Introduction of a nonlinearity measure for principal component models

Although principal component analysis (PCA) is an important tool in standard multivariate data analysis, little interest has been devoted to assessing whether the underlying relationship within a given variable set can be described by a linear PCA model or whether nonlinear PCA must be utilized. This paper addresses this deficiency by introducing a nonlinearity measure for principal component models. The measure is based on the following two principles: (i) the range of recorded process operation is divided into smaller regions; and (ii) accuracy bounds are determined for the sum of the discarded eigenvalues. If this sum is within the accuracy bounds for each region, the process is assumed to be linear and vice versa. This procedure is automated through the use of cross-validation. Finally, the paper shows the utility of the new nonlinearity measure using two simulation studies and with data from an industrial melter process.     

西北地区节水灌溉市场与技术需求

西部开发需要大量的生态用水，从节水灌溉设备市场分析，节水灌溉专用泵阀、新型输水管材、高效低能喷微灌设备及材料的需求量很大，技术需求与亟待研究开发的关键技术和设备也很多。从西北地区水资源状况与需求看，节水灌溉市场有很大潜力。     

初春施工技术要点探讨

论述了初春施工这个特定的施工季节所具有的特征，从气候、施工人员、工程情况及受冻土体等方面对初春施工易出现的问题进行了分析，对施工过程及施工技术规律性问题做了细化性研究和探讨。     

形状记忆聚氨酯的结构与性能研究

以 2 ,4 -甲苯二异氰酸酯 (2 ,4 -TDI)、不同分子量的聚己二酸丁二醇酯 (PBAG)和 1,4-丁二醇 (BDO)为原料合成了具有形状记忆功能的聚氨酯材料。通过DSC、弯曲实验和力学实验 ,研究了形状记忆聚氨酯的性能 ,发现软段高度结晶和硬段聚集形成硬段微区是其具有较好形状记忆性能的必要条件。     

地理环境与先秦南北饮食文化

先秦时期是我国饮食文化的形成时期，受地理环境的强烈影响，逐渐形成了以秦岭-淮河一线为界的南北两个主要的饮食文化区域：黄河中下游地区为中心的北方饮食文化区，是以旱地粮食作物黍、稷、粟等为主食，陆地动物为辅食，烧、烤、炸为主要烹饪方法的北方饮食风味；长江中下游地区为中心的南方饮食文化区，是以水田粮食作物稻米为主食，陆地动物和水产动植物为辅食，蒸、炖、煎为主要烹饪方法的南方饮食风味。     

GIS中实时建立区域拓扑关系的快速算法

针对GIS中建立区域拓扑关系的实时性要求,论文提出一个结合基于图的拓扑信息和基于几何的左转算法的区域拓扑关系生成算法。利用区域的连通性提高了算法效率,左转算法保证了算法的可靠性。     

Functional and sensory properties of chicken meat from spent-hen carcasses deboned manually or mechanically in Jordan

Samples of chicken meat from spent laying hens were obtained by four different methods: (1) manual deboning of whole carcasses; (2) manual deboning of skinned carcasses; (3) mechanical deboning of whole carcasses; and (4) mechanical deboning of skinned carcasses. The meat was packaged, frozen and stored at ?18 °C for up to 3 months. Functional properties studied were pH, emulsifying capacity (EC) and water‐holding capacity (WHC) and, in addition, pigment concentration was investigated. Sensory properties included aroma, colour, texture and overall acceptability, as judged by a trained panel using a nine‐point hedonic scale. Removal of the skin prior to deboning by either method gave significantly higher values (P < 0.05) for EC, while WHC values were not significantly different among the experimental treatments, despite higher pH values for mechanically‐deboned meat, with and without skin. Pigment concentrations were highest in meat from Treatment 4 and lowest for Treatment 1, but values for both methods of deboning were affected by the presence of skin. There were no significant differences between treatments for any of the sensory properties studied. Changes occurring in the meat during frozen storage are described.     

一种基于偏最小二乘法的室外光照估计算法

针对固定视点下的室外场景在线视频光照求解问题,提出一种基于偏最小二乘室外场景实时光照估计算法.在离线阶段提取场景中对光照变化较为敏感的区域,并将这些区域像素值的均值与方差的无偏估计作为场景图像的统计参数,再利用偏最小二乘回归分析建立场景的光照参数与图像统计参数之间的模型;在在线阶段使用所建立的模型实时估计视频每一帧的光照条件.实验结果表明,使用该算法所求解的光照参数对虚拟物体进行绘制并将其融入视频中后,合成场景真实感很强.     

Human DDX3X Unwinds Japanese Encephalitis and Zika Viral 5′ Terminal Regions

Flavivirus genus includes many deadly viruses such as the Japanese encephalitis virus (JEV) and Zika virus (ZIKV). The 5′ terminal regions (TR) of flaviviruses interact with human proteins and such interactions are critical for viral replication. One of the human proteins identified to interact with the 5′ TR of JEV is the DEAD-box helicase, DDX3X. In this study, we in vitro transcribed the 5′ TR of JEV and demonstrated its direct interaction with recombinant DDX3X (K_d of 1.66 ± 0.21 µM) using microscale thermophoresis (MST). Due to the proposed structural similarities of 5′ and 3′ TRs of flaviviruses, we investigated if the ZIKV 5′ TR could also interact with human DDX3X. Our MST studies suggested that DDX3X recognizes ZIKV 5′ TR with a K_d of 7.05 ± 0.75 µM. Next, we performed helicase assays that suggested that the binding of DDX3X leads to the unwinding of JEV and ZIKV 5′ TRs. Overall, our data indicate, for the first time, that DDX3X can directly bind and unwind in vitro transcribed flaviviral TRs. In summary, our work indicates that DDX3X could be further explored as a therapeutic target to inhibit Flaviviral replication     

含水量对渠道保温板保温耐久性的影响及保温板厚度设计

北方渠道大多使用保温板防止混凝土衬砌受冻胀破坏。在计算保温板厚度时为了降低成本,容易忽略保温板使用过程中受各种因素的影响导致保温效果变差的情况,使混凝土衬砌达不到设计使用年限便提前被破坏。内蒙古河套灌区试验结果表明,由于受酸雨、冻融作用、含水量等因素的影响,保温板保温效果平均每年降低0.9℃,其中受含水量变化的影响最大。经试验测得:聚苯乙烯保温板(EPS)含水量每增加1%,会导致导热系数增大5%。基于多层材料串联热阻叠加原理和热阻等效原理,对保温板厚度计算公式进行完善,并提出相应的铺设方法和施工技术要求。该设计对保温板在季节性冻土区的推广应用具有一定参考价值。