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This paper presents a novel approach for improving the estimation accuracy of the road profile for a vehicle suspension system. To meet the requirements of road profile estimation for road management and reproduction of system excitation, previous studies can be divided into data-driven and model based approaches. These studies mainly focused on road profile estimation while seldom considering the uncertainty of parameters. However, uncertainty is unavoidable for various aspects of suspension system, e.g., varying sprung mass, damper and tire nonlinear performance. In this study, to improve the estimation accuracy for a varying sprung mass, a novel algorithm was derived based on the Minimum Model Error (MME) criterion and a Kalman Filter (KF). Since the MME criterion method utilizes the minimum value principle to solve the model error based on a model error function, the MME criterion can effectively deal with the estimation error. Then, the proposed algorithm was applied to a 2 degree-of-freedom (DOF) suspension system model under ISO Level-B, ISO Level-C and ISO Level-D road excitations. Simulation results and experimental data obtained using a quarter-vehicle test rig revealed that the proposed approach achieves higher road estimation accuracy compared to traditional KF methods. [ABSTRACT FROM AUTHOR]

Modal parameter model acts as an analytical model of tire, because it can represent the entire tire characteristics, when applied to the tire modelling. However, without considering the effect of transfer characteristics of adjacent tread spring elements, the accuracy of modal parameter model may be limited in previous studies. Based on contact mechanics and the modal parameter model, a novel tread model is proposed considering tread transfer characteristics, and then a modified model using the modal parameters was obtained using the novel tread model. The effects of tire external characteristics were analyzed by modifying the modal parameter static vertical model. Finally, the experimental and calculated data were compared, the proposed tread model improved the accuracy of calculation. The results show that the tread transfer characteristics significantly affect contact length, i.e., by improving the predictive accuracy by 50 %, and the effect on improving the squat of tire can be ignored. The developed model may help to optimize tire modelling. [ABSTRACT FROM AUTHOR]

The synthesis and determination of the crystal structures of eight mixed-ligand divalent coordination polymers based on 3,5-diiodobenzoic acid (HL) and ancillary nitrogen ligands (bpy = 4,4'-bipyridine,bpe = 1,2-bis(4-pyridyl)ethene, p-bix = 1,4-bis(imidazol-1-ylmethyl)-benzene, bpp = 1,3-bi(4-pyridyl)propane, bbi = 1,1'-(1,4-butanediyl)bis(imidazole), namely, [Zn(L)2(p-bix)]n(1), [Zn3(L)6(bpp)]n(2), [Cd1.5(L)3(bpp)]n(3), [Ni(L)2(bpe)∙H2O]n(4), [Co(L)2(p-bix)]n(5), [Co1.5(L)3(bpy)0.5]n(6), [Mn3(L)6(bpe)]n(7), and [Mn3(L)6(bbi)]n(8), have been reported. They were well characterized by elemental analysis, IR spectra, and single crystal X-ray diffraction. Compounds 1-5 all exhibit three-dimensional (3D) supramolecular structures based on interchain type II I...I halogen bond interactions,or hydrogen bonding and type I I...I contacts, respectively. Moreover, π...π interactions are found in the structure of 3. In compounds 6-8, similar two-dimensional (2D) metal-organic layers are expanded to 3D supramolecular structures based on type II I...I halogen bond interactions or type I I...I contacts, respectively. Our structural analyses promise to help demonstrate that organic iodine prefers type II I...I halogen bond interactions. In addition, it is of importance to evaluate the contributing role of I...I halogen bonds or I...I contacts in crystal structure packing. In addition, their thermal analysis, X-ray powder diffraction, and UV-vis absorption spectra have been investigated as well. [ABSTRACT FROM AUTHOR]

We propose a diamond-based micron-scale sensor and perform high-resolution B-field imaging of the near-field distribution of coplanar waveguides. The sensor consists of diamond crystals attached to the tip of a tapered fiber with a physical size on the order of submicron. The amplitude of the B-field component B is obtained by measuring the Rabi oscillation frequency. The result of Rabi sequence is fitted with a decayed sinusoidal. We apply the modulation-locking technique that demonstrates the vector-resolved field mapping of the micromachine coplanar waveguide structure (CPW). B-field line scan was performed on the CPW with a scan step size of 1.25 μm. To demonstrate vector resolved rf field sensing, a full field line scan acts (was performed) along four NV axes at a height of 50 μm above the device surface. The simulations are compared with the experimental results by vector-resolved measurement. This technique allows the measurement of weak microwave signals with a minimum resolvable modulation depth of 20 ppm. The sensor will have great interest in micron-scale resolved microwave B-field measurements, such as electromagnetic compatibility testing of microwave integrated circuits and characterization of integrated microwave components. [ABSTRACT FROM AUTHOR]

A polar homochiral 3D MOF [{Co2(L)(bpe)(H2O)}·5H2O]n constructed with cobalt(II) and a new ligand N-(1,3-dicarboxy-5-benzyl)-carboxymethylglycine (H4L) accommodates ordered helical water streams in its helical grooves. It provides the first example of switchable ferroelectric and optical behavior through two-step reversible single-crystal to single-crystal transformation (SCSC) upon desorption/adsorption of water spirals and coordinated water molecules, respectively. [ABSTRACT FROM AUTHOR]