• Journal of rehabilitation welfare engineering & assistive technology
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• v.6 no.2
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• pp.31-41
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• 2012

The combination of developed medical devices and the convergence of IT fusion technologies, health variables became to can be measured without discomfort in everyday life regardless of wherever and whenever. because various types of u-Health medical devices have been developed. Also, by considering the users, biological signals can be measured without difference with wearing general clothing, that conductive fabric is being used as smart clothing. However, considering that there is a growing prevalence of the devices and a great interest in the development of u-Health devices, it is urgent to establish performance evaluation. Accordingly, writing guidelines by force to raise checking before marketed or collecting checks after at the market for standard test methods for evaluating the performance. In this paper, it was studied that the possibility of using conductive fabric as electrodes for Wearable u-Health Devices through the material test of the ffabric.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.5
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• pp.653-660
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• 2010

The stern tube bearing is installed to the stern tube and stern boss casting by using the method of the force pressured fitting. The adequate value of the interference between the stern tube bearing and casting should be considered owing to the slip. In this study, to review and compare the fitting force and the contact pressure, the theory of thick walled cylinder is considered to clarify the formula which received from the maker. Also the fitting force and contact pressure are calculated by using the standard value of interference, Young's modulus, Poisson's ratio and friction coefficient.

• Journal of the Korean Geotechnical Society
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• v.29 no.12
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• pp.105-111
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• 2013

The standard penetration test (SPT) has been widely used because of its usability, economy, and many correlations with soil properties among other factors. In SPT, hammer energy is an important factor to evaluate and calibrate N values. To measure hammer energy, an instrumented SPT rod was developed considering that stress waves transferring on rods during SPT driving are the same as stress waves transferring on piles due to pile driving. Using this idea, an instrumented SPT rod with a pile driving analyzer was applied as a pile capacity prediction tool in this study. In order to evaluate this method, SPT and dynamic cone tests with the instrumented SPT rod were conducted and also 2 pile load tests were performed on pre-bored steel pipe piles at the same test site. End bearings were predicted by CAPWAP analysis on force and velocity waves from dynamic cone penetration tests and SPT. Comparing these predicted end bearings with static pile load tests, a new prediction method of the end bearing capacity using the instrumented SPT rod was proposed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.3
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• pp.361-374
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• 2016

The material property of the rubber has been studied in order to improve the reliability of the finite element model of a lead rubber bearing (LRB) which is a typical base isolator. Rubber exhibits elastic behaviour even within the large strain range, unlike the general structural material, and has a hyper-elastic characteristics that shows non-linear relationship between load and deformation. This study represents the mechanical characteristics of the rubber by strain energy function in order to develop a finite element (FE) model of LRB. For the study, several strain energy functions were selected and mechanical properties of the rubber were estimated with the energy functions. A finite element model of LRB has been developed by using material properties of rubber and lead which were identified by stress tests. This study estimated the horizontal and vertical force-displacement relationship with the FE model. The adequacy of the FE model was validated by comparing the analytical results with the experimental data.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.2
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• pp.1-8
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• 2014

The present study proposes a simple equation to straightforwardly determine the potential plastic hinge length in boundary element of reinforced concrete shear walls. From the idealized curvature distribution along the shear wall length, a basic formula was derived as a function of yielding moment, maximum moment, and additional moment owing to diagonal tensile crack. Yielding moment and maximum moment capacities of shear wall were calculated on the basis of compatability of strain and equilibrium equation of internal forces. The development of a diagonal tensile crack at web was examined from the shear transfer capacity of concrete specified in ACI 318-11 provision and then the additional moment was calculated using the truss mechanism along the crack proposed by Park and Paulay. The moment capacities were simplified from an extensive parametric study; as a result, the equivalent plastic hinge length of shear walls could be formulated using indices of longitudinal tensile reinforcement at the boundary element, vertical reinforcement at web, and applied axial load. The proposed equation predicted accurately the measured plastic hinge length, providing that the mean and standard deviation of ratios between predictions and experiments are 1.019 and 0.102, respectively.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.618-624
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• 1988

This study was conducted to observe the effects of partial replacement of mungbean starch(MB) with dent(DT) or cross-linked(CL) corn starches, and of added hydrocolloids on the characteristics of mungbean starch and the mook. The replacement with CL caused less changes compared to that with DT in phase transition enthalpy of MB measured with defferential scanning calorimeter. The viscosity of MB paste cooled to $50^{\circ}C$ after heating was also affected less with CL than with DT. The addition of hydrocolloids to mixed starches of MB and CL did not affect initial viscosity increase but resulted in marked increase in viscosity at later stage of heating. Mixed monks with CL were more similar to MB monks than those with DT. Hydrocolloids added to MB-CL mixture further decreased the gap between monks with and without CL.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.4
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• pp.339-344
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• 2007

Safety of large scale cable in bridge is very important because it may cause the unwanted catastrophic failure. Although the proof load were considered at the design stage, its soundness must be monitored continuously because the cable may be broken out without warning by the variable external load. The cable tension of in-use structures has been mainly measured by the resonance method and its use has been limited because of relatively large measurement uncertainty. Recently a new magnetic method was developed and its reliability is known to be good for evaluating the cable tension. In this study a system which can deliver the calibrated load to the cable was developed and the measurement reliability of developed magnetic sensor according to the change of external load was analyzed quantitatively. The effect of magnetization frequency, bias magnetic field, and temperature on the sensor output was also evaluated.

• Journal of Korean Home Economics Education Association
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• v.18 no.1 s.39
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• pp.31-47
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• 2006

This study developed practical reasoning teaching-learning material for middle school home economics education and tested its effects on middle school students' self-esteem The type of this study was a quasi-experimental research and its independent variable was practical reasoning instruction and its dependent variable was self-esteem. The research design for this study was a pretest-posttest design. Practical reasoning instruction was given for experimental group whereas traditional instruction was given to comparison group. For measuring self-esteem, 'self-esteem scale' developed by Choi & Jun(1993) was used and its Cronbach'a was ranged from .69 to .84. Statistic analysis was done by mean and standard deviation for general characteristics of samples and paired t-test for testing difference of pretest-posttest. The results of this study showed that practical reasoning instruction improved middles school students' self-esteem, the general self-esteem and social self-esteem among sub-areas of self-esteem in particular.

• The korean journal of orthodontics
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• v.33 no.6 s.101
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• pp.465-474
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• 2003

The great variety of commercial brands of orthodontic wires available on the market, stimulated by the so called superior wires (nickel titanium with shape memory effect and superelastic nickel titanium), makes the professional choice for a suitable and less expensive material difficult. The in vitro study of the mechanical properties of the orthodontic wires acts as an auxiliary tool for the professional. In this paper, a comparative study of mechanical properties was made, using stress strain tests for 4 types of orthodontic wires (conventional stainless steel, multistranded steel, superelastic nickel titanium and thermoactivated nickel titanium) separated into 5 groups. A series of 6 tests were tested for each group of wires. Initially, each group was tested 3 times until the wires broke. Furthermore, 3 more tests for each group were performed, stretching the wires under standardized activation loads, for a reliable comparison of their mechanical properties, during loading and unloading. 1 tests were applied to check differences among the groups. In vitro, the results suggest that regarding the mechanical properties supposedly desirable for physiological teeth movement, such as resilience, elasticity modulus, strength liberated during unloading, and the way that strength is liberated, thermoactivated nickel titanium wires, acting under mouth temperature, seems to be a good choice, fellowed by superelastic nickel titanium, multistranded stainless steel, and conventional stainless sleet. Superelasticity was demonstrated for superelastic nickel titanium wires. When at $37^{\circ}C$, thermoactivated nickel titanium wires showed shape memory effect, showing that temperature is important for enhancing the mechanical properties.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.419-427
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• 2020

This study was undertaken to address the difficulties and inconveniences of an electric wheelchair. We focused on improving usability of initially completed products by augmenting the prototypes designed in the previous study. For evaluation of usability, 10 elderly women aged over 65 years, capable of movements and physical activities in daily life, were enrolled as subjects. The experimental method included a subjective satisfaction questionnaire evaluation of the elderly women using the target product, and the observation evaluation was achieved using video recording data, etc. Usability evaluation revealed that the elevating sector requires improvement of intuition through separation of the elevating control panel and the driving control panel. Improvements in the driving sector include corrections of the front wheel mechanism or driving control algorithm, UI, and sudden stop system. Transferring section assessment revealed a necessity to secure structures and add structures that support power. We believe that based on the inconveniences and improvements presented in the usability evaluation, appending the existing prototype with complementary products will improve the quality of life of elderly women with limited mobility.