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Here, using a facile hydrothermal method, the single-crystalline ZnO nanoflowers were firstly synthesized and then annealed at different temperatures from 500 to 900 °C. The results revealed that the as-synthesized samples were flower-like ZnO structures composed of many hollow nanorods; after annealing at 500 °C, hollow nanorods were changed into solid parts. Also, using the as-synthesized and annealed ZnO nanoflowers as photosensitive layers, respectively, a series of ultraviolet photodetectors were built. The results demonstrated that the ultraviolet photodetector based on the ZnO nanoflowers annealed at 800 °C had the best performance when they were exposed to 365 nm light with light intensity of 71 μW/cm2 and its sensitivity, responsivity, gain, response, and decay time were 19,991.3 at − 0.1 V, 9.7 A/W at 5 V, 33.2 at 5 V, 17.1 s, and 49.5 s, respectively. Therefore, a new avenue can be opened to construct low cost and high-sensitivity ultraviolet photodetectors by the annealed ZnO nanoflowers.

Alternating current (ac) impedance spectra facilitate lithium-ion battery management. Realizing a low-cost and low-complexity onboard impedance measuring system is a vital issue for the management based on the ac impedance. In the article, a novel impedance measuring system combined with a high-power dual active bridge (DAB) converter and distributed sampling units is proposed and verified. The DAB converter is designed to generate the ac disturbance to ensure a quasi-steady measurement of the battery impedance. The distributed signal sampling units simultaneously measure the voltage and current of all the series-connected battery cells in a module to measure their impedance. The measured impedance in a frequency range of 0.1–500 Hz shows the feasibility of the system. The root-mean-square errors of the measured impedance phase from 0.2 to 200 Hz and the magnitude from 0.1 to 500 Hz are less than 6.9% and 4.0%, respectively. The errors in some frequency ranges are slightly larger, which are analyzed. The novelty is reflected in that the system is easily integrated into a bidirectional onboard charger and compatible with the battery management system, thus reducing costs and complexity. It provides a basis for the onboard application of the battery impedance.

The high-performance, low-cost and simple ultraviolet photodetectors are very promising in some applications. Here, single-crystalline zinc oxide (ZnO) nanoflowers were prepared by combining a facile hydrothermal method with post-annealing treatment, we built an ultraviolet photodetector with an active area of 0.36 cm2 using the as-prepared ZnO nanoflowers. The results showed that under 365 nm light illumination with a light intensity of 77 μW/cm2, the sensitivity, response time, decay time, responsivity and gain of the device were 19991.3 (−0.1 V), 16.4 s, 37.6 s, 9.0 A/W (5 V) and 30.6 (5 V), respectively, indicating that a ZnO nanoflowers UV photodetector with superhigh sensitivity was achieved.

Impedance is closely related to the internal physical and chemical processes of lithium-ion batteries. And the properties of the processes can be characterized and thus more detailed information be provided based on it. In the past decades, the impedance is frequently reported as a powerful tool used in the field of lithium-ion battery state estimation and diagnosis. This paper reviews more than 170 papers and organizes the related research according to three themes of impedance modeling, acquisition, and application under the premise of electric vehicle implementation. The strength and weaknesses of the research in each theme are discussed. Based on the research, the possibility and the value of impedance in onboard battery management are revealed. However, challenges are still faced due to the cost limitations, the complex vehicular conditions, and the time-varying battery states. The unsolved issues are summarized in the conclusion. To realize a more smart battery management system with the impedance, more significant work is still needed.

Based on house of quality concept, the relation between servitization strategy and strategic elements were confirmed through grey relational analysis method. Accordingly, the specific elements characteristics of manufacturing enterprise management core - talents & team and relationship, knowledge resources and flowing, information infrastructure and treatment methods, and organization structure and management were illustrated in three servitization stages - product servitization enlarging, servitization capability continuously improving and servitization integration and innovation. According to elements characteristics, the strategic targets for different servitization stages were brought forward, and four strategic elements specific managing methods were further offered for different servitization stages. The research can offer decision references for manufacturing enterprise to confirm element character and servitization stage, and give effective support to confirm management key points and methods of servitization in manufacturing enterprises at different stages.

The quality and safety of agricultural products has become a vital issue affecting human health and global agricultural trade, and also one of the critical problems to be solved promptly in the world. The establishment of supply chain information of agricultural products from the farm to dining table in all aspects can ensure that quality information of agricultural products in market can be traced, and the quality information of each agricultural product can be inquired, traceable, manageable, and supervised, so as to guarantee quality of agricultural products fundamentally. On the basis of the urgency analysis of the traceability of agricultural products, this paper develops a straight-type traceability system through traceability technology analysis, system function analysis and QR code design. The system has certain promotion effect on the realization of traceability of the agricultural products from "farmland to the dining table", which can provide reference for establishing a perfect management system of quality and safety of agricultural products.

Battery impedance based state estimation methods receive extensive attention due to its close relation to internal dynamic processes and the mechanism of a battery. In order to provide impedance for a battery management system (BMS), a practical on-board impedance measuring method based on distributed signal sampling is proposed and implemented. Battery cell perturbing current and its response voltage for impedance calculation are sampled separately to be compatible with BMS. A digital dual-channel orthogonal lock-in amplifier is used to calculate the impedance. With the signal synchronization, the battery impedance is obtained and compensated. And the relative impedance can also be obtained without knowing the current. For verification, an impedance measuring system made up of electronic units sampling and processing signals and a DC-AC converter generating AC perturbing current is designed. A type of 8 Ah LiFePO4 battery is chosen and the valuable frequency range for state estimations is determined with a series of experiments. The battery cells are connected in series and the impedance is measured with the prototype. It is shown that the measurement error of the impedance modulus at 0.1 Hz–500 Hz at 5 °C–35 °C is less than 4.5% and the impedance phase error is less than 3% at

Lithium ion battery is widely used in electric vehicles. To estimate battery state-of-charge, state-of-health and internal temperature accurately is not only in laboratory but also on-board significant. As a useful tool to study electrochemical system, numbers of estimation methods based on electrochemical impedance spectroscopy arise. The paper focuses on the relation between the battery states and impedance to develop a decoupled state estimation method to satisfy on-board applications. To overcome shortcomings of bulky and high cost of electrochemical impedance spectroscopy equipment in laboratory, an impedance measurement system is designed. Validation results indicate that the battery states can be estimated properly with the impedance based method and the developed measurement system works well, which facilitates the implementation of the impedance based state estimation on board.

Postpartum depression (PPD) is an international public health problem affecting at least 1 in 8 mothers. Known risk factors include: giving birth to a preterm or low birth weight infant, babies with greater symptoms of illness at age 4-6 weeks, formula feeding, younger maternal age, smoking, and fatigue. Prolonged breastfeeding is associated with a reduced risk of PPD but the mechanisms are not well understood. Interventions for PPD focusing on psychosocial risk factors have been largely unsuccessful, suggesting that the condition has a mainly biological basis. The hypothesis proposed for consideration is that breastfeeding protects against PPD by maintaining endogenous retinoids (vitamin A-related compounds) below a threshold concentration. In fact, breast milk is rich in retinoids; pregnant women accumulate retinoids in liver and breast in preparation for lactation; there is increasing evidence that retinoids in higher concentration are associated with cognitive disturbances and mood disorders, including depression and suicide; and prolonged lactation reduces maternal stores of retinoids. Consistent with this hypothesis, it is estimated that an amount of vitamin A is transferred from mother to infant during the first six months of exclusive breastfeeding equivalent to 76% of a dose known to cause acute vitamin A poisoning in an adult. Breastfeeding may thus have evolutionary-adaptive functions for both mother and infant, transferring vital nutrients to an infant unable to feed itself, yet at the same time providing a natural means of reducing potentially toxic concentrations of retinoids in the mother.

According to the design procedure of fault self-diagnosis system and features of automatic transmission system, the list of relation and mapping between fault symptoms and fault causes are made in this paper. Applying the approach of fault self-diagnosis based on fuzzy neural network, fault diagnosis of the automatic transmission electronic control system is realized. The structure of fuzzy neural network and its corresponding learning method and pretreating strategy about the training samples are introduced in this paper. Using MATLAB as simulation platform, this fault diagnosis method is simulated with neural networks toolbox. The simulation results show that this fault diagnosis approach is effective and applied.

To meet with the demands of OAS, the article discusses the application of a new workflow model in constructing and developing a robust and efficient OAS with high integration and overall function, combined with the standards of workflow meta-model, with the center of system modeling and flow control.

This paper has introduced knowledge management and related concept, has analysed the characteristic of native xml database, aims at the bottleneck problem in the development of knowledge management system, Have put forward solution that establishment of knowledge management system based on native xml database,in the finally, have given a reference model of knowledge management system base on Tamino.