Application of Vis–NIR hyperspectral imaging in classification between fresh and frozen-thawed pork Longissimus Dorsi muscles

Fresh and frozen-thawed (F-T) pork meats were classified by Vis–NIR hyperspectral imaging. Eight optimal wavelengths (624, 673, 460, 588, 583, 448, 552 and 609 nm) were selected by successive projections algorithm (SPA). The first three principal components (PCs) obtained by principal component analysis (PCA) accounted for over 99.98% of variance. Gray-level-gradient co-occurrence matrix (GLGCM) was applied to extract 45 textural features from the PC images. The correct classification rate (CCR) was employed to evaluate the performance of the partial least squares-discriminate analysis (PLS-DA) models, by using (A) the reflected spectra at full wavelengths and (B) those at the optimal wavelengths, (C) the extracted textures based on the PC images, and (D) the fused variables combining spectra at the optimal wavelengths and textures. The results showed that the best CCR of 97.73% was achieved by applying (D), confirming the high potential of textures for fresh and F-T meat discrimination.     

基于差异半监督学习的相关理论分析

基于差异的半监督学习属于半监督学习和集成学习的结合,是近年来机器学习领域的研究热点.但相关的理论研究较缺乏,且都未考虑存在分布噪声的情况.文中首先针对基于差异的半监督学习的特点,定义一种分类噪声和分布噪声的混合噪声(HCAD).其次给出算法在HCAD噪声下的可能近似正确(PAC)理论分析及其应用实例.最后基于投票边缘函数,推导出在HCAD噪声下多分类器系统的泛化误差上界,并给出相关证明.文中开展的理论研究可用于设计基于差异的半监督学习算法及评估算法的泛化能力,具有广阔的应用前景.     

氧透高压回流阀操作不当造成停车故障的分析

本文比较详细地阐述了杭氧 3TYS89+2TYS6 0氧透的轴封和轴封差压控制情况 ,分析了操作高压回流阀不当造成氧透轴封差压联锁停车的原因 ,并针对当时情况提出了处理方法     

油气田产量预测的校正方法

人们已经提出了许多预测油气田产量的数学模型, 但这些预测模型应用于某些油气田的产量预测时, 不能取得令人满意的效果。为此, 笔者提出了油气田产量预测的校正方法, 这一研究弥补了以往产量预测模型的不足。实践结果表明, 经校正后的预测模型,与其它预测模型相比,具有更高的预测精度。     

正确软件开发的集成式设计支持环境

本文介绍了国外特别是德国在正确软件开发支持系统方面的进展，重点阐述集成了各种方法学语言及正确性证明逻辑的集成式正确软件开发支持系统（ＫＯＲＳＯ），它的系统特点、形式机制及系统组织体系。     

Excel答案非唯一考核点自动阅卷技术分析

Excel操作题自动阅卷,一般通过VBA技术实现自动阅卷,然而现有Excel阅卷方法在处理答案非唯一考核点时容易出现阅卷错误.针对Excel操作最可能出现答案非唯一的两种考核点,即条件区域的定义和函数的使用,通过举例,介绍有助于准确阅卷的几种方法,包括排序法、等效引用法、列举法、特殊参数验证法、等效条件法.实践证明,使用这些方法能够减少答案非唯一考核点自动阅卷过程中出现误判、漏判,提高了自动阋卷的准确性.     

Child Restraint Fitting Stations reduce incorrect restraint use among child occupants

This study evaluated the effectiveness of the NSW Restraint Fitting Station Network in preventing incorrect use of rearward facing and forward facing child restraints.The way children used restraints was observed randomly as they arrived at observation sites during a cross-sectional ecological study across New South Wales, Australia. Trained researchers examined restraint system installation once the child left the vehicle. A structured interview was also conducted with the driver. Logistic regression was used to examine the association between parental report of ever having the restraint checked at a Restraint Fitting Station and whether or not the restraint was used correctly, while controlling for potential confounders and accounting for the complex sample design. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.The results demonstrated that children of respondents who did not use Restraint Fitting Stations were 1.8 times more likely to be incorrectly using their restraints (95% CI 1.1–2.8) than children of Restraint Fitting Station users. Regardless of whether or not a Restraint Fitting Station had been used, there was a trend towards a greater likelihood of incorrect restraint use as the length of restraint ownership increased (OR 1.3 95% CI 1.0–1.7).These results are important for developing strategies aimed at reducing child occupant casualties by reducing the rate of incorrect restraint use, and support programs encouraging the use of Restraint Fitting Stations and similar services as a countermeasure to incorrect use.     

汉明码检验系统的电路实现

本文首先介绍了汉明码的特点和编码规则,并以此为基础着重讨论了一个(15,11)的汉明码检测系统的数字电路实现过程。     

斜角裁切机切边送料系统的开发与研制

介绍了在斜角裁切机切边送料系统开发与研制过程中,如何实现定长送料和纠偏的工艺过程。通过采用电机带动同步带结构和上下橡胶辊以及上下同步移动气缸相结合的传动结构设计了定长送料机构,保证了偏光片定长送料的精度。通过采用纠偏电机和纠偏控制器以及超声波传感器等设计了送料纠偏机构,保证了送料的精度,同时提高了送料的效率。