Effect of Al on the Microstructure and Mechanical Properties of Mg–Sn–Ca–Mn Wrought Alloy

Yun Feng,Yuanyuan Yang,Zongqi Xiao,Xianglong Meng,Guorong Zhou,Jinfeng Leng,Xinying Teng 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.6

Mg–Sn–Ca–Mn–xAl (x = 0,1.5 wt%) alloys with ultra-fine recrystallized grains were prepared by conventional extrusion(400 °C, 0.5 mm/s). Effects of aluminum (Al) on mechanical properties and microstructure of the Mg–1Sn–1Ca–0.5Mn(wt%) alloy were systematically investigated. By the addition of 1.5 wt% Al, the yield strength of the as-extruded alloysignificantly increased from 183 to 237 MPa. The as-cast alloys show a dendritic structure consists of α-Mg, (Mg, Al)2Ca,and CaMgSn phases. The as-extruded Mg–1Sn–1Ca–0.5Mn–1.5Al alloys exhibit a bimodal grain structure composed ofdynamic recrystallized (DRXed) fine grains and coarse unDRXed grains. Compared with Al free alloy, a lot of nano-scaleplanar Al2Caand rectangle shape Al8Mn5precipitated in the as-extruded alloy with 1.5 wt% Al. Meanwhile, the addition ofAl significantly strengthened alloys’ fiber texture with < 10–10 >//ED.

최적 금형연마 가공을 위한 센서 정보 통합 전문가 시스템 개발

안중환,김화영,申云峰,정해도,조규갑 韓國工作機械學會 2000 한국생산제조학회지 Vol.9 No.1

This paper presents a polishing expert system integrated with sensor information which can modify the polishing sequence and conditions initially determined by the system depending on the on-site polishing status. A practical system using AE sensor to detect the on-line polishing status is developed for the rotational polishing and the smoothly curved sur-face. Database and knowledge base for polishing processes are established by using the results of experiments and also expert's experience. Evaluations are performed for a die of headlight lamp by using both the sensor integrated expert sys-tem and the expert system without sensor. The test results show that the sensor integrated expert system provides more optimal polishing conditions since the proposed system takes advantage of the on-line sensor information.

Circular RNAs Regulate Cancer Onset and Progression via Wnt/β-Catenin Signaling Pathway

Yun-Feng Li,Jian Zhang,Lei Yu 연세대학교의과대학 2019 Yonsei medical journal Vol.60 No.12

Cancer remains to be a major challenge for public health providers, and is the second leading cause of death worldwide. Therefore,it is imperative to explore the mechanisms underlying cancer initiation and development, and design novel diagnostics andtherapeutics. Circular RNAs (circRNAs), which exhibit a covalently closed loop structure, are involved in a variety of diseases, includingcancer. The aberrant expression of circRNAs contributes to the initiation and development of various cancers by disruptingthe interplay of specific signaling pathways, including the Wnt/β-catenin pathway, which controls a plethora of cellular processesthat drive cancer development. The interactions between circRNAs (specifically expressed in different cancer tissues) andWnt/β-catenin signaling pathway presents potential diagnostic biomarkers and novel therapeutic targets. In this review, we havesummarized research discoveries on the functions of Wnt/β-catenin pathway-related circRNAs in the modulation of oncogenesisand progression of different types of cancer. We anticipate that our findings will contribute to the improvement or developmentof circRNAs-based strategies for cancer treatment.

Causes, Features, and Outcomes of Drug-Induced Liver Injury in 69 Children from China

( Yun Zhu ),( Yong Gang Li ),( Jia Bo Wang ),( Shu Hong Liu ),( Li Fu Wang ),( Yan Ling Zhao ),( Yun Feng Bai ),( Zhong Xia Wang ),( Jian Yu Li ),( Xiao He Xiao ) 대한소화기학회 2015 Gut and Liver Vol.9 No.4

Background/Aims: Drug-induced liver injury (DILI) is a frequent cause of pediatric liver disease; however, the data on DILI are remarkably limited. Methods: All 69 children hospitalized with DILI between January 2009 and December 2011 were retrospectively studied. Results: A total of 37.7% of the children had medical histories of respiratory infection. The clinical injury patterns were as follows: hepatocellular 89.9%, cholestatic 2.9%, and mixed 7.2%. Liver biopsies from 55 children most frequently demonstrated chronic (47.3%) and acute (27.3%) hepatitis. Hypersensitivity features, namely, fever (31.9%), rash (21.7%), and eosinophilia (1.4%), were found. Twenty-four children (34.8%) developed chronic DILI. Antibiotics (26.1%) were the most common Western medicines (WMs) causing DILI, and the major implicated herbs were Ephedra sinica and Polygonum multiflorum. Compared with WM, the children whose injuries were caused by Chinese herbal medicine (CHM) showed a higher level of total bilirubin (1.4 mg/dL vs 16.6 mg/dL, p=0.004) and a longer prothrombin time (11.8 seconds vs 17.3 seconds, p=0.012), but they exhibited less chronic DILI (2/15 vs 18/39, p=0.031). Conclusions: Most cases of DILI in children are caused by antibiotics or CHM used to treat respiratory infection and present with hepatocellular injury. Compared with WM, CHM is more likely to cause severe liver injury, but liver injury caused by CHM is curable. (Gut Liver 2015;9:525-533)

Characteristics of wind loading on internal surface and its effect on wind-induced responses of a super-large natural-draught cooling tower

Yun-feng Zou,Zheng-yi Fu,Xu-hui He,Hai-quan Jing,Ling-yao Li,Hua-wei Niu,Zheng-qing Chen 한국풍공학회 2019 Wind and Structures, An International Journal (WAS Vol.29 No.4

Wind loading is one of important loadings that should be considered in the design of large hyperbolic natural-draught cooling towers. Both external and internal surfaces of cooling tower are under the action of wind loading for cooling circulating water. In the previous studies, the wind loads on the external surface attracted concernedly attention, while the study on the internal surface was relatively ware. In the present study, the wind pressure on the internal surface of a 220 m high cooling tower is measured through wind tunnel testing, and the effect of ventilation rate of the packing layer on internal pressure is a major concern. The characteristics of internal wind pressure distribution and its effect on wind-induced responses calculated by finite element method are investigated. The results indicate that the wind loading on internal surface of the cooling tower behaves remarkable three-dimensional effect, and the pressure coefficient varies along both of height and circumferential directions. The non-uniformity is particularly strong during the construction stage. Analysis results of the effect of internal pressure on wind-induced responses show that the size and distribution characteristics of internal pressure will have some influence on wind-induced response, however, the outer pressure plays a dominant role in the wind-induced response of cooling tower, and the contribution of internal pressure to the response is small.

The research on the current situation of the mass fitness dance and the impact to the employment prospects of college students

Feng Ai Yun,Guo Jin Shi 한국무용연구학회 2011 한국무용연구학회 국제학술발표논문집 Vol.2011 No.-

This paper aims to explore the current situation of the mass fitness dance as well as the impacts, and analyse the employment prospects of mass fitness dance profession in China. Through the methods of literature review, interviews and other research methods, on the popular dance fitness status of the investigation, analysis of the advantage of the mass fitness dance in body-building exercise. In order to provide the theory basis for its development to open up a broader space.

Numerical simulations of interactions between solitary waves and elastic seawalls on rubble mound breakwaters

Yun-Feng Lou,Chuan Luo,Xian-Long Jin 국제구조공학회 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.53 No.3

Two dimensional numerical models and physical models have been developed to study the highly nonlinear interactions between waves and breakwaters, but several of these models consider the effects of the structural dynamic responses and the shape of the breakwater axis on the wave pressures. In this study, a multi-material Arbitrary Lagrangian Eulerian (ALE) method is developed to simulate the nonlinear interactions between nonlinear waves and elastic seawalls on a coastal rubble mound breakwater, and is validated experimentally. In the experiment, a solitary wave is generated and used with a physical breakwater model. The wave impact is validated computationally using a breakwater - flume coupling model that replicates the physical model. The computational results, including those for the wave pressure and the water-on-deck, are in good agreement with the experimental results. A local breakwater model is used to discuss the effects of the structural dynamic response and different design parameters of the breakwater on wave loads, together with pressure distribution up the seawall. A large-scale breakwater model is used to numerically study the large-scale wave impact problem and the horizontal distribution of the wave pressures on the seawalls.

A Generalized Hidden Markov Model and Its Applications in Recognition of Cutting States

Feng-Yun Xie,You-Min Hu,Bo Wu,Yan Wang 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.11

In the traditional hidden Markov model (HMM) for statistical learning and classification, aleatory uncertainty because of randomness and epistemic uncertainty that is due to the lack of knowledge are not differentiated. In this paper, a generalized hidden Markov model (GHMM) in the context of generalized interval probability theory is proposed. The parameters of GHMM are in the form of generalized interval probability, which provides a concise representation for the two kinds of uncertainty simultaneously. The generalized versions of the forward-backward, Viterbi, and Baum-Welch algorithms in GHMM are developed. The proposed algorithms take advantage of the algebraic property in the generalized interval probability. These algorithms provide an efficient approach to train the GHMM. The trained GHMM is used for state recognition with the criterion of maximum log-likelihood. A case study on recognizing the cutting states in manufacturing processes is provided to demonstrate the application of GHMM. The interval forms of the cutting signal are considered as the inputting of GHMM. The cutting states are recognized based on the learning algorithm of GHMM. With the two uncertainty components quantified, the reliability of GHMM in state recognition is superior to that of HMM.

키랄(S)-이부푸로펜 함유 고분자의 합성과 제조된 고분자의 분자 인식 메커니즘

Feng Yun Huang Fu,Bing Wang,Yan Sun 한국고분자학회 2013 폴리머 Vol.37 No.3

A group of molecularly imprinted polymers (MIPs) with specific recognition for chiral (S)-ibuprofen were successfully prepared based on hydrogen bonds, utilizing α-methacrylic acid as a functional monomer. The IR analysis of MIPs showed that the blue- and red-shifted hydrogen bonds were formed between templates and functional monomers in the process of self-assembly imprinting and re-recognition, respectively. According to UV-Vis analysis, we found that the ratio of host-guest complexes between template molecule and functional monomer was 1:1. The effect of crosslinker`s quantity on the polymerization was studied by transmission electron microscope (TEM). The adsorption selectivity experiments indicated that MIPs exhibited higher selectivity to (S)-ibuprofen than those to ketoprofen and (R)-ibuprofen, (S)-ibuprofen`s structural analogs.

대중 피트니스 댄스의 현황과 댄스 전공자의 취업 전망에 대한 영향 연구

Feng Ai Yun,Guo Jin Shi 한국무용연구학회 2011 한국무용연구학회 국제학술발표논문집 Vol.2011 No.-

본 논문의 목적은 대중 피트니스 댄스의 영향과 대중 피트니스 댄스의 현황을 연구하고, 중국에서 대중 피트니스 댄스 전공자의 취업 전망을 분석하는 것이다. 연구방법으로는 문헌연구와 전문가 인터뷰가 사용되고 그 외에도 다른 연구 방법론을 사용하여 대중적인 춤인 피트니스 댄스의 현황을 조사하고, 체력 단련 운동으로서의 대중 피트니스 댄스의 장점을 분석한다. 보다 포괄적인 범위에서 연구의 이론적 기초를 제공하기 위하여 대중 피트니스 댄스가 일반 대중들의 건강 증진에 얼마나 중요한 역할을 하고 있는지 입증하고자 한다.