http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Sung Woon Moon,김태효,Hyeon Sik Kim,Ji-Hyeon Ju,Yeon Jeong Ahn,Hyun Jeong Jang,심상군,김현진,정운태,이옥재 대한소화기내시경학회 2012 Clinical Endoscopy Vol.45 No.4
Background/Aims: The rapid urease test (RUT) is an invasive method to diagnose Helicobacter pylori infection, which relies on the acquisition and examination of gastric antrum and body tissues. We determined and compared the efficacy of RUT when the tissues were examined separately or after being combined. Methods: Two hundred and fourteen patients were included and underwent esophagogastroduodenoscopy from July 2008 to June 2010. The separate test was defined as evaluating the status of infectivity of H. pylori from the antrum and body separately; whereas the united test was carried out putting both tissues from the antrum and body in the same RUT kit. All RUTs were read by a single observer 1, 3,6, 12, and up to 24 hours later. We also got two biopsy specimens stained with hematoxylin and eosin and quantified H. pylori density was calculated on a scale of 0 to 3. Results: Overall positivity for H. pylori was 137 (64%) for the separate test and 148 (69.2%) for the united test (p<0.01). The mean time to a positive test was 3.58 hours for the separate test and 1.69 hours for the united test (p<0.01). The correlation between the time to positive RUT and the severity of histology showed r=+0.556 for the antrum (p<0.01) and r=+0.622 for the body (p<0.01). Conclusions: Combining tissues prior to RUT enhances the detection of H. pylori, as compared with the examination of separate tissues,and shortens the time to develop a positive reaction by approximately 50%. These diagnostic advantages are also accompanied by increased cost-savings.
Meteoric activities during the 11th century
Blackwell Science Ltd 2005 Monthly notices of the Royal Astronomical Society Vol.358 No.4
<P>ABSTRACT</P><P>We have analysed the meteor records in the chronicles that describe the era of the Song dynasty (<SMALL>AD</SMALL> 960–1279). The data are complementary to the record-vacant 10th century of the Koryo dynasty (<SMALL>AD</SMALL> 918–1392). The annual activity of sporadic meteors analysed shows a generic sinusoidal behaviour as in modern observations. In addition, we have also found that there are two prominent meteor showers, one in August and the other in November, appearing on the fluctuating sporadic meteors. The date of occurrence of the August shower indicates it to be the Perseids. By comparing the date of occurrence of the November shower with those of the Leonid showers of the Koryo dynasty, recent visual observations and the world-wide historical meteor storms, we conclude that the November shower is the Leonids. The regression rate of the Leonids is obtained to be <IMG SRC='http://mnras.oxfordjournals.org/content/358/4/1105/embed/inline-graphic-1.gif'/> days per century, which agrees with recent observations.</P>
Ahn, Sung-Hyeon,Choi, Jae-Won,Jeon, Yong-Chan,Jeong, Chang-Mo,Yoon, Mi-Jung,Lee, So-Hyoun,Huh, Jung-Bo Korean Academy of Dental Science 2017 Journal of korean dental science Vol.10 No.1
Purpose: The purpose of this study was to evaluate the microleakage of various types of resin-bonded fixed partial dentures (RBFPDs) after artificial aging. Materials and Methods: Forty models with missing first molar were fabricated using artificial resin teeth and were divided into four groups: Group A, conventional RBFPDs design; Group B, modified RBFPDs design; Group C, assembled 3-piece RBFPDs design; and Group D, assembled 3-piece RBFPDs with different occlusal rest positions. Half of the specimens underwent chewing simulation process (240,000 cycles, 50 N load, 1.7 Hz) and thermocycling (temperatures $5^{\circ}C{\sim}55^{\circ}C$, dwelling time 30 seconds) and the remaining 20 specimens didn't receive any treatment. All the specimens were immersed in 2% methylene blue solution for 24 hours to evaluate microleakage, and were sectioned at the middle part of abutment teeth. To evaluate the microleaskage, a dye penetration was calculated. Result: With artificial aging, cyclic loading and thermocycling, a 3-piece RBPFD and a 2-piece RBPFD using original tooth undercuts have significantly lower microleakge (P<0.05) compared to the conventional design of RBPFD and modified RBPFD. Conclusion: Within the limit of this experiment, the assembled RBFPDs exhibited a smaller microleakage than the conventional RBFPDs, implying that the assembled RBFPDs can be more effective for reducing the dislodgement of the RBFPDs.
LYα LINE FORMATION IN HUBBLE-TYPE SPHERICAL OUTFLOWS IN STARBURST GALAXIES
AHN SANG-HYEON,LEE HEE-WON The Korean Astronomical Society 2002 Journal of The Korean Astronomical Society Vol.35 No.4
Almost half of primeval galaxies show P-Cygni type profiles in the Ly$\alpha$ emission line. The main underlying mechanism for the profile formation in these systems is thought to be the frequency re-distribution of the line photons in expanding scattering media surrounding the emission source. A Monte Carlo code is developed to investigate the Ly$\alpha$ line transfer in an optically thick and moving medium with a careful consideration of the scattering in the damping wings. Typical column densities and expansion velocities of neutral hydrogen investigated in this study are $N_{H1}{\~}10^{17-20}\;cm^{-2}$ and ${\Delta}V{\~} 100 km\;s^{-1}$. We investigate the dependence of the emergent profiles on the kinematics and on the column density. Our numerical results are applied to show that the damped Ly$\alpha$ absorbers may possess an expanding H I supershell with bulk flow of ${\~}200 km\;s^{-l}$ and H I column density $N_{H1}{\~}10^{19}\;cm^{-2}$. We briefly discuss the observational implications.
Optimal Wrist Design of Wrist-hollow Type 6-axis Articulated Robot using Genetic Algorithm
Hyeon Min Jo(조현민),Won Jee Chung(정원지),Seung Min Bae(배승민),Jong Kap Choi(최종갑),Dae Young Kim(김대영),Yeon Joo Ahn(안연주),Hee Sung Ahn(안희성) 한국기계가공학회 2019 한국기계가공학회지 Vol.18 No.1
In arc-welding applying to the present automobile part manufacturing process, a wrist-hollow type arc welding robot can shorten the welding cycle time, because feedability of a welding wire is not affected by a robot posture and thus facilitates high-quality arc welding, based on stable feeding with no entanglement. In this paper, we will propose the optimization of wrist design for a wrist-hollow type 6-Axis articulated robot. Specifically, we will perform the investigation on the optimized design of inner diameter of hollow arms (Axis 4 and Axis 6) and width of the upper arm by using the simulation of robot motion characteristics, using a Genetic Algorithm (i.e., GA). Our simulations are based on SolidWorks<SUP>®</SUP> for robot modeling, MATLAB<SUP>®</SUP> for GA optimization, and RecurDyn<SUP>®</SUP> for analyzing dynamic characteristics of a robot. Especially RecurDyn<SUP>®</SUP> is incorporated in the GA module of MATLAB<SUP>®</SUP> for the optimization process. The results of the simulations will be verified by using RecurDyn<SUP>®</SUP> to show that the driving torque of each axis of the writs-hollow 6-axis robot with the optimized wrist design should be smaller than the rated output torque of each joint servomotor. Our paper will be a guide for improving the wrist-hollow design by optimizing the wrist shape at a detail design stage when the driving torque of each joint for the wrist-hollow 6-axis robot (to being developed) is not matched with the servomotor specifications.
OBSERVING SITES FOR THE CENTRAL SOLAR ECLIPSES IN ANCIENT CHINESE HISTORY
Ahn, Sang-Hyeon The Korean Astronomical Society 2020 Journal of The Korean Astronomical Society Vol.53 No.6
We determine the observing sites for eclipses of large magnitude recorded in ancient Chinese chronicles from 200 BCE to 900 CE, by adopting the difference between terrestrial time and universal time, ΔT, given by Morrison & Stephenson (2004). The records of solar eclipses with large magnitude are divided into four groups in accordance with the historical variations of the capital cities of ancient Chinese dynasties. We determine areas in which all the eclipses in each group, with an eclipse magnitude larger than a certain threshold value, could be observed. We find that these areas coincide with the historical capitals, which agrees with the general idea that the solar eclipses were observed at the capital of each dynasty. This result also verifies the ΔT values during the period from 100 BCE to 400 CE, during which historical records of eclipses are so rare that the ΔT values can only be obtained by interpolating the long-term data. Moreover, we show that the eclipses described by the term Ji in East-Asian history are not all total eclipses; their mean magnitude is 0.96 ± 0.04. We find that complementary expressions, such as dark daytime and appearance of stars during the eclipse, strengthen the possibility that eclipses described by the term Ji were total. We also provide quantitative definitions for expressions such as 'being not complete and like a hook', 'being almost complete', 'visibility of stars during the eclipse', and 'darkness during an eclipse.' The literal meanings of these expressions are in agreement with the recent physical modeling of sky brightness during total eclipses provided by Können & Hinz (2008).