http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
이개명,현덕수 濟州大學校 産業技術硏究所 2001 산업기술연구소논문집 Vol.12 No.1
Temperature stabilities of dielectric constants and resonant frequencies of the substrates are very important in piezoelectric ceramics oscillators and filters. In this study. it was investigated temperature stability of the length-extensional vibration mode of Pb(Zr_(y)Ti_(1-y)O_(3)+x[wt%]Cr_(2)O_(3) ceramics. The mode can be utilized in fabricating ultra-small 455kHz IF devices. Addition of Cr_(2)O_(3) in morphotrophic phase PZT decreased the variations of dielectric constant. electro-mechanical coupling factor k_(31) and resonant frequency by thermal shock. As additive weight of Cr_(2)O_(3) increased. the temperature coefficient of resonant frequency changed from positive number to negative one. And the composition with zero temperature coefficient of resonant frequency was shifted to the one with increased Cr_(2)O_(3) additive weight by thermal aging.
이개명,현덕수 제주대학교 산업기술연구소 2001 尖端技術硏究所論文集 Vol.12 No.1
Temperature stabilities of dielectric constants and resonant frequencies of the substrates are very important in piezoelectric ceramics oscillators and filters. In this study, it was investigated temperature stability of the length-extensional vibration mode of Pb(ZryTi1-y)O3 + x[wt%]Cr2O3 ceramics. The mode can be utilized in fabricating ultra-small 455kHz IF devices. Addition of Cr2O3 in morphotrophic phase PZT decreased the variations of dielectric constant, electro-mechanical coupling factor k31 and resonant frequency by thermal shock. As additive weight of Cr2O3 increased. the temperature coefficient of resonant frequency changed from prositive number to negative one. And the composition with zero temperature coefficient of resonant frequency was shifted to the one with increased Cr2O3 additive weight by thermal aging.
분극세기 및 열에이징이 PZT 세라믹스 길이진동모드에 있어서 온도안정성에 미치는 효과
오형철,현덕수,이개명 濟州大學校 情報通信硏究所 2000 情報通信硏究所論文集 Vol.3 No.-
The length extensional vibration mode of a piezoelectric ceramic resonator has the advantage of reduction in its size. In this paper. PZT piezoelectric ceramic specimens with three compositions (Zr/Ti = 56/44, 53/47, 50/50) in Pb(Zr_xTi_(1-x))O₃system were fabricated. We studied effects of poling strength and thermal aging on the vibration mode of the specimens which were poled at 1.5, 2.5, 3.5[KV/㎜] respectively and thermally aged for an hour at 200℃ respectively. The electro-mechanical coupling factor of the length extensional vibration mode increased as poling strength increased. and it decreased after thermal aging. The temperature coefficient of resonant frequency decreased in the 56/44 specimen as poling strength increased after thermal aging. but it increased in the 50/50 specimen. On the conclusion. the changes of poling strength effected on the piezoelectric efficiency and thermal aging contributed to the stabilization of electric dipole structure of the 56/44 specimen.
Lee, Kwang-Hee,Lee, Gae Hwang,Leem, Dong-Seok,Lee, Jiyoul,Chung, Jong Won,Bulliard, Xavier,Choi, Hyeonho,Park, Kyung-Bae,Kim, Kyu-Sik,Jin, Yong Wan,Lee, Sangyoon,Park, Soo Young American Chemical Society 2014 The Journal of Physical Chemistry Part C Vol.118 No.25
<P>The dynamic characterization of two green-sensitive organic photodetectors (OPDs) using nonfullerene small molecules is investigated by analyzing the electrical parameters based on the experimental results and the simulated data. The two OPDs comprise <I>N</I>,<I>N</I>-dimethyl quinacridone (DMQA) as the common donor and dibutyl-substituted dicyanovinyl terthiophene (DCV3T) or boron-subphthalocyanine chloride (SubPc) as respective acceptors. At the applied voltage of −5 V, the device composed of DMQA/SubPc shows a higher frequency response at 148.3 kHz, by 55 kHz higher than the device based on DMQA/DCV3T. The impedance spectroscopy results indicate that the former device exhibits the low resistance due to the high mobility and the low capacitance linked to the dielectric constant. According to the molecular quantum calculation, the linear structure of DCV3T may promote packing of adjacent molecules in the linear direction, resulting in a high polarizability. In contrast, the fused structure of SubPc leads to a decrease in reorganization energy, and its conical shape tends to counterbalance the net dipole at the axial position in the dimer packing configuration owing to the symmetry of the three-branched units in the molecular periphery, which are related to the high carrier mobility and the low dielectric constant. The OPD comprising SubPc, with the dynamic response surpassing the commercialization level of 100 kHz, also exhibits good static performance with an external quantum efficiency of 60.1% at the wavelength of 540 nm, which can be an interesting candidate for potential applications as image sensors.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2014/jpccck.2014.118.issue-25/jp5028788/production/images/medium/jp-2014-028788_0008.gif'></P>
박계수,이준희,이수경,이의주,김달래,송일병,고병희,Park, Gae-Soo,Lee, Jun-Hee,Lee, Soo-Kyung,Lee, Eui-Ju,Kim, Dal-Lae,Song, Il-Byung,Koh, Byung-Hee 사상체질의학회 2007 사상체질의학회지 Vol.19 No.3
1. Objectives This study was carried our to investigate the actual nutrient intake based on Sasang Constitution. 2. Subjects and Methods This study was performed with 984 adults(292 males, 692 females) aged 40 to 69, diagnosed of their Sasang constitution(1 Taeyangin, 242 Soyangin, 492 Taeumin, 249 Soeumin). Data was collected using the Semi-Quantitative Food Frequency Questionnaire. The daily mean nutrient intake and the index for evaluation of quality of nutrient intake were investigated and compared among three constitutional groups(Soyangin, Taeumin, Soeumin) 3. Results and Conclusions The comparisons of the daily mean nutrient intake and the index for evaluation of quality of nutrient intake among three constitutional groups were as followings. (1) In male, the daily mean fat-intake of Taeumin was significantly more than that of Soeumin. In the ratio of car bohydrate-intake in total calorie, Soemuin was significantly higher than the other two groups, and in the ratio of fat-intake lower. %RDA of vitamin B was significantly different among groups. (2) In female, the daily mean fat-intake of Soyangin was significantly more than that of Soeumin. In the ratio of carbohydrate-intake in total calorie, Soemuin was significantly higher than Soyangin, and in the ratio of protein and fat-intake lower. In INQ of protein, Soyangin was significantly higher than Soeumin.
( Gae-eil Jang ),( Won Ho Jang ),( Yang Ki Kim ),( Jung Hwa Hwang ),( Somy Koo ),( Soo Taek Uh ),( Ki Up Kim ),( Bo Young Lee ) 대한결핵 및 호흡기학회 2019 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.127 No.-
Background: Pulmonary thromboembolism is the most preventable but fatal cause of death in hospitalized patients. The main cause of death in pulmonary thromboembolism is right-heart failure due to acute pressure overload. In this sense, extracorporeal membrane oxygenation (ECMO) might be useful in maintaining hemodynamic stability and improving organ perfusion. Some previous studies have reported ECMO as a bridge to definitive therapy of pulmonary thromboembolism. However, little is known about which patients will benefit from ECMO. Methods: Patients who underwent ECMO due to pulmonary thromboembolism at a single university-affiliated hospital between January 2010 and December 2018 were retrospectively reviewed. Results: During the study period, 9 patients were receiving ECMO in high-risk pulmonary thromboembolism. The median age of the patients was 54 years and 6 patients were male. All nine patients had cardiac arrests and ECMO was started as extracorporeal cardiopulmonary resuscitation (E-CPR). One patient received tPA and thrombectomy and one patient underwent thrombectomy as definitive therapy. The others received ECMO as a sole therapy. Two out of nine patients survived. Those survivors had in-hospital cardiac arrests and received ECMO only. Compared to non-survivors, survivors tended to have a short interval between CPR to ECMO initiation (30 minutes vs 60 minutes). Conclusions: Although cardiac arrest before ECMO is known to be a risk factor, early decision to start ECMO and its rapid initiation might help to save those with cardiac arrest in high-risk pulmonary thromboembolism.