• Journal of Biomedical Engineering Research
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• v.30 no.3
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• pp.241-246
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• 2009

Since inappropriate muscle forces mean that people cannot perform some activities related to roles of the muscle, muscle forces have been considered as an important parameter in clinic. Therefore, many methods have been introduced to estimate muscle forces indirectly. One of the methods is muscle tissue dynamics and it is widely used in commercial softwares including musculoskeletal model, such as SIMM. They, however, need motion data captured from 3-dimensional motion analysis system. In this study, we introduced an algorithm to estimate muscle forces in real-time by using joint angles. The heel-rise movements were performed for a normal with 3-dimensional motion analysis system, EMG measurement system, and electrogoniometers. Joint angles obtained from electrogoniometers and EMG signals were used to estimate muscle forces. Simulation was performed to find muscle forces using motion data which was imported into musculoskeletal software. As the results, muscle lengths and forces from the developed algorithm were similar to those from commercial software in pattern. Results of this study would be helpful to implement a tool to calculate reasonable muscle forces in real-time.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.5
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• pp.94-100
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• 2003

One of unique characteristics of guided waves is a dispersive behavior that guided wave velocity changes with an excitation frequency and mode. In practical applications of guided wave techniques, it is very important to identify propagating modes in a time-domain waveform for determination of detect location and size. Mode identification can be done by measurement of group velocity in a time-domain waveform. Thus, it is preferred to generate a single or less dispersive mode But, in many cases, it is difficult to distinguish a mode clearly in a time-domain waveform because of superposition of multi modes and mode conversion phenomena. Time-frequency analysis is used as efficient methods to identify modes by presenting wave energy distribution in a time-frequency. In this study, experimental guided wave mode identification is carried out in a steel plate using time-frequency analysis methods such as wavelet transform. The results are compared with theoretically calculated group velocity dispersion own. The results are in good agreement with analytical predictions and show the effectiveness of using the wavelet transform method to identify and measure the amplitudes of individual guided wave modes.

• Therapeutic Science for Rehabilitation
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• v.7 no.2
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• pp.9-16
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• 2018

Objective : The aim of this research was to provide EEG (electroencephalogram) basic data in clinical areas through identifying measurement tools, measurement methods, and evaluation and analysis method of the EEG which is a neurological change measurement of patients with brain injury. Methods : Previous studies were found in an electronic database (e.g., PubMed, Science Direct). The keyword search terms were 'Electroencephalography', 'stroke', 'intervention OR training'. Results : Utilitizing brain-computer interface, the EEG, which is a tool for measuring the effects of rehabilitation through changes of brain activation state. Also, it could identify functional brain reorganization mechanism. Whenever a research utilized the EEG, which is composed of various channels, different types of electrode, and varied electrode locations. Conclusions : Through this review, we found that Electroencephalography is possible to neurologically verify the effectiveness of intervention and formulate an intervention strategy for efficient occupational therapy.

• Composites Research
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• v.27 no.4
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• pp.152-157
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• 2014

Non-destructive testing methods of composite materials are very important for improving material reliability and safety. AE measurement is based on the detection of microscopic surface movements from stress waves in a material during the fracture process. The examination of AE is a useful tool for the sensitive detection and location of active damage in polymer and composite materials. FBG (Fiber Bragg Grating) sensors have attracted much interest owing to the important advantages of optical fiber sensing. Compared to conventional electronic sensors, fiber-optical sensors are known for their high resolution and high accuracy. Furthermore, they offer important advantages such as immunity to electromagnetic interference, and electrically passive operation. In this paper, the crack detection capability of AE (Acoustic Emission) measurement was compared with that of an FBG sensor under tensile testing and buckling test of composite materials. The AE signals of the PVDF sensor were measured and an AE signal analyzer, which had a low pass filter and a resonance filter, was designed and fabricated. Also, the wavelength variation of the FBG sensor was measured and its strain was calculated. Calculated strains were compared with those determined by finite element analysis.

• Korean Medical Education Review
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• v.25 no.3
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• pp.243-257
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• 2023

This study aimed to analyze trends in research on depression among medical students in Korea and to conduct a meta-analysis to determine the average correlation coefficients between depression and related variables. In total, 38 quantitative studies (four theses and 34 journal articles) published between January 1995 and February 2023 were analyzed according to publication year, subjects, analysis methods, and measurement tools. Among them, 15 studies that provided numerical information on the relationships between depression and variables such as self-esteem, social support, grade point average (GPA), stress, and academic stress were selected for meta-analysis. The main findings of this study were as follows. First, quantitative research on depression among medical students began in earnest in 2009, and cross-sectional studies targeting first-year and second-year medical students were the most prevalent. Furthermore, the most commonly used analysis method was difference testing, and the Beck Depression Inventory was the most frequently used measurement tool. Second, the mean correlation coefficients between depression and stress, self-esteem, social support, academic stress, and GPA were 0.534, 0.532, 0.465, 0.390, and 0.102, respectively. The results for self-esteem, stress, and academic stress showed substantial heterogeneity, while those for social support and GPA showed little heterogeneity. These findings suggest that educational interventions, such as social support improvement programs, are necessary to prevent depression among medical students.

• Child Health Nursing Research
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• v.27 no.3
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• pp.201-210
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• 2021

Purpose: This study analyzed research trends related to childhood and adolescent cancer survivors (CACS) using word co-occurrence network analysis on studies registered in the Korean Citation Index (KCI). Methods: This word co-occurrence network analysis study explored major research trends by constructing a network based on relationships between keywords (semantic morphemes) in the abstracts of published articles. Research articles published in the KCI over the past 10 years were collected using the Biblio Data Collector tool included in the NetMiner Program (version 4), using "cancer survivors", "adolescent", and "child" as the main search terms. After pre-processing, analyses were conducted on centrality (degree and eigenvector), cohesion (community), and topic modeling. Results: For centrality, the top 10 keywords included "treatment", "factor", "intervention", "group", "radiotherapy", "health", "risk", "measurement", "outcome", and "quality of life". In terms of cohesion and topic analysis, three categories were identified as the major research trends: "treatment and complications", "adaptation and support needs", and "management and quality of life". Conclusion: The keywords from the three main categories reflected interdisciplinary identification. Many studies on adaptation and support needs were identified in our analysis of nursing literature. Further research on managing and evaluating the quality of life among CACS must also be conducted.

• Journal of the Korean Society of Physical Medicine
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• v.10 no.4
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• pp.81-90
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• 2015

PURPOSE: The purpose of this study was to compare the muscle architecture of serratus anterior and lower trapezius using rehabilitative ultrasound imaging (RUSI) in affected and unaffected side of chronic stroke patients. METHODS: The participants were thirty five patients with stroke hemiplegia in this study. RUSI was used to measure the muscle thickness of the serratus anterior and lower trapezius muscles. We compared the muscle thickness according to affected side and sex, determined the reliability of the measurement image. Independent t-test, intra-class correlation coefficient (ICC) and standard error of measurement (SEM) were used for statistical analysis. RESULTS: Significant difference in muscle thickness of serratus anterior was observed between affected and unaffected side (p<.001). Muscle thickness according to gender showed a significant difference in unaffected side of serratus anterior (p<.05). Compare asymmetry ratio of serratus anterior and lower trapezius muscle thickness showed a significant difference (p<.001). ICC for intra-reliability was .944~.962 in serratus anterior and .873~.925 in lower trapezius muscle thickness, respectively. SEM was .001~.004 in serratus anterior and .002~.008 in lower trapezius muscle. CONCLUSION: This study, using RUSI, showed significant difference in muscle thickness of serratus anterior in affected and unaffected side of stroke patients. RUSI is a practical tool for measuring soft-tissue thickness in the scapular region muscle of stroke.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.3 no.2
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• pp.54-58
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• 2017

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS) is one of the powerful methods that enable analysis of small molecules as well as large molecules up to about 500,000 Da without severe fragmentation. MALDI-TOF MS, thus, has been a very useful an analytical tool for the confirmation of synthetic molecules, probing PTMs, and identifying structures of a given protein. In recent nuclear medicine, MALDI-TOF MS liner ion mode helps researcher calculate the average number of chelator(or linkage) per an antibody conjugate, such as DOTA-(or DFO-) trastuzumab for labeling a medical radioisotope. This simple technique can be utilized to improve the labeling method and control the quality at the development of antibody-based radiopharmaceuticals, which is very effected to diagnosis and therapy for in vivo tumor cells, with radioisotopes like $^{89}Zr$, $^{64}Cu$, and 177Lu. To minimize the error, MALDI-TOF MS measurement is repeatedly performed for each sample in this study, and external calibration is carried out after data collection.

• Journal of Korean Society for Quality Management
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• v.46 no.3
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• pp.607-624
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• 2018

Purpose: The purpose of this study is to present the success of cultural tourism service as visitor loyalty to service and to present the cultural attribute evaluation attribute (HISTOQUAL), experiential flow and tourism satisfaction as determinants effecting loyalty through literature review. Based on this, this study aims to suggest academic and practical implications for revitalizing cultural tourism services and enhancing competitiveness. Methods: This study collects data from visitors to cultural heritage tourist sites and analyzes them empirically. This study conducted a small preliminary sample survey to improve the reliability and validity of the measurement tool, and revised and supplemented the measurement tool on the basis of it. The data collected in this study were analyzed using SPSS 22.0 and the hypothesis was verified through the analysis. Results: The results of this study are as follows; First, the service quality of cultural heritage tourism has a positive effect on the experience flow. Second, the service quality of cultural heritage tourism partially effects tourism satisfaction. Third, it was shown that the experience flow of tourists have a positive effect on tourism satisfaction. Fourth, the experience flow of tourists and tourism satisfaction have a positive effect on loyalty to tourist destination. Conclusion: According to this study, it is the meaning of this study that the cultural tourism service is understood as a attractive factor and based on this, the strategic direction for the activation of cultural tourism service is suggested.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.1
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• pp.94-100
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• 2001

Distortion is a potential problem with all welded fabrication and should be caused dimensional changes and mismatch of joints during welding fabrication. Correction unacceptable weld distortion is extremely costly and in some case impossible. The aim of the present work is to verify the variation of the compressive force, tensile force and distortion during plastic deformation under Tungsten-inert-gas(TIG) welding, on type 304 stainless steel. Experimental results show that possibili-ty if measuring deformation during welding and good correlation was found between analytical and experimental result ad finite element methods have been used to model temperature analysis.