    • Proceedings of the SAREK Conference
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    • 2008.11a
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    • pp.324-329
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    • 2008
  • The liquid cooling effect of a natural convection type radiator by using the PCM has been investigated experimentally. The radiator size is $423{\times}295{\times}83$ mm and PCM container size is $398{\times}270{\times}26$ mm. The objective is elapsed time higher than maximum time to reach for maximum operating temperature of a general liquid cooling radiator. This study, in order to study on the effects of the phase-change phenomenon, carried out the various mass flow rate, input electric power, ambient and melting point of three type PCM. For the above experimental parameter, the melting time was performed about 180/250/560 min at input power 150 W and ambient $30^{\circ}C$ from using the three type PCM(PCM_S1/S2/S3) respectively. Furthermore, the effects of the thermal dissipation was decreased higher input power than lower input power at heating block and melting time of PCM. However, the effects of mass flow rate did not nearly affect of the thermal performance especially.

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