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Broadband perfect absorbers with an average absorptivity of 96.2% in the 200–1500 nm are proposed. Complete spherical Pt shells with induced cracks are fabricated from monolayer microspheres along with heating using conformal oxide and metal coating.

Broadband optical absorbers are significant for applications in solar energy harvesting, thermal emitters, and infrared detection. Broadband solar absorbers should have the advantages of broad solar spectrum utilization, good thermal stability, easy large-area fabrication, polarization independence, and insensitivity to incident angle. In this work, the ultra-broadband absorption of metallic truncated nanocones in the ultraviolet–visible–near-infrared spectral region is reported. The average absorptivity in the wavelength range of 100–2500 nm is 96.11%, and greater than 96% absorptivity can be continuously maintained in the range of 160–1470 nm. The results of a finite-difference time-domain simulation using air mass 1.5 show that the metallic truncated nanocones have an average solar absorptivity of 94.22% between 280 and 2500 nm. The absorptivity in the wide oblique angle range of 0–70° along all polarizations is higher than 80%. The effect of the geometric parameters of the metallic truncated nanocones on broadband absorption is discussed. The interaction of local surface plasmonic resonance, Fabry-Perot cavity resonance, and magnetic polarization resonance in the truncated nanocones leads to the high absorption performance. The feasibility of fabricating the truncated nanocones was verified using self-assembled monolayer colloidal crystal-assisted ultraviolet light lithography followed by atomic layer deposition of platinum. The average absorptivity of 74.82% presented from photoresist and platinum arrays is close to that of the simulated data.

Maintenance serves as the major engineering service in the PSS delivery model, it has a key role in delivering performance driven solutions. Leveraging the strengths of a dynamic PSS network for maintenance performance has become essential to satisfy rapidly changing customer demands and to remain competitive. Firms are therefore aiming to further their maintenance competence, which we define as the ability of the PSS networks to improve products and services, based on the processes and relationships established with PSS partners and customers. The purpose of this research is therefore to provide insight into how intangible capital among PSS network partners can be effectively utilized for maintenance performance. This study examines how intangible capital and knowledge further the development of maintenance competence within the context of a PSS network. A theoretical model is verifiedthroughstructural equation modeling utilizing survey data collected from a PSS network, which consists ofa large agricultural machine manufacturer, three providers for intelligent terminal instruments and 1000 small- and medium-sized service stations and distributors in the manufacturing industry. The results indicated that human capital and organizational capital are positively related to knowledge type development, which in turn has a positive effect on maintenance performance in PSS networks. This study contributes to the theoretical development of a conceptual model by examining the mediating role of explicit knowledge and tacit knowledge in the relation human capital and organizational capital with maintenance performance. Conclusively, an outlook for further research is given.

To solve the reusing and sharing problems of fault knowledge which is short of fault knowledge base, research of knowledge representation and knowledge discovery method of agricultural machinery with the maintenance support to knowledge discovery and reuse purpose was carried out. With Chinese segmentation tools, information extraction technologies of Chinese fields in agricultural machinery fault data were studied. Research of data mining technology about mining implicit relevance information from fault data for founding of agricultural fault knowledge base by association rules algorithm was studied. This method was proved feasible to build agricultural machinery maintenance fault knowledge base by dealing with the real data.

A Cascode SiGe BiCMOS low-noise amplifier (LNA) is presented for ultra-wideband (UWB) application. The emitter degenerative inductive technique is employed to achieve input impedance matching and optimize the noise performance. The output impedance matching is achieved by resistance-inductor shunt feedback. The current reuse topology is adopted to achieve high gain with low power consumption. Based on TSMC 0.35μm SiGe BiCMOS process, the topology and chip layout of the proposed LNA have been designed, its area is 0.62×0.64 mm2. The simulation results of the LNA demonstrate that in the range of UWB, the noise figure is 2.6∼4.1 dB, the gain is 19.3∼20.8 dB, gain flatness is ±0.75 dB, linearity is −4∼ −7dBm, the input and output match well, the LNA is unconditionally stable in the whole band.

A SiGe HBT low-noise amplifier (LNA) for UWB application is presented. According to the analysis for noise of common base transistor, noise canceling structure for SiGe HBT is proposed to reduce the noise arising from common transistor, thus reduce the noise of LNA. Meanwhile it also compensate the gain of the LNA, thus improves the gain flatness. The chip layout has been designed, its area is 0.56×0.53 mm2. The simulation results of the LNA demonstrate that in the range of UWB, the noise figure is reduced 2 dB compared with the case without noise canceling, the gain is 16.4∼17.4, gain flatness is ±0.5dB, linearity is •6dBm.