Surface-guided radiation therapy is an image-guided method using optical surface imaging that has recently been adopted for patient setup and motion monitoring during treatment. We aimed to determine ...whether the surface guide setup is accurate and efficient compared to the skin-marking guide in prostate cancer treatment. Materials and Methods: The skin-marking setup was performed, and vertical, longitudinal, and lateral couch values (labeled as “M”) were recorded. Subsequently, the surface-guided setup was conducted, and couch values (labeled as “S”) were recorded. After performing cone-beam computed tomography (CBCT), the final couch values was recorded (labeled as “C”), and the shift value was calculated (labeled as “Gap (M-S),” “Gap (M-C),” “Gap (S-C)”) and then compared. Additionally, the setup times for the skin marking and surface guides were also compared. Results: One hundred and twenty-five patients were analyzed, totaling 2,735 treatment fractions. Gap (M-S) showed minimal differences in the vertical, longitudinal, and lateral averages (-0.03 cm, 0.07 cm, and 0.06 cm, respectively). Gap (M-C) and Gap (S-C) exhibited a mean difference of 0.04 cm (p = 0.03) in the vertical direction, a mean difference of 0.35 cm (p = 0.52) in the longitudinal direction, and a mean difference of 0.11 cm (p = 0.91) in the lateral direction. There was no correlation between shift values and patient characteristics. The average setup time of the skin-marking guide was 6.72 minutes, and 7.53 minutes for the surface guide. Conclusion: There was no statistically significant difference between the surface and skin-marking guides regarding final CBCT shift values and no correlation between translational shift values and patient characteristics. We also observed minimal difference in setup time between the two methods. Therefore, the surface guide can be considered an accurate and time-efficient alternative to skin-marking guides. KCI Citation Count: 0
Stable N-heterocyclic carbenes (NHCs) have garnered significant attention in synthetic chemistry due to their versatile applications. In this study, we explored a novel mechanochemical method for the ...generation of free carbenes, which could be a good complement to traditional approaches that require strong bases or reductants. Ball milling of NHC–CS2 adducts at room temperature successfully resulted in the quantitative formation of free carbenes that can be subsequently trapped by sulfur or selenium. Importantly, heating NHC–CS2 adducts in solution phase did not lead to the successful generation of free carbenes, in agreement with the high activation energy required for NHC–CS2 dissociation. These findings underscore the potential of ball milling as a robust and versatile approach for generating NHCs from stable NHC-small molecule adducts, and opens new avenues for developing mechanochemical strategies for generating valuable NHC-derived compounds. KCI Citation Count: 0
본 연구는 미-중 패권 경쟁 시대가 지속되는 가운데 중남미 디지털 전환 분야에서 전개되고 있는 중국의 영향력 강화 현상에 대해 중국의 디지털 실크로드 프로젝트와 중남미의 디지털 인프라 및 스타트업 생태계를 중심으로 분석했다. 분석 결과를 요약하면 다음과 같다. 첫째, 중국은 디지털 실크로드 프로젝트를 통해 5G 통신장비 등 IT 제품과 소프트웨어의 ...대중남미 수출 증가, 중국 플랫폼 기업의 중남미 시장 진출 확대, 중국 주도의 디지털 기술표준확산 등을 도모하고 있고, 현재 중남미 33개 국가 중 21개 국가가 중국의 디지털 실크로드프로젝트에 참여하고 있다. 둘째, 디지털 실크로드 프로젝트의 추진에도 불구하고 중국기업의 중남미 디지털 인프라 분야에 대한 진출 성과는 미미한 수준이다. 5G 통신망 구축과 데이터센터 및 클라우드서비스 분야에서 중국기업의 진출이 지속되고 있으나, 미국의 화웨이제재 등으로 중국기업의 중남미 디지털 인프라 분야에 대한 진출이 크게 위축되었다. 셋째, 중국기업의 중남미 스타트업 생태계 진출 성과도 미국기업과 비교해서 미미한 수준이다. 알리익스프레스를 제외하면 중국 빅테크의 중남미 진출 사례가 거의 없고, 중국 벤처캐피털의중남미 스타트업에 대한 투자나 중국 주식시장 상장을 통한 중남미 스타트업의 투자자금 회수사례도 매우 드물다. 마지막으로 이상의 분석 결과를 토대로 종합평가하면, 중국의 대중남미디지털 실크로드 프로젝트는 유의미한 성과를 거두지 못하고 있고 중남미 디지털 전환 분야에서의 중국의 영향력은 미국을 위협할만한 수준에 미치지 못하고 있는 것으로 평가된다. This study aims to analyze China’s rapid digital expansion in Latin America and the Caribbean(LAC) as China’s challenge to American hegemony continues, focusing on China’s Digital Silk Road(DSR) project, LAC’s digital infrastructure and start-up ecosystem. The analysis results are summarized as follows. First, China aims to boost exports of IT products and software, including 5G communication equipment, to LAC through the DSR project. Additionally, China seeks to enhance the presence of its platform companies in the LAC market and exert influence in shaping “standards” in applied digital technologies. Presently, 21 out of the 33 LAC countries are engaged in China’s DSR initiative. Second, despite the expansion of China’s DSR project in LAC, the involvement of Chinese tech companies in LAC digital economies remains limited. Companies like Huawei are establishing mobile infrastructure networks spanning from 2G to 5G and offering data center and cloud services in the region. However, the progression of Chinese tech firms in LAC has significantly slowed down due to U.S. sanctions against Huawei. Third, The involvement of Chinese tech companies in the LAC startup ecosystem is comparatively limited when contrasted with their American counterparts. The presence of major Chinese tech companies in the LAC market is limited, and Chinese venture capital investment in LAC remains modest. Furthermore, startup’s Exit through an initial public offering (IPO) on the Chinese stock market are exceedingly rare. Finally, considering the aforementioned analysis results, it is evaluated that China’s DSR initiative in LAC has not achieved significant success thus far, and China’s influence in the LAC digital transformation has not reached a point where it poses a threat to US hegemony. KCI Citation Count: 0
최근 우리나라에서 연이어 발생한 2016년 경주지진과 2017년 포항지진으로 한반도의 지진 발생 특성을 이해하기 위해 지진학뿐만 아니라 고지진학 분야에서도 연구가 활발하게 수행되고 있다. 고지진학은 과거 지진들에 대한 규모, 변위, 발생시기와 재발주기 등에 대한 유용한 정보를 제공할 수 있다. 또한 최근에는 이에 더하여문화재의 파괴양상을 활용하여 계기지진 ...이전의 역사지진에 대한 발생시기, 규모, 진동의 분포, 진원의 위치에대한 정보를 얻기 위한 고고지진학적 연구도 활발하게 수행되고 있다. 우리나라에서도 일부 학자들에 의해 역사지진기록을 바탕으로 문화재의 피해나 파괴와 역사지진의 연관성에 대한 연구가 수행되었다. 그러나 우리나라의 지체구조적 위치에 기인한 불규칙적인 지진의 발생, 역사지진기록의 모호성, 문화재와 천연기념물 등에대한 직접적인 접근의 제한과 복원 등으로 고고지진학 연구에 많은 제한들이 존재한다. 그럼에도 불구하고 고고지진학은 고지진학, 역사지진, 계기지진자료와 함께 적절히 활용된다면 과거 지진에 대한 정보를 풍부하게할 수 있다. 따라서 문화재의 피해와 역사지진과의 상관성에 대한 더욱 체계적인 분석과 최근 개발된 지진에 의한 환경의 변화에 기초한 진도 산정 방법(ESI scale)을 우리나라의 역사지진 연구에 적절히 적용하여 지속적인연구를 수행한다면 그 동안 간과하였던 역사지진에 의한 피해들이 고고지진학적 새로운 해석을 통해 우리나라지진지질학의 연구에 기여할 수 있을 것으로 기대된다. Recently, various paleoseismological and seismological studies have been conducting for understanding the characteristics of past seismic events after 2016 Gyeongju and 2017 Pohang earthquakes in SE Korea. Paleoseismological studies on past seismic events can provide useful information, such as magnitude, co-seismic displacement, timing and recurrence interval. Furthermore, archaeoseismology, the study of earthquake-related damages in archaeological sites, has recently been used to obtain useful information, such as timing, local intensity, distribution of ground motions, relative location of epicenters, and magnitude for historical earthquakes in many countries. A few researchers have conducted some archaeoseismological studies in Korea to correlate damaged historical heritages with recorded historical earthquakes. However, there are several limitations in archaeoseismological studies in Korea due to irregular occurrences of earthquakes according to the tectonic setting of Korean Peninsula, inaccurate descriptions on historical earthquake records, restriction of direct access to historical heritages and natural monuments, and restoration of cultural properties. Nevertheless, archaeoseismology can improve the knowledge for past earthquakes incorporating with paleoseismology, historical seismology, and instrumental seismology. Therefore, it is possible to obtain useful information on past earthquakes through intensive investigations for comparative study between damaged historical heritages, historical earthquake records and application of ESI scale based on natural environmental effects by earthquakes.
Thus, new interpretations of historical earthquake damages based on archaeoseismology could contribute to the study of earthquake geology of Korea. KCI Citation Count: 4
The solenoid valve for traction control valve (TCV) responsible for the automatic vehicle hold (AVH) function of electric vehicles require a continuous supply of power to the magnetic coil in order ...to operate. When power is continuously supplied, heat is generated because of the resistance of the magnetic coil, which leads to deterioration of the periphery of the solenoid valve and deteriorates durability. To prevent this, when power is applied to the solenoid valve for TCV for more than a certain period of time, the power supply is automatically turned off and the AVH function is controlled to be performed by the electronic parking brake (EPB). In this study, we designed, manufactured, and verified the permanent magnet solenoid valve of TCV for AVH that can minimize unnecessary power consumption of electric vehicle batteries. For the design of the permanent magnet solenoid valve, the location, polarity direction and specifications of the permanent magnet within the solenoid valve were studied through finite element analysis. In order to check whether the braking function by the permanent magnet is maintained even when the current is cut off at AVH’s TCV solenoid valve, electronic control unit (ECU) and electronic stability control (ESC) were manufactured and evaluated for actual vehicle testing. Therefore, it was possible to manufacture a permanent magnet solenoid valve that minimizes unnecessary power consumption of the battery because it does not require power supply even when the car is stopped for a long time in the AVH function of the electric vehicle.
PDF
