Influence of Feed Velocity on Nonlinear Dynamics of Turning Process

An Wang,Wuyin Jin 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.6

A more comprehensive orthogonal turning model is developed in order to further study the influence of feed velocity on frictional chatter. Nonlinear dynamic behavior of the cutting tool in two directions is presented by using bifurcation diagram, phase portrait, and Poincare section. It can be found that the cutting tool has a variety of dynamic behaviors at different feed velocity and cutting velocity, such as periodic motion, quasi-periodic motion, and chaotic motion. Furthermore, the vibration displacement of the cutting tool is affected by the feed velocity, especially for relatively high feed velocity which will result in the cutting tool vibration displacement increase in the cutting direction but a decrease in the feed direction. In addition, it is clear that the stick–slip phenomenon only appears in the cutting direction in our work.

MicroRNA-362 Inhibits Cell Proliferation and Invasion by Directly Targeting SIX1 in Colorectal Cancer

Jin’e Wan,Jian Yang,Cuixia Qiao,Xiaomei Sun,Aiting Di,Lize Zhang,Dandan Wang,Gang Zhao 연세대학교의과대학 2019 Yonsei medical journal Vol.60 No.5

Purpose: Colorectal cancer (CRC) is the third most common cancer in China and poses high morbidity and mortality. In recentyears, increasing evidence has indicated that microRNAs played important functions in the occurrence and development of tumors. The purpose of this study was to identify the biological mechanisms of miR-362 in CRC. Materials and Methods: Quantitative real-time PCR was carried out to assess the expression of miR-362 and SIX1. The Kaplan-Meier method was employed to evaluate the 5-year overall survival of CRC patients. The proliferative and invasive abilities of CRCcells were assessed by MTT and transwell assays. Results: miR-362 was significantly decreased in CRC tissues and cell lines, compared to the normal tissues and normal cells. Asignificant connection was confirmed between the overall survival of 53 CRC patients and low expression of miR-362. Downregulationof miR-362 inhibited the proliferation and invasion through binding to the 3'-UTR of SIX1 mRNA in CRC. Additionally, wediscovered that SIX1 was a direct target gene of miR-362 and that the expression of miR-362 had a negative connection with SIX1expression in CRC. SIX1 could reverse partial functions in the proliferation and invasion in CRC cells. Conclusion: miR-362 may be a prognostic marker in CRC and suppress CRC cell proliferation and invasion in part through targetingthe 3'-UTR of SIX1 mRNA. The newly identified miR-362/SIX1 axis provides insight into the progression of CRC.

矮小條蟲(Hymenolepis nana)에 대한 Albendazole의 영향에 관한 電子顯微鏡的 硏究

王辰聲,金洙鎭,林漢鍾 고려대학교 의과대학 1987 고려대 의대 잡지 Vol.24 No.3

Newly developed albendazole (Zentel®) is a broad spectrum anthelmintic with high activity against intestinal nematodes as well as trematodes and cestodes infections. The present study was undertaken to observe the morphological changes of Hymenolepis nana which obtained from experimentally infected mice after treatment with albendazole. For this study 20 mice were artificially infected with eggs and 16 of them were given albendazole (1×100mg/kg) four weeks after infection. The worms were collected from the small intestine of the mice which were autopsied at 1 and 2 hours after treatment. The fine structure of the collected worms were studied by means of scanning and transmission electron microscopies. The findings were compared with those of untreated worms. The results are as follows: 1. The worms obtained from non-treated mice showed that the whole surface is covered with many microtriches. Microtriches of H. nana may be divided into three anatomical regions; a base, junctional region and cap. Tegumental layer showed well developed syncytium which included a lot of number of discoidal secretory bodies. 2. Many blebs were formed on the surface of the damaged tegument of the worm at 1 hour after treatment with albendazole. The bleb was packed by plasma membrance and included matrix which uniform electron density. Some bleb surface has microtriches. 3. The destruction of tegumental syncytium was recognized at 2 hours after treatment with albendazole. Therefore the blebs on the worm sufrace caused to the death by the tegumatal bursing.

알코올이 Dynamic Posturography에 미치는 영향

이진춘,고의경,장민호,이병주,백무진,노환중,왕수건,전경명 대한이비인후과학회 1999 대한이비인후과학회지 두경부외과학 Vol.42 No.2

운동성 산화 스트레스와 항산화비타민의 보충이 말초단핵세포의 NF-kB 활성에 미치는 영향

진영수,박건구,박준영,김미정,이왕록,김혜영,이한준,박은경 대한스포츠의학회 2000 대한스포츠의학회지 Vol.18 No.2

Reactive oxygen species(ROS) are implicated in the pathogenesis of a wide variety of human diseases. Numerous studies indicate that ROS may serve as common intracellular molecules that contribute to the process of nuclear factor(NF)κB activation in response to a diverse stimuli. In our laboratory, we have demonstrated tat antioxidants could reverse the decline of immune function caused by exercise-induced ROS. Furthermore, it in necessary to understand a mechanism underlying ROS-dependent disorder in biological system. Recent studies have been shown that several gene expression were regulated by oxidants, antioxidants and other determinants of the intracellular reduction-oxidation(redox) state. In this process, NF-κB have been shown to play a important role. The purpose of the present investigation was to evaluate the effect of exercise-induced oxidative stress and antioxidnt supplementation on NF-κB activation in peripheral mononuclear cells. Forty male SD rats(4 weeks old) were randomly divided into noraml diet group and antioxidants(ATO) supplement group, and then ATO groups were treated with antioxidants(VE: 2001U/kg, VC: 50mg/rat, β-carotene: 300mg/kg, vitamin B6: 250㎍/100g, selenomethionine: 0.1mg/kg) for 16 weeks. After 16 weeks breeding at each condition, each group divided into two groups: Control group(CR) fed generally, Exercise group(CE) fed generally and followed by acute exercise 16 weeks later. Antioxidant Antioxidants and Exercise group(AE) fed with antioxidants and followed by acute exercise. The activation of NF-κB binding activity was increased after exhaustive exercise bout in both group. In addition, pretreatment of ATO group with the antioxidants mixture lead to the inhibition of NF-κB binding activity. This results suggest that NF-κB activation should be further studies in response to a variety of exercise.

중국 다문화 교육 탐색 : 중학교 음악교과서를 중심으로

왕금령,오경희 한국문화교육학회 2010 문화예술교육연구 Vol.5 No.3

본 연구는 중국 중학교 음악교과서에서 다문화주의의 반영 정도를 알아보는데 목적을 두고 있다. 이에 중국 중학교 음악과 악보 교과서를 분석하였다. 분석 대상은 중학교 전 학년(1, 2, 3학년) 악보 교과서에 실린 모든 음악과 삽화이다. 음악의 경우, 장르 구별 없이 예를 들면, 민족음악, 대중음악, 종교음악 등 교과서에 실려 있는 모든 곡들을 대상으로 중국 내부 소수 민족별로, 외국별로 분석하였다. 삽화의 경우, 삽화에 나타난 외국의 대표적 작곡가, 음악 등에 대한 소개, 외국의 전통 복장, 외국의 대표적 건물, 풍경, 바다 등, 중국 소수민족, 외국 악기에 대한 소개를 중심으로 분석하였다. 분석결과 첫째, 음악의 경우, 중국 자국 내에 소수민족 음악은 교과서에 어느 정도 반영되어 있으나 55개의 소수민족 음악 중에서 주로 신강 위구르족, 몽골족, 카자흐족, 티베트족, 포이족, 묘족, 백족, 태족, 이족, 요족, 납서족인 11개 민족에 편중되어 있었다. 그리고 외국 음악은 5대륙 지역의 음악이 모두 실려 있으나 분포가 균형적이지 않았으며 특히 유럽 지역의 음악을 중심으로 편중되어 나타났다. 둘째, 삽화의 경우, 외국 작곡가에 대한 소개는 총 13회, 외국의 상징적 물건 총 27희, 소수민족 인물상 종 14회로 나타났다. 이와 같은 분석들을 통해, 무엇보다 다민족으로 이루어진 중국 내에서의 다양한 문화의 공존을 존중하는 배움의 기희가 학생들에게 제공되어져야 함을 촉구하고자 한다. The purpose of this study is to explore the degree of multicultural education reflected in music textbooks of Chinese middle school. The analytic objects are all the music and illustrations appeared in three textbooks. The case of music, ethnic music and foreign music were analyzed. The case of illustrations, representatives of foreign writers, representative works, traditional clothing, and other landmark buildings, natural scenery, China's ethnic minorities, foreign musical instruments. The results are as follows: the first, the case of music, although Chinese minority music were reflected to some degree, focus mainly on the Uygur, Mongolian, Tibetan, Buyi and Miao ethnic music. Regarding foreign music, although the music of five continents appeared in the textbooks, very unevenly distributed and put emphasis on the European music. The second, the case of illustrations, the introduction of foreign musicians appeared 13 times in total; The symbolic construction of foreign appeared 27 times, China's 14 ethnic minority figure appeared. Through these analysis, it can help students understand the cultural diversity of China in music textbooks.

Polylysine을 입힌 배양면이 GH₃ 뇌하수체 종양 세포에 미치는 영향에 관한 연구

김정진,백상호,황덕호,황영일,이왕재,이병란 대한해부학회 1998 Anatomy & Cell Biology Vol.31 No.3

ZnO 박막의 전기 및 광학적 성질

왕진석 충남대학교 공업교육연구소 1982 論文集 Vol.5 No.1

This paper deals with electrical and optical properties of ZnO thin films and show that ZnO films deposited by rf sputtering can be brought almost within the desired conductivity range for opto-electronic devices. The resistivity of ZnO film is about 10^-2Ωcm and transmission over visible range is about 80%.

Si의 드라이 에칭의 영향

왕진석 충남대학교 공업교육연구소 1985 論文集 Vol.8 No.1

Ion beam etching of silicon with N₂and Ar gas has been found to cause the band edge to bend downward near the surface of p-type silicon. Rectifying, rather than ohmic contacts are obtained on p-type silicon. These resalts are to be caused by ion beam etching of silicon. An annealing study revealed that that the damage can be annealed out at relatively high temperature.

중공사 형태의 막여과 공정에서 압력 강하 및 에너지 소비에 관한 연구

왕진수,김병직 崇實大學校 生産技術硏究所 1995 論文集 Vol.25 No.2

Pressure difference is required to purity the untreated water in a membrane-based process. It affects the initial cost and operating cost of the system. Generally, the greater the pressure difference is, the more expensive the water filtration system is. From the experimental data and the derived equations, several design parameters that affect the pressure drop were investigates. The effect of temperature, crossflow velocity, and internal diameter of a fiber on the pressure drop was studied. Within the temperature range of 0℃ to 40℃, as feed water temperature increased, pressure drop required to purify the quantity of the untreated water decreased. And as the crossflow velocity increased, the pressure drop increased. The diameter of 1mm was thought to be a critical size. Below that size, as decreasing the diameter the pressure drop increased sharply. On the other hand, above that size, the pressure drop did not change much with increasing the diameter. Also, the energy cost to produce 1 ton of water was calculated for various modes of membrane-based water treatment systems.