• The Journal of the Korea Contents Association
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• v.18 no.7
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• pp.577-589
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• 2018

The future of ROK-US alliance has not been discussed in detail by both governments since early 2000s. However, it is becoming more apparent that ROK-US alliance is facing various daunting challenges. The new administrations both in ROK and US might have different perspectives about the future of alliance. In the process of resolving outstanding North Korean nuclear issue, the alliance can face challenges to change its fundamental features such as halting joint military exercise. ROK-US governments also agreed to transfer wartime operational control as soon as possible. All those factors indicates the growing necessity to articulate the future of ROK-US alliance. ROK and US needs to facilitate to dialogue for future alliance with the possible scenarios of changing security environment such as maintaining status quo, reconciliation of North and South Korea, and entering the reunification stage. In each phase, ROK-US has to develop the goal for the alliance, military institution to implement the alliance, role of USFK, and etc. It is imperative to develop the road map for future ROK-US alliance at this stage to avoid unnecessary folly.

• Korean Journal of Radiology
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• v.21 no.4
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• pp.442-449
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• 2020

Objective: To compare the diagnostic performance of contrast-enhanced spectral mammography (CESM) versus ultrasonography (US) in symptomatic patients with dense breasts, while using histology as the gold standard. Materials and Methods: After obtaining approval from the local ethics board, this prospective study collected data from patients with symptomatic breasts who underwent CESM and US examinations from May 1, 2017 to September 30, 2017. We then selected those with dense breasts and pathological results as our sample population. Both CESM and US results were classified by a radiologist through the Breast Imaging Reporting and Data System, and the results were compared with their corresponding histological results. The chi-square test was conducted to compare the diagnostic performance of CESM and US, and the receiver operating characteristic curves for the two imaging modalities were obtained. Results: A total of 131 lesions from 115 patients with dense breasts were included in this study. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were 93.8%, 88.1%, 88.2%, 93.7%, and 90.8% for CESM, and 90.6%, 82.1%, 82.9%, 90.2%, and 86.3% for US, respectively. The p values for sensitivity, specificity, PPV, NPV, and accuracy were 0.687, 0.388, 0.370, 0.702, and 0.238, respectively. The area under the curve of CESM (0.917) was comparable with that of US (0.884); however, the differences between CESM and US were not statistically significant (p = 0.225). Eight false-positive cases and 4 false-negative cases for breast cancer were found in CESM, while 12 false-positive cases and 6 false-negative cases were found in US. Conclusion: The diagnostic performances of CESM and US are comparable in symptomatic women with dense breasts; however, the routine use of additional US imaging is questionable for lesions that can be detected by CESM.

• The Korean Journal of Air & Space Law and Policy
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• v.29 no.2
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• pp.183-204
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• 2014

US 911 incidents have changed all aviation security system in the world. Especially the US changed all existing system into new one. One of the most fundamental changes is aviation security acts, regulation and several programmes. Based on the new aviation security act enacted in 2001, several code of federal regulations have been amended to strengthen US aviation security system. These regulation also enable new aviation security programmes including several airline and airport security related programmes, K-9 programme, BDO programme and air marshall programmed. All the programmes enables US aviation security improvements. Also the creating of TSA based on the aviation and transportation security act has provided the enhancement of aviation security in US. The purpose of this thesis is studying the change of aviation security system in the US especiatly in terms of aviation security legislation perfective and comparing the system with Korean aviation security legal system and provides possible solution to enhance Korean aviation security legislation and structure.

• Korean Journal of Radiology
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• v.22 no.5
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• pp.677-687
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• 2021

Microvascular ultrasound (US) techniques are advanced Doppler techniques that provide high sensitivity and spatial resolution for detailed visualization of low-flow vessels. Microvascular US imaging can be applied to breast lesion evaluation with or without US contrast agents. Microvascular US imaging without a contrast agent uses a sophisticated wall filtering system to selectively obtain low-flow Doppler signals from overlapped artifacts. Microvascular US imaging with second-generation contrast agents amplifies flow signals and makes them last longer, which facilitates hemodynamic evaluation of breast lesions. In this review article, we will introduce various microvascular US techniques, explain their clinical applications in breast cancer diagnosis and radiologic-histopathologic correlation, and provide a summary of a recent radiogenomic study using microvascular US.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.10
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• pp.575-580
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• 2017

Chlorinated hydrocarbons (TCE and PCE), petroleum hydrocarbons (BTEX, PAHs, and TPH), and explosive compounds (TNT, RDX, and HMX) have been detected in underground water countrywide. The overall objective of this study is to evaluate sono-catalytic degradation coupled with the use of PUV in order to understand the fate and transport of a representative selection of non-biodegradable contaminants (i.e., TCE, PCE, BTEX, PAHs, TPH, TNT, RDX, and HMX) in groundwater. Both ultraviolet (UV) and ultrasound (US) systems are used in degrading of organic contaminants and they can thus be applicable simultaneously as an UV/US hybrid system in attempts further to increase the degradation efficiency. Results indicate that synergistic effect of UV/US hybrid system is closely correlated to the enhancement of sono-chemical reactivity with the UV-US interaction of increasing the formation rate of OH by providing additional $H_2O_2$ production through the pyrolysis of water molecules during UV/US hybrid irradiation.

• Journal of Magnetics
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• v.8 no.1
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• pp.1-6
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• 2003

The new class of $Gd_5(Si_xGe_{1-x})_4$ compounds undergoes a simultaneous magnetic/structural phase transition giving a high level of strain that can be induced either by change in temperature or by application of a magnetic field. Profound changes of structural, magnetic, and electronic changes occur in the $Gd_5(Si_xGe_{1-x})_4$ system lead to extreme behavior of the material such as the giant magnetocaloric effect, colossal magnetostriction, and giant magnetoresistance. These unique material characters can be utilized for various applications including magnetic solid refrigerants, sensors, and actuators.

• Journal of the Korea Society of Computer and Information
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• v.20 no.11
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• pp.135-142
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• 2015

This paper applied a VAR model to analyze the effects of RMB exchange rate brought to processing trade, non-processing trade and FDI. Then we can get the results that the appreciation of RMB could not solve the problem of US trade deficit. It is more likely that the appreciation just can transfer the trade imbalance to other country with US, which could not radically solve the economic problems of US. Also this paper find that the data of service trade is surplus while the main goods deficit was occur in advanced technology product, especially in the information & communications trade And US has real advantage in these industries, so the situation will be changed if US decreased the barrier in these industries. In that way, the imbalance situation should be greatly reduced.

• Ocean policy research
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• v.33 no.2
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• pp.1-23
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• 2018

The import control provision of US MSA (Magnuson-Stevens Fishery Conservation and Management Act) IUU fishing is similar to that of MMPA (The Marine Mammal Protection Act of 1972 as Amended) which caused US-Tuna(1991) case. This paper examines whether MSA's import control provision can be found to be inconsistent with WTO agreement. There is no doubt that MSA violates the Article XI:1 of the GATT 1994. The only remaining issue is whether US IUU fishing product measure is justified by the Article XX(g) and its Chapeau. However, Article XX(g) provides for a limited and conditional exception from obligations under other provisions. This paper concludes that the US MSA measure can not be justified under Article XX.

• Korean Journal of Anesthesiology
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• v.71 no.6
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• pp.430-439
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• 2018

In infants and small children, ultrasound (US) guidance provides ample anatomical information to perform neuraxial blocks. We can measure the distance from the skin to the epidural space in the US image and can refer to it during needle insertion. We may also visualize the needle or a catheter during real-time US-guided epidural catheterization. In cases where direct needle or catheter visualization is difficult, US allows predicting successful puncture and catheterization using surrogate markers, such as dura mater displacement, epidural space widening due to drug injection, or mass movement of the drug within the caudal space. Although many experienced anesthesiologists still prefer to use conventional techniques, prospective randomized controlled trials using US guidance are providing increasing evidence of its advantages. The use of US-guided regional block will gradually become widespread in infants and children.

• Journal of IKEEE
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• v.16 no.3
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• pp.159-166
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• 2012

In this paper, we designed and implemented the MIMO (Multiple-Input Multiple-Output) antenna for the mobile handset that could be used for multiple services. Simulation results were obtained using SEMCAD X by SPEAG based on the FDTD (Finite Difference Time Domain) Method which showed that S11 values were less than -6 dB (VSWR < 3) for LTE (Long Term Evolution) 700/2300/2500, K-PCS (Korea-Personal Communication Service : 1,750 ~ 1,870 MHz), US-PCS (US-Personal Communication Service : 1,850 ~ 1,990 MHz), Wibro (2,300 ~ 2,390 MHz), Bluetooth (2,400 ~ 2,483 MHz), and US-WiMAX (US-World interoperability for Microwave Access: 2,400 ~ 2,590 MHz) frequency bands. Measured results of the fabricated antenna also showed that it could be used for LTE 700/2300/2500, K-PCS, US-PCS, Wibro, Bluetooth, and US-WiMAX. services.