A Study of the Yang-gyeong-gyu-il-ui (兩景揆日儀) in the Joseon Dynasty

Lee, Yong Sam,Kim, Sang Hyuk,Mihn, Byeong-Hee The Korean Space Science Society 2015 Journal of Astronomy and Space Sciences Vol.32 No.1

The Yang-gyeong-gyu-il-ui (兩景揆日儀) is a kind of elevation sundial using three wooden plates. Sang-hyeok Lee (李尙爀, 1810~?) and Byeong-cheol Nam (南秉哲, 1817~1863) gave descriptions of this sundial and explained how to use it in their Gyu-il-go (揆日考) and Ui-gi-jip-seol (儀器輯說), respectively. According to Gyu-il-go (揆日考) there are two horizontal plates and two vertical plates that have lines of season and time. Subseasonal (節候) lines are engraved between seasonal (節氣) lines, subdividing the interval into three equal lines of Cho-hu (初候, early subseason), Jung-hu (中候, mid subseason) and Mal-hu (末候, late subseason); there are 13 seasonal lines for a year, thus resulting in 37 subseasonal lines; also, there are 12 double-hour (時辰) lines for a day engraved on these plates. The only remaining artifact of Yang-gyeong-gyu-il-ui was made in 1849 (the $15^{th}$ year of Heon-jong) and is kept at the Korea University Museum. We have compared and analyzed Yang-gyeong-gyu-il-ui and similar western sundials. Also, we have reviewed the scientific aspect of this artifact and built a replica. Yang-gyeong-gyu-il-ui is a new model enhanced from the miniaturization development in the early Joseon Dynasty and can be applied to the southern part of the tropic line through a structure change.

A Study of the Yang-gyeong-gyu-il-ui (兩景揆日儀) in the Joseon Dynasty

Yong Sam Lee,Sang Hyuk Kim,Byeong-Hee Mihn 한국우주과학회 2015 Journal of Astronomy and Space Sciences Vol.32 No.1

The Yang-gyeong-gyu-il-ui (兩景揆日儀) is a kind of elevation sundial using three wooden plates. Sang-hyeok Lee (李尙爀, 1810~?) and Byeong-cheol Nam (南秉哲, 1817~1863) gave descriptions of this sundial and explained how to use it in their Gyu-il-go (揆日考) and Ui-gi-jip-seol (儀器輯說), respectively. According to Gyu-il-go (揆日考) there are two horizontal plates and two vertical plates that have lines of season and time. Subseasonal (節候) lines are engraved between seasonal (節氣) lines, subdividing the interval into three equal lines of Cho-hu (初候, early subseason), Jung-hu (中候, mid subseason) and Mal-hu (末候, late subseason); there are 13 seasonal lines for a year, thus resulting in 37 subseasonal lines; also, there are 12 double-hour (時辰) lines for a day engraved on these plates. The only remaining artifact of Yang-gyeong-gyu-il-ui was made in 1849 (the 15th year of Heon-jong) and is kept at the Korea University Museum. We have compared and analyzed Yanggyeong- gyu-il-ui and similar western sundials. Also, we have reviewed the scientific aspect of this artifact and built a replica. Yang-gyeong-gyu-il-ui is a new model enhanced from the miniaturization development in the early Joseon Dynasty and can be applied to the southern part of the tropic line through a structure change.

한국인 혀동맥의 형태

김희진(KIM Hee Jin),강민규(KANG Mill Kyu),김진학(KIM Jm Hak),박재한(PARK Jae Han),이상섭(LEE Sang Heon),이상헌(LEE Sang Sup),정인혁(CHUNG In Hyuk2) 대한체질인류학회 1997 대한체질인류학회지 Vol.10 No.2

연구자들은 한국인 어른 남녀 시신의 머리와 목 61 을 대상으로 깊은 층 육안해부를 시행하여 혀동맥의 형태를 조사하였다 혀동맥이 일어나는 유형은 위갑상동맥, 혀동맥, 그리고 얼굴동맥이 바깥목동액에서 따로 가지를 내어 나뉘는 경우가 563% 호 가장 않았으며, 얼굴동맥과 혀동맥이 강은 가지에서 얼어나 나뉘는 경우 (312%), 그리고 위 강상동액과 혀동맥이 같은 가지에서 나뉘는 경우 (12 5%) 등이 있었다. 혀동맥과 혀동맥의 둘째 부분은 덮는 목뿔혀근 과의 영대학적 관계는 각각 혀동맥의 첫째 부분이 목뿔혀근 뒤에서 심하게 휘어져 깊은 층으로 들어가는 유형 (41 2 %), 그리고 혀동맥의 첫째 부분이 목뿔혀근의 뒤쪽 근육모셔리 바로 뒤흘 지나 깊은 층으로 들어가는 경우가 661% 로 가장 많았다 목뿔혀근 깊은층에서 혀동맥의 둘째 부분이 달리는 양상은 급하게 위쪽으로 꺾역 달리다가 다시 앞쪽으로 꺾여 혀의 깊은 곳으로 들어가는 경우와 목뿔빼에서 혀쪽으로 완만한 굽이플 이루며 올라가는 경우가 비슷한 반도로 관찰되었다. 입안바닥에 분포하는 혀밑동맥이 혀동맥 셋째 부분에서 나오는 경우슨 전체의 590% 에서만 관창되었으며 그 외는 대부분 얼굴동맥의 턱끝 및동맥 가지가 턱옥뽕근응 옳고 입안바닥에 분포하였다. 따라서 연구자들은 한국인 업안바 닥에는 혀동액이 전체의 59%에서만 분포하며 그외는 영굴동액의 턱끝밑동맥 가지 , 그리고 기타 다른 동맥의 가지들이 분포한다는 사실을 확인하였다

A surveys of homoptera pests on Elaeocarpus sylvestris

Sung-Hyuk Kang,Ho-Sang Lee,Won Il Choi 한국농약과학회 2018 한국농약과학회 학술발표대회 논문집 Vol.2018 No.10

Kalman Filter-Based Ensemble Timescale with 3- Hydrogen Masers

Lee, Ho Seong,Kwon, Taeg Yong,Lee, Young Kyu,Yang, Sung-hoon,Yu, Dai-Hyuk 항법시스템학회 2020 Journal of Positioning, Navigation, and Timing Vol.9 No.3

A Kalman filter algorithm is used for the generation of an ensemble timescale with three hydrogen masers maintained in KRISS. Allan deviation curves of three pairs of clocks were obtained by a three-cornered hat method and were used as reference curves for determination of parameters of the Kalman filter-based timescale. The ensemble timescale equation of a 3-clock system was established, and the clocks' phases estimated by the Kalman filter were used as the prediction time of each clock in the equation. The weight of each clock was determined inversely proportional to the Allan variance calculated with the clocks' phases. The Allan deviation of the weighted mean was 1.2×10^-16 at the averaging time of 57,600 s. However when we made fine adjustments of the clocks' weight, the minimum Allan deviation of 2×10^-17 was obtained. To find out the reason of the great improvement in the frequency stability, additional researches are in progress theoretically and experimentally.

Symptomatic Isolated Celiac Artery Dissection following Blunt Trauma

Sang Bong Lee,Hyuk Jae Jung,Jae Hun Kim 대한외상중환자외과학회 2019 Journal of Acute Care Surgery Vol.9 No.2

An isolated splanchnic artery injury due to blunt trauma occurs rarely because abdominal vascular injuries are typically associated with injuries to the surrounding abdominal structures, including solid organs or hollow viscus. Of the major abdominal vessels, the celiac artery is the least commonly injured by penetrating or blunt abdominal trauma. Furthermore, a celiac artery dissection due to blunt trauma is rarely reported and there is no clearly defined treatment method, even though endovascular and conservative treatments are accepted widely. On the other hand, endovascular treatment can be challenging if the celiac artery dissection involves its main branch, including the proper hepatic artery, left gastric artery, and splenic artery. This case study presents the treatment experience of a celiac artery dissection involving its main branch following dorsal blunt trauma. Furthermore, conservative treatment is proposed as a treatment option for this rare injury.

Influence of Hot Water Immersion and MAP Pre-treatments on Sterilization and Asparagus Spear Qualities During Cold Storage

Hyuk Sung Yoon,In-Lee Choi,Jae-Yun Heo,Ju Young Kim,Su Jeong Han,Ho-Min Kang 한국원예학회 2018 원예과학기술지 Vol.36 No.5

The purpose of this study was to determine how asparagus spear qualities are affected by hot water immersion (HWT) and modified atmosphere packaging (MAP) pre-treatments. Asparagus spears were treated either with different durations of HWT or packed with 10,000 cc/m²·day·atm oxygen transmission rate (OTR) film as the MAP treatment, and then stored at 4°C until the final storage day. Respiration and ethylene production rates in asparagus increased after HWT, with 8 and 16 min treatments having the most effect on these parameters. Fresh weight loss was less than 0.3% with all treatments. Gas composition (i.e., C₂H₄, CO₂, and O₂) within the packaging was not significant among all treatments during storage. The MAP and HWT treatments made no difference not only in fresh weight but also in gas composition. Microbial growth (i.e., total aerobic bacteria, yeast, mold, and E. coli) was lower with the 2 and 4 min treatments than with the other treatments. Electrolyte leakage was less in the control, 2 min, and 4 min treatments compared to the 8 and 16 min treatments. The hue angle and total chlorophyll values, which are associated with yellowing, remained constant at the 2 and 4 min treatments compared to the other treatments, which did not have maintained values. Asparagine content accumulated in the control, 2 and 4 min treatments, whereas the 8 and 16 min treatments showed a decrease in asparagine content. Stem firmness was similar to pre-storage measurements with the 4 min treatment. Stem length for all of the treatments was slightly increased before storage regardless of HWT duration. Asparagus off-odor and visual qualities were the best with 4 min treatment compared to the other treatments. Consequently, HWT for 2-4 min and MAP Pre-treatments were effective in maintaining the measured qualities among the treatment and control groups. In contrast, HWT for more than 8 min offset any beneficial heat-treatment effects for long-term storage; as indicated by tissue softening at the stem tip, which resulted in secondary damages that included microorganism infection and deterioration of visual quality in the vegetables.

A Study on the Obstacle Collision Detection for Ensuring of Gait Stability of Transfemoral Prosthesis Users

Sang Hyun Lee,Su Hong Eom,Mun-Seok Jang,Eung Hyuk Lee 한국재활복지공학회 2018 한국재활복지공학회 학술대회논문집 Vol.2018 No.11

Transfemoral prosthesis is an assistive device that enables gait of below-knee amputees. Transfemoral prosthesis are largely divided into active powered and passive types depending on the control method. Currently, active powered transfemoral prosthesis support various gait environments by improving the disadvantages of transfemoral prosthesis. Active powered transfemoral prosthesis estimate the gait environment and conditions through the acquired gait information by measuring the motion state of the knee joint through inertia sensors and the ground reaction force through a load cell. However, these advanced active powered transfemoral prosthesis still have functional limitations in reacting to dangerous situations. Therefore, this study classifies collision types using inertia sensors which arc effective for estimating the motion and impulse among the sensors mounted in existing active powered transfemoral prosthesis, which can be used in prosthetic systems. Furthermore, to change the response method depending on the impulse, the dangerous situations in the event of a collision were classified through an extended support vector machine (SVM). Experiments were conducted with 5 persons of 70 ㎏ and 10 persons of 80 ㎏, and the dangerous situations were classified in accordance with each collision type.

Is higher dose always the right answer in stereotactic body radiation therapy for small hepatocellular carcinoma?

Lee, Kyung Hwa,Yu, Jeong Il,Park, Hee Chul,Park, Su Yeon,Shin, Jung Suk,Shin, Eun Hyuk,Cho, Sungkoo,Jung, Sang Hoon,Han, Young Yih,Lim, Do Hoon The Korean Society for Radiation Oncology 2018 Radiation Oncology Journal Vol.36 No.2

Purpose: This study was conducted to compare clinical outcomes and treatment-related toxicities after stereotactic body radiation therapy (SBRT) with two different dose regimens for small hepatocellular carcinomas (HCC) ${\leq}3cm$ in size. Materials and Methods: We retrospectively reviewed 44 patients with liver-confined HCC treated between 2009 and 2014 with SBRT. Total doses of 45 Gy (n = 10) or 60 Gy (n = 34) in 3 fractions were prescribed to the 95% isodose line covering 95% of the planning target volume. Rates of local control (LC), intrahepatic failure-free survival (IHFFS), distant metastasis-free survival (DMFS), and overall survival (OS) were calculated using the Kaplan-Meier method. Results: Median follow-up was 29 months (range, 8 to 64 months). Rates at 1 and 3 years were 97.7% and 95.0% for LC, 97.7% and 80.7% for OS, 76% and 40.5% for IHFFS, and 87.3% and 79.5% for DMFS. Five patients (11.4%) experienced degradation of albumin-bilirubin grade, 2 (4.5%) degradation of Child-Pugh score, and 4 (9.1%) grade 3 or greater laboratory abnormalities within 3 months after SBRT. No significant difference was seen in any oncological outcomes or treatment-related toxicities between the two dose regimens. Conclusions: SBRT was highly effective for local control without severe toxicities in patients with HCC smaller than 3 cm. The regimen of a total dose of 45 Gy in 3 fractions was comparable to 60 Gy in efficacy and safety of SBRT for small HCC.

Feature Subset for Improving Accuracy of Keystroke Dynamics on Mobile Environment

( Sung-hoon Lee ),( Jong-hyuk Roh ),( Soohyung Kim ),( Seung-hun Jin ) 한국정보처리학회 2018 Journal of information processing systems Vol.14 No.2

Keystroke dynamics user authentication is a behavior-based authentication method which analyzes patterns in how a user enters passwords and PINs to authenticate the user. Even if a password or PIN is revealed to another user, it analyzes the input pattern to authenticate the user; hence, it can compensate for the drawbacks of knowledge-based (what you know) authentication. However, users' input patterns are not always fixed, and each user's touch method is different. Therefore, there are limitations to extracting the same features for all users to create a user's pattern and perform authentication. In this study, we perform experiments to examine the changes in user authentication performance when using feature vectors customized for each user versus using all features. User customized features show a mean improvement of over 6% in error equal rate, as compared to when all features are used.