INDUCTION OF APOPTOSIS BY GINSENG SAPONIN METABOLITE IN U937 HUMAN MONOCYTIC LEUKEMIA CELLS

We report the cytotoxicity of the ginseng saponin metabolite, Compound K (20‐O‐D‐glucopyranosyl‐20(S)‐protopanaxadiol, IH901) on various human leukemia cell lines. Compound K had the most effect on U937, a human monocytic leukemia cell line among the tested cell lines. Compound K‐treated U937 cells showed characteristics of apoptosis: an exposure of phosphatidylserine from the inner cell membrane to the outer cell membrane, the formation of apoptotic bodies and DNA fragmentation. Compound K induced apoptosis by up‐regulating Bax, disrupting the mitochondrial membrane potential, and by activating caspase 9 and caspase 3. Therefore, we suggest that Compound K inhibits U937 cell growth by inducing apoptosis through the up‐regulation of Bax and caspase activation.     

Surface Modelling and Mesh Generation for Simulating Superplastic Forming

This paper presents an approach which enables surface modelling, mesh generation and the Finite Element (FE) analysis to be integrated together to simulate superplastic forming process for complex shaped components. Techniques have been developed to generate an FE mesh over non-four-sided surface areas, the boundaries of which are Bezier curves of arbitrary degree, using a consistent expression. Theoretical evidence is given to determine the number of Bezier triangular patches required for accurately re-constructing die surfaces within a commercial FE solver. The developed techniques have been successfully used in determining the process parameters for forming a 3D rectangular box.     

A COUPLED MORPHODYNAMIC MODEL FOR APPLICATIONS INVOLVING WETTING AND DRYING

This work presents a new finite volume Godunov-type model for predicting morphological changes under the rapidly varying flood conditions with wetting and drying.The model solves the coupled shallow water and Exner equations,with the interface fluxes evaluated by an Harten-Lax-van Leer-Contact(HLLC) approximate Riemann solver.Well-balanced solution is achieved using the surface gradient method and wetting and drying are handled by a non-negative reconstruction approach.The new model is validated against several theoretical benchmark tests and promising results are obtained.     

INFLUENCE OF AGING ON MICROSTRUCTURE AND TENSILE BEHAVIOR OF Al ALLOY 8090

The vuriations of microstructure and tensile behavior of an Al—Li一Cu—Mg—Zr alloy during aging are studied in this paper.It has been found that the fine δ’—phase precipitated inthe underaging condition and that theδ’—,S—and T_1—phases precipitate in the peak agingand the overaging conditions.The alloy exhibits tuansgranular fracture on the underagingcondition and mixture of transgranular and intergranular ruptures in the peak the peak aging andoveraging conditions.     

Microstructure Evolution of a 10Cr Heat-Resistant Steel during High Temperature Creep

The microstructure evolution of a 10Cr ferritic/martensitic heat-resistant steel during creep at 600℃ was investigated in this work.Creep tests demonstrated that the 10Cr steel had higher creep strength than conventional ASME-P92 steel at 600℃.The microstructure after creep was studied by transmission electron microscopy,scanning electron microscopy and electron probe microanalysis.It was revealed that the martensitic laths were coarsened with time and eventually developed into subgrains after 8354 h.Laves phase was observed to grow and cluster along the prior austenite grain boundaries during creep and caused the fluctuation of solution and precipitation strengthening effects,which was responsible for the two slope changes on the creep rupture strength vs rupture time curve.It was also revealed that the microstructure evolution could be accelerated by stress,which resulted in the lower hardness in the deformed part of the creep specimen,compared with the aging part.     

基于广义哈密顿系统理论的汽轮调速器分散无源控制

提出了一种预置功角反馈的方法，推导出多机系统汽轮机调速系统的广义受控哈密顿系统模型，进而在哈密顿结构的基础上进行无源化控制器的设计。控制策略的所有变量都是本地可量测的，只与本机组的状态量有关，与其他机组的状态量和输电网络的参数无关，因而具有分散性。4机系统仿真结果表明，该控制规律可以提高电力系统的暂态稳定性和动态性能。     

Turbopump Condition Monitoring Using Incremental Clustering and One-class Support Vector Machine

Turbopump condition monitoring is a significant approach to ensure the safety of liquid rocket engine (LRE).Because of lack of fault samples,a monitoring system cannot be trained on all possible condition patterns.Thus it is important to differentiate abnormal or unknown patterns from normal pattern with novelty detection methods.One-class support vector machine (OCSVM) that has been commonly used for novelty detection cannot deal well with large scale samples.In order to model the normal pattern of the turbopump with OCSVM and so as to monitor the condition of the turbopump,a monitoring method that integrates OCSVM with incremental clustering is presented.In this method,the incremental clustering is used for sample reduction by extracting representative vectors from a large training set.The representative vectors are supposed to distribute uniformly in the object region and fulfill the region.And training OCSVM on these representative vectors yields a novelty detector.By applying this method to the analysis of the turbopump’s historical test data,it shows that the incremental clustering algorithm can extract 91 representative points from more than 36 000 training vectors,and the OCSVM detector trained on these 91 representative points can recognize spikes in vibration signals caused by different abnormal events such as vane shedding,rub-impact and sensor faults.This monitoring method does not need fault samples during training as classical recognition methods.The method resolves the learning problem of large samples and is an alternative method for condition monitoring of the LRE turbopump.     

探索基于自然的解决方案中景观设计的角色变化——对20年专业实践的反思

基于自然的解决方案（NbS）是与自然栖息地相互促进的解决方案,利用健康的自然及人工生态系统的功能,封存碳并支持生物多样性恢复。通过对致力于与自然合作的职业生涯的反思,探讨了景观规划和设计方法的演变历程,从单一目标的解决方案到系统性思维及整体设计,从经验性/定性的决策到量化的解决方案。分3个阶段展开实践探讨：1）绿化灰色基础设施;2）将自然景观融入公共空间;3）自然向好的未来。探索如何将NbS理念传输给政策制定者并充分融入广大公众的社会意识与日常认知领域,继而促成更广泛、更长期的国际环境上的成功。