• Nuclear Engineering and Technology
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• v.24 no.2
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• pp.183-192
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• 1992

An advanced load-follow operation mode, Mode K, is presented for the Korean Standardized Nuclear Power Plants. The Mode K utilizes a heavy worth bank dedicated to axial shape control independent of the existing regulating banks. In Mode K, the heavy bank provides a wide range of axial shape control and a monotonic relationship between its motion and the axial shape change, which makes it easy to automate axial shape control. The achievement of full automatic reactor power control both for the reactivity and power shape would reduce the burden due to load-follow operation on the operator. Also, it can accommodate the frequen-cy control, which requires the plant to respond to the unexpected demand. The Mode K design concepts were tested using simulation responses of Yonggwang Units 3&4, the reference plants for the Korean Standardized Nuclear Power Plants. The results illustrate that the Mode K is an adequate operation mode to provide practical load-follow capabilities for the Korean Standardized Nuclear Power Plants.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.4
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• pp.387-394
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• 2016

Today, hot rolled mill plant are currently operating 24 hours a day. The main processes of hot-rolled steel mill are Reheating Furnace, Roughing Mill, Fishing Mill and the Down Coiler. In the process checking over the thickness and width of rolled material, temperature control is an important factor. It is quite often the cause of the work breakdown and find a bad elements for product. After the shipping out the product, when a claim occurs requires an investigation. In each process of the conventional thickness gauge, width, and thermometer. Operation by an independent data acquisition and this monitoring is problematic and straining of the operator. The monitoring process the data of each function and incorporate monitoring results can also check future work. The installation of this system will improve our efficiency and productivity. In the rolling process by developing more efficient operating quality monitoring system, this will be made possible.

• Journal of the Korean Society of Safety
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• v.29 no.6
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• pp.166-171
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• 2014

Nuclear power plants are equipped with the reactor trip system (RTS) and the engineered safety features actuation system (ESFAS) to improve safety on the normal operation. In the event of the design basis accident (DBA), a various of post accident monitor(PAM)systems support to provide important details (e.g. Containment pressure, temperature and pressure of reactor cooling system and core exit temperature) to determine action of main control room (MCR). Operator should be immediately activated for the accident mitigation with the information. Especially, core exit temperature is a critical parameter because the operating mode converts from normal mode to emergency mode when the temperature of core exit reaches $649^{\circ}C$. In this study, uncertainty which was caused by exterior environment, characteristic of thermocouple/connector and accuracy of calibrator/indicator was evaluated in accordance with ANSI-ISA 67.04. The square root of the sum of square (SRSS) methodology for combining uncertainty terms that are random and independent was used in the synthesis. Every uncertainty that may exist in the hardware which is used to measure the core exit temperature was conservatively applied and the associative relation between the elements of uncertainty was considered simultaneously. As a result of uncertainty evaluation, the channel statistical allowance (CSA) of single channel of core exit temperature was +1.042%Span. The range of uncertainty, -0.35%Span ($-4.05^{\circ}C$) ~ +2.08%Span($24.25^{\circ}C$), was obtained as the operating criteria of core exit temperature.

• Archives of Plastic Surgery
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• v.38 no.6
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• pp.719-724
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• 2011

Purpose: Previous studies of the facial artery have shown significant anatomical variability in this region. The vascular anatomy of the region is considered unreliable in predicting the ideal pedicle. Preoperative imaging has been suggested as a means of improving preoperative awareness, with Doppler ultrasound as useful tools. Multi-detector row angiographic computed tomography (angio CT) is a significant improvement, providing noninvasive operator-independent details of the vascular anatomy. This tool was used to perform an $in$ $vivo$ anatomical study of the facial artery, demonstrating the usefulness of facial angio CT in planning the facial reconstruction. Methods: Eleven consecutive patients underwent facial angio CT of the facial vasculature with the anatomical details of the facial artery assessed. Results: Facial angio CT could demonstrate the size and course of the facial vasculature, particularly the facial artery. Conclusion: The vascular anatomy of the facial artery is highly variable, and thus there is a role for preoperative imaging. Facial angio CT can demonstrate cases where there is an aberrant or non-preferred anatomy, or select the method of a facial reconstruction.

• Journal of The Korean Dental Society of Anesthesiology
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• v.4 no.2 s.7
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• pp.90-95
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• 2004

Background: Sevoflurane, a rotatively new inhalational anesthetic. has non-pungent odor and is less reluctant to pediatric patients. The purpose of this study is to examine the feasibility of sevoflurane in inhalational sedation instead of the nitrous oxide for short and simple dental treatments in pediatric patients. Patients and Methods: Fifteen healthy children, whose dental treatment was abandoned due to their little or no cooperation, were selected with their caregivers' written permission. Deep sedation was induced and maintained with oxygen and 1-5% sevoflufane via specially designed nasal mask. Blood pressure, heart rate, oxygen saturation, and electrocardiogram were monitored at 3-nin interval. A dental anesthesiologist, who was independent of dental treatments, was wholly responsible for the sedation procedure. Post-sedation complications and operator's and caregiver's acceptability of this type of inhalational sedation were also investigated. Results: The systolic and diastolic blood pressure, heart rate, and oxygen saturation was significantly depressed during the deep sedation using sevoflurane (P < 0.05). No severe post-sedation complications were found, however, bradycardia was reported in 3 patients. Almost all the operators and caregivers answered that they would adapt this sedation procedure again if possible. Conclusion: In this study, inhalational deep sedation using sevoflurane for dental treatments was found to be very useful. Furthermore, the application of sevoflurane to conscious sedation for pediatric and adult dental patients should be added.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.12
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• pp.1932-1938
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• 2012

The impedance cardiogram has been proposed as a non-invasive, continuous, operator independent, and cost-effective method for cardiac output monitoring. However, it can not be completely considered as non-restrictive method because of attached spot and band type electrodes. Therefore, we developed a improved convenient hand-held typed measurement system for cardiac output by electrical impedance technique. 80 subjects from Yonsei University and the surrounding areas, participated. All subjects measured stroke volume and cardiac output through Physioflow and developed system. To verify the developed system, statistical methods such as correlation, Wilcoxon signed ranks test, and the Bland-Altman analysis were used. The proposed system showed significant correlation in both male and female stroke volume(r=0.715, r=0.704) and cardiac output(r=0.826; r=0.804). From these results, it can be concluded that stroke volume and cardiac output could be improved convenient measurement using the both hands without the help of a specialist.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.2
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• pp.227-234
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• 2019

A user-friendly modeling interface is developed for a process-based total system performance assessment framework (APro) specialized for a generic geological disposal system for high-level radioactive waste. The APro modeling interface is constructed using MATLAB, and the operator splitting scheme is used to combine COMSOL for simulation of multiphysics and PHREEQC for the calculation of geochemical reactions. As APro limits the modeling domain to the generic disposal system, the degree of freedom of the model is low. In contrast, the user-friendliness of the model is improved. Thermal, hydraulic, mechanical and chemical processes considered in the disposal system are modularized, and users can select one of multiple modules: "Default process" and multi "Alternative process". APro mainly consists of an input data part and calculation execution part. The input data are prepared in a single EXCEL file with a given format, and the calculation part is coded using MATLAB. The final results of the calculation are created as an independent COMSOL file for further analysis.

• The Journal of Korean Association of Computer Education
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• v.21 no.6
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• pp.39-47
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• 2018

This paper dealt with investigating the number of minimal spanning ladders originated from ladder game and their properties as well as the related computational thinking aspects. The author modified the filtering techniques to enhance Mathematica project where a new type of graph was generated based on the algorithm using a generator of firstly found minimal spanning graph by repeatedly applying independent ladder operator to a subsequence of ladder sequence. The newly produced YC graphs had recursive and hierarchical graph structures and showed the properties of edge-symmetric. As the computational complexity increased the author divided the whole search space into the each floor of the newly generated minimal spanning graphs for the (5, 10) YC graph and the higher (6, 15) YC graph. It turned out that the computational thinking capabilities such as data visualization, abstraction, and parallel computing with Mathematica contributed to enumerating the new YC graphs in order to investigate their structures and properties.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.3
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• pp.427-432
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• 2023

In this study, MEC (: Multi-access Edge Computing) proposes a cloud service network configuration for various tests of autonomous vehicles to which V2X (: Vehicle to Everything) is applied in Wave, LTE, and 5G networks and MEC App (: Application) applied V2X service function test verification of two domains (operator (KT, SKT, LG U+), network type (Wave, LTE (including 3G), 5G)) in a specific region. In 4G networks of domestic operators (SKT, KT, LG U+ and Wave), MEC summarized the improvement effects through V2X function blocks and traffic offloading for the purpose of bringing independent network functions. And with a high level of QoS value in the V2X VNF of the 5G network, the traffic steering function scenario was demonstrated on the destination-specific traffic path.

• The Journal of Advanced Prosthodontics
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• v.15 no.3
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• pp.126-135
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• 2023

PURPOSE. The aim of this study was to evaluate the reliability of implant stability measuring devices depending on the location of the implant and the position of the patient. MATERIALS AND METHODS. Six implants were installed in different dentate sextants of six artificial bone models. Implant stability was measured in three conditions of the bone model (without mounting on a phantom head, mounted on a phantom head in supine position, and mounted on a phantom head in upright position). A resonance frequency analysis device (Osstell) and two damping capacity analysis devices (Periotest and Anycheck) were used to measure implant stability. The values measured outside the phantom head were treated as controls, and the values inside the phantom head were compared using an independent t-test. RESULTS. Osstell showed different results in two of the six divisions in both the supine and upright positions compared to outside of the mouth (P < .05). Periotest showed different results in all six parts in the supine position and in five parts in the upright position compared to outside of the mouth (P < .05). While Anycheck showed different results in five areas in the supine position compared to outside of the mouth, it showed different results in only one area in the upright position (P < .05). CONCLUSION. In the difficult implant position for the operator to access, the implant stability measuring devices show less reliability. The accessibility of implant is greatly affected in the order of Osstell, Anycheck, and Periotest.