Search

The glabrous and hairy skin of the human body contains different types of mechanoreceptive afferents. At present, consumers and researchers usually use hands (the glabrous palm) to evaluate and study the contact perception of fabric, which mainly contains two aspects of fabric performance, handle and comfort. However, in use, fabric in most cases contacts the hairy skin of the human body, rather than the glabrous skin. In order to investigate the cognitive differences in the brain for fabric touch on the two types of skin, we used the same silk fabric to touch the palm and forearm of nine subjects, and observed the brain responses simultaneously using functional magnetic resonance imaging. The results showed that for palm stimulation, activations were mainly evoked in somatosensory cortices, and deactivation in the insula cortex and, in contrast, for forearm stimulation, more activations were evoked in the insula cortex, and deactivation mainly in the primary somatosensory cortex. It is suggested that there are more sensory information arising from fabric touch on the glabrous skin, and more emotional information on the hairy skin. Therefore, for discriminating the physical properties (e.g. fabric hand) of fabric, it is better to receive fabric touch using glabrous skin, and for evaluating the emotional perception (e.g. fabric comfort) of fabric touch, it is better using hairy skin.

Background/purpose Using touching movement of fingers, human subjects can discriminate various tactile perception of fabric. As a continuation of the previous study, we aim to further investigate the discriminative mechanisms of the brain cognition to tactile stimulation of different fabric. Methods We used functional magnetic resonance imaging to observe the brain responses when the subjects touched linen fabric, as well as revisited the data from the previous silk fabric. And all the subjects were asked to compare the perception of touching the two fabric. Results Combining the results of brain responses and perception comparison, we found that activation in the primary somatosensory cortex (SI) and the secondary somatosensory cortex (SII), especially parietal operculum 1 (OP1) in this region, could discriminate this two kinds of fabric distinctly. Conclusion It is suggested that the functional regions involved in the macrogeometric properties of fabric (such as pliability) is in SI, and the perception of microgeometry of fabric surface (such as roughness and glutinousness) in SII, especially in the sub-region OP1 of the OP. Besides, activation in motor cortex can be a reference for the characterization of the brain cognition on the tactile stimulation of fabric.

The Huoqiu iron ore field in northwest Anhui Province is located in the North China Craton (NCC). As a large banded iron formation (BIF) iron ore field, ore bodies occur in a middle-high grade of Neoarchean metamorphic formation, forming a banded silicon–iron series from north to south. The main ore bodies can be divided into two sub-belts from bottom to upper layers, i.e. the A + B ore belt consisting of leptynite–schist–magnetite–quartz formation, and the D ore belt consisting of schist–marble–hematite–quartz formation. Based on a dataset from geological settings, geophysical and geochemical exploration, ore-forming conditions and structural analysis of the iron deposit, we discuss structural types, sedimentary environments, deep tectonic and ore-controlling factors as well as characteristics and distribution of this colossal BIF ore field in the Huoqiu region. Using LA-ICP-MS techniques, we obtained the oldest U–Pb age of ca. 2.7 Ga for plagioclase amphibolite as its original rock, and 1.8 Ga for magmatic granite in the Huoqiu Group. The Hf isotopes of zircon were also determined, resulting in the oldest Hf model age of 3.5 Ga. Geochemical data indicate that the protolithes of amphibolites belong to a series of subalkaline rocks with enrichments of large ion lithophile elements and depletions of high field strength elements, which are typical volcanic arc rocks. The amphibolites have low K 2 O concentrations with low ratios of Ti/V (22.7 to 25.9 averaging 24.5), similar to island arc tholeiite. This suggests that the iron deposit and BIF are of the Superior type in the Huoqiu region.

Aiming at the comprehensive performance evaluation of urban public transport network, this paper established an evaluation index system of urban public transport network with target layer, criterion layer and index layer based on analyzing its subjective and objective influencing factors. Otherwise, a method for determining the weight of the comprehensive performance evaluation index of the city bus network and its evaluation model were presented by using fuzzy mathematics principle. The validity and feasibility of the model and method are further validated by the evaluation of the comprehensive performance of the existing bus network in Lanzhou New District. The evaluation results provide theoretical support for the further optimization of urban bus network.

The compressive strength of the contrast mortars and test mortars at different curing temperatures at different ages were tested. Effect of curing temperature on the strength of the test mortars and the contrast mortars was analyzed. The relative activity index and absolute activity index of the silica fume were studied. The mercury porosimetry method was used to test the pore structure of mortar specimens, and the improving effect of silica fume on the pore structure of mortar specimens under different curing temperatures was analyzed. The results show that with the increase of age, the decrease of curing temperature will cause the strength of mortar specimens to slow down. At the 3d and 7d ages, with the decrease of curing temperature, the absolute activity value of silica fume gradually increases. After 7 days of age, with the decrease of curing temperature, the absolute activity of silica fume gradually decreases. With the increase of curing age, the relative activity of silica fume decreases at first and then increases at 20°C and 10°C. The relative activity value of silica fume under the maintenance of 5°C and -3°C increased first and then decreased gradually. The addition of silica fume in the concrete improved the internal pore structure of the specimen, and the effect of curing temperature on the specimen was consistent.

Background/purpose Human subjects can tactually estimate the perception of touching fabric. Although many psychophysical and neurophysiological experiments have elucidated the peripheral neural mechanisms that underlie fabric hand estimation, the associated cortical mechanisms are not well understood. Methods To identify the brain regions responsible for the tactile stimulation of fabric against human skin, we used the technology of functional magnetic resonance imaging (fMRI), to observe brain activation when the subjects touched silk fabric actively using fingers. Results Consistent with previous research about brain cognition on sensory stimulation, large activation in the primary somatosensory cortex (SI), the secondary somatosensory cortex (SII) and moto cortex, and little activation in the posterior insula cortex and Broca's Area were observed when the subjects touched silk fabric. Conclusion The technology of fMRI is a promising tool to observe and characterize the brain cognition on the tactile stimulation of fabric quantitatively. The intensity and extent of activation in the brain regions, especially the primary somatosensory cortex (SI) and the secondary somatosensory cortex (SII), can represent the perception of stimulation of fabric quantitatively.

Flow distribution is one of the classic areas of transportation. With the vigorous development of the transportation corridor, the traditional flow distribution algorithm based on the shortest path no longer meets the current transport situation. This paper is based on the model of freight flow distribution by various transportation modes of the regional transportation corridor, combined with characteristics and advantages of each transport mode, so as to reduce the complexity of the model solution. Then this paper will present an actual optimal solution which predicts the burden with different modes of transport freight within transport channels. Data will be offered for regional transport channel construction.