Starting from delight-oriented conception,the relationship between delight-oriented design and product form from three levels of delight-oriented design was derived.Meanwhile,it introduced emotional experience which came from the dot line and surface what were the compositions of form circumstantially.The purpose is to introduce delight-oriented form into product design via elaboration of approaches to realizing it,and enhance the affinity between person and product,ultimately,improve the competition of products.
The drop-weight impacts on a thin layer of cyclotetramethylene tetranitramine (HMX) explosive particles have been performed. The drop-weight impact machine is equipped with high-speed photographic techniques. Effects of drop heights and the amount of particles on compaction, deformation, and thermal responses were investigated. Considering the contact plasticity, friction, melting, fracture, as well as chemical reaction, an analytical model based on heating and kinematics equations for a single layer of explosive particles has been developed. The calculated average pressure, loading time and time-to-ignition agree well with experimental measured ones. Threshold conditions for ignition can be derived from the predicted temperature history curves. Individual particles' pressure–strain exhibited stress–strain-like relationships, from which close relations can be found between experimental phenomena and the material's softening/hardening characteristics.
Interface treatments are vital for the bonding performance between ultra-high performance concrete (UHPC) and normal concrete (NC), owing to the mesoscopic nonlinear characteristics caused by interface heterogeneity. This research is devoted to providing an understanding on the mesoscopic behavior of the UHPC-NC interface using the digital image correlation (DIC) technique. Types of interface treatments, including post-installed dowel rebar, high-pressure water, and castellated key, were considered. Results demonstrated that, a three-stage damage evolution consisting of the elastic stage, yield stage, and descend stage was observed in the load-slip curves during the interfacial crack propagation. Aggregate interlock behavior plays a significant role in bonding performance for specimens treated with high-pressure water. Excellent bond strength of 5.42 MPa was obtained by high-pressure water treatment, and the shear strength was enhanced by 146.7% when compared with smooth treatment. With the increase of dowel rebar, the strength improvement of rough treatment was reduced to 73.1%. The failure was mainly observed in the interface transition zone (ITZ) between UHPC and NC. When the ratio of dowel rebar was increased, the failure changed into the ITZ failure between NC mortar and coarse aggregate, fracture of the coarse aggregate was observed near the interface. For specimens treated with a castellated key, the shear strength was 111.3% enhanced by installing dowel rebar. Post-installed dowel rebar restricted the rotation and separation of the castellated key, thus changing the NC failure into UHPC-NC ITZ failure. Meanwhile, the interfacial failure strain is less than 0.5% and 0.25% in the separation and slip direction, respectively, when the brittle failure occurred. While for ductile failure, the failure strain was generally more than 1.0%.
EDITORIAL article Front. Mater., 16 April 2024Sec. Structural Materials Volume 11 - 2024 | https://doi.org/10.3389/fmats.2024.1407364
The evaluation index system of intensive use of arable land was established in view of the actual situation of Wu'an city.The intensive utilization of land condition was analysed using the improved entropy method.The results showed that the intensive use of cultivated land could be divided into three stages from 1997 to 2008.The first from 1997 to 1998 and the third from 2004 to 2008 were increased volatility and the other from 1999 to 2003 was continued to decline.With respect to every village,The overall level of intensive use of the eastern part of cultivated land was not high and most of below 0.5 and the eastern was higher and western was lower from the geographical point of view.
