• Journal of the Korean Orthopaedic Association
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• v.54 no.4
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• pp.343-352
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• 2019

Purpose: The purpose of this study was to document the sonographic morphology of the subscapularis footprint, particularly the 1st facet, of the non-pathologic subscapularis tendon and footprint, and analyze the correlation between the size of the 1st facet and the demographic variables. Materials and Methods: Between March 2015 and December 2017, retrospectively data analysis was performed for the ultrasound (US) scans of 115 consecutive shoulder (mean age 53.4 years, range 23-74 years) with non-pathologic subscapularis tendon and footprint. The sonographic findings of the 1st facet of the subscapularis footprint was a very unique, flat, broad, and plane angle in the upward direction, which were distinguished from the other facets. On US, the transverse (medio-lateral) and longitudinal (superior-inferior) length of the 1st facet on axis of the humerus shaft were recorded. The demographic variables, including age, site, body height, weight, body mass index (BMI), and arm length, were reviewed. Results: On US, the mean transverse length of the 1st facet was 12.75 mm (range 10.54-14.50 mm, standard deviation [SD] 0.712) and the mean longitudinal length was 12.22 mm (range 9.20-13.30 mm, SD 0.888). The transverse and longitudinal length of the size of the 1st facet were significantly greater in males than in females (p<0.001, p=0.001). Of the demographic data (body height, weight, BMI, arm length) that showed a significant positive linear correlation, the correlation with body height (transverse r=0.749, p<0.001; longitudinal r=0.642, p<0.001) showed the strongest relationship, and the correlation with the BMI was weakly related. The relationships between the size of the 1st facet to site/age were not statistically significant or appeared to have no linear correlation. Conclusion: The structural and morphologic features of the 1st facet of the subscapularis footprint on the US were identified. This will provide anatomic knowledge of an US examination for subscapularis tendon pathology.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.2
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• pp.363-374
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• 2015

Instrumentation and control(I&C) system has been mainly designed and operated based on analog technologies in existing Nuclear Power Plants(NPPs). However, As the development of Information Technology(IT), digital technologies are gradually being adopted in newly built NPPs. I&C System based on digital technologies has many advantages but it is vulnerable to cyber threat. For this reason, cyber threat adversely affects on safety and reliability of I&C system as well as the entire NPPs. Therefore, the software equipped to NPPs should be developed with cyber security attributes from the initiation phase of software development life cycle. Moreover through cyber security assessment, the degree of confidence concerning cyber security should be measured and if managerial, technical and operational work measures are implemented as intended should be reviewed in order to protect the I&C systems and information. Currently the overall cyber security program, including cyber security assessment, is not established on I&C systems. In this paper, we propose cyber security assessment methods in the Software Development Life Cycle by drawing cyber security activities and assessment items based on regulatory guides and standard technologies concerned with NPPs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.252-260
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• 2021

For frailty management, the importance of resistance exercise has been emphasized, and various devices have been developed. Recently, digital weight control technology that converts electromagnetic resistance to a digital weight is attracting attention, but there are no reports confirming the effectiveness and safety of the device for seniors in Korea. This study conducted a biomechanic-based ergonomic analysis of an elderly-friendly exercise device utilized in digital load control technology to suggest a direction for development. Twenty seniors (age: 62.40 ± 2.09 years) were included. The load of the device was classified into three levels, and the muscle activity and heart rate were assessed during three experimental motions. A questionnaire based on the International Organization for Standardization 9241-11 was adopted to evaluate the stability, operationality, efficiency, and satisfaction with the software and device. The program could be divided into three exercise intensities that can be utilized in the field depending on whether the exercise load, muscle activity, and heart rate were consistent. The monitor size needed to be enlarged to make the menu Korean, reduce the device size, and minimize noise. Considering these findings, the development of an advanced age-friendly exercise device by improving the size, display, and noise is suggested.

• Journal of radiological science and technology
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• v.38 no.3
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• pp.253-259
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• 2015

The information of contrast media concentration on target organ is very important to get reduce the side effect and high contrast imaging. We investigated alternation of signal intensity as a function of the modality of Gd-based contrast media on spin echo and ultra short time echo (UTE) of T1 effective pulse sequence at 3T MRI unit. Gadoxetic acid, which is a MRI T1 contrast medium, was used to manufacture an agarose phantom diluted in various molarities, and sterile water and agarose 2% were used as the buffer solution for the dilution. The gold standard T1 calculation was based on coronal single section imaging of the phantom mid-point with 2D Inversion recovery spine-echo pulse sequence MR imaging for testing of phantom accuracy. The 1-2mmol/L and 7mmol/L was shown the maximum signal intensity on spin echo and UTE respectively. We confirm the difference of contrast media concentration which was shown the maximum signal intensity depending on the T1 effective pulse sequence.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.740-745
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• 2020

To calculate the reasonable design temperature load of a concrete box girder bridge, one bridge test specimen was made. The temperature gauges installed on the bridge test specimen measured 48 sets of temperature per day at 30-minute intervals during the summer and winter periods of one year. The temperature measured at each station was treated statistically to calculate the trend line and standard error, and the temperature distribution and trend line at the representative station were presented. The maximum effective temperature and the lowest effective temperature were calculated from the air temperature suggested by Euro code. The maximum effective temperature was calculated to be 1.5 to 2℃ higher than the Euro code at 35℃ and above. In comparison, the lowest effective temperature was 0.5 to 1.1℃ lower at -13℃ to-19℃. Compared to the effective temperature of this study according to the highest and lowest 50-year frequency of the Yangsan region, the highest effective temperature was 4.7℃ higher, and the lowest effective temperature was 4.5℃ lower. Considering the increasing climate change and reflecting the results of this analysis, it is deemed necessary to make the current temperature design standards larger.

• Journal of radiological science and technology
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• v.36 no.4
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• pp.273-280
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• 2013

This study was proven for the T-spine breathing technique in lateral projection, using computer radiography (CR), charge coupled device (CCD), indirect digital radiography (IDR) and direct digital radiography (DDR). All images were evaluated and compared with CNR and SNR measured with the mean pixels and the standard deviation as setting ROI of spinous process, pedicle, vertebral body, intervertebral foramen and intervertebral disk using Image J. In experiment results of 4 type detectors, T-spine breathing technique was indicated as excellent in ROI of spinous process, pedicle, vertebral body, intervertebral foramen and intervertebral disk. As T-spine breathing technique indicated excellent images compared to the existing T-spine lateral radiography, this method would be useful for elderly patients who have difficulty in deep exhalation. This study was indicated the application possibility of T-spine breathing technique by presenting contrast to noise ratio (CNR) and signal to noise ratio (SNR) with quantitative value in 4 type detectors.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.269-274
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• 2004

The marine electronic system for safe navigation such as ECDIS has been contributing to increase the safety of navigation, decreasing the mariner's load of navigation. The ECDIS should be developed and approved by international standard of IMO for performance standard and IEC for type-approval method and required results. However, these standards have some ambiguities for us not to directly adopt them for real approval system, so we should analyze them for more clear meaning and prepare our own detail standard for type-approval system. The first thing to do for the goal of this research was to analyze the standard in detail and make ambiguity be cleared in our own standards, considering each test item in view of test methodology. For the result of analysis we could develop more evident and detail type-approval standard for each test item with test technology needed. Especially, we developed the colour differentiation test process of ECDIS monitor, which include the colour differentiation formula derived from CIE colour scheme. Several test items require sensor informations of navigation equipment compatible with IEC 61162. We also developed the signal simulator for general messages of IEC 61162 that must be provided. Additionally, the type-approval processes and standards for Back-up arrangement and RCDS mode were developed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.6788-6798
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• 2015

In recent high speed rail way, the operating speed of train is enhanced and the introduction of EMU train vehicles is increased. In addition, as expected the demand of the concrete slab track and the trend of design cross-section reduction, the clear behavior of evaluation of internal slab layer is demanded about the variation of design load and speed. The purpose of this study is to evaluate and identify the mechanical behavior pattern of concrete slab track and track-road bed with the variation of axle load and train speed. To this end, the behavior of TCL and HSB was evaluated in according to the variation of axle load and speed. And the analysis results and the data measured TCL strain sensor, which was embedded in TCL slab under installation on Honam high speed railway, was analyzed. The analysis result shows that the strain are increasing in according to the speed-up of train, and line regression was obtained from measured data. Analysis data of the state of bonding condition of slab layer and measured data was analyzed. It is conducted that the TCL layer stress of HEMU 430X, which of axle load, is lighter was similar to the stress of KTX-Honam, the standard deviation of measured stress is dramatically increased.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.8
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• pp.1588-1596
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• 2015

In the Internet of Things (IoT), resource-constrained devices such as sensors are capable of communicating and exchanging data over the Internet. The IETF standard group has specified an application protocol CoAP, which uses UDP as a transport protocol, allows such a lightweight device to transmit data. Also, the IETF recommended the DTLS binding for securing CoAP. However, additional features should be added to the DTLS protocol to resolve several problems such as packet loss, reordering, fragmentation and replay attack. Consequently, performance of DTLS is worse than TLS. It is highly required for lightweight devices powered by small battery to design and implement a security protocol in an energy efficient manner. This paper thus discusses about DTLS performance in the perspective of energy consumption. To analyze the performance, we implemented IEEE 802.15.4 based test network consisting of constrained sensor devices in the Cooja simulator. We measured energy consumptions required for each of DTLS client and server in the test network. This paper compares the energy consumption and amount of transmitted data of each flight of DTLS handshake, and the processing and receiving time. We present the analyzed results with regard to code size, cipher primitive and fragmentation as well.

• Journal of radiological science and technology
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• v.40 no.3
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• pp.355-361
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• 2017

Pediatrics are more sensibility to radiation than adults and because they are organs that are not completely grown, they have a life expectancy that can be adversely affected by exposure. Therefore, the management of exposure dose is more important than the case of adult. The purpose of this study was to determine the suitability of the 10 year old phantom for the 5 year old pediatric's recommendation and the incident surface dose, and to measure the organ absorbed dose. This study is compared the organ absorbed dose and the entrance surface dose in the clinical conditions at 5 and 10 years old pediatric. Clinical 5 year old condition was slightly higher than recommendation condition and 10 year old condition was very high. In addition, recommendation condition ESD was found to be 43% higher than the ESD of the 5 year old group and the ESD of the 10 year old group was 126% higher than that of the 5 year old group. The recommended ESD at 5 years old and the ESD according to clinical imaging conditions were 31.6%. There was no significant difference between the 5 year old recommended exposure conditions and the organ absorbed dose due to clinical exposure conditions, but there was a large difference between the Chest and Pelvic. However, it was found that there was a remarkable difference when comparing the organ absorbed dose by 10 year clinical exposure conditions. Therefore, more detailed standard exposure dose for the recommended dose of pediatric should be studied.