交错群图的混合故障诊断问题研究

为了衡量以交错群图为拓扑结构的多处理器系统在混合故障环境下的故障诊断能力,研究了交错群图在HPMC模型下的h-限制点诊断度和r-限制边诊断度。根据这2种混合故障诊断度的性质,得到了它们之间的关系。考虑到交错群图中相邻的顶点有公共邻点,将h和r划范围讨论。借助反证法,得到了交错群图在1≤h≤2n-7时的h-限制点诊断度是2n-h-4。然后由h-限制点诊断度和r-限制边诊断度的关系,确定了交错群图在3≤r≤2n-5时的r-限制边诊断度是2n-r-4。此外,通过构造相异的一致故障对并证明是不可区分的,确定了交错群图在h=2n-6,2n-5,2n-4时的h-限制点诊断度分别是1、0、0;在r=1,2时的r-限制边诊断度分别是2n-6、2n-7。这些结果显示出交错群图在混合故障环境下可自我识别故障元素的最大数值,体现了系统最大的故障诊断能力。

纤维素醚对砂浆塑性自由收缩的影响

采用非接触式激光位移传感器连续测试加速条件下甲基羟丙基纤维素醚(HPMC)改性水泥砂浆的塑性自由收缩,并同时观测其失水率,分别建立了HPMC掺量与塑性自由收缩、失水率回归模型.结果表明:水泥砂浆塑性自由收缩随HPMC掺量的增加呈线性递减,掺0.1%～0.4%(质量分数)的HPMC可以减少水泥砂浆30%～50%的塑性自由收缩;随着HPMC掺量的增加,水泥砂浆的失水率亦呈线性递减,掺0.1%～0.4%的HPMC可以降低水泥砂浆9%～29%的失水率;HPMC掺量与自由收缩、砂浆失水率均呈明显的线性关系.HPMC减少水泥砂浆塑性自由收缩的原因源于其优异的保水作用.

In vitro-in vivo correlation study on nimesulide loaded hydroxypropylmethylcellulose microparticles

This study involves mathematical simulation model such as in vitro-in vivo correlation(IVIVC) development for various extended release formulations of nimesulide loaded hydroxypropylmethylcellulose(HPMC) microparticles(M1,M2 and M3 containing 1,2,and 3 g HPMC,respectively and 1 g drug in each) having variable release characteristics.In vitro dissolution data of these formulations were correlated to their relevant in vivo absorption profiles followed by predictability worth analysis of these Level A IVIVC.Nimaran was used as control formulation to validate developed formulations and their respective models.The regression coefficients of IVIVC plots for M1,M2,M3 and Nimaran were 0.834 9,0.831 2,0.927 2 and 0.898 1,respectively.The internal prediction error for all formulations was within limits,i.e.,<10%.A good IVIVC was found for controlled release nimesulide loaded HPMC floating M3 microparticles.In other words,this mathematical simulation model is best fit for biowaiver studies which involves study parameters as those adopted for M3 because the value of its IVIVC regression coefficient is the closest to 1 as compared to M1 and M2.