基于AST分析的时间定额数据库的建立与应用

为了提高工时定额数据的准确性,阐述了通过运用预定动作时间法中的AST分析技术,以柳工工艺定额管理系统为载体,建立时间定额数据库的方法,以及在目前柳工的应用实践情况,该方法为企业的精益生产、标准化作业、现场改进、人机分析、瓶颈管理、车间布置等方面提供了强有力的数据支持,对提升企业管理水平和提高生产效率,起到了积极的作用。     

一个重建GCC抽象语法树的方法

抽象语法树(AST)作为程序的一种中间表示形式,在程序分析等诸多领域有广泛的应用。传统的建立AST的方法是通过词法和语法分析的方法。该文提出了一种利用GCC前端结果建立AST的方法,这种方法将GCC编译源程序产生的AST文件,经过一定的格式转换变为XML文档,然后使用XML文档解析器读取该文档,重新建立AST。     

从GCC的AST文本提取C源程序静态信息的方法

为了能够正确的分析源程序的控制依赖关系和数据依赖关系,以便在此基础上进行程序切片及冗余代码和重复代码检测,提出一种利用GCC抽象语法树(AST)文本来提取源程序静态信息的方法.首先,对GCCAST文本进行标准化及消除文本中与控制流分析和数据流分析无关的结点信息;其次,构建控制依赖子图;同时如果需要数据流分析,在控制依赖子图的基础上构建控制流图,在控制流图的基础上构建数据流子图;最后通过引入过程间分析来完善系统依赖图.实验结果表明,这种方法基本能正确的分析源程序的控制依赖和数据依赖关系,具有更好的适应性和灵活性.     

小波自适应软门限信号去噪方法研究

简要介绍了小波多分辨分析的理论基础,在分析信号及噪声随小波分析尺度变化而变化的规律之后,针对小波去噪的核心问题——阈值的设定提出了一种新的方法．即自适应软门限去噪的方法。这种方法具有明确而直观的物理意义,实现简单、方便,通过实验证明,自适应软门限去噪方法具有较好的去噪效果。     

Antioxidant activity of white rice,brown rice and germinated brown rice (in vivo and in vitro) and the effects on lipid peroxidation and liver enzymes in hyperlipidaemic rabbits

Antioxidant activity of different rice extract and the effect on the levels of antioxidant enzyme activity, superoxide dismutase (SOD) and glutathione peroxidase (GPx), vitamin E, lipid peroxidation and liver enzymes in hyperlipidaemia rabbits were investigated. Germinated brown rice (GBR) has the highest antioxidant activity compared to white rice (WR) and brown rice (BR). All rice grains increased the activity of SOD and GPx. However, vitamin E levels increased only in the groups that received the BR and GBR diets. The reduction of lipid peroxidation levels and activity of hepatic enzymes (alanine transferase, ALT and aspartate transaminase, AST) were only significantly observed in the GBR group. In conclusion, GBR supplementation has the greatest impact on increasing antioxidant enzyme activity and vitamin E level and on reducing lipid peroxidation in hypercholesterolaemia rabbit, thereby preventing the formation of atherosclerotic plaques. Furthermore, GBR diet can also reduce the level of hepatic enzymes.     

Piperine reverses high fat diet-induced hepatic steatosis and insulin resistance in mice

This study examined the effect of piperine on hepatic steatosis and insulin resistance induced in mice by feeding a high-fat diet (HFD) for 13 weeks and elucidated potential underlying molecular mechanisms. Administration of piperine (50 mg/kg body weight) to mice with HFD-induced hepatic steatosis resulted in a significant increase in plasma adiponectin levels. Also, elevated plasma concentrations of insulin and glucose and hepatic lipid levels induced by feeding a HFD were reversed in mice when they were administered piperine. However, piperine did not reduce body weight and other biochemical markers to an extent where they became equal to the levels found in the CD-fed mice. Piperine reversed HFD-induced down-regulation of adiponecitn-AMP-activated protein kinase (AMPK) signalling molecules which play an important role in mediating lipogenesis, fatty acid oxidation and insulin signalling in the livers of mice. The expressions of lipogenic target genes were decreased, whereas the expression of carnitine palmitoyltransferase 1 (CPT1) gene involved in fatty acid oxidation was increased in the livers of the Pin50 group. Piperine significantly decreased the phosphorylation of insulin receptor substrate-1 (IRS-1) compared with the HFD-fed mice. Administration of piperine appeared to reverse preexisting HFD-induced hepatic steatosis and insulin resistance, probably by activation of adiponectin-AMPK signalling in mice.     

Thermal effectiveness characteristics of low approach indirect evaporative cooling systems in buildings

Meteorological enthalpy analysis of temperate and maritime climates above latitude 45°N suggests that the water-side evaporative cooling technique has considerable unrealised potential with contemporary “high temperature” building cooling systems—such as chilled ceilings and displacement ventilation. As low approach conditions are the key to exploiting the cooling potential of the ambient air, thermal performance at such conditions needs to be investigated. To address the research issues, an industrial scale test rig, based on a low approach open cooling tower and plate heat exchanger and designed to maximise evaporative cooling potential, has been constructed.     

一种建立控制依赖子图的方法

提出一种基于GCC(GNU Compiler Collection)抽象语法树文本建立控制依赖子图的方法,消除抽象语法树文本中与分析控制流无关的信息,将消除冗余后的抽象语法树文本转化为以邻接表为存储结构的抽象语法树的算法,从而高效地完成了抽象语法树的解析。基于以邻接表为存储结构的抽象语法树建立了控制依赖子图。通过实验证明了该方法的正确性和适用性。     

Study on the separation of 100 TeV γ-rays from cosmic rays for the Tibet ASγ experiment

A γhadron separation analysis is described for the observed air shower events with primary energy above 100 TeV based on the Tibet ASγ detector configuration. The shower age and size parameters are fitted from the measured lateral density distribution and     

汽轮机电气-液压油系统故障处理

茂名石化动力厂热电三车间1号汽轮机电气-液压(electro-hydraulic,EH)油系统在调试过程中出现了3次故障:第一次是在进行静态超速保护控制(overspeed protection control,OPC)试验时,EH油系统压力和自动停机遮断(auto shut-down or trip,AST)油压力降至3MPa以下(汽轮机跳闸整定值为9.5MPa);第二次是危急保安器复位后,AST油和OPC油母管压力小于3MPa;第三次是中压抽汽调节阀打不开。采用排除法查找出故障原因:第一次故障的原因是线性可变差动变压器(linear variable differential transformer,LVDT)的反馈量与数字式电液调节系统(digital electro-hydraulic control system,DEH)的指令出现偏差;第二次故障是高压调节阀的LVDT松动所致;第三次故障是节流孔堵塞所致。提出解决办法:优化控制系统,使OPC系统动作时调节阀指令复零;固定好LVDT;清理节流孔。