• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.11
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• pp.1262-1270
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• 2007

In this paper, we propose a new distortion cancellation mechanism for a balanced power amplifier structure using the carrier cancellation loop of a feedforward and post-distortion technique. The proposed cross post-distortion balanced linear amplifier can reduce nonlinear components as much as the conventional feedforward amplifier through the output dynamic range and broad bandwidth. Also the proposed system provides higher efficiency than the feedforward. The capacities of power amplifier and error power amplifier in the proposed system are analyzed and compared with those of feedforward amplifier. Also the operation mechanisms of the three kind loops are explained. The proposed cross post-distortion balanced linear power amplifier is implemented at the IMT-2000($f_0=2.14\;GHz$) band. With the commercial high power amplifiers of total power of 240 W peak envelope power fer base-station application, the adjacent channel leakage ratio measurement with wideband code division multiple access 4FA signal shows 18.6 dB improvement at an average output power of 40 dBm. The efficiency of fabricated amplifier Improves about 2 % than the conventional feedforward amplifier.

• The Journal of the Korea Contents Association
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• v.16 no.1
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• pp.158-166
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• 2016

This study is a nonequivalent control group pre- and post-test design research whose purpose was to determine what effects the pre-operation provision of information has on the anxiety and uncertainty of mothers with a pre-school child of tonsillectomy and nursing satisfaction after the operation. Data were collected from mothers whose child underwent tonsillectomy at S general hospital. For the collection, those mothers were divided into the experimental and control groups, respectively consisting of 19 and 20 members. The experimental group was provided general education about the operation. In addition, they individually received information about the procedure that the researcher and an assistant provided on one-to-one basis for about 20 minutes, in which brochures containing the information were used. While, the control group was provided only general education as mentioned above. For data analysis, this study conducted ${\chi}^2$-test, Fisher's exact test and Mann-Whitney U-test. The pre-operation provision of information was found having brought significant differences between the control and experimental groups in their anxiety(U=104.5, p=.015) and uncertainty(U=83.5, p=.002) as well as their satisfaction after the operation(U=109.5, p=.022). The findings of this study strongly suggest that information provision before the operation is positively effective in reducing the anxiety and uncertainty of mothers with a tonsillectomy child and increasing their nursing satisfaction after the operation. These effects need to be more verified through repetitive and subsequent researches and by using many other methods of information provision.

• Journal of Astronomy and Space Sciences
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• v.38 no.3
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• pp.185-192
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• 2021

This technical paper deals the practical transformation algorithms between several lunar reference frames which will be used for Korea pathfinder lunar orbiter (KPLO) flight operation. Despite of various lunar reference frame definitions already exist, use of a common transformation algorithm while establishing lunar reference frame is very important for all members related to KPLO mission. This is because use of slight different parameters during frame transformation may result significant misleading while reprocessing data based on KPLO flight dynamics. Therefore, details of practical transformation algorithms for the KPLO mission specific lunar reference frames is presented with step by step implementation procedures. Examples of transformation results are also presented to support KPLO flight dynamics data user community which is expected to give practical guidelines while post processing the data as their needs. With this technical paper, common understandings of reference frames that will be used throughout not only the KPLO flight operation but also science data reprocessing can be established. It is expected to eliminate, or at least minimize, unnecessary confusion among all of the KPLO mission members including: Korea Aerospace Research Institute (KARI), National Aeronautics and Space Administration (NASA) as well as other organizations participating in KPLO payload development and operation, or further lunar science community world-wide who are interested in KPLO science data post processing.

• Journal of the Korean Burn Society
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• v.22 no.2
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• pp.34-37
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• 2019

Fires in operating rooms rarely occur. However, this type of disaster can complicate almost any surgical procedure. Fuel, heat and oxygen are related with fire outbreak. When ignition sources such as alcohol-based surgical preparation solutions are present, the risk of an operating room fire increases, and burns are more severe in such conditions. Many manufacturers recommend waiting at least three minutes after application to allow complete drying for reduce fire risk. There are a few studies regarding flame burns in the operation room, although most of these studies are related to preoperative skin preparation. However, alcohol containing solutions can be used occasionally for cleansing of the operation field after the surgery, therefore, the surgical team should pay attention to surgical fires, even if they have completed the operation successfully. We present our case of a post-operative flame burn and introduce some precautions that will reduce the risk of alcohol burns.

• Journal of the Society of Disaster Information
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• v.20 no.1
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• pp.232-243
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• 2024

Purpose: Recently, large-scale forest fires caused by climate change, natural disasters, and human factors have been increasing every year in the East Coast and Taebaek Mountains region. Although forest fire extinguishing using helicopters is currently increasing, the need to introduce air force transport aircraft has continued to be raised due to the importance of early fire extinguishment to respond to large forest fires and the difficulty of extinguishing forest fires between sheep. This study seeks to present a plan for developing a post-fire management system for several aspects - achieving operational objectives, overcoming the operating environment, selecting a staging area, and efficient operation measures - to efficiently perform forest fire extinguishing missions using Air Force transport aircraft. Method: Based on literature research on forest fire extinguishing, forest fire extinguishing experiments using fixed-wing aircraft, and the operation status and operation method of forest fire extinguishing helicopters, the pros and cons of helicopter operation and the effects of large forest fire extinguishing using a large transport aircraft (C-130) Analyze the effectiveness of operation through analysis. Results: When extinguishing a large forest fire, an effective CM (Consequence Management) application plan was derived, including effective operation, control, command system, dispatch request, and forest fire extinguishment when integrating helicopter and fixed-wing aircraft (C-130). Conclusion: The application of the concept of CM (Consequence Management) is partially applied to some areas of chemical, biological, and radiological (CBRNE) protection in Korea, but efficient operation, control, and command systems are established when integrated operation of helicopters and large aircraft (C-130) in forest fire extinguishment. the concept of CM (Consequence Management), which is operated in advanced countries, was applied for safety management, dispatch requests, and forest fire extinguishing, thereby contributing to the establishment of a more advanced disaster and post-disaster management system.

• ETRI Journal
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• v.35 no.3
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• pp.448-458
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• 2013

This paper presents a generalized post-processing technique for enhancing the pseudorandomness of digital chaotic oscillators through a nonlinear XOR-based operation with rotation and feedback. The technique allows full utilization of the chaotic output as pseudorandom number generators and improves throughput without a significant area penalty. Digital design of a third-order chaotic system with maximum function nonlinearity is presented with verified chaotic dynamics. The proposed post-processing technique eliminates statistical degradation in all output bits, thus maximizing throughput compared to other processing techniques. Furthermore, the technique is applied to several fully digital chaotic oscillators with performance surpassing previously reported systems in the literature. The enhancement in the randomness is further examined in a simple image encryption application resulting in a better security performance. The system is verified through experiment on a Xilinx Virtex 4 FPGA with throughput up to 15.44 Gbit/s and logic utilization less than 0.84% for 32-bit implementations.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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• pp.25-30
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• 2007

Most part of the energy consumption of MIC(Ministry of Information and Communication) is mainly due to operation/maintenance of the post office buildings. In this paper, the pattern of energy consumption & operating status in post office buildings in Korea is analyzed. The authors suggest integrated and grouped management of the dispersed post office buildings using internet, through which we can expect increased efficiency.

• Journal of Chest Surgery
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• v.10 no.2
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• pp.190-194
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• 1977

An analysis of 503 pulmonary resection is presented, with the following points of interest; 1] By using a stapling device, the operation time is shortened, more lung tissue can be saved, and post-operative complications are fewer. 2] By comparison with a previous series, postoperative drainage from the chest is decreased when the stapling device is used. In the present series 82% of patients has less than 500 cc of drainage post-operatively. Average required whole blood replacement was less than 800 cc in this series of patients. 3] Only 13 patients, or 2.6% developed a bronchopleural fistula, and only 8 patients, or 1.5% developed post-operative empyema when the stapling device was used. 4] Because of the decreased air leaks when the stapling device is used, the anterior and posterior tubes can be removed sooner. 5] With careful preservation of lung tissue and paralysis of the phrenic nerve, post operative `dead space" is not a problem after the pulmonary lobectomy. Thus thoracoplasty is not necessary to eliminate "dead space".

• Journal of the Korean Graphic Arts Communication Society
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• v.27 no.1
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• pp.107-118
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• 2009

The printing industry is getting more digitalized and integration. It has enabled the interactive information and networking from Pre-Press, Press, to the Post-Press. These are efficient management and the improved process and productivity are getting more important. Such trends improved in the functionality and automation. This paper tries to find out how technology for CIP3/4-based process may be applied and resolved. Such subject includes the domestic and international cases regarding each manufacturer's CIP3/4 technology types. Another purpose is to emphasize on the needs to establish the environment. Under this environment, it is possible to integrate network in exchangeable form through JDF standard format after CIP3/4. Based on the data from this study, it is expected to collect further substantial data which is related to the domestic printing company's CIP4 operation. It will be also possible to perform subsequent studies on the proper variables of the market segment. CIP4 stands for "International Cooperation for Integration of Prepress, Press and Post-press, it is an association of around forty international companies, mostly manufacturers of prepress, press and post-press, as well as suppliers and users. In this paper, we studied on the acting application of CIP4 workflow.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.39 no.4
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• pp.188-192
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• 2013

Post-traumatic anterior open bite can occur as a result of broken balance among the masticatory muscles. The superior hyoid muscle group retracts the mandible downward and contributes to the anterior open bite. Denervation of the digastric muscle by injection of botulinum toxin type A (BTX-A) can reduce the power of the digastric muscle and help to resolve the post-traumatic anterior open bite. A patient with a bilateral angle fracture had an anterior open bite even after undergoing three operations under general anesthesia and rubber traction. Although the open bite showed some improvement by the repeated operation, the occlusion was still unstable six weeks after the initial treatment. To eliminate the residual anterior open bite, BTX-A was injected into the anterior belly of the digastric muscle. Following injection of BTX-A, the anterior open bite showed immediate improvement. Complication and relapse were not observed during follow-up. Long-standing post-traumatic open bite could be successfully corrected by injection of BTX-A into the anterior belly of the digastric muscle without complication.