Hot Deformation Characteristics and Processing Map Analysis of Pre-Forged AZ80 Magnesium Alloy

Shi‑quan Huang,Ming Lu,Sheng‑lan Luo,Hai‑lin He,You‑ping Yi 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.5

The hot deformation behavior of pre-forged AZ80 magnesium alloy is investigated by the isothermal compression tests attemperatures of 523–683 K and strain rates of 0.0001–0.1 s−1, and analyzed by the processing maps for guiding isothermaldie forging. Flow localization and even cracking occurs at low temperatures and high strain rates, where shear deformationdegree shows a positive correlation with the ��( ̇�� ) value. Two stability regions with high efficiency is found out by theprocessing maps. At common stability region with high temperatures and low strain rates, peak power dissipation efficiencydoes not represent optimum deformation condition as reported in other materials. A Z parameter criterion is introduced forparameters optimization. javascript:void(0); a new stability domain of 523–590 K and 0.0001–0.01 s−1 is observed, which istypical for fine microstructure composed of equiaxed clean α-Mg grains and big particles both about 1 μm (573 K/0.01 s−1).Super plasticity is speculated to occur at that condition.

The modal characteristics of non-uniform multi-span continuous beam bridges

Lu-ning Shi,Wei-ming Yan,Hao-xiang He 국제구조공학회 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.52 No.5

According to the structure characteristics of the non-uniform beam bridge, a practical model for calculating the vibration equation of the non-uniform beam bridge is given and the application scope of the model includes not only the beam bridge structure but also the non-uniform beam with added masses andelastic supports. Based on the Bernoulli-Euler beam theory, extending the application of the modal perturbation method and establishment of a semi-analytical method for solving the vibration equation of thenon-uniform beam with added masses and elastic supports based is able to be made. In the modal subspace of the uniform beam with the elastic supports, the variable coefficient differential equation that describes the dynamic behavior of the non-uniform beam is converted to nonlinear algebraic equations. Extending the application of the modal perturbation method is suitable for solving the vibration equation of the simply supported and continuous non-uniform beam with its arbitrary added masses and elastic supports. The examples, that are analyzed, demonstrate the high precision and fast convergence speed of the method. Further study of the timesaving method for the dynamic characteristics of symmetrical beam and the symmetry of mode shape should be developed. Eventually, the effects of elastic supports and added masseson dynamic characteristics of the three-span non-uniform beam bridge are reported.

Database and Tools for Metabolic Network Analysis

Lu Shi Jing,Farah Fathiah Muzaffar Shah,Mohd Saberi Mohamad,Nur Laily Hamran,Abdul Hakim Mohamed Salleh,Safaai Deris,Hany Alashwal 한국생물공학회 2014 Biotechnology and Bioprocess Engineering Vol.19 No.4

Metabolic network analysis has attracted muchattention in the area of systems biology. It has a profoundrole in understanding the key features of organismmetabolic networks and has been successfully applied inseveral fields of systems biology, including in silico geneknockouts, production yield improvement using engineeredmicrobial strains, drug target identification, and phenotypeprediction. A variety of metabolic network databases andtools have been developed in order to assist research inthese fields. Databases that comprise biochemical data arenormally integrated with the use of metabolic networkanalysis tools in order to give a more comprehensive result. This paper reviews and compares eight databases as wellas twenty one recent tools. The aim of this review is tostudy the different types of tools in terms of the featuresand usability, as well as the databases in terms of the scopeand data provided. These tools can be categorised intothree main types: standalone tools; toolbox-based tools;and web-based tools. Furthermore, comparisons of thedatabases as well as the tools are also provided to helpsoftware developers and users gain a clearer insight and abetter understanding of metabolic network analysis. Additionally, this review also helps to provide usefulinformation that can be used as guidance in choosing toolsand databases for a particular research interest.

A Research of Engineering Construction Based on Credit Risk

Lu Shi-bao,Huang Qiang,ZHANG Yong-yong,SUN Dong-yong 인하대학교 정석물류통상연구원 2009 인하대학교 정석물류통상연구원 학술대회 Vol.2009 No.10

Engineering construction companies often default on the contract expird, which makes the enterprise"s own quality and credibility be affected. Therefore, the construction enterprises should be aware that the value of their own credit, financial sector should also be on the borrowers to assess credit risk, so as not to appear in the portfolio risk. This article utilizes the modern credit grading method toevaluate the construction enterprise"s Credit rating. The study found: Change index credit transpose matrix has a great impact. It will affect the credit rating chages. Credit Change this index ranged from zero when the critical state has a different default status, when the credit quality index greater than zero, the rise in the value of its credit; if the credit quality index is less than zero, the credit quality of the index on the lower Level; If zero, credit rating is tomaintain the normal status, and obtained the illustration through the example.

The modal characteristics of non-uniform multi-span continuous beam bridges

Shi, Lu-Ning,Yan, Wei-Ming,He, Hao-Xiang Techno-Press 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.52 No.5

According to the structure characteristics of the non-uniform beam bridge, a practical model for calculating the vibration equation of the non-uniform beam bridge is given and the application scope of the model includes not only the beam bridge structure but also the non-uniform beam with added masses and elastic supports. Based on the Bernoulli-Euler beam theory, extending the application of the modal perturbation method and establishment of a semi-analytical method for solving the vibration equation of the non-uniform beam with added masses and elastic supports based is able to be made. In the modal subspace of the uniform beam with the elastic supports, the variable coefficient differential equation that describes the dynamic behavior of the non-uniform beam is converted to nonlinear algebraic equations. Extending the application of the modal perturbation method is suitable for solving the vibration equation of the simply supported and continuous non-uniform beam with its arbitrary added masses and elastic supports. The examples, that are analyzed, demonstrate the high precision and fast convergence speed of the method. Further study of the timesaving method for the dynamic characteristics of symmetrical beam and the symmetry of mode shape should be developed. Eventually, the effects of elastic supports and added masses on dynamic characteristics of the three-span non-uniform beam bridge are reported.

Research on Building of a Professional Learning Community for China’s Urban and Rural Primary & Secondary School Teachers - Take Hefei City in Anhui Province as an Example -

Shi xiu Lu,Moon bo Sim 한국지역복지정책연구회 2016 지역복지정책 Vol.27 No.-

사회적 공평과 공정은 국가의 건강성과 수준을 평가하는 중요한 기준이 되며, 국민의 권리이자 존엄성을 보장하는 척도다. 교육에서의 공평성은 공평한 사회를 이루기 위한 기초이자 방법이기도 하다. 중국은30여 년의 개혁개방을 통해 종합적 국력이 거대하게 향상되었고, 사회경제가 빠르게 발전된 반면 그 빈부격차도 갈수록 커지고 있다. 이러한 경제적 불평등은 교육에도 반영되고 있다. 도시와 농촌 간, 지역 간, 계층 간에 존재하는 교육적 자원 및 기회 등의 불균형 현상은 이미 사회적 공평성을 해치고 사회적 조화에 악영향이 끼치고 있다. 특히 도시와 농촌간의 불균형은 날로 심해져 교사 부족 현상으로 나타나고 있다. 이러한 문제점을 해결하기 위해서 중국 정부는 농촌 학교 교사 육성과 교육 재배치 등 여러 정책을 잇따라 발표해 왔고 많은 조치를 실행해 왔다. 예컨대, ‘특설직장’계획, 도농(都農) 교사교류 제도, 도농 교육공동체 설립, 교사지원계획 등등. 본 논문은 중국 안휘성 합비시의 도농학교 교사학습공동체설립 상황과 그 문제점을 파악하여, 향후 교사전공 학습공동체 설립에 참고자료로 제공하고자 함이 그 연구 목적이다. 연구에는 교육공평이론, 학습형 조직이론과 교육생태학 이론을 운용하였으며, 설문조사와 인터뷰 그리고 문헌분석 방법으로 안휘성 합비시의 도농학교 교육공동체 안의 교사학습공동체를 조사하여, 다섯 가지 구체적 문제점을 제시하였다. 첫째, 교사전공학습공동체의 주체가 단편적이다. 둘째, 교사 교류의 실효성이 낮다. 셋째, 교사학습공동체 구성원간의 협력의지가 부족하다. 넷째, 교사전공학습공동체의 현대 정보화 기술 운용이 미흡하며, 이른바 교사학습공동체가 널리 설립되어 있지 않다. 다섯째, 학교가 교사전공학습공동체에 제공하는 경비 및 제도적 지원이 제한적이다. 이러한 문제점에 대한 개선책으로 첫째, 교사학습공동체 설립의 주체를 다원화하고 교사학습공동체의 참여도를 향상시켜야 한다. 둘째, 교사교류시스템을 효율화해야 한다. 셋째, 협력공생이라는 교사 협력 문화를 제고하고 팀학습 의식과 능력을 향상시켜야 한다. 넷째, 인터넷 및 현대 정보화기술을 충분히 활용하고 교사학습공동체의 조직을 다양화해야 한다. 다섯째, 교사전공학습공동체에 대한 각 방면의 지원을 증대시켜야 한다.

Reliable H<SUB>∞</SUB> Controller Design for a Class of Uncertain Linear Systems with Actuator Failures

Shi-Lu Dai,Jun Zhao 대한전기학회 2008 International Journal of Control, Automation, and Vol.6 No.6

This paper is concerned with the reliable H∞ controller design problem for uncertain linear systems against actuator failures. In the design, the H∞ performance of the closed-loop system is optimized during normal operation (without failures) while the system satisfies a prescribed H∞ performance level in the case of actuator failures. Single and parameter-dependent Lyapunov function approaches are applied in designing suboptimal reliable H∞ controllers. Simulation studies are presented to demonstrate the effectiveness of the proposed design procedures.

Function and Molecular Ecology Significance of Two Catechol-Degrading Gene Clusters in Pseudomonas putida ND6

( Sanyuan Shi ),( Liu Yang ),( Chen Yang ),( Shanshan Li ),( Hong Zhao ),( Lu Ren ),( Xiaokang Wang ),( Fuping Lu ),( Ying Li ),( Huabing Zhao ) 한국미생물생명공학회(구 한국산업미생물학회) 2021 Journal of microbiology and biotechnology Vol.31 No.2

Many bacteria metabolize aromatic compounds via catechol as a catabolic intermediate, and possess multiple genes or clusters encoding catechol-cleavage enzymes. The presence of multiple isozyme-encoding genes is a widespread phenomenon that seems to give the carrying strains a selective advantage in the natural environment over those with only a single copy. In the naphthalene-degrading strain Pseudomonas putida ND6, catechol can be converted into intermediates of the tricarboxylic acid cycle via either the ortho- or meta-cleavage pathways. In this study, we demonstrated that the catechol ortho-cleavage pathway genes (catB_IC_IA_I and catB_IIC_IIA_II) on the chromosome play an important role. The cat_I and cat_II operons are co-transcribed, whereas catA_I and catA_II are under independent transcriptional regulation. We examined the binding of regulatory proteins to promoters. In the presence of cis-cis-muconate, a well-studied inducer of the cat gene cluster, CatR_I and CatR_II occupy an additional downstream site, designated as the activation binding site. Notably, CatR_I binds to both the cat_I and cat_II promoters with high affinity, while CatR_II binds weakly. This is likely caused by a T to G mutation in the G/T-N11-A motif. Specifically, we found that CatR_I and CatR_II regulate catB_IC_IA_I and catB_IIC_IIA_II in a cooperative manner, which provides new insights into naphthalene degradation.

Intravenous Tenecteplase for Acute Ischemic Stroke Within 4.5–24 Hours of Onset (ROSE-TNK): A Phase 2, Randomized, Multicenter Study

Wang Lu,Dai Ying-Jie,Cui Yu,Zhang Hong,Jiang Chang-Hao,Duan Ying-Jie,Zhao Yong,Feng Ye-Fang,Geng Shi-Mei,Zhang Zai-Hui,Lu Jiang,Zhang Ping,Zhao Li-Wei,Zhao Hang,Ma Yu-Tong,Song Cheng-Guang,Zhang Yi,Ch 대한뇌졸중학회 2023 Journal of stroke Vol.25 No.3

Background and Purpose Intravenous tenecteplase (TNK) efficacy has not been well demonstrated in acute ischemic stroke (AIS) beyond 4.5 hours after onset. This study aimed to determine the effect of intravenous TNK for AIS within 4.5 to 24 hours of onset. Methods In this pilot trial, eligible AIS patients with diffusion-weighted imaging (DWI)-fluid attenuated inversion recovery (FLAIR) mismatch were randomly allocated to intravenous TNK (0.25 mg/kg) or standard care within 4.5–24 hours of onset. The primary endpoint was excellent functional outcome at 90 days (modified Rankin Scale [mRS] score of 0–1). The primary safety endpoint was symptomatic intracranial hemorrhage (sICH). Results Of the randomly assigned 80 patients, the primary endpoint occurred in 52.5% (21/40) of TNK group and 50.0% (20/40) of control group, with no significant difference (unadjusted odds ratio, 1.11; 95% confidence interval 0.46–2.66; <i>P</i>=0.82). More early neurological improvement occurred in TNK group than in control group (11 vs. 3, <i>P</i>=0.03), but no significant differences were found in other secondary endpoints, such as mRS 0–2 at 90 days, shift analysis of mRS at 90 days, and change in National Institutes of Health Stroke Scale score at 24 hours and 7 days. There were no cases of sICH in this trial; however, asymptomatic intracranial hemorrhage occurred in 3 of the 40 patients (7.5%) in the TNK group. Conclusion This phase 2, randomized, multicenter study suggests that intravenous TNK within 4.5–24 hours of onset may be safe and feasible in AIS patients with a DWI-FLAIR mismatch.

Effect of Tea on Resistance to Type 2 Diabetes

Peng Lu,Kai Fan,Ya-Ting Lu,Yuan-Xu Shi,Dong-Mei Fan,Xiao-Chang Wang 한국차학회 2015 한국차학회지 Vol.- No.S

Insulinotropic hormone glucagon-like peptide-1 (GLP-1) degrades rapidly under the catalytic of dipeptidyl peptidase IV (DPP-IV). Consequently, DPP-IV which is widely expressed in small intestine takes a key role in the prevention and treatment of Type 2 Diabetes. To identify the capability of anti-type 2 diabetes by tea, the inhibition of different types of Chinese teas on DPP-IV was tested. The inhibitory ratio of Buddha Longjing is 31.74%, Tangji Gaoshan Tea is 62.08% (p < 0.01), Yunnan black tea is 66.29% (p < 0.01), Lapsang souchon is 76.40% (p <0.01), Dahongpao is 62.08% (p < 0.01), Tieguanyin is 66.85% (p < 0.01), Moganhuangya is 65.45% (p < 0.01),Huoshanhuangya is 50.56% (p < 0.05).