• Journal of The Korea Institute of Healthcare Architecture
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• v.25 no.3
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• pp.25-36
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• 2019

Purpose: To establish guidelines for local public hospitals, the survey was conducted primarily on the current status of local public hospitals, focusing on the zone configuration and the spatial area of the operating department. Methods: 3 Methods have been used in this paper. 1) Analyzing drawings to derive the net floor area of each room. 2) A literature survey about composition of the zone by infection control. 3) Observation survey for user circulation analysis. Results: The operation department consists of the major, secondary, support and connected zones according to the user's actions. The spatial area composition ratio for each zone is major zone: 41.79%, secondary zone: 10.87%, support zone: 23.10%, and connected zone: 24.24%. Implications: This study is a basic research for guideline for the operation department in local public hospitals. In this study, zones configuration of the operation departments are classified in terms of user actions and room functions. In the future, it is required to establish criteria considering infection control and copper connection aspects.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.6
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• pp.734-740
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• 2023

Hydrogen emphasis on safety management due to its high potential for accidents from wide explosive limits and low ignition energy. To prevent accidents, appropriate explosion-proof electrical equipment with installed to safe management of ignition sources. However, designing all facilities with explosion-proof structures can significantly increase costs and impose limitations. In this study, we optimize the barrier to effectively control the initial momentum in case of hydrogen release and form the control room as a non-hazardous area. We employed response surface method (RSM), the barrier distance, width and height of the barrier were set as variables. The Box-Behnken design method the selection of 15 cases, and FLACS assessed the presence of hazardous area. Analysis of variance (ANOVA) analysis resulting in an optimized barrier area. Through this methodology, the workplace can optimize the barrier according to the actual workplace conditions and classify reasonable hazardous area, which is believed to secure safety in hydrogen facilities and minimize economic burden.

• Journal of Positioning, Navigation, and Timing
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• v.4 no.2
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• pp.67-72
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• 2015

Power grid techniques are distributed over general power systems ranging from power stations to power transmission, power distribution, and users. To monitor and control the elements and performance of a power system in real time in the extensive area of power generation, power transmission, wide-area monitoring (WAM) and control techniques are required (Sattinger et al. 2007). Also, to efficiently operate a power grid, integrated techniques of information and communication technology are required for the application of communication network and relevant equipment, computing, and system control software. WAM should make a precise power grid measurement of more than once per cycle by time synchronization using GPS. By collecting the measurement values of a power grid from substations located at faraway regions through remote communication, the current status of the entire power grid system can be examined. However, for GPS that is used in general national industries, unexpected dangerous situations have occurred due to its deterioration and jamming. Currently, the power grid is based on a synchronization system using GPS. Thus, interruption of the time synchronization system of the power system due to the failure or abnormal condition of GPS would have enormous effects on each field such as economy, security, and the lives of the public due to the destruction of the synchronization system of the national power grid. Developed countries have an emergency substitute system in preparation for this abnormal situation of GPS. Therefore, in Korea, a system that is used to prepare for the interruption of GPS reception should also be established on a long-term basis; but prior to this, it is required that an evaluation technique for the time synchronization performance of a GPS receiver using an atomic clock within the power grid. In this study, a monitoring system of time synchronization based on GPS at a power grid was implemented, and the results were presented.

• Journal of the korean academy of Pediatric Dentistry
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• v.8 no.1
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• pp.55-63
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• 1981

The purpose of this study is to observe the effect of formocresol and glutaraldehyde to tooth germs and periapical tissues after perforation of interradicular portion of pulpal floor and application of physiological saline solution in control groups, formocresol and glutaraldehyde in experimental groups. The following results were obtained 1. In control groups, normal healing processes were seen, and, on the sixteenth day, the epithelization of injured areas was completed. Inflammatory reactions were limited to the injured surface, and the underlying alveolar bone were normal and successive tooth germs were normal. 2. In both formocresol groups and glutaraldehyde groups, tissue reactions were identical. Inflammatory reactions were slightly compared with control groups, but the surface epithelizations were delayed compared with control group. 3. In both formocresol and glutaraldehyde groups, necrosis was seen in superficial tissue of bone marrow, and, at 24th day, center area of bone marrow on the successive tooth germs were losed and replaced with connective tissue, and superficial soft tissue of the injured area was connected with soft tissue on the successive tooth germ. In remaining alveolar bone, osteoclastic reaction was remarkable. 4. In both formocresol and glutaraldehyde groups, there is no injury to the successive tooth germs. 5. In both formocresol and glutaraldehyde groups, periodontal membrane was normal, but the partial resorption of cementum and dentin near the injured area were seen.

• Physical Therapy Korea
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• v.27 no.2
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• pp.126-132
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• 2020

Background: Augmented somatosensory feedback stimulates the mechanoreceptor to deliver information on bodily position, improving the postural control. The various types of such feedback include ankle-foot orthoses (AFOs) and vibration. The optimal feedback to mitigate postural sway remains unclear, as does the effect of augmented somatosensory feedback on muscle co-contraction. Objects: We compared postural sway and ankle muscle co-contraction without feedback (control) and with either of two forms of somatosensory feedback (AFOs and vibration). Methods: We recruited 15 healthy subjects and tested them under three feedback conditions (control, AFOs, vibration) with two sensory conditions (eyes open, or eyes closed and the head tilted back), in random order. Postural sway was measured using a force platform; the mean sway area of the 95% confidence ellipse (AREA) and the mean velocity of the center-of-pressure displacement (VEL) were assessed. Co-contraction of the tibialis anterior and gastrocnemius muscles was measured using electromyography and converted into a co-contraction index (CI). Results: We found significant main effects of the three feedback states on postural sway (AREA, VEL) and the CI. The two sensory conditions exerted significant main effects on postural sway (AREA and VEL). AFOs reduced postural sway to a level significantly lower than that of the control (p = 0.014, p < 0.001) or that afforded by vibration (p = 0.024, p < 0.001). In terms of CI amelioration, the AFOs condition was significantly better than the control (p = 0.004). Vibration did not significantly improve either postural sway or the CI compared to the control condition. There was no significant interaction effect between the three feedback conditions and the two sensory conditions. Conclusion: Lower-extremity devices such as AFOs enhance somatosensory perception, improving postural control and decreasing the CI during static standing.

• Journal of Biosystems Engineering
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• v.31 no.3 s.116
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• pp.146-152
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• 2006

Most upland in Korea have irregular field shapes. Boom sprayers working alone winding row will show considerable differences of spraying amount per unit area between left and right booms. If flow rates of both booms are equal. This phenomenon becomes significant as steering radius of sprayer decreases. This study was performed to seek a method which reduce the difference of the spray amount between left, right and center booms while spraying along curvy rows. A flow rate control method for keeping application rate of each boom section constant was proposed and experimentally proved using a boom sprayer attached to a cultivating tractor. The flow rate control device was composed of 3 ball valves and a rotary angle sensor. The rotary angle sensor showed a symmetric voltage output with respect to steering radius. The spray overlapping was happened in a boom nearby the steering center when steering radius of the sprayer was less than 5.2 m. Flow rates for left, right and center booms were regulated using ball valves based on the steering radius and spraying areas ration of right/left boom. The Maximum spraying area ratio ($S_{LR}$) of left to right boom section was 1:3.6 at the steering radius of 5.2 m. However, The Maximum achieved right and left spraying flow ratio was 1:2.7.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1178-1184
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• 2008

The effect of some peptides on hepatoprotection and cecal fermentation against D-galactosamine (GalN)-treated rats was studied. In acute hepatic injury tests, serum alanine aminotransferase (ALT), aspartate aminotranferase (AST), and lactic dehydrogenase (LDH) activities were remarkably increased after injection of GalN. However, potato and soybean peptides significantly decreased GalN-induced alterations of serum ALT and AST activities. Hepatic thiobarbituric acid-reactive substance (TBARS) concentration in GalN-treated groups fed potato and soybean peptides was significantly lower than that in GalN-treated control group. Hepatic glutathione level in the GalN-treated group fed potato peptide was significantly higher than that in GalN-treated control group. Furthermore, cecal Lactobacillus level in GalN-treated groups fed potato and soybean peptides was significantly higher than that in GalN-treated control group, and cecal short-chain fatty acid concentrations in GalN-treated group fed potato peptide were significantly higher than in GalN-treated control group. These results indicate that potato peptide may improve the cecal fermentation and prevent the GalN-induced liver damage in rats.

• Journal of Korea Society of Digital Industry and Information Management
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• v.16 no.1
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• pp.1-10
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• 2020

This paper is a IoT-based radon meter control system and a radon meter control method using it. The IoT-based radon meter control system is control system for controlling a radon meter by network-connecting radon meter and a user terminal. The radon measuring device may be provided with a radon sensor to measure a radon value of a preset management target area, it collect and store numerical data. The radon meter control system monitors the condition of the radon meter, it includes control center configured to deliver radon meter management information generated to a user terminal. Also radon measurements to determine the exact amount of radon gas. Therefore, the situation-specific actions based on radon numbers can be promptly implemented to ensure adequate protection for those who are vulnerable to radon and those who live in the area. Condition monitoring allows the radon meter to respond quickly to failure or failure of the radon meter. In addition, it is possible to secure a baseline of radon's influence and to obtain research data to cope with radon by establishing big data with radon measurements.

• The Journal of Advanced Prosthodontics
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• v.5 no.4
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• pp.374-381
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• 2013

PURPOSE. The purpose of this study was to evaluate the effect of alendronates on bone remodeling around titanium implant in the maxilla of rats. MATERIALS AND METHODS. The maxillary first molars were extracted and customized-titanium implants were placed immediately in thirty male Sprague-Dawley rats. The rats were divided into experimental (bisphosphonate) group and control group. At 4 weeks after implantation, the rats in the bisphosphonate group were subcutaneously injected with alendronate three times a week for 6 weeks where as the rats in control group were injected with saline. The rats were sacrificed at 1, 2, 3, 4, or 6 weeks after starting of injection and maxillary bones were collected subsequently. Alveolar bone remodeling around the implants were evaluated by radiographic and histologic analysis. Microarray analysis and immunohistomorphologic analysis were also performed on one rat, sacrificed at 6 weeks after starting of injection, from each group. Statistical analysis was performed using repeated measures analysis of variance and independent t test at a significance level of 5%. RESULTS. There was no statistically significant difference in the bone area (%) around implant between the bisphosphonate group and the control group. However, the amount of empty lacuna was significantly increased in the bisphosphonate group, especially in the rats sacrificed at 4 weeks after starting of injection compared to that of the corresponding control group. The bisphosphonate group showed the same level of TRAP positive cell count, osteocalcin and angiopoietin 1 as the control group. CONCLUSION. Alendronate may not decrease the amount of osteoclast. However, the significantly increased amount of empty lacuna in the bisphosphonate group may explain the suppression of bone remodeling in the bisphosphonate group.

• Journal of Sensor Science and Technology
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• v.21 no.2
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• pp.103-108
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• 2012

Radiofrequency(RF) signal is a key medium to the most of the present wireless communication devices including RF identification devices(RFID) and smart sensors. However, the most critical barrier to overcome in RFID application is in the failure rate in detection. The most notable improvement in the detection was from the introduction of EPC Class1 Gen2 protocol, but the fundamental problems in the physical properties of the RF signal drew less attention. In this work, we focused on the physical properties of the RF signal in order to understand the failure rate by noting the existence of the ground planes and noise sources in the real environment. By using the mathematical computation software, Maple, we simulated the distribution of the electromagnetic field from a dipole antenna when ground planes exist. Calculations showed that the dark area can be formed by interference. We also constructed a test system to measure the failure rate in the detection of a RFID transponder. The test system was composed of a fixed RFID reader and an EPC Class1 Gen2 transponder which was attached to a scanner to sweep in the x-y plane. Labview software was used to control the x-y scanner and to acquire data. Tests in the laboratory environment showed that the dark area can be as much as 43 %. One who wants to use RFID and smart sensors should carefully consider the extent of the dark area.