Effect of Iliac Vein Stent with Crown on Flow Field of Bifurcation

WenYing,Haiquan Feng,Xiaoqiang Li,Xiaotian Wang,Ping Cao,Yonggang Wang 한국유체기계학회 2020 International journal of fluid machinery and syste Vol.13 No.2

Interference in blood flow at bifurcation after stent implantation is one of the important causes of thrombosis. Therefore, it is necessary to research the effects of stent structure and implantation position on hemodynamics. Computational fluid dynamics and experimental comparative research methods were used to analyze the influence of stent structure and position of stent on exit velocity, pressure difference between inlet and outlet, higher and lower wall shear stress areas and contralateral flow field. It is indicated in the research that the effect of iliac vein stent implantation on the flow velocity and pressure distribution at the outlet is not obvious, but stent implantation has an influence on the proportion of low wall shear stress and high wall shear stress area in the iliac vein. The low wall shear stress area is inversely proportional to the height of the stent. After stent is implanted, proportion of the high wall shear stress area will decrease, but the degree of decline is not obvious. As the height of stent is increased, the disturbing effect of stent on contralateral blood flow becomes more pronounced. In addition, it is confirmed by the experiments in vitro and in vivo that stent with crown would effectively reduce the interference to the contralateral flow field and the risk of thrombosis and restenosis. Finite element analysis provides effective theoretical support for studying the influence of iliac vein stent implantation on blood flow field.

한국어교육을 위한 주체높임 ‘-(으)시-’의 중국어 대응 양상 연구 : 드라마 병렬말뭉치를 중심으로

설문영 ( Xue¸ Wenying ),김선정 ( Kim¸ Sunjung ) 인하대학교 교육연구소 2020 교육문화연구 Vol.26 No.6

본고의 목적은 드라마 병렬말뭉치(parallel corpus)를 통해 한국어의 주체높임이 실현되는 가장 대표적인 방법인 선어말어미 ‘-(으)시-’가 중국어에서 어떻게 실현되는지 그 양상을 살펴보는 데 있다. 한국어에서는 문법적으로 높임 체계가 발달되어 있고, 중국어에서는 어휘 중심으로 높임을 표현하는데 이러한 양 언어의 차이로 인해 중국인 한국어 학습자가 한국어 높임법을 배울 때 겪는 어려움이 크다. 그중에서도 주체높임은 상대높임보다 상대적으로 덜 복잡하기는 하나 중국인 한국어 학습자들은 이를 사용할 때 여전히 적지 않은 오류를 범한다. 연구 결과, 드라마 병렬말뭉치에서 3,685회 나타나는 한국어 주체높임 선어말어미 ‘-(으)시-’가 중국어로 번역될때 대응되는 높임 표현이 전혀 나타나지 않는 경우가 1,413회로 1/3이 넘는 38.3%에 이르렀음을 알 수 있었다. 또한 대응되는 표현이 나타난다고 하더라도 규칙성을 찾기가 쉽지 않음을 알 수 있었다. ‘啊, 吧, 吗, 呢, 呀’ 등의 어기조사 사용이 높임 표현이 나타나지 않는 경우와 비슷한 비율(35.6%)을 보였고, 의문문의 경우에는 한국어에는 없던 2인칭 대명사 ‘您’을 사용하는 경우가 544회로 14.7%, 명령문의 경우 ‘请’을 사용하여 표현하는 경우가 361회(9.7%)로 나타났다. 또한 동사를 중첩해 표현하기도 하고, 고정 표현이나 높임의 뜻을 가지고 있는 어휘로 대응되기도 하였다. 그러나 모두가 1% 미만의 출현 양상을 보였다. 이는 현대 중국어에서 높임 표현이 점차 사라지고 있는 데다가 높임 표현을 쓰지 않음으로 대화참여자 간의 관계가 가까움을 표현하는 경향이 있기 때문인 것으로 보인다. 본 연구를 통해 도출된 결과는 중국인 한국어 학습자를 위한 주체높임법 ‘-(으)시-’에 관한 교육 자료로 활용될 수 있을 것으로 본다 The purpose of this paper is to examine how the subject honorific pre-ending suffix ‘-(으)시-’, which is the most representative method of realizing Korean subject honorific through the drama parallel corpus, is realized in Chinese. This is a grammatically developed system of honorifics in Korean, and vocabulary-centered honorifics in Chinese. Due to the difference between these two languages, Chinese Korean learners have a great deal of difficulty when learning how to use Korean honorifics. Among them, the subject honorific is relatively less complex than other honorifics, but Chinese Korean learners make a number of errors in using it. As a result of the study, it was found that when the Korean subject-honorific pre-ending ending suffix ‘-(으)시-’, which appears 3,685 times, appeared without a corresponding honorific expression when translated into Chinese in dramas, it was 1,413 times, reaching 38.3%, over 1/3. In addition, it could be seen that even though the corresponding honorific expression appeared, it did not show regularity. The use of particles such as ‘啊, 吧, 吗, 呢, 呀’ was shown in the same proportion as the case where no expressions appeared. In the case of questionable sentences, 544 cases of using the second person pronoun ‘您’, which were not found in Korean, were used in 14.7%, and for imperative sentences, 361 times (9.7%) were expressed using ‘请’. In addition, it can be seen that verbs are overlapped, and the fixed honorific vocabulary is used. However, except for the use of particles such as ‘啊, 吧, 吗, 呢, 呀’, 1,413 times (35.6%), all showed less than 1% appearance. This seems to be due to the fact that the expression of honorifics is gradually disappearing in modern Chinese, and there is a tendency to express that the relationship between participants in the conversation is close by not using the expression of honorifics. The results derived through this study are expected to be used as educational materials on the subject-honorific pre-ending suffix ‘-(으)시 -’ for Chinese Korean language learners.

Research of the Mechanism of Low Frequency Oscillation Based on Dynamic Damping Effect

Wenying Liu,Rundong Ge,Dandan Zhu,Weizhou Wang,Wei Zheng,Fuchao Liu 대한전기학회 2015 Journal of Electrical Engineering & Technology Vol.10 No.4

For now, there are some low frequency oscillations in the power system which feature low frequency oscillation with positive damping and cannot be explained by traditional low frequency oscillation mechanisms. Concerning this issue, the dynamic damping effect is put forward on the basis of the power-angle curve and the study of damping torque in this article. That is, in the process of oscillation, damping will dynamically change and will be less than that of the stable operating point especially when the angle of the stable operating point and the oscillation amplitude are large. In a situation with weak damping, the damping may turn negative when the oscillation amplitude increases to a certain extent, which may result in an amplitude-increasing oscillation. Finally, the simulation of the two-machine two-area system verifies the arguments in this paper which may provide new ideas for the analysis and control of some unclear low frequency phenomena.

SUSTAINABLE LUXURY, BRANDING AND COMPETITIVENESS: THE REVIVIAL OF THE TAILORING CRAFT IN RELATIONAL PRODUCTION NETWORKS

WenYing Claire Shih,Konstantinos Agrafiotes 글로벌지식마케팅경영학회 2015 Global Fashion Management Conference Vol.2015 No.06

Compelling evidence suggests that the Earth’s resources deplete fast and the fashion industry from mainstream to luxury is also partly responsible to this environmental deterioration. The model of fashion production based on global supply chains for cheaper production locations and consumption where speed and endless diversification cater for global demand can hardly be described as sustainable and luxury is no exception to this. The thorny issue in the current state is how to reconcile sustainability which by definition opposes wasteful production and consumption with competitiveness which is built on aggressive models of global brand domination. The authors argue that the craft practices of the tailoring institutions of Savile Row in London constitute an important sustainable luxury example. The tailors have managed remarkably to combine sustainability and competitiveness in a relational model of competition and cooperation.

Construction of rough and porous surface of hydrophobic PTFE powderembedded PVDF hollow fiber composite membrane for accelerated water mass transfer of membrane distillation

Wenying Shi,Tengfei Li,Mengjie Fan,Hongbin Li,Haixia Zhang,Xiaohong Qin 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.108 No.-

The construction of rough and porous hydrophobic membrane surface is expected to overcome the obstaclesincluding low permeate water flux and membrane pore wetting which greatly restrict the developmentof membrane distillation (MD) technology. In this study, a rough and porouspolytetrafluoroethylene (PTFE) powder-embedded polyvinylidene fluoride (PVDF) hydrophobic coatinglayer was compounded on the outer surface of PVDF hollow fiber support membrane by the dilute solutioncoating-phase inversion method. PVDF hollow fiber support membrane was fabricated by the dry-jetwet-spinning technique. PTFE powder was directly incorporated in PVDF dilute coating solution andembedded in the porous PVDF coating layer after the nonsolvent induced phase separation (NIPS). Thevariations of membrane morphology, surface chemical compositions, hydrophobicity and wetting resistancewere investigated by scanning electron microscope (SEM), Attenuated total reflection-Fouriertransform infrared spectroscopy (ATR-FTIR), dynamic water contact angle (WCA) and liquid entry pressure(LEP) analysis. Membrane separation performance including desalination and ionic dyes removalproperties was evaluated by VMD experiment. Compared with PVDF hollow fiber support membrane,both the surface hydrophobicity and the water permeability of the PTFE powder-embedded PVDF hollowfiber composite membrane (HFC) had obvious improvement. The surface WCA and permeate water fluxincreased from 92.6 and 11.3 kg/m2.h for PVDF support membrane to 133.6 and 26.8 kg/m2.h for thePTFE powder-embedded HFC membrane meanwhile NaCl rejection can be maintained above 99.9%(3.5 wt% NaCl aqueous solution at 50 C and permeate pressure at 31.3 kPa). The separation performanceof HFC membrane can remain stable without obvious pore wetting during the continuous MD operationfor 36 h. Different from the desalination, porous hollow fiber membrane would adsorb two differentcharged dyes, Congo red (CR) and methylene blue (MB) to a certain extent, resulting in the decrease ofmembrane flux and the change of permeate water quality. Finally, the MD separation mechanism of inorganicsalt, anionic dye and cationic dye by PTFE powder-embedded HFC membrane was proposed.

Continuous biodiesel production from acidic oil using a combination of the acid-, alkali-catalyzed membrane and GO/PVDF separation membrane

Wenying Shi,Tengfei Li,Hongbin Li,Qiyun Du,Haixia Zhang,Xiaohong Qin 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.107 No.-

An integrated process of esterification with phosphotungstic acid/poly (ether sulfone) (PWA/PES) membrane,transesterification with alkalized polysulfone (APSF) membrane and Graphene Oxide/poly (vinylidenefluoride) (GO/PVDF) separation membrane was carried out to produce biodiesel from acidic oil. Atthe first step, the PWA/PES membrane was introduced to catalyze the esterification reaction. The morphology,maximum pore size, porosity and catalytic esterification performance of PWA/PES membranewere investigated. After the esterification, products and reactants without reaction were put into theGO/PVDF separation membrane to soybean oil and other substances. The permeation mixture flux andsoybean oil rejection of the GO/PVDF separation membrane is 597.89 L/m2h and 98.02%, respectively. At the second step, the APSF membrane was added to catalyze the transesterification reaction in whichthe soybean oil reacted with methanol. The results showed that the esterification conversion was 98.6%and transesterification conversion was 91.2%. The main parameters of the biodiesel product obtainedmeet the Chinese Standard (GB/T 20828) and European Standard (EN 14214).

Role of Autophagy in the Control of Body Metabolism

Wenying Quan,이명식 대한내분비학회 2013 Endocrinology and metabolism Vol.28 No.1

Autophagy plays a crucial role in the maintenance of cellular nutrient balance and the function of organelles such as mitochondria or the endoplasmic reticulum, which are important in intracellular metabolism, insulin release, and insulin sensitivity. In the insulin-producing pancreatic β-cells, autophagy is important in the maintenance of β-cell mass, structure, and function. Mice with deficiencies in β-cell-specific autophagy show reduced β-cell mass and defects in insulin secretion that lead to hypoinsulinemia and hyperglycemia but not diabetes. However, these mice developed diabetes when bred with ob/ob mice, suggesting that autophagydeficient β-cells have defects in dealing with the increased metabolic stress imposed by obesity. These results also imply that autophagy deficiency in β-cells could be a factor in the progression from obesity to diabetes. Another important function of autophagy is in hypothalamic neurons for the central control of energy expenditure, appetite, and body weight. In addition, mice with autophagy deficiencies in the target tissues of insulin have yielded diverse phenotypes. Taken together, these results suggest that autophagy is important in the control of whole body energy and nutrient homeostasis, and its dysregulation could play a role in the development of metabolic disorders and diabetes.

Role of autophagy in the progression from obesity to diabetes and in the control of energy balance

Wenying Quan,정혜승,Myung-Shik Lee 대한약학회 2013 Archives of Pharmacal Research Vol.36 No.2

Autophagy plays a crucial role in cellularhomeostasis through the degradation and recycling oforganelles such as mitochondria or endoplasmic reticulum(ER) that are closely related to the pathogenesis of diabetes. In pancreatic b-cells producing insulin, autophagyhelps maintain b-cell mass, structure and function. In micewith b-cell-specific deletion of Atg7 (autophagy-related 7),a critical autophagy gene, reduction of b-cell mass andpancreatic insulin content were observed together withimpaired insulin secretory function. Because of suchstructural and functional defects, b-cell-specific Atg7-nullmice showed hypoinsulinemia and hyperglycemia. However,those mice never developed diabetes. Obesity andlipids are physiological ER stressors that can precipitateb-cell dysfunction and insulin resistance. Recent studiesshowed that b-cell-specific Atg7-null mice, when bred withob/ob mice, developed severe diabetes, suggesting thatautophagy-deficient b-cells can handle basal metabolicstress but have problems dealing with increased metabolicstress. Thus, autophagy deficiency in b-cells could be afactor in the progression from obesity to diabetes due to aninappropriate response to obesity-induced ER stress. Autophagy also appears to play a role in the hypothalamiccontrol of energy expenditure, appetite and body weight.Thus, autophagy is important to body and nutrient metabolismin many ways, and its dysregulation could contributeto the pathogenesis of metabolic disorders and diabetes.

The Shear Behavior of Double-superposed Panels Reinforced with Different Shear Connectors

Wenying Zhang,Lianping Yang,Shaole Yu,Junsheng Yan 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.10

The shear behavior of a new type of sandwich structure, double-superposed panels, is investigated by conducting push-out test and finite element analysis in this paper. Experiments have been carried out to characterize the effect on the shear behavior of two different shear connector configurations: truss connector and tic-tac-toe connector. Based on finite element analysis, a parameter study is conducted, with the major parameters considered being the diameter, height and pitch of shear connector. Test results indicate that the delamination between the precast layers and core layer is the main failure mode for all specimens, and the crack formation and crack development between the two interfaces is not in synch. It’s also revealed that the specimens with tic-tac-toe connections present higher ultimate shear strength, as well as better ductility during the process of failure, compared to those with truss connections. The results of the numerical simulations show that the ultimate shear strength and the ductility of both connector configurations increases as the diameter of the shear connector increases; increasement in height of shear connector has a negligible effect on the shear behavior; when the pitch length is increased, the ultimate shear strength of the truss connector specimen increases, which is the inverse behavior of the specimen with tic-tac-toe connector.

Preparation of cMWCNTs-incorporated Hollow Fiber Membrane with Improved Water Flux and Dye Adsorption Properties

Wenying Shi,Hongbin Li,Qiyun Du,Shuo Wang,Haixia Zhang,Xiaohong Qin 한국섬유공학회 2019 Fibers and polymers Vol.20 No.2

Carboxylated multi-walled carbon nanotubes (cMWCNTs) were incorporated in membrane matrix during the drywet spinning process to improve membrane performance. Membrane surface composition and morphology were examined by means of FTIR and SEM. The effects of cMWCNTs content on membrane surface hydrophilicity, separation performanceand dye adsorption properties were well investigated and characterized through WCA examination, the cross-flow filtration measurement and the adsorption experiment. The surface hydrophilicity, the water permeability, solute rejection and dye adsorption properties of the cMWNTs-incorporated hollow fiber membranes have been all improved. When cMWNTs content was 0.3 wt%, the cMWNTs-incorporated hollow fiber membrane obtained the obvious enhanced pure water flux (137.2 L·m-2·h-1, at 0.1 MPa) which was 1.5 times as high as that of the original PSF hollow fiber membrane. The preparedcMWCNTs-incorporated membranes are expected to be used in the treatment of textile dyeing wastewater or employed as the supports of the composite membranes.