• Journal of IKEEE
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• v.24 no.3
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• pp.754-765
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• 2020

Currently, Intelligent femoral prostheses that support the corresponding mode in walking and specific movements are being studied. Certain controls such as upstairs, sitting, and standing require a technique to classify control commands based on the user's intention because the mode must be changed before the operation. Therefore, in this paper, we propose a technique that can classify various control commands based on the user's intention in the intelligent thigh prosthesis system. If it is determined that the EMG signal needs to be compensated, the proposed technique compensates the EMG signal using the correlation between the strength and frequency components of the normal EMG signal and the muscle volume estimated by the pressure sensor. Through the experiment, it was confirmed that the user's intention was accurately detected even in the situation where muscle fatigue was accumulated. Improved intention detection techniques allow five control modes to be distinguished based on the number of muscle contractions within a given period of time. The results of the experiment confirmed that 97.5% accuracy was achieved through muscle tone compensation even if the strength of the muscle signal was different from normal due to muscle fatigue after exercise.

• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.5
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• pp.365-372
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• 1998

The method of measuring the nonlinear effect of ultrasonic waves is suggested as a new approach for the effective evaluation of material degradation. In sonic wave propagation, the existence of nonlinear effect can be demonstrated by the generation of higher order harmonic waves. So, at first, the mechanism of generating higher order harmonic components due to nonlinear effect was explained by using nonlinear elasticity. Next, we attempted to measure how much of the higher order harmonic component was generated in the degraded material. For this purpose, a measurement system mainly based on a high-powered nonlinear ultrasonic signal analysis system was constructed, and SS41 and SS45 specimen intentionally degraded by tensile load and fatigue load were tested. From the results, we confirmed that the measurement of nonlinear acoustic effect may be useful for the evaluation of material degradation.

• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.6
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• pp.591-597
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• 2001

Ti alloy is used for essential parts of aircraft for high temperature environment. Although Ti alloy has excellent performance in regard to mechanical properties, it is difficult ot find fatigue cracks by nondestructive ultrasonic inspection due to its two-phase microstructure, which consists of hard alpha and beta phases. Sound energy reflected from microstructural features in the component produces a background inspection noise which is seen even when no defects are present. This noise can inhibit the detection of critical internal defects such as pores cracks or inclusions. To obtain fundamental data on ultrasonic inspection of Ti alloy, ultrasonic testing was performed using a specimen with small drill holes and ultrasonic wave propagation velocites were measured.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.6
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• pp.1283-1288
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• 2011

In this paper we collect data concerning sleep environments in a bedroom and analyze the relationship between the collected condition data and sleep. In addition, this paper detects scene changes from the subjects in a sleeping state and presents the physical conditions, reactions during sleep, and physical sensations and stimuli. To detect scene changes in image sequences, we used color histogram for the difference between the preceding frame and the current frame. In addition, to extract the tossing and turning for different situations, the subjects were instructed to enter the level of fatigue, the level of drinking, and the level of stomach emptiness. For the sleep experiment system, we used the H-MOTE2420 Sensor composed of temperature, humidity, and light sensors. This paper is intended to provide the best sleep environment that enhances sleep quality, thus inducing people today to get regular and comfortable sleep.

• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.2
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• pp.163-168
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• 2001

Due to aging, adhesively bonded and riveted aircraft lap joints can contain distends, cracks around rivet holes, fatigue induced flaws, and corrosion. It is required for the safety of aircraft to inspect these defects through the whole region of mint in rapid speed. Bond quality or adhesively bonded and riveted aluminum lap splice joints is investigated using non-contact remote ultrasonic nondestructive evaluation (NDE). Non-contact ultrasonic tests are performed using laser generation and air-coupled transducer detection. A Q-switched Nd:YAG laser and a periodic transmission mask are used to generate a selected Lamb mode. The Lamb wave is generated on one side of the lap splice joint, propagates along the plate, interacts with the joint and is detected on the other side by a micromachined air-coupled capacitance transducer. Analysis of recorded signals allows to evaluate the condition of the bond.

• Journal of Korea Multimedia Society
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• v.7 no.4
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• pp.451-458
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• 2004

A leather quality inspection by naked eyes has known as unreliable because of its biological characteristics like accumulated fatigue caused from an optical illusion and biological phenomenon. Therefore it is necessary to automate the leather quality inspection by computer vision technique. In this paper, we present automatic leather qua1ity classification system get information from leather surface. Leather is usually graded by its information such as texture density, types and distribution of defects. The presented algorithm explain how we analyze leather information like texture density and defects from the gray-level images obtained by digital camera. The density data is computed by its ratio of distribution area, width, and height of Fourier spectrum magnitude. And the defect information of leather surface can be obtained by histogram distribution of pixels which is Windowed from preprocessed images. The information for entire leather could be a standard for grading leather quality. The proposed leather inspection system using machine vision can also be applied to another field to substitute human eye inspection.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3095-3099
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• 2016

Background: Cervical cancer is the most frequently diagnosed cancer among women in India. Understanding quality of life (QOL) in women undergoing chemo-radiotherapy for cervical cancer will help in introducing interventions for better care and outcomes in these women. This study assessed QOL before and after chemo-radiotherapy in cervical cancer patients. Materials and Methods: This follow-up study covered sixty-seven newly diagnosed women with advanced cervical cancer (stages 2b to 4b). Structured questionnaires (the European Organization for Research and Treatment of Cancer, EORTC QLQ-C30 and EORTC QLQ-CX24) were used to assess the change in QOL after 6 months of treatment. Results: The mean age of women at the time of detection of cervical cancer was $52.3{\pm}11.29$ years (Range 30-75 years). Six months survival was 92.53%. The mean global health score of cervical cancer patients after six months of treatment was 59.52, which was significantly higher than the pre-treatment score of 50.15 (p=0.00007). Physical, cognitive and emotional functioning improved significantly (p<0.05) after treatment. Fatigue, pain, insomnia and appetite loss improved but episodes of diarrhea increased after treatment. The mean "symptoms score" using EORTC QLQ-CX24 post treatment was 20.0 which was significantly lower as compared to the pre- treatment score 30.0 (p<0.00001). Sexual enjoyment and sexual functioning decreased significantly after treatment. Conclusions: QOL of newly diagnosed cervical cancer patients improved significantly following chemo-radio therapy. Enhancement was also demonstrated on three of the five functional scales of EORTC QLQ-C30. To further improve QOL, interventions focusing on social and psychological support and physical rehabilitation may be needed.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.6
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• pp.496-503
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• 2016

Leakages at plant structures of power and petrochemistry plants have led to casualties and economic losses. These leakages are caused by fatigue failure of pipelines and their wall thickness. Vibration measurement methods for plant pipelines mainly use acceleration and laser sensors. These sensors are difficult to install and operate and thus lead to an increase in operational cost especially for wide area surveillance. Recently, measurements of leak and vibration displacements using cameras have attracted the interest of many researchers. This method has advantages such as simple installation, long distance monitoring, and wide area surveillance. Therefore, in this paper, we have developed a system that can measure the leakage and vibrational displacement by using a camera. Furthermore, the developed system was verified with experimental data.

• Journal of Korean Public Health Nursing
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• v.33 no.2
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• pp.228-241
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• 2019

Purpose: The purpose of this study was to evaluate the prevalence, awareness, treatment and control of hypertension, diabetes, and dyslipidemia among women with rheumatoid arthritis. Methods: This cross-sectional study of 288 women with rheumatoid arthritis was conducted in a university-affiliated hospital. Data were collected by reviewing the women's medical charts and self-report questionnaires. Results: The prevalence of hypertension, diabetes and dyslipidemia was 27.8%, 5.9% and 48.3%, respectively. Despite the high prevalence of dyslipidemia, the subjects'awareness of it and its treatment rates were the lowest, which resulted in a low control rate. Of the 288 subjects, 158 (55%) had at least one of the three conditions. The prevalence of the combination of cardiovascular risk factors increased with age, and 32.7% of those aged 60 or older had two or three of the cardiovascular risk factors. Combinations of cardiovascular risk factors were significantly related with severe pain and fatigue. Conclusion: Cardiovascular risk factors were highly prevalent among the women with rheumatoid arthritis, but the rates of awareness, treatment, and control were suboptimal. There is a pressing need to facilitate the prevention, early detection and appropriate management of hypertension, diabetes and dyslipidemia among patients with rheumatoid arthritis in order to prevent cardiovascular disease.

• Journal of the Korea Society of Computer and Information
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• v.27 no.5
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• pp.157-163
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• 2022

As the online game market grows, the use of game bots is causing the most serious problem for game services. We propose a harvest coordinate analysis model to detect harvesting bots among game bots of the Massively Multiplayer Online Role-Playing Games(MMORPGs) genre. The proposed model analyzes the player's harvesting behavior using the coordinate data. Game bots can obtain in-game goods and items more easily than normal players and are not affected by realistic restrictions such as sleep time and character manipulation fatigue. As a result, there is a difference in harvesting coordinates between normal players and game bots. We divided the coordinate zones and used these coordinate zone differences to distinguish between game bot players and normal players. We created a dataset with NCSoft's AION log and applied it to a random forest model to detect game bots, and as a result, we derived performance with a recall of 0.72 and a precision of 0.92.