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Kinematic error separation on five-axis NC machine tool based on telescoping double ball bar

Min WANG, Jianzhong HU, Tao ZAN

《机械工程前沿（英文）》 2010年 第5卷 第4期   页码 431-437 doi: 10.1007/s11465-010-0110-1

摘要： The theory and algorithm of the homogeneous transformation matrix (HTM) method are applied in establishing the kinematic error model of five-axis machining tool with two-axis turntable. Based on this model, a new method for the kinematic error separation in five-axis numerical control (NC) machining tool is proposed. In this study, three types of simultaneous three-axis control motions are designed for each rotary axis to identify the deviations. In the measurement, two translational axes and one rotary axis are simultaneously controlled to keep a constant distance between the tool and the worktable. Telescoping double ball bar is used to measure the relative distance between the spindle and the worktable in the motion of NC machining tool. Finally, the value measured by telescoping double ball bar is substituted into the model to obtain kinematic error of NC machining tool. Comparison has confirmed that the proposed method is high precision and can be applied to effectively and conveniently measure the five-axis machining tool.

关键词： error modeling     error separation     telescoping double ball bar     five-axis numerical control (NC) machining tool    

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Determination of the feasible setup parameters of a workpiece to maximize the utilization of a five-axis

Aqeel AHMED, Muhammad WASIF, Anis FATIMA, Liming WANG, Syed Amir IQBAL

《机械工程前沿（英文）》 2021年 第16卷 第2期   页码 298-314 doi: 10.1007/s11465-020-0621-3

摘要： The machining industry must maximize the machine tool utilization for its efficient and effective usage. Determining a feasible workpiece location is one of the significant tasks performed in an iterative way via machining simulations. The maximum utilization of five-axis machine tools depends upon the cutting system’s geometry, the configuration of the machine tool, and the workpiece’s location. In this research, a mathematical model has been developed to determine the workpiece’s feasible location in the five-axis machine tool for avoiding the number of iterations, which are usually performed to eliminate the global collision and axis limit errors. In this research, a generic arrangement of the five-axis machine tool has been selected. The mathematical model of post-processor has been developed by using kinematic modeling methods. The machine tool envelopes have been determined using the post-processor and axial limit. The tooltip reachable workspace is determined by incorporating the post-processor, optimal cutting system length, and machining envelope, thereby further developing an algorithm to determine the feasible workpiece setup parameters accurately. The algorithm’s application has been demonstrated using an example. Finally, the algorithm is validated for feasible workpiece setup parameters in a virtual environment. This research is highly applicable in the industry to eliminate the number of iterations performed for the suitable workpiece setup parameters.

关键词： workpiece setup parameter     five-axis     space utilization     setup parameters     machine tool    

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Five-axis rough machining for impellers

Ruolong QI, Weijun LIU, Hongyou BIAN, Lun LI

《机械工程前沿（英文）》 2009年 第4卷 第1期   页码 71-76 doi: 10.1007/s11465-009-0010-4

摘要： The most important components used in aerospace, ships, and automobiles are designed with free form surfaces. An impeller is one of the most important components that is difficult to machine because of its twisted blades. Rough machining is recognized as the most crucial procedure influencing machining efficiency and is critical for the finishing process. An integrated rough machining course with detailed algorithms is presented in this paper. An algorithm for determining the minimum distance between two surfaces is applied to estimate the tool size. The space between two blades that will be cleared from the roughcast is divided to generate CC points. The tool axis vector is confirmed based on flank milling using a simple method that could eliminate global interference between the tool and the blades. The result proves that the machining methodology presented in this paper is useful and successful.

关键词： five-axis     impeller     tool-path     planning     flank milling     ruled surface    

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Optimization model for rotor blades of horizontal axis wind turbines

LIU Xiong, CHEN Yan, YE Zhiquan

《机械工程前沿（英文）》 2007年 第2卷 第4期   页码 483-488 doi: 10.1007/s11465-007-0084-9

摘要： This paper presents an optimization model for rotor blades of horizontal axis wind turbines. The model refers to the wind speed distribution function on the specific wind site, with an objective to satisfy the maximum annual energy output. To speed up the search process and guarantee a global optimal result, the extended compact genetic algorithm (ECGA) is used to carry out the search process. Compared with the simple genetic algorithm, ECGA runs much faster and can get more accurate results with a much smaller population size and fewer function evaluations. Using the developed optimization program, blades of a 1.3 MW stall-regulated wind turbine are designed. Compared with the existing blades, the designed blades have obviously better aerodynamic performance.

关键词： population     extended     algorithm     developed optimization     accurate    

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中医五脏相关学说研究——从五行到五脏相关

邓铁涛,郑洪

《中国工程科学》 2008年 第10卷 第2期   页码 7-13

摘要：

五行学说对中医学有深刻的影响，体现了传统医学重视联系、整体的特点，但五行学说本身有局限性，不能全面地反映事物间的普遍联系。中医以五脏配属五行，吸收了五行学说的精华；又根据脏腑学说的理论，在实践中超越了五行的限制。因此，中医的理论可名为“五脏相关学说”。在中医理论现代化中，可以将五脏之间的影响归纳为促进、抑制和协同3种关系，从多种角度来阐明中医的整体性与联系观。

关键词： 中医     脏腑学说     五行    

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多孔质气体静压轴承在三轴转台设计中的应用

杜金名

《中国工程科学》 2005年 第7卷 第1期   页码 65-68

摘要：

气体静压轴承广泛应用于航空、航天、精密电子工业中。三轴转台是高精度的测试设备，用来对惯性系统和惯性元件进行检定、标定以及建立相应的误差模型，它的测试精度直接影响航空、航天等飞行器的控制和导航。转台的检测精度与回转轴的回转精度有密切关系。多孔质气体静压轴承同其他节流形式的轴承相比具有很高的承载能力、静态刚度以及很好的阻尼效应。文章对多孔质气体静压轴承进行了理论分析，并同气体静压小孔节流轴承的静态性能进行了比较，结果表明，此类轴承的承载能力明显优于小孔节流轴承。

关键词： 气体静压轴承     多孔质     小孔节流     三轴转台    

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Performance of vertical axis water turbine with eye-shaped baffle for pico hydropower

Zhuohuan HU, Dongcheng WANG, Wei LU, Jian CHEN, Yuwen ZHANG

《能源前沿（英文）》 2022年 第16卷 第4期   页码 683-696 doi: 10.1007/s11708-020-0689-9

摘要： A series of inline pico hydropower systems, which could be used in confined space, especially for water distribution networks (WDNs), was designed and investigated. The turbine with an eye-shaped vertical water baffle was developed to evaluate the hydraulic performance. A three-dimensional dynamic mesh was employed and the inlet velocity was considered as the inlet boundary condition, whereas the outlet boundary was set as the outflow. Then, numerical simulations were conducted and the standard turbulence model was found to be the best capable of predicting flow features through the comparison with the experimental results. The effects of the opening diameter of the water baffle and installation angle of the rotor on the flow field in the turbine were investigated. The results suggested that the water baffle opening at = 30 mm and the rotor at a 52° angle could achieve the highest efficiency of 5.93%. The proper eye-shaped baffle not only accelerates the fluid flow and generates positive hydrodynamic torque, but also eliminates the flow separation. The scheme proposed in this paper can be exploited for practical applications in the water pipelines at various conditions and power requirements.

关键词： vertical axis water turbine     eye-shaped     vertical water baffle     pico hydropower    

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Role of the forkhead transcription factor FOXO-FOXM1 axis in cancer and drug resistance

null

《医学前沿（英文）》 2012年 第6卷 第4期   页码 376-380 doi: 10.1007/s11684-012-0228-0

摘要：

The forkhead transcription factors FOXO and FOXM1 have pivotal roles in tumorigenesis and in mediating chemotherapy sensitivity and resistance. Recent research shows that the forkhead transcription factor FOXM1 is a direct transcriptional target repressed by the forkhead protein FOXO3a, a vital downstream effector of the PI3K-AKT-FOXO signaling pathway. Intriguingly, FOXM1 and FOXO3a also compete for binding to the same gene targets, which have a role in chemotherapeutic drug action and sensitivity. An understanding of the role and regulation of the FOXO-FOXM1 axis will impact directly on our knowledge of chemotherapeutic drug action and resistance in patients, and provide new insights into the design of novel therapeutic strategy and reliable biomarkers for prediction of drug sensitivity.

关键词： FOXO3a     FOXM1     transcription factor     cancer     drug resistance     tumorigenesis    

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Estimation of power in low velocity vertical axis wind turbine

Sampath S. S.,Sawan SHETTY,Chithirai Pon Selvan M.

《机械工程前沿（英文）》 2015年 第10卷 第2期   页码 211-218 doi: 10.1007/s11465-015-0338-x

摘要：

The present work involves in the construction of a vertical axis wind turbine and the determination of power. Various different types of turbine blades are considered and the optimum blade is selected. Mechanical components of the entire setup are built to obtain maximum rotation per minute. The mechanical energy is converted into the electrical energy by coupling coaxially between the shaft and the generator. This setup produces sufficient power for consumption of household purposes which is economic and easily available.

关键词： wind turbine     shaft design     power generation     generator    

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FMO3--TMAO axis modulates the clinical outcome in chronic heart-failure patients with reduced ejection

《医学前沿（英文）》 2022年 第16卷 第2期   页码 295-305 doi: 10.1007/s11684-021-0857-2

摘要： The association among plasma trimethylamine-N-oxide (TMAO), FMO3 polymorphisms, and chronic heart failure (CHF) remains to be elucidated. TMAO is a microbiota-dependent metabolite from dietary choline and carnitine. A prospective study was performed including 955 consecutively diagnosed CHF patients with reduced ejection fraction, with the longest follow-up of 7 years. The concentrations of plasma TMAO and its precursors, namely, choline and carnitine, were determined by liquid chromatography-mass spectrometry, and the FMO3 E158K polymorphisms (rs2266782) were genotyped. The top tertile of plasma TMAO was associated with a significant increment in hazard ratio (HR) for the composite outcome of cardiovascular death or heart transplantation (HR=1.47, 95% CI=1.13–1.91, P=0.004) compared with the lowest tertile. After adjustments of the potential confounders, higher TMAO could still be used to predict the risk of the primary endpoint (adjusted HR=1.33, 95% CI=1.01–1.74, P=0.039). This result was also obtained after further adjustment for carnitine (adjusted HR=1.33, 95% CI=1.01–1.74, P=0.039). The FMO3 rs2266782 polymorphism was associated with the plasma TMAO concentrations in our cohort, and lower TMAO levels were found in the AA-genotype. Thus, higher plasma TMAO levels indicated increased risk of the composite outcome of cardiovascular death or heart transplantation independent of potential confounders, and the FMO3 AA-genotype in rs2266782 was related to lower plasma TMAO levels.

关键词： chronic heart failure     trimethylamine-N-oxide     flavin monooxygenase 3     single nucleotide polymorphism    

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Chidamide inhibits the NOTCH1-MYC signaling axis in T-cell acute lymphoblastic leukemia

《医学前沿（英文）》 2022年 第16卷 第3期   页码 442-458 doi: 10.1007/s11684-021-0877-y

摘要： T-cell acute lymphoblastic leukemia (T-ALL) is one of the most dangerous hematological malignancies, with high tumor heterogeneity and poor prognosis. More than 60% of T-ALL patients carry NOTCH1 gene mutations, leading to abnormal expression of downstream target genes and aberrant activation of various signaling pathways. We found that chidamide, an HDAC inhibitor, exerts an antitumor effect on T-ALL cell lines and primary cells including an anti-NOTCH1 activity. In particular, chidamide inhibits the NOTCH1-MYC signaling axis by down-regulating the level of the intracellular form of NOTCH1 (NICD1) as well as MYC, partly through their ubiquitination and degradation by the proteasome pathway. We also report here the preliminary results of our clinical trial supporting that a treatment by chidamide reduces minimal residual disease (MRD) in patients and is well tolerated. Our results highlight the effectiveness and safety of chidamide in the treatment of T-ALL patients, including those with NOTCH1 mutations and open the way to a new therapeutic strategy for these patients.

关键词： T-cell acute lymphoblastic leukemia     HDAC inhibitor     chidamide     NOTCH1     MYC     ubiquitination    

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Effects of parenteral nutrition with and without GH on the GH/IGF-1 axis after hepatectomy in hepatocellular

CAO Jie, LUO Shimin, LIANG Lijian, LAI Jiaming, CHEN Shanming

《医学前沿（英文）》 2007年 第1卷 第3期   页码 287-293 doi: 10.1007/s11684-007-0055-x

摘要： Postoperative hepatic insulin-like growth factor-1 (IGF-1) production may be severely disturbed in patients with liver cirrhosis. Complex alterations in the GH/IGF-1 axis are thought to play an important role in the protein catabolism that complicates major surgical procedures. The aim of this study was to explore the effects of parenteral nutrition (PN) with and without growth hormone (GH) on the GH/IGF-1 axis after hepatectomy for hepatocellular carcinoma (HCC) with cirrhosis and evaluate the potential roles of recombinant human GH (rhGH) therapy. Twenty-four patients with HCC with cirrhosis who underwent hepatectomy were randomly divided into two groups: a PN group ( = 12) and an rhGH+PN group ( = 12). Liver function, serum GH, IGF-1 and IGFBP-3 were measured before the operation and at postoperative days (POD) 1 and 6. Insulin-like growth factor-1 and IGFBP-3 mRNA in the liver tissue was detected by RT-PCR. The liver Ki67 immunohistochemistry staining was studied. At the same time, 12 patients with cholelithiasis or liver hemangioma who underwent operation served as normal control group. On POD 6, serum prealbumin, GH, IGF-1, IGFBP-3, hepatic IGF-1 mRNA, IGFBP-3 mRNA and liver Ki67 LI were higher in the rhGH+PN group than in the PN group. There was no significant difference in the 6- and 12-month tumor-free survival rate and the median tumor-free survival time between the PN group and the rhGH+PN group (〉0.05). These data indicate that rhGH+PN could ameliorate the changes in the GH/IGF-1 axis after hepatectomy for HCC in the setting of cirrhosis.

关键词： control     function     production     surgical     Complex    

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IN VITRO ACTIVITY OF EXTRACTS OF FIVE MEDICINAL PLANT SPECIES ON PLANT PATHOGENIC FUNGI

《农业科学与工程前沿（英文）》 2021年 第8卷 第4期   页码 635-644 doi: 10.15302/J-FASE -2020343

摘要：

The antifungal effectiveness of extracts of five medicinal plant species was determined. The inhibitory activity of extracts of Eucalyptus tereticornis, Xanthium sibiricum, Artemisia argyi, Tupistra chinensis and Pyrola calliantha were evaluated against the mycelial growth of the plant pathogenic fungi Aspergillus niger, Botrytis cinerea, Penicillium digitatum, P. expansum, P. italicumand Rhizopus stolonifer. All plant extracts were prepared at 60°C using solvents (either water, 50% ethanol (v/v), 95% ethanol (v/v), ethyl acetate or petroleum ether). Fungicidal effects of all plants tested were confirmed. Different extracts from the same plant species gave different degrees of inhibition. All aqueous extracts had weak or no activity on all fungi tested. Ethyl acetate and 95% ethanol extracts from T. chinensis rhizomes gave greater inhibition and a broader spectrum inhibition than the other extracts. T. chinensis may have potential as a new natural fungicide and may be used for the preservation of agricultural and forestry products such as fruits and vegetables.

 

关键词： Botrytis cinerea / food preservation / plant diseases / plant pathogenic fungi / Tupistra chinensis    

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Quality and efficiency improvement technology for five megawatt offshore wind turbines and its application

Huali HAN

《工程管理前沿（英文）》 2020年 第7卷 第4期   页码 618-621 doi: 10.1007/s42524-020-0142-0

关键词： renewable energy     megawatt offshore wind turbine     technology-driven     quality improvement    

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硅微z轴谐振陀螺仪负电刚度效应分析及实验验证

夏敦柱,周百令,王寿荣

《中国工程科学》 2007年 第9卷 第8期   页码 66-68

摘要：

介绍了在开环工作状态下硅微z轴谐振陀螺仪由于加工工艺缺陷所导致的误差机理。为减小陀螺仪初始电容差和抑制正交耦合误差，提出了一种闭环控制检测策略。重点分析了其力矩反馈器的电刚度效应并给出其线性数学模型表示式。通过对硅微z轴陀螺仪敏感模态的反馈力与谐振频率的关系分析，间接得出了在敏感方向上电负刚度与力矩器所施电压的内在联系，并在实验上进一步验证电刚度效应。这将为下一步闭环控制方案的设计奠定重要基础。

关键词： 硅微z轴陀螺仪     负电刚度     力矩反馈器     微机电系统    

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标题 作者 时间 类型 操作

Kinematic error separation on five-axis NC machine tool based on telescoping double ball bar

Min WANG, Jianzhong HU, Tao ZAN

期刊论文

Determination of the feasible setup parameters of a workpiece to maximize the utilization of a five-axis

Aqeel AHMED, Muhammad WASIF, Anis FATIMA, Liming WANG, Syed Amir IQBAL

期刊论文

Five-axis rough machining for impellers

Ruolong QI, Weijun LIU, Hongyou BIAN, Lun LI

期刊论文

Optimization model for rotor blades of horizontal axis wind turbines

LIU Xiong, CHEN Yan, YE Zhiquan

期刊论文

中医五脏相关学说研究——从五行到五脏相关

邓铁涛,郑洪

期刊论文

多孔质气体静压轴承在三轴转台设计中的应用

杜金名

期刊论文

Performance of vertical axis water turbine with eye-shaped baffle for pico hydropower

Zhuohuan HU, Dongcheng WANG, Wei LU, Jian CHEN, Yuwen ZHANG

期刊论文

Role of the forkhead transcription factor FOXO-FOXM1 axis in cancer and drug resistance

null

期刊论文

Estimation of power in low velocity vertical axis wind turbine

Sampath S. S.,Sawan SHETTY,Chithirai Pon Selvan M.

期刊论文

FMO3--TMAO axis modulates the clinical outcome in chronic heart-failure patients with reduced ejection

期刊论文

Chidamide inhibits the NOTCH1-MYC signaling axis in T-cell acute lymphoblastic leukemia

期刊论文

Effects of parenteral nutrition with and without GH on the GH/IGF-1 axis after hepatectomy in hepatocellular

CAO Jie, LUO Shimin, LIANG Lijian, LAI Jiaming, CHEN Shanming

期刊论文

IN VITRO ACTIVITY OF EXTRACTS OF FIVE MEDICINAL PLANT SPECIES ON PLANT PATHOGENIC FUNGI

期刊论文

Quality and efficiency improvement technology for five megawatt offshore wind turbines and its application

Huali HAN

期刊论文

硅微z轴谐振陀螺仪负电刚度效应分析及实验验证

夏敦柱,周百令,王寿荣

期刊论文