• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.6
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• pp.61-71
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• 2003

In the study of control technique for a turbojet engine model, the Takagi-Sugeno fuzzy logic controller has been designed based on the model identification by the well designed PI controlled system through T-S neuro-fuzzy inference system. To enhance this designed controller, those procedures are proposed that certainty factors are adopted to each rule of objective groups which are classified by the fuzzy C-Means algorithm and the satisfaction degrees are matched to meet the objectives. This proposed technique shows its feasibility by upgrading performances of the previously well-designed T-S fuzzy controller.

• Journal of the Ergonomics Society of Korea
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• v.17 no.1
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• pp.91-102
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• 1998

History of the Sensibility Ergonomics is explained. Concepts, definition, and research methods on the human sensibility are proposed for systematic applications of human sensibility studies to product and environment developments. Sensibility Ergonomics was born in socio-technological environments where consumers required aesthetic and satisfactory products in addition to useful and usable ones, and manufactures were trying to develop consumer-oriented, user-friendly products. Sensibility Ergonomics is defined as "multi-disciplinary and inter-disciplinary processes for developing products and environment as usable, comfortable and satisfactory with the information on human sensibility." Human sensibility is functionally defined as "feelings generated when perceived sensory and information stimuli are reflected from memory which has been accumulated through personal experiences." Human sensibility is affected by at least three factors: personal, social, and cultural. Consumers evaluate products in three aspects : functional, sensorial, and cultural sensibilities. Human sensibility is personal, dynamic, and ambiguous. It is generated reflectively and intuitively against external stimuli. No Physiological responses are accompanied, and one cannot control his/her sensibility. However, the sensibility affects the decision making or behavior of the person. To understand the human sensibility many inter-disciplinary methods should be used instead of one-variable approach. Micro-scopic studies such as Questionnaire, interview, behavioral analysis, and psychophysiological experiments can be performed. In addition, social and cultural studies are essential to understand an individual's sensibility. Results of sensibility studies can be applied to setup new interactions between human and machine through sensible(or affective) human-machine (computer) interfaces. Human-oriented and user-friendly products can be made with the information on human sensibility.

• Korean Journal of Digital Imaging in Medicine
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• v.5 no.1
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• pp.138-149
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• 2002

During the period from may to June 2000, a questionnaire study was carried out on 65 male radiological technologist who had been engaged at VDT work, to find out correlation their symptoms to VDT syndrome factors, work environment and condition. The results were as follows : 1. The mean age was 41.0 years, the mean relay working time was 3.75 hours and the mean duration of using computer monitor was 5.9 years, the satisfactory of working was 44.6% the others 55.4%, among these, 3.1% had symptoms before using the VDT and the others had not. 2. The prevalence of symptoms was the highest on wholebody tired, followed by eye, neck, low back, in decreased order and the lowest was fatique of wrist. 3. There was not significant correlation of symptoms to age, but significant to working time, working duration. 4. There was not significant correlation of symptoms to satisfactory. 5. Working desk, monitor, illuminations, temperature, and noise were significantly related to symptoms. 6. There was significant relation of symptoms to CT, MRI workers.

• Computers and Concrete
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• v.29 no.6
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• pp.433-444
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• 2022

Concrete's compressive strength is widely studied in order to understand many qualities and the grade of the concrete mixture. Conventional civil engineering tests involve time and resources consuming laboratory operations which results in the deterioration of concrete samples. Proposing efficient non-destructive models for the prediction of concrete compressive strength will certainly yield advancements in concrete studies. In this study, the efficiency of using radial basis function neural network (RBFNN) which is not common in this field, is studied for the concrete compressive strength prediction. Complementary studies with back propagation neural network (BPNN), which is commonly used in this field, have also been carried out in order to verify the efficiency of RBFNN for compressive strength prediction. A total of 13 input parameters, including novel ones such as cement's and fly ash's compositional information, have been employed in the prediction models with RBFNN and BPNN since all these parameters are known to influence concrete strength. Three different train: test ratios were tested with both models, while different hidden neurons, epochs, and spread values were introduced to determine the optimum parameters for yielding the best prediction results. Prediction results obtained by RBFNN are observed to yield satisfactory high correlation coefficients and satisfactory low mean square error values when compared to the results in the previous studies, indicating the efficiency of the proposed model.

• Asian Journal of Business Environment
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• v.13 no.4
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• pp.7-17
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• 2023

Purpose: The objective of this study is to evaluate the fringe benefits provided by the entrepreneurs in BSCIC (Bangladesh Small and Cottage Industries Corporation) industrial estates in light of the relevant labor laws of Bangladesh. Research question: Fringe benefits are one of the major factors in compensation that play a vital role in employee satisfaction. However, the issue has yet to be taken into consideration in the industrial units. So, the question arises: what is the present condition of employee fringe benefits in industrial estates? Research design, data, and methods: To conduct this mixed-methods research, a total of 222 respondents were selected randomly from employees and entrepreneurs. Two sets of self-administered questionnaires and KIIs were used to collect primary data, while SPSS was used to analyze the data. Major findings and conclusions: The study shows that the conditions of leave and holidays do not comply with labor laws. Further, aspects of maternity leaves, disability/death benefits, retirement benefits, and other financial and non-financial benefits are found not to be at a satisfactory level and do not comply with the existing labor laws. However, the benefits relating to environmental issues are found to be satisfactory. It is expected that the study findings will contribute to the existing literature related to fringe benefits and will help stakeholders and policymakers in formulating and monitoring compensation packages.

• Journal of Korean Foot and Ankle Society
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• v.5 no.2
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• pp.103-111
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• 2001

Purpose: The purpose of this study was to evaluate prognostic factors of ankle arthroscopy and the effectiveness of high anteromedial and anterolateral portals in diagnosis and treatment for various disease entities. Materials and Methods: The results of ankle arthroscopy were evaluated between March 1992 and January 2000 by one surgeon. Total 169 patients who were followed for a minimum of 12 months, were included in this study. Using high anteromedial and high anterolateral portals, all procedures were done with accessory portals if necessary. A functional evaluation was performed using the Karlsson score and questionnaire subjectively. Results: Fifty-six synovial impingement, 48 osteochondral lesion on talus, 10 impingement exostosis, 8 loose body, 27 osteoarthritis and chondromalacia, 10 postfracture fibrosis, 3 lateral plica, and 1 pigmented villonodular synivitis(PVNS) among 169 patients were diagnosed. Patients with the former four groups had satisfactory results and the latter four groups had not. Remaining 6 patients underwent arthroscopic arthrodesis, and 5 had satisfactory results. Conclusion: Using high anteromedial and anterolateral portals, we could get better visualization of talar dome and posterior chamber of ankle. For better clinical results, in ankle arthroscopy, not only operative skill but also proper indications are important. In case of synovial impingement after trauma, arthroscopy should be considered within one year after initial trauma. There were little correlation between the radiographic findings and arthroscopic findings of articular cartilage in osteochondral lesion of talus, and it is better to determine treatment modality based on the arthroscopic or MRI findings. Osteochondral lesions were treated successfully only when they were traumatically induced and localized without diffuse chondromalacia of talus and tibia.

• Journal of Korean Neurosurgical Society
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• v.29 no.2
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• pp.203-209
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• 2000

Objective : The authors retrospectively analysed the factors affecting the favorable outcomes in the treatment of the Failed Back Surgery Syndrome(FBSS) or six years. Method : From March 1991 to December 1996, seventy-five patients were diagnosed as FBSS and its incidence was 3.4% of admitted patients with back pain in our department. We analysed the demographic data, etiologies, clinical menifestations, outcomes according to methods of operation, numbers of previous surgery, and time intervals between initial operation and final operation. Result : The most common etiology and previous surgical method of FBSS were insufficient surgery(54.7%) and partial laminectomy(53.3%). Patients were managed as followings ; Total laminectomy and spinal fusion with instrument in 41 cases(54.7%), total laminectomy without fusion in 23 cases(30.7%), and only partial laminectomy in 11 cases(14.7%). The overall treatment outcome was satisfactory in 48 cases(64%). Satisfactory results were observed in those patients who were treated by spinal fusion after complete laminectomy(34 cases), who had underwent only one operation previously(45 cases), and when the time interval between the initial operation and reoperation is shorter than 12 months(43 cases). Conclusion : The treatment outcome in FBSS was favorable in cases of the complete total laminectomy and spinal fusion with instrument, only one previous back surgery, and short time interval between initial and final operations.

• Journal of the Korean School Mathematics Society
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• v.9 no.3
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• pp.405-424
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• 2006

The purpose of this study was to develop the instruments which can measure behavior characteristics as a component of Mathematically Giftedness with in middle school period. This study prescribed the variable factors of measurement after classify the characteristics of Mathematically Giftedness through literature studies. And it produced instruments those are finally composed of 51 items through the preliminary test. The participants for the study were 424 Korean middle school students. Statistical analyses were carried out to verify the validities and reliability. Reliability(Cronbach $\alpha$) was in behavior characteristics, .95. Content validity was found to be satisfactory by internal validity evaluation on the test items. Internal validity were analyzed by BIGSTEPTS based on Rasch's 1-parameter item-response model. Construct validity was also found to be satisfactory through factor analysis which showed the four factors which the identification instruments were intended to measure such as, General mathematical mental ability, Mathematical Ability, Processing and Obtaining mathematical information Anility and Mathematical Disposition Ability. In conclusion, the instruments about behavior characteristics of Mathematically Giftedness during middle school period developed by this study are highly reliable on its reliability and validity.

• Journal of the Ergonomics Society of Korea
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• v.29 no.5
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• pp.751-762
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• 2010

The purpose of this study was to investigate the job stress factors of aircraft composite material part manufacturing workers using survey based on 'Job stress factors evaluation tool for Koreans' that was developed by KOSHA in 2003. Two hundred and fifty workers participated in this study, and among them 204 responses were analyzed for this study due to the unreliability and insincerity of responses. The eight job stress factors which are physical environment, job autonomy, job insecurity, organizational system, workplace culture, unfair compensation, relationship conflict, and job requirement were analyzed. The results showed that the stress level of the six job stress factors which are physical environment, job autonomy, job insecurity, organizational system, workplace culture, unfair compensation was relatively higher than that of other industry workers. Generally, all eight job stress factors showed higher stress with temporary workers than with permanent workers, and especially job autonomy, job insecurity, organizational system, and unfair compensation factors showed statistically significant differences (p<0.05). Since the temporary workers are insecure with their job, weak position in organization, having little self-control for the job and lower pay level than that of permanent workers though the job is as same as permanent workers', the stress level of above job stress factors would be much higher than that of the other factors. The group of unsatisfactory with workplace showed higher job stress than group of satisfactory with workplace in all job stress factors, as expected, at the statistically significance level (p<0.05). From the results of this study, the work loss due to the job stress could be prevented, and accurate stress factors could be removed at the workplace. Also the job stress management program can be implemented to improve the work efficiency and the workers' quality of life.

• The Journal of the Acoustical Society of Korea
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• v.27 no.2E
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• pp.35-44
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• 2008

The beat frequency is very important for the sound of Buddhist temple bells, but its concrete origins have not yet been fully clarified. In our research, we considered the beat of the bell at Hojobo Temple (Kanagawa Prefecture). Although its beat frequency has already been measured as 1.6 Hz, no satisfactory explanation has been offered for the factor that determines this value. In our previous research, we investigated the "Doza," the point where the bell is struck, and the "Obi," the vertical stripes around the bell, both of which are circumferential asymmetrical factors that can be visually recognized. Our investigations were carried out by using the Finite Element Method. These factors, however, could not sufficiently explain the beat frequency. Here, we first investigate the "Nyu," the many small projections on the bell, and the deviation between the centers of the inner and outer diameters of the bell. These two factors, however, were also found tobe insufficient explanations of the beat frequency. Through subsequent investigation, however, we finally clarified that the beat frequency's origin lies in the local dimension variation in the "Komazume," which is the bottom part of the bell as well as its thickest part.