• Journal of Positioning, Navigation, and Timing
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• v.12 no.3
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• pp.281-288
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• 2023

The International Maritime Organization (IMO) states that the recommended horizontal accuracy for coastal and offshore areas is 10 m, the Alert Limit (AL) is 25 m, the time to alert is 10 seconds, and the integrity risk (IR) is 10^-5 per three hours. For operations requiring high accuracy, such as tugs and pushers, icebreakers, and automated docking, the IMO dictates that a high level of positioning accuracy of less than one meter and a protection level of 0.25 meters (for automated docking) to 2.5 meters should be achieved. In this paper, we analyze a method of calculating the user-side protection level of the centimeter-level precision Global Navigation Satellite System (GNSS) that is being studied to provide augmentation information for the precision Positioning, Navigation and Timing (PNT) service. In addition, we analyze standardized integrity forms based on RTCM SC-134 to propose an integrity information form and generate a centimeter-level precise PNT service plan.

• The Journal of Engineering Geology
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• v.24 no.2
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• pp.227-235
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• 2014

The deformation modulus is one of the essential factors in determining ground behavior and safety during tunnel excavation. In this study, we conducted a back-analysis using crown settlements measured during tunnel excavation, using a horizontal inclinometer on a fault zone of pegmatite, and calculated the deformation modulus of the fault zone. This deformation modulus calculation was then compared with deformation moduli found through established relationships that use the correlation between RMR and the deformation modulus, as well as the results of pressure-meter tests. The deformation moduli calculated by back-analysis differs significantly from the deformation moduli determined through established relationships, as well as the results from pressure-meter tests conducted across the study area. Furthermore, the maximum crown settlements derived from numerical analysis conducted by applying deformation moduli determined by these established relationships and the pressure-meter tests produced noticeable differences. This result indicates that in the case of a weak rock mass, such as a fault zone, it is inappropriate to estimate the deformation modulus using preexisting relationships, and caution must be taken when considering the geological and geotechnical characteristics of weak rock.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.1
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• pp.51-56
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• 2017

In this paper, we have developed a differential pressure flow sensor designed as a single capacitive type. And the sensor was fabricated using a MEMS process. Differential pressure flow sensors are the most commonly used sensors for industrial applications. The sensing diaphragm and bonding joint of the MEMS pressure sensor are easily broken at high pressure. In this paper, we proposed a structure in which the diaphragm of the sensor was not broken at a pressure exceeding the proof pressure, and the differential pressure sensor was designed and manufactured accordingly. The operating characteristics of the sensor were evaluated at a pressure three times higher than the sensor operating pressure (0-3 bar). The developed sensor was $3.0{\times}3.0mm$ and measured with a LCR meter (HP 4284a) at a pressure between 0 and 3 bar. It showed 3.67 pF at 0 bar and 5.13 pF at 3 bar. The sensor operating pressure (0-3 bar) developed a pressure sensor with hysteresis of 0.37%.

• Journal of the Korean Society of Physical Medicine
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• v.5 no.2
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• pp.193-201
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• 2010

Purpose : This study achieved to search the effect of the circuit exercise and conventional exercise on walking ability(walking speed, endurance, dynamic balance, speed, endurance and pedestrian crossing) in chronic stroke. Methods : Since is diagnosed by stroke, to 30 chronic stroke patients who more than 1 year past the 15 circuit exercise group, the 15 conventional exercise group random the circuit exercise group applied circuit exercise 3th 8 weeks each week after neurological treatment because assigning and the conventional exercise group executed round trip walk exercise in parallel bar 3th 8 weeks each week after neurological treatment. The data of 25 patients who complete experimental course were statistically analysed. Results : The results of this dissertation were as following : 1) There were significantly increased after experimental of 10 meter walk test, 6 minutes walk test and Timed "Up and Go" test in circuit exercise group (p<.001). 2) There were significantly increased after experimental of 2, 4 and 6 lane road crossing mobility in Walking circuit exercise group(p<.01). 3) There were significantly differences after experimental of 10 meter walk test, 6 minutes walk test and Timed "Up and Go" test change quantity between circuit exercise group and conventional exercise group(p<.05). 4) There were correlations were found between the TUG test and 2, 4 and 6 lane road (2 lane road; r=.463, p<.01., 4 lane road; r=515, p<.01., 6lane road; r=.710, p<.01), and there were correlations were found between the 10 meter walk test and 6 minutes walk test(r=.595, p<.01), TUG test(r=.662, p<.01) and 6 lane road(r=.527, p<.01). Conclusion : Even if improvement of walk function through training consists in room, transfer of actuality pedestrian crossing is no change outside the room. Because it is much variable of the weather, seasonal factor, temperature, pedestrian number, state of underneath etc. outside the room. Then, in room after direction promotion of walk function to be promotion of walk function in actuality life and need development of connectable training method consider.

• Korean Journal of Materials Research
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• v.25 no.2
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• pp.90-94
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• 2015

We prepared 8 samples of non-silver and silver-added master alloys containing silicon to confirm the existence of nickel-silicides. We then prepared products made of 14K and 18K white gold by using the prepared master alloys containing 0.25, 0.35, and 0.50 wt% silicon to check for nickel release. We then employed the EN 1811 testing standard to investigate the nickel release of the white gold products, and we also confirmed the color of the white gold products with an UV-VIS-NIR-color meter. We observed $NiSi_x$ residue in all master alloys containing more than 0.50 wt% Si with EDS-nitric acid etching. For the white gold products, we could not confirm the existence of $NiSi_x$ through XRD after aqua-regia etching. In the EN 1811 test, only the white gold products with 0.25 wt% silicon master alloys successfully passed the nickel release regulations. Moreover, we confirmed that our white gold products showed excellent Lab indices as compared to those of commercial white gold ones, and the silver-added master alloys offered a larger L index. Our results indicate that employing 0.25 wt% silicon master alloys might be suitable for white gold products without nickel-silicide defects and nickel release problems.

• Journal of the Korean Society of Physical Medicine
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• v.13 no.2
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• pp.137-145
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• 2018

PURPOSE: The purpose of this study was to investigate the effect of action observational physical training with rhythmic auditory stimulation on muscle activity and gait ability in patients with stroke. METHODS: Twenty-six chronic stroke patients participated in this study were assigned into three groups, experimental group 1 (10% faster tempo rhythmic auditory stimulation with action observation training) n=8, experimental group 2 (average tempo rhythmic auditory stimulation with action observation training) n=9, and control group (action observation training) n=9. In this experiment, the corresponding exercise were applied into the subjects of three group for 30 minute a day, 3 time a week during 4 weeks. All participants were measured to muscle activity of lower limb, 10 meter walking test, Figure of 8 walk test, Dynamic gait Index. The collected data were analyzed by using SPSS (version 18.0 for window) and verified that each data was a normal distribution based on Shapiro-Wilk test. Between-group and within-group comparison was analyzed by using One-way ANOVA test, Paired t-test respectively. In all statistical analyses, significance level, ${\alpha}$ was set by .05. RESULTS: The above results revealed that the all experimental group 1 and experimental group 2 and control group were all effective to improve the lower limb muscle activities, gait ability. However more positive effects shown action observational physical training with rhythmic auditory stimulation experimental group. CONCLUSION: This study suggest that action observation physical training with rhythmic auditory stimulation is effective intervention for improvement of muscle activity and walking ability in chronic stroke patients.

• Water Engineering Research
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• v.2 no.2
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• pp.123-138
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• 2001

An injection experiment was carried ut to investigate the pressure domain within which hydromechanical coupling influences considerably the hydrologic behavior of a granite rock mass. The resulting database is used for testing a numerical model dedicated to the analysis of such hydromechanical interactions. These measurements were performed in an open hole section, isolated from shallower zones by a packer set at a depth of 275 m and extending down to 840 m. They consisted in a series of flow meter injection tests, at increasing injection rates. Field results showed that conductive fractures from a dynamic and interdependent network, that individual fracture zones could not be adequately modeled as independent systems, that new fluid intakes zones appeared when pore pressure exceeded the minimum principal stress magnitude in that well, and that pore pressures much larger than this minimum stress could be further supported by the circulated fractures. These characteristics give rise to the question of the influence of the morphology of the natural fracture network in a rock mass under anisotropic stress conditions on the effects of hydromechanical couplings.

• Korean Journal of Adult Nursing
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• v.21 no.6
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• pp.678-690
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• 2009

Purpose: This study was performed to identify skin health status and the factors influencing skin hydration in the institutionalized elderly. Methods: The subjects were 139 elders living in 2 nursing homes in Seoul. Data for skin health status were collected by measurement of skin hydration, sebum, trans-epidermal water loss and pH using Corneometer, Sebumeter, Tewameter and Skin pH-meter on face, flank, arm and leg. Baseline data were collected by a structured questionnaire. The data were analyzed by SPSS/WIN 12.0 program. Results: Skin hydration and pH were relatively low especially on arms and legs but sebum and TEWL were not low, relatively. There were significant differences in skin health status according to gender, smoking, alcohol intake, and bath cleanser. There was significant positive correlation between skin-hydration and bath-time, TEWL and bath-frequency. Smoking, bath-cleanser, bath-time. pH and gender were identified as the significant influencing factors of skin hydration. Conclusion: Smoking, bath-time and pH need to be considered as important control factors for increasing skin health status in the institutionalized elderly.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.4
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• pp.34-39
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• 2013

For orthopedic artificial metal stainless steel, the magnetization of the magnetic field due to the presence of the titanium was to observe the change. Magnetic field meter (Tesla meters) a certain distance (ISO Centre) 1.5 Tesla magnetic field, the magnetization in the center with the passage of time were measured. Therefore, these artificial metal clip shape and magnetization of the sample size to produce a ferromagnetic material for comparison is the experimental dependence. For comparison of the experimental dependence of the magnetization, thereby producing a test piece size such as shaping prosthetic metal Clip is a ferromagnetic material. The experimental results, the metal orthopedic implants, there was no change in the magnetization indicated by ferromagnetic material in its natural state. However, in a magnetic field of 1.5T (Tesla), showed a sensitivity that is magnetized rapidly compared to the ferromagnetic material. In conclusion, high in the order of Clip, Stainless, of Titanium, the degree of dependence of the magnetization intensity of magnetization was the order Stainless, Titanium, of Clip in a magnetic field.

• Journal of Wetlands Research
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• v.3 no.2
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• pp.133-142
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• 2001

Growth of cities and an increase in population result in the development-oriented policy, urban streams to lose their natural characteristics and functions by channelization, parking lot construction, and so forth. The streams fall into urban drains, which is the current status of urban streams. Recently, the interest in the stream environment and the ecosystem has been increased, and the efforts have been made to improve the traditional maintenance program for small streams. These efforts lead to the application of the natural recovery systems. This study applied the 240-meter model reach along the Oncheon stream, which locates in Dongrae-gu, Busan city. to analyze the natural recovery system. The efficiency of each system has been analyzed and the future improvements for the systems are presented. The results show that the stream maintenance program should consider the ecological environment. thereby minimizing the environmental effects. When the changes are inevitable, the maintenance program should adopt the methods. which closely simulate the original environmental elements. or are more favorable to the ecosystem.