• The Journal of Information Systems
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• v.29 no.1
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• pp.1-22
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• 2020

Purpose Along with increasing use of mobile devices, the sharing economy platform services, which generate profits by sharing products owned or labor, have been activated. A representative example of the sharing economy platform service is Airbnb, which connects providers having idle residential space with users. The results revealed that the cases of superhosts and professional companies had a positive and negative effect on user satisfaction, respectively. Based on signaling theory, this study drew the following implications: residential space providers should make an effort to meet the superhost conditions suggested by Airbnb, and offering residential spaces by individual suppliers rather than professional accommodation companies can more heighten user satisfaction. Design/methodology/approach Because sharing behavior is promoted through trust between interested parties, this study aimed to verify the effects of provider characteristics on user satisfaction in a sharing economy platform service. Specifically, it analyzed user satisfaction, according to host attributes (i.e., "superhost or not," gender, and "professional company or not") among the characteristics of Airbnb suppliers. Findings The results revealed that the cases of superhosts and professional companies had a positive and negative effect on user satisfaction, respectively. Based on these analyses results, this study drew the following implications: residential space providers should make an effort to meet the superhost conditions suggested by Airbnb, and offering residential spaces by individual suppliers rather than professional accommodation companies can more heighten user satisfaction.

• International Journal of Aerospace System Engineering
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• v.2 no.1
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• pp.43-46
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• 2015

Aeroelastic gust response analysis plays an important role in design of aircrafts. For gust response analysis, frequency domain aerodynamics method has been typically used with generalized aerodynamic influence coefficient matrices at various reduced frequencies. However, it cannot be applied to the aeroservoelastic analysis, such as gust alleviation control. Time-domain state space (SS) models must be built. It attacks little attention that gust response analysis relies on continuous gust time-domain input signal in terms of its PSD function. The aim the current study is to provide a reduced-order modeling (ROM) method based on CFD to model gust responses for continuous gust responses for continuou gust inputs in time domain. The paper analyzed the gust response of AGARD445.6 wing subjected to the Dryden gust with ROMs and compared the difference between the rigid structure and elastic one. The results demonstrate that structure elastic effect effect should be considered in the design of aircraft.

• Speech Sciences
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• v.9 no.2
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• pp.89-108
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• 2002

Deaccentuation' means the phenomenon that the accent on the particular element which deserves to be accented, disappears and loses the property of intonational prominence. Based on some theoretical background, we divided the cases where deaccentuation can be placed into six categories : the first, the case that the words already mentioned are repeated in the context; the second, the case that the element can be recovered anaphorically or situationally; the third, the case that the elements are semantically weightless; the fourth, the case that the meaning of the word is empty; the fifth, the case that the elements are less informative, so that they are easy to predict; the sixth, the case that the elements are located after the focused words. Then we organized the context and the experimental sentences corresponding to each category. The utterances of Korean and English native speakers were recorded and analysed based on the ToBI system and compared to each other, in order to find out that Korean speakers can distinguish the difference within each sentence pair, and produce them with appropriate intonation similar to that of native speakers.

• Journal of Korean Institute of Industrial Engineers
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• v.40 no.4
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• pp.404-414
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• 2014

Yield prediction is important to manage semiconductor quality. Many researches with machine learning algorithms such as SVM (support vector machine) are conducted to predict yield precisely. However, yield prediction using SVM is hard because extremely imbalanced and big data are generated by final test procedure in semiconductor manufacturing process. Using SVM algorithm with imbalanced data sometimes cause unnecessary support vectors from major class because of unselected support vectors from minor class. So, decision boundary at target class can be overwhelmed by effect of observations in major class. For this reason, we propose a under-sampling method with minor class based SVM (MCSVM) which overcomes the limitations of ordinary SVM algorithm. MCSVM constructs the model that fixes some of data from minor class as support vectors, and they can be good samples representing the nature of target class. Several experimental studies with using the data sets from UCI and real manufacturing process represent that our proposed method performs better than existing sampling methods.

• Journal of the Korean Wood Science and Technology
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• v.12 no.3
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• pp.3-8
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• 1984

It is shown that Paul and Jones' Rule of Mixtures modified by Smith and Cox's theory can be used for the fiber-reinforced, sulfur-based composites, when the constant for the linear regression equation is given. The computation results, programmed by Hewlett Packard 75C (HP 75C) using math rom pack for the linear regression form, expressed as $E_c=\frac{1}{3}aE_fV_f+bE_mV_m$, turn out to be a=3.27-3.54 b=-2.47~-2.80. This results indicate that the factors such as density of fiber mat and the amount of matrix used have nothing for affecting the numerical value of the constants a and b of the linear regression form. Conclusively this results also show that the Paul and Jones' Rule of Mixtures which has been used for the composites made by randomly-oriented long fiber can also be used for the composites made by short fiber with the same fiber orientation such as wood and lignocellulosic fibers.

• The Journal of the Acoustical Society of Korea
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• v.20 no.6
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• pp.34-39
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• 2001

An adaptive multi-rate (AMR) speech coder was adopted as a standard of W-CDMA by 3GPP and ETSI. The AMR coder is based on the CELP algorithm operating at rates ranging from 12.2 kbps down to 4.75 kbps, and it is a source controlled codec according to the channel error conditions and the traffic loading. In this paper, we implement the DSP S/W of the AMR coder using OakDSPCore. The implementation is based on the CSD17C00A chip developed by C&S Technology, and it is tested using test vectors, for the AMR speech codec, provided by ETSI for the bit exact implementation. The DSP B/W requires 20.6 MIPS for the encoder and 2.7 MIPS for the decoder. Memories required by the Am coder were 21.97 kwords, 6.64 kwords and 15.1 kwords for code, data sections and data ROM, respectively. Also, actual sound input/output test using microphone and speaker demonstrates its proper real-time operation without distortions or delays.

• Journal of the Ergonomics Society of Korea
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• v.35 no.6
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• pp.595-609
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• 2016

Objective: The purpose of this study was to develop and validate the guidelines for Medic Work Table (MWT) based on the anthropometric data of medical technologists. Background: Users' anthropometric data such as sitting height, sitting elbow height, knee height, and so on are significant factors for designing comfortable and useful furniture. Thus, many guidelines for different types of desks and chairs based on the users' anthropometric data have been suggested to many researchers. However, few researches have been conducted to provide design guidelines for MWT for blood collecting task. Medical technologists often use their upper extremities to perform blood collecting task with high repetitions. These repeated motions could be a critical factor in the prevalence rate of Work-related Musculoskeletal Disorders (WMSDs). Therefore, a study on ergonomic design of MWT would be essential in preventing the WMSDs and improving the quality of the working environment of medical technologists. Method: This study suggested design guidelines for ergonomic MWT by focusing on the heights of the upper side and underside, depths of the inside and outside, and width of MWT through anthropometric studies and literature reviews. Afterwards, a new MWT was made using the suggested design guidelines for this study. Five healthy medical technologists participated to evaluate the original MWT and new MWT. All participants took part in the range of motion (ROM) test, electromyography (EMG) muscle activity test, and usability test to validate the suggested guidelines in this study. EMG signals of related muscles (Flexor Carpi Ulnaris, Extensor Carpi Ulnaris, Deltoid Anterior, and Biceps Branchii) were recorded through the surface electromyography system from both the original MWT and the new MWT. The ROM test of the shoulder and elbow flexion was also assessed using motion sensors. Results: The newly designed MWT showed decreased ROMs of the shoulder and elbow up to 22% and 18% compared to the original MWT. The muscle activities in the new MWT also showed a decrease of 13% in Anterior Deltoid, 6% in Biceps Brachii, 5% in Flexor Carpi Ulnaris, and 8% in Extensor Carpi Ulnaris muscle groups, compared to the original MWT. In the usability test, the satisfaction score of the new MWT was also 56.1% higher than that of the original MWT. Conclusion: This study suggested guidelines for designing MWT and validating the guidelines through qualitative and quantitative analyses. The results of motion analysis, muscle activity, and usability tests demonstrated that the newly designed MWT may lead to less physical stress, less awkward posture, and better physical user interface. Application: The recommended guidelines of the MWT would be helpful information for designing an ergonomic MWT that reduces physical loads and improves the performance of many medical technologists.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4411-4417
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• 2012

The present study proposes the optimization of wing structure base on reduced model which assures the solution accuracy and computational efficiency. Well-constructed reduced model assures the accurate result in the eigenvalue problem, dynamic analysis or sensitivity of design optimization. Reduced system is classified into the reduce-order model based on structural modes and the reduced system based on degrees of freedom. Because this study uses the reduced system based on degrees of freedom, it is important to select the dominant degrees of freedom properly. For this work, robust selection method, two-level selection scheme, is employed and IRS(Improved Reduced System) is applied to construct the final reduced system. In the optimization process based on the reduced system, all of the equivalent stress, eigenvalue and design sensitivities are calculated from the reduced system. Through a numerical example, it is shown that the present optimization methodology based on the reduction method can provide an optimal results for objective function satisfying constraint condition.

• Journal of Life Science
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• v.16 no.4
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• pp.584-588
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• 2006

Physical activity has been effective in enhancing quality of life and physical fitness of older adults over relatively short periods of time. However, little is known about the Yoga-based exercise program on physiological changes and physical fitness with psychological variables in elderly women. The purpose of this study is to investigate the effect of Yoga- based exercise program on physiological, psychological factors and physical fitness in elderly women. Forty-four elders were recruited from the public health center. They were divided into exercise training group(n=22) and control group(n=22). The training group participating in 10 weeks of Yoga-based exercise program. Data was analyzed with descriptive statistics, the chi-square test, Fisher's Extract test, and ANCOVA to evaluate body fat, spine ROM, blood pressure, cholesterol, depression, life satisfaction, ADL and physical fitness. There was a significant improvement in blood pressure, total cholesterol, precent of body fat, physiological function, depression, life satisfaction, ADL and physical fitness in the exercise training group than that of the control group. From the results, Yoga-based interventions designed to improve various variables were equally acceptable to elderly women.

• Journal of Families and Better Life
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• v.31 no.1
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• pp.11-27
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• 2013

The purpose of this study was to investigate the overall developmental characteristics of Korean children ages 0 to 8, and then explore specifically how children's social and emotional developmental levels are related to mothers' psychological states. This study was part of newly launched Boryung Baby Panel Study using web-based survey in 2011. The subjects were all mothers of 940 infants(0-2 years), 654 toddlers(3-5 years), and 484 school-age children(6-8 years) The mothers were asked to administer the web-based standardized developmental checklist for their child and fill out the questionnaires of psychological variables(life satisfaction, depression, parenting attitude, parenting efficacy, and parenting stress). The data was analyzed using descriptive analysis, t-test, and logistic regression for SPSS 20.0 windows. Major findings were as follows: 1. Infants(0 to 2) showed higher developmental level in cognition and fine motor skill domain compared to other domains. 2. Most toddlers(3 to 5) showed normal development in the most domain such as gross motor skill, fine motor skill, language, letter, number, self-help behavior. 3. In socio-emotional development domain, the ratio of risk or delay group were highest at both infant and toddler. 4. The 6-8 years old children that belong to risk group by the result of SDQ(emotion and behavior assessment) were also relatively high. 5. The relation of the children's socio-emotional developmental level and the mother's psychological variables were reciprocal. Based on these findings, the implications and the limitations of current study were discussed.