Ferroelectric and Electrical Properties of Lead-Free (K0.44Na0.52Li0.04)(Nb0.86Ta0.10Sb0.04)O3 Thin Films

Ju Sung Kim,Chang Won Ahn,Amir Ullah,Song A. Chae,Ill Won Kim 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.68 No.12

The Li, Ta, and Sb-substituted lead-free (K0.44Na0.52Li0.04)(Nb0.86Ta0.10Sb0.04)O3 (KNLNTS) thin films were fabricated on Pt(111)/TiO2/SiO2/Si substrates using the radio frequency (RF) magnetron sputtering method. The KNLNTS thin films were annealed at 750 C for 1 h in an oxygen ambient. The film with a thickness of 350 nm exhibited a typical ferroelectric P − E hysteresis loop without fatigue even after 1010 pulses. The KNLNTS thin film exhibited a relatively low leakage current density of 10−7 A/cm2 even up to an applied electric field of 142 kV/cm. A well-saturated piezoelectric hysteresis loop was obtained with a piezoelectric coefficient d33 of 21 pm/V.

충수에서 발생한 선상유암종 1예

김경아,송인성,정현채,송호준,김정룡,김주성,문해,이광혁,김강모 대한소화기학회 1999 대한소화기학회지 Vol.34 No.6

An adenocarcinoid in the appendix is very rare, and its histologic and prognostic features are between those of carcinoid and adenocarcinoma. This report describes the case of a 36-year-old man with an adenocarcinoid in the appendix. Three years prior to admission, he received appendectomy due to right lower quadrant pain. However, a chronic colicky abdominal pain persisted and was aggravated for recent 15 days. Initially, we thought that adhesive ileus caused the pain, but the pain was not relieved by the management. Radiologic studies and endoscopic examination showed that the pain might result not from postoperative adhesive ileus but from another unknown disease. Therefore, operation was performed to find out its definite cause. Small bowel resection and radical right hemicolectomy was carried out to confirm the possibility of malignancy or other inflammatory bowel disease such as tuberculosis. Finally, it was diagnosed as an appendiceal adenocarcinoid with ischemic changes. The ischemic changes were attributed to surrounding fibrosis by appendiceal adenocarcinoid.

햅틱보조설계 기법과 요추각도의 예측을 이용한 의자등판의 인간중심적인 설계

이상덕(Sang-Duck Lee),이해아(Hae-A Lee),송재복(Jae-Bok Song),채수원(Soo-Won Chae) 대한기계학회 2010 大韓機械學會論文集A Vol.34 No.11

인체와의 물리적인 접촉이 수반되는 제품의 설계 및 개발에서 필요한 시제품을 햅틱 시뮬레이터로 대체하는 설계 기법을 햅틱보조설계(Haptics-Adided Design, HAD)라 하는데, 이를 통하여 개발 비용 및 시간을 감소시킬 수 있다. 제품설계에 있어서 사용자의 감성적인 요소뿐만 아니라 제품이 사용자의 신체에 미치는 영향이 중요함에도 불구하고, 기존의 HAD 는 사용자의 감성적인 평가만을 설계에 반영하였다. 그 결과, 사용자가 편하게 느끼는 설계와 인체공학적인 측면에서 권장하는 설계 사이에 차이가 발생하였다. 이와 같은 문제를 해결하기 위하여 본 연구에서는 기존의 HAD 과정에 제품의 사용 시에 사용자의 신체 변화를 관찰하는 단계를 추가하여 인간중심의 설계를 구현할 수 있는 방법을 제안하였다. 제안된 설계방식을 검증하기 위하여, 등판의 강성을 조절할 수 있는 햅틱의자 시뮬레이터를 사용하여 사무용 의자 등판의 틸트구조 설계에 HAD 를 적용하였고, MADYMO 를 이용한 시뮬레이션을 통하여 인체공학적인 측면에서 제품이 올바르게 설계 되었는지 검증하였다. 이를 바탕으로 제안한 설계방법이 감성적인 요소와 신체적인 요소를 모두 실시간으로 설계에 반영할 수 있음을 확인하였다. Haptic-aided design (HAD) involves the use of a haptic simulator in place of physical prototypes in the design and development of products with which human beings interact physically. The development time and cost can be significantly reduced by adopting this HAD scheme. Although both physical and emotional factors are equally important, only the emotional factors were taken into consideration in the previous HAD process. Consequently, the design of the products was sometimes unsatisfactory from the viewpoint of ergonomics, even though users were emotionally satisfied with the products. To overcome this problem, in this study, we propose a new human-oriented design methodology that is enhanced by taking the physical factors into consideration. The HAD scheme was verified by using a haptic chair simulator to design a tilt mechanism of an office chair for which the stiffness of the backrest can be adjusted; then, the design was simulated using MADYMO. The results show that the proposed method can reflect both the physical and emotional factors to modify the design in real-time.

목 건강 고위험군의 움직이는 모니터 사용에 따른 두부전방 자세 교정 효과에 관한 연구

최경희(Kyeong-Hee Choi),공용구(Yong-Ku Kong),심현호(Hyun-Ho Shim ),조민욱(Min-Uk Cho),박채원(Chae-Won Park),홍보람(Bo-Ram Hong),김승훈(Seoung-Hoon Kim),정현주(Hyun-Ju Jung),송현아(Hyun-A Song),류지헌(Ji-Heon Ryu),김재경(Jae-Kyeong Ki 대한인간공학회 2019 대한인간공학회 학술대회논문집 Vol.2019 No.10

Objective: The aim of this study was to verify the correction effect of Forward Head Posture (FHP) by using Moving Monitor in a high-risk group of the neck. Background: Office workers who have been used VDTs are subject to high loads on the neck and shoulders during their work due to the high frequency of FHP. Thus, our research team developed a Moving Monitor Arm that continuously induced calibration movements when the users use the monitor. Method: Seven participants who rated as a high-risk group of the neck to study the effect of FHP correction using the Moving Monitor. The fatigue and posture of the neck were quantified using Flexion Relaxation Ratio (FRR), Onset Angle, Offset Angle, Craniovertbral Angle (CVA) and Subjective Discomfort Rating in this study. Results: The effects of task pre/post on the FRR and subjective discomfort, and the effect of monitor type on the Onset/Offset angles was significant in this study, respectively. Conclusion: Based on the results of the experiment, correction effect of Moving Monitor was verified. Application: The results of this study showed that moving monitors can be applied to prevent musculoskeletal disorders associated with VDTs.

크론병 환자에서 Azathioprine 치료 중 발생한 다형성 지방육종

안수민 ( Soo Min Ahn ),서승오 ( Seong O Suh ),오유미 ( Yu Mi Oh ),윤창용 ( Chang Yong Yun ),심형훈 ( Hyoung Hun Sim ),박채아 ( Chae A Park ),송철민 ( Cheol Min Song ),배지윤 ( Ji Yoon Bae ) 대한소화기학회 2013 대한소화기학회지 Vol.62 No.4

Azathioprine is frequently used for the treatment of inflammatory bowel diseases (IBD) such as Crohn`s disease and ulcerative colitis. Lymphomas, squamous cell carcinomas, and undifferentiated pleomorphic sarcomas have been reported among patients receiving azathioprine therapy. Herein, we report a case of pleomorphic liposarcoma of chest wall which occurred in a 44-year-old man with Crohn`s disease taking azathioprine. He was diagnosed with Crohn`s disease 3 years ago after suffering from abdominal pain and hematochezia for 12 years. He had been taking 50 mg of azathioprine per day for 23 months when he visited the thoracic and cardiovascular surgery clinic due to right chest palpable mass that had rapidly grown during the past 2 months. Excisional biopsy was performed and the mass was diagnosed as pleomorphic liposarcoma. Therefore, he underwent radical excision of the right chest wall mass, which measured 11.0×6.5 cm in size. He is scheduled to receive radiation therapy and chemotherapy. (Korean J Gastroenterol 2013;62:248-252)

논문(論文) : 『식료찬요(食療纂要)』에 나타난 소갈(消渴)의 식치(食治)에 대(對)한 소고(小考)

송지청 ( Ji Chung Song ),김상운 ( Sang Un Kim ),채송아 ( Song A Chae ),엄동명 ( Dong Myung Eom ) 대한한의학원전학회(구 대한원전의사학회) 2012 대한한의학원전학회지 Vol.25 No.3

Objective : 『Sikryochanyo』written by Jeon Soonyi is the first Food-Therapy book at Korea. In『Sikryochanyo』, there are many kinds of food-Therapy including prescriptions for thirst disease. Conception of hirst disease in traditional mendicine contains diabetes in some aspects. One of the Ingeative methods in diabetes limits taking protein but 『Sikryochanyo』 shows several prescriptions including protein. Method : We will try to find out cases of Food-therapy for thirst disease in 『Sikryochanyo』 and classify several prescriptions including protein. Result : In 『Sikryochanyo』, several prescriptions for thirst disease including protein were treated as materia medica widely such as stomach of cow and pig, intestine of pig, head of dear, rabbit, chicken, goose, pheasant, milk and lung of sheep. Conclusion : On several types of prescriptions for thirst disease including protein there are plenty of usage with its own effectiveness.

Rapid and Sensitive Analysis of Valproic Acid in Human Red Blood Cell by LC-MS/MS

Han, Song-Hee,Kim, Yun-Jeong,Jeon, Ji-Young,Hwang, Min-Ho,Im, Yong-Jin,Jeong, Jin-A,Lee, Chang-Seop,Chae, Soo-Wan,Kim, Min-Gul Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.5

A sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed to determine valproic acid in human red blood cell (RBC). It is important to measure the drug concentration of the RBC as well as that of the plasma because of drug partitioning for pharmacokinetic and pharmacodynamic study. The method was linear over the dynamic range of 1-100 ${\mu}g$/mL with a correlation coefficient $r$ = 0.9997. The linearity of this method was established from 1 to 100 ${\mu}g$/mL for valproic acid in red blood cell with accuracy and precision within 15% at all concentrations. The intra-run and inter-run assay accuracy and coefficient of variations are all within 15% for all QC samples prepared in plasma and red blood human samples. Then, valproic acid amount by protein precipitation in plasma was quantified by LC-MS/MS mass spectrometry. The distribution ratio of VPA in RBC and plasma was analyzed by clinical samples. Based on measurement of the valproic acid in human red blood cell, this method has been applied to clinical research for study of distribution ratio of valproic acid in blood.

Large transverse piezoelectric properties of lead-free Bi0.5(Na0.82K0.18)0.5TiO3 films

Song A. Chae,Sung Sik Won,Hae Jin Seog,Aman Ullah,Chang Won Ahn,Ill Won Kim 한국물리학회 2016 Current Applied Physics Vol.16 No.4

The ferroelectric and piezoelectric properties of Bi0.5(Na1-xKx)0.5TiO3 (x ¼ 0, 0.18 and 0.25) films deposited on Pt(111)/TiO2/SiO2/Si(100) substrates using a chemical solution deposition technique were examined as part of an ongoing study into the development of lead-free piezoelectric films. The effective transverse piezoelectric coefficient (e* 31,f) was examined to assess the potential applications of these piezoelectric films for device applications using the Bi0.5(Na0.82K0.18)0.5TiO3 (BNKT18) cantilever, which is the morphotropic phase boundary composition in the Bi0.5(Na1-xKx)0.5TiO3 system. The BNKT18 cantilever showed good linearity of piezoelectric displacement with low hysteresis under an applied field, and exhibited a high effective transverse piezoelectric coefficient (e* 31,f) of ~5.15 C/m2 and a figure of merit ((e* 31,f)2/ε0εr) of 3.8 GPa, which are comparable to the preferred oriented lead-free piezoelectric and lead zirconate titanate thin films. This suggests that the BNKT18 film is a potential candidate for lead-free piezoelectric film devices.

H . pylori 감염에 의하여 유발되는 인체 위상피세포주에서의 Chemokine 유전자의 발현 - 합성 RNA를 이용한 Interleukin-8과 Monocyte Chemotactic Protein-1 mRNA의 정량

정현채(Hyun Chae Jung),김정목(Jung Mogg Kim),김경아(Kyung A Kim),송인성(In Sung Song),김정룡(Chung Yong Kim) 대한소화기학회 1996 대한소화기학회지 Vol.28 No.2

N/A Background/Aims: Despite the prevalent knowledge that Helicobacter pylori is non-invasive, mucosal infiltration of inflammatory cells has been observed in the gastric mucosa. Chemokines have been implicated in a wide range of acute and chronic int1ammatory processes. We tested whether H, pylori-induced inflammation could be triggered by an array of chernokine genes expressed in human gastric epithelial cells. Methods: After the gastric epithelial cel]s, SNU-5, KATO III and Hs746T, and the non-gastric epithelial cells, HCT-8 and HT-29, were infected ivith H. pylori, cellu]ar RNA was extracted by the guanidinium thiocyanate-phenol-chlorofonm method. Expression of severol chemokine genes was assessed using quantitative reverse transcriptional polymerase chain reaction(RT-PCR). Chemokine mRNA was quantified by RT-PCR using specific primers and synthetic standard RNA generated from pHCQ. Results: Interleukin-8(IL-8) mRNA was expressed in gastric epithelial cells throughout the entire infection period. Monocyte chemotactic protein-l (MCP-l) mRNA was expressed in SNU-5 cells after 9 hours of infection. RANTES(regulated on activation, normal T expressed and secreted) wos not expressed in either cell line. In SNU-5 cells, IL-8 mRNA was hiqhly expressed(1.3 >'10 raolecules/(lg total RNA) after 1 hour and reached its peak ]evel(1.0 10 molecules) at 9 hours. In KATO III ce]ls, IL-8 mRAA expression reached the peak level at 4 hours. Gene expression paralleled the amount of IL-8 protein measured by ELISA(enzyme linked immunosorbent assay). IL-S mRNA expression was not observed in KATO III ceIls infected with C. fetus subsp. Fetus, C. jejuni. And nonpatho- genic E. coli DH5a. IL-8 mRNA expression was increased not only in gastric epithelial cells but also in non-gastric cells infected with H. pylori. Conclusions: These results suggest that an inflammatory reaction induced by H. pylori be initially triggered by chernokines expressed in infected gastric epithelial cells. In addition, H. pylori may have a potential to induce inflammatory reactions in non-gastric epithelial cells. (Korean J Gastroenterol 1996; 28:198-210)

현대 화예 작품의 인공성에 관한 고찰 -G. Dickie의 예술의 필요조건으로서의 인공성에 관한 언급을 바탕으로-

채송아 ( Song A Chae ) 한국화예디자인학회 2008 한국화예디자인학 연구 Vol.19 No.-

There have been many discussions regarding modern floral art, especially focusing on the characteristic of its constituent factors and interpretation thereof. In order to discover the identity of the floral arts and to have grasped its essential nature, a great deal of efforts has been exerted. In the end, however, the quest on floral art design starts from such very basic topic as What is art? Thus, in this study, the researcher attempted to establish the identity of floral art design as in a genre of arts having approached the subject from the artistic and philosophical perspective based on the statement regarding artificiality as prerequisite to arts of G. Dicki. Research procedures consist of arrangements of the concept of artificiality of art and its distinct features based on the definitions and theories of art. In order to arrange the theories related to artificiality analyzed in a terse and clear manner, and also to classify thereof, they were represented by signs. Based on these coded materials, the researcher tried to clarify the view on the modern floral art, and to present a structural and in-depth method for interpretation thereof, having analyzed modern floral art works, and put such analytical results into practice with suitable application.